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Localization properties for nonlinear equations involving monotone operators
Marek Galewski

M. Galewski

March 20, 2020
Using monotonicity methods, the Lagrange multiplier rule and some variational arguments, we consider a type of localization results pertaining to the existence of critical points to action functionals on a closed ball. A variant of the Schechter critical point theorem on a ball in Hilbert and Banach spaces is obtained. Applications to nonlinear Dirichlet problem and to partial difference equations are given in the final part of this paper.
Existence and nonexistence of global solutions for a structurally damped wave system...
Tuan Anh Dao

Tuan Anh Dao

March 20, 2020
Our interest itself of this paper is strongly inspired from an open problem in the paper published by D’Abbicco. In this article, we would like to study the Cauchy problem for a weakly coupled system of semi-linear structurally damped wave equations. The main goal is to find the threshold, which classifies the global (in time) existence of small data solutions or the nonexistence of global solutions under the growth condition of the nonlinearities.
Wavelet Collocation Methods for Solving Neutral Delay Differential Equations
Mo Faheem
Akmal Raza

Mo Faheem

and 2 more

March 20, 2020
A document by Mo Faheem, written on Authorea.
KOROVKIN TYPE APPROXIMATION THEOREM FOR BBH TYPE OPERATORS VIA ABEL SUMMABILITY METHO...
DİLEK SÖYLEMEZ

DİLEK SÖYLEMEZ

March 20, 2020
In this paper, we obtain a Korovkin type approximation theorem via Abel convergence. As an application of this theorem, we construct a non-tensor product BBH type operators in multivariate case. Finally, we proved that our new approximation result works but its classical case does not work.
Mathematical aspects of fluid-multiferroic solid interaction problems
George Chkadua
David Natroshvili

George Chkadua

and 1 more

March 20, 2020
In the paper, we consider a three-dimensional model of fluid-solid interaction when a thermo-electro-magneto-elastic body occupying a bounded region Ω+ is embedded in an inviscid fluid occupying an unbounded domain $\Omega^{-}=^3 \setminus $. In this case, we have a six-dimensional thermo-electro-magneto-elastic field (the displacement vector with three components, electric potential, magnetic potential, and temperature distribution function) in the domain Ω+, while we have a scalar acoustic pressure field in the unbounded domain Ω−. The physical kinematic and dynamic relations are described mathematically by appropriate boundary and transmission conditions. With the help of the potential method and theory of pseudodifferential equations, we prove the uniqueness and existence theorems for the corresponding boundary-transmission problems in appropriate Sobolev-Slobodetskii and Hölder continuous function spaces.
A natural heptameric peptide exhibits multifaceted inhibitory role in the fibrillatio...
Rajanya  Bhattacharyya
Sayan Bhattacharjee

Rajanya Bhattacharyya

and 3 more

March 20, 2020
Background and Purpose Alzheimer’s disease (AD) pathogenesis involves amyloid-β (Aβ) aggregation where the intermediate oligomers are considered the prime toxic species. Here, we aimed to identify an effective peptide sequence from a medicinal plant-derived enzyme having anti-amyloidogenic properties against Aβ. Experimental Approach LC-MS/MS followed by computational analysis identified the active peptide (termed here as Pactive). Visualization techniques along with biophysical and biochemical approaches were used to determine the anti-amyloidogenic potency of the purified enzyme and peptides identified from the enzyme. Cytotoxicity was measured on SHSY-5Y cell lines. Interaction studies were done with bio-layer interferometry (BLI) and bio-stability of the peptide was assessed by NMR. Pactive induced conformational alterations of Aβ monomer and oligomers was determined with DSC and NMR. Key Results A small heptameric peptide (Pactive) identified form a medicinal plant-derived fibrinolytic enzyme proved to be a multifunctional inhibitor against Aβ aggregation. The results suggested that Pactive arrests Aβ molecules in non-toxic off-pathway oligomers that can no longer participate in the cytotoxic fibrillation pathway. Mechanistically, Pactive binding induces conformational alterations in the Aβ molecule, thus modulating its hydrophobicity, one of the key players in inducing aggregation. Conclusions and Implications The study identified a natural peptide Pactive (GFLLHQK) that displays potential anti-amyloidogenic properties against Aβ aggregation. The bio-stability of Pactive in human blood serum as well as its non-toxic nature makes it a promising therapeutic candidate against Alzheimer’s, for which no disease-modifying treatments are available till date.
Dihydroartemisinin-piperaquine versus Sulfadoxine-pyrimethamine for malaria during pr...
Xiajing Chu
Meixuan Li

Xiajing Chu

and 6 more

March 20, 2020
Abstract Background Malaria in pregnancy is one of the serious global problems of our time. There were wide concerns about IPT-DP versus IPT-SP for prevention of malaria during pregnancy. Objectives To assess the current latest evidence on the efficacy and safety of dihydroartemisinin-piperaquine versus sulfadoxine-pyrimethamine for malaria in pregnancy. Search Strategy The Cochrane Library, EMBASE, PubMed and Web of science were searched from the earliest publication date available to July 4, 2019 Selection Criteria We included randomized controlled trials comparing dihydroartemisinin-piperaquine with sulfadoxine-pyrimethamine for malaria in pregnancy. Data Collection and Analysis Outcomes were analyzed using Risk ratios (RR) and 95% confidence intervals (CI). We did subgroup analysis about different intervals, including 4-6 or 8 weeks. Main Results A total of five studies with 4660 HIV-uninfected pregnant women in area of high malaria-transmission intensity were included in final synthesis. Meta-analysis showed dihydroartemisinin-piperaquine for intermittent preventive treatment resulted in lower rates of placental malaria (RR=0.50; 95%CI, 0.43–0.59) and infection with malaria parasites at delivery (RR=0.05; 95%CI, 0.01–0.24). In the subgroup analysis, dihydroartemisinin-piperaquine for intermittent preventive treatment at 4-6 weeks of administration was associated with a better effect for infection with malaria parasites at delivery. Conclusions Dihydroartemisinin-piperaquine was a promising alternative drug to sulfadoxine-pyrimethamine for intermittent preventive treatment in settings with high sulfadoxine-pyrimethamine resistance, especially at 4-6 weeks of administration. Based on real-world and other epidemiological settings, more data will be needed to identify the risk of adverse effects.
Obstetrics in the time of Coronavirus: A Tertiary Maternity Centre’s Preparations and...
Shau Khng Jason Lim
Joella Ang

Shau Khng Jason Lim

and 10 more

March 20, 2020
Objective Since the outbreak of Coronavirus Disease 2019 (COVID-19) in Singapore in January 2020, our maternity centre at Singapore General Hospital has devised and implemented contingency protocols to manage COVID-19 suspected or infected pregnant mothers. These aimed to deliver effective care while ensuring the safety of our front-line healthcare workers. Methods The epidemiology and pathogenicity of SARS-COV-2 was compared to the Severe Acute Respiratory Syndrome outbreak in 2003. Our protocols were constructed following multidisciplinary discussions. These workflow processes include triage, isolation, determination of admission criteria and subsequent secured transfers to dedicated isolation wards. Intrapartum management policies including mode of delivery were reviewed with the focus on minimising maternal-fetal transmission. Postpartum care (breastfeeding and skin-to-skin contact) policies were re-evaluated. Results The Centre conducted several multidisciplinary in-situ simulations which identified potential latent threats and deficiencies in infection containment. These were gaps in communication and co-ordination between operating theatre, obstetrics and neonatal teams resulting in delayed transfers. A particular vulnerability was the consistent breaches observed in the donning and doffing of personal protective equipment. This led to a need for additional personnel to guide and police strict adherence among healthcare workers. Conclusion Operational readiness leverage on robust contingency protocols which must be subjected to simulation and scrutiny with subsequent revision. We recommend deploying additional supervisory manpower to maintain strict adherence to infection prevention protocols. Effective preparation is key in maintaining high clinical standards of obstetric care while ensuring safety of healthcare workers during this ongoing pandemic. Funding No funding nor conflicts of interest.
A case of pregnant uterine damage when performing operative laparoscopy.
Oleg Volkov

Oleg Volkov

March 20, 2020
A document by Oleg Volkov, written on Authorea.
Management of recurrent pelvic organ prolapse. (Mini-commentary on BJOG-19-1139.R1)
Katie Propst

Katie Propst

March 20, 2020
Mini-commentary on BJOG-19-1139.R1: Mesh inlay, mesh kit or native tissue repair for women having repeat anterior or posterior prolapse surgery: randomised controlled trial (PROSPECT)
Impact assessment of climate change and human activities on wind erosion on the Qingh...
Yanmin Teng
Jinyan Zhan

Yanmin Teng

and 6 more

March 20, 2020
Wind erosion has become one of the major causes of land degradation on the Qinghai-Tibet Plateau (QTP). Assessing wind erosion dynamics is critical to forecast wind erosion and formulate desertification control strategies. In this study, the spatial and temporal variations in wind erosion on the QTP from 1980 to 2015 were evaluated by the revised wind erosion equation (RWEQ). Furthermore, the relative contributions of climate change and human activities to wind erosion were analysed to identify the drivers. The results showed that wind erosion intensity on the QTP increased continuously from southeast to northwest. Areas with moderate or high soil erosion intensity (>25 t∙hm2∙a-1), accounting for 53.48% of the region, were mainly distributed on the western and northern parts of the plateau. The mean annual soil wind erosion modulus (SWEM) of the total region during 1980-2015 was 32.08 t∙hm2∙a-1, with an obvious decline at a rate of approximately 0.14 t∙hm2∙a-1 in this period. However, 9.99% of the study area showed a relatively significant increase, and these areas were mostly located in the northwestern part of the region. Climate change, especially variation in wind speed, was the dominant factor that affected wind erosion over the whole plateau, whereas the impacts of human activities such as grazing and ecological restoration policies and programmes were comparatively small and usually more localized.
NCBI dbRBC database of allelic variationsof genes encoding antigens of blood group sy...
Santosh Patnaik

Santosh Patnaik

March 20, 2020
ABSTRACTAnalogous to human leukocyte antigens, blood group antigens are surface markers on the erythro-cyte cell membrane whose structures differ among individuals and which can be serologically identified. The Blood Group Antigen Gene Mutation Database (BGMUT) is an online repository of allelic variations in genes that determine the antigens ofvarious human blood group systems. The database is manually curated with allelic information collated from scientific literature and from direct submissions from research laboratories. Currently, the database documents sequence variations of a total of 1251 alleles of all 40 gene loci that together are known to affect antigens of 30 human blood group systems. When available, information on the geographic or ethnic prevalence of an allele is also provided. The BGMUT website also has general in-formation on the human blood group systems and the genes responsible for them. BGMUT is a part ofthe dbRBC resource of the National Center for Biotechnology Information, USA, and is available online at  http://www.ncbi.nlm.nih.gov/projects/gv/rbc/xslcgi.fcgi?cmd=bgmut. The database should be of use to members of the transfusion medicine community, those interested in studies of genetic variation and related topics such as human migrations, and students as well as members of the general public.INTRODUCTIONThe BGMUT Blood Group Antigen Gene Mutation Database documents variations in genes that encode antigens for human blood groups. It is a part of the dbRBC resource (1) of the National Center for Biotechnology Information (NCBI) of USA and can be freely accessed online at http://www.ncbi.nlm.nih.gov/projects/gv/rbc/xslcgi.fcgi?cmd=bgmut.Recent documentation of the extent and the surprisingly high numbers of mutations in the human genome have suggested that, perhaps with the exception of identical twins, no two individuals bear exact copies of chromosomal DNA. In those studies, DNA of random subjects is compared but more often phenotypic differences observed in disease states, whether single gene inherited disorders or in association studies of complex conditions are taken as criteria for selection of individuals whose DNA is examined for sequence changes. In the latter studies, large fragments of DNA are usually examined and compared statistically to matched control individuals. Changes in blood group phenotypes are another criterion for selection of subjects who may show differences in sequences of two or more defined sets of genes. These genes encode a group of red cell membrane proteins that are polymorphic in the population and are defined as blood group antigens; in addition, these genes may encode certain glycosyl transferases that are involved in the synthesis of red cell membrane glycans whose structures also differ among individuals. The former group consists of structural molecules, channels, adhesion molecules or enzymes and, excluding their red cell membrane location, can be considered as representative of any human protein, whereas the latter are similar tomost other glycosyl transferases. Evidence suggests that sequence changes in these proteins or even their absence,such as in null phenotypes, is not, in most cases, physiologically harmful. The proteins or the glycans fulfill their role as blood group antigens because they are polymorphic in the population and their sequence changes can be readily predictedby serological approaches; they are known as ‘antigens ’because in the course of transfusion, or pregnancy, the presence of a variant protein epitope is recognized as‘non-self’ and may ultimately result in an adverse immunological reaction. The use of transfusion being ubiquitous in the practice of medicine, populations world-wide are serologically tested and variant antigens and their genes, in contrast to many other variant genes arebeing documented in a large number of diverse populations. Although some variants occur rarely and, may onlybe observed in a single individual or family, others appearin unexpectedly large populations, such as the MiIIIphenotype encoded by the MiIIIGYPAgene, in Taiwan (incidence can be as high as 88% among Ami tribes) (2).For many alleles, the database also provides informationon the geographic or ethnic origin of alleles and/or theirassociated serological phenotypes when such informationwas presented in the publications describing the alleles.  This may be of use to those interested in populationmigrations.HISTORY AND CURRENT STATEBGMUT was developed in 1999 as a locus-specific gene mutation database under the aegis of the HumanVariation Genome Society. It was curated under the direction of one of the authors (OOB) with original information contributed by more than a dozen blood group system experts. The database was hosted online by the Department of Biochemistry at the Albert Einstein College of Medicine, New York. BGMUT was identifiedas one of three model locus-specific databases from morethan 200 in a scholarly review (3). In 2006, BGMUTbecame a part of the dbRBC resource of the NCBI.  At dbRBC, curatorship and direction for maintenanceof the database has been provided by another of the authors (WH). The number of alleles in BGMUT has ap-proximately doubled since 2004 when the database wasfirst described in a scholarly publication (4). This publica-tion has been referred to many times in the scientific literature indicating that BGMUT has been a usefulresource. Links to BGMUT database records are availableon relevant pages of the Wikipedia online encyclopedia,and on many of NCBI’s online resources. BGMUT is alsoa part of the PhenCode project which attempts to integrate genetic variation data with the UCSC Genome Browser (5).As of August 2011, BGMUT had 1251 alleles belongingto 40 genes that are together responsible for 30 humanblood group systems (Table 1). Alleles of some genes, such as ABO and RHCE/D which are, respectively, responsible for the ABO and Rh blood group systemsmost frequently examined in the populations, are morenumerous than those of others (Table 1). As per theInternational Society for Blood Transfusion, there are 30human blood group systems (http://ibgrl.blood.co.uk/ISBT%20Pages/ISBT%20Terminology%20Pages/Table%20of%20blood%20group%20systems.htm), all of whichare covered by BGMUT. The Globoside (GLOB) system iscurrently considered a part of the P1PK system inBGMUT, which additionally considers the system of T and Tn antigens as a separate blood group system.DATABASE ARCHITECTUREBGMUT is accessible online for view, search or for ad-ministration as a website in the form of HTML (hyper-text markup language) pages (Figures 1 and 2).  A Microsoft SQL Server relational database is used fordata storage. Programmatic code in SQL (structuredquery language), C++and XSLT (extensible structuredlanguage transformations) languages is used for inter-action with the SQL Server database and for renderingBGMUT’s web-based interface. Raw data on all or asubset of the alleles described in BGMUT can be down-loaded as tab-delimited or comma-separated (CSV) textformats from the BGMUT website. Compilations ofallelic sequences for the ABO, H, MNS and Rh systemsin the Microsoft Excel format are also available fordownload.DATABASE CURATION AND ALLELE SUBMISSIONThe BGMUT database is curated manually. Allelic information is periodically collated from scientific literature, asis the case for a majority of the alleles listed in BGMUT, or is obtained as direct submissions from researchers through the database website. During the process ofcuration, good quality of methods used in a study is ascertained. The new candidate allele’s sequence that has been published and/or submitted to a publicly available repository such as NCBI’s GenBank is compared to BGMUT’s reference allele for the gene sequence. The sequence positions and the kinds of the deduced aminoacid changes are also verified. Authors are consulted incase of a question or disagreement. For direct submission of information on a new allele for inclusion in the database, a scientific publication describing the allele is not required. However, submitters are encouraged to deposit the allele’s sequence in a publicly available repository. In the absence of a scientific publication, this is arequirement.ALLELES IN BGMUTAlleles in BGMUT are grouped by the blood group system that the genes they belong to affect. For each allele in the database, BGMUT provides details on the nucleotide changes and the deduced amino acid changes in the protein encoded by the gene the allele belongs to. These changes are in context of a ‘reference’ allele that itself is included in BGMUT, and is the same for all alleles of agene. Besides the information on the sequence changes, BGMUT also details for an allele the frequency of occurrence, the associated blood group phenotype, references to the studies that identified and characterized the allele and accession numbers of the relevant sequences in NCBI GenBank when such information is available. GenBank accession numbers, however, are not available for many alleles because though they have been described in published literature, their sequences were not deposited inthe repository by the authors. When known, the regions of the gene or cDNA that were sequenced to identify the allele, the prevalence of the allele in different geographical regions or ethnic populations and association of the allele with diseases are also noted. Often, a name is also provided for an allele. Names make it easier to refer to alleles and can indicate the associated phenotype and/or nucleotide or amino acidvariation. Table 1. Blood group systems in the BGMUT database
NCBI gene expression and hybridization array data repository
Ron Edgar

Ron Edgar

March 20, 2020
ABSTRACTThe Gene Expression Omnibus (GEO) project was initiated in response to the growing demand for a public repository for high-through put gene expression data. GEO provides a flexible and open design that facilitates submission, storage and retrieval of heterogeneous data sets from high-through put gene expression and genomic hybridization experiments.GEO is not intended to replace in house gene expression databases that benefit from coherent data sets,and which are constructed to facilitate a particular analytic method, but rather complement these byacting as a tertiary, central data distribution hub. The three central data entities of GEO are platforms,samples and series, and were designed with gene expression and genomic hybridization experiments in mind. A platform is, essentially, a list of probes that define what set of molecules may be detected. A sample describes the set of molecules that are being probed and references a single platform used to generate its molecular abundance data. A seriesorganizes samples into the meaningful data setswhich make up an experiment. The GEO repository ispublicly accessible through the World Wide Web a thttp://www.ncbi.nlm.nih.gov/geo.BACKGROUNDMolecular biological experiments utilizing high-through puthybridization array- and sequencing-based techniques havebecome extremely popular in recent years (1–3). These tech-niques have been used to measure the molecular abundance ofmRNA and genomic DNA either in absolute or relative terms.Mainly contributing to this popularity is the highly parallelnature of these techniques and the concomitant conservation oftime and resources brought about by the large number ofsimultaneous (or near-simultaneous) molecular samplingevents performed under very similar conditions.For a number of years there has been a growing desire forthese high-throughput data sets to be made publicly availableonce research findings have been published in the scientific literature—similar to journal and public funding requirementsfor the public release of biological sequence data. There have also been calls for the establishment of a public repository for (at least the gene expression microarray subset of) these data sets (4–6),and journals and public funding agencies have begun to makepublic availability of high-throughput data a condition of publication (7) or funding (e.g. NINDS request for proposalsBAA-RFP-NIH-NINDS-01–03, p. 76 at http://www.ninds.nih.gov/funding/2rfp_01_03.pdf), respectively. Recognizing the desire that this data should be made widely available, several laboratories and institutions have constructed primary and secondary Internet resources to distribute these high-throughput data sets(Table 1). Over the last several years, there has been an international effort to catalog the minimal set of information which is necessary in order for microarray experiments to be properly interpreted and to be comparable with one another (6). The codification and publication of this set of guidelines will be invaluable as aguide for high-throughput gene expression and genomic hybridization data producers and data repositories. We feel,however, that over-zealous application of these guidelines insetting standards and requirements must be avoided because it will stifle a rapidly developing and technically challenging field.  Therefore, our primary goal in creating the Gene Expression Omnibus (GEO; http://www.ncbi.nlm.nih.gov/geo) was to attempt to cover the broadest spectrum of high-through put experimental methods possible and remain flexible and responsive to future trends, rather than setting rigid requirements and standards for entry. In taking this approach, however, we recognize that there are obvious, inherent limitations to functionality and analysis that can be provided on such heterogeneous data sets.Hence, GEO is not intended to replace or match primary and secondary resources that operate on homogeneous data sets, but instead to serve as a complementary tertiary resource for the storage and retrieval of public high throughput gene expression and genomic hybridization data.REPOSITORY DESIGN GEO segregates data into three principle components, platform,sample and series (Table 2), each of which is accessioned(i.e. given a unique and constant identifier) in a relational data-base (Fig. 1). To achieve an open and flexible design that allows storage and retrieval of very diverse data types, the data are not fully granulated within the database. Instead, a tab-delimited ASCII table is stored for each platform and each sample. The table consists of multiple columns with accompanying column header names. The data within this table are currently partially extracted for indexing, but may be further extracted for more extensive search and retrieval. In addition, any number of supplementary columns may be provided by the submitter for the inclusion of additional, submitter-defined information.An instance of a platform is, essentially, a list of probes that define what set of molecules may be detected in any experiment utilizing that platform. For example, the platform data table may contain GEO-defined columns identifying the position and biological reagent contents of each probe (spot) such as a GenBank accession number, open reading frame (ORF) name and clone identifier, as well as submitter-defined columns.Platform accession numbers have a ‘GPL’ prefix.An instance of a sample describes the derivation of the set of molecules that are being probed and utilize platforms to generate molecular abundance data. Each sample has one, and only one, parent platform which must be previously defined.For example, a sample data table may contain columns indicating the final, relevant abundance value of the corresponding spot defined in its platform, as well as any other GEO-defined(e.g. raw signal, background signal) and submitter-defined columns. Sample accession numbers have a ‘GSM’ prefix.An instance of a series organizes samples into the meaningful data sets which make up an experiment, and are bound together by a common attribute. Series accession number shave a ‘GSE’ prefix.
Investigating long year gully erosion and its impacts on soil loss, land competition...
Tsegaye Yazie
Mulatie Mekonenn

Tsegaye Yazie

and 3 more

March 20, 2020
This paper investigated the rate of gully formation and development, and its impacts on land competition and crop yield reduction in the Genbo Wonz Watershed, north-west highlands of Ethiopia. Geometrical gully dimension measurements, field observations and satellite imagery assessment have been performed selecting 22 gullies. As a result, road construction and design problems of soil and water conservation practices (SWCPs) were found to be important causes of gully formation and development. The total volume of soil loss from 22 gullies in three decades was ~340, 957 t, changing ~10 ha agricultural land to unproductive land. The annual rate of gully erosion was found to be ~62 t ha-1 with an average gully density of 16.4 m ha-1. Gully erosion also results in loss of 24 t yr-1 Teff grain yield (Eragrostis teff, E. abysainica) and 14 t yr-1 animals forage. To arrest the problem, proper design of SWCPs within farmlands, appropriate runoff discharge mechanisms along roads and controlled grazing systems within the grazing lands ought to be executed.
Long- and short-read metabarcoding technologies reveal similar spatio-temporal struct...
Brendan Furneaux
Mohammad Bahram

Brendan Furneaux

and 4 more

March 20, 2020
Fungi form diverse communities and play essential roles in many terrestrial ecosystems, yet there are methodological challenges in taxonomic and phylogenetic placement of fungi from environmental sequences. To address such challenges we investigated spatio-temporal structure of a fungal community using soil metabarcoding with four different sequencing strategies: short amplicon sequencing of the ITS2 region (300-400 bp) with Illumina MiSeq, Ion Torrent Ion S5, and PacBio RS II, as well as long amplicon sequencing of the full ITS and partial LSU regions (1200-1600 bp) with PacBio RS II. Resulting community structure and diversity depended more on statistical method than sequencing technology. The use of long-amplicon sequencing enables construction of a phylogenetic tree from metabarcoding reads, which facilitates taxonomic identification of sequences. However, long reads present issues for denoising algorithms in diverse communities. We present a solution that splits the reads into shorter homologous regions prior to denoising, and then reconstructs the full denoised reads. In the choice between short and long amplicons, we suggest a hybrid approach using short amplicons for sampling breadth and depth, and long amplicons to characterize the local species pool for improved identification and phylogenetic analyses.
GABOR FACE CLUSTERING USING AFFINITY PROPAGATION AND STRUCTURAL SIMILARITY INDEX
Issam Dagher
Sandy Michael

Issam Dagher

and 2 more

March 19, 2020
Clustering is an important technique in data mining. It separates data points into different groups or clusters in such a way that objects in the same group are more similar to each other in some sense than with the objects in other groups. Gabor face clustering using affinity propagation and structural similarity index is composed of: A representation based on Gabor filters which has been shown to perform very well in face features, Affinity propagation clustering algorithm which is flexible, high speed, and does not require to specify the number of clusters, and structural similarity index which is a very powerful method for measuring the similarity between two images. Experimental results on two benchmark face datasets (LFW and IJB-B) show that our method outperforms well known clustering algorithms such as k-means, spectral clustering and Agglomerative
Out-of-pocket expenditure in a country with universal health coverage: A qualitative...
Isurujith Kongala Liyanage
Dinesha Jayasinghe

Isurujith Kongala Liyanage

and 7 more

March 19, 2020
Abstract Rationale, aims and objectives: Sri Lanka has a well-established government-funded universal health coverage which provides free health care to all citizens. The aim of this qualitative study was to examine the out-of-pocket expenses incurred by patients with cirrhosis during admission to a tertiary care government hospital in Sri Lanka, and the impact such expenses might have on equity of care and patient outcome. Methods This is a qualitative study conducted among patients with cirrhosis admitted to a tertiary-care hospital, their caregivers and physicians. Quota sampling was used until data saturation was achieved. Data was collected through individual interviews and small group discussions using directed and open-ended questions. Thematic framework method was used to analyze data. Out-of-pocket expenses incurred by patients, its impact on equity of patient care and outcome were investigated. Results Costs for laboratory investigations, drugs purchased from the private sector and hired caretakers for hospitalized patients were reported as direct expenses. Loss of work and other sources of income were the primary indirect expenses. The impact of such expenses was higher in patients and families from lower socioeconomic categories, especially among those who were dependent on a daily income. Health care workers actively tried to minimize these out-of-pocket expenses, resulting in choice on investigations, drugs and other interventions often being made by the clinician and occasionally not being discussed with the patient, resulting in poor patient satisfaction. Conclusion This study reveals a substantial direct and indirect economic impact on patients despite being cared for in a government hospital with universal health coverage. The impact was more in patients from lower socioeconomic strata, potentially resulting in inequity in the care provided as well as the health outcomes.
Physical Properties of Amazon Fats and Oils and their Blends
Ericsem Pereira

Ericsem Pereira

and 5 more

March 19, 2020
1. IntroductionThe Brazilian Amazon region is rich in oleaginous plant species. Vegetable oils and fats produced by these species have unique compositions, as well as physicochemical and nutraceutical properties (Bezerra, Rodrigues, de Oliveira, da Silva, & da Silva, 2017). In fact, species such as the palm tree (Elaeis guineensis ) are economically important for the region since they are widely used in the food and pharmaceutical industries (Edem, 2002). However, the great demand for natural oils and fats has brought attention to other matrices.The seed of Brazil nut tree (Bertholletiaexcelsa ) is considered one of the major economically and industrially relevant Amazonian seeds, presenting a high content of unsaturated fatty acids, which provides its oil with interesting nutritional characteristics (Chunhieng, Hafidi, Pioch, Brochier, & Didier, 2008).Murumuru (Astrocaryum murumuru ) is a native plant from the Amazon forest; its nuts present an exceptionally high oil content, around 40%, with a beneficial fatty acids (FA) ratio of ω3:ω6,attracting the interest of the fats and oils industry (Pereira Lima et al., 2017).Tucuma (Astrocaryum vulgare ) is also a native species, from north and northeast of Brazil, with fruits consisting of two main oleaginous fractions, the pulp and the kernel. While the pulp produces an orange oil rich in polyunsaturated FA, the kernel produces a fat rich in lauric and myristic acid (Bora, Narain, Rocha, De Oliveira Monteiro, & De Azevedo Moreira, 2001).Bacuri (Platonia insignis ), another Amazonian vegetable matrix, produces fruits composed of three main fractions: pulp, shell, and seed. The pulp can be consumed with either raw or processed foods such as juices, ice cream and jams. While the composition of bacuri fruit pulp oil has already been evaluated in the literature (Hiane, Bogo, Ramos, & Ramos Filho, 2003), a study of the composition and physical properties of the fat extracted from their seeds has not been subject of any previous report.Pracaxi (Pentaclethramacroloba ) is a northern Brazilian oil seed plant. Its fruits contain 4 to 8 seeds from which oil is extracted. This oil has a high content of ω6 and ω9 FA, and is considered a natural source of behenic acid (Pereira Lima et al., 2017).Patawa (Oenocarpusbataua ) is a lesser known palm tree from the Amazon region. The oil extracted from its pulp has a healthy FA content, presenting a ratio of 18.5/81.5 (w/w) saturated/unsaturated FA (A. M. da C. Rodrigues, Darnet, & Silva, 2010).Characterization of the physical properties of these fats and oils is essential in order to promote their industrial application. These properties are in general directly related to the lipids’ triacylglycerol (TAG) composition. Furthermore, determining technological aspects, such as melting and crystallization profiles, are also quite important to develop fat-based food products (Walstra, Kloek, & van Vliet, 2001). In this context, blends of fats and oils are interesting alternatives for broadening industrial applications of Amazon fats and oils, building specific physicochemical characteristics and thermal behaviors.Given the demand for new fats and oils, and the scarce amount of research on physical properties of Amazon oils, this study was aimed at the characterization of physical and physicochemical properties of six vegetable fats and oils: murumuru fat, bacuri fat, tucuma kernel oil, patawa oil, pracaxi oil, and Brazil nut oil, correlating them with their triacylglycerol (TAG) profiles. Melting and crystallization behavior of multiple blends was also investigated in order to identify potential applications.
CaMKII activation and necroptosis augment in diabetic cardiomyopathy via a RIPK3-depe...
Yun Chen
Xinshuai Li

Yun Chen

and 7 more

March 19, 2020
Background and Purpose Activation of Ca2+/calmodulin-dependent protein kinase (CaMKII) has been proved to play a vital role in cardiovascular diseases. Receptor-interaction protein kinase 3 (RIPK3)-mediated necroptosis is crucially participated in cardiac dysfunction. The study aimed to investigate the effect as well as mechanism of CaMKII activation and necroptosis on diabetic cardiomyopathy (DCM). Experimental Approach Primary cardiomyocytes were treated with AGEs (200 μg/mL) for 24 h. Cell injury, CaMKII activity and necroptosis were detected. Wild type (WT) and the RIPK3 gene knockout (RIPK3-/-) mice were intraperitoneally injected with 60 mg/kg/d streptozotocin (STZ) for 5 consecutive days. After 12 w feeding, 100 μL recombinant adenovirus solution carrying I1PP1 gene were injected into the caudal vein of mice. Echocardiography, myocardial injury, CaMKII activity, necroptosis, RIPK1 expression, MLKL phosphorylation, mitochondrial ultrastructure were measured. Key Results Cardiac dysfunction, CaMKII activation and necroptosis were aggravated in streptozotocin (STZ) stimulated mice, as well as in (Lepr) KO/KO (db/db) mice. RIPK3 deficiency alleviated cardiac dysfunction, CaMKII activation and necroptosis in DCM. Cell injury, CaMKII activation and necroptosis were augmented in advanced glcation endproducts (AGEs)-stimulated cardiomyocytes, which was attenuated after RIPK3 down-regulation. Furthermore, inhibitor 1 of protein phosphatase 1 (I1PP1) over-expression reversed cardiac dysfunction, myocardial injury and necroptosis augment, and CaMKII activity enhancement in WT mice with DCM, but not in RIPK3 knockout mice with DCM. Conclusion and Implications CaMKII activation and necroptosis augment in DCM via a RIPK3-dependent manner, which may provide therapeutic strategies for DCM.
¬The Effect of Immunomodulatory Diet (Omega-3 Fatty Acid, γ-Linolenic Acid and Antiox...
Mahsa Malekahmadi
Naseh Pahlavani

Mahsa Malekahmadi

and 6 more

March 19, 2020
Enteral immunomodulatory nutrition is suggested as an adjuvant therapy for patients admitted in intensive care units (ICU), but its effectiveness remains debated. The aim of this systematic review and meta-analysis is to examine the effect of dietary immunomodulatory formula on the clinical outcomes and risk of overall mortality in critically ill patients. PubMed, Scopus and ISI web of Knowledge databases were searched until September 2019. Randomized Controlled Trials (RCTs) that used immunomodulatory diet containing omega-3 fatty acid, γ-linolenic acid and antioxidants in ICU were included. Ten RCTs including 1166 participants were included in the meta-analysis. Immunomodulatory diet containing omega-3 fatty acid, γ-linolenic acid and antioxidants led to significantly reduce the duration of ICU stays (WMD: −2.97 days; 95%CI: -5.59, -0.35), duration of mechanical ventilation (WMD = -2.20 days, 95%CI: -4.29, -0.10), SOFA (sequential organ failure assessment) and MOD (multiple organ dysfunction) score (Hedge’s g: -0.42 U/L; 95% CI: -0.74, -0.11). The 28 days’ overall mortality was remarkably decreased following Immunomodulatory supplement in critically ill patients (RR = 0.74, 95% CI: 0.58, 0.91) and extended the ICU- free days (WMD: 4.06 days, 95%CI: 0.02, 8.09). However, immunomodulatory formula had no significant effect on length of hospital stays, ventilator- free days and level of oxygenation.Immunomodulatory diet containing omega-3 fatty acid, γ-linolenic acid and antioxidants might have beneficial effects for the patient’s residing in ICU; However, further well-designed RCTs with larger sample size are recommended to confirmed its effect.
When life hands you lemons, make lemonade: Adapting undergraduate clinical medical ed...
Mingyue Li
Xinyi Li

Mingyue Li

and 2 more

March 19, 2020
Manuscript title:Adapting medical education to COVID-19 pandemic: Singapore’s experienceAuthors:Dr Li Xinyi, MRCOG, Senior Resident, Department of Obstetrics and Gynaecology, KK Women’s and Children’s Hospital, SingaporeDr Li Mingyue, MBBS, Resident, Department of Obstetrics and Gynaecology, KK Womens’s and Children’s Hospital, SingaporeDr Rajeswari Kathirvel, FRCOG, Consultant, Department of Obstetrics and Gynaecology, KK Women’s and Children’s Hospital, Singapore. Adjunct Assistant Professor, Lee Kong Chian School of Medicine and National University of Singapore, SingaporeCorresponding author:Dr Li Mingyue, MB.BS, Resident, Department of Obstetrics and Gynaecology, KK Women’s and Children’s Hospital, SingaporeEmail: mingyue.li@mohh.com.sgTelephone: +65 81385685Ever since the first case of COVID-19 was reported in Singapore on 23 January 2020, the number of cases have increased dramatically. In view of the unpredictable nature of this unknown virus and having learnt valuable lessons from the SARS epidemic in 2003, Singapore authorities took the decision to raise the nation’s Disease Outbreak Response System Condition (DORSCON) 1 level from yellow to orange on 7 February 2020. This indicates that COVID-19 is considered a severe disease which spreads easily from person to person, but has not spread widely in Singapore, and is presently being contained. As of 13 March 2020, there was a total of 187 confirmed cases, with 91 active cases.2 To ensure the timely containment of the disease and prevent uncontrolled spread within the community and amongst healthcare workers, strict measures have been taken to manage the flow of visitors entering any healthcare institution and also to restrict the movement of staff and patients between various healthcare institutions unless in extenuating circumstances. All non-essential meetings have been cancelled or moved online to further reduce risks.Unsurprisingly, clinical postings for the medical students have also been suspended, much to the distress of the Lee Kong Chian School of Medicine (LKC) Year 4 students, who were about to start their clinical posting in Obstetrics and Gynaecology (OBGYN) on 10thFebruary 2020 at KK Women’s and Children’s Hospital (KKH), Singapore. Fortunately, this distress was temporary as the curriculum planning committee promptly got together to find an alternative way of proceeding with the clinical posting without any direct patient contact whilst ensuring that all the learning objectives and the formative assessment criteria are met.The traditional LKC OBGYN curriculum included core sessions that covered the theoretical part of the learning outcomes in an interactive manner. The students were then rotated through the outpatient/inpatient areas, labour ward (LW) and operating theatres (OT). They were expected to complete a list of workplace based assessments including case logs; partograms; direct observation of procedure skills (DOPS) evaluation for speculum examination and Mini-Clinical Evaluation Exercise (Mini-CEX). They were also expected to have observed at least one normal vaginal delivery and a few surgical procedures during their postings.We explain here how we managed to achieve these learning objectives without the students’ actual presence in KKH.An online virtual classroom (Google©) was created with all the students, administrators and the clinical leads to disseminate the schedules, clinical case scenarios and assignments. In order to ensure effective = and timely communication, a chat group consisting of the curriculum planning committee and LKC student representatives was set up. Detailed briefing was sent out to the tutors to inform them of the changes in curriculum delivery format.Core sessions: These were conducted through the web-based video conferencing tool (ZOOM©) that has the advantage of screen sharing and interaction between the tutors and students.“Clerking the expert patient”: Various clinical scenarios were posted on the virtual classroom on a regular basis. Standardised patient (SP) script for these scenarios were sent to the tutors. This allowed the medical students to elicit history from the clinician SPs following which case-based discussions were conducted through ZOOM©. This simulated patient encounter gave students the chance to practice targeted history taking, formulation of differentials and management plans and allowed an opportunity to complete their Mini-CEX evaluations.Virtual OT posting: Live surgery was streamed online through ZOOM© with patient’s consent along with voiceover by clinicians to allow the students to get a close-up view of the ongoing surgeries and enabling them to observe the required procedures.Virtual LW posting: Live video streaming of the LW showed the ward set-up to the students. The learning objectives for the LW posting were met through clinical scenarios discussion via ZOOM© and clinicians used videos to demonstrate various modes of delivery.The DOPS requirement was achieved by the students demonstrating their examination technique on mannequins at LKC premises with the tutors assessing this from KKH through ZOOM©.Formative assessments of clinical knowledge was done through weekly single best answer assignments. These were published and completed online through the Google classroom platform.Having successfully completed our first online OBGYN posting in the current COVID-19 environment, we have gathered feedback from our students to look at areas for improvement that could be applied to the next batch of medical students who will be embarking on their posting shortly. As much as we all agree that clinical postings and direct patient interaction could never be underestimated or replaced, in unique circumstances like this, we need to look into alternative methods like those described above to replace the traditional clinical teaching.Novel portions of this curriculum such as the virtual OT experience has been very well received and the students have requested for it to be incorporated into the regular curriculum even after the clinical postings have resumed. This experience has allowed us to build a blueprint for medical education locally which can be applied to any extraordinary circumstances that requires suspension of clinical postings, like this COVID-19 pandemic. In addition, given the global spread of COVID-19, it is expected that medical schools worldwide will have to start suspending clinical postings as part of infection control measures. By publishing our team’s experience, we hope that educationists worldwide will be able to smoothly transit their clinical curriculum to online learning using ours as a reference.There is no doubt that since the arrival of COVID-19 in Singapore and internationally, life as we know it has been thrown into disarray in some form or another. It is heartening to see the international healthcare community rallying together as we react rapidly on the frontline to institute precautionary measures, publish travel advisories, invent diagnostic kits and develop vaccines and treatment. However, we must not forget that in times of pandemics, other aspects of life must go on. This includes the need for medical education to continue so that we can train our next generation of doctors well to equip them with the knowledge, skills and tenacity to deal with the next abominable pathogen which is lurking in the dark and waiting to strike. COVID-19 is not the first virus that has reached epidemic proportions and will not be the last3. What matters is as educationists, we have to balance the challenges of continuing medical education4 and strive to restore a certain degree of normalcy in our students’ postings by harnessing technology widely used in social and business platforms to aid in their learning. In this way, learning can be maximised without compromising on student or patient safety.As Mr Bill Gates expressed in his opening statement in “Responding to COVID-19- A Once-in-a-century pandemic?” published in the New England Journal of Medicine5, medical educationists share the “same responsibilities of solving the immediate problem and keeping it from happening again”, albeit in a slightly different perspective. This pandemic has revealed the vulnerability of our clinical curriculum and the downstream impact it could potentially have on our medical students and healthcare community. It is imperative that educationists adapt quickly to provide alternatives to clinical postings and learn from these experiences to ensure that the next time something of comparable scale hits us, we will be equipped with a functional Plan B.ReferencesWhat do the different DORSCON levels mean. A Singapore Government Agency Website, 6 Feb 2020. https://www.gov.sg/article/what-do-the-different-dorscon-levels-meanCoronavirus disease 2019: Cases in Singapore. A Singapore Government Agency Website, 13 March 2020. https://www.gov.sg/article/covid-19-cases-in-singaporeMadhav N, Oppenheim B, Gallivan M, et al. Pandemics: Risks, Impacts, and Mitigation. In: Jamison DT, Gelband H, Horton S, et al., editors. Disease Control Priorities: Improving Health and Reducing Poverty. 3rd edition. Washington (DC): The International Bank for Reconstruction and Development / The World Bank; 2017 Nov 27. Chapter 17. Available from: https://www.ncbi.nlm.nih.gov/books/NBK525302/ doi: 10.1596/978-1-4648-0527-1/pt5.ch17Lim EC, Oh VM, Koh DR, et al. The challenges of “continuing medical education” in a pandemic era. Ann Acad Med Singapore. 2009 Aug;38(8):724-6Gates B. Responding to COVID-19- A Once-in-a-Century pandemic? N Engl J Med. 2020 Feb 28. doi: 10.1056/NEJMp2003762
Comparison of long-term outcomes of minimally invasive surgery versus open radical hy...
Jun  Liu
Ting  Chen

Jun Liu

and 8 more

March 19, 2020
BACKGROUND The use of minimally invasive surgery (MIS) for cervical cancer remains controversial. OBJECTIVES To compare the long-term outcomes after experiencing the MIS robot-assisted laparoscopic radical hysterectomy (RRH) and total laparoscopic radical hysterectomy (LRH)) with traditional total open radical hysterectomy (ORH). SEARCH STRATEGY Five electronic databases including PubMed and Embase were searched from inception to January, 2020. SELECTION CRITERIA We included eligible studies of cervical cancer patients with outcomes of MIS and ORH. DATA COLLECTION AND ANALYSIS The pooled hazard ratio (HR) or relative risk (RR) and its 95% confidence interval (CI) of overall survival (OS), disease-free survival (DFS), progression-free survival (PFS) and recurrence (R) were pooled. MAIN RESULTS 37 studies (20,133 patients) were included. Overall, patients in MIS group showed similar prognosis with those in ORH group (OS HR = 1.11, P = 0.350; DFS HR = 1.08, P = 0.426; PFS HR = 1.04, P = 0.873; recurrence RR = 0.91, P = 0.166). For those with early stage cervical cancer, the ORH might be a better prognostic factor for OS than MIS (HR = 1.30, 95% CI: 1.08 - 1.56, P = 0.005), but no significant difference was observed for DFS, PFS and recurrence (P were 0.364, 0.760 and 0.349, respectively). The OS for LRH and RRH comparable to ORH (HR: 1.26 vs. 1.30, P interaction = 0.925). CONCLUSIONS We found that MIS, irrespective of LRH or RRH, might be a poor prognosis factor for early cervical cancer patients in OS compared to conventional ORH.
Probability of severe postpartum hemorrhage in repeat cesarean deliveries: a multicen...
Lili Du
Ling  Feng

Lili Du

and 24 more

March 19, 2020
Objective: The aim of this study was to determine the factors predicting the probability of severe postpartum hemorrhage in women undergoing repeat cesarean delivery. Design: This multicenter, retrospective cohort study based on data from 11 public tertiary hospitals within 7 provinces of China. Setting: 11 public tertiary hospitals within 7 provinces of China. Population: 11074 eligible pregnant women who had a history of cesarean delivery and undergo cesarean delivery again after 28 weeks of gestation. Methods: The cohort was divided into the development and validation sets. The all-variables model and the multivariable logistic regression model (simple model) were fitted to estimate the probability of severe postpartum hemorrhage. Results: Six independent risk factors of severe postpartum hemorrhage in the simple model were selected from 40 clinical information features including a history of endometrial injury, complications with placenta previa or placenta accreta, lower gestational age at delivery, pelvic adhesion, and previous uterine incision status. Our final simple model showed excellent discrimination and calibration, with areas under the ROC curve of more than 0.90 in the validation set. Conclusions: Predictive tools based on patient clinical characteristics can be used to accurately estimate the probability of severe postpartum hemorrhage in patients undergoing repeat cesarean delivery. Funding National Key R&D Program of China (No. 2016YFC1000405 and 2017YFC1001402) and the National Natural Science Foundation (No. 81830045, 81671533 and 81571518). Keywords repeat cesarean deliveries; severe postpartum hemorrhage; placenta previa; placenta accrete; pelvic adhesion; prediction; obstetrics
Development and psychometric properties tool for choosing of a prenatal care provider
Fatemeh Nahidi
Mahboubeh Hajifoghaha

Fatemeh Nahidi

and 3 more

March 19, 2020
The aim of this study was to design a decision-making questionnaire for selection of prenatal care provider and determine its psychometric properties. Design: The present study is a mixed-method exploratory research Setting: Three maternity hospitals in Shiraz, Iran. Population: In a sample of 300 low-risk pregnant women, we examined the factor structure, reliability, and validity of the CPCP. Methods In the qualitative phase, were selected 23 pregnant women as well as 10 midwives and gynecologists. The samples sat a semi-structured individual interview. In the next step, the questionnaire items were designed based on the results of the qualitative phase and a review literature. In the quantitative phase, face validity, content validity, construct validity, internal consistency and stability were used to investigate the psychometric properties of the CPCP-60 questionnaire. Results: developed questionnaire consisted of 74-item which were reduced to 60 items after the face and content validity was determined qualitatively and quantitatively. The Exploratory factor analysis results revealed the professional skills, communication skills, personal characteristics of prenatal care providers, and characteristics of pregnancy and childbirth centers which accounted for 60.52% of the total variance. Cronbach’s alpha coefficient (0.947) and test-retest (0.951) indicated excellent internal consistency and stability of the questionnaire. Conclusion: Since the designed questionnaire of CPCP-60 is a valid and reliable instrument commensurate with the cultural conditions of society, it can be used in research and clinical settings to assess the pregnant women’s decision making for selection of prenatal care providers in Iran.
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