bluuebunny/crossref_metadata_2025 huggingface dataset:
At the same time or one after the other? – Exploring reaction paths of nucleophilic substitution reactions using historic insights and experiments
Authors: Pölloth Benjamin , Häfner Malín , Schwarzer Stefan
Published: January 2022

Viele Lernende nehmen die organische Chemie (OC) als unstrukturiertes und unübersichtliches Fachgebiet wahr. Reaktionsmechanismen werden dabei häufig nicht als Orientierungshilfen, sondern vielmehr als zusätzliche Herausforderungen betrachtet. Zu Beginn des 20. Jahrhunderts hatte die OC als Fachwissenschaft mit vergleichbaren Problemen zu kämpfen. Einen Wendepunkt stellte hier die systematische Anwendung physikalischer Prinzipien auf organische Reaktionen durch die Forschenden um Ingold dar. Kinetische Untersuchungen legten beispielsweise nahe, dass in nukleophilen Substitutionsreaktionen die Abspaltung der Abgangsgruppe und der Angriff des Nukleophiles entweder gleichzeitig oder nacheinander stattfinden können. In der vorliegenden Arbeit werden diese historischen Erkenntnisse durch einfache, schulgeeignete Experimente für den Unterricht zugänglich gemacht. Ein fiktives Audiotagebuch von Hilda Ingold wird als history lift vorgeschlagen, um den Schüler:innen die grundlegende Erkenntnis zu ermöglichen, dass für einen Reaktionstyp prinzipiell verschiedene Reaktionswege denkbar sind.
Efficacy and safety of dronedarone versus placebo in patients with atrial fibrillation stratified according to renal function: Post hoc analyses of the EURIDIS‐ADONIS trials
Authors: Thind Munveer , Zareba Wojciech , Atar Dan , Crijns Harry J. G. M. , Zhu Jun , Pak Hui‐Nam , Reiffel James , Ludwigs Ulf , Wieloch Mattias , Stewart John , Kowey Peter
Published: January 2022

Background

The use of antiarrhythmic drugs (AADs) in patients with chronic kidney disease (CKD) is complex because impaired renal clearance can cause increased drug levels, and risk of intolerance or adverse events. Due to the propensity for CKD to occur alongside atrial fibrillation/atrial flutter (AF/AFL), it is essential that AAD safety and efficacy are assessed for patients with CKD.

Hypothesis

Dronedarone, an approved AAD, may present a suitable therapeutic option for patients with AF/AFL and concomitant CKD.

Methods

EURIDIS‐ADONIS (EURIDIS, NCT00259428; ADONIS, NCT00259376) were identically designed, multicenter, double‐blind, parallel‐group trials investigating AF/AFL control with dronedarone 400 mg twice daily versus placebo (randomized 2:1). In this post hoc analysis, the primary endpoint was time to first AF/AFL. Patients were stratified according to renal function using the CKD‐Epidemiology Collaboration equation and divided into estimated glomerular filtration rate (eGFR) subgroups of 30–44, 45–59, 60–89, and ≥90 ml/min. Time‐to‐events between treatment groups were compared using log‐rank testing and Cox regression.

Results

At baseline, most (86%) patients demonstrated a mild or mild‐to‐moderate eGFR decrease. Median time to first AF/AFL recurrence was significantly longer with dronedarone versus placebo for all eGFR subgroups except the 30 to 44 ml/min group, where the trend was similar but statistical power may have been limited by the small population. eGFR stratification had no significant effect on serious adverse events, deaths, or treatment discontinuations.

Conclusions

This analysis suggests that dronedarone could be an effective therapeutic option for AF with an acceptable safety profile in patients with impaired renal function.
Single‐center experience of ultra‐high‐density mapping guided catheter ablation of focal atrial tachycardia
Authors: Kellnar Antonia , Fichtner Stephanie , Mehr Michael , Czermak Thomas , Sinner Moritz F. , Lackermair Korbinian , Estner Heidi L.
Published: January 2022

Introduction

Catheter ablation is the treatment of choice for recurrent focal atrial tachycardia (FAT) as medical therapy is limited. Routinely, a three‐dimensional mapping system is used. Whether or not optimized signal detection does improve ablation success rates has not yet been investigated. This retrospective cohort study compared ablation procedures using an ultra‐high‐density mapping system (UHDM, Rhythmia, Boston Scientific) with improved signal detection and automatic annotation with procedures using a conventional electroanatomic mapping system (CEAM, Biosense Webster, CARTO).

Methods

All patients undergoing ablation for FAT using UHDM or CEAM from April 2015 to August 2018 were included. Endpoints comprised procedural parameters, acute success as well as freedom from arrhythmia 12 months after ablation.

Results

A total of 70 patients underwent ablation (48 with UHDM, 22 with CEAM). No significant differences were noted for parameters like procedural and radiation duration, area dose, and RF applications. Acute success was significantly higher in the UHDM cohort (89.6% vs. 68.2%, p = .03). Nevertheless, arrhythmia freedom 12 months after ablation was almost identical (56.8% vs. 60%, p = .87), as more patients with acute success of ablation presented with a relapse during follow‐up (35.0 vs. 7.7%, p = .05).

Conclusion

Acute success rate of FAT ablation might be improved by UHDM, without an adverse effect on procedural parameters. Nevertheless, further research is needed to understand the underlying mechanism for increased recurrence rates after acute successful ablation.
Synthesis and Evaluation of a Class of Compounds Inhibiting the Growth of Stromal Antigen 2 (STAG2)‐Mutant Ewing Sarcoma Cells
Authors: Zhang Nenggang , Lin Keng‐Fu , Yang Christian , Peruski Scott , Pati Debananda , Gilbertson Scott R.
Published: January 2022

STAG2 (SA2) is a critical component of the cohesin complex that regulates gene expression and the separation of sister chromatids in cells. Mutations in STAG2 have been identified in over thirty different types of cancers including myeloid leukaemia, non‐small cell lung, bladder and Ewing sarcoma. Selectively inhibiting cancer cells lacking of STAG2 is an attractive approach for the cancer therapy. Here we report that a small molecule, StagX1, identified through a high‐throughput screening, inhibits the growth of Ewing sarcoma cells possessing mutant STAG2. A new synthetic route to the StagX1 scaffold and new versions of the molecule along with their activity in a cell viability assay are reported.
Whole‐blood cytokine secretion assay as a high‐throughput alternative for assessing the cell‐mediated immunity profile after two doses of an adjuvanted SARS‐CoV‐2 recombinant protein vaccine candidate
Authors: De Rosa Stephen C , Cohen Kristen W , Bonaparte Matthew , Fu Bo , Garg Sanjay , Gerard Catherine , Goepfert Paul A , Huang Ying , Larocque Daniel , McElrath M. Juliana , Morris Daryl , Van der Most Robbert , de Bruyn Guy , Pagnon Anke
Published: January 2022

Objectives

We previously described the Phase I‐II evaluation of SARS‐CoV‐2 recombinant protein candidate vaccine, CoV2‐PreS‐dTM, with AF03‐ or AS03‐adjuvant systems (ClinicalTrials.gov, NCT04537208). Here, we further characterise the cellular immunogenicity profile of this vaccine candidate using a whole‐blood secretion assay in parallel to intracellular cytokine staining (ICS) of cryopreserved peripheral blood mononuclear cells (PBMCs).

Methods

A randomly allocated subset of 90 healthy, SARS‐CoV‐2‐seronegative adults aged ≥ 18 years who had received (random allocation) one or two separate injections (on study day [D]1 and D22) of saline placebo or CoV2‐PreS‐dTM formulated with AS03 or AF03 were included. Cytokine secretion was assessed using a TruCulture® whole‐blood stimulation system in combination with multiplex bead array, and intracellular cytokine profiles were evaluated on thawed PBMCs following ex vivo stimulation with recombinant S protein at pre‐vaccination (D1), post‐dose 1 (D22) and post‐dose 2 (D36).

Results

Both methods detected similar vaccine‐induced responses after the first and second doses. We observed a Th1 bias (Th1/Th2 ratio > 1.0) for most treatment groups when analysed in whole blood, mainly characterised by increased IFN‐γ, IL‐2 and TNF‐α secretion. Among participants aged ≥ 50 years, the Th1/Th2 ratio was higher for those who received vaccine candidate with AS03 versus AF03 adjuvant. ICS revealed that this higher Th1/Th2 ratio resulted from higher levels of IFN‐γ expression and that the vaccine induced polyfunctional CD4+ T cells.

Conclusions

The whole‐blood cytokine secretion assay is a high‐throughput alternative for assessing the quantity and character of vaccine‐induced cellular responses.
An efficient virtualized network function deployment scheme for service function chain using deep Q‐network
Authors: Wu Wei‐Cheng , Kao Shang‐Juh , Chang Fu‐Min
Published: January 2022

Virtualized network functions (VNFs) are virtualized network services running on the network functions virtualization infrastructure in order to replace physical hardware. Integrating with software defined networking and network functions virtualization, internet service providers (ISPs) can chain VNFs together, called service function chain (SFC), to provide various network service demands with virtual links. Many studies have proposed for the VNFs deployment under different objectives, for example, energy, delay, quality of service (QoS), and quality of experience (QoE). From the aspects of both ISPs and customers, both energy consumption and QoE are the primary concerns for the purpose of operating expense reduction and users' satisfaction. This paper proposes a QoS/QoE/energy‐aware deep Q‐network (DQN)‐based scheme, called DQN‐QQE for VNFs deployment under the consideration of both energy consumption and QoE requirement with QoS constraints. The reward of the proposed scheme is formulated by the Weber‐Fechner law and the exponential interdependency of QoE and QoS (IQX) hypothesis. Afterwards, we compared the proposed DQN‐QQE to the QoS/QoE‐aware approach DQN‐Q2‐SFC, brute force, and randomness in terms of energy, QoE, error rate, and processing time. The simulation results revealed that DQN‐QQE is more stable and is better than DQN‐Q2‐SFC and randomness approach in terms of energy, QoE, and error rate. The average processing time and energy consumption of the proposed DQN‐QQE was 43% and 11% less than DQN‐Q2‐SFC, respectively. Although brute force approach is better than others in terms of energy, QoE, and error rate, the processing time of brute force approach is nearly 20 times larger than the proposed DQN‐QQE.
Leveraging community science data for population assessments during a pandemic
Authors: Howell Paige E. , Devers Patrick K. , Robinson Orin J. , Royle J. Andrew
Published: January 2022

The COVID‐19 pandemic has disrupted field research programs, making conservation and management decision‐making more challenging. However, it may be possible to conduct population assessments using integrated models that combine community science data with existing data from structured surveys. We developed a space–time integrated model to characterize spatial and temporal variability in population distribution. We fit our integrated model to 10 years of eBird (2010–2020) and 9 years of aerial survey (2010–2019) Mottled Duck count data to forecast 2020 population size along the western Gulf Coast of Texas and Louisiana. Estimates of Mottled Duck abundance were similar in magnitude to estimates calculated using previous methods but were more precise and showed evidence of a declining population. The spatial distribution for Mottled Ducks each year was characterized by several concentrations of relatively high abundance, although the location of these abundance “hotspots” varied over time. Expected abundance was higher for areas with a higher proportion of area covered by marsh habitat. By leveraging large‐scale community science data, we were able to conduct a population assessment despite the disruption in structured surveys caused by the pandemic. As participation in community science platforms continues to increase, we anticipate modeling frameworks, like the integrated model we developed here, will become increasingly useful for informing conservation and management decision‐making.
Rodent‐mediated plant seed dispersal: What happens to the seeds after entering the gaps with different sizes?
Authors: Yu Fei , Li Guangjie , Wei Shanshan , Yi Xianfeng , Ma Jianmin , Ma Keming , Chen Guangwen
Published: January 2022

In general, it is accepted that gap formation significantly affects the placement of scatter‐hoarded seeds by small rodents, but the effects of different forest gap sizes on the seed‐eating and scatter‐hoarding behaviors of small rodents remain unclear. Thus, we examined the effects of a closed‐canopy forest, forest edge, and gaps with different sizes on the spatial dispersal of Quercus variabilis acorns and cache placement by small rodents using coded plastic tags in the Taihang Mountains, China. The seeds were removed rapidly, and there were significant differences in the seed‐eating and caching strategies between the stand types. We found that Q. variabilis acorns were usually eaten after being removed from the closed‐canopy forest and forest edges. By contrast, the Q. variabilis acorns in the forest gap stands were more likely to be scatter‐hoarded. The dispersal distances of Q. variabilis acorns were significantly longer in the forest gap plots compared with the closed canopy and forest edge plots. However, the proportion of scatter‐hoarded seeds did not increase significantly as the gap size increased. In small‐scale oak reforestation projects or research, creating small gaps to promote rodent‐mediated seed dispersal may effectively accelerate forest recovery and successional processes.
Potential risk zone for anthropogenic mortality of carnivores in Gandaki Province, Nepal
Authors: Adhikari Binaya , Baral Kedar , Bhandari Shivish , Szydlowski Michelle , Kunwar Ripu M. , Panthi Saroj , Neupane Bijaya , Koirala Raj Kumar
Published: January 2022

Anthropogenic pressures in human‐dominated landscapes often contribute to wildlife mortality. Carnivores are especially vulnerable to human‐induced mortality due to the perceived threat to livestock and humans. Despite having widespread conservation implications, carnivore mortality data have been largely underutilized within Nepal. This study utilized Maxent to identify high‐risk areas and explore the contribution of habitat attributes associated with carnivore mortality using the casualty database within the Gandaki province of central Nepal. We categorized the risk to carnivore species in three taxonomic groups, Felid, Viverridae, and Herpestidae, and identified a 3704‐km2 area within the province at high risk for carnivore casualty. The middle mountains were the riskiest physiographic zone, and the Annapurna Conservation Area represented the largest risk zone among the four protected areas. Agricultural land was the most problematic area in terms of carnivore casualty. The human population was positively associated with high‐risk areas and the number of casualties, whereas protected area cover had a negative association. This study identified that the common leopard was at the highest risk of mortality and therefore would benefit from the implementation of an action plan and species‐specific conservation strategies, especially within identified high‐risk zones. An expansion of protected areas in the middle mountain region would serve to greatly reduce carnivore casualty. Species distribution modeling can be further used with national‐level spatial and temporal mortality data to identify the most prominent casualty times and pinpoint potential casualty locations throughout the country.
Tree identity and diversity directly affect soil moisture and temperature but not soil carbon ten years after planting
Authors: Martin‐Guay Marc‐Olivier , Belluau Michaël , Côté Benoit , Handa Ira Tanya , Jewell Mark D. , Khlifa Rim , Munson Alison D. , Rivest Maxime , Whalen Joann K. , Rivest David
Published: January 2022

Soil C is the largest C pool in forest ecosystems that contributes to C sequestration and mitigates climate change. Tree diversity enhances forest productivity, so diversifying the tree species composition, notably in managed forests, could increase the quantity of organic matter being transferred to soils and alter other soil properties relevant to the C cycle.

A ten‐year‐old tree diversity experiment was used to study the effects of tree identity and diversity (functional and taxonomic) on soils. Surface (0–10 cm) mineral soil was repeatedly measured for soil C concentration, C:N ratio, pH, moisture, and temperature in twenty‐four tree species mixtures and twelve corresponding monocultures (replicated in four blocks).

Soil pH, moisture, and temperature responded to tree diversity and identity. Greater productivity in above‐ and below‐ground tree components did not increase soil C concentration. Soil pH increased and soil moisture decreased with functional diversity, more specifically, when species had different growth strategies and shade tolerances. Functional identity affected soil moisture and temperature, such that tree communities with more slow‐growing and shade‐tolerant species had greater soil moisture and temperature. Higher temperature was measured in communities with broadleaf‐deciduous species compared to communities with coniferous‐evergreen species.

We conclude that long‐term soil C cycling in forest plantations will likely respond to changes in soil pH, moisture, and temperature that is mediated by tree species composition, since tree species affect these soil properties through their litter quality, water uptake, and physical control of soil microclimates.
Size‐dependent and environment‐mediated shifts in leaf traits of a deciduous tree species in a subtropical forest
Authors: Zheng Jie , Jiang Ya , Qian Hong , Mao Yanjiao , Zhang Chao , Tang Xiaoxin , Jin Yi , Yi Yin
Published: January 2022

Aims

Understanding the joint effects of plant development and environment on shifts of intraspecific leaf traits will advance the understandings of the causes of intraspecific trait variation. We address this question by focusing on a widespread species Clausena dunniana in a subtropical broad‐leaved forest.

Methods

We sampled 262 individuals of C. dunniana at two major topographic habitat types, the slope and hilltop, within the karst forests in Maolan Nature Reserve in southwestern China. We measured individual plant level leaf traits (i.e., specific leaf area (SLA), leaf area, leaf dry‐matter content (LDMC), and leaf thickness) that are associated with plant resource‐use strategies. We adopted a linear mixed‐effects model in which the plant size (i.e., the first principal component of plant basal diameter and plant height) and environmental factors (i.e., topographic habitat, canopy height, and rock‐bareness) were used as independent variables, to estimate their influences on the shifts of leaf traits.

Key Results

We found that (1) plant size and the environmental factors independently drove the intraspecific leaf trait shifts of C. dunniana, of which plant size explained less variances than environmental factors. (2) With increasing plant size, C. dunniana individuals had increasingly smaller SLA but larger sized leaves. (3) The most influential environmental factor was topographic habitat; it drove the shifts of all the four traits examined. Clausena dunniana individuals on hilltops had leaf traits representing more conservative resource‐use strategies (e.g., smaller SLA, higher LDMC) than individuals on slopes. On top of that, local‐scale environmental factors further modified leaf trait shifts.

Conclusions

Plant size and environment independently shaped the variations in intraspecific leaf traits of C. dunniana in the subtropical karst forest of Maolan. Compared with plant size, the environment played a more critical role in shaping intraspecific leaf trait variations, and potentially also the underlying individual‐level plant resource‐use strategies.
Seedling survival simultaneously determined by conspecific, heterospecific, and phylogenetically related neighbors and habitat heterogeneity in a subtropical forest in Taiwan
Authors: Huang Teng‐He , Huang Chun‐Lin , Lin Yi‐Ching , Sun I‐Fang
Published: January 2022

Density dependence and habitat heterogeneity have been recognized as important driving mechanisms that shape the patterns of seedling survival and promote species coexistence in species‐rich forests. In this study, we evaluated the relative importance of density dependence by conspecific, heterospecific, and phylogenetically related neighbors and habitat heterogeneity on seedling survival in the Lienhuachih (LHC) Forest, a subtropical, evergreen forest in central Taiwan. Age‐specific effects of different variables were also studied. We monitored the fates of 1,642 newly recruited seedlings of woody plants within a 25‐ha Forest Dynamics Plot for 2 years. The effects of conspecific, heterospecific, and phylogenetically related neighbors and habitat heterogeneity on seedling survival were analyzed by generalized linear mixed models. Our results indicated that conspecific negative density dependence (CNDD) had a strong impact on seedling survival, and the effects of CNDD increased with seedling age. Heterospecific positive density dependence (HPDD) and phylogenetic positive density dependence (PPDD) had a significant influence on the survival of seedlings, and stronger HPDD and PPDD effects were detected for older seedlings. Furthermore, seedling survival differed among habitats significantly. Seedling survival was significantly higher in the plateau, high‐slope, and low‐slope habitats than in the valley. Overall, our results suggested that the effects of CNDD, HPDD, PPDD, and habitat heterogeneity influenced seedling survival simultaneously in the LHC subtropical forest, but their relative importance varied with seedling age. Such findings from our subtropical forest were slightly different from tropical forests, and these contrasting patterns may be attributed to differences in abiotic environments. These findings highlight the importance to incorporate phylogenetic relatedness, seedling age, and habitat heterogeneity when investigating the impacts of density dependence on seedling survival that may contribute to species coexistence in seedling communities.
Extending the application potential of capillary electrophoresis/frontal analysis for drug‐plasma protein studies by combining it with mass spectrometry detection
Authors: Mlčochová Hana , Michalcová Lenka , Glatz Zdeněk
Published: January 2022

CE/frontal analysis (CE/FA) is probably one of the most frequently used modes of CE for studying affinity interactions. It is typically performed with classic UV‐Vis detection that suffers from low concentration sensitivity. To overcome this limitation, the applicability of CE/FA in combination with ESI‐MS detection for the investigation of drug–HSA interactions was demonstrated. The developed new method combines the advantages of CE/FA, such as low sample consumption and no labeling or immobilization of interacting partners, with the benefits of MS detection, such as higher selectivity and sensitivity; moreover, it can be used for molecules lacking a fluorophore or chromophore. The binding parameters of tolbutamide (TL) and glimepiride (GLP), first‐ and second‐generation antidiabetics that differ strongly in their solubility in aqueous solutions, were investigated by this CE/FA‐MS method. This method, in contrast to the CE/FA method with the most commonly used UV‐Vis detection, is more sensitive; an almost three times lower LOD was reached. The binding parameters of TL and GLP were investigated by this CE/FA‐MS method and compared with the literature data. The binding constant value of TL obtained by UV‐Vis detection was lower than the value obtained by the method hyphenated with MS detection, which is probably given by the influence of the ESI parameters on the stability of drug–HSA complex. In addition, the ratio of TL and HSA concentrations was divergent in both of the experimental approaches. Finally, it can be concluded that both detection methods have their strengths and weaknesses.
An integrated plastic microchip for enhancing electrophoretic separation using tunable pressure‐driven backflows
Authors: Liu Yulan , Xia Ling , Xiao Xiaohua , Li Gongke
Published: January 2022

Microfluidic CE (MCE) is an effective solution for rapid and sensitive determination of multiple analytes. Herein, a dynamic coated cyclic olefin copolymer microchip was developed having an on‐chip micropump for fluid velocity adjusting in electrophoretic separations. This micropump was fabricated by constructing a polyacrylamide gel membrane at one channel terminal. Once applying electric field across the membrane, a pressure‐driven flow generated automatically to balance the electroosmotic flow (EOF) mismatch at the channel‐membrane interface. The influence of gel precursor concentration and operating voltages on the fluid velocity was carefully evaluated. Moreover, the highly integration of injection, separation, and pumping units of the MCE system minimized the dead volume and provides satisfied column efficiency. Experiments showed that by adjusting of pumping voltage reduced the fluid velocity by a factor of 6, resulting six‐ and threefold resolving power enhancements of rhodamine dye mixture and amino acid mixture, respectively. Furthermore, the developed MCE method was applied for rhodamines and amino acids quantitation in food and cosmetics, with standard addition recoveries of 87.3–106.9% and 89.9–117.4%, respectively. These results were also confirmed by standard HPLC method, revealing the application potential in fast and onsite analysis of complex samples.
Polymer coating with gradient‐dispersed dielectric nanoparticles for enhanced daytime radiative cooling
Authors: Fu Yang , An Yidan , Xu Yunkun , Dai Jian‐Guo , Lei Dangyuan
Published: January 2022

Polymeric coatings with randomly distributed dielectric nanoparticles have attracted intensive attention in the passive daytime radiative cooling application. Here, we propose a modified Monte–Carlo method for investigating the spectral response and cooling performance of polymer coating with gradient‐dispersed nanoparticles. Using this method, we carry out a quantitative analysis on the solar reflectance, infrared emittance and cooling power of four categories of gradient structures. It is shown that the gradient profile of particle distribution at the near‐surface region has a significant influence on the overall performance of the coatings. Compared to a randomly distributed structure, the downward size‐gradient structure exhibits superiority in both solar reflectance and cooling power. The presented gradient design, also applicable to porous structures, provides an effective and universal strategy for significantly improving the cooling performance of radiative cooling coatings.

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Assembling metal‐polyphenol coordination interfaces for longstanding zinc metal anodes
Authors: Huyan Yu , Wang Jian‐Gan , Tian Shan , Ren Lingbo , Liu Huanyan , Wei Bingqing
Published: January 2022

Zn metals have gained the immense attention of researchers for their wide employment as the anode of high‐performance aqueous batteries. Nonetheless, the Zn anodes suffer from uncontrollable dendrite growth and parasitic side reactions, which substantially shorten the battery lifespan. This study proposes an interfacial assembly of a metal‐polyphenol coordination coating on Zn anodes to regulate Zn2+ deposition behavior. Bismush‐coordinated polyphenolic ligands (i.e., tannic acid, TA) create a functional interface that could promote Zn's uniform nucleation and plating/striping kinetics. Moreover, the artificial coating acts as a physical barrier to inhibit surface corrosion. As a consequence, the TA‐Bi‐modified Zn anodes display a small voltage hysteresis of ~38 mV at 1 mA cm−2 over 2600 h and an ultra‐long lifespan for 3100 h (~4.3 months) even at a high‐current density of 10 mA cm−2. When assembled with a vanadium‐based cathode, the full Zn‐ion batteries achieve improved electrochemical performance.

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Defect object detection algorithm for electroluminescence image defects of photovoltaic modules based on deep learning
Authors: Meng Ziyao , Xu Shengzhi , Wang Lichao , Gong Youkang , Zhang Xiaodan , Zhao Ying
Published: January 2022

Visual inspection of photovoltaic modules using electroluminescence (EL) images is a common method of quality inspection. Because human inspection requires a lot of time, object detection algorithm to replace human inspection is a popular research direction in recent years. To solve the problem of low accuracy and slow speed in EL image detection, we propose a YOLO‐based object detection algorithm YOLO‐PV, which achieves 94.55% of AP (average precision) on the photovoltaic module EL image data set, and the interference speed exceeds 35 fps. The improvement of speed and accuracy benefits from the targeted design of the network architecture according to the characteristics of EL image. First, we weaken the backbone's ability to extract deep‐level information so that it can focus on extracting the low‐level defect information. Second, the PAN network is used for feature fusion in the Neck part. But, only the single‐size feature map output is retained, which significantly reduces the amount of calculation. Also, we analyze the impact of data enhancement methods on model overfitting and performance. Finally, we give effective data enhancement methods. The results show that the object detection algorithm in this paper can meet the requirements for high‐precision and real‐time processing on the PV module production line.
Individual and Combined Effects of Manganese and Chromium on a Freshwater Chlorophyceae
Authors: Alho Lays de Oliveira Gonçalves , Gebara Renan Castelhano , Mansano Adrislaine da Silva , Rocha Giseli Swerts , Melão Maria da Graça Gama
Published: January 2022

Manganese (Mn), an essential metal in trace amounts, and chromium (Cr), a nonessential metal to algae, are often found in effluent discharges and may co-occur in contaminated aquatic environments. Therefore, we investigated the effects of Mn and Cr, and their mixtures, on a freshwater Chlorophyceae, Raphidocelis subcapitata, using a multiple endpoint approach. Regarding the single exposure of metals, Mn was 4 times more toxic (median inhibitory concentration at 72 h [IC5072 h] = 4.02 ± 0.45 µM Mn) than Cr (IC5072 h = 16.42 ± 4.94 µM Cr) for microalgae, considering the effects on the relative growth rate. Moreover, this species was the most sensitive to Mn, according to the species sensitivity distribution curve. Overall, the tested metals did not lead to significant changes in reactive oxygen species production, cellular complexity, and cell relative size but significantly decreased the algal growth and the mean cell chlorophyll a (Chl a) fluorescence at the highest concentrations (3.64–14.56 µM of Mn and 15.36–19.2 µM of Cr). The decreased mean cell Chl a fluorescence indicates an impact on pigment synthesis, which may be related to the observed growth inhibition. In the mixture tests, the reference models concentration addition and independent action were used to analyze the data, and the independent action model was the best fit to describe our results. Therefore, the Mn and Cr mixture was noninteractive, showing additive effects. This is the first study to address the combined toxicity of Mn and Cr regarding freshwater Chlorophyceae. Environ Toxicol Chem 2022;41:1004–1015. © 2022 SETAC
Developing a novel direct liquid fuel cell based on pulping liquors
Authors: Oliveira Raisa C.P. , Jeremias Maria J. , Mateus Maria Margarida , Santos Diogo M.F.
Published: January 2022

This work reports preliminary studies to develop new direct liquid fuel cells that employ two by‐products from kraft and sulfite pulp mills as the fuel, namely kraft black liquor (BL) and spent sulfite liquor (SSL). The composition and properties of BL and SSL are characterized, being determined a conductivity 40 times higher for BL than for SSL. The performance of the BL fuel cell (BLFC) and the SSL fuel cell (SSLFC) is assessed employing 5 M hydrogen peroxide solution as the oxidant at different pH values. For the BLFC, an anion‐exchange membrane (AEM) is used, and for the SSLFC, both AEM and cation‐exchange membrane (CEM) are tested. Different parameters that characterize the fuel cell performance (e.g., peak power density) are determined and compared with similar wastewater‐based fuel cells described in the literature. To the best of the authors’ knowledge, it is the first time two pulp mill by‐products (BL and SSL) are reported as fuels for application in fuel cells.
Poor treatment tolerance in head and neck cancer patients with low muscle mass
Authors: Mascarella Marco A. , Patel Terral , Vendra Varun , Gardiner Lauren , Kergoat Marie‐Jeanne , Kubik Mark W. , Solari Mario G. , Snyderman Carl H. , Traylor Katie S. , Ferris Robert L. , Kim Seungwon , Duvvuri Umamaheswar , Sridharan Shaum S.
Published: January 2022

Background

We ascertain the role of a low cervical paraspinal skeletal muscle index (CPSMI) as a biomarker for poor treatment tolerance in patients with operable mucosal head and neck squamous cell carcinoma (HNSCC).

Methods

A prospective cohort of patients with operable HNSCC requiring microvascular reconstruction was evaluated. Low CPSMI was calculated using preoperative CT neck imaging. Poor treatment tolerance, a composite measure of incomplete therapy or severe morbidity/mortality during treatment, was the primary outcome.

Results

One hundred and twenty‐seven patients underwent extirpative surgery with a mean age was 60.5. Poor treatment tolerance occurred in 71 (56%) patients with 21 not completing recommended adjuvant therapy and 66 having severe treatment‐related morbidity. A low CPSMI was independently associated with poor treatment tolerance (OR 2.49, 95%CI 1.10–5.93) and delay to adjuvant therapy (OR 4.48, 95%CI 1.07–27.6) after adjusting for multiple confounders.

Conclusion

Low CPSMI was independently associated with poor treatment tolerance in patients with operable HNSCC.
Hepatocyte TGF‐β Signaling Inhibiting WAT Browning to Promote NAFLD and Obesity Is Associated With Let‐7b‐5p
Authors: Zhao Jinfang , Hu Lilin , Gui Wenfang , Xiao Li , Wang Weijun , Xia Jing , Fan Huiqian , Li Zhonglin , Zhu Qingjing , Hou Xiaohua , Chu Huikuan , Seki Ekihiro , Yang Ling
Published: January 2022

Transforming growth factor beta (TGF‐β) signaling in hepatocytes promotes steatosis and body weight gain. However, processes that TGF‐β signaling in hepatocytes promote pathological body weight gain in nonalcoholic fatty liver disease (NAFLD) are incompletely understood. Obesity and NAFLD were induced by 16 weeks of feeding a high‐fat diet (HFD) in hepatocyte‐specific TGF‐β receptor II–deficient (Tgfbr2ΔHEP
) and Tgfbr2flox/flox
mice. In addition, browning of white adipose tissue (WAT) was induced by administration of CL‐316,243 (a β3‐adrenergic agonist) or cold exposure for 7 days. Compared with Tgfbr2 flox/flox
mice, Tgfbr2ΔHEP
mice were resistant to steatosis and obesity. The metabolic changes in Tgfbr2ΔHEP
mice were due to the increase of mitochondrial oxidative phosphorylation in the liver and white‐to‐beige fat conversion. A further mechanistic study revealed that exosomal let‐7b‐5p derived from hepatocytes was robustly elevated after stimulation with palmitic acid and TGF‐β. Indeed, let‐7b‐5p levels were low in the liver, serum exosomes, inguinal WAT, and epididymal WAT in HFD‐fed Tgfbr2ΔHEP
mice. Moreover, 3T3‐L1 cells internalized hepatocyte‐derived exosomes. An in vitro experiment demonstrated that let‐7b‐5p overexpression increased hepatocyte fatty acid transport and inhibited adipocyte‐like cell thermogenesis, whereas let‐7b‐5p inhibitor exerted the opposite effects. Conclusion: Hepatocyte TGF‐β‐let‐7b‐5p signaling promotes HFD‐induced steatosis and obesity by reducing mitochondrial oxidative phosphorylation and suppressing white‐to‐beige fat conversion. This effect of hepatocyte TGF‐β signaling in metabolism is partially associated with exosomal let‐7b‐5p.
Food security, mental health, and socioeconomic status: A cross‐sectional study among medical college students in central part of Iran, Kashan
Authors: Amin Negin , Akbari Hossein , Jafarnejad Sadegh
Published: January 2022

Background and Aims

Food security is a complex and multidimensional issue that has been recognized as a serious public health problem all over the world for the past two decades. The present study was designed and conducted to determine the prevalence of food insecurity among college students at the Kashan University of Medical Sciences and some related factors including socioeconomic and mental health determinants.

Methods

The present study is a cross‐sectional study conducted on 358 students who were currently studying at the Kashan University of Medical Sciences. The students who were pregnant or had a special diet to follow were excluded. Samples were selected by the systematic method. Food security was measured using United States Department of Agriculture. Food Frequency Questionnaire, 21‐items Depression Anxiety Stress Scales, and Socioeconomic Questionnaire were used to investigate the nutrients intake, depression/anxiety status, and socioeconomic factors, respectively. Chi‐square, independent t‐test, and logistic regression were used to analyze the data.

Results

Based on the findings of the present study, 16.8% of students experienced different levels of food insecurity, and 83.2% of participants were categorized as food secure. Gender, financial assistance, health insurance, depression, and students' occupation are associated with food insecurity (P < .05). Additionally, the results of the logistic regression analysis showed that depression (OR 1.04; 95% CI 1.01‐1.07), and students' jobs (OR 0.43; 95% CI 0.23‐0.80) have the greatest impact on students' food insecurity.

Conclusion

The findings of the present study show that economic factors and gender have a significant impact on students' food security. Moreover, the association of food insecurity with mental disorders such as depression was demonstrated in the current study. However, we could not detect any significant association between daily energy intake and macronutrients which indicates the requirement for more detailed studies.
Family risk and early attachment development: The differential role of parental sensitivity
Authors: Gerlach Jennifer , Fößel Judith M. , Vierhaus Marc , Sann Alexandra , Eickhorst Andreas , Zimmermann Peter , Spangler Gottfried
Published: January 2022

Family risks are known to be detrimental to children's attachment development. This study investigated whether parental sensitivity plays different roles in early attachment development in the context of risk: Sensitivity was hypothesized to mediate risk effects on attachment, as well as a moderator that shapes the relation between risk and attachment. Multiple family risks, parental sensitivity (defined as responsivity and supportive presence), and children's attachment security of 197 infants and toddlers (Mage = 15.25 months) and their caregivers were assessed in a prospective study with a cohort‐sequential‐design in Germany. Caregivers' sensitivity served as a mediator of risk effects on attachment as well as a moderator that buffers adverse consequences of risk. Early sensitivity might be relevant in setting the stage for attachment development supporting resilience.
Modelling Cyber‐Physical Systems Using Data‐driven Patterns
Authors: Semeraro Concetta , Lezoche Mario , Panetto Hervé , Dassisti Michele
Published: January 2022

Modelling Cyber‐physical systems is quite complex and thus needs a big amount of data and modelling techniques representing the operational semantics of the modelled elements. Generally, the modelling action has a specific application type. For this reason, the paper proposes a series of modelling patterns aimed at automatically identifying invariant behaviors in the masses of data that can be modelled to emulate cyber‐physical systems and thus contribute to the digital transformation of industrial production companies.
A Semantic Model Framework for the Cyber‐Physical Production System in the Systems Engineering Perspective
Authors: SA Puviyarasu , da Cunha Catherine
Published: January 2022

A cyber‐physical production system (CPPS) is a system of digital and physical components with networked connections. These components are deeply intertwined and operate in situation‐dependent ways across all production levels. The system behavior is complex due to its dependencies and the relationship between its parts and their environment. The diversified components and their relationship lead to challenges for the involved actors in system development, operation, and end of life phases. There is a need for a generic semantic model framework to provide a unified description of all aspects and properties of the CPPS. In this paper, an overview and expected outcome of semantic model framework is presented. As a first step, the core elements, and boundaries of the CPPS are proposed. Based on a fundamental concept of systems engineering, the core elements are defined as a System of Interest (SOI) and Enabling Systems (ES).
Contribution to Nuclear Safety Demonstration Through System Modelling and Artificial Intelligence
Authors: Roumili Emir , Bossu Jean‐François , Chapurlat Vincent , Daclin Nicolas , Tixier Jérôme , Plana Robert
Published: January 2022

Nuclear Power Plant (NPP) engineering projects become increasingly complex. For instance, a nuclear reactor includes more than 50 buildings, 500 km of piping, 500,000 components and 100 million units of data (requirements, reports, schemes …). However, nuclear safety demonstration of any nuclear facility is at the heart of the nuclear industry, being the most important and limiting factor for all requested engineering activities. Ensuring all these activities are performed considering safety demonstration is mandatory to get permission to license, build, operate, dismantle, and more. This article synthetizes an innovative method that mixes and takes advantages of artificial intelligence techniques and systems engineering principles, processes, and model‐based systems engineering (MBSE) principles and usages. This method aims to guide and support engineers to improve their vision, their knowledge and vocabulary, and their capacities in terms of, first, safety requirements elicitation, and second of safety requirements demonstration.
Near infrared spectroscopy reveals instability in retinal mitochondrial metabolism and haemodynamics with blue light exposure at environmental levels
Authors: Kaynezhad Pardis , Fosbury Robert , Hogg Chris , Tachtsidis Ilias , Sivaprasad Sobha , Jeffery Glen
Published: January 2022

Blue light (~400‐470 nm) is considered potentially detrimental to the retina but is present in natural environmental light. Mitochondrial density is highest in the retina, and they exhibit a prominent optical absorption around 420 nm arising from the Soret band of their porphyrins, including in cytochrome‐c‐oxidase in their respiratory chain. We examine the impact of continuous 420 nm at environmental energy levels on retinal mitochondrial metabolism and haemodynamics in vivo in real time using broadband near‐infrared spectroscopy. One hour environmental exposure to 420 nm induces significant metabolic instability in retinal mitochondria and blood signals, which continues for up to 1 h post blue exposure. Porphyrins are important in mitochondrial adenosine triphosphate (ATP) production and cytochrome‐c‐oxidase is a key part of the electron transport chain through which this is achieved. Hence, environmental 420 nm likely restricts respiration and ATP production that may impact on retinal function.
An autofocus algorithm considering wavelength changes for large scale microscopic hyperspectral pathological imaging system
Authors: Zhang Qing , Wang Yan , Li Qingli , Tao Xiang , Zhou Xiufeng , Zhang Yonghe , Liu Gang
Published: January 2022

Microscopic hyperspectral imaging technology has been widely used to acquire pathological information of tissue sections. Autofocus is one of the most important steps in microscopic hyperspectral imaging systems to capture large scale or even whole slide images of pathological slides with high quality and high speed. However, there are quite few autofocus algorithm put forward for the microscopic hyperspectral imaging system. Therefore, this article proposes a Laplace operator based autofocus algorithm for microscopic hyperspectral imaging system which takes the influence of wavelength changes into consideration. Through the proposed algorithm, the focal length for each wavelength can be adjusted automatically to ensure that each single band image can be autofocused precisely with adaptive image sharpness evaluation method. In addition, to increase the capture speed, the relationship of wavelength and focal length is derived and the focal offsets among different single band images are calculated for pre‐focusing. We have employed the proposed method on our own datasets and the experimental results show that it can capture large‐scale microscopic hyperspectral pathology images with high precise.
Design and evaluation of nanostructured lipid carriers loaded with Salvia officinalis extract for Alzheimer's disease treatment
Authors: Markova Elena , Taneska Lea , Kostovska Monika , Shalabalija Dushko , Mihailova Ljubica , Glavas Dodov Marija , Makreski Petre , Geskovski Nikola , Petrushevska Marija , N. Taravari Arben , Simonoska Crcarevska Maja
Published: January 2022

Considering the potential of Salvia officinalis in prevention and treatment of Alzheimer's disease (AD), as well as the ability of nanostructured lipid carriers (NLC) to successfully deliver drug molecules across blood–brain barrier (BBB), the objective of this study was design, development, optimization and characterization of freeze‐dried salvia officinalis extract (FSE) loaded NLC intended for intranasal administration. NLC were prepared by solvent evaporation method and the optimization was carried out using central composite design (CCD) of experiments. Further, the optimized formulation (NLCo) was coated either with chitosan (NLCc) or poloxamer (NLCp). Surface characterization of the particles demonstrated a spherical shape with smooth exterior. Particle size of optimal formulations after 0.45 μm pore size filtration ranged from 127 ± 0.68 nm to 140 ± 0.74 nm. The zeta potential was −25.6 ± 0.404 mV; 22.4 ± 1.106 mV and − 6.74 ± 0.609 mV for NLCo, NLCc, and NLCp, respectively. Differential scanning calorimetry (DSC) confirmed the formation of NLC whereas Fourier‐transform infrared spectroscopy confirmed the FSE encapsulation into particles. All formulations showcased relatively high drug loading (>86.74 mcg FSE/mg solid lipid) and were characterized by prolonged and controlled release that followed Peppas‐Sahlin in vitro release kinetic model. Protein adsorption studies revealed the lowest adsorption of the proteins onto NLCp (43.53 ± 0.07%) and highest protein adsorption onto NLCc (55.97 ± 0.75%) surface. The modified ORAC assay demonstrated higher antioxidative activity for NLCo (95.31 ± 1.86%) and NLCc (97.76 ± 4.00%) as compared to FSE (90.30 ± 1.53%). Results obtained from cell cultures tests pointed to the potential of prepared NLCs for FSE brain targeting and controlled release.