bluuebunny/crossref_metadata_2025 huggingface dataset:
MicroRNA‐936/ERBB4/Akt axis exhibits anticancer properties of gastric cancer through inhibition of cell proliferation, migration, and invasion
Authors: Liu Shi , Gong Ying , Xu Xue‐Dong , Shen Hui , Gao Shuai , Bao Hai‐Dong , Guo Shi‐Bin , Yu Xue‐Feng , Gong Jian
Published: October 2020

Gastric cancer is one of the most common cancers globally and has a poor prognosis. MiR‐936 has been reported to regulate cell activity and tumor progression in non‐small cell lung cancer, glioma, and epithelial ovarian cancer. However, the specific role and mechanism of miR‐936 in gastric cancer have not been explored. In present study, gastric cancer cells were transfected with miR‐936 mimic, and cell proliferation, cell cycle distribution, cell apoptosis, migration and invasion were assessed via cell‐counting kit‐8, flow cytometry, wound healing, and transwell assay, respectively. Dual luciferase reporter assay was used to check miR‐936 binding to its downstream target. It was shown that miR‐936 was downregulated in gastric cancer tissues and cells. Erb‐B2 Receptor Tyrosine Kinase 4 (ERBB4) was confirmed as a direct target of miR‐936 and negatively regulated its expression by miR‐936. Overexpression of miR‐936 suppressed cell proliferation, cell cycle progression, cell migration and invasion, and enhanced cell apoptosis in gastric cancer cells, which could be reversed by further ERBB4 overexpression. Western blot results showed that miR‐936/ERBB4 axis regulated Akt‐related pathways to control gastric cancer cell activities. Therefore, our data suggest that miR‐936 overexpression inhibits cell proliferation and invasion and promotes cell apoptosis through Akt‐related pathways by targeting ERBB4, which provides novel insight to target miR‐936 or miR‐936/ERBB4 axis for the treatment of gastric cancer.
Cullin 4B regulates cell survival and apoptosis in clear cell renal cell carcinoma as a target of microRNA‐217
Authors: Yang Hai‐Feng , Wang Zheng‐Liang , Mao Ting‐Ting , Liu Jian‐Chang
Published: October 2020

Cullin 4B (CUL4B) was reported to be closely related to the progression of some tumors, but its function in clear cell renal cell carcinoma (ccRCC) has not been reported. Our present study found CUL4B was upregulated in ccRCC, and CUL4B knockdown markedly inhibited ccRCC cell growth and induced apoptosis. In addition, CUL4B knockdown markedly inhibited antiapoptotic proteins' expression in ccRCC cells, including Mcl‐1 and Bcl‐2, and silenced CUL4B also induced the cleavages of PARP, an important index of apoptosis. We also confirmed microRNA‐217 (miR‐217) was downregulated in ccRCC tumor tissues, and negatively correlated with CUL4B expression. Further investigations revealed miR‐217 targeted CUL4B and markedly inhibited its expression in ccRCC cells. In addition, overexpression of miR‐217 by mimics significantly suppressed ccRCC cell growth. In contrast, enforced expression of CUL4B significantly abolished miR‐217‐induced cell survival inhibition in ccRCC cells. In conclusion, our present results suggested targeting miR‐217‐CUL4B axis would be a promising strategy for ccRCC treatment.
Missed nursing care: An overview of reviews
Authors: Chaboyer Wendy , Harbeck Emma , Lee Bih‐O , Grealish Laurie
Published: October 2020

Missed nursing care is care that is delayed, partially completed, or not completed at all. The aim of this overview of reviews was to identify the nursing care that is missed, the factors that influence missed nursing care and the outcomes from it. To be included, reviews had to use the systematic review process and focus on hospital care. Databases were searched from inception until August sixth, 2020. One author screened the papers and extracted data on included reviews and a second checked this. Two authors independently assessed the quality of the reviews. Seven reviews were included in this overview. Categories of care missed included: (a) communication and information sharing; (b) self‐management, autonomy, and education including care planning, discharge planning and decision; (c) fundamental physical care; and (d) emotional and psychological care including spiritual support. Factors associated with missed care were related to staffing levels and/or labor resources skill mix, material resources not being available, patient acuity and teamwork/communication. Outcomes of missed nursing care included: less/poorer quality of patient care, patient satisfaction, and nurses' job satisfaction, increased patient adverse events, and the organizational outcomes of increasing hospital length of stay and hospital readmission. In‐depth qualitative and mixed methods research is needed to better understand how nurses prioritize care and why care is missed. Longitudinal and experimental research is required to better clarify if these relationships between missed care and negative patient outcomes are likely cause and effect.
Use of remote sensing to track postindustrial vegetation development
Authors: Woźniak Gabriela , Dyderski Marcin K. , Kompała‐Bąba Agnieszka , Jagodziński Andrzej M. , Pasierbiński Andrzej , Błońska Agnieszka , Bierza Wojciech , Magurno Franco , Sierka Edyta
Published: October 2020

The effects of natural processes on deposited mineral material of postindustrial sites is underestimated. Natural vegetation development on mineral material substratum is an unappreciated way of site management. Due to the classification‐based approach to assembly of plant community diversity, remote sensing methods have limited application. We aimed to assess whether remotely sensed data allow for building predictive models, able to recognise vegetation variability along the main gradients of species composition. We assessed vegetation in 321 study plots on four coal‐mine spoil heaps in Silesia (S Poland). We determined the main gradients of species composition using detrended correspondence analysis (DCA), and we identified how DCA scores describe vegetation variability. DCA axes explained 38.5%, 35.4%, 31.4%, and 20.1% of species composition variability. We built machine learning models of DCA scores using multispectral satellite images and airborne laser scanning data as predictors. We obtained good predictive power of models for the first two DCA axes (R2 = 0.393 and 0.443, root mean square errors, RMSE = 0.571 and 0.526) and low power for the third and fourth DCA axes (R2 = 0.216 and 0.064, RMSE = 0.513 and 0.361). These scores allowed us to prepare a vegetation map based on DCA scores, and distinguish meadow‐like from forest‐edge‐like vegetation, and to identify thermophilous and highly productive vegetation patches. Our approach allowed us to account for species composition gradients, which improved remote sensing‐based vegetation surveys. This method may be used for planning future management.
Long‐Term Safety and Efficacy of Pure Laparoscopic Donor Hepatectomy in Pediatric Living Donor Liver Transplantation
Authors: Kim Wan‐Joon , Kim Ki‐Hun , Cho Hwui‐Dong , Namgoong Jung‐Man , Hwang Shin , Park Jeong‐Ik , Lee Sung‐Gyu
Published: October 2020

Laparoscopic living donor hepatectomy for transplantation has been well established over the past decade. This study aimed to assess its safety and feasibility in pediatric living donor liver transplantation (LDLT) by comparing the surgical and long‐term survival outcomes on both the donor and recipient sides between open and laparoscopic groups. The medical records of 100 patients (≤17 years old) who underwent ABO‐compatible LDLT using a left lateral liver graft between May 2008 and June 2016 were analyzed. A total of 31 donors who underwent pure laparoscopic hepatectomy and their corresponding recipients were included in the study; 69 patients who underwent open living donor hepatectomy during the same period were included as a comparison group. To overcome bias from the different distributions of covariables among the patients in the 2 study groups, a 1:1 propensity score matching analysis was performed. The mean follow‐up periods were 92.9 and 92.7 months in the open and laparoscopic groups, respectively. The mean postoperative hospital stay of the donors was significantly shorter in the laparoscopic group (8.1 days) than in the open group (10.6 days; P < 0.001). Overall, the surgical complications in the donors and overall survival rate of recipients did not differ between the groups. Our data suggest that the laparoscopic environment was not associated with long‐term graft survival during pediatric LDLT. In addition, the laparoscopic approach for the donors did not adversely affect the corresponding recipient's outcome. Laparoscopic left lateral sectionectomy for living donors is a safe, feasible, and reproducible procedure for pediatric liver transplantation.
S‐Nitrosoglutathione‐Based Nitric Oxide‐Releasing Nanofibers Exhibit Dual Antimicrobial and Antithrombotic Activity for Biomedical Applications
Authors: Douglass Megan , Hopkins Sean , Pandey Rashmi , Singha Priya , Norman Megan , Handa Hitesh
Published: October 2020

The novel use of nanofibers as a physical barrier between blood and medical devices has allowed for modifiable, innovative surface coatings on devices ordinarily plagued by thrombosis, delayed healing, and chronic infection. In this study, the nitric oxide (NO) donor S‐nitrosoglutathione (GSNO) is blended with the biodegradable polymers polyhydroxybutyrate (PHB) and polylactic acid (PLA) for the fabrication of hemocompatible, antibacterial nanofibers tailored for blood‐contacting applications. Stress/strain behavior of different concentrations of PHB and PLA is recorded to optimize the mechanical properties of the nanofibers. Nanofibers incorporated with different concentrations of GSNO (10, 15, 20 wt%) are evaluated based on their NO‐releasing kinetics. PLA/PHB + 20 wt% GSNO nanofibers display the greatest NO release over 72 h (0.4–1.5 × 10−10 mol mg−1 min−1). NO‐releasing fibers successfully reduce viable adhered bacterial counts by ≈80% after 24 h of exposure to Staphylococcus aureus. NO‐releasing nanofibers exposed to porcine plasma reduce platelet adhesion by 64.6% compared to control nanofibers. The nanofibers are found noncytotoxic (>95% viability) toward NIH/3T3 mouse fibroblasts, and 4′,6‐diamidino‐2‐phenylindole and phalloidin staining shows that fibroblasts cultured on NO‐releasing fibers have improved cellular adhesion and functionality. Therefore, these novel NO‐releasing nanofibers provide a safe antimicrobial and hemocompatible coating for blood‐contacting medical devices.
Scale of Biotelemetry Data Influences Ecological Interpretations of Space and Habitat Use in Yellowtail Snapper
Authors: Novak Ashleigh J. , Becker Sarah L. , Finn John T. , Pollock Clayton G. , Hillis-Starr Zandy , Jordaan Adrian
Published: October 2020

As opposed to passive, broad-scale acoustic telemetry arrays, acoustic positioning systems generate high-resolution animal locations that provide information on long-term, fine-scale movement patterns and habitat preferences. However, limited comparisons have been made between more common broad-scale acoustic data and fine-scale positioning data and it is unknown whether differences exist in ecological inferences gained or lost between using either array configuration over the other. Broad-scale movement and habitat use information was collected for eight Yellowtail Snapper Ocyurus chrysurus tagged within an array of 78 stationary acoustic receivers deployed in Buck Island Reef National Monument, a marine protected area located northeast of St. Croix, U.S. Virgin Islands. An additional 25 receivers were nested within the larger array as a VEMCO Positioning System and were used to assess fine-scale habitat use for five of the eight tagged fish. Broad-scale results inferred from network analysis revealed that all individuals had core use receivers along the shallow shelf break situated west of Buck Island, preferring an area that was coarsely characterized by sand and seagrass benthic habitats. Fine-scale results using Euclidean distance analysis (EDA) suggested fish positions occurred randomly or independent of benthic habitat type. Further exploration of positioning data suggested that there were two contingents or groups of fish displaying unique movement patterns within the fine-scale positioning array. Individuality in space and habitat use was thus masked when using an EDA approach at the study population level, as it was also missed during broad-scale analyses. Discrepancies between broad- and fine-scale habitat inferences suggest that positioning systems are necessary for interpreting habitat use in complex coral reef ecosystems. Nested positioning systems appear to add substantial information that is not obtainable using broad-scale data alone, and caution is necessary in inferring habitat use when only coarse-scale location data are available.
Distinction between arterial and venous occlusion with tissue oxygen pressure in a porcine fascio‐cutaneous flap model
Authors: Lartizien Rodolphe , Besse Sanela , Bettega Paul , Zaccaria Isabelle , Planat‐Chrétien Anne , Berger Michel , Henry Maxime , Coll Jean‐Luc , Bettega Georges
Published: October 2020

Background

In recent years, many devices have been developed to monitor free flaps. The Licox probe, which measures tissue oxygen pressure (PtO2), is one of the available devices. Our aim was to demonstrate that PtO2 could distinguish arterial from venous occlusion in a porcine fascio‐cutaneous flap model.

Materials and methods

Twenty pigs (Sus scrofa domestica, Youna strain, males) were included in this study. The median weight was 87.6 kg (84.6–90.8). Bilateral fascio‐cutaneous flaps based on the superficial inferior epigastric pedicle were harvested from each pig. Thirty‐eight flaps were analyzed in this study and were monitored by a Licox system during vascular occlusion. The flaps were randomized into two groups according to the clamped vessel: the arterial group (n = 19) and the venous group (n = 19). After a stabilization period of almost 40 min, vascular clamping (arterial or venous) was performed using a microvascular clamp for almost 20 min. The curve profiles were compared between arterial and venous occlusion.

Results

The inflection point was reached significantly faster in the arterial group: 11 min (9–16) for arterial clamping and 17 min (13–23) for venous clamping (p = .001). A total of 18/19 (95%) pigs in the arterial group and 13/19 (68%) in the venous group (p = .09) reached a level lower than 10 mmHg. The median duration for pressure to drop below 10 mmHg was 9 min (6–12) for arterial clamping and 10 min (9–16) for venous clamping (p = .06).

Conclusion

We showed that PtO2 decreased faster in cases of arterial occlusion than in cases of venous occlusion in a pig model. Based on this observation, it may be possible to distinguish arterial from venous occlusion.
Effect of mating on mRNA and protein expression of beta nerve growth factor and its receptor, TrKA, in the oviduct of llama (Lama glama)
Authors: Sari Luciana M. , Zampini Renato , Argañaraz Martin E. , Ratto Marcelo H. , Apichela Silvana A.
Published: October 2020

Copulation produces different stimuli in the female reproductive tract in camelids, which lead to ovulation. Expression of β‐nerve growth factor (β‐NGF) and its specific receptor, tropomyosin receptor kinase A (TrKA), was studied comparing the oviductal microenvironment of mated and nonmated llamas. β‐NGF and TrKA were expressed in the llama ampulla, isthmus, and utero‐tubal‐junction (UTJ), and they were mainly colocalized in the apical region of the oviductal mucosa. A TrKA immunosignal was also found in muscle cells and blood vessels, with the highest mark in UTJ muscle cells of copulated females. Both β‐NGF and TrKA transcripts were expressed in the three oviductal segments. Relative TrKA abundance did not differ between mated and nonmated females, but relative β‐NGF abundance was higher in the UTJ of copulated females (p < .05). β‐NGF might not be secreted into the oviductal fluid (OF) since the protein was not found in the OF of mated or nonmated females. Therefore, it can be concluded that the llama oviduct expresses the β‐NGF/TrKA system and that an increase in β‐NGF gene expression in the UTJ 24 h after copulation along with an increase in TrKA protein expression may indicate an important role in the gamete transport and fertilization process in llamas.
Reactor and Product Optimization via Raman Fiber Optics Monitoring: Application to Polymer‐Based Proppants
Authors: Rey Candela , Zuviría Gonzalo , Rivelli Sofía , Giannetti Rocío , Tomba J. Pablo , Carella José M.
Published: October 2020

A setup to characterize polymerization kinetics of polymer‐based proppants produced in an industrial batch reactor by suspension polymerization is presented. A microscale reactor is designed to mimic temperature and pressure conditions of the industrial counterpart. Raman spectroscopy is used to follow the consumption of vinyl bonds of the styrene monomer and the crosslinker via disappearance of the peak at 1632 cm‐1. Raman data from the microscale reactor are remotely obtained via a fiber optics system. Reaction progress by any generic formulation can be safely followed up to conversions of 90%, well beyond the gel point. Reaction rates are used to define feasible temperature–time profiles for the industrial reactor. In parallel, bulk and suspension polymerizations are carried out under those temperature–time profiles in a 3 L laboratory reactor to produce proppants formulations with the geometry required to perform product characterization, mainly focused on the thermal and mechanical response of the polymer particles. Overall, the whole setup allows optimization of proppant formulations and the cost of their processes of production.
The disadvantage of the Cμ‐rule when customers are strategic
Authors: Haviv Moshe , Oz Binyamin
Published: October 2020

The question of priorities naturally arises when optimizing service systems with heterogeneous customers. If heterogeneity is with respect to time sensitivity and social welfare is of interest, it is well known that the Cμ‐rule is optimal in the sense that customers with high time sensitivity should be prioritized. This, for example, justifies prioritizing more acute patients in public health systems. Using a standard queueing model with strategic customers, we show that, as expected, if admission is centrally controlled, the Cμ‐rule remains optimal. However, if admission cannot be controlled, for example, in some public healthcare systems, the Cμ‐rule leads to an unusual equilibrium joining behavior. We show that this behavior may result in an inferior social welfare, compared to service disciplines that do not prioritize based on individual time sensitivity level, for example, first‐come first‐served (FCFS). In particular, the equilibrium strategy under the Cμ‐rule is not threshold‐based and all customers join with some (type‐specific) positive probability. The suboptimality of the Cμ‐rule is then demonstrated in a case where the potential arrival rate is high enough such that all the joining probabilities are also less than one. This implies that the resulting social welfare is zero while it is guaranteed to be positive under FCFS.
Minimizing convex quadratics with variable precision conjugate gradients
Authors: Gratton Serge , Simon Ehouarn , Titley‐Peloquin David , Toint Philippe L.
Published: October 2020

We investigate the method of conjugate gradients, exploiting inaccurate matrix‐vector products, for the solution of convex quadratic optimization problems. Theoretical performance bounds are derived, and the necessary quantities occurring in the theoretical bounds estimated, leading to a practical algorithm. Numerical experiments suggest that this approach has significant potential, including in the steadily more important context of multiprecision computations.
Assessment and analysis of patient safety competency of Chinese nurses with associate degrees: A cross‐sectional study
Authors: Yan Lupei , Yao Lili , Li Yuerong , Chen Hao
Published: October 2020

Aim

To analyse the patient safety competency (PSC) of Chinese nurses with associate degrees (ADNs) and explore factors.

Design

A cross‐sectional study.

Methods

A convenience sample of 451 ADNs working in 18 hospitals located in Chongqing city of China was investigated using the Patient Safety Competency Nurse Evaluation Scale (PSCNES). Descriptive and inferential statistics were used to analyse the data.

Results

ADNs had a moderate level of PSC. In terms of the six dimensions of PSC, ADNs performed well in clinical practice and safety risk management, while they performed poorly in patient‐centred care and patient safety culture. Statistically significant differences were reported in two items. Firstly, ADNs who have participated in patient safety training had a higher level in all dimensions of PSC than those who have not participated in related training. Secondly, ADNs without professional titles had a higher level of patient safety culture than those with professional titles.
Raising awareness of suicide prevention during the COVID‐19 pandemic
Authors: Que Jianyu , Yuan Kai , Gong Yimiao , Meng Shiqiu , Bao Yanping , Lu Lin
Published: October 2020

Suicide is one of the top 20 leading causes of death worldwide. With the rapid spreading of coronavirus disease 2019 (COVID‐19) crisis around the world, suicide cases induced by the COVID‐19 pandemic have been reported in many countries. Individuals with suspected and confirmed COVID‐19 infection, frontline healthcare workers, bereaved families, elders, children, and adolescents are vulnerable populations who might be at elevated suicide risk. In this micro‐review, a systematic search through PubMed was performed for a comprehensive investigation of suicide risk factors during the pandemic. On this basis, we put forward considerations and advice for preventing pandemic related suicide, including staying socially connected through online platform or apps during period of quarantine, reducing unemployment, dispelling rumors and misinformation in time, and maintaining evidenced‐based management of psychiatric symptoms. More importantly, early detection and timely intervention of individuals with psychiatric disorders and suicide behaviors will be effective to reduce the number of suicides, with specific measurements of using validated scales to perform regular suicide risk screening, improving the availability of mental health services, and providing appropriate and evidence‐based interventions for individuals in demand. Policy makers, psychiatrists, psychologists, and other healthcare professionals need to collaborate to control the possible suicide events during the COVID‐19 pandemic and future possible crisis.
Preparation, characterization and properties of biodegradable poly(butylene adipate‐co‐butylene terephthalate)/thermoplastic poly(propylene carbonate) polyurethane blend films
Authors: Zhang Ye , Jia Shiling , Pan Hongwei , Wang Lijuan , Zhang Huiliang , Yang Huili , Dong Lisong
Published: October 2020

Poly(butylene adipate‐co‐terephthalate) (PBAT)/thermoplastic poly(propylene carbonate) polyurethane (PPCU)/ADR blend films were obtained by melt blending and blowing films technique. The rheological behavior, thermal properties, mechanical properties, barrier properties, water vapor permeability (WVP), wettability performances, optical properties, and biodegradability properties were investigated. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) indicated that PBAT and PPCU had good miscibility. The addition of PPCU could reduce the crystallization process. All blend films exhibited good mechanical properties with high tensile strength of 42.1 to 66.6 MPa and elongation at break of 629% to 968% in the machine direction (MD) and tensile strength of 33.2 to 46.4 MPa and elongation at break of 1080% to 1665% in the transverse direction (TD). The thermal stability of PBAT/PPCU/ADR blend films was decreased when PPCU was added, however the processing and use of blend films were not affected. From barrier properties and WVP analysis, all PBAT/PPCU/ADR blend films showed good water vapor barrier properties and gas barrier performance. Surfaces of PBAT/PPCU/ADR blend films were hydrophobic with contact angle of 94.3° to 102.6°. All PBAT/PPCU/ADR blend films had high transparency. Biodegradability results showed that PPCU content could affect biodegradability of the films. This study indicates that PBAT/PPCU/ADR blend films as biodegradable packaging materials have great potential for application in fresh fruit and vegetable packaging, cosmetics and other industries in the future.
Polypropylene/wood powder/ethylene propylene diene monomer rubber‐maleic anhydride composites: Effect of PP melt flow index on the thermal, mechanical, thermomechanical, water absorption, and morphological parameters
Authors: da Silva Barbosa Ferreira Eduardo , Luna Carlos Bruno Barreto , Araújo Edcleide Maria , Siqueira Danilo Diniz , Wellen Renate Maria Ramos
Published: October 2020

Environmental damage promoted trough post‐consumer waste from the wood industry has worried the society, while its inadequate disposal has raised concerns of the scientific community. Environmentally and economically effective alternative is reusing this residue to produce smart composites. Therefore, this work aimed to investigate the performance of polypropylene (PP)/Jatobá Wood Powder (WP) composites compatibilized with ethylene propylene diene monomer rubber‐maleic anhydride (EPDM‐MA). The effect of distinct melt flow index (MFI) (PP H103 and PP H503) was also investigated. The composites were characterized using differential scanning calorimetry, thermogravimetry, mechanical properties (tensile, flexural, impact, and Shore D hardness), heat deflection temperature, Vicat softening temperature, water absorption and scanning electron microscopy (SEM). Addition of EPDM‐MA, increased impact strength. The best performance was observed for the composition with 10% EPDM‐MA and PP with lower MFI (PP H503). EPDM‐MA also decreased the water absorption for both PP, most due to the chemical interactions among composite phases. SEM images suggest encapsulation of wood particles by EPDM‐MA, promoting better composites performance. Reported results are valuable for the recycling industry, as well as are economically and environmentally promising.
Synthesis, characterization and nanoparticle formation of polyarylene poly(amic acid)s and polyimides containing fluorescent dye moieties
Authors: Budy Stephen M , V Rose Joseph , Gibson Corinne , Son David Y
Published: October 2020

New naphthalene‐ and perylene‐containing polyarylene poly(amic acid)s and polyimides were synthesized from a new phenylated phenylenediamine. A small‐molecule model compound was also synthesized with naphthalene end‐groups. The new compounds were characterized, and the structures were confirmed using 1H NMR and attenuated total reflectance Fourier transform infrared spectroscopy. Thermal characterization was conducted using thermogravimetric analysis and differential scanning calorimetry. Onset of thermal degradation temperatures for the naphthalene and perylene polyimides were 561 and 545 °C, and char yields at 1000 °C were 61 and 59% (under nitrogen), respectively. The glass transition temperatures were 381 and 396 °C, respectively. Molecular weights determined using gel permeation chromatography were Mw = 35 000 and 24 000 g mol−1, respectively. The absorption maxima were at 387 and 427/458/491/527 nm, respectively, while the fluorescence emission maxima were at 498 and 541/582 nm, respectively. Nanoparticles were prepared from these new fluorescent dye‐containing polyarylene polyimides with sizes of 102/397 and 177 nm, respectively, as determined using dynamic light scattering. © 2020 Society of Industrial Chemistry
Observations of air–sea heat fluxes in the southwestern Atlantic under high‐frequency ocean and atmospheric perturbations
Authors: Santini M. F. , Souza R. B. , Pezzi L. P. , Swart S.
Published: October 2020

Turbulent air–sea heat fluxes were computed from in situ high‐frequency micrometeorological data during two research cruises performed in the southwestern Atlantic Ocean (SWAO) occurring in June 2012 and October 2014. Two different and dynamical areas were covered by the cruises: the Brazil‐Malvinas Confluence (BMC) and the Southern Brazilian Continental Shelf (SBCS). The eddy covariance (EC) method was used to estimate the air–sea sensible‐ and latent‐heat fluxes. This article compares these novel high‐frequency estimates of heat fluxes with bulk parametrizations made at the same location and time from independent measurements taken on board the ships. When comparing the EC and bulk‐estimated time series of sensible‐heat fluxes, we found a good agreement both in their magnitude and variability, with small bias (generally <20 W·m−2) between the datasets from the two study areas in the SWAO. However, the EC and bulk latent‐heat flux comparisons show large biases ranging from 75 W·m−2 to 100 W·m−2 in the SBCS and BMC, respectively. These biases were always associated with short‐term, high‐frequency environmental perturbations occurring either in the atmosphere or in the ocean with the majority related to strong wind burst events and large air–sea temperature gradients. The short period changes in atmospheric conditions were mostly related to the passage of transient synoptic systems over the two study areas. The large air–sea temperature gradients were mostly linked to the surface characteristics of the BMC and SBCS regions, where sharp oceanographic fronts are located. Our results are able to contribute to improving weather and climate simulations of the mid‐ to high latitudes of South America, a region largely influenced by the sea‐surface temperature patterns of the SWAO in combination with the frequent propagation of transient atmospheric systems.
Covid‐19 and kidney injury: Pathophysiology and molecular mechanisms
Authors: Ahmadian Elham , Hosseiniyan Khatibi Seyed Mahdi , Razi Soofiyani Saiedeh , Abediazar Sima , Shoja Mohammadali M. , Ardalan Mohammadreza , Zununi Vahed Sepideh
Published: October 2020

The novel coronavirus (SARS‐CoV‐2) has turned into a life‐threatening pandemic disease (Covid‐19). About 5% of patients with Covid‐19 have severe symptoms including septic shock, acute respiratory distress syndrome, and the failure of several organs, while most of them have mild symptoms. Frequently, the kidneys are involved through direct or indirect mechanisms. Kidney involvement mainly manifests itself as proteinuria and acute kidney injury (AKI). The SARS‐CoV‐2‐induced kidney damage is expected to be multifactorial; directly it can infect the kidney podocytes and proximal tubular cells and based on an angiotensin‐converting enzyme 2 (ACE2) pathway it can lead to acute tubular necrosis, protein leakage in Bowman's capsule, collapsing glomerulopathy and mitochondrial impairment. The SARS‐CoV‐2‐driven dysregulation of the immune responses including cytokine storm, macrophage activation syndrome, and lymphopenia can be other causes of the AKI. Organ interactions, endothelial dysfunction, hypercoagulability, rhabdomyolysis, and sepsis are other potential mechanisms of AKI. Moreover, lower oxygen delivery to kidney may cause an ischaemic injury. Understanding the fundamental molecular pathways and pathophysiology of kidney injury and AKI in Covid‐19 is necessary to develop management strategies and design effective therapies.
Distributed fault estimation for linear systems with actuator faults
Authors: Han Weixin , Trentelman Harry L. , Wang Zhenhua , Shen Yi
Published: October 2020

This article investigates the problem of designing a distributed fault estimation observer (DFEO) for a given linear time invariant observed system with disturbances. The DFEO consists of a network of local fault estimation observers. The local observers at the network nodes are physically distributed and hence each of them has access to only part of the output of the observed system. Each local fault estimation observer communicates with its neighbors as prescribed by the given network graph. Both full order and reduced order DFEO's are presented in this article. A systematic design procedure for DFEO gains is addressed, enabling the estimation error dynamics to be robust against the effects of the external process disturbance and the derivative of the fault. The numerical design of our DFEO is amounts to solving an optimization problem with constraints of a bank of linear matrix inequalities. Finally, we illustrate the effectiveness of the proposed distributed fault estimation approach by means of a number of simulation results.
Robust trajectory tracking control of a marine surface vessel using asymmetric error constraints and output feedback
Authors: Chen Guangjun , Tian Xuehong , Liu Haitao
Published: October 2020

This article investigates the problem of robust trajectory tracking for a marine surface vessel in the presence of asymmetrical error time‐varying constraints and output feedback. To deal with system uncertainties, adaptive neural networks (NNs) are used to approximate unknown dynamics model parameters and external disturbances. To obtain unmeasured velocities, a predictive observer based on output feedback is developed to estimate unknown velocities. A tan‐type asymmetric barrier Lyapunov function is used to deal with asymmetric error time‐varying constraints. The high‐frequency robust adaptive law is used to compensate for parameter estimation errors. The kinematic controller is designed based on the barrier Lyapunov function method, and the kinetics controller is designed base on an observer, an adaptive NN and a robust high‐frequency control. All signals of the closed‐loop systems are proved to be semiglobally uniformly and ultimately bounded via Lyapunov analysis, and the asymmetrical error constraints are not violated. Simulations are performed, and synthetic comparison is used to verify the feasibility and robustness of the proposed control law.
Quantitative analysis of calcium and fluorine by high‐sensitivity low‐energy ion scattering: Calcium fluoride
Authors: Průša Stanislav , Bábík Pavel , Šikola Tomáš , Brongersma Hidde H.
Published: October 2020

Low‐energy ion scattering (LEIS) probes the atomic composition of the outer surface. Well‐defined reference samples are used for the quantitation. For elements like fluorine and calcium, it is not easy to find suitable, clean, and homogeneous references, since fluorine is a gas and calcium is a very reactive metal. In contrast to surface analytic techniques such as XPS, the extreme surface sensitivity of LEIS makes it difficult to use stable compounds like CaF2 as reference, since these compounds are not homogeneous at the atomic scale. With LEIS, CaF2 is not expected to show an atomic ratio F/Ca = 2.0. Thus, before CaF2 can be used as reference, its atomic surface concentrations have to be determined. Here, 3‐keV He+ scattering by a LiF(001) single crystal, an evaporated layer of Ca, and a Cu foil are used as basic references. High‐purity CaF2 is available in two forms: a single crystal and a powder. For a practical reference, powders are preferred, since if bulk impurities segregate to the surface, they will be dispersed over a large surface area. It is found that both CaF2 (111) and powder have similar F/Ca atomic ratios. This confirms the F termination for both samples. For the powder, the F and Ca signals are reduced by 0.77 ± 0.03 in comparison with those for the single crystal. The atomic sensitivity factors and relative sensitivity factors have been determined for F, Ca, and Cu.
DBU: A Reaction Product Component
Authors: Muzart Jacques
Published: October 2020

DBU (1,8‐diazabicyclo[5.4.0]undec‐7‐ene) is traditionally considered to be a non‐nucleophilic base. Nevertheless, DBU possesses nucleophilic properties which mediate organic reactions and may lead to the formation of compounds containing the DBU scaffold. Participation of water to the processes affords there‐component products. The review covers the reactions leading to DBU derivatives showing that the interest of this sterically hindered amidine is not limited to its basic role. Proposed mechanisms are described with, in some cases, personal comments.
Facile Synthesis of Novel Pyrano‐Pyrido‐Carbazole Scaffolds Using Magnetic Fe3O4 Nanoparticles as a Heterogeneous Green and Reusable Catalyst
Authors: Parmar Sarita , Sharma Vikash , Jain Shubha , Verma Divya
Published: October 2020

We reported a novel series of pyrano‐pyrido‐carbazol derivatives (PPCDs) 6(a‐o), synthesized via the reaction of 4‐hydroxypyridocarbazolone (3), aryl/heteroaryl aldehyde (4), and malononitrile (5), in water using Fe3O4 magnetite nanoparticles (Fe3O4 MNPs) as a heterogeneous novel catalyst at room temperature just in 60 mins under ultrasound. For this propose, Fe3O4 MNPs with particle size 23.4±0.9 nm was successfully synthesized via a one‐step novel coprecipitation method in aqueous medium by the use of a new alkaline agent i. e. 2 ‐(ethylamino) ethanol and systematically characterized using field emission scanning electron microscopy (FESEM), high‐resolution transmission electron microscopy (HRTEM), energy dispersive analysis of X‐ray (EDAX), X‐ray diffraction (XRD), x‐ray photoelectron spectroscopy (XPS) and Fourier transformed infrared (FTIR). Fe3O4 MNPs show remarkably dramatic dispersion stability as evident from zetapotential (ζ) value of −38.9 mV and hydrodynamic diameter (HD) of 238 nm and excellent specific surface area of 185 m2 /g. Additionally, Fe3O4 MNPs was easily separated after completion of the reaction, from the reaction mixture using the external magnet, and can be reused seven times without any considerable loss of its activity. The use of ultrasound made homogeneous dispersion of MNPs in water which accelerated the rate of reaction for the synthesis of PPCDs. This protocol has notable advantages like the synthesis of novel PPCDs with high yield in short reaction time, inexpensive catalyst, eco‐safe, and also favour green chemistry protocol.
High Open‐Circuit Voltage in Full‐Inorganic Sb2S3 Solar Cell via Modified Zn‐Doped TiO2 Electron Transport Layer
Authors: Ishaq Muhammad , Chen Shuo , Farooq Umar , Azam Muhammad , Deng Hui , Su Zheng-Hua , Zheng Zhuang-Hao , Fan Ping , Song Hai-Sheng , Liang Guang-Xing
Published: October 2020

Antimony sulfide (Sb2S3) is emerging as a popular photovoltaic candidate for thin‐film solar cells due to its large absorption coefficient, suitable bandgap, nontoxic, and earth‐abundant nature. The performance of thermally evaporated Sb2S3 devices is severely restricted by interfacial recombination leading to high open‐circuit voltage (VOC) losses. CdS as electron transport layer (ETL) has overcome this problem, but triggered lower JSC issues due to parasitic absorption loss conceding to its smaller bandgap. Herein, a spray pyrolysis method is adopted for the deposition of a uniform and compact Zn‐doped TiO2 film with tuned energy levels to facilitate charge extraction and transport. The solar cell fabricated with a modified TiO2 ETL holds superior interface quality, high build‐in potential, and suppressed recombination losses, therefore pronouncedly improves the VOC. As a result, the efficiency of the device is boosted from 4.41% to 5.16%, a record VOC of 702 mV for Cd‐free full‐inorganic Sb2S3 solar cell is achieved. These findings are expected to be implemented in other Sb‐chalcogenide solar cells to further enhance the device performance.
An evaluation framework for privacy‐preserving solutions applicable for blockchain‐based internet‐of‐things platforms
Authors: Firoozjaei Mahdi Daghmehchi , Lu Rongxing , Ghorbani Ali A.
Published: October 2020

Blockchain‐based applications provide many promising opportunities to overcome the challenges associated with the Internet of Things (IoT) ecosystems (eg, centralized architecture, data integrity, and reliability). In particular, blockchain technology offers many desirable features for IoT infrastructures, such as decentralization, trustworthiness, trackability, and immutability. However, while logging all transactions in a distributed blockchain ledger provides transparency, it also makes it possible to compromise user's privacy, thus posing a grand challenge to IoT architects and implementers. Over the past years, a set of solutions have been proposed for various scenarios, to address these privacy issues. In this paper, we survey these solutions, classify, and analyze their advantages and disadvantages. We also introduce an evaluation framework to evaluate the quality of the privacy‐preserving based on an adjustable weighting scheme. Finally, we rate the analyzed solutions based on their privacy ranks, and hope our evaluation can shed light on the future design of privacy‐preserving solutions applicable for blockchain‐based IoT platforms.
Minimizing Voltage Losses in Perovskite Solar Cells
Authors: Chen Peng , Bai Yang , Wang Lianzhou
Published: October 2020

Organic–inorganic metal halide perovskite solar cells (PSCs) have achieved an unprecedented increase in power conversion efficiency (PCE) from 3.8% to 25.2% in the past decade. Given that the open‐circuit voltage (Voc) of PSCs is well below its theoretical limit due to the trap‐mediated charge recombination and energy band alignment mismatch, there is still considerable scope to further increase the PCE by minimizing Voc losses. Herein, a fundamental understanding on the origins of voltage losses in PSCs is summarized. Then, the strategies for mitigating the voltage losses of PSCs are critically reviewed, including crystal growth control, grain‐boundary defect passivation, interfacial defect passivation, and band alignment optimization. Finally, the current challenges are discussed and the future directions are outlined to further boost the Voc of PSCs toward their radiative limit.
Lateral stiffness and preliminary design methodology of twisted diagrid tube structures
Authors: Song Sirui , Zhang Chonghou
Published: October 2020

Twisted forms have been widely employed in high‐rise buildings in recent years. The diagrid structural system is particularly suitable for twisted buildings because of its large lateral stiffness and unique architectural esthetics, but little research on twisted diagrid tube structures is currently available. This paper studies the influence of diagonal angle, twist rate, aspect ratio, corner column, and plan form on the lateral stiffness of twisted diagrids, and the optimal diagonal angle range is determined. Considering the stiffness and strength criteria, the design methodology of diagonal sizes of twisted diagrids is proposed, and the methodology is validated by finite element analysis. In addition, this paper presents a novel configuration of twisted diagrid, that is, the twisted diagrid with asymmetric diagonal angles. The influence of the left‐ and right‐inclined diagonal angle on the lateral stiffness of twisted diagrids is investigated. It is found that twisted diagrid structure with asymmetric diagonal angles exhibits larger lateral stiffness than the symmetric case. The results in this paper are useful for engineers to determine the configuration and diagonal sizes of the twisted diagrid tube structures.
Seismic analysis of a reinforced concrete building isolated by high damping rubber bearings using deformation history integral type model
Authors: Hu Xiaorong , Zhou Zhiguang
Published: October 2020

The base‐isolation system is a very effective technology for earthquake resistance. Nevertheless, it is adverse to the horizontal displacement control of isolation layer and less efficient in reducing the seismic response of the superstructure on a soft soil. The high damping rubber bearings can provide large hysteretic damping and show hardening effect at high shear strains. To explore the applicability of high damping rubber bearings (HDRBs) and the effect of their characteristics on the seismic responses of the structures on soft soils, a six‐story reinforced concrete (RC) building isolated by HDRBs on a soft soil is modeled in SAP2000. By applying deformation history integral type model (DHI model) which can accurately simulate the characteristics of HDRBs and traditional Bouc–Wen model which ignores the hardening effect and high energy dissipation capacity of HDRBs at large shear strains to the bearings separately, seismic responses considering and neglecting the hardening effect and high energy dissipation capacity of HDRBs at large shear strains are investigated. The comparison of the two models shows that the characteristics of HDRBs can effectively reduce the displacement of the isolation layer under extremely strong earthquakes and are conducive to the safety of superstructure under limited earthquake intensities.
Electrochemical Phosphorylation of Organic Molecules
Authors: Sbei Najoua , Martins Guilherme M. , Shirinfar Bahareh , Ahmed Nisar
Published: October 2020

Organophosphorus chemistry is a broad field with multi‐dimensional applications in research area of organic, biology, drug design and agrochemicals. Conventional methods have been adopted extensively to access phosphorylated compounds that rely on the use of toxic, moisture sensitive phosphorylating agents and occur in the presence of oxidants, catalysts, as well as high temperatures and harsh conditions are required for complete transformations. However, recent progress has been made for phosphorylation reactions using electricity to introduce green and sustainable synthetic procedures. These reactions can be performed at mild conditions and proceed with excellent atom economy. Herein, we targeted electrochemical phosphorylation reactions with generation of new bonds such as C(sp3) −P, C(sp2) −P, O−P, N−P, S−P and Se−P. This review is aimed to offer an overview of recent developments in the synthetic methodology to easy access of organophosphorus compounds using electrochemistry.
A Supersymmetric Hierarchical Model for Weakly Disordered 3d Semimetals
Authors: Antinucci Giovanni , Fresta Luca , Porta Marcello
Published: October 2020

In this paper, we study a hierarchical supersymmetric model for a class of gapless, three-dimensional, weakly disordered quantum systems, displaying pointlike Fermi surface and conical intersections of the energy bands in the absence of disorder. We use rigorous renormalization group methods and supersymmetry to compute the correlation functions of the system. We prove algebraic decay of the two-point correlation function, compatible with delocalization. A main technical ingredient is the multiscale analysis of massless bosonic Gaussian integrations with purely imaginary covariances, performed via iterative stationary phase expansions.
Semigroup-theoretic approach to diffusion in thin layers separated by semi-permeable membranes
Authors: Bobrowski Adam
Published: October 2020

Using techniques of the theory of semigroups of linear operators, we study the question of approximating solutions to equations governing diffusion in thin layers separated by a semi-permeable membrane. We show that as thickness of the layers converges to 0, the solutions, which by nature are functions of 3 variables, gradually lose dependence on the vertical variable and thus may be regarded as functions of 2 variables. The limit equation describes diffusion on the lower and upper sides of a two-dimensional surface (the membrane) with jumps from one side to the other. The latter possibility is expressed as an additional term in the generator of the limit semigroup, and this term is built from permeability coefficients of the membrane featuring in the transmission conditions of the approximating equations (i.e., in the description of the domains of the generators of the approximating semigroups). We prove this convergence result in the spaces of square integrable and continuous functions, and study the way the choice of transmission conditions influences the limit.