bluuebunny/crossref_metadata_2025_split huggingface dataset:
The postnatal development of MT, V1, LGN, pulvinar and SC in prosimian galagos (Otolemur garnettii)
Authors: Turner Emily C. , Gabi Mariana , Liao Chia‐Chi , Kaas Jon H. 
Published: February 2020

AbstractConsiderable evidence supports the premise that the visual system of primates develops hierarchically, with primary visual cortex developing structurally and functionally first, thereby influencing the subsequent development of higher cortical areas. An apparent exception is the higher order middle temporal visual area (MT), which appears to be histologically distinct near the time of birth in marmosets. Here we used a number of histological and immunohistological markers to evaluate the maturation of cortical and subcortical components of the visual system in galagos ranging from newborns to adults. Galagos are representative of the large strepsirrhine branch of primate evolution, and studies of these primates help identify brain features that are broadly similar across primate taxa. The histological results support the view that MT is functional at or near the time of birth, as is primary visual cortex. Likewise, the superior colliculus, dorsal lateral geniculate nucleus, and the posterior nucleus of the pulvinar are well‐developed by birth. Thus, these subcortical structures likely provide visual information directly or indirectly to cortex in newborn galagos. We conclude that MT resembles a primary sensory area by developing early, and that the early development of MT may influence the subsequent development of dorsal stream visual areas.
Complexes H2CO:PXH2and HCO2H : PXH2for X=NC, F, Cl, CN, OH, CCH, CH3, and H: Pnicogen Bonds and Hydrogen Bonds
Authors: Del Bene Janet E. , Alkorta Ibon , Elguero José 
Published: February 2020

AbstractAb initio MP2/aug’‐cc‐pVTZ calculations have been carried out to investigate H2CO : PXH2pnicogen‐bonded complexes and HCO2H : PXH2complexes that are stabilized by pnicogen bonds and hydrogen bonds, with X=NC, F, Cl, CN, OH, CCH, CH3, and H. The binding energies of these complexes exhibit a second‐order dependence on the O−P distance. DFT‐SAPT binding energies correlate linearly with MP2 binding energies. The HCO2H : PXH2complexes are stabilized by both a pnicogen bond and a hydrogen bond, resulting in greater binding energies for the HCO2H : PXH2complexes compared to H2CO : PXH2. Neither the O−P distance across the pnicogen bond nor the O−P distance across the hydrogen bond correlates with the binding energies of these complexes. The nonlinearity of the hydrogen bonds suggests that they are relatively weak bonds, except for complexes in which the substituent X is either CH3or H. The pnicogen bond is the more important stabilizing interaction in the HCO2H : PXH2complexes except when the substituent X is a more electropositive group. EOM‐CCSD spin‐spin coupling constants1pJ(O−P) across pnicogen bonds in H2CO:PXH2and HCO2H : PXH2complexes increase as the O−P distance decreases, and exhibit a second order dependence on that distance. There is no correlation between2hJ(O−P) and the O−P distance across the hydrogen bond in the HCO2H : PXH2complexes.2hJ(O−P) coupling constants for complexes with X=CH3and H have much greater absolute values than anticipated from their O−P distances.
Improvement of the input performance of a three‐phase‐single‐phase matrix converter based on space vector modulation
Authors: Xu Yuxiang , Wang Peiliang , Cai Zhiduan , Jiang Yongfeng 
Published: February 2020

SummaryA 6‐switch three‐phase to single‐phase matrix converter (3‐1MC) with independent neutral line is directly coupled to the input side through bidirectional switches, and the output ripple power produces low‐frequency harmonics in the input side that are difficult to filter out. In this paper, the expressions of the frequencies and contents of the low‐frequency harmonics are derived based on the principle of input‐output instantaneous power conservation. Then, a 3‐1MC topology with decoupling unit is studied and the working principle and process of improving the input performance are analyzed. Second, based on the relationship between the output side and the decoupling side modulation function, the influence of the introduction of the decoupling unit on the maximum voltage transfer ratio of 3‐1MC is studied. The relationship between the voltage transfer ratio and parameters such as decoupling unit and output frequency is derived in detail. It is proved that maximum voltage transfer ratio of the topology is a nonlinear function related to system parameters. Then, the operating principle and modulation method of 3‐1MC are discussed. A double‐side current closed‐loop control strategy based on space vector modulation under power decoupling conditions is proposed. Finally, an experimental platform is built to verify that the 3‐1MC with decoupling unit can suppress the low‐frequency harmonics in the input current at different output frequencies and effectively improve the performance of the input side. The results show that the 3‐1MC with the decoupling unit is beneficial for use in single‐phase applications.
Experimental observation of intermittent route to chaos in magnetized filamentary discharge plasma due to the cylindrical plasma bubble
Authors: Megalingam Mariammal , Sangem Anurag , Sarma Bornali 
Published: February 2020

AbstractWe delineate an experimental observation of the effect of the magnetic field along with mesh grid biasing in the presence of a cylindrical plasma bubble in a filamentary discharge magnetised plasma system. The cylindrical mesh grid of 80% optical transparency has been negatively biased and introduced in the plasma for creating a plasma bubble. Plasma floating potential fluctuations have been taken outside (LP1) and inside (LP2) of the plasma bubble. It has been noticed that as the external magnetic field is increased the oscillation pattern shows intermittent route to chaos as the system evolved from regular type of relaxation oscillations (of larger amplitude) to an irregular type of oscillations (of smaller amplitude) We have used recurrence quantification analysis (RQA) to the observed intermittency to chaos in the plasma. The main measures of RQA are laminarity (LAM) and determinism (DET). The laminarity measure can be associated with the average time between the chaotic burst in the intermittency. It has also been observed that the DET depends on the control parameter and decreases exponentially, features like a dip in skewness and a hump in the kurtosis with the variation of control parameter have been noticed, which are the strong evidence of intermittent behaviour of the system. Further, a numerical model has been developed to the observed experimental analysis of the intermittent route to chaos.
Ecological drivers of African swine fever virus persistence in wild boar populations: Insight for control
Authors: Pepin Kim M. , Golnar Andrew J. , Abdo Zaid , Podgórski Tomasz 
Published: February 2020

AbstractEnvironmental sources of infection can play a primary role in shaping epidemiological dynamics; however, the relative impact of environmental transmission on host‐pathogen systems is rarely estimated. We developed and fit a spatially explicit model of African swine fever virus (ASFV) in wild boar to estimate what proportion of carcass‐based transmission is contributing to the low‐level persistence of ASFV in Eastern European wild boar. Our model was developed based on ecological insight and data from field studies of ASFV and wild boar in Eastern Poland. We predicted that carcass‐based transmission would play a substantial role in persistence, especially in low‐density host populations where contact rates are low. By fitting the model to outbreak data using approximate Bayesian computation, we inferred that between 53% and 66% of transmission events were carcass‐based that is, transmitted through contact of a live host with a contaminated carcass. Model fitting and sensitivity analyses showed that the frequency of carcass‐based transmission increased with decreasing host density, suggesting that management policies should emphasize the removal of carcasses and consider how reductions in host densities may drive carcass‐based transmission. Sensitivity analyses also demonstrated that carcass‐based transmission is necessary for the autonomous persistence of ASFV under realistic parameters. Autonomous persistence through direct transmission alone required high host densities; otherwise re‐introduction of virus periodically was required for persistence when direct transmission probabilities were moderately high. We quantify the relative role of different persistence mechanisms for a low‐prevalence disease using readily collected ecological data and viral surveillance data. Understanding how the frequency of different transmission mechanisms vary across host densities can help identify optimal management strategies across changing ecological conditions.
Influence of process parameters on the energy requirements and dried sliced tomato quality
Authors: Nwakuba Nnaemeka R. , Chukwuezie Osita C. , Asonye Gladys U. , Asoegwu Sabbas N. 
Published: February 2020

AbstractThis study presents the effects of process parameters on the energy demand for drying and quality indices of dried tomato slices. The experiment was designed and analyzed with the Box‐Behnken method of Design Expert and conducted for drying 1800 g batch of a local variety of tomatoes with a solar‐electric dryer. The study examined the impact of varying process parameters: air temperature (50°C, 60°C, and 70°C), sample thicknesses (10, 15, and 20 mm), and air velocities (1.0, 1.5, and 2.0 ms−1) on the total and specific energy requirements, drying time, lycopene content, ascorbic acid, nonenzymatic browning index, brightness, and ratio of redness to yellowness of dried tomato samples, with emphasis on process optimization and drying time. The prediction of the optimal process condition is obtained using the desirability index technique. The results obtained show that the total and specific energy requirements for a batch of tomato varied from 7.82 to 125.48 kJ h and 6.70 to 179.83 kJ h g−1. The results of the analysis of variance (ANOVA) indicate that all the studied process parameters were significant with P > .05; with the maximum (40.21%) and minimum (19.82%) percent energy contribution by air temperature and air velocity, respectively. The energy of activation varies between 20.26 and 39.35 kJ mol−1. At the optimum process conditions of 57.28°C, 14.08 mm, and 1.3 ms−1, the specific energy requirements, lycopene content, ascorbic acid content, nonenzymatic browning index, brightness, redness to yellowness ratio, and drying duration are obtained as 103.313 ± 2.35 kW h kg−1, 58.7 ± 2.19 mg/100 mg dry matter, 2.9 ± 0.26 mg/g, 0.51 ± 0.033 absorbance unit, 60.074 ± 1.44, 0.77 ± 0.021, and 61.88 ± 8.93 minutes, respectively. The results of the study are of immense benefit to the food drying industry, as it provides food industries with improved drying parameters for enhancing dried tomato quality, as well as increasing dryer energy efficiency and cost‐effectiveness. Sugestions on prospects for further studies were given.
Investigation on jet grouting support strategy for controlling time‐dependent deformation in the roadway
Authors: Sun Yuantian , Li Guichen , Zhang Junfei 
Published: February 2020

AbstractThe efficiency of coal mining is seriously affected by roadway stability, as large time‐dependent deformation of roadway frequently occurs and needs to be maintained several times during its service life. Such rheological deformation was common in soft coal mass at Huaibei coalfield in China. To address this issue, in this study, the time‐dependent deformation of the soft coal roadway was analyzed and a new Jet Grouting (JG) technique was presented for controlling deformation. The time‐dependent deformation of the soft coal roadway was numerically simulated and validated. Based on the field test results and the verified model, a JG support model was established to examine its effect on roadway deformation. The JG support system can reduce the horizontal and vertical displacement of the roadway effectively and constrain the time‐dependent deformation of coal mass. The deformation rate and stabilization time of roadway decreased significantly by comparison with conventional support. This work presented a promising JG support scheme for controlling the time‐dependent deformation in the roadway in deep underground mine, which can greatly promote the JG design and application.
Safety assessment of glutaminase from Aspergillus niger
Authors: Vo Trung Duc , Sulaiman Christina , Tafazoli Shahrzad , Lynch Barry , Roberts Ashley , Chikamatsu Go 
Published: February 2020

AbstractGlutaminase (glutamine aminohydrolase EC 3.5.1.2) is used in the production of food ingredients rich in l‐glutamic acid that are added to finished foods for the purpose of enhancing or improving the savory flavor profile of food. The glutaminase enzyme preparation evaluated in these studies, designated as Sumizyme GT hereafter, is obtained by fermentation of Aspergillus niger strain GT147. The safety of Sumizyme GT was evaluated in a series of standard toxicological studies, including a 90‐day oral toxicity study in rats, an in vitro bacterial reverse mutation assay, an in vitro mammalian chromosome aberration test, and an in vivo alkaline Comet assay. Sumizyme GT was not mutagenic or genotoxic, and administration of the enzyme by gavage at doses up to 2,570 mg total organic solids (TOS)/kg body weight (bw) per day for 90 days was without any systemic toxicity. The no‐observed‐adverse‐effect level was concluded to be 2,570 mg TOS/kg bw per day, the highest dose tested. Considering that A. niger has an established history of safe use in the food industry and its safety in the production of food ingredients and food enzymes is well documented, the results of these studies provide further support of the safety of glutaminase from A. niger when used in food production.
Optimization in continuous phase‐transition extraction of crude flavonoids from finger citron fruit and evaluation on their antiaging activities
Authors: Chen Haiqiang , Wang Jing , Liu Xiaojuan , Zhou Aimei , Xiao Jie , Huang Kaixin , Chen Hanmin , Cao Yong 
Published: February 2020

AbstractThe development of antiaging functional products is a hot topic in the field of functional foods. However, the efficient extraction of functional ingredients is the limiting step for the functional food industry. Continuous phase‐transition extraction (CPE) is a new extraction technique that combines the advantages of Soxhlet extraction and supercritical extraction, which may have a distinct advantage over traditional methods in the extraction of flavonoids. In our study, the Box–Behnken design combined with response surface methodology was used to optimize CPE of crude flavonoids from finger citron fruit. The antiaging activities of finger citron crude flavonoids (FCCF) were evaluated by Caenorhabditis elegans (C. elegans) model. The optimal extraction conditions for CPE were as follows: ethanol concentration 85%, temperature 90°C, time 120 min, and pressure 0.2 MPa. Compared with the heat reflux extraction, the extraction rate and content of FCCF extracted by CPE increased by 24.28% and 33.22% (p < .05), respectively. FCCF extended the lifespan of C. elegans by 14.94% without causing adverse effects on their reproduction and locomotion ability. A further analysis suggested that FCCF prolonged the lifespan of nematodes under normal and oxidative stress by increasing the activity of major enzymes in endogenous antioxidant defense system and reducing the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA). The results confirmed the effectiveness of CPE in extracting crude flavonoids from finger citron fruit, and the extracted FCCF exhibited strong antiaging activities.
Determination of the creep behavior of potato tubers during storage period by means of uniaxial and triaxial creep tests
Authors: Shahgholi Gholamhossein , Latifi Meysam , Imani Behrooz , Farrokhi Niusha 
Published: February 2020

AbstractThe analysis of static forces is essential in the storage of agricultural products because these forces are applied in fruits, vegetables, or grains that can lead to their permanent deformation. This mechanical damage increases the product waste. Given that the potato tuber is surrounded by other tubers in the storage, then every tuber is pressurized from all sides or so‐called triaxial stress. To measure the deformation of the specimens, a device was developed to conduct uniaxial and triaxial creep tests on the viscoelastic agricultural products (e.g., potatoes). Accordingly, the creep experiments were performed on potato samples for 5, 30, 60, 120, 240, 360, 420, and 480 min under the constant load of 72.5 N at 3 and 11 replications via uniaxial and triaxial tests, respectively. The results showed that in the creep test, the loading time was significant on the deformation of the specimens at the 0.05 level of probability. Triaxial test showed that the tuber deformation and strain of top layer were more than the middle and bottom layers. The results showed that the deformation of tubers under uniaxial test was more than triaxial one.
DNA methylation: A mechanism for sustained alteration of KIR4.1 expression following central nervous system insult
Authors: Boni Jessica L. , Kahanovitch Uri , Nwaobi Sinifunanya E. , Floyd Candace L. , Olsen Michelle L. 
Published: February 2020

AbstractKir4.1, a glial‐specific inwardly rectifying potassium channel, is implicated in astrocytic maintenance of K+ homeostasis. Underscoring the role of Kir4.1 in central nervous system (CNS) functioning, genetic mutations in KCNJ10, the gene which encodes Kir4.1, causes seizures, ataxia and developmental disability in humans. Kir4.1 protein and mRNA loss are consistently observed in CNS injury and neurological diseases linked to hyperexcitability and neuronal dysfunction, leading to the notion that Kir4.1 represents an attractive therapeutic target. Despite this, little is understood regarding the mechanisms that underpin this downregulation. Previous work by our lab revealed that DNA hypomethylation of the Kcnj10 gene functions to regulate mRNA levels during astrocyte maturation whereas hypermethylation in vitro led to decreased promoter activity. In the present study, we utilized two vastly different injury models with known acute and chronic loss of Kir4.1 protein and mRNA to evaluate the methylation status of Kcnj10 as a candidate molecular mechanism for reduced transcription and subsequent protein loss. Examining whole hippocampal tissue and isolated astrocytes, in a lithium‐pilocarpine model of epilepsy, we consistently identified hypermethylation of CpG island two, which resides in the large intronic region spanning the Kcnj10 gene. Strikingly similar results were observed using the second injury paradigm, a fifth cervical (C5) vertebral hemi‐contusion model of spinal cord injury. Our previous work indicates the same gene region is significantly hypomethylated when transcription increases during astrocyte maturation. Our results suggest that DNA methylation can bidirectionally modulate Kcnj10 transcription and may represent a targetable molecular mechanism for the restoring astroglial Kir4.1 expression following CNS insult.
Precision (Mis)Education
Authors: Matthews Lucas J. 
Published: February 2020

AbstractIn August of 2018, the results of the largest genomic investigation in human history were published. Scanning the DNA of over one million participants, a genome‐wide association study was conducted to identify genetic variants associated with the number of years of education a person has completed. This measure, called “educational attainment,” is often treated as a proxy for intelligence and cognitive ability. The study raises a host of hard philosophical questions about study design and strength of evidence. It also sets the basis for something far more controversial. Using a new genomic method that generates “polygenic scores,” researchers are now able to use the results of the study to predict a person's educational potential from a blood or saliva sample. Going a step further, some researchers have begun to promote “precision education,” which would tailor students’ school plans to their genetic profiles. The idea of precision education provokes concerns about stigma and self‐fulfilling prophecies.
Pediatric Drug Labeling and Imperfect Information
Authors: Wilfond Benjamin S. 
Published: February 2020

AbstractI first became aware of bioethics in the spring of 1980. I had spent a thirty‐six‐hour shift shadowing a medical resident, and I was struck that many of the resident's decisions had ethical dimensions. The next day, I came across the Hastings Center Report, and I realized I wanted to explore ethical issues I found implicit in clinical care, even though I still wanted to become a pediatrician. In September 2019, when I attended my first meeting of the U.S. Food and Drug Administration's Pediatric Advisory Committee, as a pediatric pulmonologist, I had the same sense of awe and curiosity that I had forty years ago. What had appeared initially as somewhat technical decisions about the regulation of drug labeling was suffused with ethical questions. The committee was asked to discuss possible changes to the labeling of two previously approved drugs.
Synthesis and Incorporation of k2U into RNA
Authors: Nainyte Milda , Carell Thomas 
Published: February 2020

AbstractLysidine (k2C) is one of the most modified pyrimidine RNA bases. It is a cytidine nucleoside, in which the 2‐oxo functionality of the heterocycle is replaced by the ϵ‐amino group of the amino acid lysine. As such, lysidine is an amino acid‐containing RNA nucleoside that combines directly genotype (C‐base) with phenotype (lysine amino acid). This makes the compound particularly important in the context of theories about the origin of life and here especially for theories that target the origin of translation. Here, we report the total synthesis of the U‐derivative of lysidine (k2U), which should have the same base pairing characteristics as k2C if it exists in the isoC‐like tautomeric form. To investigate this question, we developed a phosphoramidite building block for k2U, which allows its incorporation into RNA strands. Within RNA, k2U can base pair with the counter base U and isoG, confirming that k2U prefers an isoC‐like tautomeric structure that is also known to dominate for k2C. The successful synthesis of a k2U phosphoramidite and its use for RNA synthesis now paves the way for the preparation of a k2C phosphoramidite and RNA strands containing k2C.
Photoredox‐Mediated Net‐Neutral Radical/Polar Crossover Reactions
Authors: Wiles Rebecca J. , Molander Gary A. 
Published: February 2020

AbstractRadical/Polar Crossover (RPC) chemistry is a rapidly growing subset of photoredox catalysis that is characterized by transformations featuring both radical and ionic modes of reactivity. Net‐neutral RPC is particularly interesting in that both the single‐electron oxidation and reduction steps occur through interaction with the photocatalyst, thus precluding the need for exogenous oxidants or reductants. As such, these transformations facilitate rapid incorporation of molecular complexity while maintaining mild reaction conditions. This review covers recent advances in photoredox‐mediated net‐neutral RPC synthetic methods, with a particular emphasis on C–C bond‐forming reactions.