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Methodological assessment of Mexican Clinical Practice Guidelines: Critical appraisal...
Luis Colunga-Lozano
Vilma  Gerardo-Morales

Luis Colunga-Lozano

and 12 more

January 16, 2020
Background and Objective Clinical Practice Guidelines (CPGs) provide evidence-based recommendations to healthcare professionals, policy makers, patients and other stakeholders. Mexico is the biggest producer of CPGs in Latin America and Caribbean countries. The National Healthcare Technology Excellence Center (acronym in Spanish: CENETEC) is responsible for the CPG development, adaptation and update. The aim of this study was to assess the Mexican CPG quality and adherence to the GRADE framework. Study design We conducted a descriptive cross-sectional study of 86 CPGs representing all the CPGs produced by CENETEC between 2015 and 2017 and published in an online database called “Catalogo Maestro”. We performed quality assessment with the online AGREE II tool and assessed the reporting on the GRADE framework. Results Of the 86 CPGs, 34 were published in 2015, 21 in 2016 and 31 in 2017. The overall quality by AGREE II proved a median of 16.6% (Min 16.6%, Max 50%). Of the 86 CPGs, 25 (29%) used the GRADE framework; adherence to GRADE standards was, however, inconsistent and generally poor. Conclusion CPGs produced by CENETEC during this period had a low score by AGREE II standards and low adherence to the GRADE framework. A concerted initiative could rapidly improve CENETEC guidelines.
Projecting species loss and turnover under climate change for Chinese tree species
liguoqing
Jinghua Huang

liguoqing

and 2 more

January 16, 2020
Climate-change-induced habitat loss will be the largest global threat to biodiversity. Here, we projected species turnover and loss for Chinese tree species under four climate change scenarios. The results show that many trees will be seriously threatened. On average across climate scenarios, about 57% or 23% of the trees would be vulnerable or threatened under no migration assumption or universal migration by 2070, respectively. Projection of species loss and turnover in grid cells indicates considerable variation across climate change scenarios (20%–30% and 40%–65%, respectively) and across geographical regions (25.4%–58.1% and 40.6%–78.8%, respectively). Notably, local extinction risks for Chinese trees species may be high; even under the most conservative situation (lowest emission scenario with universal migration), 18% trees will still be vulnerable or threatened. We suggest that a further studying trees adaptation strategy to climate change is required to ensure the sustainable development of China’s forests.
Projeto de Pesquisa "Museus, Monumentos e Comunidades: Lugares de Memória Pública"
Michel Kobelinski

Michel Kobelinski

January 16, 2020
Proponente: Michel KobelinskiInstituição: Universidade Estadual do Paraná - UNESPARCNPJ: 05012896/0001-42 Área de Estudo - Grandes Áreas do Conhecimento (CNPq)Grande Área 7. Ciências humanas - 7.05.00.00-2 - História  Desenho: História Pública e História Oral (métodos) KOBELINSKI, Michel. Museus, Monumentos e Comunidades: Lugares de Memória  Pública.  Projeto de pesquisa. UNESPAR – Campus União da Vitória, União da Vitória, 2019.Aprovação em Comitê de Ética - Plataforma Brasil (Figura 1)
Corrosion Studies on XD3 Reinforced Concrete Samples Prepared by Using Calcium Nitrat...
Shaymaa Abbas Abdulsada
Richard Bak

Shaymaa Abbas Abdulsada

and 3 more

January 16, 2020
A document by Shaymaa Abbas Abdulsada. Click on the document to view its contents.
Enhancement of Mechanical Properties of Medium Carbon Steel by Formation of Ultra- fi...
Sherif Ali
Ahmed Shash

Sherif Ali

and 5 more

January 16, 2020
In this work, ultra-refined bainitic structures are obtained in medium carbon steel through control of alloy design (Si and Al content) and low temperature isothermal bainitic transformation heat treatment. The chemical design of the steel was modified by using varying Al ratios and the steel was heat treated by isothermal transformation. The tensile strength and ductility were found to improve significantly, and this was owed to modification of the cementite morphology from plate-like to spheroidal morphology. In addition, grain refinement was achieved by fine bainitic structures generated through the heat treatment process. This new technology will have promising results to the steel industry in terms of saving time and energy, enhancing the mechanical properties and reducing the total production cost.
Gli sviluppi tecnologici e la caratterizzazione degli odori ambientali: il naso elett...
Manuele Naddeo

Manuele Naddeo

January 16, 2020
Le tecniche per la caratterizzazione degli odori possono essere di diverso tipo, ciascuna delle quali gode di punti di forza e di debolezza. All'interno di tale scenario, la realizzazione di un vero e proprio naso elettronico in grado di percepire l’emissione odorigena così come la percepirebbe l’olfatto umano, segna l'inizio di una svolta. Chiaramente questo strumento è oggetto di continui studi e migliorie, che possono essere implementate grazie alla ricerca e al progresso tecnologico. Tale dispositivo potrà offrire una caratterizzazione oggettiva e continua degli odori, con un mercato che interesserà i settori sanitari, medici, alimentari, e non solo.
Age of European silver eels during a period of declining abundance in Norway
Caroline  Durif
Ola Diserud

Caroline Durif

and 8 more

January 16, 2020
The European eel (Anguilla anguilla) is critically endangered throughout its distribution range. Knowledge about age distribution of future spawners (silver eels) is essential to monitor the status and contribute to the recovery of this species. Determination of age in anguillid eels is challenging, especially in eels from the northern part of the distribution area where growth is slow and age at maturation can be up to 30 years or more. Eels from the river Imsa in Norway have been monitored since 1975 and this reference time-series has been used to assess the stock at the European level. Population dynamics in this catchment were analyzed during the late 1980s by estimating ages on whole cleared otoliths. However, techniques for revealing annual increments on otoliths have evolved over the years sometimes yielding significant differences in age estimates. In this study, the historical otolith data were reanalyzed using a grinding and polishing method rather than reading the whole otolith. The new age estimates were considerably higher than the previous ones, sometimes by up to 29 years. Since the 1980s, mean age of silver eels only slightly increased (from 19 to 21 years in the 2010s). This was mainly due to the disappearance of younger silver eels (less than 15 years) in the 2010s. The new age estimates agreed with the steep decline in recruitment which occurred in the late 1980s in the Imsa catchment. Growth (30 mm y-1) has not changed since the 1980s, although density in the catchment has decreased. Revealing and reading age of slow growing eels remain a challenge but adding a measure of otolith reading uncertainty may improve age data collection and contribute to recovery measures for this species.
Marine turtles are not sexually size dimorphic, a pattern that is distinct from non-m...
Christine Figgener
Joseph Bernardo

Christine Figgener

and 2 more

January 16, 2020
Turtles have been prominent subjects of analyses of sexual size dimorphism (SSD) owing to their mating system and habitat diversity. In prior studies, marine turtles were grouped with non-marine aquatic turtles (NMAT). This is odd because it is well-established that the marine environment imposes a distinct selective milieu on body form of vagile vertebrates, driven by convergent adaptations for energy-efficient propulsion and drag reduction. We generated a comprehensive database of adult marine turtle body size (38,569 observations across all species), which we then used to evaluate both the magnitude of SSD in marine turtles and how it compares to SSD in NMAT. We find that marine turtles are not sexually size dimorphic, whereas NMAT typically exhibit female-biased SSD. We argue that the reason for this difference is the sustained long-distance swimming that characterises marine turtle ecology, which entails significant energetic costs incurred by both sexes. Hence, the ability of either sex to allocate proportionately more to growth than the other is likely constrained, meaning that sexual differences in growth and resultant body size are not possible. Consequently, lumping marine turtles with NMAT dilutes the statistical signature of different kinds of selection on SSD and should be avoided in future studies.
La nuova era del trattamento delle acque reflue: l'eMBR è la tecnologia del futuro?
Sara Angela Cantarella

Sara Angela Cantarella

January 16, 2020
Da qualche decennio la comunità scientifica è impegnata nella ricerca delle tecnologie più adatte alla rimozione dei cosiddetti contaminanti emergenti dagli effluenti degli impianti di trattamento delle acque reflue esistenti. Tali impianti, infatti, non sono stati progettati per la rimozione di questi microinquinanti di recente scoperta e non si rivelano quindi efficienti in tal senso. Sono numerose le tecnologie che si stanno studiando a scala di laboratorio e tra queste vi è quella che prevede la combinazione di processi elettrochimici e filtrazione su membrana: la tecnologia eMBR, la quale sembra inserirsi bene nel contesto del trattamento delle acque reflue nei prossimi anni considerando i notevoli risultati ottenuti in termini di rimozione di specifici inquinanti e di upgrade di tecnologie sperimentate.   
Clay mineralogy controls SOM formation efficiency via discriminative protection
Bin Zhang
kai liu

Bin Zhang

and 11 more

January 15, 2020
Soil organic matter (SOM) is formed through partial decomposition and transformation of plant litter inputs. Thus, litter chemistry is generally regarded as the primary control over the formation efficiency of litter-derived SOM through selective preservation of recalcitrant litter fractions. Here we used model soils and showed that the SOM formation efficiency was, instead, controlled by discriminative protection of litter- and microbially-derived residues by different clay minerals. The SOM formation efficiency was higher for vermiculite than for kaolinite and illite because vermiculite protected more labile litter- and fungal residues through surface adsorption than did kaolinite or illite through pore entrapment. We developed a novel model to quantify mineral-protection strength following litter decomposition, and demonstrated that the mineral-protection strength explained well the variation in the SOM formation efficiency among the model soils, and could be predicted for a natural soil material from those of its compositional clay mineral types and their relative abundances in the soil. Our results provide solid evidence that soil clay mineralogy plays a critical role in SOM formation as known in long-term SOM stabilization, with important implications for model improvement to predict SOM dynamics for different soil types.
Effects of heterocyclic ring and amino-ethyl-amino group on the electronic and photop...
Jieqiong Yang
Dongzhi Liu

Jieqiong Yang

and 7 more

January 15, 2020
Introduction of a heterocyclic ring and an amino-ethyl-amino group to D-A type photosensitive dyes can modulate the lifetime of the charge separation generated in the D-A dyes as well as their electronic and UV-Vis absorption properties. Here we performed DFT and TDDFT calculations to study eleven derivatives of a triphenylamine-pyrimidine, MTPA-Pyc, in order to improve the performance of MTPA-Pyc as solar cell sensitizers. Five heterocyclic rings and an amino-ethyl-amino group were introduced on the styryl moiety of MTPA-Pyc. The results show that introduction of heterocyclic rings generally causes an absorption red-shift, but absorption intensity is reduced due to the increase of dihedral angle between the donor and acceptor. Further introduction of an amino-ethyl-amino group to these dyes with a heterocyclic ring modification disrupts the conjugation between donor and acceptor, which does not benefit the absorption but may have potential to increase the lifetime of charge separation of the dyes. This work identified two out of eleven dyes that have the best potential for solar cell applications.
No evidence of sickness behaviour or diet selectivity in immune-challenged field cric...
Clint Kelly
Jules Mc Cabe Leroux

Clint Kelly

and 1 more

January 15, 2020
Sickness behaviour is a taxonomically-widespread coordinated set of behavioural changes that in- creases shelter-seeking while reducing levels of general activity, as well as food (anorexia) and water (adipsia) consumption, when fighting infection by pathogens and disease. The leading hypothesis ex- plaining such sickness-related shifts in behaviour is the energy conservation hypothesis. This hypothe- sis argues that sick (i.e. immune-challenged) animals reduce energetic expenditure in order have more energy to fuel an immune response, which in some vertebrates, also includes producing an energetically- expensive physiological fever. We experimentally tested the hypothesis that an immune-challenge with lipopolysaccharide (LPS) will cause Gryllus firmus field crickets to reduce their activity, increase shelter- use and avoid foods that interfere with an immune response (i.e. fat) while preferring a diet thats fuel an immune response (i.e. protein). We found little evidence of sickness behaviour in Gryllus firmus as immune-challenged individuals did not reduce their activity or increase their shelter-seeking. Neither did we observe changes in feeding or drinking behaviour nor a preference for protein or avoidance of lipids. Males tended to use shelters less than females but no other behaviours differed between the sexes. The lack of sickness behaviour in our study might reflect the fact that invertebrates do not possess energetically-expensive physiological fever as part of their immune response. Therefore, there is little reason to conserve energy via reduced activity or increased shelter use when immune-challenged.
Rapid multi-component phase-split calculations using volume functions and reduction m...
Mohamad Fathi
Stefan Hickel

Mohamad Fathi

and 1 more

January 14, 2020
We present a new family of fast and robust methods for the calculation of the vapor-liquid equilibrium at isobaric-isothermal (PT-flash), isochoric-isothermal (VT-flash), isenthalpic-isobaric (HP-flash), and isoenergetic-isochoric (UV-flash) conditions. The framework is provided by formulating phase-equilibrium conditions for multi-component mixtures in an effectively reduced space based on the molar specific value of the recently introduced volume function derived from the Helmholtz free energy. The proposed algorithmic implementation can fully exploit the optimum quadratic convergence of a Newton method with the analytical Jacobian matrix. This paper provides all required exact analytic expressions for the general cubic equation of state. Computational results demonstrate the effectivity and efficiency of the new methods. Compared to conventional methods, the proposed reduced-space iteration leads to a considerable speed-up as well as to improved robustness and better convergence behavior near the spinodal and coexistence curves of multi-component mixtures, where the preconditioning by the reduction method is most effective.
Quantifying the Uncertainty of the Future Hydrological Impacts of Climate Change: an...
Jiali Ju
Heng Dai

Jiali Ju

and 8 more

January 14, 2020
The comparison and quantification of different uncertainties of future climate change involved in the modeling of a hydrological system are highly important for both hydrological modelers and policy-makers. However, few studies have accurately estimated the relative importance of different sources of uncertainty involved in climate change predictions. In this study, an advanced hierarchical uncertainty analysis framework incorporated with a variance-based global sensitivity analysis, was developed to quantify different sources of uncertainty in hydrological projections under climate change. The uncertainties considered in this research are from greenhouse gas emission scenarios (GGES), global climate models (GCMs), hydrological models (Xinanjiang and variable infiltration capacity (VIC) models) and hydrological parameters, and this new methodology was implemented in a humid subtropical basin in southern China. The results indicated that the GCMs and hydrological parameters (GGESs) are the main (least) contributor of uncertainty in the discharge projections at the interannual scale. At the intra-annual scale, GCMs contribute the largest uncertainty of the discharge predictions during summer season, whereas the uncertainty due to GGESs, hydrological model and parameters is generally larger in winter. It was also found that although there is a strong temporal and spatial variability of general sources of uncertainty, this heterogeneity does not affect the importance of uncertainty sources. This study provides a better understanding of the uncertainty sources in hydrological predictions in the context of climate change. And the uncertainty analysis framework used is mathematically rigorous and can be applied to a wide range of climate and hydrological models with different uncertainty sources.
Analysis of Mortality Risk Following Receipt of Implantable Cardioverter/Defibrillato...
James Caffrey
CHO-KAI WU

James Caffrey

and 3 more

January 14, 2020
ABSTRACT Rationale , aims, and objectives: Patients covered by the Taiwan National Health Insurance (NHI) program are eligible to receive an implantable cardioverter/defibrillator (ICD) if they had heart failure (HF) or were determined to be at high risk of sudden cardiac death (SCD). The aim of the study was designed to evaluate ICD recipient prognoses with respect to contributory risks. Methods: From the NHI research database, 2194 patients in Taiwan who received an ICD during the 11 year period 2004-2014 was identified and then assigned to either the no heart failure group (NHF, N=978) or the heart failure group (HF, N=1160). Sub-groups of the NHF subjects analyzed further based on the absence (NHFA, n=383) or presence (NHFP, n=595) of observed cardiac arrhythmias. The mortality rates were reported and survival trends were compared between groups. Results: The mean age of these patients was 61.8+/-15.2 years (men 69.2%). The HF group was older, (65 vs 58) and had significantly more comorbidities. Pharmaceutical and medical resource utilization was also uniformly higher within the HF group. The 30 day (1.8%) and one year (16.6%) mortality rates among the HF patients were 3-4 times higher than in the NHF group. A coexistent major diseases score was constructed and these analyses indicated the disease score was consistently associated with a progressive mortality risk in ICD recipients overall. Conclusions: Of those receiving ICDs, the prognosis for HF patients is poorer than for those in the NHF group which most likely reflects the fact that the HF patients were generally older with more complicated medical conditions.
Tropical Deforestation Alters Leaf Wetness Duration
Amelia Min-Venditti
Georgianne Moore

Amelia Min-Venditti

and 2 more

January 14, 2020
In tropical rainforests, large-scale deforestation is considered one of the biggest threats to the environment. This threat has been shown to contribute to a loss of biodiversity, carbon storage, and hydrological services such as erosion control, streamflow regulation, and water quality. Interception losses are a much higher proportion of the water budget in areas such as moist tropical forests, where precipitation can exceed 3000 mm per year. Given interception is higher in forests with large canopy storage capacity than low stature vegetation, we aimed to identify the relative differences in leaf wetness duration in Costa Rican premontane forest and adjoining cropland. Biomass alone determines maximum interception storage, but does not determine interception loss, since storage can saturate with relatively small rain events. We aimed to determine if leaf wetness duration (LWD) is positively correlated with interception. Forest leaves stayed wet five times longer than the crop fields, 487 ± 41 minutes compared to 94 ± 37 minutes. Within crop species, papaya took twice the time to dry than taro and sweet potato (137 ± 51 in contrast to 73 ± 23 minutes). Crop heights were well correlated with dry-down rates (r2 = 0.98). These results suggest the possibility of higher runoff and alteration of rainfall recycling in the humid tropics, following tropical forest conversion to cropland.
Temporal Variability of Sediment Load in the Tonle Sap and Lower Mekong Rivers, Cambo...
Ty SOK
Chantha Oeurng

Ty SOK

and 4 more

January 14, 2020
The Mekong River, one of the world’s great rivers, is facing the disruption of its sediment balance with anthropic reductions in its sediment load and resultant impacts on nutrient fluxes, aquatic ecology and evolution of its river channel, floodplain and delta. Using long-term monitoring data from 1993-2018, we estimated the temporal variability of sediment loads in Tonle Sap and Lower Mekong Rivers in Cambodia, assessing the sediment linkage between Tonle Sap Lake and Mekong River, which are connected by a seasonally reversing flow through the Tonle Sap River. We used data from three monitoring stations established in Cambodia in 1993, from the Mekong at Kratie (upstream) downstream to the Mekong at Chroy Changvar (just upstream of the Tonle Sap confluence), and the Tonle Sap River at Prek Kdam (about 40 km upstream of the Mekong confluence). We estimated the annual sediment in the main Mekong River was 72±38 Mt/yr at Kratie and 78±22 Mt/yr at Chroy Changvar from 1993-2018. Our calculated sediment load for the Lower Mekong River is lower than reported in older studies (prior to the 2000s), which is consistent with sediment trapping by dams on Upper Mekong mainstream and major tributaries built since 1993, and consistent with other recent estimates of sediment load on the Lower Mekong. Our analysis of water discharge and sediment concentration indicates that Tonle Sap Lake provided 0.65±0.6 Mt of sediment annually to the Lower Mekong River from 1995 to 2000. However, since 2001, Tonle Sap Lake has become a sink for sediment, accumulating an average of 1.35±0.7 Mt annually. Net storage of sediment in Tonle Sap Lake reduces the annual sediment transport to the Mekong delta, further compounding the effects of sediment delivery to the Delta resulting from upstream dam construction and instream sand mining.
A Compact Printed UWB Notch Antenna with a slotted Radiating Element and Split Ring R...
SHUBHALAXMI MOHAPATRA
Satyadeep Das

SHUBHALAXMI MOHAPATRA

and 4 more

January 14, 2020
The design of a compact notch monopole antenna for application in ultra-wide band frequency domain is presented. The enhanced impedance bandwidth of the proposed antenna and a preliminary notch at 4.7 GHz are obtained by creating the square slot in the circular radiating element, an open ended slot is also created in the ground plane just below the microstrip feed-line and an open ended slit ring in the thick protruded stub erected from the upper portion of the square slot in the circular radiating element. The tuning of the notch frequency of 5.5 GHz in the WLAN band of 5-6 GHz as well as the further enhancement of notch is obtained by embedding a split ring resonator (SRR) in the left side of the microstrip feed line. The proposed UWB notch antenna provides the impedance bandwidth of 3.097GHz to 13.326 GHz (fractional bandwidth of 125%). The average measured gain of the proposed antenna is 7.1 dBi which covers the entire UWB band of operation except the notch band of WLAN. The group delay is consistent at around 0.2ns in whole of the UWB operating system except at the WLAN band where the measured group delay is around 2.8ns.
The evolutionary ecology of faking sick
Luke Larter
James Barnett

Luke Larter

and 4 more

January 14, 2020
Natural selection often produces traits that enable organisms to detect and avoid infected conspecific or environments deemed to be of high risk for parasite acquisition. We propose that such traits could foster the evolution of dishonest signals of infection. We describe herein instances where dishonest signals of infection could be favored by natural selection and the various costs and benefits likely to be associated with them. We further review the available evidence suggesting that such traits could evolve and the ecological contexts which might foster or impede their evolution. Finally, we provide a model verifying that a stable frequency of dishonest signalers of infection can be maintained in populations, at least in principle, and that the stable frequency of dishonest signalers increases with the prevalence of the infection. We conclude that dishonest signals of infection could evolve and be maintained in a variety of systems and warrant further scrutiny.
Global Biogeography of Fungal and Bacterial Biomass Carbon in Topsoil
Liyuan He
Jorge Rodrigues

Liyuan He

and 10 more

January 14, 2020
We synthesized 1323 combinations of phospholipid fatty acid-derived fungal biomass C (FBC), bacterial biomass C (BBC), and fungi:bacteria (F:B) ratio in topsoil, spanning 11 major biomes. We found that the FBC, BBC, and F:B ratio display clear biogeographic patterns along latitude and environmental gradients including mean annual temperature, mean annual precipitation, net primary productivity, root C density, soil temperature, soil moisture, and edaphic properties. At the biome level, the highest FBC and BBC densities are observed in tundra, at 3684 (95% confidence interval: 1678~8084) mg kg-1 and 428 (237~774) mg kg-1, respectively. The lowest FBC and BBC densities were found in deserts, at 16.92 (14.4~19.89) mg kg-1 and 6.83 (6.1~7.65) mg kg-1, respectively. While the F:B ratio ranges from 1.8 (1.6~2.1) in savanna to 8.6 (6.7~11.0) in tundra. Combining an empirical model of F:B ratio with the global dataset of soil microbial biomass C, we then produced global maps for FBC and BBC in 0-30 cm topsoil. Global stock of C was estimated to be 12.6 (6.6~16.4) Pg C in FBC and 4.3 (0.5~10.3) Pg C in BBC in topsoil. This work creates a benchmark for explicit use of microbial data in modelling biosphere-atmosphere feedbacks in a changing environment.
Deep learning: To better understand how human activities affect the value of ecosyste...
Chang Liu
Yi Qi

Chang Liu

and 5 more

January 14, 2020
The increase in human activities is one of the important factors affecting the value of ecosystem services. However, understanding of the driving mechanisms of human activities is limited. We established a deep learning model to approximate the ecosystem service value (ESV) of Nanjing City using 23 socioeconomic factors. A multi-view analysis was then conducted on feasible impact mechanisms using model disassembly. The results indicated that factors such as the proportion of ecological waters in the land-use structure and secondary industry output value had their own independent effects on ESV. Other intrinsically related factors, for instance, industrial water consumption and industrial electricity consumption, were likely to be composited together to affect ESV.
Reproductive character displacement and underlying drivers in a species-rich and flor...
Erin Tripp
Kyle G. Dexter

Erin Tripp

and 2 more

January 14, 2020
Reproductive character displacement is a pattern whereby sympatric lineages diverge more in reproductive character morphology than allopatric lineages. This pattern has been observed in many plant species, but comparably few have sought to disentangle underlying mechanisms. Here, in a hyperdiverse lineage of Neotropical plants (Ruellia; Acanthaceae), we present evidence of reproductive character displacement in a macroevolutionary framework (i.e., among species) and document mechanistic underpinnings. In a series of inter-specific hand pollinations in a controlled glasshouse environment, we found that crosses between species that differed more in overall flower size, particularly in style length, were significantly less likely to produce viable seeds. Further, species pairs that failed to set seed were more likely to have sympatric distributions in nature. While these findings could result from competition for pollinators or differential fusion of sympatric populations based on variable crossability, our results instead lend support for a role of reinforcement whereby selection has acted to increase reproductive barriers between sympatric species, especially given divergence in floral traits less likely to be under selection by pollinators (i.e., style length). Our results add to growing evidence that character displacement contributes to exceptional floral diversity of angiosperms.
No evidence of genetic structure in a sky island endemic: implications for population...
Krista Oswald
Shelley Edwards

Krista Oswald

and 4 more

January 14, 2020
Mountain habitats physically isolated from one another (“sky islands”) represent a unique system for studying dispersal in seemingly isolated populations. The Cape Fold Belt of southwest South Africa forms a sky island archipelago of high-altitude mountain fynbos of which the Cape Rockjumper Chaetops frenatus is an avian-endemic. Continued contraction of habitat due to increasing temperatures may be causing further isolation of C. frenatus populations beyond their dispersal capacities, resulting in currently declining populations in warmer areas of their habitat. In this study, we sequenced two mitochondrial loci and one nuclear locus of 73 C. frenatus samples from 13 localities representing 8 mountain ranges. We found (1) low overall genetic diversity, (2) no evidence for geographically-based genetic structuring, and (3) no evidence for inbreeding within localities. While this may indicate birds are effectively dispersing, it may also indicate strong selective pressure is being placed on their specific genotype. Haplotype networks suggested that C. frenatus may have experienced a bottleneck or founder effect in their recent genetic past —- a result supported by a significantly negative Tajima’s D value. As the first avian genetic study to arise from a range-restricted species of the Cape Fold Belt sky islands, our results show no evidence that C. frenatus are unable to disperse across inhospitable lowland habitat, and thus may not experience isolation due to climate change. We thus potentially found further support that selective pressure in species with highly specialized habitat niches may have a stronger effect than dispersal limitations.
Liquid biopsy in lung cancer: tertiary prevention potential
fabiana rubba
Umberto Malapelle

fabiana rubba

and 10 more

January 13, 2020
Abstract Aims In the era of personalized therapy liquid biopsy is considered an important diagnostic tool in the clinical management of cancer patients. Tissue specimen represents “gold standard” for molecular evaluation of specific gene targets alterations that lead cancer patients to benefit of a “tailed therapy” based on molecular features of the tumor. This innovative source of nucleic acids was introduced in clinical setting only for NSCLC patients to test Epidermal Grow Factor Receptor (EGFR) mutations when tissue is not available or to monitor acquired resistance mutation after a first line of treatment. The study aimed at assessing the diagnostic potential of liquid biopsy in balanced tertiary screening modeling. Methods From 2014 to 2019 molecular diagnostics activity performed on liquid biopsy specimens in the Predictive Diagnostic laboratory of AOU Federico II were reviewed. Laboratory data were collected in SPSS. Non parametric analysis were performed in order to test the differences between patients WILD TYPE or not. A multivariate logistic model was performed in order to assess the effect of mutation, age and sex, on the tumor progression. The results of the revision concern 515 total cases (almost of all plasma or peripheral blood) allowed to evaluate the liquid biopsies for women and men. The average age of the Patients is 66.3 years, and the 25 percentile is 59 years. Results The cases are 221 basal and 294 by progression after first line TKIs treatment. The cases with mutation, as expected, have an OR 4,15 compared to the basal to have a tumor progression (95% IC: 2,7 - 6,3) regardless of sex and age. The mutations detected were 131 from different types of lung carcinomas.Conclusions Working on case data, specifying the characteristics of the Patients with mutations will drive a further estimate in tertiary prevention screening designs
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