bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Engineering of Isomeric Benzofurocarbazole Donors for Photophysical Management of Thermally Activated Delayed Fluorescence Emitters
Authors: Jung Mina , Lee Kyung Hyung , Lee Jun Yeob
Published: January 2020

Benzofurocarbazole moieties are commonly used donor structures in the design of thermally activated delayed fluorescence (TADF) emitters. However, only 5 H‐benzofuro[3,2‐c]carbazole (34BFCz) has been reported and, to the best of our knowledge, no other benzofurocarbazole derivatives have been covered in the literature. In the present study, two further benzofurocarbazole moieties, 12 H‐benzofuro[3,2‐a]carbazole (12BFCz) and 7 H‐benzofuro[2,3‐b]carbazole (23BFCz), have been synthesized to investigate the effect of the donor structure on the photophysics and device parameters of TADF emitters. Two benzofurocarbazole‐derived TADF emitters, 12‐(2‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐12 H‐benzofuro[3,2‐a]carbazole (o12BFCzTrz) and 7‐(2‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐7 H‐benzofuro[2,3‐b]carbazole (o23BFCzTrz), have been compared with 5‐(2‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐5 H‐benzofuro[3,2‐c]carbazole (oBFCzTrz). The benzofurocarbazole donor structure governs the TADF characteristics, such as charge‐transfer property and emission color. The 12BFCz donor has proved to be effective in blue‐shifting the emission color, and 34BFCz has proven useful for improving the external quantum efficiency (EQE). The 12BFCz‐derived o12BFCzTrz showed blue‐shifted color coordinates of (0.159, 0.288), compared to (0.178, 0388) for o23BFCzTrz and (0.169, 0.341) for oBFCzTrz. The 34BFCz‐derived oBFCzTrz exhibited an EQE of 22.9 %, compared to 19.2 % for o12BFCzTrz and 21.1 % for o23BFCzTrz.
Prognostic value of sleep apnea and nocturnal hypoxemia in patients with decompensated heart failure
Authors: Huang Yuhui , Wang Yunhong , Huang Yan , Zhai Mei , Zhou Qiong , Zhao Xuemei , Tian Pengchao , Ji Shiming , Zhang Chen , Zhang Yuhui , Zhang Jian
Published: January 2020

Background

Nocturnal hypoxemia is an important factor underlying the impact of sleep apnea on heart failure. It remains unclear whether nocturnal hypoxemia has a greater prognostic value in acute decompensated heart failure (ADHF) compared with the frequency of sleep apnea.

Hypothesis

Nocturnal hypoxemia might be better than the frequency of sleep apnea in predicting the outcomes in ADHF.

Methods

Sleep studies were prospectively performed during an ADHF hospitalization from January 2015 to December 2017. Sleep apnea was defined as the apnea‐hypopnea index (AHI) ≥15/h. The severity of nocturnal hypoxemia was determined by the percentage of time with saturation below 90% (T90%). The endpoint was the first event of all‐cause death, heart transplantation, implantation of left ventricular assist device, unplanned hospitalization for worsening heart failure, acute coronary syndrome, significant arrhythmias, or stroke.

Results

Of 382 patients, 189 (49.5%) had sleep apnea. The endpoint incidence did not differ between AHI categories (≥15/h vs <15/h: 52.4% vs 44.6%, log rank P = .353), but did between T90% categories (≥3.6% vs <3.6%: 54.5% vs 42.4%, log rank P = .023). Multivariate Cox regression analysis showed that T90% was independently associated with the endpoint (hazard ratio [HR] 1.008, 95% confidence interval [CI] 1.001‐1.016, P = .033), whereas AHI was not; the risk of the endpoint increased by 40.8% in patients with T90% ≥3.6% (HR 1.408, 95%CI 1.030‐1.925, P = .032).

Conclusion

Nocturnal hypoxemia had a greater prognostic value in ADHF than the frequency of sleep apnea.
A phase 1 trial of everolimus and bevacizumab in children with recurrent solid tumors
Authors: Santana Victor M. , Sahr Natasha , Tatevossian Ruth G. , Jia Sujuan , Campagne Olivia , Sykes April , Stewart Clinton F. , Furman Wayne L. , McGregor Lisa M.
Published: January 2020

Background

The prognosis for children with recurrent solid tumors generally is poor. Targeting mammalian target of rapamycin (mTOR) and vascular endothelial growth factor A with everolimus and bevacizumab, respectively, synergistically improves progression‐free survival and is well tolerated in adults with solid tumors.

Methods

In the current phase 1 study, a total of 15 children with recurrent or refractory solid tumors were treated with bevacizumab and everolimus to establish the maximum tolerated dose, toxicity, and preliminary antitumor response (ClinicalTrials.gov identifier NCT00756340). The authors also evaluated everolimus‐mediated inhibition of the mTOR pathway in the peripheral blood mononuclear cells of treated patients.

Results

Tumors predominantly were soft tissue and/or bone sarcomas (8 cases) and brain tumors (5 cases). The first 2 patients enrolled at dose level 1 (10 mg/kg of bevacizumab and 4 mg/m2 of everolimus) experienced dose‐limiting toxicities (DLTs). The next 5 patients were enrolled at dose level 0 (8 mg/kg of bevacizumab and 4 mg/m2 of everolimus), and DLTs occurred in 2 patients. The authors then modified the protocol to permit expansion of dose 0, and 8 additional patients were added, with no DLTs reported. Of all the patients, stable disease occurred in 4 patients (30.8%; median, 2 courses), and progressive disease occurred in 9 patients (69.2%). Overall survival was 0.59 years (95% CI, 0.24‐1.05 years). The mTOR biomarker phospho‐4EBP1 Thr/37/46 significantly decreased from baseline to day 27 in peripheral blood mononuclear cells (P = .045). Phospho‐AKT levels also decreased from those at baseline.

Conclusions

The maximum tolerated dose of cotreatment with bevacizumab and everolimus was 8 mg/kg of bevacizumab and 4 mg/m2 of everolimus in a 4‐week cycle for children with recurrent solid tumors.
On listening
Authors: Mack Jennifer W.
Published: January 2020

Communication is increasingly seen as fundamental to the work of medicine, but existing work largely focuses on what to say. Little work has focused on listening, a critically important but underappreciated skill.
Design of a CMOS 65‐nm inductor‐less VCO for ISM applications in the VHF band
Authors: Gaoding Ningcheng , Bousquet Jean‐François
Published: January 2020

This paper presents a design of a CMOS cross‐coupled voltage‐controlled oscillator (VCO) using active inductors (AIs) for wide‐band applications and can also be applied to various wireless technologies standards. The compatibility of this design to different wireless standards highlights its potential to be implemented at the core of the communication front end in the Internet of Things (IoT). The proposed AI design employs a gyrator‐C topology as the basic structure to generate an inductance. The VCO uses a cross‐coupled oscillator structure with a pair of varactors to sweep the frequency. Two extra capacitors, between the AIs and the outputs of the VCO core tank, are employed to enhance the performance of the phase noise and make the VCO work similarly to a linear transconductance (LiT) oscillator. Both the AIs and the VCO are designed in the TSMC 65‐nm CMOS technology, and the performance is analyzed using postsimulation results, as well as through measurements. The fundamental frequency spans from 140 to 463 MHz. Thus, the relative tuning range of this design is approximately 107%. The optimal phase noise of the design is around −97 dBc/Hz at 1‐MHz offset. Furthermore, it achieves an excellent figure of merit (FOM) around −163 dBc/Hz with a direct current (DC) power consumption less than 3 mW. The proposed design shows an advantage in phase noise and power consumption in comparison with previous active inductor VCO and ring VCO designs, respectively. The final layout occupies only 0.4 × 0.62 mm2 including the pads. The proposed AI‐VCO shows a compact size, linear tuning, low power consumption, and good phase noise performance.
Contemporary College Students’ Attitudes about Deception in Research
Authors: Lasser Jon , Ryser Gail , Borrego Dora , Ham Emma , Fierros Karla Reyes , Pruin Julia , Randolph Peyton
Published: January 2020

Given the widespread use of deception in psychological experiments and the frequent recruitment of college students as participants, scholars have taken an interest in the ways college students assess the potential costs and benefits of deception studies. It stands to reason that the engagement of participants not as mere subjects, but rather as participant partners, demands at least an awareness of how such participants consider the moral dimensions of deception. To this end, the present study replicates a project conducted almost 25 years ago to determine whether today's college students think about deception in research any differently than their counterparts did in the early 1990s. This article reviews some of the literature on deception, describes the original study conducted, and presents the results of the replication study.
Plant diversity effect on water quality in wetlands: a meta‐analysis based on experimental systems
Authors: Brisson Jacques , Rodriguez Mariana , Martin Charles A. , Proulx Raphaël
Published: January 2020

The ecological literature reports little empirical evidence from biodiversity–ecosystem functioning (BEF) experiments in wetland systems, even though wetlands are widely known for their water filtering capacity. Experiments comparing the effect of plant monocultures and mixtures on water quality to improve pollutant removal efficiency in treatment wetlands share the characteristics of classicalBEFexperiments, and so could provide insights for wetland management. To add to our understanding ofBEFrelationships in wetlands, we evaluated plant diversity effects on water purification through a meta‐analysis of freshwater experimental wetlands comparing monocultures to mixtures. We found 28 studies that matched our criteria forBEFanalysis, for a total of 561 diversity effects on pollutant removal. Overall, the meta‐analysis shows no significant effect of plant richness on removal of total suspended solids, but a positive effect on chemical oxygen demand and total nitrogen removal, and a marginal effect on phosphorus removal. Thus, the results of this meta‐analysis are consistent with reports of an overall positive biodiversity effect on ecosystem properties. An analysis of moderator variables shows that the experimental context (size of the experimental units, nutrient load, duration of the experiment) does not explain much of the residual variance. For pollutants that benefit from a positive plant richness effects on removal, mixtures do not perform better than the best monoculture. We found no evidence that plant richness effects are due to functional complementarity among species rather than to the presence of particularly efficient species. Complementarity effects may be less prevalent in highly productive, nutrient‐rich wetlands, compared to nutrient‐limited environments such as natural grasslands. Although findings must be confirmed by long‐term field experiments under natural conditions, result from experimental wetland systems may contribute to a better understanding of biodiversity effect on ecosystem functions in wetlands, in addition to guide practices in natural wetland restoration and the use of constructed wetlands for water treatment.
Evidence for a possible extinction debt in Swiss wetland specialist plants
Authors: Jamin Anine , Peintinger Markus , Gimmi Urs , Holderegger Rolf , Bergamini Ariel
Published: January 2020

Habitat loss leading to smaller patch sizes and decreasing connectivity is a major threat to global biodiversity. While some species vanish immediately after a change in habitat conditions, others show delayed extinction, that is, an extinction debt. In case of an extinction debt, the current species richness is higher than expected under present habitat conditions.

We investigated wetlands of the canton of Zürich in the lowlands of Eastern Switzerland where a wetland loss of 90% over the last 150 years occurred. We related current species richness to current and past patch area and connectivity (in 1850, 1900, 1950, and 2000). We compared current with predicted species richness in wetlands with a substantial loss in patch area based on the species‐area relationship of wetlands without substantial loss in patch area and studied relationships between the richness of different species groups and current and historical area and connectivity of wetland patches.

We found evidence of a possible extinction debt for long‐lived wetland specialist vascular plants: in wetlands, which substantially lost patch area, current species richness of long‐lived specialist vascular plants was higher than would have been expected based on current patch area. Additionally and besides current wetland area, historical area also explained current species richness of these species in a substantial and significant way. No evidence for an extinction debt in bryophytes was found.

The possible unpaid extinction debt in the wetlands of the canton of Zürich is an appeal to nature conservation, which has the possibility to prevent likely future extinctions of species through specific conservation measures. In particular, a further reduction in wetlands must be prevented and restoration measures must be taken to increase the number of wetlands.
Safety and efficacy of baroreflex activation therapy for heart failure with reduced ejection fraction: a rapid systematic review
Authors: Schmidt Rodrigo , Rodrigues Clarissa Garcia , Schmidt Kelen Heinrich , Irigoyen Maria Claudia Costa
Published: January 2020

To retrieve and assess the available data in the literature about the safety and efficacy of baroreflex activation therapy (BAT) in heart failure with reduced ejection fraction (HFrEF) patients, through a rapid systematic review of clinical studies. Rapid systematic review of literature. Searched electronic databases included PubMed, EMBASE, CENTRAL, Scopus, and Web of Science using Mesh and free terms for heart failure and BAT. No language restriction was used for the searches. We included full peer reviewed publications of clinical studies (randomized or not), including patients with HFrEF undergoing BAT, with or without control group, assessing safety and efficacy outcomes. One reviewer conducted the analysis of the selected abstracts and the full‐text articles, performed data extraction, and evaluated the methodological quality of the selected articles. The methodological quality was assessed according to the Cochrane Collaboration instruments. A descriptive summary of the results is provided. Of the 441 citations screened, 10 publications were included (three were only conference abstracts), reporting data from three studies. Only one study was a randomized clinical trial. Two studies reported a 6 month following, and the other study analysed outcomes up to 41 months. The procedure seems to be safe when performed by a well‐trained multi‐professional team. An 86% rate of system and procedure‐related complication‐free was reported, with no cranial nerve injuries. Improvements in New York Heart Association class of heart failure, quality of life, 6 min walk test, and hospitalization rates, as well as in muscle sympathetic nerve activity. No meta‐analysis was conducted because of the lack of homogeneity across studies; the results from each study are reported individually. BAT procedure seems to be safe if appropriate training is provided. Improvements in clinical outcomes were described in all included studies. However, several limitations do not allow us to make conclusive statements on the efficacy of BAT for HFrEF. New well‐designed trials are still needed.
Serum retinol‐binding protein 4 as a predictor of cardiovascular events in elderly patients with chronic heart failure
Authors: Li Xiu‐Zhen , Zhang Kang‐Zhen , Yan Jian‐Jun , Wang Li , Wang Yue , Shen Xi‐Yu , Sun Hui‐Xian , Liu Li , Zhao Can , He Hui‐Wei , Wang Lian‐Sheng , Gao Wei , Lu Xiang
Published: January 2020

Aims

RBP4 is an adipokine with adverse effects on cardiovascular system. Increased circulating retinol‐binding protein 4 (RBP4) has been linked to chronic heart failure (CHF). However, whether elevated RBP4 is correlated with a poor prognosis in elderly patients with CHF remains unclear. The aim of this study was to evaluate the prognostic value of serum RBP4 in elderly patients with CHF.

Methods and results

We enrolled 934 consecutive elderly patients (aged 60 years and older) with CHF and 138 age‐matched and sex‐matched control subjects in a prospective cohort study and explored the association of serum RBP4 levels with the clinical outcomes using multivariate Cox regression analyses. Serum RBP4 levels were elevated in CHF patients when compared with controls (46.66 ± 12.38 μg/mL vs. 40.71 ± 7.2 μg/mL, P < 0.001). Patients with the highest RBP4 concentrations had higher N terminal pro brain natriuretic peptide (NT‐proBNP) levels but lower left ventricular eject fraction (LVEF) and estimated glomerular filtration rate (P < 0.001). Serum RBP4 levels were increased as the New York Heart Association functional class increased and LVEF decreased (P < 0.001) and were negatively correlated with LVEF (r = −0.154, P < 0.001) but positively correlated with NT‐proBNP levels (r = 0.074, P = 0.023). Multivariate Cox regression analysis suggested that log RBP4 was an independent predictor for major adverse cardiac event(s) [hazard ratio (HR) = 2.61, 95% confidence interval (CI) = 1.19–5.70], together with age, male, LVEF, log NT‐proBNP, and estimated glomerular filtration rate. Moreover, log RBP4 was also an independent predictor for cardiovascular mortality (HR = 2.24, 95% CI = 1.35–5.39) and CHF rehospitalization (HR = 2.54, 95% CI = 1.09–5.60) even after adjustment for the established adverse prognostic factors for CHF. The Kaplan–Meier survival curves showed that high concentration of RBP4 was a prognostic indicator of major adverse cardiac event(s) in patients with CHF.

Conclusions

Our findings demonstrate for the first time that elevated serum RBP4 is correlated with worse outcome in elderly patients with CHF.
Cascade Synthesis of 4‐Arylcoumarins: Pd‐Catalyzed Arylations and Cyclizations with (E)‐Ethyl 3‐(2‐Hydroxyaryl)acrylates and Triarylantimony Difluorides
Authors: Kitamura Yuki , Matsumura Mio , Kato Yukari , Murata Yuki , Yasuike Shuji
Published: January 2020

Herein, we describe a simple general method for the synthesis of 4‐arylcoumarins using pentavalent organoantimony compounds. The reactions of 3‐(2‐hydroxyaryl)acrylates with triarylantimony difluorides in the presence of Pd(OAc)2 (10 mol‐%) and 2,2'‐bipyridyl (10 mol‐%) at 80 °C under aerobic conditions afforded 4‐arylcoumarins in good‐to‐excellent yields. This protocol involves a cascade oxidative Heck‐type arylation followed by cyclization, with all the aryl groups in the triarylantimony difluoride transferred to the coupling products. Triarylantimony difluorides resulted in better outcomes than those obtained with other pentavalent organoantimony or bismuth compounds.
Diboron‐Mediated Rhodium‐Catalysed Transfer Hydrogenation of Alkenes and Carbonyls
Authors: Lin Xiao , Wang Yuhan , Hu Yan , Zhu Wanjiang , Dou Xiaowei
Published: January 2020

A diboron‐mediated rhodium‐catalysed transfer hydrogenation system using water as the hydrogen donor is developed. In addition to a series of alkenes with good functional group tolerance, this rhodium‐based catalytic system also effectively reduces aldehydes and ketones. A plausible mechanism involving the RhI‐catalysed hydrogen generation and Rh0‐catalysed hydrogenation is proposed for the reaction.
A study of effects on economic indicators for different heat source temperature on thermal storage‐based solar organic Rankine cycle system
Authors: Baral Suresh
Published: January 2020

The solar organic Rankine cycle (ORC) system for power generation with thermal storage type may be one of the promising technologies for prolonging power generation. The thermal storage type of solar ORC system is feasible for investment due to higher power production. In addition, the heat source temperature of the ORC system plays an important role in the investment. The main aim of the study is to investigate the solar ORC with thermal storage systems from the thermoeconomic point of view. The paper provides recommendations for a suitable class of investment in which an ORC system can be economically feasible. Besides, the economics and thermoeconomic analysis is carried out in order to find the cost of electricity production from the solar ORC under various solar source temperatures. The cost of electricity generation is found to be in the range of $0.2/kWh to $0.6/kWh for 120°C and 90°C, respectively. For analysis, different financial scenarios are developed based on the total cost of the solar ORC units. The economic parameters, such as payback period, internal rate of return (IRR) and specific investment cost, are calculated. The payback period is found to be less than 6 years for the thermal storage type of solar ORC system with the IRR to be 15%. This shows that the investment is feasible for medium and large scale solar ORC with thermal storage systems.
Sparse support vector machine with pinball loss
Authors: Tanveer M. , Sharma S. , Rastogi R. , Anand P.
Published: January 2020

The standard support vector machine (SVM) with a hinge loss function suffers from feature noise sensitivity and instability. Employing a pinball loss function instead of a hinge loss function in SVMs provides noise insensitivity to the model as it maximizes the quantile distance. However, the pinball loss function simultaneously causes the model to lose sparsity by penalizing correctly classified samples. To overcome the aforementioned shortcomings, we propose a novel sparse SVM with pinball loss (Pin‐SSVM) for solving classification problems. The proposed Pin‐SSVM employs L1‐norm in the SVM classifier with the pinball loss (Pin‐SVM), which ensures the robustness, sparseness, and noise insensitivity of the model. The proposed Pin‐SSVM eradicates the need to solve the dual as we simply obtain its solution by solving a linear programming problem (LPP). The proposed Pin‐SSVM does not spend more computational time as that of Pin‐SVM. Hence, solving an LPP with two linear inequality constraints does not affect the computational complexity. The numerical experiments on several real‐world benchmark noise corrupted and imbalanced UCI datasets demonstrate that the proposed Pin‐SSVM is suitable for noisy and imbalanced data sets, and in most cases, outperforms the results of the baseline models.
Rapid detection of Atlantic salmon multi‐quality based on impedance properties
Authors: Sun Zongbao , Liang Liming , Li Junkui , Liu Xiaoyu , Sun Jian , Zou Xiaobo , Zuo Min , Guo Zhiming
Published: January 2020

To establish a rapid, convenient, and low‐cost method to assess the quality of Atlantic salmon, we analyzed the impedance between 10–1 and 105 Hz for Atlantic salmon/rainbow trout, chilled/frozen‐thawed salmon, and fresh/stale salmon. We combined chemometrics with impedance properties to create a multi‐quality index for Atlantic salmon. The accuracy of all three models established can reach 100% in distinguishing Atlantic salmon from rainbow trout and distinguishing chilled salmon from frozen‐thawed salmon. We applied a partial least squares method to create a quantitative prediction model of bioimpedance spectroscopy and the value of total volatile basic nitrogen. The correlation coefficients of the training and test sets were 0.9447 and 0.9387. Our results showed that the combination of impedance properties and chemometrics was a simple and effective application to evaluate Atlantic salmon quality.
Demand for self‐tests: Evidence from a Becker–DeGroot–Marschak mechanism field experiment
Authors: Aylward Patrick , Essendi Hildah , Little Kristen , Wilson Nicholas
Published: January 2020

Self‐tests offer one approach for reducing frictions underlying low demand for preventive health inputs, yet there is little evidence on demand for self‐tests. We used the Becker–DeGroot–Marschak mechanism—an incentive‐compatible approach—to elicit exact willingness to pay (WTP) for HIV self‐tests in a field experiment with 822 participants at 66 health clinics/pharmacies in Kenya. Our analysis reveals substantial demand at low prices and highly elastic demand at a wide range of prices above this range. We find few participants with nonpositive WTP. We examine correlates of WTP and discuss policy and research implications of our findings.
Evaluation of hydrologic impact of an irrigation curtailment program using Landsat satellite data
Authors: Velpuri Naga Manohar , Senay Gabriel B. , Schauer Matthew , Garcia C. Amanda , Singh Ramesh K. , Friedrichs MacKenzie , Kagone Stefanie , Haynes Jonathan , Conlon Terrence
Published: January 2020

Upper Klamath Lake (UKL) is the source of the Klamath River that flows through southern Oregon and northern California. The UKL Basin provides water for 81,000+ ha (200,000+ acres) of irrigation on the U.S. Bureau of Reclamation Klamath Project located downstream of the UKL Basin. Irrigated agriculture also occurs along the tributaries to UKL. During 2013–2016, water rights calls resulted in various levels of curtailment of irrigation diversions from the tributaries to UKL. However, information on the extent of curtailment, how much irrigation water was saved, and its impact on the UKL is unknown. In this study, we combined Landsat‐based actual evapotranspiration (ETa) data obtained from the Operational Simplified Surface Energy Balance model with gridded precipitation and U.S. Geological Survey station discharge data to evaluate the hydrologic impact of the curtailment program. Analysis was performed for 2004, 2006, 2008–2010 (base years), and 2013–2016 (target years) over irrigated areas above UKL. Our results indicate that the savings from the curtailment program over the June to September time period were highest during 2013 and declined in each of the following years. The total on‐field water savings was approximately 60 hm3 in 2013 and 2014, 44 hm3 in 2015, and 32 hm3 in 2016 (1 hm3 = 10,000 m3 or 810.7 ac‐ft). The instream water flow changes or extra water available were 92, 68, 45, and 26 hm3, respectively, for 2013, 2014, 2015, and 2016. Highest water savings came from pasture and wetlands. Alfalfa showed the most decline in water use among grain crops. The resulting extra water available from the curtailment contributed to a maximum of 19% of the lake inflows and 50% of the lake volume. The Landsat‐based ETa and other remote sensing datasets used in this study can be used to monitor crop water use at the irrigation district scale and to quantify water savings as a result of land‐water management changes.
Technology‐related factors and their influence on turnover intentions: A case of government employees in South Africa
Authors: Mahlasela Samkelisiwe , Chinyamurindi Willie T.
Published: January 2020

The purpose of this article is to investigate the influence of technology‐related factors on the turnover intentions of a sample of government employees in South Africa. Technology‐related factors, as argued in the literature, consist of (a) technology‐based job autonomy, (b) technology‐based job overload and (c) technology‐based job monitoring. The backdrop of this study is twofold. First, technology is argued as a central feature to work especially amongst employees in the digital age. Second, the rate at which employees leave their jobs appears to be on the increase, especially within the South African public service. These two factors provide the impetus to our focus on studying turnover intentions. Using a sample of 186 government employees in the Eastern Cape Province of South Africa, a self‐administered questionnaire was deployed. The findings revealed that when employees experience technology‐based job autonomy this did not necessarily result in them having the intention to leave their work. Further, the findings also indicate and show support to the model being tested in that technology factors like: (a) technology‐based job overload and (b) technology‐based monitoring influence employee intentions to leave their work. Based on the findings of the research, recommendations and implications concerning theory and practice are made.
Electrospun poly(d,l‐lactide)/gelatin/glass‐ceramics tricomponent nanofibrous scaffold for bone tissue engineering
Authors: Bochicchio Brigida , Barbaro Katia , De Bonis Angela , Rau Julietta V. , Pepe Antonietta
Published: January 2020

Electrospun scaffolds are emerging as extracellular matrix (ECM)mimicking structures for tissue engineering thanks to their nanofibrous architecture. For the development of suitable electrospun scaffolds for bone tissue engineering, the addition of inorganic components has been implemented with the aim to confer important bioactivity like osteoinduction, osteointegration, and cell adhesion to the scaffolds. In this context, we propose a tricomponent electrospun scaffold composed of poly(d,l‐lactide), gelatin and RKKP glass‐ceramics. The bioactive RKKP glass‐ceramic system has attracted interest, due to the presence of ions such as La3+ and Ta5+, which turned out to be valuable as growth supporting agents for bones. In this work, RKKP glass‐ceramics were embedded inside the microfibers of electrospun scaffolds and the structural and biological properties were investigated. Our results showed that the glass‐ceramic microparticles were uniformly distributed in the fibrous structure of the scaffold. Furthermore, the glass‐ceramics promoted biomineralization of the scaffolds and improved cell viability and osteogenic differentiation. The mineralized layer formed on RKKP‐containing scaffolds after incubation in simulated body fluid medium has been shown to be hydroxyapatite by Raman spectroscopy and X‐ray diffraction. The results on differentiation studies of canine adipose‐derived mesenchymal stem cells grown on the electrospun scaffolds suggest that on varying the content of RKKP in the scaffold, it is possible to drive the differentiation toward chondrogenic or osteogenic commitment. The presence of ions, like La3+ and Ta5+, in the RKKP embedded polymeric composite scaffolds could play a role in supporting cell growth and promoting differentiation.
Improved tissue integration of a new elastic intraperitoneal stoma mesh prosthesis
Authors: Eickhoff Roman , Heise Daniel , Kroh Andreas , Helmedag Marius , Klinge Uwe , Neumann Ulf P. , Klink Christian D. , Lambertz Andreas
Published: January 2020

Parastomal herniation is a frequent complication in colorectal surgery, occurring with a prevalence of 30–80%. The aim of the study was to create a new intraperitoneal colostoma mesh prosthesis (IPST) with enhanced elastic properties made with thermoplastic polyurethane (TPU) monofilaments. We performed open terminal sigmoid colostomies reinforced with either a 10 cm by 10 cm polyvinylidene fluoride (PVDF) or a new TPU/PVDF composite mesh in a total of 10 minipigs. Colostoma was placed paramedian in the left lower abdomen and IPST meshes were fixed intraperitoneal. After 8 weeks, the animals were euthanized after laparoscopic exploration and specimen were explanted for histological investigations. Implantation of a new IPST‐mesh with enhanced elastic properties was feasible in a minipig model within an observation period of 8 weeks. Immunohistochemically, Collagen I/III ratio as a marker of tissue integration was significantly higher in TPU‐group versus PVDF group (9.4 ± 0.5 vs. 8.1 ± 0.5, p = 0.002) with a significantly lower inflammatory reaction measured by a smaller inner granuloma at mesh–colon interface (17.6 ± 3.3 μm vs. 23 ± 5 μm, p < 0.001). A new TPU/PVDF composite mesh with enhanced elastic properties as IPST was created. Stoma surgery and especially the evaluation of the new stoma mesh prosthesis are feasible with reproducible results in an animal model. Tissue integration expressed by Collagen I/III ratio seems to be improved in comparison to standard‐elastic PVDF‐IPST meshes.
Development of an automated micropipette coating method for drug‐coated balloons
Authors: Fuglsby Kirby , Anderson Jordan A. , Engebretson Daniel , Lamichhane Sujan
Published: January 2020

Drug‐coated balloons (DCBs) are a recent technology developed to treat peripheral artery disease (PAD). Along with a suitable formulation of antiproliferative drug and excipient, coating method is an important aspect of a DCB as these factors affect coating characteristics and drug delivery to the treatment site. The multiple release tailored medical devices DCB (MR‐TMD‐DCB), designed to achieve multiple inflations to treat complex PAD, contains paclitaxel (PAT) as the antiproliferative drug and polyethylene oxide (PEO) as the excipient. In our previous studies, the MR‐TMD‐DCB was coated using a manual dip coating method. In this study, an automated micropipette coating method was developed using a modified spray coating instrument to coat the MR‐TMD‐DCB. First, the coating formulation and strategy was optimized. A drug formulation of 16 wt% PAT and 4% wt/vol PEO, a polymer formulation of 2.5% wt/vol PEO, and a total of two drug layers produced a mostly uniform and thin coating with no defects and acceptable drug load. The balloon also had optimal drug uptake in arterial tissue in an in vitro flow model. Next, the reproducibility of the coating strategy was improved by optimizing the instrument parameters. The optimized instrument parameters (translational speed = 0.150 in/s, revolution rate = 100 rpm, flow rate = 0.6 ml/min) resulted in improved reproducibility of the drug load and similar coating properties as the DCB. This study demonstrated the ability to automate the micropipette process to obtain a balloon with optimal coating properties and drug tissue uptake.
Fabrication, characterization, and in vitro evaluation of electrospun polyurethane‐gelatin‐carbon nanotube scaffolds for cardiovascular tissue engineering applications
Authors: Tondnevis Farbod , Keshvari Hamid , Mohandesi Jamshid Aghazadeh
Published: January 2020

Myocardial infarction occurs because coronary arteries insufficiency is one of the major causes of mortality worldwide. Recent studies have shown that tissue engineering of myocardial tissue to regenerate infarcted tissue or engineering of the coronary artery may help overcome this problem. In the present research, gelatin and single‐walled carbon nanotube were firstly administrated to physico‐chemically and biologically modulate polyurethane nanofibers. Electrospinning, as versatile and effective technique for production of functional nanoscale fiber, was applied. Incorporation of both gelatin and SWNTs reduced mean diameter of nanofibrous scaffolds from 210 to 140 nm, which influenced on initial cell behavior. Possible interaction between gelatin and SWNTs with polyurethane chains was evaluated using FTIR and DSC techniques. Regarding the incorporation of both gelatin and SWNTs, it was found that hydrophilicity of nanofibrous scaffolds dramatically improved. Scaffold degradation profile was adjusted by incorporation of gelatin. Biomimetic mechanical properties of composite scaffolds like normal blood vessel were developed and SWNTs improved the Young modulus and ultimate strength of scaffolds up to 16.47 ± 0.5 and 23.73 ± 0.5 MPa, respectively. However, addition of gelatin increased elongation at break due to its softening effect. The incorporation of the SWNTs led to significant enhancement of electrical conductivity of the scaffolds. Biological evaluation using SEM and MTT assay demonstrated that nanofibrous surface was covered by confluent and dense layer of both myocardial myoblast and endothelial cells after 7 days of culture, which is crucial for cardiovascular tissue engineering. Results verified that the fabricated scaffolds could be effective for cardiovascular tissue engineering.
Assessment of the protective and therapeutic effect of melatonin against thioacetamide‐induced acute liver damage
Authors: Sayan Meryem , Karabulut Derya , Özdamar Saim
Published: January 2020

Acute or chronic damage to the liver may occur through alcohol, drugs, viruses, genetic disorders, and toxicity. In this study, we planned to investigate the protective and therapeutic effects of melatonin (Mel) by causing damage to the liver with thioacetamide (TAA). Thirty‐five rats were used. Group I: control group (seven pieces), group II: Mel group (seven pieces) the single dose on the first day of the experiment was 10 mg/kg, group III: TAA (seven pieces) 300 mg/kg with 24‐hour intervals, two doses, group IV: Mel + TAA group (seven pieces) 10 mg/kg single dose Mel was applied 24  hours before TAA application, group V: TAA + Mel group (seven pieces) single dose (24th hour) of 10 mg/kg Mel was administered after TAA (300 mg/kg) two doses. The liver histology was evaluated. Apoptosis, autophagy, and necrosis markers in tissue were determined by immunohistochemistry. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) levels in blood serum samples and transforming growth factor‐β (TGF‐β) and tumor necrosis factor‐α (TNF‐α) levels were determined in liver tissue. TAA affected histologically the classical lobule structure both in cell cords and sinusoids. Caspase‐3, RIP3, and LC3 levels were increased in group III compared with the control group. TAA did not cause a statistically significant change in TNF‐α level but decreased the TGF‐β level significantly. AST and ALT levels were statistically significant in group II and V compared with group I, the ALP level was significant in group IV compared with group II. The results of this study showed that TAA caused significant damage to tissues and increased cell death, Mel was found to have more therapeutic than the protective effect on tissues.
Excited‐state intramolecular proton transfer driven by conical intersection in hydroxychromones
Authors: Anand Neethu , Isukapalli Sai Vamsi Krishna , Vennapusa Sivaranjana Reddy
Published: January 2020

Nonradiative decay pathways associated with vibronically coupled S1(ππ*)–S2(nπ*) potential energy surfaces of 3‐ and 5‐hydroxychromones are investigated by employing the linear vibronic coupling approach. The presence of a conical intersection close to the Franck–Condon point is identified based on the critical examination of computed energetics and structural parameters of stationary points. We show that very minimal displacements of relevant atoms of intramolecular proton transfer geometry are adequate to drive the molecule toward the conical intersection nuclear configuration. The evolving wavepacket on S1(ππ*) bifurcates at the conical intersection: a part of the wavepacket moves to S2(nπ*) within a few femtoseconds while the other decays to S1 minimum. Our findings indicate the possibility of forming the proton transfer tautomer product via S2(nπ*), competing with the traditional pathway occurring on S1(ππ*).
Identification of and solution for false D‐dimer results
Authors: Zhang Xian‐Yan , Zhang Xue‐Xuan , Xu Jia‐Long , Huang Teng‐Yi , Wu Ying , Yang Ye‐Ru , Zhou Huan‐Bin , Wu Ying‐E
Published: January 2020

Background

Clinically, D‐dimer (DD) levels are mainly used to exclude diseases such as deep venous thrombosis (DVT). In clinical testing, DD assays can be subjected to interference that may cause false results, which directly affect the clinical diagnosis. Our hypothesis was that the 95% confidence intervals (CIs) of the fibrin degradation product (FDP)/DD and fibrinogen (Fib)/DD ratios were used to identify these false results and corrected via multiple dilutions.

Methods

In total, 16 776 samples were divided into three groups according to the DD levels detected by Sysmex CS5100 and CA7000: Group A, DD ≥ 2.0 μg/mL fibrinogen equivalent unit (FEU); group B, 0.5 < DD < 2.0 μg/mL FEU; and group C, DD ≤ 0.5 μg/mL FEU. The 95% CIs of the FDP/DD and Fib/DD ratios were calculated. Six abnormal DD results were found according to the 95% CIs. For verification, we performed multiple dilutions, compared the results with those of other instruments, and tested the addition of heterophilic blocking reagent (HBR).

Results

The median and 95% CI of the FDP/DD ratio were 3.76 and 2.25‐8.15 in group A, 5.63 and 2.86‐10.58 in group B, 10.23 and 0.91‐47.71 in groups C, respectively. For the Fib/DD ratio, the 95% CIs was 0.02‐2.21 in group A, 0.68‐8.15 in group B, and 3.82‐55.27 in groups C. Six abnormal results were identified after multiple dilutions, by comparison with other detection systems, and after HBR addition.

Conclusions

The FDP/DD ratio is more reliable for identifying false results. If the FDP/DD ratio falls outside the 95% CI, it should be verified by different methods.
Deceased vs living donor grafts for pediatric simultaneous liver‐kidney transplantation: A single‐center experience
Authors: Gautier Sergey , Monakhov Artem , Tsiroulnikova Olga , Voskanov Mikhail , Miloserdov Igor , Dzhanbekov Timur , Meshcheryakov Sergey , Latypov Robert , Chekletsova Elena , Malomuzh Olga , Khizroev Khizri , Dzhiner Deniz , Pashkova Irina
Published: January 2020

Introduction

In conditions of limited experience of pediatric simultaneous liver‐kidney transplantation (SLKT) using grafts from living and deceased donors, there is a certain need to validate the approach.

Patients

The retrospective study of 18 pediatric patients who received SLKT between 2008 and 2019.

Results

Grafts were obtained from both living and deceased donors. The patients’ age ranged from 2 to 16 years (9 years ±4). The body weight of the children varied from 9.5 to 39 kg (22 kg ±9). The follow‐up period lasted from 1 to 109 months (median 38 months ±35). The various graft combinations were used in both groups. There was no mortality during the follow‐up. There was no significant difference in baseline parameters in recipients who received grafts from living and deceased donors except age (7.5 years ±2.2 vs 11.8 years ±4.1; P = .038). Rate of complications > grade II was higher among recipients of deceased donor SLKT (7.7% vs 60%; OR, 7.8; 95% CI, 1.04‐58.48; P = .044). All the patients are alive with both grafts functioning. All the living donors returned to the normal life.

Conclusion

SLKT is a safe and effective procedure for children with both simultaneous end‐stage liver disease and end‐stage renal disease. Both living donor partial liver and kidney transplantation and deceased donor liver‐kidney transplantation can be considered as safe and feasible options.
AdipoRon, a new therapeutic prospect for Duchenne muscular dystrophy
Authors: Abou‐Samra Michel , Selvais Camille M. , Boursereau Raphael , Lecompte Sophie , Noel Laurence , Brichard Sonia M.
Published: January 2020

Background

Adiponectin (ApN) is a hormone known to exhibit insulin‐sensitizing, fat‐burning, and anti‐inflammatory properties in several tissues, including the skeletal muscle. Duchenne muscular dystrophy (DMD) is a devastating disease characterized by dystrophin deficiency with subsequent chronic inflammation, myofiber necrosis, and impaired regeneration. Previously, we showed that transgenic up‐regulation of ApN could significantly attenuate the dystrophic phenotype in mdx mice (model of DMD). Recently, an orally active ApN receptor agonist, AdipoRon, has been identified. This synthetic small molecule has the advantage of being more easily produced and administrable than ApN. The aim of this study was to investigate the potential effects of AdipoRon on the dystrophic muscle.

Methods

Four‐week‐old mdx mice (n = 6–9 per group) were orally treated with AdipoRon (mdx‐AR) for 8 weeks and compared with untreated (mdx) mice and to control (wild‐type) mice. In vivo functional tests were carried out to measure the global force and endurance of mice. Ex vivo biochemical and molecular analyses were performed to evaluate the pathophysiology of the skeletal muscle. Finally, in vitro tests were conducted on primary cultures of healthy and DMD human myotubes.

Results

AdipoRon treatment mitigated oxidative stress (−30% to 45% for 4‐hydroxy‐2‐nonenal and peroxiredoxin 3, P < 0.0001) as well as inflammation in muscles of mdx mice (−35% to 65% for interleukin 1 beta, tumour necrosis factor alpha, and cluster of differentiation 68, a macrophage maker, P < 0.0001) while increasing the anti‐inflammatory cytokine, interleukin 10 (~5‐fold, P < 0.0001). AdipoRon also improved the myogenic programme as assessed by a ~2‐fold rise in markers of muscle proliferation and differentiation (P < 0.01 or less vs. untreated mdx). Plasma lactate dehydrogenase and creatine kinase were reduced by 30–40% in mdx‐AR mice, reflecting less sarcolemmal damage (P < 0.0001). When compared with untreated mdx mice, mdx‐AR mice exhibited enhanced physical performance with an increase in both muscle force and endurance and a striking restoration of the running capacity during eccentric exercise. AdipoRon mainly acted through ApN receptor 1 by increasing AMP‐activated protein kinase signalling, which led to repression of nuclear factor‐kappa B, up‐regulation of utrophin (a dystrophin analogue), and a switch towards an oxidative and more resistant fibre phenotype. The effects of AdipoRon were then recapitulated in human DMD myotubes.

Conclusions

These results demonstrate that AdipoRon exerts several beneficial effects on the dystrophic muscle. This molecule could offer promising therapeutic prospect for managing DMD or other muscle and inflammatory disorders.
Renewal and resurgence phenomena generalize to Amazon's Mechanical Turk
Authors: Robinson Théo P. , Kelley Michael E.
Published: January 2020

Amazon's Mechanical Turk (MTurk) is a crowdsourcing platform that provides researchers with the potential for obtaining behavioral data for very little cost. However, the extent to which the results of common behavioral phenomena found in basic, translational, and applied laboratories may be reproduced (as a first step towards prospective research) via MTurk remains relatively unexplored. We evaluated renewal and resurgence arrangements using MTurk as the subject recruitment platform as a first step to determining the generality of the obtained data. Results suggested that MTurk participants produced renewal and resurgence data similar to those reported in basic, translational, and applied studies.
Microstructural characterization of plasma sprayed Ln2Zr2O7 thermal barrier coatings by electron microscopy methods
Authors: Moskal Grzegorz
Published: January 2020

The presented article characterized microstructural aspects of thermal barrier coatings (TBCs) analysis using methods of electron microscopy such as electron backscatter diffraction (EBSD), transmission/scanning electron microscopy (S/TEM), and TEM. The analyzed TBC system is based on gadolinium zirconate deposited by air plasma spraying method, and additionally, it was subjected to an oxidation test for 500 hr at a temperature of 1,100°C. Moreover, the morphological characterization of feedstock powder was showed. EBSD analysis revealed the inhomogeneity of feedstock materials in the form of complex phase composition. In the case of deposited coating, this method was used to characterize the crystallite size of zirconate coating and phase composition of thermally grown oxide zone. S/TEM and TEM analysis showed morphological details of this zone but not revealed such phase as perovskite oxide of GdAlO3 type.