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Waste Paper Pulp Ash as Partial Replacement of cement in Cement Mortar
Melaku Zewdie
Getasew Zewdie

Melaku Zewdie

and 2 more

September 12, 2020
The application of cement in various fields of construction makes it a very important engineering material. However, it is very expensive and releases carbon dioxide gas into the atmosphere. Therefore, it is crucial to find cheap and environmentally friendly alternatives to cement. Waste paper pulp ash (WPPA) was found to be one of the most mature cement substitute materials. In this work, the physical and mechanical properties of cement mortar with WPPA as partial replacement of cement were experimentally studied to ensure that the resulting mixes has appropriate mechanical properties. Cement mixes containing various percentage replacements of WPPA (5%, 10%, 15% and 20%) were prepared, and basic properties such as compressive strength, flexural strength, shear bond strength, efflorescence and water absorption were determined and compared with the control mix (0%). The basic mechanical properties of cement mortar containing WPPA are enhanced until the percentage of WPPA reaches 10%. However, a further percentage of WPPA substitution causes the mechanical strength of the mortar to decrease. It is found that the optimal level of WPPA as a cement substitute is 5%. Although the physical properties of WPPA blended paste are improved with the increase of WPPA percentage. Our research provides a typical example of how the use of cement mortar containing WPPA can aid to the development of building materials. In addition to having better mechanical strength, cement-WPPA mixed mortar is a cost effective and environmentally friendly material.
Benralizumab Effect on Severe Nasal Polyps: A Randomized Placebo Controlled Trial
Jody Tversky
Andrew P. Lane

Jody Tversky

and 2 more

September 14, 2020
Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) can be a severe and debilitating disease associated with significant morbidity, complete anosmia, sinus pressure, and asthma exacerbations. Eosinophils play a role in the majority (85%) of patients. Benralizumab, an afucosylated monoclonal antibody directed against the IL-5 receptor has powerful apoptotic effects on eosinophils. Objective: We sought to investigate the therapeutic benefit of inhibiting the IL-5 receptor using benralizumab to treat severe nasal polyposis. Methods: Twenty-four patients (n = 24) with severe NP (grade 5 or more out of 8) with elevated eosinophils and a history of previous polypectomy were randomized in a double-blind fashion to receive 30mg benralizumab SC or placebo. Endoscopic NP score was assessed at baseline and at treatment week 20. CT scan, SNOT-22 survey, and UPSIT smell test score changes were also evaluated from baseline. Results: Compared to baseline, 8 out 12 patients receiving benralizumab had a significantly improved NP score versus 4 out of 12 placebo. 5 of 12 benralizumab treated patients had improvements in all major outcomes (polyp score, CT, SNOT-22 and smell test) versus 2 out of 12 placebo. The ratio of blood eosinophil count to allergen skin test positivity correlated with polyp reduction. Conclusion: Compared to baseline, benralizumab achieved a statistically significant reduction in polyp size by endoscopy and CT scan and was associated with both less symptoms and improved sensation of smell for most patients (10 of 12).
Is surgery necessary for adults with Isolated Interrupted Aortic Arch?: Case series w...
Yefan Jiang
Chen Wang

Yefan Jiang

and 3 more

September 14, 2020
Background and Aim: Interrupted aortic arch (IAA) is defined as a complete interruption of aortic lumen between the ascending and descending aorta. It is an uncommon and complicated congenital heart disease with high mortality in infants. It is rare for patients with isolated IAA to survive to adulthood without operation unless the extensive collateral vessels joining the descending aorta. Here we present three unique cases with isolated IAA together with a review of the literature. Methods: case presentation: We retrospectively searched the hospital patient databases for patients (>14 years) with IAA diagnosed at the Wuhan Union Hospital over the past 10 years and excluded the patients with other cardiac malformations. Three patients were identified. Two were referred to us for hypertension management and were diagnosed with IAA at our hospital. They both declined surgical treatments and underwent conservative therapy including management of their hypertension. One patient was referred to our hospital for further treatment options after the patient was diagnosed with IAA at another hospital. This patient received an extra-anatomic bypass surgery from ascending aorta to descending aorta. His high blood pressure did not resolve and was subsequently managed by anti-hypertensives medications after the surgery. Discussion and conclusions: Adult patients with isolated IAA usually have extensive collateral vessels joining the descending aorta. Surgical intervention may not be necessary for these patients if the patients have no symptoms except hypertension. Anti-hypertensives medical management with long term follow-up appears to be a reasonable treatment option for these patients.
Mycobacterium chimaera infection after cardiac surgery Catastrophic effects of delaye...
Igor Vendramin
Maddalena Peghin

Igor Vendramin

and 4 more

September 14, 2020
To the Editor: The interesting and timely paper by Cain et al.1, in press in the Journal of Cardiac Surgery , provides important details concerning the devastating consequences of Mycobacterium chimaera (MC ) infection. In their patient extreme fragility of the mediastinal tissues was observed after repair of an acute aortic dissection; during follow-up multiple reoperations were required to treat recurrent dehiscence of the aortic grafts. Despite repeat explantation of foreign materials infection persisted with mediastinitis and eventual systemic diffusion with fatal outcome.MC infection after open cardiac surgery using cardiopulmonary bypass has been recently reported as a clinical outbreak worldwide and identified as originating by contaminated water in heater-cooler units2. Current experience shows that MC causes a slow-growing and extremely difficult to treat infection with an incubation period which has been recently demonstrated to be as long as >12 years3.We have recently treated a patient, quite similar to that reported by Cain et al.1, who presented with a pseudoaneurysm of the distal suture line twelve years after repair of type A aortic dissection4. At first operation replacement of the ascending aorta and hemiarch using of a Djumbodis®dissection system (Saint Come-Chirurgie, Marseille, France) was performed. At reoperation extremely fragile tissues were noted and, after removing the metallic stent, the aortic arch was replaced with a frozen elephant trunk technique. Cultures of the excised material grewMC . In this case we hypothesized that the stent played an important role in the onset of infection for at least 2 reasons: presence of foreign material in the blood stream and injury to the aortic wall by the edges of the stent. The case described by Cain et al.1 also supports our belief that extreme fragility of the aortic tissues caused by MB was a further important factor in the occurrence of this complication.Interestingly, a delayed diagnosis occurred in both cases; this most likely played a critical role in favouring development of extra‐cardiac manifestations of the disease, in reducing the effectiveness of antibiotic therapy due to immunologic impairment and causing a negative outcome in both patients.MB infection may have different locations ranging from single-organ to systemic manifestations5. When it involves the mediastinum and particularly the major vascular structures often results in life-threatening complications despite proper antimycobacterial treatment. An early diagnosis, even with significantly extended surveillance, appears extremely difficult due to slow-growing and long incubation period of MB .Although no specific guidelines are so far available, intra-operative prevention with improvement of setting and development of heater-cooler units is mandatory and should be based on specific recommendations5.
Fatigue analysis of monopile weldments under service loading conditions using a cycli...
Romali Biswal
Abdullah Mamun

Romali Biswal

and 2 more

September 14, 2020
This paper investigates the cyclic deformation behaviour of S355 G10+M steel which is predominantly used in offshore wind applications. The thick weldments were identified as regions prone to fatigue crack initiation due to stress concentration at weld toe as well as weld residual stress fields. The monopile structure was modelled using a global-local finite element (FE) method and the weld geometry was adopted from circumferential weld joints used in offshore wind turbine monopile foundations. Realistic service loads collected using SCADA and wave buoy techniques were used in the FE model. A non-linear isotropic-kinematic hardening model was calibrated using the strain controlled cyclic deformation results obtained from base metal as well as cross-weld specimen tests. The tests revealed that the S355 G10+M base metal and weld metal undergo continuous cyclic stress relaxation. Fatigue damage over a period of 20 years of operation was predicted using the total elastic-plastic strain energy accumulated at the root of the weldments as the life limiting criterion. This study helps in quantifying the level of conservatism in the current monopile design approaches and has implications towards making wind energy more economic.
Development and Validation of Models for Durability Estimation of Exhaust Manifolds u...
Mareike Wendt
Wolfgang Rehm

Mareike Wendt

and 1 more

September 12, 2020
Air-gap insulated exhaust manifolds are mainly stressed by thermo-mechanical loads (TMF). To calculate the components with regard to their durability, a material model was created using a nonlinear kinematic model of strain hardening based on Low-Cycle-Fatique-(LCF)-tests and multi-level creep tests. On this basis, an energy-based model for life estimation was developed. The simulation of the LCF tests showed a good correlation. The model was validated on the hot gas test rig using a bended pipe. Furthermore, a model was developed to calculate welds. LCF tests with welded specimens were carried out and based on these tests, the material model of the basic material was modified for the welded areas.
Improving acetic acid and furfural resistance of Saccharomyces cerevisiae by regulati...
Bo Li
Li Wang

Bo Li

and 5 more

September 14, 2020
Acetic acid and furfural are the two prevalent inhibitors coexisting with glucose and xylose in lignocellulosic hydrolysate. The transcriptional regulations of S. cerevisiae in response to acetic acid (Aa), furfural (Fur), and the mixture of acetic acid and furfural (Aa_Fur) while fermenting with glucose and xylose were revealed. The pathways classified as carbohydrate metabolism were significantly enriched in response to Aa, while the pathways belonged to xenobiotics biodegradation and metabolism were significantly enriched in response to Fur. In addition to these pathways, some new pathways were activated in response to Aa_Fur, i.e., cofactors and vitamins metabolism, and lipid metabolism. Overexpression of Haa1p or Tye7p improved xylose consumption rate by nearly 50%, while the ethanol yield enhanced by nearly 8%. Further co-overexpression of Haa1p and Tye7 resulted in 59% increase in xylose consumption rate and 12% increase in ethanol yield, revealing the beneficial effects of Haa1p and Tye7p on improving the tolerance of yeast to mixed fermentation inhibitors.
Study of Osteogenic Potential of Electrospun PCL incorporated by Dendrimerized Superp...
Mahsa Khalili
Hamid Keshvari

Mahsa Khalili

and 5 more

September 14, 2020
Nanotechnology plays a promising role in biomedical applications, particularly tissue engineering. Recently, the application of magnetic scaffolds and pulsed electromagnetic field (PEMF) exposure has been considered in bone tissue regeneration. In this study, 3rd generation dendrimer-modified superparamagnetic iron oxide nanoparticles (G3-SPIONs) are synthesized comprehensively characterized. Magnetic polycaprolactone (PCL) nanofibers are prepared by incorporating G3-SPIONs within the electrospinning process ,and physicochemical characteristics ,as well as cytocompatibility and cell attachment are assessed. Eventually, the osteogenic differentiation ability of adipocyte-derived mesenchymal stem cells (ADMSCs) cultured on the magnetic scaffold with and without PEMF exposure was investigated by measurement of alkaline phosphatase (ALP) activity and calcium content. The expression of specific bone markers was studied using the Real-time PCR method. According to the results, G3-SPIONs with mean size and zeta potential of 17.95 ± 3.57 nm and 22.7 mV, respectively, show a high saturation magnetization (57.75 emu/g). Adding G3-SPIONs to PCL significantly decrease nanofibers size to 495±144 nm and improves cell attachment and growth. The ADMSCs cultured on the G3-SPION-PCL scaffold in the presence of osteogenic media (OM) and exposure to PEMF expressed the highest Osteocalcin and Runx2 and showed higher calcium content as well as ALP activity. It can be concluded that the synthesized G3-SPION incorporated PCL nanofibers serve as a promising magnetic scaffold for bone regeneration. Also, utilizing the magnetic scaffold in the presence of OM and PEMF provides a synergistic effect toward osteogenic differentiation of ADMSCs. Key Words: Superparamagnetic iron oxide nanoparticles, Dendrimer, Polycaprolactone, Pulsed electromagnetic field, Bone tissue engineering
A new treatment of convex functions
Mohammad sababheh
Shigeru Furuichi

Mohammad sababheh

and 2 more

September 12, 2020
Convex functions have played a major role in the field of Mathematical inequalities. In this paper, we introduce a new concept related to convexity, which proves better estimates when the function is somehow more convex than another.\\ In particular, we define what we called $g-$convexity as a generalization of $\log-$convexity. Then we prove that $g-$convex functions have better estimates in certain known inequalities like the Hermite-Hadard inequality, super additivity of convex functions, the Majorization inequality and some means inequalities.\\ Strongly related to this, we define the index of convexity as a measure of “how much the function is convex”.\\ Applications including Hilbert space operators, matrices and entropies will be presented in the end.
Phenotypic overlap between pyruvate dehydrogenase complex deficiency and FOXG1 syndro...
Yuichi Akaba
Satoru Takahashi

Yuichi Akaba

and 6 more

September 14, 2020
Pyruvate dehydrogenase complex (PDHC) deficiency is a mitochondrial disorder. We report two cases of PDHC deficiency with clinical symptoms and brain imaging findings reminiscent of FOXG1 syndrome, suggesting a phenotypic overlap of these disorders.
Avoidable lethal torsade de pointes during pacemaker generator exchange caused by bep...
Yoichi Ajiro
Toshiharu Koike

Yoichi Ajiro

and 4 more

September 14, 2020
A 92-year-old small-framed man developed torsade de pointes during pacemaker-generator exchange. His family physician prescribed bepridil 200 mg/day. High bepridil concentration of 1409 ng/mL was revealed. Electrophysiologists at pacemaker clinic should pay attention to arrhythmia management including bepridil concentration when the family physician prescribes bepridil to a pacemaker patient.
Plant heat tolerance characterizes carbon assimilation strategy
Timothy Perez
Annika Socha

Timothy Perez

and 3 more

October 01, 2020
The heat tolerance of photosystem II (PSII) may promote carbon assimilation at higher temperatures and may help explain plant responses to climate change. PSII heat tolerance could lead to 1) increases in the high temperature compensation point (Tmax); 2) increases in the thermal breadth of photosynthesis (i.e. the photosynthetic Ω parameter) to promote a thermal generalist strategy of carbon assimilation; 3) increases in the optimum rate of carbon assimilation Popt and promote faster carbon assimilation; and/or 4) increases in the optimum temperature for photosynthesis (Topt). To address these hypotheses, we tested if the Tcrit, T50 and T95 metrics of PSII heat tolerance were correlated with each carbon assimilation parameter for 21 species. Hypothesis 1 was not supported, but we observed that T50 may estimate the upper thermal limit for Tmax at the species-level, and that community mean Tcrit may be useful for approximating Tmax. The T50 and T95 heat tolerance metrics were positively correlated with Ω in support of hypothesis 2. We found no support for hypotheses 3 or 4. Our study shows that high PSII heat tolerance is unlikely to improve carbon assimilation at higher temperatures, but may characterize thermal generalists with slow resource acquisition strategies.
Shenandoah Watershed Study-Virginia Trout Stream Sensitivity Study (SWAS-VTSSS): stre...
Ami L. Riscassi
Todd Scanlon

Ami L. Riscassi

and 3 more

September 14, 2020
The Shenandoah Watershed Study (established in 1979) and the Virginia Trout Stream Sensitivity Study (established in 1987) serve to increase understanding of hydrological and biogeochemical changes in western Virginia mountain streams that occur in response to acidic deposition and other ecosystem stressors. The SWAS-VTSSS program has evolved over its 40+ year history to consist of a temporally robust and spatially stratified monitoring framework. Currently stream water is sampled bi-hourly during high-flow events at 3 sites and weekly at 4 sites within Shenandoah National Park (SHEN), and quarterly at 72 sites and on an approximately decadal frequency at ~ 450 sites within the wider western Virginia Appalachian region. Stream water is evaluated for pH, acid neutralizing capacity (ANC), base cations (calcium, magnesium, sodium and potassium ion), acid anions (sulfate, nitrate and chloride), silica and ammonium, with a subset of samples evaluated for monomeric aluminum and dissolved organic carbon. Hourly stream discharge (4 sites) and in-situ measurements of conductivity, water and air temperature (3 sites) are also measured within SHEN. Here we provide an overview and timeline of the SWAS-VTSSS stream water monitoring program, summarize the field and laboratory methods, describe the water chemistry and hydrologic data sets, and document major watershed disturbances that have occurred during the program history. Website links and instructions are provided to access the stream chemistry and time-series monitoring data in open-access federal databases. The purpose of this publication is to promote awareness of these unique, long-term data sets for wider use in catchment studies. The water chemistry and hydrologic data can be used to investigate a wide range of biogeochemical research questions and provide key inputs for models of these headwater stream ecosystems. SWAS-VTSSS is an ongoing program and quality assured data sets are uploaded to the databases annually.
Surgical treatment of 2 cases of primary cardiac malignant tumor
pengying zhao
ruisheng liu

pengying zhao

and 4 more

September 14, 2020
Cardiac tumors are a rare disease in clinical practice. Two patients with primary cardiac malignancies were admitted to our hospital from May 2020 to July 2020. The first patient‘s heart tumor is non-Hodgkin’s lymphoma, which originated in the right atrium and invaded part of the right atrium and superior vena cava. The tumor was completely removed and the right atrium and superior vena cava were reconstructed after surgery. The prognosis of the patients after chemotherapy is fair. The second patient’s tumor also originated in the right atrium, which was an epithelioid hemangioendothelioma, it was highly malignant and had a wide range of tumor invasion. The right atrium, left atrium, right ventricle, aortic root, and superior and inferior vena cava were all involved and could not be completely surgically removed, so the patient’s prognosis is poor.
SAVR and TAVR: The Role of the Heart Team Towards a Tailored Approach. Benoit de Vare...
Benoit de Varennes

Benoit de Varennes

September 14, 2020
The well-accepted role of the Heart Team in assessing patients suffering from aortic stenosis is becoming the standard approach in most centers. A tailored approach to individual patients may lead to significant changes in outcomes even though SAVR will continue to play a major rollin the treatment of patients presenting more co-morbidities and anatomical challenges.
Internal common carotid artery stenosis in concomitant with subclavian artery occlusi...
Azin alizadehasl
Leila Najmafshar

Azin alizadehasl

and 2 more

September 14, 2020
Takayasu arteritis is a chronic vasculitis that affects large vessels and causes focal or diffuse thickening of the vessel walls with consequent stenosis, occlusion, or thrombosis. Here, we describe a young lady with Takayasu, which had Internal common carotid artery stenosis and subclavian artery occlusion with focusing on the value of transthoracic echocardiography (2D) in the diagnosis of these complications of Takayasu.
Emergence of Klebsiella pneumoniae strains with reduced susceptibly against 3rd gener...
Kabiru Akinyemi
Rebecca Abegunrin

Kabiru Akinyemi

and 7 more

September 14, 2020
Different samples (i.e. stool, blood, urine, sputum, wound swabs, nasal swabs etc.) from 127 patients with suspected gram-negative infections based on on-site performed Gram-stain from four public hospitals between March and September 2015 in Lagos, Nigeria were analysed. Klebsiella (K.) pneumonia was identified in 43 (34%) patients. Resistance rates of these 43 strains according to the CLSI breakpoints were as followed: cotrimoxazole (90.7%), cefuroxime (74.4%), ofloxacin (55.8%), ceftazidime (46.5%), and cefixime (35%). Three isolates (7%) were resistant to imipenem. All isolates were susceptible to amoxicillin/clavulanic acid and nitrofurantoin. The prevalence of ESBL-producing and carbapenem resistant strains (CRKP) was 69.8% and 7.0%, respectively. Of the ESBL producing isolates, two K. pneumoniae isolates obtained from urine harbored both blaCTX-M-1 and blaSHV and a third isolate from urine harbored only blaCTX-M-1. Emerging of CRKP strains is an early warning signal for the prudent use of carbapenem antibiotics in concern to their efficacies.
MULTI-TARGET MOLECULE TO TREAT DIABETIC NEPHROPATHY IN RATS
Md Abdul Khan
Sung Hee Hwang

Md Abdul Khan

and 6 more

September 14, 2020
Background and Purpose: Diabetic nephropathy is one of the most common complications that is related to high morbidity and mortality in type 2 diabetic patients. We investigated ability of a novel dual modulator, PTUPB that concurrently acts as a soluble epoxide hydrolase inhibitor and as a cyclooxygenase-2 inhibitor against diabetic nephropathy. Experimental Approach: Sixteen-week-old type 2 diabetic and proteinuric obese ZSF1 rats were orally treated with vehicle, PTUPB, or enalapril for 8 weeks. Key Results: PTUPB alleviated diabetic nephropathy in obese ZSF1 rats by reducing albuminuria by 50%, renal tubular cast formation by 60-70%, renal fibrosis by 40-50%, glomerular injury by 55% and preserved glomerular nephrin expression. Enalapril demonstrated comparable effects and alleviated diabetic nephropathy in obese ZSF1 rats by reducing all kidney injury parameters by 30 to 50%. Diabetic renal injury in obese ZSF1 rats was accompanied by renal inflammation with 6-7-fold higher urinary MCP-1 level and renal infiltration of CD-68 positive cells. PTUPB and enalapril reduced renal inflammation but PTUPB demonstrated superior anti-inflammatory actions than enalapril. Obese ZSF1 rats were also hypertensive, hyperlipidemic, and exhibited liver injury. Interestingly, PTUPB but not enalapril decreased hyperlipidemia and liver injury in Obese ZSF1 rats. Conclusion and Implication: Overall, we demonstrate that a dual modulator PTUPB does not treat hyperglycemia, but can effectively alleviate hypertension, diabetic nephropathy, hyperlipidemia, and liver injury in type 2 diabetic rats. Therefore, we suggest that PTUPB has promising potential to be developed as a novel therapy for type 2 diabetic nephropathy and other complications.
From activated charcoal to selective plasma exchange: A retrospective analysis of mus...
Gülbahar Çalışkan
Elif Çizmeci

Gülbahar Çalışkan

and 5 more

September 14, 2020
Background/aim: This study aims to evaluate presenting symptoms, clinical and laboratory findings, and treatment modalities of adult patients presenting with mushroom poisoning treated in the intensive care unit (ICU) with special consideration of extracorporeal liver support systems. Materials and methods: Records of patients with mushroom poisoning treated in the ICU between January 2007 and December 2014 were analyzed retrospectively. Results: Sixteen adult patients were treated in the ICU for mushroom poisoning during the designated study period. Presentation to the hospital was most common during October of each year. Average time from ingestion of mushrooms to first symptoms was 17.81 hours, and to ICU admission was 2.38 days. The most common symptoms were nausea, vomiting and diarrhea. The most common laboratory finding was elevation of liver transaminases. In cases with elevated liver transaminases, penicillin G, silibinin and N-acetyl cysteine were used. Extracorporeal support systems were used in 9 cases. Two cases underwent emergency liver transplantation. Conclusion: Liver transplantation is the most definitive and effective treatment in indicated cases of mushroom poisoning. Extracorporeal support systems should be considered in the early period both as a treatment modality on their own or to save time until the definitive treatment is possible. The question of which extracorporeal detoxification technique to use is difficult to answer and controlled clinical trials which compare their efficacy are needed.
Psychometric properties of the Safety Climate Survey (SCS) in Austrian acute care: fa...
Manela Glarcher
Karin Kaiser

Manela Glarcher

and 3 more

September 12, 2020
Rationale, Aims and Objectives Hospitals are complex organizations with a high potential for medical errors that can be influenced by safety culture, a central aspect in research and practice to increase patient safety. Safety climate as a measurable element of safety culture, illustrates the perception of safety-relevant aspects of health care staff at a certain time. The Safety Climate Survey (SCS) is applied internationally to measure safety climate. However, psychometrics for the German SCS have yet not been evaluated. Aim of this study is to explore the factor structure, reliability, and potential usefulness of the German SCS in Austrian acute care. Methods Cross-sectional online-surveys of physicians, therapists and nurses/midwives from eight hospitals from one hospital operator were implemented. An exploratory factor analysis (EFA) was carried out, both, for the total sample and also split by two select professions (physicians, nurses/midwives). After deriving a factor structure for both professions, internal consistency and scale means were calculated for the subscales. Finally, mean subscale differences between physicians and nurses/midwives were tested. Results In summary, 933 respondents out of 5,160 eligible staff participated, reaching a response rate of 18.1%. A six-factor solution explaining 59.1% of total variance was identified in the total sample. Comparison by profession illustrated that the factor structures and item loading patterns differ between physicians (n=124) and nurses/midwives (n=713). To achieve an overarching solution, five items were excluded from consecutive subscale measures due to cross-loadings and contradictory factor loadings. Subscales demonstrated good to low internal consistency (α=0.794 to 0.535). Significant mean differences between subscales of professions were found relating to three factors. Conclusions The German SCS measures safety climate multi- rather than unidimensional, demonstrated limitations in factor structures and item loadings but overall satisfactory reliability of the subscales. When assessing safety climate, a multi-dimensional and profession-related approach must be explicitly considered.
Analysis of droplet splatter patterns during Coblation tonsil surgery in the Covid-19...
Grace Khong
Jaya Bhat

Grace Khong

and 3 more

September 14, 2020
Objectives: To assess droplet splatter around the surgical field and surgeon during simulated Coblation tonsil surgery to better inform on mitigation strategies and evaluate choice of personal protective equipment. Design: Observational study Setting: Operation theatre suite at a tertiary hospital Participants: Life size head model was used to simulate tonsil surgery using fluorescein-soaked strawberries to mimic tonsils Main outcome measures: The Coblation wand was activated over the strawberries for 5 minutes. This was repeated 5 times with 2 surgeons (total of 10 data sets). The presence of droplet around the surgical field and anatomical subsites on the surgeon was assessed in binary fashion: present or not present. The results were collated as frequency of droplet detection and illustrated as a heatmap; 0 = white, 1-2 = yellow, 3-4 = orange and 5 = red. Results: Fluorescein droplets were detected in all four quadrants of the surgical field. The frequency of splatter was greatest in the upper (nearest to surgeon) and lower quadrants. There were detectable splatter droplets on the surgeon; most frequently occurring on the hands followed by the forearm. Droplets were also detected on the visor, neck, and chest albeit less frequently. However, none were detected on the upper arms. Conclusion: Droplet splatter can be detected in the immediate surgical field as well as on the surgeon. Although wearing a face visor does not prevent splatter on the surgical mask or around the eyes, it should be considered when undertaking tonsil surgery as well as a properly fitted goggle.
Genomic data improve coalescent inference across a range of demographic parameters an...
Michael Hart
Vanessa Guerra

Michael Hart

and 3 more

September 12, 2020
Understanding the demographic context for population divergence and speciation in the sea often requires distinguishing the contributions of mutation, isolation, and gene flow on temporal or geographical scales where those diverse processes may not achieve equilibrium conditions. Coalescent isolation-with-migration (IM) models can meet this need for non-equilibrium modelling of genetic variation, but the quality of IM model parameter estimation depends on the breadth of genome sampling. Here, we describe three improvements in IM parameter estimates based on hundreds of loci from RNA-seq assemblies relative to previously published results based on few loci in two sea star study systems that differ in the tempo of population divergence. (1) Precision of all model parameter value estimates (with narrow posterior distributions) was vastly better in both study systems and resolved uncertainty around one key parameter in each. (2) Maximum likelihood estimates of some model parameters were broadly similar to previously published estimates, but with greater precision we obtained more realistic values for some parameters that were consistent with expectations based on the biogeography of the organisms. (3) We found non-zero but demographically trivial gene flow in one study system where we previously estimated gene flow to be zero, and modest symmetrical gene flow (2Nm<1) in a second study system where we previously estimated gene flow to be massive (2Nm~10) and asymmetrical. Improved understanding through judicious application of genome-wide sampling in replication studies as shown here may improve the information needed for biodiversity management and conservation.
A Pythagorean Fuzzy Multiset Approach for Multi-Robot System
Murat Kirisci
Mahmut Akyiğit

Murat Kirisci

and 1 more

September 14, 2020
Most of the real life problems embroil uncertainties, imprecision and vagueness. Fuzzy multisets and Pythagorean fuzzy sets, initially suggested by Yager, are significant mathematical models to handle such real world problems. By combining these two notions, a new kind of hybrid mathematical model is exists: Pythagorean fuzzy multisets. In this study, Pythagorean fuzzy multisets approach is applied to a multi-robot system to achieve better results using less effort and less time.
Transcriptomic changes induced by de-activation of lower glycolysis and its advantage...
Minhye Shin
Heeyoung Park

Minhye Shin

and 8 more

March 22, 2021
As a microbial host for cellulosic biofuel production, Saccharomyces cerevisiae needs to be engineered to express a heterologous xylose pathway. However, it has been challenging to optimize the engineered strain for efficient and rapid fermentation of xylose. Deletion of PHO13 (pho13) has been reported to be a crucial genetic perturbation for improving xylose fermentation. A confirmed mechanism of the pho13-positive effect on xylose fermentation is that the deletion of PHO13 transcriptionally activates the genes in the non-oxidative pentose phosphate pathway (PPP). In the present study, we reported that a pho13-positive effect was not observed from a couple of engineered strains, among the many others we have examined. To extend our knowledge of pho13-mediated metabolic regulation, we performed genome sequencing of pho13-negative strains. We identified a loss-of-function mutation in GCR2 responsible for the pho13-negative phenotype. Gcr2 is a transcriptional activator of the lower glycolytic pathway. Thus, the deletion of GCR2 (gcr2) led to deactivation of lower glycolysis as confirmed by RNA-seq. Also, gcr2 resulted in the up-regulation of PPP genes, which explains the improved xylose fermentation of gcr2 mutants. As pho13 and gcr2 cause similar transcriptional changes with PPP genes, there was no synergistic effect between pho13 and gcr2 for improving xylose fermentation. The present study identified GCR2 as a new knockout target to improve xylose fermentation and cellulosic biofuel production. Now published in Frontiers in Bioengineering and Biotechnology doi: 10.3389/fbioe.2021.654177  
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