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Predicting the Actual Location of Faults in Underground Optical Networks using Linear...
Owusu Nyarko-Boateng
Adebayo Adekoya

Owusu Nyarko-Boateng

and 2 more

May 07, 2020
Optical cables are enormous transmission media which carries high-speed data across transatlantic, intercontinental, international boundaries and cities. The optical cable is essential in data communication. The cable has become an indispensable component in optical communications infrastructure; hence, conscious efforts are always adopted to prevent or minimize faults in the optical network infrastructure. Typically, tracing fault in the underground optical network has been difficult even though optical time-domain reflectometer (OTDR) has been used to measure the distance of faults in the underground fiber cable. The methodologies deployed in the reviewed literature indicate a vast gap between the fault distance measured by the OTDR and the actual distance of fault. This paper observed the difficulties involved in tracing the actual spot of fault in the underground optical networks. The difficulty of tracing these underground faults mostly result in an undue delay and loss of revenue. This research presents a machine learning (ML) approach to predict the actual location of a fiber cable fault in an underground optical transmission link. Linear regression technique was used to predict the actual location of a fault. Single-layer perceptron and sigmoid activation function were applied in the predictive model to obtain good accuracy value.
World Protected Areas Management, Wildlife Migration and COVID-19 Outbreak: Developin...
Saba Kalantary
Ali Jahani

Saba Kalantary

and 2 more

May 07, 2020
Emerging or re-emerging zoonotic diseases are the main issue in global health and affect the well-being of nations. COVVID-19 originated from a wet market where wild animals are sold and rapidly outbreak across worldwide. Analysis outlined bats are key host, so COVID-19 is a zoonotic disease and crossed from animals into humans. Wildlife migration among world protected areas and disease transmission has caused an increased risk of emerging or re-emerging of zoonotic diseases such as COVID-19. Transboundary animal diseases (TDAs) make the health approach more crucial as these diseases cause many problems. Hence, the prevention and control of zoonotic diseases are critical. In this paper, we addressed world protect areas management, wildlife migration, and preventive and control measures aspects on zoonotic diseases such as COVID-19 that have already been globally recommended. South American and African countries due to higher coverage of protected areas in human development regions; and Asian and South American countries due to lack of protected area management assessment are more prone to transmit COVID-19 by wildlife migrations. World Health Organization should pay attention to the determined countries for more practical health care plans in protected area communities and settlement especially in facing with wildlife species.
Preparation and Purification of Porcine Circovirus Type 2 Chimeric Virus-Like Particl...
Jie Zhang
Tushuai Li

Jie Zhang

and 10 more

May 07, 2020
Porcine epidemic diarrhea virus (PEDV) causes severe watery diarrhea with dehydration and high mortality in pigs, bringing huge economic losses to the swine industry worldwide. The current prevention of PEDV is mainly concentrated on inactivated vaccines. In this study, two novel B cell epitopes S1D5 (residues 744-759) and S1D6 (residues 756-771) of PEDV were displayed on capsid (Cap) protein of porcine circovirus type 2 (PCV2) in Escherichia coli (E. coli) expression system. The recombinant protein Cap-S1D can self-assemble into chimeric virus-like particles (VLPs), which were similar in size and morphology to native PCV2 particles. In addition, an effective affinity purification system for the purification of chimeric VLPs, referred to Gram-positive Enhancer Matrix-protein anchor domain-variable domain of heavy chain of heavy-chain antibody 8 (GEM-PA-VHH8), was screened and identified. The PA-VHH8 fusion protein can specifically bind to GEM particles by covalent bond adsorption, which contributes to display Cap-S1D chimeric VLPs on the surface of GEM particles. Cap-S1D chimeric VLPs were successfully purified with the developed purification system and the purification efficiency was close to 90%. What’s more, the purified chimeric VLPs homemade vaccine induced a stronger humoral and cellular immune responses compared to the unpurified recombinant protein in pigs. Thus, the GEM-PA-VHH system provided an effective and safe technology for the preparation and purification of chimeric VLPs to prevent PEDV and PCV2 infection.
The Correlation between Left Atrial Longitudinal Strain and Atrial Fibrillation in Di...
Al-Shimaa Sabry
Hany Ebaid

Al-Shimaa Sabry

and 3 more

May 07, 2020
Objectives: To assess the correlation between left atrial (LA) longitudinal strain and occurrence of atrial fibrillation (AF) in patients with dilated cardiomyopathy (DCM). Methods: 100 patients with DCM were evaluated. Conventional and speckle tracking echocardiography were done to evaluate LA diameters, volumes and longitudinal strain. Results: Left atrial dimensions and volumes were significantly greater in AF group. LA longitudinal strain and LA emptying fraction were significantly lower in AF group. LA longitudinal strain and LA minimal volume are independent predictors for AF presence. ROC curve showed that LA longitudinal strain cut-off value <11.1% can predict the presence of AF in DCM patients with 96% sensitivity and 95.3% specificity (AUC 0.982, 95% CI 0.959–1.0, P < 0.001) Conclusion: Left atrial longitudinal strain was significantly reduced in AF in the setting of DCM. LA longitudinal strain and LAVmin are independent predictors for AF occurrence in this group of patients with LA strain values <11.1% can be used to predict AF in DCM.
A Case of a Supercharged Compound Flap for Necrotizing Soft Tissue Infection
Kiichi Furuse
Motoi Kato

Kiichi Furuse

and 5 more

May 07, 2020
In this report, we present a case of the Superficial circumflex iliac perforator-intercostal artery perforator (SCIP-ICAP) compound flap after extensive debridement of the upper extremity with necrotizing soft tissue infection (NSTI). There has been no previous report of the SCIP-ICAP compound flap applied for the upper extremity with NSTI.
GANGRENOUS CHOLECYSTITIS: A SURGICAL COMPLICATION OF TYPHOID FEVER IN A CHILD.
Vivian Akello
Denis Bitamazire

Vivian Akello

and 3 more

May 07, 2020
The occurrence of gangrenous cholecystitis as a complication of typhoid fever is rare. This is a case study of a 7 year old that presented with fever and abdominal pain and later developed abdominal distension. She was later diagnosed with a gangrenous cholecystitis and gall bladder empyema.
Synchronous Primary Brain Tumors in the Pediatric Age Group. Report of Two Cases and...
Omar Chamdine
Marwah  Abdulkader

Omar Chamdine

and 5 more

May 07, 2020
Synchronous brain tumors are rare in children. We present 2 unique cases of synchronous brain tumors and we elaborate on their presentation, diagnosis, approach to management, and outcome. The first case describes a unique and previously unreported combination of a supratentorial anaplastic ependymoma and a cerebellar low-grade glioma.
Protein A Immunoadsorption combination with Immunosuppressive Therapy Improve Neurops...
Feng  Wen
Xiaoling  Wu

Feng Wen

and 15 more

May 07, 2020
Neuropsychiatric systemic lupus erythematosus (NPSLE) is usually associated with a worse prognosis. However, there are few effective treatments for NPSLE. We described protein A immunoadsorption treatment for a patient with NPSLE. The patient’s brain lesions was improved rapidly after two sessions of protein A immunoadsorption combination with immunosuppressive agent treatment.
Does straw retention sustain soil carbon stocks in Brazilian sugarcane fields?
Sarah Tenelli
Ricardo Bordonal

Sarah Tenelli

and 4 more

May 07, 2020
Sugarcane straw is a crop residue known as the main input of carbon (C) to the soil, but its removal represents a valuable asset for bioenergy purposes, which may adversely affect soil organic C (SOC) stocks. Most studies related to this issue is limited to site-specific conditions and comprehensive studies in a wide range of soils and climate regions are scarce. This study was designed to evaluate temporal SOC stocks changes induced by sugarcane cultivation and straw management in the southern-central of Brazil. Ten field experiments were arranged in a randomized block design with four replications, including four straw removal rates: total (TR), high (HR), low (LR) and no removal (NR). Soil samples were collected to a 30-cm depth at the beginning of the trial establishment and after four consecutive years. The dataset suggested that 19% and 25% of the C added via straw were accumulated into the soil of the sandy and clayey areas, respectively. This study showed strong SOC depletion in sandy soils at rates of 1.4, 1.5, 1.9 and 2.3 Mg ha-1 year-1 under NR, LR, HR and TR, respectively. In contrast, clayey soils exhibited SOC accumulation over time, even removing all the straw from the soil surface. Based on SOC changes, these findings provide a robust scientific basis to support policy and management decisions for straw-derived bioenergy, showing that the removal of sugarcane straw may be potentially advantageous in clayey soils but should be avoided in sandy soils of tropical regions in Brazil.
Unraveling molecular mechanism underlying biomaterial and stem cells interaction duri...
Erfan Sharifi
Niusha Khazaei

Erfan Sharifi

and 5 more

May 07, 2020
Stem cell (SC) differentiation towards somatic cells has proven to be an effective technique in the understanding and progression of regenerative medicine. Despite improvements, concerns regarding the efficiency of differentiation and the differences between SC products and their in vivo counterparts must be addressed. Biomaterials that mimic endogenous growth conditions represent one recent method used to improve the quality and efficiency of SC differentiation. Here, we aim to use bioinformatics approaches to accomplish two aims: 1) determine the effect of different biomaterials on SC growth and differentiation, and 2) understand the effect of cell of origin on the differentiation potential of multipotent SCs. First, we demonstrate that the dimensionality (2D versus 3D) and the degradability of biomaterials affects the way that the cells are able to grow and differentiate at the transcriptional level. Additionally, the particular cell of origin is an important factor in determining the response of SCs to same biomaterial transcriptionally. Our data demonstrates the ability of bioinformatics to understand novel molecular mechanisms and context by which SCs are most efficiently able to differentiate. These results and strategies may suggest proper combinations of biomaterials and SCs to achieve high differentiation efficiency and functionality of desired cell types.
Enantiomers of quinolones and their activeness for different targets to cure malaria:...
Mohd Suhail
Imranl Ali

Mohd Suhail

and 1 more

May 07, 2020
In the case of chiral antimalarial drugs (chloroquine, primaquine, and quinacrine), it becomes very difficult to understand the mechanism of these chiral drugs because these drugs are prescribed in the racemic form in which one enantiomeric form cures malaria, while another does not, or cause side effects. Here, we have developed a computational method for the enantiomeric interaction of chiral antimalarial drugs with different targets for the first time. Using Marvin sketch and Discovery Studio Visualizer, all the pdb files of all the enantiomers were obtained, while the pdb files of targets (β-hematin, DHFR-TS, DHFR-TS quadruple mutant) were obtained from the protein data bank. All the enantiomers were docked with different targets to find the binding affinity using AutoDock Tools (ADT) 4.2). The enantiomeric forms causing side effects as well as the most biologically active enantiomeric forms and their target were resolved. Docking study showed that the most biologically active enantiomeric forms in the presented chiral antimalarial drugs are ‘R‘ of chloroquine; ‘S‘ of primaquine and ‘R‘ of quinacrine‘. The presented study helps not only in determining the target of these chiral drugs but also in discovering the most biologically active enantiomeric form of these drugs, which may be responsible for the better treatment of malaria. Besides, the presented study also opens the doors for the better treatment of other disease for which the chiral drugs taken in the present study are prescribed such as chloroquine and hydroxychloroquine for coronavirus (2019-nCoV). Keywords: Chiral quinolones, targets, computational study and (2019-nCoV).
Traumatic Incudostapedial Disarticulation: Anatomical Reconstruction Using Ionomeric...

May 07, 2020
A document by Mohamed Ghonim . Click on the document to view its contents.
Cardioprotective effect of silicone built restraint device (ASD), for left ventricle...
Waqas Nawaz
Muhammad Naveed

Waqas Nawaz

and 9 more

May 07, 2020
Purpose: This study was to assess the feasibility and cardio-protective effects of biocompatible silicon built restraint device (ASD) in rat’s heart failure (HF) model. Background: Ventricle restraint therapy (VRT) is a well-established and promising approach for management of advanced-stage dilated HF. Previous VRT devices offer a subjective level of restraint to the dilated heart muscles. However, the impact of the restraint nature, mesh tubular design and biocompatibility of VRT devices is not well investigated. Method: The performance and compliance of ASD were determined in vitro by adopting a pneumatic drive and ball burst test. SD rats were grouped into four (n=24); control, HF, ASD+HF and CSD+HF groups, respectively. HF was induced by left anterior descending artery ligation in all groups except the control group. ASD and CSD devices were implanted in the heart of ASD+HF and CSD+HF groups respectively. Results: The functional and expansion ability of ASD was observed to be safer and suitable to attenuate ventricular remodeling. ASD treated rats showed normal heart rhythm which was validated by a smooth -ST and asymmetrical T-wave. Hemodynamic parameters, and systolic and diastolic functions improved in the ASD+HF group and reduction in ventricular wall stress indicated reverse remodeling. Furthermore BNP values were reduced in ASD+HF group which confirmed ASD feasibility and reverse remodeling at a molecular level. ASD+HF group also showed no fibrosis thus proposing that ASD has its significant curative effects on the heart muscles. Conclusion: ASD was found to be a promising restraint therapy than the previously standard restraint therapies.
Machine Learning-based Prediction of Enzyme Substrate Scope: Application to Bacterial...
Zhongyu Mou
Jason Eakes

Zhongyu Mou

and 7 more

May 07, 2020
Predicting the range of substrates accepted by an enzyme from its amino acid sequence is challenging. Although sequence- and structure-based annotation approaches are often accurate for predicting broad categories of substrate specificity, they generally cannot predict which specific molecules will be accepted as substrates for a given enzyme, particularly within a class of closely related molecules. Combining targeted experimental activity data with structural modeling, ligand docking, and physicochemical properties of proteins and ligands with various machine learning models provides complementary information that can lead to accurate predictions of substrate scope for related enzymes. Here we describe such an approach that can predict the substrate scope of bacterial nitrilases, which catalyze the hydrolysis of nitrile compounds to the corresponding carboxylic acids and ammonia. Each of the four machine learning models (linear regression, random forest, gradient-boosted decision trees, and support vector machines) performed similarly (average ROC = 0.9, average accuracy = ~82%) for predicting substrate scope for this dataset. The approach is intended to be highly modular with respect to physicochemical property calculations and software used for docking and modeling.
Successful Treatment of Hepatosplenic T Cell Lymphoma in an Adolescent with Turner Sy...
Colette Lauhan
Deborah Schiff

Colette Lauhan

and 2 more

May 07, 2020
Abbreviations key:
Clinical evaluation of Li Brush endometrial samplers for diagnosing endometrial lesio...
Lu Han
Sijia Ma

Lu Han

and 12 more

May 07, 2020
Objective: To investigate the feasibility and diagnostic accuracy of endometrial biopsy using Li Brush sampler in IUD users. Design: Clinical research Setting: A public teaching hospital in China. Population: IUD users with irregular uterine bleeding and IUD non-users who arranged for dilatation and curettage at the First Affiliated Hospital of Xi’an Jiaotong University, China from January 2018 to January 2020. Methods: This study was conducted in two parts. Part Ⅰ was to assess the impact of Li Brush on the position of IUDs. Transvaginal ultrasound was used to locate IUDs before and after sampling. Part Ⅱ was to explore the diagnostic accuracy of Li Brush in detecting endometrial lesions. Both IUD users and non-users were recruited, and the sampling satisfaction and accuracy of Li Brush were evaluated. Main outcome Measures: The positions of IUDs before and after sampling, cytopathological and histopathological diagnosis, sampling satisfaction rate. Results: Seventeen cases in part Ⅰ confirmed no significant difference in the position of IUDs before and after sampling (p=0.20). 112 IUD users and 139 IUD non-users were recruited in part Ⅱ. The Li Brush achieved 94.64% and 92.09% sampling satisfaction in the IUD group and control group, respectively, and the overall diagnostic accuracy was 88.04% and 93.33% in the two groups. Conclusions: Li Brush used for endometrial biopsy did not affect the position of IUDs and had high sampling satisfaction and accuracy for endometrial diagnoses.
Pediatric Cancer Research: Surviving COVID-19
Jeffery Auletta
Peter Adamson

Jeffery Auletta

and 11 more

May 07, 2020
A diverse panel of pediatric cancer advocates and experts, whose collective experience spans the continuum of international academic medicine, industry, federal research, and cancer advocacy, recently discussed challenges for pediatric cancer research in the context of Coronavirus Disease 2019 (COVID-19). Specifically, this special report addresses the following focus areas: (1) the critical role that translational research has played in transforming pediatric cancer outcomes; (2) the current and potential future impact of COVID-19 on pediatric cancer research; (3) target areas of COVID-19 research that may have application in immunity, oncogenesis and therapeutic discovery; and (4) future considerations and directions in maintaining pediatric cancer research during and after COVID-19.
Resident Perception of Standardization and Credentialing for High Risk Bedside Proced...
Olugbenga Okusanya
Alexandrea Bartow

Olugbenga Okusanya

and 9 more

May 07, 2020
Objectives: Though guidelines are set by the American Board of Thoracic Surgery for the operative cases that cardiothoracic surgery residents must perform to be board-eligible, no such recommendations exist to assess competency for the wide range of high-risk bedside procedures. Our department created and implemented a multi-disciplinary developed course designed to standardize common high-risk bedside procedures and credential our residents. The aim of this study was to survey the attitudes of residents to and query the efficacy of such a course. Methods: The course was designed with the goal of standardizing endotracheal intubation, arterial line insertion (radial and femoral), central venous line insertion, pigtail tube thoracostomy and nasogastric tube placement. The course consisted of an online module followed by a 4-hour hands on simulation session. Knowledge based pre and post evaluations were administered as well as Likert based survey regarding multiple aspects of the residents’ perceptions of the course and the procedures. Results: Twenty-three (7 traditional and 16 integrated) cardiothoracic surgical residents participated in the course. Residents reported that 48% of the time, bedside procedures were historically taught by other trainees rather than faculty. All residents endorsed increased standardization of all procedures after the course. Likewise, residents showed increased confidence in all procedures except for pigtail and thoracentesis as well as nasogastric tube placement. 43.5% of the participants demonstrated improvement in the pre and post-test knowledge-based evaluations. ConclusionCardiothoracic residents have favorable attitudes towards standardization and credentialing for high risk bedside procedures and utilizing such courses may help standardize procedural techniques.
Surgical management of a giant atrial septal aneurysm
Motoyuki Kumagai
Junichiro Nishizawa

Motoyuki Kumagai

and 4 more

May 07, 2020
A 63-year-old woman presented with chest discomfort. Coronary angiography revealed vasospastic angina. Cardiac multi detector computed tomography and cardiac magnetic resonance imaging showed a 30 × 30-mm atrial septal aneurysm (ASA) protruding into the right atrium and thrombus attached to the left side of the ASA pouch. We surgically resected the ASA because the patient was at risk for systemic thrombosis. The resection site was closed with pericardial patch through a median sternotomy under a cardiopulmonary bypass. The postoperative course was uneventful, and the patient was discharged on postoperative day 26.
On the Search of Small Cu-Ru Atomically Precise Superatoms. Cu10Ru Cluster as a Stabl...
Peter Rodriguez-Kessler
Adan Rodríguez-Domínguez

Peter Rodriguez-Kessler

and 5 more

May 07, 2020
Atomically precise metallic clusters behaving as superatoms, are relevant building blocks towards new materials under the bottom-up approach. Here we discussed the plausible formation of the Cu10Ru cluster as a superatomic specie accounted its 1S2 1P6 1D10 shell order, with the aim of identification of particular clusters with enhanced stability. By stochastic structure search on Cu10Ru clusters, we found six low-lying cluster isomers with ΔE values from 0.0 to 4.7 kcal∙mol above the ground state denoting an endohedral motif with the Ru dopant inside the Cu10 cage, as the favored structures. By using molecular dynamics simulations we found a clear trend of encapsulation of the Ru atom at low temperatures, quantified by the Cu-Ru bonding distances during the annealing procedure. The 17-ve counterpart, Cu9Ru shows a large electron affinity, owing to the trend to achieve a electronic shell closing as a new superhalogen species. These results are useful for further rationalization and design of novel superatoms expanding the libraries of endohedral clusters.
Ischemic Mitral Regurgitation
Hashem Aliter

Hashem Aliter

May 07, 2020
Ischemic mitral regurgitation (IMR) is one of the most challenging complications of acute myocardial infarction (AMI) and chronic coronary artery disease (CAD). The presence of IMR, irrespective of severity significantly have a negative impact on the short and long-term outcomes of patients with AMI and CAD. Nearly 25% of patients with AMI without congestive heart failure (CHF) develop IMR and this number approaches 50% when CHF is present.
Lost ground: female academics face an uphill battle in post-pandemic world
Tricia A. Stadnyk
Kerry Black

Tricia Stadnyk

and 1 more

May 07, 2020
A document by Tricia A. Stadnyk. Click on the document to view its contents.
Large-scale monitoring of freshwater bivalves: an eDNA point of view on species distr...
Vincent Prié
Manuel Lopes-Lima

Vincent Prié

and 14 more

May 07, 2020
The analysis of environmental DNA (eDNA) allows efficient surveys of freshwater species and is being increasingly used. However, most studies generally have a limited sampling plan. Because different methods are used by different authors, all the data produced with eDNA cannot be easily pooled together for a global overview. Nevertheless, one of the promising perspectives is the standardization of the methods and protocols, for long-term monitoring, early detection of invasive species, and rare species detection. We here present the biggest dataset using eDNA metabarcoding with standardized methods for freshwater bivalves. Sampling was performed mainly in France, with over 350 localities spread over all major basins. Metabarcoding was performed using two new sets of primers, one for the Unionida and one for the Venerida. The species distributions inferred from eDNA sampling are then compared with those currently known. Results give an insight into the valuable data that eDNA analysis can provide if used at a large scale. Some species were found outside of their known range, especially invasive species but also species of conservation interest. Others were found in a surprisingly low number of localities, although currently considered widespread and of no conservation interest. This can be explained by the databases currently used to establish conservation status, which are often biased by including ancient data, shell-only data, and potentially misidentified species. The present study shows that our eDNA metabarcoding approach will be an essential tool to unveil the true species distributions, to better evaluate their status and improve conservation policymaking.
Impact of Evaporation on Field Capacity during Water Drainage Redistribution in a Soi...
Ali Aldrees

Ali Aldrees

May 07, 2020
To this day, field capacity (FC) is rarely defined in the context of soil properties, and the use of non-physical simplistic models is the common way to normalize water content at FC. In this study, the problem of water drainage redistribution in a soil water column with and without the presence of Evaporation (EV) was extensively studied. Analytical solutions for Richard’s equation were established for the case of water drainage redistribution through a deeply wetted soil column with and without EV at Field Capacity (FC) conditions while water retention and depth evolution curves were plotted first, using different EV values of 2 mm/day, 5 mm/day and 8 mm/day and second, for different drainage redistribution durations of 1 day, 4 days and 6 days where EV was set to zero for the case with no EV or to a fixed value of 5 mm/day for the case with EV. The results suggest that EV plays a significant role in soil water drainage suggesting that, in the presence of EV, the FC drying front reaches much higher depths in the soil water profile than if EV is turned off. It was also concluded that FC reaches deeper depths faster the stronger EV is acting AT the surface of A soil water column.
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