bluuebunny/crossref_metadata_2025 huggingface dataset:
HFO‐1234yf as a CF3‐Building Block: Synthesis and Chemistry of CF3‐Ynones
Authors: Murray Ben J. , Marsh Thomas G. F. , Yufit Dmitri S. , Fox Mark A. , Harsanyi Antal , Boulton Lee T. , Sandford Graham
Published: August 2020

Reaction of low cost, readily available 4th generation refrigerant gas 2,3,3,3‐tetrafluoropropene (HFO‐1234yf) with lithium diisopropylamide (LDA) leads to formation of lithium 3,3,3‐trifluoropropynide, addition of which to a range of aldehydes formed CF3‐alkynyl alcohol derivatives on multigram scale, which were oxidised using Dess–Martin periodinane (DMP) to give substituted CF3‐ynones with minimal purification required. Michael‐type additions of alcohol and amine nucleophiles to CF3‐ynones are rapid and selective, affording a range of CF3‐enone ethers and enaminones in excellent yields with high stereoselectivity for the Z‐isomer. By analogous reactions with difunctional nucleophiles, a wide range of CF3‐substituted pharmaceutically relevant heterocyclic structures can be accessed, exemplified in the simple synthesis of the anti‐arthritis drug celecoxib from HFO‐1234yf in just three steps.
Internet of things‐fog computing‐based framework for smart disaster management
Authors: Aljumah Abdullah , Kaur Avneet , Bhatia Munish , Ahamed Ahanger Tariq
Published: August 2020

Smart building incorporates the ubiquitous sensing ability of Internet of things (IoT) technology with the industrial infrastructure for automating decision‐making. Inspired by this, a novel technique of stochastic game net (SGN) has been proposed to minimize the tangible and intangible infrastructural losses due to disasters. Specifically, IoT technology is used for disaster management and control in a smart building based on SGN. In the proposed technique, every IoT sensor act as an individual player with prefixed action sets and strategies. Complete SGN of the IoT network in the smart building is formalized by collaborating SGN of an individual sensor. The model deployed in IoT building with different sensors detects disasters beforehand and generates early warning alerts to management units based on game‐theoretic decision‐making. Experimental evaluation on four challenging datasets, namely, disaster/accident sources, gas sensor drift, red cross smoke alarm, and oil spills show the effectiveness of a proposed framework in the smart building. The results are compared with several state‐of‐the‐art decision‐making techniques to measure the overall effectiveness of the proposed system. Based on simulations performed on NetLogo 5.3.1, enhanced results of performance parameters including temporal delay, statistical efficiency, reliability, and stability were registered. Moreover, mathematical analysis has been carried out to determine the overall performance of the presented technique.
Insulation failure of lightweight composite sandwich panels exposed to flame
Authors: Negahban Ehsan , Bagheri Ali , Al‐Dujaili Ali , Sanjayan Jay
Published: August 2020

A critical consideration for the serviceability of composite sandwich panels is their thermal behaviour during fire incidents. This research aims to observe the thermal performance and investigate the insulation failure of the lightweight concrete sandwich panels (LCSPs) in non‐load bearing wall systems. Six standard one‐sided coupling fire tests on LCSPs in accordance with Australian standard AS 1530.4 were conducted via an electrical furnace; measured by thermocouples and a thermal camera, to assess the insulation capacity and their behaviour during fire events. The results indicated that the sandwich panels have insulation capacity for 75 to 110 minutes depending on the thickness and density. The bowing of the panels due to the expansion of the exposed steel shield and the consequent de‐bonding and cracking of concrete was one of the primary reasons of insulation failure. Additionally, this bowing led to the opening of the joints between the panels, which could allow the heat flows towards the unexposed surface. Moreover, the propagation of accelerated drying shrinkage cracks in the restrained concrete core was another reason for the failure. Lastly, the results suggested the benefits of increasing the thickness and density on thermal performance and insulation failure of the composite sandwich panels.
Manufacture of fresh cheese using east African Calotropis procera leaves extract crude enzyme as milk coagulant
Authors: Abebe Bethelhem , Emire Shimelis
Published: August 2020

The present work was aimed to develop fresh cheese using the crude extract from calotropis procera leaves and thereby performed evaluating milk‐clotting activity and acute toxicity of crude extract. The extraction of coagulant was performed at 30, 45, and 60℃ using 2, 6, and 10 g of dried calotropis procera leaves, respectively. The highest yield of crude enzyme extract was acquired with 2 g and 30℃, and results were varied significantly (p < .05). The highest cheese yield and fastest clotting time were 17.89 kg cheese/100kg milk and 14:50 min acquired with 10 g C. procera powder at 60℃ extraction temperature, respectively. E. coli, total bacterial count, yeast, and mold microbial load detection were observed below the limit established by codex alimentarius. This study recommends that use of C. procera crude enzyme leaves extract can be used as alternate milk coagulant for production of fresh cheeses. Soft cheeses manufactured with calotropin enzyme as milk coagulant revealed no adverse effects of toxicity tested on albino rates to the highest dose.
Numerical investigation for improved heat transfer characteristics in micro‐fin tubes
Authors: Dhamudia Kashinath , Mishra Pradeep Kumar
Published: August 2020

Generally, internal micro‐fin tubes are used for increasing the life and performance of electronic devices. The micro‐fins enhance the heat transfer rate by increasing the surface area with an increase of the pressure drop. In this study, heat transfer and pressure drop are analyzed by varying Reynolds number with the increase in the number of fins in tubes. Heat transfer and pressure drop, together with turbulence kinetic energy of micro‐fin tubes (helical and straight) and a smooth tube, have been evaluated for different Reynolds numbers (60 000, 40 000, 20 000, and 2000) at a constant temperature of 350 K, which clearly establishes laminar to turbulent flow. It is observed that the helical micro‐fin tube has a better result compared with the straight micro‐fin tube and smooth tube at Reynolds numbers 60 000, 40 000, and 20 000 at velocity 2, 1, and 0.5 m/s, respectively. This study is an attempt to establish a comparison of different micro‐fin geometries with varying Reynolds numbers, concluding that a high Reynolds number is suitable for the same.
Influence of undulating wall heat and mass flux on MHD natural convection boundary layer flow from a vertical wall
Authors: Bala Nandita R. , Bala Shujit K. , Saha Litan K. , Hossain Md. Anwar
Published: August 2020

Current study expounds an unsteady magnetohydrodynamic natural convective flow along a vertical wall in presence of variable transverse magnetic field. Small amplitude undulation in wall heat flux and wall mass flux are imposed at the vertical wall to generate the boundary layer flow. The flow governing equations are divided into sets of steady and unsteady equations and then transformed into the similarity and nonsimilarity equations, respectively, by introducing stream function formulations. The sets of nonsimilarity equations are solved numerically by using three different techniques, namely, perturbation solution technique, asymptotic solution technique and implicit finite difference technique applied, respectively, for lower, higher, and all frequencies (ξ). Results are illustrated in connection with the amplitude and phase angles of shear stress, wall temperature, and concentration against the frequency (ξ) for wide ranges of physically significant parameters. Likening of the results obtained by above mentioned numerical methods are presented in every figure and table. Results reveal that the amplitude of undulating shear stress and wall temperature dwindle and the amplitude of wall concentration increases due to increment in Prandtl number (Pr). Besides, on incrementing Schmidt number (Sc) the amplitude of undulating shear stress and wall concentration dwindle and the amplitude of wall temperature increases. Results also reveal that on incrementing magnetic parameter (M) the amplitude of transient shear stress dwindles while the amplitude of transient wall temperature and concentration increase.
Cross flow on transient double‐diffusive natural convection in inclined porous trapezoidal enclosures
Authors: Reddy E. Suresh , Panda Satyananda , Nayak Manoj Kumar , Makinde Oluwole Daniel
Published: August 2020

This paper investigates the cross‐diffusion effects subject to exponential variable boundary conditions on transient double‐diffusive natural convection flow in an enclosure. The flow domain is a two‐dimensional inclined trapezoidal cavity filled with a porous medium. The top wall is assumed to be insulated and permeable, while the enclosure's bottom wall is subject to exponential varying temperature and concentration. The prescribed temperature and concentration are different at the vertical walls. Conservation equations are used as the governing equations. The finite element Galerkin weighted residual method, in association with the Newton‐Raphson scheme is employed to solve the system of coupled nondimensional equations. The numerical tests are confirmed with existing literature and are found to be in excellent agreement. The simulations results for stream functions, isotherms, and isoconcentrations are discussed for the various flow parameters. A sensitivity analysis using the response surface method suggests that the average Nusselt and Sherwood numbers are more sensitive to the cross‐diffusion effects. It is further observed that the cross‐diffusion terms stabilize the sensitivity to the angle of inclination.
Аtherosclerosis‐like changes in the rabbit aortic wall induced by immunization with native high‐density lipoproteins
Authors: Fomina Kseniya , Beduleva Liubov , Menshikov Igor , Zerjawi Abdulkadhim , Terentiev Alexey , Sidorov Alexandr , Khramova Tatyana , Abisheva Nadezhda , Gorbushina Anna
Published: August 2020

Introduction

A high level of total cholesterol or low‐density lipoprotein (LDL) cholesterol is considered the main cause of atherosclerosis and cardiovascular disease. For this reason, experimental atherosclerosis is induced by creating high blood cholesterol in animals. However, the hypothesis that atherosclerotic processes are mostly caused by immune (autoimmune) mechanisms has recently been gaining traction. At the same time, no experimental model has been developed that clearly demonstrates the autoimmune mechanism by which atherosclerosis develops and reproduces the full picture of atherosclerosis solely by means of an immune response, without resorting to additional interventions such as a high‐cholesterol diet or the use of genetic models of hyperlipidemia. Previously, we were able to induce atherosclerosis‐like lesions in the aorta and the development of pericardial fat in rats by immunizing them with human native lipoproteins. The purpose of this study was to test whether atherosclerosis can be induced in normocholesterolaemic rabbits by immunizing them with human native high‐density lipoproteins (hnHDL).

Methods

Rabbits were immunized with hnHDL. Aortic wall structure, plasma cholesterol level, and antibodies against HDL were studied.

Results

Immunization with hnHDL was found to cause atherosclerosis‐like lesions in the rabbit aorta such as adipocytic and chondrocytic metaplasia, proteoglycan deposits, leukocytic infiltration. Atherosclerosis‐like lesions developed in the aorta of hnHDL‐immunized rabbits against a background of normal blood LDL‐cholesterol level. Therefore, a high plasma cholesterol level is not the sole cause of atherosclerosis. The immune response against HDL is an independent cause of atherogenesis.

Conclusions

A rabbit model of atherosclerosis caused by immunization with hnHDL can be widely used to examine the mechanisms occurring during atherogenesis.
Impact of the coronavirus pandemic crisis on the financial system in the eurozone
Authors: Ito Takayasu
Published: August 2020

The stress in the financial system in five eurozone countries (Germany, France, Italy, Portugal, and Spain) was not connected before the COVID‐19 pandemic crisis. Credit default swap premiums were priced independently, not incorporating the sovereign risk of the eurozone as a whole. However, during the period of pandemic crisis, the stress was connected in five countries. The financial market was cautious about the increased fiscal deficit caused by massive spending in the pandemic crisis, fearing that the deficit might cause increased risk in the financial system of the eurozone as a whole. The symptoms of financial crisis sprouted after the pandemic crisis started. We need to monitor whether countermeasures taken by European Central Bank (ECB) and European Union (EU) contribute to the stability of financial system in the eurozone.
A comprehensive analysis of membrane fouling in microfiltration of complex linear macromolecules based on theoretical modeling and FESEM images
Authors: Heidari Setareh , Etemadi Habib , Yegani Reza
Published: August 2020

BACKGROUND

Membrane technology is an attractive alternative to conventional water/wastewater treatment technologies as it is sustainable and can be used as an independent process as well as being a part of integrated systems with other treatment technologies. Notwithstanding the abundant benefits that membrane‐based systems offer, their commercial application is overshadowed by the ubiquitous fouling. However, accurate prediction and identification of membrane fouling mechanisms can help to open new doors in recognition of appropriate arrangements for developing more effective membrane synthesis methods and fundamental strategies to achieve better performance, especially in large‐scale production.

RESULTS

In this study, three fouling models, namely resistance‐in‐series (RIS), Hermia's and combined cake filtration–pore blockage models, were applied to precisely analyze fouling behavior in dead‐end microfiltration (MF) of collagen solution, as model foulant, using pure high‐density polyethylene and modified high‐density polyethylene membranes. The RIS model was shown to be not representative of the real fouling mechanism in MF membrane units. Similarly, none of the classical models were able to accurately predict fouling in the entire MF process. However, the combined cake–intermediate blockage model provided excellent fits for the membranes.

CONCLUSIONS

Obtained results also demonstrated that physical cleaning was not enough for organic fouling elimination in MF processes. Finally, computational results were validated with experimental observations of collagen rejection and field emission scanning electron microscopy analyses as well. © 2020 Society of Chemical Industry
Identification of novel thiourea‐stilbene‐triazine conjugates as persuasive lymphoid tyrosine phosphatase inhibitors
Authors: Batool Iram , Jabeen Farukh , Vellore Nadeem Ahmed , Shabir Ghulam , Saeed Aamer
Published: August 2020

A library of novel thiourea‐based symmetrical stilbene‐triazines (5a‐i) was synthesized in an effort to develop new protein tyrosine phosphatase LYP inhibitors. The versatile nature of 2,4,6‐trichloro‐1,3,5‐triazine allows considerable scope for derivatization and hence exploration of structure activity relationships. A convenient and versatile three‐step synthetic approach involved the successive replacement of the two chloro groups of 2,4,6‐trichloro‐1,3,5‐triazine by a variety of substituents for structural modification. The newly synthesized derivatives were subjected to tyrosine phosphatase LYP inhibition studies. The results for the in vitro bioassays were promising with the identification of compound 5k and 5l having a 4‐methyl and 4‐methoxy substituent on phenyl ring, as the lead and selective candidate for LYP inhibition with an IC50 value of 2.1 ± 0.05 μM and 28 ± 3.3 μM, respectively. Moreover, docking studies were carried out to determine the possible interaction sites of thiourea‐based stilbene‐triazine compounds with Lymphoid Tyrosine Phosphatase. Results of docking computations further ascertained the inhibitory potential of compound 5k and 5l. The results indicated that the compound 5k may serve as a structural model for the design of most potent LYP inhibitors.
Chemo‐ and diastereoselective synthesis of new oxa[3.3.3]propellane via a domino cascade four‐component reaction based on diketene
Authors: Rezvanian Atieh , Salimi Mehri , Zadsirjan Vahideh , Mahmoodi Fahame , Heravi Majid M.
Published: August 2020

A highly convergent, eco‐friendly and straightforward synthesis of new O‐fused heterocycles, functionalized indeno[1,2‐b]furan derivatives was successfully accomplished through a one‐pot four‐component cascade reaction involving, ninhydrin, malononitrile, diketene and various primary amines in the presence of a catalytic quantity of triethylamine in ethanol at ambient temperature, in one pot fashion. This new efficient cascade reaction generates two rings by the simultaneous construction of C‐N (one), C‐O (two) and C‐C (two) multiple bonds, presumably through a sequence of Knoevenagel reaction/Michael addition/intramolecular O‐cyclization and imine‐enamine/keto‐enol tautomerization. The merits of this protocol are highlighted as utilization of inexpensive commercially accessible starting materials, operational simplicity, atom economy, clean reaction profile, simple work‐up procedure being conducted at ambient temperature in relatively short reaction times, preventing chromatographic purification, giving excellent yields, and tolerance to a wide variety of functional groups.
Mass filter with phase modulation of radio frequency voltage
Authors: Wu Fangling , Wang Baichun , Yan Yinghua , Konenkov Nikolai V. , Ding Chuan‐Fan
Published: August 2020

In this work, the parametric quadrupole resonance caused by the phase modulation of waveform potential is studied. Based on analytical and numerical description of the ion motion in the quadrupole mass filter with the phase modulation, a stability island is found with good ion optical properties such as high ion transmission efficiency (16%), high mass resolution (peak width measured at 10% of peak height, R0.1 = 6000), the required separation time (100–150 radio frequency [RF] cycles), and good peak shape of trapezoid form. Furthermore, the analysis of the frequency spectrum of the applied potential and the quadrupole mass filter (QMF) acceptance are also presented; a resonance frequency is found from this spectrum. Finally, a suitable stability X‐islands with relative modulation frequency,
, is established and studied in detail. Here, β is the imaginary part of the characteristic exponent of stable solutions to the Mathieu equation.
Epidemiology of COVID‐19: A systematic review and meta‐analysis of clinical characteristics, risk factors, and outcomes
Authors: Li Jie , Huang Daniel Q. , Zou Biyao , Yang Hongli , Hui Wan Zi , Rui Fajuan , Yee Natasha Tang Sook , Liu Chuanli , Nerurkar Sanjna Nilesh , Kai Justin Chua Ying , Teng Margaret Li Peng , Li Xiaohe , Zeng Hua , Borghi John A. , Henry Linda , Cheung Ramsey , Nguyen Mindie H.
Published: August 2020

Coronavirus disease 2019 (COVID‐19) has become a pandemic, but its reported characteristics and outcomes vary greatly amongst studies. We determined pooled estimates for clinical characteristics and outcomes in COVID‐19 patients including subgroups by disease severity (based on World Health Organization Interim Guidance Report or Infectious Disease Society of America/American Thoracic Society criteria) and by country/region. We searched Pubmed, Embase, Scopus, Cochrane, Chinese Medical Journal, and preprint databases from 1 January 2020 to 6 April 2020. Studies of laboratory‐confirmed COVID‐19 patients with relevant data were included. Two reviewers independently performed study selection and data extraction. From 6007 articles, 212 studies from 11 countries/regions involving 281 461 individuals were analyzed. Overall, mean age was 46.7 years, 51.8% were male, 22.9% had severe disease, and mortality was 5.6%. Underlying immunosuppression, diabetes, and malignancy were most strongly associated with severe COVID‐19 (coefficient =  53.9, 23.4, 23.4, respectively, all P < .0007), while older age, male gender, diabetes, and hypertension were also associated with higher mortality (coefficient = 0.05 per year, 5.1, 8.2, 6.99, respectively; P = .006‐.0002). Gastrointestinal (nausea, vomiting, abdominal pain) and respiratory symptoms (shortness of breath, chest pain) were associated with severe COVID‐19, while pneumonia and end‐organ failure were associated with mortality. COVID‐19 is associated with a severe disease course in about 23% and mortality in about 6% of infected persons. Individuals with comorbidities and clinical features associated with severity should be monitored closely, and preventive efforts should especially target those with diabetes, malignancy, and immunosuppression.
Late onset infectious complications and safety of tocilizumab in the management of COVID‐19
Authors: Pettit Natasha N. , Nguyen Cynthia T. , Mutlu Gökhan M. , Wu David , Kimmig Lucas , Pitrak David , Pursell Kenneth
Published: August 2020

Background

Tocilizumab (TCZ) has been used in the management of COVID‐19‐related cytokine release syndrome (CRS). Concerns exist regarding the risk of infections and drug‐related toxicities. We sought to evaluate the incidence of these TCZ complications among COVID‐19 patients.

Methods

All adult inpatients with COVID‐19 between 1 March and 25 April 2020 that received TCZ were included. We compared the rate of late‐onset infections (>48 hours following admission) to a control group matched according to intensive care unit admission and mechanical ventilation requirement. Post‐TCZ toxicities evaluated included: elevated liver function tests (LFTs), GI perforation, diverticulitis, neutropenia, hypertension, allergic reactions, and infusion‐related reactions.

Results

Seventy‐four patients were included in each group. Seventeen infections in the TCZ group (23%) and 6 (8%) infections in the control group occurred >48 hours after admission (P = .013). Most infections were bacterial with pneumonia being the most common manifestation. Among patients receiving TCZ, LFT elevations were observed in 51%, neutropenia in 1.4%, and hypertension in 8%. The mortality rate among those that received TCZ was greater than the control (39% versus 23%, P = .03).

Conclusion

Late onset infections were significantly more common among those receiving TCZ. Combining infections and TCZ‐related toxicities, 61% of patients had a possible post‐TCZ complication. While awaiting clinical trial results to establish the efficacy of TCZ for COVID‐19 related CRS, the potential for infections and TCZ related toxicities should be carefully weighed when considering use.
The Comparison of Segmental Multifrequency Bioelectrical Impedance Analysis and Dual‐Energy X‐ray Absorptiometry for Estimating Fat Free Mass and Percentage Body Fat in an Ambulatory Population
Authors: Hurt Ryan T. , Ebbert Jon O. , Croghan Ivana , Nanda Sanjeev , Schroeder Darrell R. , Teigen Levi M. , Velapati Saketh R. , Mundi Manpreet S.
Published: August 2020

Background

Despite malnutrition being associated with increased mortality and morbidity, there continues to be great difficulty in defining criteria and implementing widespread screening. Tools used to diagnose decreased fat‐free mass (FFM [sarcopenia]) should be easy to use, relatively inexpensive, and safe. Bioelectrical impedance analysis (BIA) has the potential to meet these criteria, but reliability across body mass index (BMI) classes is a concern.

Methods

A total of 176 healthy ambulatory participants (aged 18–65 years) were recruited equally (n = 44) in 4 BMI categories: (1) 18.5–24.9, (2) 25.0–29.9, (3) 30–34.9, and (4) ≥35.0. Participants were fasting overnight and had S‐MFBIA (InBody 770) measurements the next morning, with DXA being performed subsequently within 30 minutes.

Results

The measurement (mean ± SD) for FFM with DXA was 52.8 ± 11.0, and BIA was 53.6 ± 11.0. Delta (S‐MFBIA vs DXA) was 0.8 ± 2.2 (5% limits of agreement −3.5 to +5.2), and concordance correlation coefficient (CCC) was 0.98 (95% CI, 0.97–0.98). The measurements (mean ± SD) for PBF with DXA was 37.5 ± 10.6% and S‐MFBIA was 36.6 ± 11.3%. Delta (S‐MFBIA vs DXA) was −0.9 ± 2.6 (5% limits of agreement 6.0 to +4.2), and CCC was 0.97 (95% CI, 0.96–0.98). The CCC according to the 4 BMI groups for FFM and PBF was between 0.96–0.98 and 0.90–0.94, respectively.

Conclusions

FFM and PBF measured by S‐MFBIA had good agreement with DXA across all BMI categories measured in the current study of ambulatory participants.
A generalized‐weights solution to sample overlap in meta‐analysis
Authors: Bom Pedro R. D. , Rachinger Heiko
Published: August 2020

Meta‐studies are often conducted on empirical findings obtained from overlapping samples. Sample overlap is common in research fields that strongly rely on aggregated observational data (eg, economics and finance), where the same set of data may be used in several studies. More generally, sample overlap tends to occur whenever multiple estimates are sampled from the same study. We show analytically how failing to account for sample overlap causes high rates of false positives, especially for large meta‐sample sizes. We propose a generalized‐weights (GW) meta‐estimator, which solves the sample overlap problem by explicitly modeling the variance‐covariance matrix that describes the structure of dependence among estimates. We show how this matrix can be constructed from information that is usually available from basic sample descriptions in the primary studies (ie, sample sizes and number of overlapping observations). The GW meta‐estimator amounts to weighting each empirical outcome according to its share of independent sampling information. We use Monte Carlo simulations to (a) demonstrate how the GW meta‐estimator brings the rate of false positives to its nominal level, and (b) quantify the efficiency gains of the GW meta‐estimator relative to standard meta‐estimators. The GW meta‐estimator is fairly straightforward to implement and can solve any case of sample overlap, within or between studies.

Highlights

Meta‐analyses are often conducted on empirical outcomes based on samples containing common observations.

Sample overlap induces a correlation structure among empirical outcomes that harms the statistical properties of meta‐analysis methods.

We derive the analytic conditions under which sample overlap causes conventional meta‐estimators to exhibit high rates of false positives.

We propose a generalized‐weights (GW) solution to sample overlap, which involves approximating the variance‐covariance matrix that describes the correlation structure between outcomes; we show how to construct this matrix from information typically reported in the primary studies.

We conduct Monte Carlo simulations to quantify the efficiency gains of the proposed GW estimator and show how it brings the rate of false positives near its nominal level.

Although we focus on meta‐analyses of regression coefficients, our approach can, in principle, be modified and extended to effect sizes more commonly used in other research fields, such as Cohen's d or odds ratios.
Winter Survival of Female Ring‐Necked Ducks in the Southern Atlantic Flyway
Authors: Mezebish Tori D. , Olsen Glenn H. , Goodman Michele , Rohwer Frank C. , McConnell Mark D.
Published: August 2020

North American waterfowl harvest regulations are largely guided by the status of breeding populations. Nonetheless, understanding the demographics of wintering waterfowl populations can elucidate the effects of hunting pressure on population dynamics. The ring‐necked duck (Aythya collaris) breeds and winters in all North American administrative flyways and is one of the most abundant and most harvested diving ducks in the Atlantic Flyway. But few studies have investigated the winter ecology of ring‐necked ducks. We used a known‐fate analysis to estimate period survival probability using data from 87 female ring‐necked ducks marked with satellite transmitters in 2 regions of the southern Atlantic Flyway during winters of 2017–2018 and 2018–2019. Winter (128‐day) survival probability was higher for individuals in the Red Hills region of southern Georgia and northern Florida (0.875, 95% CI = 0.691–0.952) than individuals in central South Carolina (0.288, 95% CI = 0.082–0.514). We attribute the regional disparity in winter survival probabilities to differences in hunting pressure, which are reflected in the number of harvests we observed in each region. Our findings warrant further investigation into regional variation in winter survival of southern Atlantic Flyway ring‐necked ducks, and, specifically, the relationship between variable harvest pressure and winter survival and its influence on ring‐necked duck population dynamics and adaptive harvest management decisions. © 2020 The Wildlife Society.
Factors impacting international‐indexed publishing among Vietnamese educational researchers
Authors: Trinh Thao‐Phuong‐Thi , Tran Trung , Le Hien‐Thu‐Thi , Nguyen Tien‐Trung , Pham Hiep‐Hung
Published: August 2020

Despite several initiatives and policies that boost international‐indexed publishing, the outputs of social sciences in general and educational science of Vietnam in international academic databases such as Clarivate Web of Science (WoS) or Scopus are still modest. This study examined the factors affecting international‐indexed publishing among Vietnamese educational researchers. A framework for determining the influential factors was developed comprising three dimensions (policies, capacities, and networking) with 15 sub‐factors, and the Analytic Hierarchy Process (AHP) model was employed to estimate the relative importance of these factors on international publishing. A survey of Vietnamese educational researchers at higher education and research institutes was undertaken, of which 80 returned validated answers, which after analysis were reduced to 49. The study revealed that the most important factors were collaboration with domestic and international peers and receiving support from research assistants or supervisors. A closer investigation revealed differences between senior and junior researchers regarding issues such as the accessibility of scientific documents, research data, and time for research.

Key points

There are greater STEM than HSS outputs from Vietnam, although the growth of social science output is growing at a faster rate.

Both senior and junior Vietnamese educational researchers agree that local and international networking is a major factor in successful publication within internationally indexed journals.

Junior educational researchers identify available time for research as a major limiting factor in international publication where it is not identified as such by senior researchers.

Capacity‐related factors for successful publication are perceived as less limiting than policy or networking factors among Vietnamese researchers.
China–United States trade war: Does devaluation favors China? An application NARDL
Authors: Wahab Salman , Safi Adnan , Wahab Zeeshan , Amin Maaz , Zhang Xibao
Published: August 2020

The current study aims to investigate the effect of devaluation on a bilateral trade balance between China and the United States. The study uses monthly data for the period 20‐11‐2018, which is seasonally adjusted through the Seasonal Trend Decomposition using Loess (STL) method. The dependent variable used in this study is exports to import ratio, and the independent variable is the exchange rate. The study uses both linear and nonlinear ARDL methodology to trace the long run and short run effect and to trace the asymmetry between exports to imports ratio and exchange rate. Moreover, the long‐run relationship is established through Bound testing approach. The findings favor the devaluation for China trade balance both in the short run and long run. Moreover, the results do not support the existence of J‐curve and indicate that rather than devaluation it is the competitiveness of Chinese goods and services that provide an edge in bilateral trade between China and United States.
Clinical characterization and hematopoietic stem cell transplant outcomes for congenital sideroblastic anemia caused by a novel pathogenic variant in SLC25A38
Authors: Uminski Kelsey , Houston Donald S. , Hartley Jessica N. , Liu Jing , Cuvelier Geoffrey D.E. , Israels Sara J.
Published: August 2020

Background

Congenital sideroblastic anemia (CSA) constitutes an uncommon category of inherited anemia often associated with pathologic iron accumulation. Pathogenic variants in several genes have been identified as causative for CSA. Autosomal recessive pathogenic variants in the mitochondrial glycine transporter SLC25A38 have been implicated in a subset of patients with CSA.

Procedure

We describe seven individuals of Canadian Cree descent with a known or inferred homozygous novel founder missense variant in SLC25A38 (c.560G>A, p.Arg187Gln).

Results

All individuals presented as young children (median age 6 months) with severe microcytic, hypochromic anemia associated with pretransfusion iron overload, requiring red cell transfusion support and iron chelation. Six individuals received pyridoxine supplementation; two demonstrating transient partial responses. Three individuals underwent allogeneic hematopoietic stem cell transplantation (HSCT). One individual with significant iron loading died in the posttransplant period due to complications of sepsis. The other two individuals remain transfusion‐free following HSCT.

Conclusions

Despite a common genetic etiology, phenotypic variability was noted in this cohort. A transient response to pyridoxine was noted in two individuals but should not be considered a long‐term therapeutic strategy. HSCT was curative when performed before significant iron loading occurred. Early identification of CSA and timely HSCT can result in excellent long‐term outcomes.
Conjugated‐carbon nanostructures: Emergences
Authors: Klein Douglas J. , Ortiz Yenni P. , Bytautas Laimutis
Published: August 2020

General emergent features of conjugated‐carbon nanostructures are sought. Here, “general” indicates applicability over a broad class of such structures, including graphene and buckytubes, possibly with boundaries or other sorts of defects or decorations, or rather general substructures of graphene or of buckytubes. In addition, “emergent” means that different characteristics and properties are novel and are evidenced from different models, for example, from resonance theory and Hückel theory, preferably with evidence that the features persist upon elaboration. One robust emergent feature is “Dirac cones” in the band structure of graphene and some related materials. Another interesting feature is novel “blended” boundary orbitals that are delocalized longitudinally along the boundary direction while being variably localized in the transverse direction. Furthermore, defects at the ends of polymer chains may be localized or delocalized depending on local features—although the ideas apply more widely to different conjugated‐carbon structures including molecules. Explicit formulas are derived to elucidate the asymptotic behavior of unpaired electron density at the ends of selected benzenoid polymers and its relation to the associated HOMO‐LUMO gap. Our approach offers a general framework to understand ab initio results, which may, at first sight, appear to be unconventional or counterintuitive to some common ideas of bonding patterns in conjugated carbon nanostructures.
Theoretical exploration on the vibrational and mechanical properties of M3C2/M3C2T2 MXenes
Authors: Luo Kan , Zha Xian‐Hu , Zhou Yuhong , Huang Qing , Zhou Shenghu , Du Shiyu
Published: August 2020

MXenes have attracted intensive attention in chemistry and material science for their special structures and properties. In order to understand the basic physical properties of the M3C2/M3C2T2 (MSc, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W; TF, O, OH) MXenes, first‐principles calculations are carried out to investigate the structural, vibrational, and mechanical properties in this work. Both the metal atoms and surface groups can significantly influence the configurations or mechanical behaviors of the MXenes. The dehydrogenation tendency is calculated to evaluate the possible forms of the M3C2(OH)2 toward M3C2O2. The work functions of MXenes functionalized by different groups are compared, and the lower work functions for the OH functionalized ones, which can be as low as 1.358 eV for the Sc3C2(OH)2, suggest potential good performance in electron emission. In addition, the stability, mechanical properties, and the Raman and infrared (IR) activity modes of the MXenes are reported. Generally, functionalized MXenes would present smaller lattice parameters, lower free energies, and stronger mechanical strength compared to their counterparts. The data obtained may provide important theoretical ground for the investigations of the applications of MXenes.
Undergraduate degrees that train students for soil science careers at universities in the USA and its territories
Authors: Brevik Eric C. , Dolliver Holly , Edinger‐Marshall Susan , Itkin Danny , Johnson‐Maynard Jodi , Liles Garrett , Mbila Monday , Moorberg Colby , Sanchez‐de Leon Yaniria , Steffan Joshua J. , Ulery April , Vaughan Karen
Published: August 2020

Several soil science education studies over the last 15 yr have focused on the number of students enrolled in soil science programs. However, no studies have quantitatively addressed the number of undergraduate soil science preparatory programs that exist in the United States, which means we do not have solid data concerning whether overall program numbers are declining, rising, or holding steady. This also means we do not have complete data on the same trends for total undergraduate soil science students in the United States. This study used the US Office of Personnel Management (OPM) Soil Science Series 0470 standards to determine if a bachelor's degree met soil science preparatory criteria. Lists of the approximately 3,500 regionally accredited colleges and universities were obtained from the regional accrediting agencies; the website of each of the colleges and universities was visited to determine if they had a degree program that met the OPM 0470 criteria. Ninety‐two soil science preparatory degree programs were identified at 86 colleges and universities. These programs were primarily linked to (a) agriculture, (b) environmental science, and (c) soil and water science, based on the number of degree occurrences. This study creates a baseline for future studies that can investigate trends in soil science programs. It also provides an insight into the institutions and degree programs that should be included in soil science education studies.
Suppression of inflammation and fibrosis using soluble epoxide hydrolase inhibitors enhances cardiac stem cell-based therapy
Authors: Sirish Padmini , Thai Phung N. , Lee Jeong Han , Yang Jun , Zhang Xiao-Dong , Ren Lu , Li Ning , Timofeyev Valeriy , Lee Kin Sing Stephen , Nader Carol E. , Rowland Douglas J. , Yechikov Sergey , Ganaga Svetlana , Young Nilas , Lieu Deborah K. , Yamoah Ebenezer N. , Hammock Bruce D. , Chiamvimonvat Nipavan
Published: August 2020

Stem cell replacement offers a great potential for cardiac regenerative therapy. However, one of the critical barriers to stem cell therapy is a significant loss of transplanted stem cells from ischemia and inflammation in the host environment. Here, we tested the hypothesis that inhibition of the soluble epoxide hydrolase (sEH) enzyme using sEH inhibitors (sEHIs) to decrease inflammation and fibrosis in the host myocardium may increase the survival of the transplanted human induced pluripotent stem cell derived-cardiomyocytes (hiPSC-CMs) in a murine postmyocardial infarction model. A specific sEHI (1-trifluoromethoxyphenyl-3-(1-propionylpiperidine-4-yl)urea [TPPU]) and CRISPR/Cas9 gene editing were used to test the hypothesis. TPPU results in a significant increase in the retention of transplanted cells compared with cell treatment alone. The increase in the retention of hiPSC-CMs translates into an improvement in the fractional shortening and a decrease in adverse remodeling. Mechanistically, we demonstrate a significant decrease in oxidative stress and apoptosis not only in transplanted hiPSC-CMs but also in the host environment. CRISPR/Cas9-mediated gene silencing of the sEH enzyme reduces cleaved caspase-3 in hiPSC-CMs challenged with angiotensin II, suggesting that knockdown of the sEH enzyme protects the hiPSC-CMs from undergoing apoptosis. Our findings demonstrate that suppression of inflammation and fibrosis using an sEHI represents a promising adjuvant to cardiac stem cell-based therapy. Very little is known regarding the role of this class of compounds in stem cell-based therapy. There is consequently an enormous opportunity to uncover a potentially powerful class of compounds, which may be used effectively in the clinical setting.

Significance statement Stem cell replacement offers a great potential for cardiac regenerative therapy. However, there is a significant loss of transplanted stem cells from ischemia and inflammation in the host environment. This study demonstrates beneficial effects of inhibitors of soluble epoxide hydrolase (sEHI) in cell-based therapy using human induced pluripotent stem cell-derived cardiomyocytes in a preclinical model. sEHI results in a significant increase in the retention of transplanted stem cells and an improvement in cardiac function. Very little is known regarding this class of compounds in cell-based therapy. There is consequently an opportunity to uncover a potentially powerful class of inhibitors, which may be used in clinical settings.
Are the Sustainable Development Goals really sustainable? A policy perspective
Authors: Jain Prerna , Jain Pragati
Published: August 2020

Sustainable development seeks human well‐being without stretching the ecological limits. It is assumed that if sustainable development is aspired at global level, the goals prescribed should be within the planetary limits. A comparison of the scores of countries with respect to Sustainable Development Goal Index (SDGI) and scores on Ecological Footprints (EF) portrays quite a grim picture where countries with high EF have attained high scores on SDGI. A further investigation into the causal relationship between SDGI, Human Development Index (HDI) and EF reveals that SDGs are being achieved in an unsustainable manner. The environmental policy perspective of the total, direct and indirect effects of EF on SDGs estimated through path analysis unveils that the existing mode of achieving SDGs is at the cost of environmental degradation. SDGs have shown improvement through the improvement in the level of HDI, where human development is being attained in an environmentally unsustainable manner. The paper establishes that SDGs achieved are ecologically unjustifiable, and a reorientation of the existing patterns of human development well within the limits of ecological capacity of the earth is to be targeted.
Structure–Activity Relationship Study of T1R2/T1R3 Positive Allosteric Modulators and Evaluation of Their Enhancing Effect on Various Sweeteners
Authors: Matsumoto Ryo , Yamada Kei , Nakazawa Masakazu , Mori Suguru , Kitajima Seiji
Published: August 2020

The sweet taste receptor T1R2/T1R3 belongs to the family of G protein coupled receptors and recognizes various sweet substances from small compounds to proteins. We have previously reported unnatural tripeptides that function as positive allosteric modulators (PAMs) of the T1R2/T1R3. The structures were classified into three parts—head, linker, and tail—as compared with known T1R2/T1R3 PAMs. Here, we conducted a structure–activity relationship study of the tail structure to further understand the structural features of the T1R2/T1R3 PAMs. Moreover, we evaluated the enhancing effect of these PAMs on various sweeteners. In conclusion, we found that both hydrophilic α‐amino acids and the hydrophobicity of the α‐amino acid side chain are important for enhancing activity for this receptor. These PAMs also showed the receptor enhancing activity against sugar‐like T1R2/T1R3 agonists such as sucrose, sucralose, and fructose.
Thrombolytic Agents: Nanocarriers in Controlled Release
Authors: Hassanpour Soodabeh , Kim Han‐Jun , Saadati Arezoo , Tebon Peyton , Xue Chengbin , van den Dolder Floor W. , Thakor Jai , Baradaran Behzad , Mosafer Jafar , Baghbanzadeh Amir , de Barros Natan Roberto , Hashemzaei Mahmoud , Lee Kang Ju , Lee Junmin , Zhang Shiming , Sun Wujin , Cho Hyun‐Jong , Ahadian Samad , Ashammakhi Nureddin , Dokmeci Mehmet R. , Mokhtarzadeh Ahad , Khademhosseini Ali
Published: August 2020

Thrombosis is a life‐threatening pathological condition in which blood clots form in blood vessels, obstructing or interfering with blood flow. Thrombolytic agents (TAs) are enzymes that can catalyze the conversion of plasminogen to plasmin to dissolve blood clots. The plasmin formed by TAs breaks down fibrin clots into soluble fibrin that finally dissolves thrombi. Several TAs have been developed to treat various thromboembolic diseases, such as pulmonary embolisms, acute myocardial infarction, deep vein thrombosis, and extensive coronary emboli. However, systemic TA administration can trigger non‐specific activation that can increase the incidence of bleeding. Moreover, protein‐based TAs are rapidly inactivated upon injection resulting in the need for large doses. To overcome these limitations, various types of nanocarriers have been introduced that enhance the pharmacokinetic effects by protecting the TA from the biological environment and targeting the release into coagulation. The nanocarriers show increasing half‐life, reducing side effects, and improving overall TA efficacy. In this work, the recent advances in various types of TAs and nanocarriers are thoroughly reviewed. Various types of nanocarriers, including lipid‐based, polymer‐based, and metal‐based nanoparticles are described, for the targeted delivery of TAs. This work also provides insights into issues related to the future of TA development and successful clinical translation.
Expression of xenobiotic metabolising enzymes in lungs of horses with or without histological evidence of lower airway inflammation
Authors: Löfgren Maria , Larsson Pia , Lindberg Ronny , Hörnaeus Katarina , Tydén Eva
Published: August 2020

Mild, moderate and severe equine asthma is a problem for equine welfare. The aetiology of the disease is not known in detail but is likely multi‐factorial. One important factor may be inhaled dust which carries harmful substances which may be bioactivated and thus can lead to local inflammation in the airways. The aim of this study was to investigate gene expression and protein localisation of cytochrome P450 (CYP) enzymes, superoxide dismutase and glutathione‐S‐transferases (GST) involved in bioactivation and detoxification of harmful substances in lungs of horses with or without histological evidence of lower airway inflammation. Significantly lower gene expression of CYP2A13 and GSTM1 was observed in lungs from horses with histological evidence of lower airway inflammation compared with horses without. A higher expression, although not significant, was found for CYP1A1 in horses with histological evidence of lower airway inflammation. There were no differences in gene expression of GSTP1 and SOD3. The proteins were localised in the respiratory epithelium which is of relevance as a defence to local exposure of inhaled harmful substances. In conclusion, our study reports differential gene expression of enzymes involved in bioactivation and detoxification of foreign substances in the lungs of horses with histological evidence of lower airway inflammation compared with horses without.