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Separation, purification and characterization of a novel dextran produced by Leuconos...
Hua Zhong
Yu Yuan

Hua Zhong

and 4 more

April 19, 2022
In this study, a novel water-soluble exopolysaccharide—dextran, biosynthesized by Leuconostoc Mesenteroides CICC-21725 was separated, purified, and comprehensively characterized. The yield of purified dextran was 30.50 g/L and, the weight-average molecular weight (Mw) was 8.39 × 107 Da. The structure of the purified dextran determined by FT-IR, and 1H,13C NMR spectroscopy demonstrated that the dextran was of α dextran type, mainly containing α-(1→6) glycosidic bonds. The morphological observation by SEM and AFM elucidated that dextran was a cluster of micro-nano size irregular spherical particles with a rough surface. The purified dextran obtained has good thermal stability. The water absorption rate of the dextran product was 22.61%, and the viscosity was 10.17 mPas.
Concurrence of left atrial myxoma and breast cancer: underestimated value of echocard...
Fang Liu
LingYun Kong

Fang Liu

and 4 more

April 19, 2022
Breast cancer has posed great global burden around the world, while cardiac myxoma is the most common primary benign cardiac neoplasm. Herein we reported a case of concurrent breast cancer and cardiac myxoma, emphasizing the importance of preoperative transthoracic echocardiography.
Light Field Spatial Super-Resolution via Geometric Feature Interaction
Xin Chen
Yilei Chen

Xin Chen

and 4 more

April 19, 2022
Light field (LF) enables high-dimensional image data representation since it can capture spatial and angular information of light rays simultaneously. The low spatial resolution caused by the limited imaging ability of the capturing equipment and the trade-off between spatial and angular resolution greatly affects the quality and application of LF images. In this letter, we propose an end-to-end LF super-resolution (SR) method via geometric feature interaction. Firstly, the low-resolution LF images are stacked in the horizontal and vertical epipolar plane image (EPI) directions and form 3D VI stacks. Then, these stacks are put into a dual-branch network, and we alternately perform 3D convolution on the viewpoint images (VIs) and EPIs by reshaping features for better feature extraction and interaction. The proposed method can fully explore the texture information and geometric consistency of the LF, and super-resolve all VIs at the same time. Experimental results on both real-world and synthetic LF datasets show that the proposed method has higher performance than other state-of-the-art methods.
Long-term effects of homologous and heterologous SARS-CoV-2 vaccination on humoral an...
Luise Erpenbeck
Moritz M. Hollstein

Luise Erpenbeck

and 19 more

April 19, 2022
A document by Luise Erpenbeck. Click on the document to view its contents.
A Rare Case of Crigler-Najjar Syndrome Type II in a 14-year-old boy with Celiac Disea...
Sajjad   Ali
Naba Zaidi

Sajjad Ali

and 8 more

April 19, 2022
Here, we present a rare finding of CNS type II in a 14-year old boy with celiac disease as well as the management and outcome of CNS among the paediatrics population. Although CNS has been associated with other conditions, there have been no documented association with celiac disease.
Next-generation phenotyping contributing to the identification of a non-coding deleti...
Peter Krawitz
Fabian Brand

Peter Krawitz

and 2 more

April 19, 2022
Next-generation phenotyping (NGP) is the application of advanced methods of computer vision on medical imaging data such as portrait photos of individuals with rare disorders. NGP on portraits results in gestalt scores that can be used for the selection of appropriate genetic tests, and for the interpretation of the molecular data. Here, we report on an exceptional case of a young girl that was presented at the age of eight and fifteen and enrolled in NGP diagnostics at the latter occasion. The girl had clinical features associated with Koolen-de Vries syndrome and a suggestive facial gestalt. However, chromosomal micro array (CMA), Sanger sequencing, multiplex ligation-dependent probe analysis (MLPA), and trio exome sequencing remained inconclusive. Based on the highly indicative gestalt score for Koolen-de Vries, the decision was made to perform genome sequencing to also evaluate non-coding variants. This analysis revealed a 4.7 kb deletion at the end of intron 6 of the KANSL1 gene, which is the smallest reported structural variant to date for this phenotype. The case illustrates how NGP can be integrated into the iterative diagnostic process of test selection and interpretation of sequencing results.
Adult IgA vascularitis: A diagnosis still not clearly codified
Herveat RAMANANDAFY
léophonte samison Ramily

Herveat RAMANANDAFY

and 6 more

April 19, 2022
A 24-year-old man had vascular purpuric infiltrated, associated elbows and knees’s polyarthralgia, and abdominal pain. The proteinuria was 0.73 g/24 h. Skin histology showed a lymphocytic vasculitis lesion and perivascular infiltrates, without fibrinoid necrosis. The diagnosis IgA vasculitis was made according to the criteria of the ACR and EULAR/PRINTO/PRES.
A Metapopulation Model for Cholera with Variable Media Efficacy and Imperfect Vaccine
Phoebe Amadi
George Lawi

Phoebe Amadi

and 2 more

April 19, 2022
In this paper, a metapopulation model has been developed and analysed to describe the transmission dynamics of cholera between two communities linked by migration, in the presence of imperfect vaccine and a varying media awareness impact. Stability analysis show that the disease free equilibrium is both locally and globally asymptotically stable when the vaccine reproduction number is less than unity. The endemic equilibria have also been shown to be locally asymptotically stable when the vaccine reproduction number is greater than unity. The simulation results show that with an imperfect vaccine and efficient media awareness, cholera transmission is reduced. The transmission rates have also been shown to be nonidentical in the two communities. It is therefore advisable, that health practitioners embrace the use of both vaccination and media awareness when designing and implementing community specific cholera intervention strategies.
Study on resonance and bifurcation of fractional order nonlinear Duffing System
Xueting Bai
Jiaquan Xie

Xueting Bai

and 4 more

April 19, 2022
In this paper, resonance and bifurcation of a nonlinear damped fractional-order Duffing system are studied. The amplitude and phase of the steady-state response of system are obtained by means of average method, and then the amplitude-frequency characteristic curves of the system under different parameters are drawn based on the implicit function equation of amplitude. Grunwald-Letnikov fractional derivative is used to discretize the system numerically, and the response curve and phase trajectory of the system under different parameters are obtained, and the dynamic behavior is analyzed. The forked bifurcation behavior and saddle bifurcation behavior of the system under different parameters are investigated by numerical simulation.
Starlikness Associated with Euler Numbers
Khadija Bano
Mohsan Raza

Khadija Bano

and 1 more

April 19, 2022
Let $\psi _{E}\left( z\right) =\sec h\left( z\right) =\underset{n=0}{\overset% {\infty }{\sum }}\frac{E_{n}}{n!}z^{n},$ where the constants $E_{n}$ are Euler numbers. The class $\mathcal{S}_{E}^{\ast }$ denote the class of normalized analytic functions $f$ satisfying $zf^{\prime }(z)/f(z)\prec \psi _{E}\left( z\right) $. For this class, we obtain structural formula, inclusion results, and some sharp radii problems such as radius of convexity, radius for the class of Janowski starlike functions and radius for some other subclasses of starlike functions. We also find sharp coefficient results and sharp Hankel determinants for functions in the class $\mathcal{S}_{E}^{\ast }.$
An autocorrelation function-based method used for image denoising with accuracy and e...
Shengnan Zuo
Chenguang Cai

Shengnan Zuo

and 4 more

April 19, 2022
Noise is always inevitably appeared in images, which directly affects the performance of machine vision applications. Currently, the commonly used denoising methods can be divided into three strategies: the filtering-based, model-based, and deep learning-based methods. However, they are always difficult to get the considerable accuracy and efficiency simultaneously. In this study, a novel denoising method based on autocorrelation function is investigated, which improve the image quality by utilizing the independence of useful periodic information and noise. Simulations and experiments compared with the current denoising methods confirm that the investigated method has a good comprehensive effect on noise reduction and efficiency improvement.
Establishing UK Research Priorities In Smell and Taste Disorders: A James Lind Allian...
Carl Philpott
Andreas Espehana

Carl Philpott

and 9 more

April 19, 2022
Background: A James Lind Alliance Priority Setting Partnership (JLAPSP) was established by Fifth Sense together with UEA to identify the top 10 research questions in the field of smell and taste disorders in the United Kingdom. Methods: After steering group was established, an electronic survey was disseminated to all stakeholders (patients, healthcare professionals, family, carers, researchers) to determine the list of questions. After removing out-of-scope responses, the remainder were consolidated to create summary questions. A literature search was conducted to remove already answered questions. A second survey was used to determine the top questions that formed the subject of final debate at a workshop attended by clinicians and patients to determine the top 10 priorities. Results: The 665 respondents to the initial survey provided 1698 research questions. Thirteen were out-of-scope and removed; remaining 1685 were then consolidated to form 147 summary questions. Following literature search and discussion with the steering group, 37 questions remained for the second survey, which 235 people responded. The top ten priorities agreed in the workshop covered themes of improved understanding of pathophysiologlogy, improving health services, and managing long-term effects of smell/taste disorders. The most important research question agreed was “How can we further our understanding of the mechanism of disease in the nerve pathways that affect smell and taste disorders, including where parosmia and phantosmia exist.” Conclusions: We report the top 10 research priorities in smell and taste disorders. These priorities will now empower researchers to secure research funding and provide the basis of the Fifth Sense research hub.
Instrument for the evaluation of higher surgical training experience in the operating...
Kin Lun Lau
Rachel Scurrah

Kin Lun Lau

and 2 more

April 19, 2022
Introduction Surgical trainees have to achieve a set level of operative competence under the timeframe set by the intercollegiate surgical curriculum. The operating theatre as the primary learning environment needs to be conductive to achieve successful training. In this project, we developed and validated a 27-item questionnaire which aims to evaluate the training experience of higher surgical trainees in the operating theatre. Methods Initial questionnaire was developed by reviewing existing instruments. The questionnaire was then modified in a focus group to explore themes perceived to be important to training. The modified questionnaire was sent out to obtain the content validity index (CVI) of each item. Lastly, the final version was disseminated and Cronbach’s alpha was derived to measure the internal consistency of the questionnaire. Results The Initial version of 33 questions was modified in focus group into a 29-item 4-point Likert scale questionnaire covering three areas. 14 responses were received from higher surgical trainee and consultants to determine the CVI. 27 out of 29 items reached the threshold index of 0.87. Finally, the 27-item questionnaire achieved a Cronbach’s alpha of 0.88 from 17 responses. Discussion The Cronbach’s coefficient of 0.89 in the resultant questionnaire is comparable to other existing medical education evaluation tools, which indicates a high internal consistency. Our validated questionnaire can be utilized to identify areas that needs to be improved as perceived by higher surgical trainees and to improve their training experience in theatre.
Improving the management of cervical chyle leak following neck dissection: A case ser...
Ali Al-lami
Eamon Shamil

Ali Al-lami

and 6 more

April 19, 2022
Key points instead of abstract as per author guidelines: • Chyle leaks (CLs) following neck dissection for metastatic head and neck malignancy are infrequent but represent a serious complication, with an incidence of 1-2.5%. • CL is associated with significant morbidity including metabolic imbalance, immunosuppression, dehydration, poor wound healing and prolonged length of hospital stay. • A protocolised approach to the management of CL post neck dissections is highlighted for expedient patient management. • Thoracic duct (TD) ligation using video-assisted thoracoscopic surgery (VATS) is an effective method of treating moderate (500-1000ml/24 hours) to high-volume CL (>1000ml/24 hours) not responding to medical therapy. • VATS TD ligation is a safe procedure to treat CL. It has a low morbidity compared to other surgical techniques (neck re-exploration or open thoracotomy).
A new GNSS spoofing signal power control algorithm for receiver in acquisition phase...
Yangjun Gao
Guangyun Li

Yangjun Gao

and 1 more

April 19, 2022
A new global navigation satellite system (GNSS) spoofing signal power control algorithm under the power constraints of receiver in acquisition phase and the subsequent control is proposed in this letter. In spoofing algorithm, constraints of successful spoofing are analyzed, objective function is constructed, the power allocation optimization algorithm based on sequential quadratic programming (SQP) is proposed, and the best scheme of spoofing is given. Experimental platform is designed to prove that compared with conventional spoofing signal high power control algorithm, the new spoofing signal power control algorithm shortens Doppler frequency fluctuation time by 72.2% and reduces the range by 75.9%. The carrier-to-noise ratio of received signal is less than the threshold of receiver, and the range of three-dimensional coordinates of ECEF is significantly reduced during spoofing signal taking over receiver, This shows that the new design of spoofing signal power control algorithm can make spoofing behavior more covert, and it will make it more difficult for target receiver to detect spoofing behavior. The designed algorithm can take over receiver stealthily with the help of jamming and then pull the positioning results, which has good feasibility and effectiveness.
Features of metaheuristic algorithm for integration with ANFIS model
Shirmohammad Tavangari

Shirmohammad Tavangari

and 1 more

April 18, 2022
In recent years, many applications based on the Neural Network, Neuro-Fuzzy, and optimization algorithms have been more common for solving regression and classification problems. In the Adaptive neuro-fuzzy inference system(ANFIS), many researchers used the adaption of metaheuristic algorithms with ANFIS to propose the best estimation model. However, many researchers only focused on the experiment without the demonstration mathematical or indicating which characteristic of optimization algorithm, during the run, affect and settable in coordination with ANFIS. The paper provides an adaption of metaheuristic algorithms with ANFIS which has been performed by considering accuracy parameters in layer 1 and layer 4 for the estimation problem. It is integrated six well-known metaheuristic algorithms and extracting the characteristic of them. In the experiment, the metaheuristic algorithms based on the evolutionary computation have been demonstrated more stable than swarm intelligence methods in tuning parameters of ANFIS.
Imaging findings of small cell neuroendocrine carcinoma of the ureter
Gui-Wu Chen
Yuhuan Xie

Gui-Wu Chen

and 4 more

April 18, 2022
Small cell neuroendocrine carcinoma (SCNEC) of the ureter is a rare malignant tumor originating from the metaplasia of urothelial cells. This report presents a case of ureteral SCNEC that was preliminarily disclosed by transabdominal ultrasonography; thereafter, transrectal ultrasonography and magnetic resonance urography were performed to characterize the focus.
A primary rectal B-cell lymphoma revealing Crohn's disease
Mohamed Ali Jouini
Asma Labidi

Mohamed Ali Jouini

and 4 more

April 18, 2022
Primary rectal lymphoma is the rarest disorder of all primary gastrointestinal lymphomas. The association between Crohn's disease and primary rectal lymphoma is also very rare and there are a few case reports in the literature describing the association between these two diseases.
Management of a pregnant woman with a large cervical polyp in the first trimester: A...
Yoshiaki Saitsu

Yoshiaki Saitsu

April 18, 2022
Polypectomy during pregnancy is known to be a risk for spontaneous late miscarriage or preterm delivery. We managed a 34-year-old pregnant woman with a large cervical polyp without polypectomy, and we administered probiotics including Clostridium butyricum and 17-alpha-hydroxyprogesterone caproate. As a result, she delivered a healthy baby at 38 weeks.
13-year-old massive facial desmoplastic fibroblastoma in a 50-year-old patient
arpita singh
Snehashish Ghosh

arpita singh

and 5 more

April 18, 2022
Desmoplastic fibroblastoma is a benign soft tissue tumor of fibroblastic and myofibroblastic origin. The present case report depicts an unusually large desmoplastic fibroblastoma, in a 50-year-old female. The lesion presented on the left side of the face, mimicking a soft tissue malignancy. Keywords: benign, desmoplastic, fibroblastoma, female.
Fabrication of nano-scale superhydrophobic surfaces on silicon substrates using direc...
Yuan Li
tengfei Zheng

Yuan Li

and 2 more

April 18, 2022
The scale of the structure is a key parameter of the superhydrophobic surfaces. In this work, DLIP are used to fabricate nanostructures on silicon substrates that have been processed with microstructures to make multiscale superhydrophobic surfaces. By adjusting several key process parameters, the depth, spacing, and other geometric shapes of the prepared nanostructures are controlled, and finally the manufacture of multi-scale structures with fixed specifications is realized. In this work, we use DLIP as a fabrication method for nanostructures in multi-scale structures. This method has the advantages of repeatable large-area processing, fast processing speed, high processing accuracy, and controllable structure.
A 44-year-Old Male with Esophageal Ulcer
Delvise Fogwe
Shah Aditya

Delvise Fogwe

and 2 more

April 18, 2022
A 44-year-Old Male with Esophageal UlcerQuestion: A 44-year-old male was admitted for acute gastrointestinal bleed, intermittent esophageal dysphagia, and odynophagia. His past medical history was significant for dermatomyositis, for which he was on mycophenolate but had previously received prednisone and methotrexate. The treatment for his dermatomyositis had been complicated by pancytopenia with Hemoglobin 6.8 (13.2 - 16.6 g/dL), platelet 73 (135 - 317 x10(9)/L), and white blood cells 1.9(3.4 - 9.6 x10(9)/L). He underwent esophagogastroduodenoscopy (EGD), which showed a deep esophageal ulcer on the background of diffuse white plaques in the middle third of the esophagus and a non-bleeding large cratered clean-based gastric antral ulcer (Figure 1, A&B). Barium swallow showed a sac-like structure consistent with the ulcer without contrast leakage to suggest a fistula (Figure 1, C). What is the most likely diagnosis?Answer: This is a classic presentation of Cytomegalovirus (CMV) esophageal ulcer. The biopsy of the ulcer revealed positive CMV immunostaining, with negative immunostaining for Herpes simplex virus and fungus. His quantitative CMV DNA was 20400 IU/mL (Reference range Undetected), and his HIV test was negative. CMV predominantly causes opportunistic infection in immunosuppressed patients. It mainly causes gastrointestinal symptoms, with about 12.9% of patients presenting with esophageal disease. Unlike other infectious esophageal ulcers, CMV tends to cause one or more giant (>1cm) ulcers that may be flat, ovoid, or diamond-shaped.
Primary synovial chondromatosis in children: a case report and literature review
Bettaieb Hiba
Hanene Ferjani

Bettaieb Hiba

and 1 more

April 18, 2022
Primary synovial chondromatosis is an uncommon and benign metaplastic condition that usually affects large joints. Though shoulder involvement is scarce, and there are only a few cases in the pediatric population.
Synchronization of fractional-order chaotic systems using optimal control problem
Sohrab Karimi
Seyed Ali Rakhshan

Sohrab Karimi

and 2 more

April 18, 2022
A focus of this article is the study of synchronization between nonlinear chaotic systems with fractional order. Here synchronization is achieved by employing optimal control based on active control. As a result of the application of the proposed technique, the synchronization for the pair of chaotic systems amongst the chaos of Lorenz’s system with fractional order and Rössler system with fractional order is successfully investigated. The graphic representation of numerical simulation results shows that controller laws can effectively and reliably synchronize fractional-order chaotic systems.
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