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Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range synergistic action is involved in substrate recognition and fidelity, and it may also regulate PKA's association with regulatory subunits and other binding partners. To date, a complete understanding of this intramolecular mechanism is still lacking. Here, we integrated NMR(Nuclear Magnetic Resonance)-restrained molecular dynamics simulations and a Markov State Model to characterize the free energy landscape and conformational transitions of PKA-C. We found that the apoenzyme populates a broad free energy basin featuring a conformational ensemble of the active state of PKA-C (ground state) and other basins with lower populations (excited states). The first excited state corresponds to a previously characterized inactive state of PKA-C with the aC helix swinging outward. The second excited state displays a disrupted hydrophobic packing around the regulatory (R) spine, with a flipped configuration of the F100 and F102 residues at the αC-β4 loop. We validated the second excited state by analyzing the F100A mutant of PKA-C, assessing its structural response to ATP and substrate binding. While PKA-CF100A preserves its catalytic efficiency with Kemptide, this mutation rearranges the αC-β4 loop conformation, interrupting the coupling of the two lobes and abolishing the allosteric binding cooperativity. The highly conserved αC-β4 loop emerges as a pivotal element to control the synergistic binding of nucleotide and substrate, explaining how mutations or insertions near or within this motif affect the function and drug sensitivity in homologous kinases. [ABSTRACT FROM AUTHOR]

Currently, work-family conflict of college teachers is a common issue, especially when their children are in the preschool stage, which will directly affect the children’s problem behaviors. This study aims to explore the relationship between parental work-family conflict and children’s problem behaviors, and the mediating role of parental phubbing and children’s problematic media use among Chinese college teachers. A total of 234 college teachers and their preschool children (Meanage= 60.29 months) participated in this study. The results indicate that (1) there is a significant positive correlation between college teachers’ work-family conflict and their children’s problem behaviors; (2) there is a significant mediating effect of problematic media use between work-family conflict and preschool children’s problem behaviors; and (3) Parental phubbing and children’s problematic media use play a chain mediating role between work-family conflict and children’s problem behaviors. The results reveal the influencing mechanism of work-family conflict on preschool children’s problem behaviors. [ABSTRACT FROM AUTHOR]

The pseudokinase (PK) RNase L is a functional ribonuclease and plays important roles in human innate immunity. The ribonuclease activity of RNase L can be regulated by the kinase inhibitor sunitinib. The combined use of oncolytic virus and sunitinib has been shown to exert synergistic effects in anticancer therapy. In this study, we aimed to uncover the mechanism of action through which sunitinib inhibits RNase L. We solved the crystal structures of RNase L in complex with sunitinib and its analogs toceranib and SU11652. Our results showed that sunitinib bound to the ATP-binding pocket of RNase L. Unexpectedly, the aA helix linking the ankyrin repeat-domain and the PK domain affected the binding mode of sunitinib and resulted in an unusual flipped orientation relative to other structures in PDB. Molecular dynamics simulations and dynamic light scattering results support that the binding of sunitinib in the PK domain destabilized the dimer conformation of RNase L and allosterically inhibited its ribonuclease activity. Our study suggested that dimer destabilization could be an effective strategy for the discovery of RNase L inhibitors and that targeting the ATP-binding pocket in the PK domain of RNase L was an efficient approach for modulating its ribonuclease activity. [ABSTRACT FROM AUTHOR]

Molecular dynamics and free energy simulations have been carried out to elucidate the structural origin of differential proteinprotein interactions between the common receptor protein angiotensin converting enzyme 2 (ACE2) and the receptor binding domains of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [A. E. Gorbalenya et al., Nat. Microbiol. 5, 536-544 (2020)] that causes coronavirus disease 2019 (COVID-19) [P. Zhou et al., Nature 579,270-273 (2020)] and the SARS coronavirus in the 2002-2003 (SARS-CoV) [T. Kuiken et al., Lancet 362, 263-270 (2003)] outbreak. Analysis of the dynamic trajectories reveals that the binding interface consists of a primarily hydrophobic region and a delicate hydrogen-bonding network in the 2019 novel coronavirus. A key mutation from a hydrophobic residue in the SARS-CoV sequence to Lys417 in SARS-CoV-2 creates a salt bridge across the central hydrophobic contact region, which along with polar residue mutations results in greater electrostatic complementarity than that of the SARS-CoV complex. Furthermore, both electrostatic effects and enhanced hydrophobic packing due to removal of four out of five proline residues in a short 12-residue loop lead to conformation shift toward a more tilted binding groove in the complex in comparison with the SARS-CoV complex. On the other hand, hydrophobic contacts in the complex of the SARS-CoV-neutralizing antibody 80R are disrupted in the SARS-CoV-2 homology complex model, which is attributed to failure of recognition of SARS-CoV-2 by 80R. [ABSTRACT FROM AUTHOR]

In this work, we propose a new positron annihilation lifetime spectrum measuring method for pulsed positrons. The spatially arranged positron burst detection system is based on a state-of-the-art calcium-doped LYSO crystal and silicon photomultiplier array, with readout by a multichannel fast waveform digitizing DRS4 chip; this system simultaneously provides high detection efficiency and decent timing resolution. The positron burst generation signal serves as the starting trigger and the timing signal of all the detector channels is the stopping signal, so that the time spread distribution is the lifetime spectrum. The current system has 2048-channel modularized crystals coupled to 2048-channel 3 × 3 mm² silicon photomultipliers. All analog signals from the detectors are digitized separately before implementing digital constant fraction discrimination by a field-programmable gate array. The performance of the single-channel detector was investigated and optimized by improving the silicon photomultiplier readout electronics and the light collection of the scintillator. Preliminary results showed that the best coincidence timing resolution by two identical, 5 mm long, single LYSO detectors was 84 ps and that the measurement was double the 511 keV coincidence of a 22Na source. [ABSTRACT FROM AUTHOR]

We have developed a space distribution method for intense sub-nanosecond or even picosecond positron burst detection using a detector array. In this method, piled signals will be generated when more than one photon of the burst is captured by the same detector cell. The way of setting energy threshold of 511 keV could eliminate most of piled signals, but the counts of piled signals that have lower energy than the threshold are not affected. In this paper, a Geant4 model is built to investigate the dependence of these low-energy piled signals counts on scintillator materials, as well as the size of the detector. The results can provide theoretical support for designing suitable array detectors in practice. [ABSTRACT FROM AUTHOR]

Macrophages and their initiation of acute inflammation have been defined to be functionally important in tissue repair and regeneration. In injury-induced production of macrophage migration inhibitory factor (MIF), which has been described as a pleiotropic protein that participates in multiple cellular and biologic processes, it is unknown whether it is involved in the regulation of macrophage events during the epimorphic regeneration. In the model of gecko tail amputation, the protein levels of gecko MIF (gMIF) have been determined to be significantly increased in the nerve cells of the spinal cord in association with the recruitment of macrophages to the lesion site. gMIF has been shown to interact with the CD74 receptor to promote the migration of macrophages through activation of Ras homolog gene family member A and to trigger inflammatory responses through MAPK signaling pathways. The determination of microsphere phagocytosis also indicated that gMIF could enhance macrophage phagocytosis. gMIF-mediated recruitment and activation of macrophages have been found to be necessary for gecko tail regeneration, as evidenced by the depletion of macrophages using clodronate liposomes. The results present a novel function of MIF during the epimorphic regeneration, which is beneficial for insights into its pleiotropic property. [ABSTRACT FROM AUTHOR]

With power level of grid-connected converters rising, the switching frequency of the switching devices is commonly greatly reduced to improve its power capacity. However, this results in serious couplings of the dq current components, which leads to degradation of the static and dynamic performances of grid-connected converters and fluctuations of the reactive power in dynamic processes. In this paper, complex vector models under low switching frequency are established for an L/LCL grid-connected converter, and the relationship between the switching frequency and the coupling degree is analyzed. In addition, a series decoupling current control strategy is put forward. It is shown that the proposed control strategy can eliminate the couplings, improve the performances and have good robustness to parameter variations through static and dynamic characteristics analyses and a sensitivity analysis. Experimental and simulation results also verify the correctness of the theoretical analyses and the superiority of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Multi-component non-stationary vibration signals produced at local gear fault can easily be covered by periodic harmonic signal and strong background noise, thus causing difficulty in selecting gear fault features and diagnosing fault state. To address this issue, a gear fault diagnosis method based on variational mode decomposition (VMD) and envelope spectrum was proposed in this study, which was then employed to select gear-fault features from multi-component vibration signals adaptively, extract fault characteristic frequency, and determine health conditions of the gear. Based on VMD of gear-fault vibration signals in complicated environments, the relationship between center frequency at decomposed intrinsic mode functions (IMFs) and the gear mesh frequency was discussed. The technique used to determine the number of decomposed modes and gear-fault characteristic component was also analyzed. On this basis, the gear fault state was disclosed. The proposed approach was validated by fault simulation and experimental data. Results demonstrate that the number of decomposed modes can influence VMD and the selection of fault characteristic component. The center frequency of IMFs obtained from VMD is compared with the gear mesh frequency. When the difference is lower than a certain threshold, the corresponding IMF is the gear-fault characteristic component, and the number of decomposed modes is simultaneously determined. The fault characteristic frequency is extracted from Hilbert envelope demodulation of characteristic component, which is used to determine the gear fault state. Conclusions obtained in this study can provide important references for the VMD method to facilitate effective selection of fault characteristic components during gear fault diagnosis and offer new insights into this type of diagnosis. [ABSTRACT FROM AUTHOR]

In this paper, we present a simple near-field probe model that is composed of an elongated ellipsoid and a finite metal truncated cone. The elongated ellipsoid has been shown to act as a protrusion or separate particle near a truncated cone apex with strong near-field enhancement under laser excitation. By controllably varying the length of the ellipsoid protrusion from the truncated cone, the truncated cone-ellipsoid probes can be adapted to the suitability of near-field probes. The effects of substrate material and excitation wavelength on the near field enhancement for different tip apexes are also discussed. In addition, we compared the properties of the truncated cone-ellipsoid probe with the widely used hemisphere conical tip by launching surface plasmon polaritons on plasmonic waveguides to prove the suitability of the truncated cone-ellipsoid probes as high performance near-field probes. The present simple model would provide a theoretical basis for the actual construction of probes. [ABSTRACT FROM AUTHOR]

The DC bus voltage of the voltage source converter (VSC) is prone to large uctuation and even to losing its stability for the large mutation of grid voltage or DC-link loads. First the characteristics of two-step transmission to power in the VSC are analyzed, proving that it is inevitable for DC bus voltage uctuation to occur when grid voltage or DC-link loads mutate. A new two-step feedforward control strategy is then put forward for curbing the uctuation, which overcomes the shortcoming by which the traditional feedforward control strategy is affected for the performance of current control. The small signal models of nonfeedforward control, traditional feedforward control, and two-step feedforward control are established respectively for comparing their performance. It is certified that the two-step feedforward control maximizes the stability of the bus voltage without affecting current control. Finally, the experimental results verify the correctness of the new strategy and the theoretical analysis. [ABSTRACT FROM AUTHOR]

With some of the intermittent new energy and large nonlinear loads, grid voltage unbalance, harmonics, and frequency deviation are increasing year by year. The voltage source converter (VSC) is seriously affected by the various unexpected factors, and the presence of grid impedance makes the situation worse. In order to make the VSC track the nonideal grid quickly and accurately, this paper proposes a frequency-adaptive grid-virtual- ux synchronization by multiple second-order generalized integrators (MSOGI-GVFS). Key expressions of the MSOGI-GVFS and its frequency response characteristics are described in this paper. A second-order generalized integrator configured as a quadrature signal generator generates a specific-frequency virtual flux. A harmonics decoupling network achieves fundamental and harmonic components of the virtual flux. The positive- and negative-sequence components are separated by multiple positive- and negative-sequence calculators. A frequency-locked loop is used to track the grid angular frequency. Finally, after compensating the voltage and the flux on the grid impedance and the filtering inductor, it accurately achieves the estimation of the grid virtual flux in the highly polluted grid environment. This method may reduce the voltage sensors, eliminate the influence of grid impedance, and track the grid frequency quickly, which contributes to the stability of the VSC. The good performance of MSOGI-GVFS is verified by simulation and experimental results. [ABSTRACT FROM AUTHOR]

Background/objectives Induced pluripotent stem cells (iPS) exhibit enhanced survival and proliferation in ischemic tissues. However, the therapeutic application of iPS cells is limited by their tumorigenic potential. We hypothesized that iPS cells can transmit cytoprotective signals to cardiomyocytes via exosomes/microvesicles. Methods Exosomes/microvesicles secreted from mouse cardiac fibroblast (CF)-derived iPS cells (iPS-exo) were purified from conditioned medium and confirmed by electron micrograph, size distribution and zeta potential by particle tracking analyzer and protein expression of the exosome markers CD63 and Tsg101. Results We observed that exosomes are at low zeta potential, and easily aggregate. Temperature affects zeta potential (- 14 to - 15 mV at 23 °C vs - 24 mV at 37 °C). The uptake of iPS-exo protects H9C2 cells against H2O2-induced oxidative stress by inhibiting caspase 3/7 activation (P < 0.05, n = 6). Importantly, iPS-exo treatment can protect against myocardial ischemia/reperfusion (MIR) injury via intramyocardial injection into mouse ischemic myocardium before reperfusion. Furthermore, iPS-exo deliver cardioprotective miRNAs, including nanog-regulated miR-21 and HIF-1a-regulated miR-210, to H9C2 cardiomyocytes in vitro. Conclusions Exosomes/microvesicles secreted by iPS cells are very effective at transmitting cytoprotective signals to cardiomyocytes in the setting of MIR. iPS-exo thus represents novel biological nanoparticles that offer the benefits of iPS cell therapy without the risk of tumorigenicity and can potentially serve as an "off-the-shelf" therapy to rescue ischemic cardiomyocytes in conditions such as MIR. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is the leading cause of blindness in the working population worldwide, with few effective drugs available for its treatment in the early stages. The Zhujing pill (ZJP) is well-established to enhance the early symptoms of DR, but the mechanism underlying its therapeutic effect remains unclear. In the present study, we used systems biology and multidirectional pharmacology to screen the main active ingredients of ZJP and retrieved DrugBank and Genecards databases to obtain 'drug-disease' common targets. Using bioinformatics analysis, we obtained the core targets, and potential mechanisms of action of ZJP and itsmain components for the treatment of DR.Molecular docking was used to predict the binding sites and the binding affinity of the main active ingredients to the core targets. The predicted mechanism was verified in animal experiments. We found that the main active ingredient of ZJP was oleanolic acid, and 63 common 'drug-disease' targets were identified. Topological analysis and cluster analysis based on the protein-protein interaction network of the Metascape database screened the core targets as PRKCA, etc. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that these core targets were significantly enriched in the pro-angiogenic pathway of the VEGF signaling pathway. Molecular docking and surface plasmon resonance revealed that ZJP and its main active component, oleanolic acid had the highest binding affinity with PKC-a, the core target of the VEGF signaling pathway. Animal experiments validated that ZJP and oleanolic acid could improve DR. [ABSTRACT FROM AUTHOR]

The resonance characteristics of a two-span continuous beam traversed by moving high speed trains at a constant velocity is investigated, in which the continuous beam has uniform span length. Each span of the continuous beam is modeled as a Bernoulli-Euler beam and the moving trains are represented as a series of two degrees-of-freedom mass-spring-damper systems at the axle locations. A method of modal analysis is proposed in this paper to investigate the vibration of two-span continuous beam. The effects of different influencing parameters, such as the velocities of moving trains, the damping ratios and the span lengths of the beam, on the dynamic response of the continuous beam are examined. The two-span continuous beam has two critical velocities causing two resonance responses, which is different from simple supported beam. The resonance condition of the two-span continuous beam is put forward which depends on the first and second natural frequency of the beam and the moving velocity. [ABSTRACT FROM AUTHOR]

Objective: Major depressive disorder is a heterogeneous illness with a mostly uncharacterized pathology. Recent gene array attempts to identify the molecular underpinnings of the illness in human postmortem subjects have not yielded a consensus. The authors hypothesized that controlling several sources of clinical and technical variability and supporting their analysis with array results from a parallel study in the unpredictable chronic mild stress (UCMS) rodent model of depression would facilitate identification of the molecular pathology of major depression. Method: Large-scale gene expression was monitored in postmortem tissue from the anterior cingulate cortex and amygdala in paired male subjects with familial major depression and matched control subjects without major depression (N=14-16 pairs). Area dissections and analytical approaches were optimized. Results from the major depression group were compared with those from the UCMS study and confirmed by quantitative polymerase chain reaction and Western blot. Gene coexpression network analysis was performed on transcripts with conserved major depression-UCMS effects. Results: Significant and bidirectional predictions of altered gene expression were identified in amygdala between major depression and the UCMS model of depression. These effects were detected at the group level and also identified a sub-group of depressed subjects with a more homogeneous molecular pathology. This phylogenetically conserved "molecular signature" of major depression was reversed by antidepressants in mice, identified two distinct oligodendrocyte and neuronal phenotypes, and participated in highly cohesive and interactive gene co-expression networks. Conclusions: These studies demonstrate that the biological liability to major depression is reflected in a persistent molecular pathology that affects the amygdala, and support the hypothesis of maladaptive changes in this brain region as a putative primary pathology in major depression. [ABSTRACT FROM AUTHOR]

lndividuals with chronic kidney disease (CKD) and/or diabetes mellitus (DM) are at increased risk of cardiovascular events and have elevated externalization of phosphatidylserine (PS; which propagates thrombus formation) in a small subpopulation of platelets. The purpose of this study was to examine the effect of I) removing uremic toxins by hemodialysis on PS externalization in patients with either CKD or CKD and DM and 2) ultrafiltrate (UF) from these individuals on PS externalization in healthy platelets. PS externalization was quantified by a fluorescence-activated cell sorter using annexin V in platelet-rich plasma. PS externalization was elevated threefold in CKD patients and returned to basal values during 3-h hemodialysis. In contrast, it was elevated fivefold in individuals with CKD and DM and was still threefold above control after 3-h treatment. UF significantly increased PS externalization in a small subpopulation of platelets from healthy controls. The effect of UF from individuals with CKD and DM was significantly greater than that from patients with CKD alone, and the responses were partially inhibited by the protein kinase Cδ (PKCδ) inhibitor rottlerin and the 5-hydroxytryptamine (5-HT)2A/2C receptor antagonist ritanserin. The data suggest that uremic toxins present in UF mediate PS externalization in a small subpopulation of platelets, at least in part, via the 5-HT2A/2C receptor and PKCδ and demonstrate that DM further enhances platelet PS externalization in CKD patients undergoing hemodialysis. This may explain, at least in part, the additional increase in vascular damage observed in CKD patients when DM is present. [ABSTRACT FROM AUTHOR]

Advanced glycation end products (AGE) are substantially elevated in individuals with diabetes and/or chronic kidney disease (CKD). These patients are at greatly increased risk of cardiovascular events. The purpose of this study was to investigate the novel hypothesis that AGE elicit externalization of the platelet membrane phospholipid phosphatidylserine (PS). This contributes to hemostasis through propagation of the coagulation cascade leading to thrombus formation. Platelet-rich plasma (PRP) was prepared by differential centrifugation and PS externalization was quantified by a fluorescence-activated cell sorter using annexin V-FITC. Human serum albumin (HSA)-AGE was generated by incubating HSA with glucose for 2, 4, or 6 wk, and total HSA-AGE was assessed by fluorescence intensity. The 2-wk HSA-AGE preparation (0-2 mg/ml) stimulated a concentration-dependent increase in PS externalization in a subpopulation of platelets that was three-fold at 2 mg/ml. In contrast, the 4- and 6-wk preparations were maximal at 0.5 mg/ml and fivefold in magnitude. These effects mirrored the change in total HSA-AGE content of the preparations. The PS response was maximal at 10 m~n and inhibited by the PKC-S inhibitor rottlerin and the serotonin [5-hydroxytryptamine (5-HT)]2A,2C receptor antagonist ritanserin in a dose-dependent manner. Moreover, the 5-HT2A,2C receptor agonist 1,2,5-dimethoxy-4-iodophenyl-2-aminopropane mimicked the effect of HSA- AGE on PS externalization. These data demonstrate, for the first time, that HSA-AGE stimulates PS externalization in a subpopulation of platelets via the 5-HT2A,2C receptor. This may have important consequences for platelet involvement in inflammatory responses and the increased cardiovascular risk observed in individuals with diabetes and/or CKD. [ABSTRACT FROM AUTHOR]

Tartary buckwheat ( Fagopyrum tataricum) is a highly nutritious crop that is widely grown in Asia, but the flour contains a large portion of the hull if it is ground with industrial processing since the hull is very hard to remove as it adheres to the testa layer of the groat. Rice-Tartary, a particular type of Tartary buckwheat, has seeds with a loose hull and the presence of splits on the sides of the seeds that make dehulling easily. The present study reports on the first attempt of crop improvement in Tartary buckwheat breeding through hybridization. Hybrids were obtained by hybridization of crosses between Tartary buckwheat and Rice-Tartary. Additional crosses were made among selected progenies of these crosses. Based on progeny analysis of the F1, F2, and F3, the character of Rice-Tartary, as exhibited as the presence of splits on the sides of the seeds, is controlled by one gene which is homozygous recessive. A Tartary buckwheat breeding program has been conducted for 6 years based on these crosses. Advanced lines with easy dehull and yield potential are at the stage of ready for yield trials. Production of easy dehulling Tartary buckwheat in the future could boost Canada’s domestic and international markets. [ABSTRACT FROM AUTHOR]

Fagopyrurn homotropium Ohnishi, a wild diploid (2n = 2x = 16) species with self-compatibility expressed by homostylic flowers, has been used for improving cultivated buckwheat, F. esculenturn Moench, a self-incompatible diploid (2n = lx = 16) species with heterostylic pin and thrum flowers. Four crosses were made between F. homotropicum and F. esculentum pin flowers, assisted by ovule rescue in vitro, to study the inheritance and interaction of the two breeding systems in the genus Fagopyrum. The presence of homostylic or pin flowers was used to determine the expression of self-compatibility or self- incompatibility, respectively. The segregation ratios of the F2 progeny derived from F1 single plants, the 8C1F1 generation and the F3 progeny derived from homostylic plants were used to study the inheritance of self-compatibility. Five F2 populations fit a one-gene 3:1 segregation ratio and did not fit a 9:7 ratio, while the other three F2 populations lit a two-gene 9:7 ratio and did not fit a 3:1 ratio. The BC1F1 and F3 progeny segregation confirmed these observations. These results support a two-gene model with three alleles at the first locus S and two alleles at the second locus Sc. The proposed model has S for self- incompatible thrum, S for self-compatible homostyly, and s for self- incompatible pin, with the intrallelic interaction S > Sb > s at the first locus and Sc, for homostyly and s>, for pin (Sc > sj at the second locus. The two complementary dominant genes Sh and Sc control self- compatibility (homostyly) in F. homotropicum. The one gene or two gene segregation patterns are the result of interspecific crosses with different F. esculentum genotypes. [ABSTRACT FROM AUTHOR]

Fagopyrum esculentum Moench, common buckwheat (2n = 2x = 16), is a sporophytic self-incompatible species with dimorphic flowers, which is resistant to seed shattering, a trait often lost in interspecific crosses. The objective of this study was to determine the inheritance of seed shattering in interspecific crosses with the shattering species F. homotropicum Ohnishi [=F. esculentum var. homotropicum (Ohnishi) Q-F. Chen] (2n = 2x = 16) to use this species in buckwheat improvement. Four interspecific crosses between F. homotropicum and F. esculentum were made by means of ovule culture. Eight F2 populations derived from F1 single plants were developed and 28 F3 lines from F2 shattering plants were used for progeny testing. The F1 interspecific hybrids expressed seed shattering, indicating that shattering is dominant to nonshattering. The F2 populations from individual F1 plants segregated in the ratios of 3:1, 9.7, and 27:37, supporting the control of shattering by three complementary dominant genes, the first report of multiple gene control in buckwheat. The F3 progeny testing confirmed the F2 segregation patterns. The different segregation ratios in the F2 populations may have been caused by heterogeneity of F. esculentum because of cross-pollination. The proposed genetic model describes the genotype of F. homotropicum as homozygous dominant to explain the absence of nonshattering genotypes. Fagopyrum esculentum genotypes are homozygous recessive at a minimum of one locus to explain the absence of shattering genotypes. This model provides an explanation for the occurrence of shattering phenotypes from crosses between two nonshattering parents and nonshattering phenotype from crosses between, or selling of, shattering plants. [ABSTRACT FROM AUTHOR]

In 1999, Yang and Shieh proposed a timestamp-based password authentication scheme using smart cards. However, Chan and Fan respectively showed its vulnerability to the forged login attacks proposed by them. Also Fan gave a slight modification of the original scheme, but his modification is not so practical. In this paper a more practical modification of the original scheme will be proposed, which can withstand the forged login attack. [ABSTRACT FROM AUTHOR]

From two aspects; the composition of scientific research management institutions and the tasks undertaken by scientific research management departments, the present situation of scientific and technological management team in agricultural research institutes is expounded. Some problems existed in the scientific and technological management team of provincial agricultural research institutes are analyzed, such as uneven knowledge structure of scientific research management personnel, low degree of specialization, poor stability, lack of professional and systematic job training, etc. Professional development countermeasures are proposed, such as optimizing the structure of scientific research management team, establishing a professional management system with the characteristics of agricultural scientific research institutions, formulating corresponding evaluation mechanism for scientific research management personnel, and strengthening the training of agricultural scientific research management personnel. [ABSTRACT FROM AUTHOR]

In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method can also be applied to the study of pollen xenia effect, pollination tree selection and pure pollen collection in pear tree cultivation. [ABSTRACT FROM AUTHOR]

The actin cytoskeleton is one of the targets of the pH gradient in tip-growing cells, but how cytosolic pH regulates the actin cytoskeleton remains largely unknown. We here demonstrate that Arabidopsis ADF7 and ADF10 function optimally at different pH levels when disassembling actin filaments. This differential pH sensitivity allows ADF7 and ADF10 to respond to the cytosolic pH gradient to regulate actin dynamics in pollen tubes. ADF7 is an unusual actin-depolymerizing factor with a low optimum pH in in vitro actin depolymerization assays. ADF7 plays a dominant role in promoting actin turnover at the pollen tube apex. ADF10 has a typically high optimum pH in in vitro assays and plays a dominant role in regulating the turnover and organization of subapical actin filaments. Thus, functional specification and cooperation of ADF isovariants with different pH sensitivities enable the coordination of the actin cytoskeleton with the cytosolic pH gradient to support pollen tube growth. [ABSTRACT FROM AUTHOR]

This paper analyzes the current situation of training young scientific and technological talents, attracting talents and making good use of talents in Changli Fruit Tree Research Institute of Hebei Academy of Agricultural and Forestry Sciences. There are some problems, such as lack of talent recruitment planning, and lack of follow-up training mechanism. This paper puts forward some measures, such as formulating a scientific recruitment plan, making a follow-up plan for talent training, building an ability-and performance-oriented evaluation mechanism for scientific and technological talents, so as to attach importance to the training of young scientific research talents and promote the echelon construction of the research institute. [ABSTRACT FROM AUTHOR]

The actin-rich cortex plays a fundamental role in many cellular processes. Its architecture and molecular composition vary across cell types and physiological states. The full complement of actin assembly factors driving cortex formation and how their activities are spatiotemporally regulated remain to be fully elucidated. Using Dictyostelium as a model for polarized and rapidly migrating cells, we show that GxcM, a RhoGEF localized specifically in the rear of migrating cells, functions together with F-BAR protein Fbp17, a small GTPase RacC, and the actin nucleation-promoting factor WASP to coordinately promote Arp2/3 complex-mediated cortical actin assembly. Overactivation of this signaling cascade leads to excessive actin polymerization in the rear cortex, whereas its disruption causes defects in cortical integrity and function. Therefore, apart from its well-defined role in the formation of the protrusions at the cell front, the Arp2/3 complex-based actin carries out a previously unappreciated function in building the rear cortical subcompartment in rapidly migrating cells. [ABSTRACT FROM AUTHOR]

The quality of white tea buds is the basis of the quality of finished tea, and sorting white tea buds is a laborious, time-consuming, and key process in the tea-making process. For intelligent detection of white tea buds, this study established the YOLOv5+BiFPN model based on YOLOv5 by adding a Bidirectional Feature Pyramid Network (BiFPN) structure to the neck part. By comparing the YOLOv5 and YOLOv3 through the ablation experiment, it was found that the YOLOv5+BiFPN model could extract the fine features of white tea buds more effectively, and the detection average precision for one bud and one leaf was 98.7% and mAP@0.5 was 96.85%. This study provides a method and means for white tea bud detection based on deep learning image detection, and provides an efficient, accurate, and intelligent bud detection model for high-quality white tea sorting. [ABSTRACT FROM AUTHOR]

Background: Traditional approaches for generating goat pluripotent stem cells (iPSCs) suffer from complexity and low preparation efficiency. Therefore, we tried to derive goat iPSCs with a new method by transfecting exogenous Oct4, Sox2, Klf4 and c-Myc mRNAs into goat embryonic fibroblasts (GEFs), and explore the mechanisms regarding the transcription regulation of the reprogramming factors in goat iPSCs induction. Results: mRNAs of the four reprogramming factors were transfected into GEFs, and were localized in nucleus with approximately 90% transfection efficiency. After five consecutive transfections, GEFs tended to aggregate by day 10. Clones appeared on day 15-18, and typical embryonic stem cell -like clones formed on day 20. One thousand AKP staining positive clones were achieved in 104 GEFs, with approximately 1.0% induction efficiency. Immunofluorescence staining and qRT-PCR detection of the ESCs markers confirmed the properties of the goat iPSCs. The achieved goat iPSCs could be cultured to 22nd passage, which showed normal karyotype. The goat iPSCs were able to differentiate into embryoid bodies with three germ layers. qRT-PCR and western blot showed activated endogenous pluripotent factors expression in the later phase of mRNA-induced goat iPSCs induction. Epigenetic analysis of the endogenous pluripotent gene Nanog revealed its demethylation status in derived goat iPSCs. Core promoter regions of the four reprogramming factors were determined. Transcription factor binding sites, including Elf-1, AP-2, SP1, C/EBP and MZF1, were identified to be functional in the core promoter regions of these reprogramming genes. Demethylation and deacetylation of the promoters enhanced their transcription activities. Conclusions: We successfully generated goat iPSCs by transfection of Oct4, Sox2, Klf4 and c-Myc mRNAs into GEFs, which initiated the endogenous reprogramming network and altered the methylation status of pluripotent genes. Core promoter regions and functional transcription binding sites of the four reprogramming genes were identified. Epigenetic regulation was revealed to participate in mRNA induced iPSCs formation. Our study provides a safe and efficient approach for goat. iPSCs generation. [ABSTRACT FROM AUTHOR]

Water plays a central role in membrane protein folding and function. It not only catalyzes lipid membrane self-assembly but also affects the structural integrity and conformational dynamics of membrane proteins. Magic angle spinning (MAS) solid-state NMR (ssNMR) is the technique of choice for measuring water accessibility of membrane proteins, providing a measure for membrane protein topology and insertion within lipid bilayers. However, the sensitivity and resolution of membrane protein samples for MAS experiments are often dictated by hydration levels, which affect the structural dynamics of membrane proteins. Oriented-sample ssNMR (OS-ssNMR) is a complementary technique to determine both structure and topology of membrane proteins in liquid crystalline bilayers. Recent advancements in OS-ssNMR involve the use of oriented bicellar phases that have improved both sensitivity and resolution. Importantly, for bicelle formation and orientation, lipid bilayers must be well organized and hydrated, resulting in the protein's topology being similar to that found in native membranes. Under these conditions, the NMR resonances become relatively narrow, enabling a better separation of ¹H-15N dipolar couplings and anisotropic 15N chemical shifts with separated local field (SLF) experiments. Here, we report a residue-specific water accessibility experiment for a small membrane protein, sarcolipin (SLN), embedded in oriented lipid bicelles as probed by new water-edited SLF (WE-SLF) experiments. We show that SLN's residues belonging to the juxtamembrane region are more exposed to the water-lipid interface than the corresponding membrane-embedded residues. The information that can be obtained from the WE-SLF experiments can be interpreted using a simple theoretical model based on spin-diffusion theory and offers a complete characterization of membrane proteins in realistic membrane bilayer systems. [ABSTRACT FROM AUTHOR]

Background: The matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a variety of physiological and pathological roles in development, remodeling of tissues and diseases, mainly through degradation of various components of the extracellular matrix (ECM). Particularly, the MMPs have increasingly been found to mediate neuropathology following spinal cord injury (SCI). Proinflammatory mediators are potent activators of the MMPs. However, how the spinal cord regenerative vertebrates circumvent MMPs-mediated neuropathogenesis following SCI remains unclear. Methods: Following the establishment of gecko tail amputation model, the correlation of MMP-1 (gMMP-1) and MMP-3 (gMMP-3) expression with that of macrophage migration inhibitory factor in gecko (gMIF) was assayed by RT-PCR, Western blot and immunohistochemistry. Transcriptome sequencing of primary astrocytes was performed to analyze the intracellular signal transduction of macrophage migration inhibitory factor (MIF). The effects of MMP-1 and MMP-3 induced by MIF on astrocyte migration were assessed by transwell migration assay. Results: The expression of gMIF significantly increased at lesion site of the injured cord, in parallel with those of gMMP-1 and gMMP-3 in the gecko astrocytes (gAS). Transcriptome sequencing and in vitro cell model revealed that gMIF efficiently promoted the expression of gMMP-1 and gMMP-3 in gAS, which in turn contributed to the migration of gAS. Inhibition of gMIF activity following gecko SCI remarkably attenuated astrocytic expression of the two MMPs, and further influenced gecko tail regeneration. Conclusions: Gecko SCI following tail amputation promoted production of gMIF, which induced the expression of gMMP-1 and gMMP-3 in gAS. The gMIF-mediated gMMP-1 and gMMP-3 expression was involved in gAS migration and successful tail regeneration. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lipopolysaccharides (LPS) are the main pathogenic substances in Gram-negative bacteria. The aim of this study was to investigate the preventive effects of dietary curcumin (CUR) on LPS toxicity in the duck ileum. The duck diet was supplemented with CUR (0.5 g kg-1) for 28 days, while the birds were injected with LPS (0.5 mg kg-1 body weight per injection, administered as seven injections in the last week of the experimental period). RESULTS: LPS significantly decreased the ileal villus-to-crypt ratio in the non-supplemented CUR group. Dietary CUR alleviated LPS-induced morphological damage to the ileum. Moreover, dietary CUR alleviated oxidative stress by increasing the levels of total superoxide dismutase (T-SOD) (P < 0.05) and glutathione S-transferase (GST) (P < 0.05) and decreasing the production of malonic dialdehyde (MDA) (P < 0.05) in control ducks and LPS-challenged ducks. Dietary CUR significantly inhibited the LPS-induced massive production of inflammatory factors (IL-1β, IL-6, and TNF-α) (P < 0.05). CUR induced the inhibition of TLR4 and activation of Nrf2 to reduce the expression of inflammation-related genes (TLR4, NF-ΰB, IKK, TXNIP, NLRP3, caspase-1, IL-1β, IL-6, and TNF-α). Moreover, dietary CUR ameliorated the decrease in claudin-1 and occludin expression (P < 0.05) and improved ZO-1 expression in the duck ileum (P < 0.05). CONCLUSION: In conclusion, dietary CUR has beneficial effects on LPS-induced ileal damage, oxidative damage, and inflammatory response by inhibiting the TLR/NF-ΰB and activating the Nrf2 signaling pathways in ducks. This study provides valuable information regarding the therapeutic uses of CUR in duck ileitis. [ABSTRACT FROM AUTHOR]

Protected grape cultivation develops rapidly because of huge economic benefits. However, adverse environmental conditions (insufficient sunlight, high temperature, etc.) in protected cultivation led to low-quality berries. This study aimed to evaluate the effects of berry thinning on the quality attributes of two table grape cultivars (Baoguang and Cuiguang) under linkage greenhouse conditions. Three treatments (L, light berry thinning; M, moderate berry thinning; H, heavy berry thinning) were compared with the control (C, no berry thinning). Berry thinning increased berry weight, total soluble solids (TSS), fructose, glucose, the ratio of TSS to titratable acidity (TA), anthocyanin contents, berry firmness, and mineral contents (Ca, Fe, Na, Mg). Conversely, TA and organic acid profiles were decreased by berry thinning. Cultivars showed significant effects on most of the berry quality parameters. The interaction of cultivars by berry-thinning treatments affected sugar and acid components, anthocyanin contents, and mineral elements. [ABSTRACT FROM AUTHOR]

Amino acids are essential for cell growth and metabolism. Amino acid and growth factor signaling pathways coordinately regulate the mechanistic target of rapamycin complex 1 (mTORC1) kinase in cell growth and organ development. While major components of amino acid signaling mechanisms have been identified, their biological functions in organ development are unclear. We aimed to understand the functions of the critically positioned amino acid signaling complex GAP activity towards Rags 2 (GATOR2) in brain development. GATOR2 mediates amino acid signaling to mTORC1 by directly linking the amino acid sensors for arginine and leucine to downstream signaling complexes. Now, we report a role of GATOR2 in oligodendrocytemyelination in postnatal brain development. We show that the disruption of GATOR2 complex by genetic deletion of meiosis regulator for oocyte development (Mios, encoding a component of GATOR2) selectively impairs the formation of myelinating oligodendrocytes, thus brain myelination, without apparent effects on the formation of neurons and astrocytes. The loss of Mios impairs cell cycle progression of oligodendrocyte precursor cells, leading to their reduced proliferation and differentiation. Mios deletion manifests a cell type-dependent effect on mTORC1 in the brain, with oligodendroglial mTORC1 selectively affected. However, the role of Mios/GATOR2 in oligodendrocyte formation and myelination involves mTORC1-independent function. This study suggests that GATOR2 coordinates amino acid and growth factor signaling to regulate oligodendrocyte myelination. [ABSTRACT FROM AUTHOR]

To further study the fault mechanism and fault features of rolling bearings, a two-DOF rolling bearing fault dynamic model with inner ring local defects considering the bearing radial clearance and time-varying displacement excitation is established based on Hertz contact theory. By comparing the simulated fault signal with bearing fault test data in the time domain and frequency domain, the accuracy of the established fault dynamic model is verified. Finally, the change rules of the characteristic parameters of the bearing inner ring fault signal, including effective value, absolute mean value, square root amplitude, peak value, kurtosis factor, pulse factor, peak factor, and shape factor, are simulated by the fault dynamic model. The results highlight that the proposed fault dynamic model is in good agreement with the experimental results. The model can simulate the fault signal characteristic parameters with the change of defect width, external load, and rotating speed effectively. The study in this paper is of engineering application value for bearing condition monitoring and fault diagnosis. [ABSTRACT FROM AUTHOR]

Current situation of introduction, cultivation and use of high-level talents in agricultural research institutes are analyzed, and the optimized development strategy of further strengthening the construction, introduction, cultivation and use of high-level talent team is thought. It plays a positive role in provincial agricultural research institutes discovering, cultivating and gathering a number of high-quality talents and high-level innovation teams. [ABSTRACT FROM AUTHOR]

Demyelination is one of the pathological outcomes that occur immediately following spinal cord injury. Protection of oligodendrocytes against death/apoptosis proves to be beneficial for the preservation of neurological functions. Suppressors of cytokine signaling 1 protein inhibit the harmful effects of several inflammatory cytokines on oligodendrocytes, but its roles in spinal cord injury (SCI) induced apoptosis of oligodendrocytes remain unclear. We cloned suppressors of cytokine signaling 1 cDNA from Gekko japonicus (Japanese gecko) and analyzed the protein structure revealing the conserved domains contained in other vertebrate suppressors of cytokine signaling 1 proteins. The gecko suppressors of cytokine signaling 1 protein expression were increased in the injured spinal cord following gecko tail amputation and displayed colocalization with oligodendrocytes. The enforced expression of gecko suppressors of cytokine signaling 1 by adenovirus in the Gsn3 gecko oligodendrocyte cell line demonstrated that gecko suppressors of cytokine signaling 1 significantly suppressed cell apoptosis-induced by glucose deprivation. Determination of apoptosis-related proteins revealed that gecko suppressors of cytokine signaling 1 was able to activate extracellular regulated protein kinases (ERK) and serine/threonine protein kinases (Akt). The results presented a distinct protective role of gecko suppressors of cytokine signaling 1 in the regenerative model of the spinal cord, which may provide new cues for central nervous system repair in mammals. [ABSTRACT FROM AUTHOR]

Acute leukemia is a hematological malignant tumor. Long non-coding RNA urothelial cancer-associated 1 (UCA1) is involved in the chemo-resistance of diverse cancers, but it is unclear whether UCA1 is associated with the sensitivity of acute leukemia cells to daunorubicin (DNR). DNR (100 nM) was selected for functional analysis. The viability, cell cycle progression, apoptosis, and invasion of treated acute leukemia cells (HL-60 and U-937) were evaluated by cell counting kit-8 (CCK-8) assay, flow cytometry assay, or transwell assay. Protein levels were detected with Western blot analysis. Expression patterns of UCA1 and miR-613 were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between UCA1 and microRNA-613 (miR-613) was verified by dual-luciferase reporter assay. We observed that UCA1 expression was elevated in HL-60 and U-937cells. DNR constrained viability, cell cycle progression, invasion, and facilitated apoptosis of HL-60 and U-937 cells in a dose-dependent manner, but these impacts mediated by DNR were reverted after UCA1 overexpression. MiR-613 was down-regulated in HL-60 and U-937 cells, and UCA1 was verified as a miR-613 sponge. MiR-613 inhibitor reversed DNR treatment-mediated effects on viability, cell cycle progression, apoptosis, and invasion of HL-60 and U-937 cells, but these impacts mediated by miR-613 inhibitor were counteracted after UCA1 inhibition. Notably, the inactivation of the PI3K/AKT pathway caused by DNR treatment was reversed after miR-613 inhibitor introduction, but this influence mediated by miR-613 inhibitor was offset after UCA1 knockdown. In conclusion, UCA1 up-regulation facilitated the resistance of acute leukemia cells to DNR via the PI3K/AKT pathway by sponging miR-613. [ABSTRACT FROM AUTHOR]

Surface modification has been one of most effective methods to improve the electrochemical performance of lithium rich layered oxides. In this paper, the Li1.2Mn0.56Ni0.16Co0.08O2 microspheres are prepared by urea assisted combustion route, and then coated with proper amount of CaF2. XRD and SEM results show surface modification has not changed the structure of Li1.2Mn0.56Ni0.16Co0.08O2, and a uniform coating layer can be obtained. As lithium ion battery cathode, the optimal CaF2 (i.e, 2 wt.%) coated sample presents a high initial discharge capacity of 223 mAh·g-1 with Coulombic efficiency of 80.5 % at 0.1 C, which is much better than that of pristine sample. Also, a high discharge capacity of 119 mAh·g-1 can be obtained for CaF2 coated sample at 5 C. The improved electrochemical performance may be attributed the formation of fast Li ion conductor on the surface supported by EIS study. [ABSTRACT FROM AUTHOR]

Adult mammalian astrocytes are sensitive to inflammatory stimuli in the context of neuropathology or mechanical injury, thereby affecting functional outcomes of the central nervous system (CNS). In contrast, glial cells residing in the spinal cord of regenerative vertebrates exhibit a weak astroglial reaction similar to those of mammals in embryonic stages. Macrophage migration inhibitory factor (MIF) participates in multiple neurological disorders by activation of glial and immune cells. However, the mechanism of astrocytes from regenerative species, such as gecko astrocytes (gAS), in resistance to MIFmediated inflammation in the severed cords remains unclear. Here, we compared neural stem cell markers among gAS, as well as adult (rAS) and embryonic (eAS) rat astrocytes. We observed that gAS retained an immature phenotype resembling rat eAS. Proinflammatory activation of gAS with gecko (gMIF) or rat (rMIF) recombinant protein was unable to induce the production of inflammatory cytokines, despite its interaction with membrane CD74 receptor. Using cross-species screening of inflammation-related mediators from models of gMIF- and rMIF-induced gAS and rAS, we identified Vav1 as a key regulator in suppressing the inflammatory activation of gAS. The gAS with Vav1 deficiency displayed significantly restored sensitivity to inflammatory stimuli. Meanwhile, gMIF acts to promote the migration of gAS through regulation of CXCL8 following cord lesion. Taken together, our results suggest that Vav1 contributes to the regulation of astrocyte-mediated inflammation, which might be beneficial for the therapeutic development of neurological diseases. [ABSTRACT FROM AUTHOR]

[Objectives] The identification of salt tolerant genetic loci in rice can provide a research basis for the molecular mechanism of salt tolerance and gene resources for improving salt tolerant cultivars. [Methods Recombinant inbred lines (RILs) derived from Zhaxima, an indica landrace variety from Yunnan Province and Nanjing 46, an elite japonica variety with superior grain quality from Jiangsu Province were used. The salt tolerance at seeding stage in the RIL population was investigated as the phenotypic value. [Results] Combined with the linkage map, a total of 4 QTLs were detected: qSST-1 , qSST-3, qSST-5 and qSST-11, located in rice chromosomes 1,3,5 and 11 , respectively. All positive alleles were from the parent Nanjing 46. Three QTLs among them were not included in chromosome intervals the same as cloned rice salt tolerance genes, and thus were described as new candidate gene loci associated with seeding-stage salt tolerance. [Conclusions] This study provides important information for further exploration and utilization of new salt tolerant QTLs in rice. It is of great significance for improving the utilization of saline land in China and ensuring the stable rice production. [ABSTRACT FROM AUTHOR]

In medium-voltage and high-voltage high-power converters, the switching devices need to operate at a low switching frequency to reduce power loss and increase the power capacity. This increases the delay of the signal sampling and PWM. It also makes the cross-couplings of the d-q current components more severe. In addition, the LCL filter has three cross-coupling loops and is prone to resonance. In order to solve these problems, this paper establishes a complex vector model of an LCL type grid-connected converter. Based on this model, two multiple decoupling current control strategies with passive damping / notch damping are proposed for the LCL type grid-connected converter. The proposed strategies can effectively eliminate the cross-couplings of the converter, achieve independent control of the d-q current components, expand the stable region and suppress the resonance of the LCL filter. Simulation and experimental results verify the correctness of the theoretical analysis and the feasibility of the proposed strategies. [ABSTRACT FROM AUTHOR]

Afast neutron detection system based on a scintillating plastic fiber array and multiplexerwas designed to measure the spectrum of fast neutrons ranged 10 MeV-100 MeV. With the method of nuclear recoil, the energy of incident neutron was determined by measuring the recoil proton track and deposited energy in scintillating plastic fibers. The detection system was composed of a scintillating plastic fiber array, 6 position sensitive photomultiplier tubes, and a high-density readout electronics based on the multiplexer. The scintillating plastic fiber array was made as a staggered structure with two kinds of fibers in different sizes (0.5 mm-square fiber and 3 mm-square fiber). The structure provided a wider detection energy range and better detection efficiency than arrays made with uniform plastic fibers. A dedicated digital electronics system was well designed to control the whole readout system to provide 384-channel signal processing. The detector had a 48 mm X 48 mm effective detection area and a mechanical size of 34 cm X 34 cm X 27 cm. In the simulation of the detector model performance, the system gave an energy resolution of 23%-35% for neutrons ranged 10MeV-100MeV. Experimental results showed that the detector had a good energy linearity and energy resolutions were, respectively, 35.82% at 14.817 MeV, 36.84% at 21.264 MeV, 35.90% at 23.069 MeV, and 32.90% at 24.220 MeV. The optimized prototype model had potential in increasing fast neutron detection performance. [ABSTRACT FROM AUTHOR]

K-means plays an important role in different fields of data mining. However, k-means often becomes sensitive due to its random seeds selecting. Motivated by this, this article proposes an optimized k-means clustering method, named k*-means, along with three optimization principles. First, we propose a hierarchical optimization principle initialized by k* seeds (k* > k) to reduce the risk of random seeds selecting, and then use the proposed "top-n nearest clusters merging" to merge the nearest clusters in each round until the number of clusters reaches at k. Second, we propose an "optimized update principle" that leverages moved points updating incrementally instead of recalculating mean and SSE of cluster in k-means iteration to minimize computation cost. Third, we propose a strategy named "cluster pruning strategy" to improve efficiency of k-means. This strategy omits the farther clusters to shrink the adjustable space in each iteration. Experiments performed on real UCI and synthetic datasets verify the efficiency and effectiveness of our proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper presents a coded aperture method to remotely estimate the radioactivity of a source. The activity is estimated from the detected counts and the estimated source location, which is extracted by factoring the effect of aperture magnification. A 6 mm thick tungsten–copper alloy coded aperture mask is used to modulate the incoming gamma-rays. The location of point and line sources in all three dimensions was estimated with an accuracy of less than 10% when the source-camera distance was about 4 m. The estimated activities were 17.6% smaller and 50.4% larger than the actual activities for the point and line sources, respectively. [ABSTRACT FROM AUTHOR]

Background/aim: To repair esophageal defects by hydroxylated and kombucha -synthesized bacterial cellulose (HKBC) patch in a rabbit model. Materials and methods: Semicircular esophageal defects 1 cm in length of the cervical esophagus were initially created in 18 Japanese big-ear rabbits and then repaired with HKBC patch grafts. The clinical outcomes including survival rate, weight change, food intake, and hematological and radiologic evaluation were observed. After X-ray evaluation, the rabbits were sacrificed sequentially at 1, 3, and 6 months for histopathologic analysis with light microscopy and scanning electron microscopy. Results: Survival rate during the first month was 88.9% (n = 16). Two rabbits died from anastomotic leakage during the entire follow-up. Postoperatively, feeding function and body weight were gradually restored in the surviving animals. No hematological abnormalities were found, and no obvious anastomotic leakage, stenosis, or obstruction was observed under X-ray examination. The histopathologic results showed a progressive regeneration of the esophagus in the graft area, where the neo-esophagus tissue had characteristics similar to native esophageal tissue after 3 months of surgery. Conclusion: HKBC is beneficial for esophageal tissue regeneration and may be a promising material for esophageal reconstruction. [ABSTRACT FROM AUTHOR]

Male germ cell differentiation is a subtle and complex regulatory process. Currently, its regulatory mechanism is still not fully understood. In our experiment, we performed the first comprehensive genome and transcriptome-wide analyses of the crucial genes and signaling pathways in three kinds of crucial cells (embryonic stem cells, primordial germ cell, and spermatogonial stem cells) that are associated with the male germ cell differentiation. We identified thousands of differentially expressed genes in this process, and from these we chose 173 candidate genes, of which 98 genes were involved in cell differentiation, 19 were involved in the metabolic process, and 56 were involved in the differentiation and metabolic processes, like GAL9, AMH, PLK1, and PSMD7 and so on. In addition, we found that 18 key signaling pathways were involved mainly in cell proliferation, differentiation, and signal transduction processes like TGF-β, Notch, and Jak-STAT. Further exploration found that the candidate gene expression patterns were the same between in vitro induction experiments and transcriptome results. Our results yield clues to the mechanistic basis of male germ cell differentiation and provide an important reference for further studies. [ABSTRACT FROM AUTHOR]

Abstract: Ultralong Zn3V2O7(OH)2·2H2O nanobelts with widths of 60–80nm, thicknesses of 20–30nm, and lengths up to several tens of micrometers have been successfully prepared on a large scale via a hydrothermal technique without using any surfactants or additives. Electrochemical measurements revealed that the Zn3V2O7(OH)2·2H2O nanobelts displayed high discharge capacity and good cycling stability, indicating that they might find possible applications as promising anode materials in lithium-ion batteries. Significantly, this is the first time that the Zn3V2O7(OH)2·2H2O nanobelt was used as anode materials in lithium-ion batteries. The present work will greatly expand the range of anode choices and could assist long-term endeavors in developing high capacity anode materials for lithium-ion batteries. [Copyright &y& Elsevier]

Rice blast disease is one of the most devastating diseases in rice production, which severely affects the high and stable yield of rice. The formation of appressorium plays a key role in the pathogenesis of Magnaporthe grisea in rice. It has been confirmed that a P-type ATPase(P-ATPase) is involved in the formation of appressorium. A number of small molecular substances are able to enter the pathogen from the host during the interactions between pathogens and hosts, thus resisting the infection of pathogens. In this study, a 232 bp DNA sequence with good specificity from the first exon of P-ATPase gene MgAPT2 was used as an interference fragment and was inserted into interference vector forward and reversely.The interfering vector was then transformed into rice blast-susceptible rice variety Nipponbare via Agrobacterium-mediated transformation. Identification of rice plants inoculated with M. grisea at the seedling stage and detection of the expression level of P-ATPase gene MgAPT2 showed that the expression level of MgAPT2 gene in transgenic plants was reduced and the rice blast resistance was improved. This study provided a new way for the innovation of rice germplasm resources resistant to rice blast disease. [ABSTRACT FROM AUTHOR]