Search

Previous studies have emphasised the positive role of digital technologies in gaining competitive advantage, but the differences between technologies and the role of environmental matching have been overlooked. In this paper, we explore the relative positions and competitive landscape formed by digital technology firms. First, the study uses an NLP approach to measure corporate ecological niche based on digital business, which includes two indicators of width and overlap, and the original corpus comes from the annual reports of 409 listed companies. Then, based on the ecological niche separation theory, we analyse the competitive effects. The results show that the competitive effect formed by the representative digital technology enterprises can be divided into complementary, independent and substitution. Among them, cloud computing and big data enterprises are at the stage of complementary effect, blockchain enterprises form a unique independent competitive pattern, while the substitution effect of artificial intelligence and Internet of Things enterprises is more obvious. This paper implements an ecological niche measure that embodies digital features, which delivers fresh and useful insights into the application of the ecological niche theory in the digital environments and further reveals the unique competitive dynamics in the digital environment. [ABSTRACT FROM AUTHOR]

Understanding gene functions in marine invertebrates has been limited, largely due to the lack of suitable assay systems. Such a system requires investigative methods that are reproducible and can be quantitatively evaluated, such as a cell line, and a strong promoter that can drive high expression of a transgene. In this study, we established primary cell culture from a marine bivalve mollusc, Mizuhopecten yessoensis. Using scallop primary cells, we optimized electroporation conditions for transfection and carried out a luciferase-based promoter activity assay to identify strong promoter sequences that can drive expression of a gene of interest. We evaluated potential promoter sequences from genes of endogenous and exogenous origin and discovered a strong viral promoter derived from a bivalve-infectious virus, ostreid herpesvirus-1 (OsHV-1). This promoter, we termed OsHV-1 promoter, showed 24.7-fold and 16.1-fold higher activity than the cytomegalovirus immediate early (CMV IE) promoter and the endogenous EF1α promoter, the two most commonly used promoters in bivalves so far. Our GFP assays showed that the OsHV-1 promoter is active not only in scallop cells but also in HEK293 cells and zebrafish embryos. The OsHV-1 promoter practically enables functional analysis of marine molluscan genes, which can contribute to unveiling generegulatory networks underlying astonishing regeneration, adaptation, reproduction, and aging in marine invertebrates. [ABSTRACT FROM AUTHOR]

Managing artificial intelligence (AI) marks the dawn of a new age of information technology management. Managing AI involves communicating, leading, coordinating, and controlling an ever-evolving frontier of computational advancements that references human intelligence in addressing ever more complex decisionmaking problems. It means making decisions about three related, interdependent facets of AI--autonomy, learning, and inscrutability--in the ongoing quest to push the frontiers of performance and scope of AI. We demonstrate how the frontiers of AI have shifted with time, and explain how the seven exemplar studies included in this special issue are helping us learn about management at the frontiers of AI. We close by speculating about future frontiers in managing AI and what role information systems scholarship has in exploring and shaping this future. [ABSTRACT FROM AUTHOR]

Zeroth-order (ZO) optimization has been the key technique for various machine learning applications especially for black-box adversarial attack, where models need to be learned in a gradient-free manner. Although many ZO algorithms have been proposed, the high function query complexities hinder their applications seriously. To address this challenging problem, we propose two stagewise black-box reduction frameworks for ZO algorithms under convex and non-convex settings respectively, which lower down the function query complexities of ZO algorithms. Moreover, our frameworks can directly derive the convergence results of ZO algorithms under convex and non-convex settings without extra analyses, as long as convergence results under strongly convex setting are given. To illustrate the advantages, we further study ZO-SVRG, ZO-SAGA and ZO-Varag under strongly-convex setting and use our frameworks to directly derive the convergence results under convex and non-convex settings. The function query complexities of these algorithms derived by our frameworks are lower than that of their vanilla counterparts without frameworks, or even lower than that of state-of-the-art algorithms. Finally we conduct numerical experiments to illustrate the superiority of our frameworks. [ABSTRACT FROM AUTHOR]

Asynchronous stochastic algorithms with various variance reduction techniques (such as SVRG, S2GD, SAGA and q-SAGA) are popular in solving large scale learning problems. Recently, Reddi et al. (2015) proposed an unified variance reduction framework (i.e., HSAG) to analyze the asynchronous stochastic gradient optimization. However, the HSAG framework cannot incorporate the S2GD technique, the analysis of the HSAG framework is limited to the SVRG and SAGA techniques on the smooth convex optimization. They did not analyze other important various variance techniques (e.g., S2GD and q-SAGA) and other important optimization problems (e.g., convex optimization with non-smooth regularization and non-convex optimization with cardinality constraint). In this paper, we bridge this gap by using an unified q-memorization framework for various variance reduction techniques (including SVRG, S2GD, SAGA, q-SAGA) to analyze asynchronous stochastic algorithms for three important optimization problems. Specifically, based on the q-memorization framework, 1) we propose an asynchronous stochastic gradient hard thresholding algorithm with q-memorization (AsySGHT-qM) for the non-convex optimization with cardinality constraint, and prove that the convergence rate of AsySGHT-qM before reaching the inherent error induced by gradient hard thresholding methods is geometric. 2) We propose an asynchronous stochastic proximal gradient algorithm (AsySPG-qM) for the convex optimization with non-smooth regularization, and prove that AsySPG-qM can achieve a linear convergence rate. 3) We propose an asynchronous stochastic gradient descent algorithm (AsySGD-qM) for the general non-convex optimization problem, and prove that AsySGD-qM can achieve a sublinear convergence rate to stationary points. The experimental results on various large-scale datasets confirm the fast convergence of our AsySGHT-qM, AsySPG-qM and AsySGD-qM through concrete realizations of SVRG and SAGA. [ABSTRACT FROM AUTHOR]

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by intellectual disability, lack of speech, ataxia, EEG abnormalities, and epilepsy. Seizures in individuals with AS are common, debilitating, and often drug resistant. Thus, there is an unmet need for better treatment options. Cannabidiol (CBD), a major phytocannabinoid constituent of cannabis, has shown antiseizure activity and behavioral benefits in preclinical and clinical studies for some disorders associated with epilepsy, suggesting that the same could be true for AS. Here, we show that acute CBD (100 mg/kg) treatment attenuated hyperthermia- and acoustically induced seizures in a mouse model of AS. However, neither acute CBD nor a 2-week-long course of CBD administered immediately after a kindling protocol could halt the proepileptogenic plasticity observed in AS model mice. CBD had a dose-dependent sedative effect but did not have an impact on motor performance. CBD abrogated the enhanced intracortical local field potential power, including the delta and theta rhythms observed in AS model mice, indicating that CBD administration could also help normalize the EEG deficits observed in individuals with AS. We believe our results provide critical preclinical evidence supporting CBD treatment of seizures and alleviation of EEG abnormalities in AS and will thus help guide the rational development of CBD as a treatment for AS. [ABSTRACT FROM AUTHOR]

(Mn, Co)-codoped ZnO films have been synthesized on c-sapphire (0001) by a radio-frequency magnetron sputtering system in which two targets were sputtered together. X-ray-diffraction measurements indicate that the films are highly c-axis oriented. X-ray photon spectra show that the doped Mn and Co ions in (Mn, Co) ZnO films are both in the divalent states. The films show ferromagnetic behavior with a coercivity of about 90 Oe and a saturation moment of 0.11μB/(0.3Mn2++0.7Co2+) at 300 K. In the lower temperatures between 5 and 20 K, a relatively large positive magnetoresistance over 10% was observed for (Mn0.03, Co0.07)Zn0.90O film. The number of carrier concentration is experimentally established to be 1.5613×1018 cm-3 and the mobility to be 2.815 cm2 V-1 s-1 for (Mn0.03, Co0.07)Zn0.90O film by Hall measurements at 300 K. The origins of the room-temperature magnetism and the large positive magnetoresistance are also discussed. [ABSTRACT FROM AUTHOR]

Background. The authors of this meta-analysis evaluated whether there is a difference in the levels of serum and gingival crevicular fluid (GCF) matrix metalloproteinase (MfvIP)-9 between patients with periodontitis and periodontally healthy control participants. Types of Studies Reviewed. The authors searched PubMed, Embase, the Cochrane Library, and the China Biology Medicine disk databases for eligible studies in which the investigators reported the relationships between MMP-9 levels in serum and GCF and periodontitis. The authors pooled the standardized mean differences (SMDs) and 95% confidence intervals (CIs) from each study to evaluate the difference in the serum and GCF MMP-9 levels between patients with periodontitis and periodontally healthy control participants. Results. Results of a meta-analysis of 6 case-control studies including a total of 923 healthy control participants and 557 patients with periodontitis indicated that serum MMP-9 levels were significantly higher in patients with periodontitis than in periodontally healthy control participants (SMD, 1.60; 95% CI, 0.17 to 3.03; P < .05). Results of a separate meta-analysis of 6 case-control studies including a total of 153 healthy control participants and 189 patients with periodontitis indicated that GCF MMP-9 levels were significantly higher in patients with periodontitis than in periodontally healthy control participants (SMD, 1.96; 95% CI, 0.76 to 3.16; P < .01). Conclusions and Practical Implications. The results of the meta-analysis revealed statistically significant differences in the MMP-9 levels in serum and GCF between patients with periodontitis and periodontally healthy control participants. These results cannot be used to confirm causality because the included studies were all case-control studies in which the investigators reported associations. Moreover, readers should view the results with caution because of the considerable heterogeneity among the studies included in the meta-analysis. [ABSTRACT FROM AUTHOR]

Angelman syndrome (AS) is a neurodevelopmental disorder in which epilepsy is common (~90%) and often refractory to antiepileptics. AS is caused by mutation of the maternal allele encoding the ubiquitin protein ligase E3A (UBE3A), but it is unclear how this genetic insult confers vulnerability to seizure development and progression (i.e., epileptogenesis). Here, we implemented the flurothyl kindling and retest paradigm in AS model mice to assess epileptogenesis and to gain mechanistic insights owed to loss of maternal Ube3a. AS model mice kindled similarly to wild-type mice, but they displayed a markedly increased sensitivity to flurothyl-, kainic acid-, and hyperthermia-induced seizures measured a month later during retest. Pathological characterization revealed enhanced deposition of perineuronal nets in the dentate gyrus of the hippocampus of AS mice in the absence of overt neuronal loss or mossy fiber sprouting. This pro-epileptogenic phenotype resulted from Ube3a deletion in GABAergic but not glutamatergic neurons, and it was rescued by pancellular reinstatement of Ube3a at postnatal day 21 (P21), but not during adulthood. Our results suggest that epileptogenic susceptibility in AS patients is a consequence of the dysfunctional development of GABAergic circuits, which may be amenable to therapies leveraging juvenile reinstatement of UBE3A. [ABSTRACT FROM AUTHOR]

The necking behavior of sheet metals under stretch-bending process is a challenge for the forming limit prediction. State-of-the-art forming limit curves (FLCs) allow the prediction under the in-plane stretching but fall short in the case under out-of-plane loading condition. To account for the bending and straightening deformation when sheet metal enters a die cavity or slide along a radius, anisotropic hardening model is essential to reflect the nonproportional loading effect on stress evolution. This paper aims to revisit the M-K analysis under the stretch-bending condition and extend it to accommodate both distortionless and distortional anisotropic hardening behavior. Furthermore, hardening models are calibrated based on the same material response. Then the detailed comparison is proposed for providing better insight into the numerical prediction and necking behavior. Finally, the evolution of the yield surface and stress transition states is examined. It is found that the forming limit prediction under stretch-bending condition through the M-K analysis strongly depends on the employed anisotropic hardening model. [ABSTRACT FROM AUTHOR]

The mud crab, Scylla paramamosain Estampador, 1949, is a widely farmed commercial species in the South-East coastal areas of China. The crabs are captured and placed in a water-free container for further transportation. The long-time air exposure makes the crabs suffer from oxidative stress, triggering cell apoptosis and leading to the crab's death. In this study, the homologue of the apoptosis regulator BAX was firstly identified in S. paramamosain and named as SpBAX. The coding region of SpBAX yielded a polypeptide of 278 amino acids, consisting of the defining motif of the BAXs family including Bcl-2 homologous BH1, BH2, BH3 regions and a transmembrane (TM) domain. Subcellular prediction suggested that SpBAX was located in the cytoplasm. The three-dimensional structure showed that SpBAX contained 8 helical regions. Two central α-helices (α5 and α6) flanked on one side by α3 and α4, and on the other side by α1, α2 and α7, which showed the same structure as BAXs in mammals. The highest expression level of SpBAX was detected in hepatopancreas tissue. The expression level of SpBAX was up-regulated in 12 h in hepatopancreas and in 24 h in haemocytes after air exposure. Meanwhile, a flow cytometry assay revealed that the proportion of apoptotic haemocytes exceeded 65% after air exposure for 36 h, showing a significant difference with the control group. These results indicated that the cloned SpBAX might be involved in the response to air exposure stress by causing cell apoptosis. This study may thus be helpful to clarify the mechanisms of the air-exposure stress response in the mud crab. [ABSTRACT FROM AUTHOR]

Springback is an important issue for the application of advanced high-strength steels (AHSS) in the automobile industry. Various studies have shown that it is an effective way to predict springback by using path-dependent material models. The accuracy of these material models greatly depends on the experimental test methods as well as material parameters calibrated from these tests. The present cyclic sheet metal test methods, like uniaxial tension-compression test (TCT) and cyclic shear test (CST), are nonstandard and various. The material parameters calibrated from these tests vary greatly from one to another, which makes the usage of material parameters for the accurate prediction of springback more sophisticated even when the advanced material model is available in commercial software. The focus of this work is to compare the springback prediction accuracy by using the material parameters calibrated from tension-compression test or cyclic shear test, and to further clarify the usage of those material parameters in application. These two types of nonstandard cyclic tests are successfully carried out on a same test platform with different specimen geometries. One-element models with corresponding tension-compression or cyclic shear boundary conditions are built, respectively, to calibrate the parameters of the modified Yoshida-Uemori (YU) model for these two different tests. U-bending process is performed for springback prediction comparison. The results show, for dual phase steel (DP780), the work hardening stagnation is not evident by tension-compression tests at all the prestrain levels or by cyclic shear test at small prestrain γ= 0.20 but is significantly apparent by cyclic shear tests at large prestrain γ= 0.38, 0.52, 0.68, which seems to be a prestrain-dependent phenomenon. The material parameters calibrated from different types of cyclic sheet metal tests can vary greatly, but it gives slight differences of springback prediction for U-bending by utilizing either tension-compression test or cyclic shear test. [ABSTRACT FROM AUTHOR]

In this paper, a method is proposed to secure an autonomous underwater blasting vibration test (UBVT) system with plugs to deep-water rock, and its specific configuration concept and plugging principle are illustrated. Using the principle of statics, a mathematical model is established for the squeezing force in the process of pressing the hole-plug device (HPD) into holes in rocks. The tension-compression test is conducted on the plugs in round granite holes to obtain the axial pressure-displacement curves of the pressing process with the HPD spring parameter k, friction coefficient μ between the HPD and the rock-wall, and the dynamic contact friction attributes between the metallic HPD and the rock-wall of hole in granite. The axial pressure with such parameters as k, μ, and the squeezing velocity v, among others, and the four steps of the pressing process are numerically simulated. The relations of the characteristic squeezing force with k, μ, and k, as well as the mechanisms of these parameters that influence HPD usage and the sensitivity coefficient, are revealed. The findings of the present study provide references for setting the HPD configuration parameters and for formulating plug-specific construction methods. [ABSTRACT FROM AUTHOR]

Equipment for breaking and blasting large barriers (EBBLB) is new break-blast equipment, which inevitably induces ground vibration and may cause substantial damage to rock mass and nearby structures as well as human beings. The ground vibration induced by break-blast is one of the inevitable outcomes. By monitoring vibration at measuring points at different distances from blasting center, time history curve of vibrating velocity can be obtained; it can be drawn that blasting seismic waves are generated mainly from the explosion of the precharge. Furthermore, different approaches have been adopted to fit relationship between particle peak velocity (PPV) and distance from blasting center, comparative analysis of which provides the most appropriate relation expression to predict attenuation of PPV of vibration with distance from blasting center. The relation between vibration frequency and distance from blasting center is obtained by Fourier transform. And the research decomposes vibrating signals in vertical direction of different distances from blasting center with Hilbert-Huang Transform (HHT), extracting information of empirical mode components of blasting vibration signals; thus vibrating signals are contracted by spectrum information and energy information, three-dimensional energy, and energy attenuation of vibration with different distances from blasting center. The study can predict ground vibration generated by EBBLB and assess its damaging effects of blasting vibration for security and protection. [ABSTRACT FROM AUTHOR]

State-of-the-art low-power-level metal-oxide-semiconductor field-effect transistor (MOSFET)-based transformerless photovoltaic (PV) inverters can achieve high efficiency by using latest super junction MOSFETs. However, these MOSFET-based inverter topologies suffer from one or more of these drawbacks: MOSFET failure risk from body diode reverse recovery, increased conduction losses due to more devices, or low magnetics utilization. By splitting the conventional MOSFET-based phase leg with an optimized inductor, this paper proposes a novel MOSFET-based phase leg configuration to minimize these drawbacks. Based on the proposed phase leg configuration, a high efficiency single-phase MOSFET transformerless inverter is presented for the PV microinverter applications. The pulsewidth modulation (PWM) modulation and circuit operation principle are then described. The common-mode and differential-mode voltage model is then presented and analyzed for circuit design. Experimental results of a 250 W hardware prototype are shown to demonstrate the merits of the proposed transformerless inverter on nonisolated two-stage PV microinverter application. [ABSTRACT FROM AUTHOR]

Hysteresis current control is an attractive nonlinear current-control method for voltage source inverters when a fast system response is required. A well-known disadvantage of hysteresis current control is that the system has to operate over a wide switching frequency range. This causes an increase in the switching losses of the system and increases the difficulty in designing the output filter. The recently proposed parabolic current control solves this problem by employing a pair of parabolic carriers as the control band. Through the use of parabolic current control, constant switching frequency can be achieved. In the implementation of parabolic current control, dead time is employed to prevent shoot through of the inverter leg. The employment of dead time impacts the current-tracking precision and the stability range of the parabolic current-control method. Another side effect of using dead time is that the switching frequency deviates from the desired value. In this paper, the effects of dead time on parabolic current control are analyzed, and a compensation method is proposed for voltage source inverters that use parabolic current control. Using the output current direction of the voltage source inverter, a new pair of improved parabolic carriers is derived. As a result, the current error can be well controlled and the effects of dead time can be eliminated. The improvement in the current tracking of the system comes with an added benefit where the duty cycle range is extended. The effectiveness of the proposed dead-time compensation method is experimentally verified by the use of a full-bridge voltage source inverter. [ABSTRACT FROM AUTHOR]

This paper presents a nonisolated, high boost ratio dc-dc converter with the application for photovoltaic (PV) modules. The proposed converter utilizes a hybrid transformer to incorporate the resonant operation mode into a traditional high boost ratio active-clamp coupled-inductor pulse-width-modulation dc-dc converter, achieving zero-voltage-switching (ZVS) turn-on of active switches and zero-current-switching turn-off of diodes. As a result of the inductive and capacitive energy being transferred simultaneously within the whole switching period, power device utilization (PDU) is improved and magnetic utilization (MU) is optimized. The improved PDU allows reduction of the silicon area required to realize the power devices of the converter. The optimized MU reduces the dc-bias of magnetizing current in the magnetic core, leading to smaller sized magnetics. Since the magnetizing current has low dc-bias, the ripple magnetizing current can be utilized to assist ZVS of main switch, while maintaining low root-mean-square (RMS) conduction loss. The voltage stresses on the active switches and diodes are maintained at a low level and are independent of the wide changing PV voltages as a result of the resonant capacitor in series in the energy transfer loop. The experimental results based on 250 W prototype circuit show 97.7% peak efficiency and system CEC efficiencies greater than 96.7% over 20 to 45 V input voltages. Due to the high efficiency over wide power range, the ability to operate with a wide variable input voltage and compact size, the proposed converter is an attractive design for PV module applications. [ABSTRACT FROM AUTHOR]

Background: Limited available sequence information has greatly impeded population genetics, phylogenetics and systematics studies in the subclass Acari (mites and ticks). Mitochondrial (mt) DNA is well known to provide genetic markers for investigations in these areas, but complete mt genomic data have been lacking for many Acari species. Herein, we present the complete mt genome of the scab mite Psoroptes cuniculi. Methods: P. cuniculi was collected from a naturally infected New Zealand white rabbit from China and identified by morphological criteria. The complete mt genome of P. cuniculi was amplified by PCR and then sequenced. The relationships of this scab mite with selected members of the Acari were assessed by phylogenetic analysis of concatenated amino acid sequence datasets by Bayesian inference (BI), maximum likelihood (ML) and maximum parsimony (MP). Results: This mt genome (14,247 bp) is circular and consists of 37 genes, including 13 genes for proteins, 22 genes for tRNA, 2 genes for rRNA. The gene arrangement in mt genome of P. cuniculi is the same as those of Dermatophagoides farinae (Pyroglyphidae) and Aleuroglyphus ovatus (Acaridae), but distinct from those of Steganacarus magnus (Steganacaridae) and Panonychus citri (Tetranychidae). Phylogenetic analyses using concatenated amino acid sequences of 12 protein-coding genes, with three different computational algorithms (BI, ML and MP), showed the division of subclass Acari into two superorders, supported the monophylies of the both superorders Parasitiformes and Acariformes; and the three orders Ixodida and Mesostigmata and Astigmata, but rejected the monophyly of the order Prostigmata. Conclusions: The mt genome of P. cuniculi represents the first mt genome of any member of the family Psoroptidae. Analysis of mt genome sequences in the present study has provided new insights into the phylogenetic relationships among several major lineages of Acari species. [ABSTRACT FROM AUTHOR]

Three newlanthanide complexes [Ln(hfac)3(pz)2] (Ln=Dy (1), Tb (2), Ho (3); hfac = hexafluoroacetylacetonate; pz = pyrazole) based on pyrazole have been prepared and characterized structurally. X-ray crystallographic analysis reveals that all three complexes are isomorphous. The crystal structures of these complexes consist of a mononuclear molecule unit in which the center LnIII ion is surrounded with a slightly distorted D2d-dodecahedron LnO6N2 coordination sphere from three hfac anions and two pyrazole ligands. Both static and dynamic magnetic properties were studied for complex 1, which is proved to be a rarely reported D2d-symmetry DyIII mononuclear single-molecule magnet containing a monodentate N-heterocyclic donor ligand, and the luminescence characterization of complexes 1-3 in both visible and NIR regions is also studied. [ABSTRACT FROM AUTHOR]

This paper presents a high-reliability single-phase transformerless grid-connected inverter that utilizes superjunction MOSFETs to achieve high efficiency for photovoltaic applications. The proposed converter utilizes two split ac-coupled inductors that operate separately for positive and negative half grid cycles. This eliminates the shoot-through issue that is encountered by traditional voltage source inverters, leading to enhanced system reliability. Dead time is not required at both the high-frequency pulsewidth modulation switching commutation and the grid zero-crossing instants, improving the quality of the output ac-current and increasing the converter efficiency. The split structure of the proposed inverter does not lead itself to the reverse-recovery issues for the main power switches and as such superjunction MOSFETs can be utilized without any reliability or efficiency penalties. Since MOSFETs are utilized in the proposed converter high efficiency can be achieved even at light load operations achieving a high California energy commission (CEC) or European union efficiency of the converter system. It also has the ability to operate at higher switching frequencies while maintaining high efficiency. The higher operating frequencies with high efficiency enables reduced cooling requirements and results in system cost savings by shrinking passive components. With two additional ac-side switches conducting the currents during the freewheeling phases, the photovoltaic array is decoupled from the grid. This reduces the high-frequency common-mode voltage leading to minimized ground loop leakage current. The operation principle, common-mode characteristic and design considerations of the proposed transformerless inverter are illustrated. The total losses of the power semiconductor devices of several existing transformerless inverters which utilize MOSFETs as main switches are evaluated and compared. The experimental results with a 5 kW prototype circuit show 99.0% CEC efficiency and 99.3% peak efficiency with a 20 kHz switching frequency. The high reliability and efficiency of the proposed converter makes it very attractive for single-phase transformerless photovoltaic inverter applications. [ABSTRACT FROM AUTHOR]

Background: It has long been proposed that early embryos and reproductive organs exhibit similar gene expression profiles. However, whether this similarity is propagated to the protein level remains largely unknown. We have previously characterised the promiscuous expression pattern of cell surface proteins on mouse embryonic stem (mES) cells. As cell surface proteins also play critical functions in human embryonic stem (hES) cells and germ cells, it is important to reveal whether a promiscuous pattern of cell surface proteins also exists for these cells. Methods and Principal Findings: Surface proteins of hES cells and human mature sperms (hSperms) were purified by biotin labelling and subjected to proteomic analyses. More than 1000 transmembrane or secreted cell surface proteins were identified on the two cell types, respectively. Proteins from both cell types covered a large variety of functional categories including signal transduction, adhesion and transporting. Moreover, both cell types promiscuously expressed a wide variety of tissue specific surface proteins, and some surface proteins were heterogeneously expressed. Conclusions/Significance: Our findings indicate that the promiscuous expression of functional and tissue specific cell surface proteins may be a common pattern in embryonic stem cells and germ cells. The conservation of gene expression patterns between early embryonic cells and reproductive cells is propagated to the protein level. These results have deep implications for the cell surface signature characterisation of pluripotent stem cells and germ cells and may lead the way to a new area of study, i.e., the functional significance of promiscuous gene expression in pluripotent and germ cells. [ABSTRACT FROM AUTHOR]

Background: Germline mutations in a tumor suppressor gene FLCN lead to development of fibrofolliculomas, lung cysts and renal cell carcinoma (RCC) in Birt-Hogg-Dubé syndrome. TFE3 is a member of the MiTF/TFE transcription factor family and Xp11.2 translocations found in sporadic RCC involving TFE3 result in gene fusions and overexpression of chimeric fusion proteins that retain the C-terminal DNA binding domain of TFE3. We found that GPNMB expression, which is regulated by MiTF, was greatly elevated in renal cancer cells harboring either TFE3 translocations or FLCN inactivation. Since TFE3 is implicated in RCC, we hypothesized that elevated GPNMB expression was due to increased TFE3 activity resulting from the inactivation of FLCN. Methodology/Principal Findings: TFE3 knockdown reduced GPNMB expression in renal cancer cells harboring either TFE3 translocations or FLCN inactivation. Moreover, FLCN knockdown induced GPNMB expression in FLCN-restored renal cancer cells. Conversely, wildtype FLCN suppressed GPNMB expression in FLCN-null cells. FLCN inactivation was correlated with increased TFE3 transcriptional activity accompanied by its nuclear localization as revealed by elevated GPNMB mRNA and protein expression, and predominantly nuclear immunostaining of TFE3 in renal cancer cells, mouse embryo fibroblast cells, mouse kidneys and mouse and human renal tumors. Nuclear localization of TFE3 was associated with TFE3 posttranslational modifications including decreased phosphorylation. Conclusions/Significance: Increased TFE3 activity is a downstream event induced by FLCN inactivation and is likely to be important for renal tumor development. This study provides an important novel mechanism for induction of TFE3 activity in addition to TFE3 overexpression resulting from Xp11.2 translocations, suggesting that TFE3 may be more broadly involved in tumorigenesis. [ABSTRACT FROM AUTHOR]

The interest in the effects of shock on HDDs has come into currency due to the reduction of the flying height of the head/disk interface and the increasingly hostile environments encountered in the usage of many consumer electronics and portable devices. This paper discusses the shock pulse amplitude and width effects on the shock response of an operational disk drive. The drive is subjected to half sine acceleration shock pulse with varying amplitude and width. A finite element model of the hard disk drive is developed in the commercially available finite element package, ANSYS/LSDYNA. The air bearing between the disk and the slider is modeled by nonlinear springs. The contact between the disk and the slider is also considered. It is found that the shock response of the drive is sensitive to both the shock pulse amplitude and width. [ABSTRACT FROM AUTHOR]

In this paper, dynamic forces of a head arm assembly (HAA) of a hard disk drive (HDD) against an impact load and in free oscillation after an impact load are obtained by means of finite element analysis (FEA) and by carrying out experiments using a modified levitation mass method (LMM). A good correlation between the experimental and numerical results is achieved. The effectiveness of both FE simulation and LMM method in measuring the minute dynamic forces involved in HDDs is evaluated. [ABSTRACT FROM AUTHOR]

We present an efficient protocol for polarization entanglement generation from spatially correlated photons in spontaneous parametric down-conversion. Compare with the protocol proposed by Shimuzu et al. (Phys. Rev. A77 032338), only one polarizing beam splitter is used in this protocol, which makes it simpler and more convenient in a practical application. By increasing the number of the slits, we provide a way for generation of a hyperentangled state in both the spatial and polarization degrees of freedom. [ABSTRACT FROM AUTHOR]

We present a scheme for multiparty quantum remote secret conference (MQRSC) with pure entangled states, not maximally entangled multipartite quantum systems. The conferees first share a private quantum key, a sequence of pure entangled states and then use them to encode and decode the secret messages. The conferees exploit the decoy-photon technique to ensure the security of the transmission of qubits. This MQRSC scheme is more feasible and efficient than others. [ABSTRACT FROM AUTHOR]

As small form factor (one-inch and smaller) hard disk drives are widely used in portable consumer appliances and gadgets, their mechanical robustness is of greater concern. In the previous work, it is found that when the disk is more tightly clamped, it helps to decrease the shock response of the disk and then avoid the head slap. In this paper, the real boundary condition of the disk for a small form factor hard disk drive from Seagate is investigated numerically. The disk is clamped between the clamp and the hub. The shock response of the disk under a half-sine acceleration pulse is simulated by using the finite element method. In the finite element model, both contact between disk and clamp and contact between disk and hub are considered. According to the simulation results, how to decrease the shock response of the disk is suggested. [ABSTRACT FROM AUTHOR]

Low-energy ions exist widely in the natural world. People had neglected the interaction between low-energy ions and material; it was even more out of the question to study the relation of low-energy ions and the complicated organism until the biological effects of low-energy ion implantation were discovered in 1989. Nowadays, the value of low-energy ion beam implantation, as a new breeding way, has drawn extensive attention of biologists and breeding experts. In this review, the understanding and utilization of microbial breeding by low-energy ion beam irradiation is summarized, including the characteristics of an ion beam bioengineering facility, present status of the technology of low-energy ions for microbial breeding, and new insights into microbial biotechnology. [ABSTRACT FROM AUTHOR]

We report here the development of a group of rabbit monoclonal antibodies against Smad1, Smad2, Smad3, and Smad5, and the immunocytochemistry (ICC) staining of human embryonic stem cells (hESC) and mouse embryonic stem cells (mESC). Eight New Zealand rabbits were immunized with synthesized peptides linked to KLH, and splenocytes from these rabbits were fused with rabbit immortal B cell 240E-W2. Resulting hybridomas producing anti-Smad monoclonal antibodies were screened by enzyme-linked immunosorbent assay (ELISA) with BSA-linked peptides. Clones were chosen for antibody production based on their activities in Western blotting and on paraffin-embedded human tissues, and the capacity of the antibodies in immunocytochemistry was demonstrated. Using these antibodies, we performed ICC staining on routinely cultured human and mouse embryonic stem cells, and showed that both cell types strongly express these genes. We propose that both hESCs and mESCs have the ability to transduce signals from both BMPs and TGFb/ Activin. [ABSTRACT FROM AUTHOR]

Agrobacterium tumefaciens ATCC4452 cells were irradiated by nitrogen ion beam, a new mutagen, with energy of 10 keV and fluence ranging from 2.6×1014 ions/cm2 to 6.5×1015 ions/cm2. A similar “saddle shape” survival curve due to ion beam irradiation appeared again in this study. Some mutants with high yield of ubiquinone-10 were induced by ion implantation. High mutation rate and wide mutation spectrum were also observed in the experiment. These results suggested that the mutagenic effect of such low-energy ion influx into bacterium cells could result from multiple processes involving direct collision of particles with cytoplasm, nucleolus, and cascade atomic and molecular reactions due to plentiful primary and secondary particles. [ABSTRACT FROM AUTHOR]

A highly stable convection-cooled, cluster-based voltage divider chain for photomultiplier tubes has been designed and tested in single ion counting detection systems. Contrasting currently existing voltage divider chains, our unit does not require a cooling liquid to transfer the heat from the resistors and provides safer operation conditions inside ultrahigh vacuum systems utilized in the reaction dynamics community. The unit is enclosed in an air pocket inside an ultrahigh vacuum system so that outgassing of the photomultiplier tubes, resistors, and capacitors can be eliminated completely. The measured resistor chain currents of ±2% lie well within the tolerances of the resistors (±5%) and power supply (±1%) demonstrating that the convective cooling is actually efficient to sustain a stable signal. The monitored total ion current also depicts extremely low fluctuation of only 1.5%. The day-to-day reproducibility has been tested, too. We also demonstrate that a magnetic shielding of the photomultiplier tube and the resistor chain enhances the signal by about 15%. [ABSTRACT FROM AUTHOR]

Presents a study that examined the growth and senescence of cultured soybean cells after the ethylene induction of ascobate peroxidase (AsPOX). Changes in ethylene production and AsPOX activity in cultured soybean cells; Effect of sulfur thiosulfate and 2-chloroethylphosphonic acid on AsPOX activity; Impact of exogenous hydrogen peroxide and 1,3-dimethyl-2-thiourea on AsPox activity; Differences in the level of AsPOX transcript.

In this work, multifunctional cellulose membranes (Ag-NWs/CMs@Ag) with antibacterial activities, high air permeability, and infrared preservation properties were successfully prepared for personal thermal management application. Infrared radiation preservation was observed by modifying surface's physical and chemical properties. Additionally, Ag-NWs/CMs@Ag exhibits high air permeability of 3.00 mg/cm2·hour, the excellent antibacterial activity against E. coli and S. aureus and hydrophobic properties with a stable water contact angle of 129.35°. Overall, the results of this study demonstrate Ag-NWs/CMs@Ag offers great potential in personal thermal management application and provide an effective strategy for the development of wearable textiles. [ABSTRACT FROM AUTHOR]

To realize the hole-mediated ferromagnetism, manganese and nitrogen-codoped ZnO (Zn1-xMnxO:N) films were prepared on sapphire (0001) by reactive radio-frequency (rf) magnetron sputtering from Zn0.97Mn0.03O ceramic targets using N2 gas. X-ray photon spectra reveal that the doped Mn ions are mainly in divalent states and the coexistence of O–Zn and N–Zn bonds in the films. According to the absorption spectra, the band gap of Zn0.97Mn0.03O:N films is about 3.15 eV, which is slightly lower than that of ZnO films (3.20 eV). Compared with Zn0.97Mn0.03O films, ferromagnetic behavior of Zn0.97Mn0.03O:N films were significantly changed with a coercivity of about 70 Oe, a saturation magnetization of 0.92 μB/Mn2+ and a remanance over 0.15 μB/Mn2+ at 300 K, while at 10 K, they increased to be about 110 Oe, 1.05 μB/Mn2+ and 0.23 μB/Mn2+, respectively. However, rapid thermal annealing treatment in pure oxygen results in a significant decrease on the magnetic properties of the films. [ABSTRACT FROM AUTHOR]

The circuit diagram and design principles of a high-stability chopper wheel motor driver are presented. Experimental results show that this unit can be interfaced to molecular-beam machines to generate supersonic beams with extremely stable root-mean-square and peak velocities fluctuating on a day-to-day basis by less than 0.2%. [ABSTRACT FROM AUTHOR]

Fluorescent proteins and epitope tags can reveal protein localization in cells and animals, yet the large size of many tags hinders efficient genome targeting. Accordingly, many studies have relied on characterizing overexpressed proteins, which might not recapitulate endogenous protein activities. Here, we present two strategies for higher throughput production of endogenous protein reporters in mice, focusing on the blastocyst model of development. Our first strategy makes use of a split fluorescent protein, mNeonGreen2 (mNG2). Knock-in of a small portion of the mNG2 gene, in frame with gene coding regions of interest, was highly efficient in embryos, potentially obviating the need to establish mouse lines. When complemented by the larger portion of the mNG2 gene, fluorescence was reconstituted and endogenous protein localization faithfully reported in living embryos. Our second strategy achieves in-frame knock-in of a relatively small protein tag, which provides high efficiency and higher sensitivity protein reporting. Together, these two approaches provide complementary advantages and enable broad downstream applications. [ABSTRACT FROM AUTHOR]

In recent years, various early warning signals of critical transition have been presented, such as autocorrelation at lag 1 [AR(1)], variance, the propagator based on detrended fluctuation analysis (DFA-propagator), and so on. Many studies have shown that the climate system has the characteristics of long-term memory (LTM). Will the LTM characteristics of the climate system change as it approaches possible critical transition points? In view of this, the present paper first studies whether the LTM of several folding (folded bifurcation) models changes consistently as they approach their critical points slowly by the rescaled range (R/S) analysis. The results of numerical experiments show that when the control parameters of the folding model are close to its critical threshold, the Hurst exponent H exhibits an almost monotonic increase (significance level α = 0.05). We compare the performance of R/S with the existing indicators, including AR(1), variance, and DFA-propagator, and find that R/S is a perfectly valid alternative. When there is no extra false noise, AR(1) and variance have good early warning effects. After the addition of extra Gaussian white noise of different intensities, the values of AR(1) and variance change significantly. As a result, the DFA-propagator based on AR(1) calibration also changed significantly. Compared with the other three indicators, the early warning effect of H has stronger ability to resist the interference of external false signals. To further verify the validity of increasing H, paleoclimate reconstruction of Cariaco Basin sediment core grayscale record with long trends filtered out is studied by R/S analysis. The other three early warning signals are calculated in the same way. The data contain a well-known abrupt climate change: the transition between the Younger Dryas (YD) and the Holocene. We find that approximately 300 years before this abrupt climate change occurred, before 11.7 kyr BP, the LTM exponents for Cariaco Basin deglacial grayscale data present an obvious increasing trend at a significant level of α = 0.05. Meanwhile, the variation trend of H and DFA-propagator is basically similar. This shows that increasing H by R/S analysis is an effective early warning signal, which indicates that a dynamic system is approaching its possible critical transition points; H is a completely valid alternative signal for AR(1) and DFA-propagator. The main conclusion of this paper is based on numerical experiments. The precise relationship between H and the stability of the underlying state approaching the transition needs to be further studied. [ABSTRACT FROM AUTHOR]

Background: Melanocytic nevus is mainly treated by complete or partial removal. However, predicting the risk of malignant transformation of melanocytic nevi and which treatment patients should receive, surgical or nonsurgical management, to gain the best results and aesthetic outcomes is controversial. Methods: Global literature on melanocytic nevus treatment, published between 1997 and 2022, was scanned using the Web of Science Core Collection database. Microsoft Office Excel, CiteSpace V, VOSviewer, Scimago Graphica, Bibliometrix, and Biblioshiny packages in R were used for the bibliometric analysis to summarize the leading countries, institutions, professors, and research trends in this field. Results: This study included 1 723 articles. Publications and citations exhibited positive trends over the past 20 years. The United States had the most productive organizations and publications in the comprehensive worldwide cooperation network, and China was recently one of the most active major participants. Professor Giovanni Pellacani, whose H-index, G-index, and M-index ranked first in this field, founded a virtual biopsy using reflectance confocal microscopy. In addition, Krengel and Kinsler contributed significantly to diagnosing and treating melanocytic nevi. The top 25 keywords in recent years were mostly about the mechanisms and risk factors for the malignant transformation of nevi. Conclusion: The future trend for melanocytic nevi treatment is to specify genotype-phenotype and genotypeoutcome correlations, choose proper therapy to reduce the risk of malignant transformation, and simultaneously achieve the best aesthetic outcomes. [ABSTRACT FROM AUTHOR]

Depression is a common and debilitating condition for which effective treatments are needed. Lepidium meyenii Walp (Maca) is a plant with potential medicinal effects in treating depression. Recently, there has been growing interest in plant-derived extracellular vesicles (EVs) due to their low toxicity and ability to transport to human cells. Targeting the gut-brain axis, a novel strategy for depression management, may be achieved through the use of Maca-derived EVs (Maca-EVs). In this study, we successfully isolated Maca-EVs using gradient ultracentrifugation and characterized their shape, size, and markers (CD63 and TSG101). The in vivo imaging showed that the Dil-labeled Maca-EVs crossed the brain-blood barrier and accumulated in the brain. The behavioral tests revealed that Maca-EVs dramatically recovered the depression-like behaviors of unpredictable chronic mild stress (UCMS) mice. UCMS mice fecal were characterized by an elevated abundance of g_Enterococcus, g_Lactobacillus, and g_Escherichia_Shigella, which were significantly restored by administration of Maca-EVs. The effects of Maca-EVs on the altered microbial and fecal metabolites in UCMS mice were mapped to biotin, pyrimidine, and amino acid (tyrosine, alanine, aspartate, and glutamate) metabolisms, which were closely associated with the serotonin (5-HT) production. Maca-EVs were able to increase serum monoamine neurotransmitter levels in UCMS mice, with 5-HT showing the most significant changes. We further demonstrated that 5-HT improved the expression of brain-derived neurotrophic factor, a key regulator of neuronal plasticity, and its subsequent activation of TrkB/p-AKT signaling by regulating the GTP-Cdc42/ERK pathway. These findings suggest that Maca-EVs enhance 5-HT release, possibly by modulating the gut-brain axis, to improve depression behavior. Our study sheds light on a novel approach to depression treatment using plant-derived EVs. [ABSTRACT FROM AUTHOR]

Experiments were conducted to study the mechanical characteristics of arkosic sandstones sampled from Pingyi, China. Rock samples were all thermally treated under the temperature ranging from room temperature to 800 °C. Results show that as the treatment temperature rises, the arkosic mineral composition does not change obviously, but the mechanical behaviors change regularly. Variation trend changes dramatically at 200 °C, 400 °C, and 500 °C. With thermal expansion of mineral particles being the dominant factor, mechanical behaviors barely change below 200 °C. When temperature ranges from 200-400 °C, it has an important effect on the mechanical properties because of the thermal fracture. From 400-500 °C, mechanical properties change dramatically as a result of the mutual influence of thermal fracture, fusion and re-crystallization, but the thermal fracture is the leading factor. Because of the fusion and re-crystallization, fractures are partly filled, which results in partial recovering of the mechanical strength. With the combined action of thermal fracture, fusion and re-crystallization after 600 °C, mechanical performance of arkosic sandstones degrades rapidly. Generally, the porosity and peak strain of arkosic sandstones increase with the temperature rising. However, the peak stress, elastic modulus and deformation modulus decrease simultaneously. Influenced by mineral particles' thermal expansion, thermal fracture, fusion, and re-crystallization and so on, the variation trend and amplitude are not the same at different temperature ranges, and the damage mechanism of sandstones also makes a difference. [ABSTRACT FROM AUTHOR]

Background: Various techniques have been developed for postburn neck reconstruction, but a treatment algorithm is needed. Methods: We retrospectively reviewed all patients treated for postburn neck contracture at our institution between February 2008 and December 2015. Necks were divided into one anterior subunit and two lateral subunits marked by the sternocleidomastoid muscle. Deformities were categorized into three types according to their size and location. Type I deformities involve less than one subunit, type II deformities involve at least one subunit but less than two subunits, and type III deformities affect two ormore subunits. Type II deformities were further divided into type IIa deformities, whichmainly involve the anterior region, and type IIb deformities, whichmainly involve the lateral region. Results: Local random pattern flaps were constructed for type I deformities. Pedicled flaps from the anterior chest and supraclavicular areas were preferred for type IIa deformities, and pedicled flaps from the back were preferred for type IIb deformities. Pedicled flaps fromother areas were the second choice for type II deformities, followed by free and prefabricated flaps. For type III deformities, bipedicled flaps were usually required. At a follow-up of at least 12 months, all patients showed near-normal neck function, and aesthetic features were significantly improved. Conclusion: The proposed classification and treatment algorithm for postburn neck reconstruction may help achieve satisfactory outcomes. [ABSTRACT FROM AUTHOR]

Human herpesvirus 6 (HHV-6) is an important immunosuppressive and immunomodulatory virus that primarily infects immune cells and strongly suppresses the proliferation of infected cells. However, the mechanisms responsible for the regulation and suppression mediated by HHV-6 are still unknown. In this study, we examined the ability of HHV-6A to manipulate cell cycle progression in infected cells and explored the potential molecular mechanisms. We demonstrated that infection with HHV-6A imposed a growth-inhibitory effect on HSB-2 cells by inducing cell cycle arrest at the G2/M phase. We then showed that the activity of the Cdc2-cyclin B1 complex was significantly decreased in HHV-6A-infected HSB-2 cells. Furthermore, we found that inactivation of Cdc2-cyclin B1 in HHV-6A-infected cells occurred through the inhibitory Tyr15 phosphorylation resulting from elevated Wee1 expression and inactivated Cdc25C. The reduction of Cdc2-cyclin B1 activity in HHV-6-infected cells was also partly due to the increased expression of the cell cycle-regulatory molecule p21 in a p53-dependent manner. In addition, HHV-6A infection activated the DNA damage checkpoint kinases Chk2 and Chk1. Our data suggest that HHV-6A infection induces G2/M arrest in infected T cells via various molecular regulatory mechanisms. These results further demonstrate the potential mechanisms involved in immune suppression and modulation mediated by HHV-6 infection, and they provide new insights relevant to the development of novel vaccines and immunotherapeutic approaches. [ABSTRACT FROM AUTHOR]

The quantum key distribution (QKD) allows two parties to share a secret key by typically making use of a one-way quantum channel. However, the two-way QKD has its own unique advantages, which means the two-way QKD has become a focus recently. To improve the practical performance of the two-way QKD, we present a security analysis of a two-way QKD protocol based on the decoy method with heralded single-photon sources (HSPSs). We make use of two approaches to calculate the yield and the quantum bit error rate of single-photon and two-photon pulses. Then we present the secret key generation rate based on the GLLP formula. The numerical simulation shows that the protocol with HSPSs has an advantage in the secure distance compared with weak coherent state sources. In addition, we present the final secret key generation rate of the LM05 protocol with finite resources by considering the statistical fluctuation of the yield and the error rate. [ABSTRACT FROM AUTHOR]

A new experiment based on phase inversion of Pickering emulsions was carried out in a physical chemistry course. The emulsions were stabilized by surfactant-modified SiO[sub 2] particles. As the concentration of surfactant increased, the emulsions changed from oil-in-water type (O/W) to water-in-oil type (W/O) type, and then reverted to be O/W type again. This double phase inversion of emulsions proved to be an ideal indicator for the adsorption of surfactant on particle surfaces. The students gained preliminary lab skills and improved their understanding of the basic concepts in colloid and interface chemistry. In addition, students were encouraged to work out a mechanism to explain the phase inversion; this practice helped strengthen and improve their reasoning abilities. [ABSTRACT FROM AUTHOR]

The distribution of fractures in the underground rock mass is complex, so it is of great significance to study the parameter characteristics of fracture seepage for geothermal exploitation, land subsidence, and other fields. Based on the Weierstrass- Mandelbrot function, several X-shaped fracture models with different roughness are established, and the fracture seepage law under different roughness and inlet pressure is studied. At the same time, the center (cross-region) of the X-shaped fracture is selected as the research object, and the seepage difference characteristics of the cross-region under the two inlet modes of adjacent flow and convective flow are compared and analyzed. The results show that the outlet velocity of fracture fluid is inversely proportional to the fractal dimension and is directly proportional to the inlet pressure. [ABSTRACT FROM AUTHOR]

Context: Grape seed proanthocyanidin extract (GSPE) is effective in treating severe asthma (SA). Objective: To examine the relationship between Nrf2-miR-29b axis and SA, and to detect whether preventive use of GSPE relieves SA via it. Materials and methods: We recruited 10 healthy controls, 10 patients with non-severe asthma (nSA), and 9 patients with SA from February 2017 to December 2017. Peripheral blood mononuclear cells from these volunteers were extracted. A murine model of steroid-insensitive asthma was established in six-week-old female BALB/c mice that were sensitised and challenged with OVA, Al(OH)3 and LPS for 31 days. Mice in the treated groups were injected with DXM (5 mg/kg/d), with or without GSPE (100 mg/kg/d). Control group received PBS. We performed quantitative real-time PCR, western blot and luciferase reporter assay in animal and cell models. Results: SA group demonstrated significantly lower concentrations of Nrf2 protein, Nrf2 mRNA, and miR-29b than nSA group and control group. Conversely, higher levels of platelet derived growth factor C (PDGFC), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), and collagen type III alpha 1 (COL3A1) were measured in SA than in the other two groups. PDGFC, PIK3R1, and COL3A1 were the target genes of miR-29b. GSPE + DXM significantly elevated the expression of Nrf2 (+188%), Nrf2 mRNA (+506%), and miR-29b (+201%), and significantly reduced the expression of PDGFC (-72%), PIK3R1 (-40%), and COL3A1 (-65%) compared with OVA + LPS. Conclusions: Nrf2-miR-29b axis is involved in the pathogenesis of SA. GSPE, as an adjuvant drug, maybe a potential therapeutic agent for SA. [ABSTRACT FROM AUTHOR]

The SEP (Solar Energetic Particles) flux at 1au is an important index of space weather. Based on the parameterized Green function of the two-step SEP transport equation, we have simulated the SEP event on 2012 September 28, and calculated for the first time the SEP flux profiles observed by the GOES and STEREO double satellites for the same event. At the positions of GOES and STEREO-A, the calculated SEP peak value I max and the time to reach the peak value t max are well consistent with the observations. However, at the position of STEREO-B, there is a certain difference between our calculation and the observation, due to a large angular distance between the observed position and the SEP source, as well as the effect of unknown solar activities on the backside of the Sun. [ABSTRACT FROM AUTHOR]

A self-designed experimental installation for transient heat transfer in the modelling surrounding rock mass of high geothermal roadways was elaborated in this paper. By utilizing the new installation, the temperature variation rules in surrounding rock mass of the high geothermal roadway during mechanical ventilation were studied. The results show that the roadway wall temperature decreases dramatically at the early stage of ventilation, and the temperature at every position of the surrounding rock mass is decreasing constantly with time passing by. From roadway wall to deep area, the temperature gradually increases until reaching original rock temperature. The relationship between dimensionless temperature and dimensionless radius demonstrates approximately exponential function. Meanwhile, the temperature disturbance range in the simulated surrounding rock mass extends gradually from the roadway wall to deep area in the surrounding rock mass. Besides, as the air velocity increases, heat loss in the surrounding rock mass rises and the ratio of temperature reduction becomes larger, the speed of disturbance range expansion also gets faster. [ABSTRACT FROM AUTHOR]

Auxin-inducible degrons are a chemical genetic tool for targeted protein degradation and are widely used to study protein function in cultured mammalian cells. Here, we develop CRISPR-engineered mouse lines that enable rapid and highly specific degradation of tagged endogenous proteins in vivo. Most but not all cell types are competent for degradation. By combining ligand titrations with genetic crosses to generate animals with different allelic combinations, we show that degradation kinetics depend upon the dose of the tagged protein, ligand, and the E3 ligase substrate receptor TIR1. Rapid degradation of condensin I and II - two essential regulators of mitotic chromosome structure - revealed that both complexes are individually required for cell division in precursor lymphocytes, but not in their differentiated peripheral lymphocyte derivatives. This generalisable approach provides unprecedented temporal control over the dose of endogenous proteins in mouse models, with implications for studying essential biological pathways and modelling drug activity in mammalian tissues. [ABSTRACT FROM AUTHOR]