bluuebunny/crossref_metadata_2025 huggingface dataset:
Groundwater‐controlled phosphorus release and transport from sandy aquifer into lake
Authors: Kazmierczak Jolanta , Postma Dieke , Müller Sascha , Jessen Søren , Nilsson Bertel , Czekaj Joanna , Engesgaard Peter
Published: April 2020

Awareness of groundwater‐borne dissolved inorganic phosphorus (DIP) loadings into lakes and its role in lake eutrophication is increasing, albeit DIP of natural origin is often ignored. Release of geogenic DIP from an adjacent aquifer and its transport with groundwater into a eutrophic lake is described by combining hydrogeochemical data collected in this study (sampling of piezometers, hydrogeochemical profiles, and seepage meters) with groundwater flow and discharge rates from earlier studies. The major part of the DIP that entered the lake with discharging groundwater was mobilized from iron hydroxides reduced by organic matter buried in the sediments of the old lake bottom. This is indicated by the correlation between DIP and ferrous iron (Fe2+) concentrations, with a DIP/Fe2+ molar ratio of 0.06, and an increase in pH. One‐dimensional reactive transport modeling indicated that high discharge rates (> 0.1 m d−1) of anoxic groundwater upwelling in areas adjacent to the lakeshore prevent downward diffusion of oxygen into the aquifer and do not leave enough time for DIP to become rebounding to the mineral phases at the sediment‐water interface. The groundwater‐controlled DIP input into the lake calculated along a two‐dimensional cross‐section averaged 0.01 mol DIP m−2 yr−1. A 2 m wide offshore high discharge zone delivered approximately 13% of the DIP into the lake. The continuous, external loading of geogenic DIP sustains lake eutrophication and explains the failure of two previous lake restoration attempts.
Nutrient enrichment offsets the effects of low light on growth of the kelp Ecklonia radiata
Authors: Blain Caitlin O. , Shears Nick T.
Published: April 2020

Increased input of terrigenous matter and pollution into coastal marine ecosystems results in both a decline in benthic irradiance and an influx of nutrients. Though low light conditions have been demonstrated to have adverse effects on benthic primary producers, associated increases in nutrients may alleviate some of this stress by enhancing growth and productivity. We examined the interactive effect of low light and increased nitrogen (N) availability on the growth and physiological response of the kelp Ecklonia radiata using field and mesocosm experiments. Nutrient enrichment had positive effects on the growth of E. radiata in both experiments regardless of light treatment, though increases were c. 50% higher at low light. In contrast, the ability of E. radiata to acclimate to low light and net primary production (NPP) was not affected by nutrient addition, but NPP was over 2 times greater in high light treatments than low light treatments. In low light conditions, E. radiata allocated a higher proportion of assimilated C to growth compared to those in high light conditions and this was accentuated with N‐enrichment. These results indicate that growth, rather than photosynthesis, in E. radiata is limited by N availability and may also indicate a low light coping strategy whereby E. radiata invest more energy into the development of photosynthetically active tissues in order to increase photosynthetic potential. Thus, nutrient enrichment associated with increased turbidity may alleviate some of the stresses associated with living under low light and facilitate the persistence of E. radiata in turbid environments.
A Robust Carbon Nanotube and PVDF‐HFP Nanofiber Composite Superwettability Membrane for High‐Efficiency Emulsion Separation
Authors: Wang Yaqiong , Yue Guichu , Li Dianming , Hou Lanlan , Zhao Xiaochen , Cui Zhimin , Bai Jie , Wang Nü , Zhao Yong
Published: April 2020

Oil or chemical purification is significant not only for industrial safety production but also because it conforms to the principle of sustainable development. In this paper, based on the synergistic concept of superwettability and nanopores sieve effect, a superoleophilic and under‐oil superhydrophobic carbon nanotube/poly(vinylidene fluoride‐co‐hexafluoropropylene) nanofiber composite membrane is prepared via electrospinning, pressure‐driven filtration, and chemical vapor modification. The as‐prepared membrane with durable mechanical and chemical stabilities achieves separation efficiency higher than 99.9% and high flux up to 632.5 L m−2 h−1 bar−1 for different water‐in‐oil emulsions. This membrane is highly promising for the petroleum and chemical industries for both product quality improvement and green recycling manufacturing processes.
Exploring a broader context of the home environment and its relationship with asthma control in American Indian children
Authors: Brooks Jada L. , Asafu‐Adjei Josephine , Currin Emily G. , Beeber Linda S.
Published: April 2020

In this cross‐sectional study of 60 American Indian mother‐child dyads from Southeastern North Carolina, we examined whether childhood asthma control was related to household‐level factors, such as environmental tobacco smoke and family management behaviors. We also examined the relationships among family management behaviors and maternal depressive symptoms. We used logistic regression to assess the relationships among childhood asthma control, the presence of environmental tobacco smoke, and family management behaviors, specifically condition management ability (CMA) and condition management effort (CME). We used linear regression to evaluate the relationships between both CMA and CME and maternal depressive symptoms. Better asthma control in children was associated with the absence of environmental tobacco smoke in the home and the maternal perception of asthma as a manageable condition. Mothers perceived an increase in effort to manage their child's asthma as their depressive symptoms increased. These findings emphasize the importance of environmental triggers, perceptions of condition management, and maternal mental health in controlling asthma in American Indian children. Interventions to reduce environmental triggers, treat maternal depressive symptoms, and support mothers in their ability to manage childhood asthma may yield better asthma control and help to reduce existing racial disparities in this population.
Highly efficient alginate‐based macromolecular photoinitiator for crosslinking and toughening gelatin hydrogels
Authors: Huang Xing , Zhang Yuxi , Li Feng , Zhang Jun , Dai Yuhua , Shi Mengquan , Zhao Yuxia
Published: April 2020

Constructing gelatin hydrogels through photopolymerization is getting increasingly attractive due to their excellent biocompatibility and unparalleled flexibility in fabricating complex structures. In this study, an alginate‐based macromolecular photoinitiator (Alg‐2959) is synthesized by grafting Irgacure2959, a widely used hydrophilic small molecular photoinitiator, onto the framework of alginate. The characterization of Alg‐2959 is carried out by 1H nuclear magnetic resonance (1HNMR), Fourier infrared spectroscopic (FTIR), Thermogravimetric analysis (TGA), and UV–Vis absorption spectrum. It is shown that Alg‐2959 can induce the polymerization of acrylate monomer poly(ethylene glycol) diacrylate (PEGDA400) and glycidyl methacrylate modified gelatin (Gel‐GM) with similar initiation efficiency as Irgacure2959. Compared with the pure hydrogels prepared using Irgacure2959, the hybrid hydrogels containing Alg‐2959 can be further crosslinked by Ca2+ to form the double‐network hydrogels, which exhibit enhanced toughness and elasticity. In addition, due to the introduction of alginate, the migration stability of Alg‐2959 in the hydrogel networks is significantly improved compared with Irgacure2959. These results indicate the great potential of Alg‐2959 in preparing biocompatible and resilient photopolymers.
Highly Selective Photoreduction of CO2 with Suppressing H2 Evolution by Plasmonic Au/CdSe–Cu2O Hierarchical Nanostructures under Visible Light
Authors: Wang Hongzhi , Rong Hongpan , Wang Dong , Li Xinyuan , Zhang Erhuan , Wan Xiaodong , Bai Bing , Xu Meng , Liu Jiajia , Liu Jia , Chen Wenxing , Zhang Jiatao
Published: April 2020

Here, the photocatalytic CO2 reduction reaction (CO2RR) with the selectivity of carbon products up to 100% is realized by completely suppressing the H2 evolution reaction under visible light (λ > 420 nm) irradiation. To target this, plasmonic Au/CdSe dumbbell nanorods enhance light harvesting and produce a plasmon‐enhanced charge‐rich environment; peripheral Cu2O provides rich active sites for CO2 reduction and suppresses the hydrogen generation to improve the selectivity of carbon products. The middle CdSe serves as a bridge to transfer the photocharges. Based on synthesizing these Au/CdSe–Cu2O hierarchical nanostructures (HNSs), efficient photoinduced electron/hole (e−/h+) separation and 100% of CO selectivity can be realized. Also, the 2e−/2H+ products of CO can be further enhanced and hydrogenated to effectively complete 8e−/8H+ reduction of CO2 to methane (CH4), where a sufficient CO concentration and the proton provided by H2O reduction are indispensable. Under the optimum condition, the Au/CdSe–Cu2O HNSs display high photocatalytic activity and stability, where the stable gas generation rates are 254 and 123 µmol g−1 h−1 for CO and CH4 over a 60 h period.
Fecal progesterone and estrogen metabolite monitoring for cyclicity and pregnancy in southern tamandua (Tamandua tetradactyla)
Authors: Daly‐Crews Kim , Edell R. Harrison , Metrione Lara C.
Published: April 2020

Reproductive management of the southern tamandua (Tamandua tetradactyla) should include timed introductions for breeding to minimize aggression and pregnancy monitoring. Since serial blood sampling could cause unnecessary stress, and urinary progesterone metabolites are found in very low concentrations, this study sought to validate progesterone and estradiol enzyme immunoassays for measuring fecal progesterone metabolite (FPM) and fecal estrogen metabolite (FEM) concentrations in two females. Peaks in FEM concentrations coincided with breeding and conception, were 5–6 times higher than baseline concentrations, and were followed by clear luteal phases distinguished by FPM concentrations 5–6 times higher than baseline concentrations. FPM concentrations during the first 30–53 days of gestation overlapped with luteal phase concentrations, thereafter increasing to 8–25 times higher than baseline concentrations. FEM concentrations during the first 41–44 days of gestation remained near basal values for one female, whereas concentrations were 1.8 times higher than baseline for the second. FEM concentrations became elevated for the former by 44 days of gestation and increased further for the latter after 53 days, ultimately averaging four times higher than baseline for both females. The biphasic increase in FPM and FEM concentrations, follicular and luteal phase durations (follicular: 7 ± 1 days, luteal: 25 ± 1 days), total cycle length (41 ± 1 days), and gestation (161–165 days) documented in this study were consistent with previous reports from serum and urine analyses. Monitoring FPM and FEM is a reliable noninvasive method for tracking reproductive cycles and pregnancy in southern tamandua that overcomes the challenges associated with serum or urinary hormone analysis.
CRISPR interference-based gene repression in the plant growth promoter Paenibacillus sonchi genomovar Riograndensis SBR5
Authors: Brito Luciana F. , Schultenkämper Kerstin , Passaglia Luciane M. P. , Wendisch Volker F.
Published: April 2020

Gene repression using the endonucleolytically deactivated dCas9 protein and sgRNAs (CRISPR interference or CRISPRi) is a useful approach to study gene functions. Here, we established CRISPRi in Paenibacillus sonchi genomovar Riograndensis SBR5, a plant growth promoting bacterium. CRISPRi system with sgRNAs targeting SBR5 endogenous genes spo0A, yaaT and ydjJ and plasmid-borne gfpUV was constructed and analyzed. Flow cytometry analysis revealed a significant decrease of reporter protein GFPUV signal in P. sonchi strains expressing gfpUV sgRNA in comparison with non-targeting controls. CRISPRi-based repression of chromosomal genes for regulation of sporulation spo0A and yaaT decreased sporulation and increased biofilm formation in SBR5. Repression of the sorbitol catabolic gene ydjJ revealed decreased specific activity of YdjJ in crude cell extracts and reduced biomass formation from sorbitol in growth experiments. Our work on CRISPRi-based gene repression serves as basis for gene function studies of the plant growth promoter P. sonchi SBR5. To our knowledge, the present study presents the first tool for gene repression established in Paenibacillus species.Key points• CRISPRi toward gene repression was applied for the first time in Paenibacillus.• CRISPRi of spo0A and yaaT depleted spores and increased biofilms in SBR5.• CRISPRi-based ydjJ repression decreased specific activity of sorbitol dehydrogenase.
Conserved roles of chromatin remodellers in cohesin loading onto chromatin
Authors: Muñoz Sofía , Passarelli Francesca , Uhlmann Frank
Published: April 2020

Cohesin is a conserved, ring-shaped protein complex that topologically entraps DNA. This ability makes this member of the structural maintenance of chromosomes (SMC) complex family a central hub of chromosome dynamics regulation. Besides its essential role in sister chromatid cohesion, cohesin shapes the interphase chromatin domain architecture and plays important roles in transcriptional regulation and DNA repair. Cohesin is loaded onto chromosomes at centromeres, at the promoters of highly expressed genes, as well as at DNA replication forks and sites of DNA damage. However, the features that determine these binding sites are still incompletely understood. We recently described a role of the budding yeast RSC chromatin remodeler in cohesin loading onto chromosomes. RSC has a dual function, both as a physical chromatin receptor of the Scc2/Scc4 cohesin loader complex, as well as by providing a nucleosome-free template for cohesin loading. Here, we show that the role of RSC in sister chromatid cohesion is conserved in fission yeast. We discuss what is known about the broader conservation of the contribution of chromatin remodelers to cohesin loading onto chromatin.
Analysis of motives and patient satisfaction in oncological second opinions provided by a certified university breast and gynecological cancer center
Authors: Loehberg Christian R. , Meyer Julia , Häberle Lothar , Hack Carolin C. , Jud Sebastian , Hein Alexander , Wunderle Marius , Emons Julius , Gass Paul , Fasching Peter A. , Egloffstein Sainab , Krebs Jessica , Erim Yesim , Beckmann Matthias W. , Lux Michael P. , Wasner Sonja
Published: April 2020

Purpose

Second opinions in oncology are becoming increasingly important in an era of more complex treatments and a growing demand for information by patients. Therefore, we analyzed their effects and influencing factors like patients’ motives, subjective extent of information and satisfaction with communications.

Methods

This prospective study evaluated second opinions for patients with breast cancer or gynecological malignancy. The patients received a questionnaire before and two months after, which inquired expectations, reasons, and satisfaction with the second opinion and the attending physicians.

Results

A total of 164 patients were included and the majority had breast cancer (75.0%). Receiving the second opinion made 89.7% feel better informed, their need for information decreased (from 75.3% to 39.2%, P < 0.0001), and satisfaction with doctor–patient communications increased (from 61.9 to 91.8%, P = 0.0002). There were various reasons for requesting a second opinion, e.g., the extremely stressful situation of a cancer diagnosis, hope for change in the treatment recommendation or dissatisfaction with the initial physicians.

Conclusions

Second opinions can lead to significantly greater patient satisfaction, meeting the need for information and leading to better management of patients in the extremely stressful situation of a cancer diagnosis. Doctor–patient communications play a key role.
The prevention of musculoskeletal complaints: long-term effect of a work-related psychosocial coaching intervention compared to physiotherapy alone—a randomized controlled trial
Authors: Becker Annette , Angerer Peter , Weber Jeannette , Müller Andreas
Published: April 2020

Purpose

Research shows that psychosocial factors play a significant role in the emergence of musculoskeletal complaints (MSC). The aim of this study was to determine the long-term effects on unspecific MSC by a combined physiotherapy and coaching intervention compared to physiotherapy alone. The coaching intervention focussed on enabling better strategies for coping with work stressors.

Methods

The participants of a previous randomized controlled intervention were invited to participate again in a third follow-up survey 22 months after the end of the intervention. In 2014, 65 nurses completed a 10-week personalised physiotherapy. Additionally, the intervention group (n = 33) passed five individual coaching sessions, plus an opening and closing session. 44 nurses (IG: n = 24; CG: n = 20) passed again a physical examination as well as another questionnaire assessment in 2016. The primary outcome was MSC, secondary outcomes were work ability and work-related well-being. Due to missing data, multiple imputations were conducted using the mice package in R. Data were analysed by ANOVA with two-way repeated measures, t tests for independent samples and Chi-squared tests.

Results

In respect of MSC, stronger improvement of movement in the vertebral column was observed in the IG compared to the CG. No differences between the IG and CG regarding other long-term effects were observed.

Conclusions

The results suggest that the combined intervention of work-related coaching and physiotherapy had only a marginally stronger long-term effect with respect to MSC than physiotherapy alone.
Parental effects influence life history traits and covary with an environmental cline in common frog populations
Authors: Rowiński Piotr K. , Laurila Anssi , Gotthard Karl , Sowersby Will , Lind Martin I. , Richter-Boix Alex , Eckerström-Liedholm Simon , Rogell Björn
Published: April 2020

Across latitudinal clines, the juvenile developmental rates of ectotherms often covary with the length of the growing season, due to life-history trade-offs imposed by the time-constrained environments. However, as the start of the growing season often varies substantially across years, adaptive parental effects on juvenile developmental rates may mediate the costs of a delayed season. By employing a meta-analysis, we tested whether larval developmental rates across a latitudinal cline of the common frog (Rana temporaria) are affected by fluctuating onsets of breeding, across years. We predicted that larval developmental rate will be inversely related to the onset of breeding, and that northern populations will be more prone to shorten their developmental rate in response to late breeding, as the costs of delayed metamorphosis should be highest in areas with a shorter growing season. We found that the larval period of both northern and southern populations responded to parental environmental conditions to a similar degree in absolute terms, but in different directions. In northern populations,a late season start correlated with decreased development time, suggesting that the evolution of parental effects aids population persistence in time-constrained environments. In southern populations, late season start correlated with increased development time, which could potentially be explained as a predator avoidance strategy. Our findings suggest that local ecological variables can induce adaptive parental effects, but responses are complex, and likely trade-off with other ecological factors.
Towards an Acoustic Simulation of a Water Drop Impacting in a Water Pool
Authors: Friedrich Jonas , Schäfer Michael
Published: April 2020

The sound which is produced when a water drop impacts into a water pool is a prominent example for acoustics produced by multiphase flow. In this work the feasibility of numerical methods for simulating this challenging test case is evaluated. First the multiphase flow needs to produce the correct physical mechanisms, e.g. the bubble entrapment. For this an in-house block-structured finite-volume solver with the volume-of-fluid method is used. For the curvature computation a standard finite difference method within the continuum surface force model is employed, including some necessary improvements. A high resolution in space and time is essential and therefore the method is parallelized by domain decomposition. The acoustic part is simulated with the linearized Euler equations which are valid in each phase but need to be adapted in the interface region. The results are compared with numerical and experimental data. It is shown, that the methods are suitable for simple test cases. A coupled drop impact test case corresponds with equivalent experiments until the drop detachment. The acoustic pressure shows a significant rise in the vicinity of the bubble detachment within both phases. However, an oscillation of the cavity bottom can not be observed in the multiphase neither in the acoustic outputs of the airborne signal.
Downsizing and enhancing broad learning systems by feature augmentation and residuals boosting
Authors: Xie Runshan , Wang Shitong
Published: April 2020

Recently, a broad learning system (BLS) has been theoretically and experimentally confirmed to be an efficient incremental learning system. To get rid of deep architecture, BLS shares the same architecture and learning mechanism of the well-known functional link neural networks (FLNN), but works in broad learning way on both the randomly mapped features of original features of data and their randomly generated enhancement nodes. As such, BLS often requires a huge heap of hidden nodes to achieve the prescribed or satisfactory performance, which may inevitably cause both overwhelming storage requirement and overfitting phenomenon. In this study, a stacked architecture of broad learning systems called D&BLS is proposed to achieve enhanced performance and simultaneously downsize the system architecture. By boosting the residuals between previous and current layers and simultaneously augmenting the original input space with the outputs of the previous layer as the inputs of current layer, D&BLS stacks several lightweight BLS sub-systems to guarantee stronger feature representation capability and better classification/regression performance. Three fast incremental learning algorithms of D&BLS are also developed, without the need for the whole re-training. Experimental results on some popular datasets demonstrate the effectiveness of D&BLS in the sense of both enhanced performance and reduced system architecture.
Characterization of bio-coal briquettes blended from low quality coal and biomass waste treated by Garant® bio-activator and its application for fuel combustion
Authors: Mursito Anggoro Tri , Widodo  , Arifin Danang Nor
Published: April 2020

Experimental research was carried out on the manufacturing of bio-coal briquettes from a blend of two different types of low-quality coal and biomass waste in the absence of coal carbonization, where the third blend of the material was fermented by adding a bio-activator solution before pressurizing the components into briquettes. The coal samples from Caringin–Garut Regency (BB–Garut) had a low calorific value and a high sulfur content (6.57 wt%), whereas the coal samples from Bayah–Lebak Regency (BB–Bayah) had a higher calorific value and a lower sulfur content (0.51 wt%). The biomass added to the coal blend is in the form of fermented cow dung (Bio–Kohe), and it had a calorific value of 4192 kcal/kg and a total sulfur content of 1.56 wt%. The main objective of this study is to determine the total decrease in the sulfur content in a blend of coal and biomass in which a fermentation process was carried out using a bio-activator for 24 h. The used bio-activator was made from Garant® (1:40) + molasses 1 wt%/vol, and its used amount was 0.2 L/kg. Also, the total sulfur content in the blend was 1.00 wt%–1.14 wt%, which fulfills the necessary quality requirements for non-carbonized bio-coal briquettes. The pyritic and sulfate content in the raw coal was dominant, and the organic sulfur, when fermented with Garant®, was found to be less in the produced bio-coal briquettes by 38%–58%.
Explanation of the Colour Change in Alexandrites
Authors: Xie Fei , Cao Yu , Ranchon Cindy , Hart Alan , Hansen Robin , Post Jeffrey E. , Whitney Coralyn W. , Dawson-Tarr Emma , Drew Alan J. , Dunstan David J.
Published: April 2020

Alexandrites are remarkable and rare gemstones. They display an extraordinary colour change according to the ambient lighting, from emerald green in daylight to ruby red in incandescent light from tungsten lamps or candles. While this colour change has been correctly attributed to chromium impurities and their absorption band in the yellow region of the visible light spectrum, no adequate explanation of the mechanism has been given. Here, the alexandrite effect is fully explained by considering the von Kries model of the human colour constancy mechanism. This implies that our colour constancy mechanism is real (objective) and primarily attuned to correct for the colour temperature of black-body illuminants.
Biochemical evolution of dissolved organic matter during snow metamorphism across the ablation season for a glacier on the central Tibetan Plateau
Authors: Feng Lin , An Yanqing , Xu Jianzhong , Li Xiaofei , Jiang Bin , Liao Yuhong
Published: April 2020

The metamorphism of snow (snowmelt process) has a potential influence on chemical and physical process occurring within it. This study carried out a detailed study on the variation of dissolved organic matter (DOM) in different stages of snowmelt in a typical mountain glacier located at Tibetan Plateau through collecting four different surface snow/ice categories, i.e., fresh snow, fine firn, coarse firn, and granular ice during May to October in 2015. The dissolved organic carbon (DOC) was observed by lost 44% from fresh snow to fine firn and enriched 129% from fine firn to granular ice, reflecting the dynamic variability in DOC concentration during snow metamorphism. The absorbance properties of each snow category are positively correlated with DOC concentration. The result of excitation emission matrix fluorescence with parallel factor analysis (EEM-PARAFAC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) highlighted the domination of lipid- and protein-like compounds in glacial-derived DOM. The molecular composition of the DOM also exhibited a new N-containing molecular formula (CHON classes) that was enriched during snow metamorphism. This study suggests that snow metamorphism could induce a loss of DOM as well as enrich and modify the DOM.
Simulation of overland flow considering the influence of topographic depressions
Authors: Hu Lin , Bao Weimin , Shi Peng , Wang Jianjin , Lu Meixia
Published: April 2020

The simulation of overland flow, wherein runoff yield and concentration are influenced by topography, is fundamental to hydrological forecasting. Therefore, critically evaluating the characteristics of overland flow under the influence of topographic depressions—which are one of the most common microtopographic structures—is vital for improving current hydrological models. In this study, we developed a solution for the real-world application of overland flow simulations under the influence of depressions in hydrological models. A relative depression storage–outflow curve (RDOC) was proposed to investigate surface outflow processes. Experiments were conducted based on the variable-controlling approach using three rainfall return periods, four slopes, and four depression rates while ensuring a consistent initial soil moisture content. A homogenized RDOC was achieved based on shape analysis; it was parameterized by the outflow threshold and the reciprocal of the curve index of two outflow stages (B and D). A relative depression storage–outflow function (RDOF) was generated and a complete calculation procedure was applied within a hydrological model. Furthermore, we analyzed the hydrological responses to parameters of different hydrological factors to improve our understanding of the parameter determination of the RDOF.
An uncommon use of irradiated flavins: Brønsted acid catalysis
Authors: Arakawa Yukihiro , Mihara Tomohiro , Fujii Hiroki , Minagawa Keiji , Imada Yasushi
Published: April 2020

Visible light irradiation to flavins in the presence of thiols and O2 provides Brønsted acidic species that can be used as efficient catalysts for thioacetalizations and for Mannich-type reactions under non-irradiation and mild conditions.
Face-selective adsorption of a prochiral compound on the chiral pore-surface of a metal–macrocycle framework (MMF) directed towards stereoselective reactions
Authors: Tashiro Shohei , Umeki Tsutomu , Kubota Ryou , Shionoya Mitsuhiko
Published: April 2020

The chiral pore-surface of a porous metal–macrocycle framework face-selectively adsorbs a prochiral molecule with the aid of a supramolecular chiral auxiliary.
Enzymatic deposition of PPy onto cPEG-grafted silk fibroin membrane to achieve conductivity
Authors: Yuan Jingjing , Wang Lin , Xu Bo , Wang Ping , Yuan Jiugang , Yu Yuanyuan , Deng Chao , Wang Qiang
Published: April 2020

Laccase-mediatedgraftpolymerization of polypyrrole (PPy) onto the SF-g-cPEG membrane was performed to achieve electrical conductivity.
β-C(sp2)–H alkylation of enamides using xanthate chemistry
Authors: Bertho Sylvain , Dondasse Ismaël , Retailleau Pascal , Nicolas Cyril , Gillaizeau Isabelle
Published: April 2020

Access to the γ-amino-β,γ-unsaturated acyl scaffold was established by applying xanthate chemistry to enamides.
Synthesis, modular composition, and electrochemical properties of lamellar iron sulfides
Authors: Horwitz Noah E. , Shevchenko Elena V. , Park Jehee , Lee Eungje , Xie Jiaze , Chen Baorui , Zhong Yu , Filatov Alexander S. , Anderson John S.
Published: April 2020

A new class of layered iron sulfide materials offers tunable composition and properties for electrochemical energy storage.
Exploring the impact of atomic lattice deformation on oxygen evolution reactions based on a sub-5 nm pure face-centred cubic high-entropy alloy electrocatalyst
Authors: Huang Kang , Zhang Bowei , Wu Junsheng , Zhang Tianyuan , Peng Dongdong , Cao Xun , Zhang Zhan , Li Zhong , Huang Yizhong
Published: April 2020

Multimetal high-entropy alloys (HEAs) have been recognized as potential catalysts that can possibly replace the conventional metal oxides and noble metals for use in energy conversion and water splitting such as oxygen evolution reactions (OERs).
Design principles and fundamental understanding of biosensors for amyloid-β detection
Authors: Zhang Yanxian , Ren Baiping , Zhang Dong , Liu Yonglan , Zhang Mingzhen , Zhao Chao , Zheng Jie
Published: April 2020

Aβ as biomarker in Alzheimer’s disease (AD) drives the significant research efforts for developing different biosensors with different sensing strategies, materials, and mechanisms for Aβ detection.
Functional characterization of human brown adipose tissue metabolism
Authors: Richard Marie Anne , Pallubinsky Hannah , Blondin Denis P.
Published: April 2020

Brown adipose tissue (BAT) has long been described according to its histological features as a multilocular, lipid-containing tissue, light brown in color, that is also responsive to the cold and found especially in hibernating mammals and human infants. Its presence in both hibernators and human infants, combined with its function as a heat-generating organ, raised many questions about its role in humans. Early characterizations of the tissue in humans focused on its progressive atrophy with age and its apparent importance for cold-exposed workers. However, the use of positron emission tomography (PET) with the glucose tracer [18F]fluorodeoxyglucose ([18F]FDG) made it possible to begin characterizing the possible function of BAT in adult humans, and whether it could play a role in the prevention or treatment of obesity and type 2 diabetes (T2D). This review focuses on the in vivo functional characterization of human BAT, the methodological approaches applied to examine these features and addresses critical gaps that remain in moving the field forward. Specifically, we describe the anatomical and biomolecular features of human BAT, the modalities and applications of non-invasive tools such as PET and magnetic resonance imaging coupled with spectroscopy (MRI/MRS) to study BAT morphology and function in vivo, and finally describe the functional characteristics of human BAT that have only been possible through the development and application of such tools.
Structure of a tRNA-specific deaminase with compromised deamination activity
Authors: Liu Huijuan , Wu Saibin , Ran Dewei , Xie Wei
Published: April 2020

Nucleotide 34 in tRNA is extensively modified to ensure translational fidelity and efficacy in cells. The deamination of adenosine at this site catalyzed by the enzyme TadA gives rise to inosine (I), which serves as a typical example of the wobble hypothesis due to its diverse basepairing capability. However, recent studies have shown that tRNAArgACG in Mycoplasma capricolum contains unmodified adenosine, in order to decode the CGG codon. The structural basis behind the poorly performing enzyme M. capricolum TadA (McTadA) is largely unclear. Here we present the structures of the WT and a mutant form of McTadA determined at high resolutions. Through structural comparison between McTadA and other active TadA enzymes as well as modeling efforts, we found that McTadA presents multiple structural conflicts with RNA substrates and thus offered support to previous studies from a structural perspective. These clashes would potentially lead to reduced substrate binding affinity of McTadA, consistent with our in vitro deamination activity and binding assays. To rescue the deamination activity of McTadA, we carried out two rounds of protein engineering through structure-guided design. The unsuccessful attempts of the activity restoration could be attributed to the altered dimer interface and stereo hindrance from the non-catalytic subunit of McTadA, which could be the inevitable outcome of the natural evolution. Our study provides structural insight into an alternative decoding and evolutionary strategy by a compromised TadA enzyme at a molecular level.
Mammals diversity of mount sawal wildlife reserve, Ciamis, West Jawa
Authors: Sulistyadi Eko
Published: April 2020

We conducted research on mammals diversity in the Mount Sawal Wildlife Reserve on March 2012. Data collection was obtained by direct observation and interviews. They are includes direct encounters, traces/signs of the mammals presence (ex: faeces, traces/footprints, odors, scratch marks, food scraps, etc.) as well as information from the community around the forest. Observations were carried out in seven observation path/forest block in Mount Sawal namely Belandongan, Cibaruyan Jero, Gintung, Gunung Luhur, Kigugula, Jamikuwu, and Sawah Gunung. We documented at least 10 species of mammals have been recorded, including Panthera pardus melas, Presbytis comata, Trachypithecus auratus, Macaca fascicularis, Muntiacus muntjak, Hystrix javanica, Aonyx cinereus, Prionailurus bengalensis, Mydaus javanensis, and Sus Scrofa. The existence of mammals is relatively evenly distributed in all observation path/forest block in The Sawal Mountain. Six species are protected by Indonesian Law, including Panthera pardus melas, Presbytis comata, Trachypithecus auratus, Muntiacus muntjak, Hystrix javanica, and Prionailurus bengalensis. Information on the diversity of mammals is expected to be a scientific consideration in the management area of the Mount Sawal Wildlife Reserve.
Arzt-Bewertungsportale – Tipps und Tricks
Authors: Koch U.
Published: April 2020

Wenn die ärztliche Tätigkeit und alle sonstigen Eigenschaften der eigenen Behandlungseinrichtung öffentlich im Internet bewertet werden, empfinden viele Ärzte dies als unbequem, ehrenrührig oder sehen gar ein Risiko für den wirtschaftlichen Erfolg. Die Rechtsprechung in Deutschland ist eindeutig: Es gibt keine Vermeidungsstrategie. Dieser Beitrag führt einige Handlungsoptionen für Ärzte auf, die sich aktiv mit Online-Bewertungen auseinandersetzen wollen und bewertet diese Optionen anhand eigener Erfahrungen des Autors.
Color Stability in Temporization
Authors: Mann Navjot S. , Jhamb Ashu , Bajaj Shikha , Arora Rahul
Published: April 2020

Introduction Provisional restoration refers to a prosthesis which is designed to enhance the esthetic value, or function for a short time, following which it is replaced by using a fixed prosthesis. Color stability is very important factor to be kept in mind during selection of provisional materials in aesthetically important areas. Although there are various studies which look into the issue of stability of color of provisional restorations, the results are contradictory and confusing. This study was planned to compare the color stability of commonly used provisional restorative materials after exposing them to various kinds of discolorants.

Materials and Methods This work evaluated the effect of five common beverages, including tea, on color changes of different provisional materials: 1) Polymethyl methacrylates (DPI); 2) Bisacryl composite (ProtempTM II–3M ESPE); 3) Light polymerized composite (Revotek LC–GC). Color measurement of all specimens was compared with the original values of each specimen prior to immersion.

Results Within the limitations of this study, it was concluded that:

a) There is no difference in color stability of provisional materials.

b) Only food dye produced a clinically appreciable color change, whereas color change by cola and coffee cannot be appreciated by humans and that of tea can be appreciated only by trained eyes.
Reconnection from a turbulence perspective
Authors: Adhikari S. , Shay M. A. , Parashar T. N. , Pyakurel P. Sharma , Matthaeus W. H. , Godzieba D. , Stawarz J. E. , Eastwood J. P. , Dahlin J. T.
Published: April 2020

The spectral properties associated with laminar, anti-parallel reconnection are examined using a 2.5D kinetic particle in cell simulation. Both the reconnection rate and the energy spectrum exhibit three distinct phases: an initiation phase where the reconnection rate grows, a quasi-steady phase, and a declining phase where both the reconnection rate and the energy spectrum decrease. During the steady phase, the energy spectrum exhibits approximately a double power law behavior, with a slope near −5/3 at wave numbers smaller than the inverse ion inertial length and a slope steeper than −8/3 for larger wave numbers up to the inverse electron inertial length. This behavior is consistent with a Kolmogorov energy cascade and implies that laminar reconnection may fundamentally be an energy cascade process. Consistent with this idea is the fact that the reconnection rate exhibits a rough correlation with the energy spectrum at wave numbers near the inverse ion inertial length. The 2D spectrum is strongly anisotropic with most energy associated with the wave vector direction normal to the current sheet. Reconnection acts to isotropize the energy spectrum, reducing the Shebalin angle from an initial value of 70° to about 48° (nearly isotropic) by the end of the simulation. The distribution of energy over length scales is further analyzed by dividing the domain into spatial subregions and employing structure functions.
Design, fabricate, and experimental verification of an ultrasonic linear motor derived from V-type motors
Authors: Wang Yingzhi , Wang Liming
Published: April 2020

In this work, a novel ultrasonic linear motor is proposed. The proposed motor has two driving feet and a simple structure. The torque applied to the motor is converted into a normal preload between the driving feet and the mover, avoiding the use of a large preloading mechanism. The vibration characteristics of the motor are studied by the finite element analysis method. Finally, the prototype is fabricated. The experimental system is established, and a series of experiments has been carried out to evaluate the performance of the motor in terms of maximum velocity and maximum output force, and the feasibility of the proposed motor is verified. The experimental results show that the maximum no-load velocities of the motor moving to the right and left are 85.2 mm/s and 76 mm/s, respectively, and the maximum output force is 1.96 N. The numerical simulation results show that the stator of the motor can be used as a displacement amplifying structure, which can effectively amplify one or two orders of magnitude deformation of the piezoelectric stack.
Probabilistic vortex crossing criterion for superconducting nanowire single-photon detectors
Authors: Jahani Saman , Yang Li-Ping , Buganza Tepole Adrián , Bardin Joseph C. , Tang Hong X. , Jacob Zubin
Published: April 2020

Superconducting nanowire single-photon detectors have emerged as a promising technology for quantum metrology from the mid-infrared to ultraviolet frequencies. Despite recent experimental successes, a predictive model to describe the detection event in these detectors is needed to optimize the detection metrics. Here, we propose a probabilistic criterion for single-photon detection based on single-vortex (flux quanta) crossing the width of the nanowire. Our model makes a connection between the dark counts and photon counts near the detection threshold. The finite-difference calculations demonstrate that a change in the bias current distribution as a result of the photon absorption significantly increases the probability of single-vortex crossing even if the vortex potential barrier has not vanished completely. We estimate the instrument response function and show that the timing uncertainty of this vortex tunneling process corresponds to a fundamental limit in timing jitter of the click event. We demonstrate a trade-space between this intrinsic (quantum) timing jitter, quantum efficiency, and dark count rate in TaN, WSi, and NbN superconducting nanowires at different experimental conditions. Our detection model can also explain the experimental observation of exponential decrease in the quantum efficiency of SNSPDs at lower energies. This leads to a pulse-width dependency in the quantum efficiency, and it can be further used as an experimental test to compare across different detection models.
Features of explosion of thin aluminum foils on an 8 kA, 350 ns pulse generator
Authors: Shelkovenko T. A. , Tilikin I. N. , Mingaleev A. R. , Pikuz S. A.
Published: April 2020

This paper presents the results of a study of the explosion of Al foils with a thickness of 4 μm on an 8 kA, 350 ns pulsed-power generator. The features of the energy deposition process in the explosion of foils in comparison with wires of similar mass and cross section, as well as with thin wires, are studied. In the experiments presented here, the dependence of the energy deposition in the foil on its initial structure was found. Two types of exploded foil structure were recorded using point-projection radiography.
Deeply cooled and temperature controlled microjets: Liquid ammonia solutions released into vacuum for analysis by photoelectron spectroscopy
Authors: Buttersack Tillmann , Mason Philip E. , Jungwirth Pavel , Schewe H. Christian , Winter Bernd , Seidel Robert , McMullen Ryan S. , Bradforth Stephen E.
Published: April 2020

A versatile, temperature controlled apparatus is presented, which generates deeply cooled liquid microjets of condensed gases, expelling them via a small aperture into vacuum for use in photoelectron spectroscopy (PES). The functionality of the design is demonstrated by temperature- and concentration-dependent PES measurements of liquid ammonia and solutions of KI and NH4I in liquid ammonia. The experimental setup is not limited to the usage of liquid ammonia solutions solely.
The effect of tensor light shift on residual magnetic field compensation in a nuclear spin co-magnetometer
Authors: Jia Yuchen , Liu Zhanchao , Ding Ming , Chai Zhen , Liang Xiaoyang , Wu Wenfeng
Published: April 2020

In a nuclear spin co-magnetometer, it was found that the probe light parameters have a significant impact on the transverse residual magnetic field compensation. In this paper, we demonstrated that this effect is caused by the tensor light shifts of the linearly polarized probe light. This effect can be suppressed at a certain probe light polarization. We obtained this probe light polarization experimentally and reduced the impact of probe power on magnetic field compensation by 35 times. The impact of probe light frequency is also suppressed. Furthermore, the influence of the pump power, the static magnetic field, and the cell temperature on this optimized polarization was investigated. The tensor light shift can be suppressed at about 17° polarization under different conditions in our system. Moreover, the actual residual magnetic field in the magnetic shields can be obtained, which is useful for the magnetic field design of the co-magnetometer, and this method can also be extended to other atomic devices to suppress the tensor light shift.
Topology of the polarization field in PbTiO3 nanoparticles of different shapes by atomic-level simulations
Authors: Di Rino F. , Sepliarsky M. , Stachiotti M. G.
Published: April 2020

An atomistic model approach parameterized from first-principles calculations is used to investigate size and shape effects on the polarization field in isolated stress-free PbTiO3 nanoparticles. The study was carried out by molecular dynamics simulations in free-standing nanodots of cylindrical, spherical, and ellipsoidal shapes. We show that in cylinders with diameter equal to height, the size-induced transformation from the vortex to the flux-closure domain configuration causes an anomaly in the behavior of the toroidal moment and the volume of the system. During this transformation, the vortex core evolves into domain walls while the resulting structure is stabilized due to the non-homogeneous distribution of polarization and strain inside the domains. A similar behavior is observed in elongated cylinders, spheres, and spheroids. The increment in the diameter/height relation of the nanoparticles gives rise to a succession of topological transformations that include multi-vortex configurations, ferroelectric bubble states, and multi-domain patterns. While the transformation path for flat cylinders is similar to the one previously obtained for cuboids, the thinner edge region of the spheroids prevents the stabilization of one- and two-bubble states. Despite this last difference, our results indicate that the polarization pattern of a nanoparticle depends more on its aspect ratio than on its shape.
Metal halide perovskites for blue light emitting materials
Authors: Luo Menghui , Jiang Yuanzhi , He Tingwei , Yuan Mingjian
Published: April 2020

Metal halide perovskites are considered excellent light emitting materials due to their high photoluminescence quantum yields, tunable spectral wavelength, and outstanding carrier transport properties. By taking advantage of these characteristics, perovskite light-emitting diodes (PeLEDs) can be fabricated via solution processing techniques. PeLEDs, thus, show great promise in display and lighting applications. Accordingly, external quantum efficiencies over 20% have been achieved in green- and red-PeLEDs. However, the performance of blue PeLEDs still lags far behind its red and green analogs. In this review, we summarize the recent progress of blue PeLEDs based on the halogen regulation strategy and the quantum confinement strategy. We discuss the challenges from aspects of poor charge injection, spectral instability, and high defect-states density encountered in blue PeLEDs. We make an outlook on feasible future research directions for highly efficient and stable blue PeLEDs.