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Finite-difference (FD) method is the most extensively employed numerical modeling technique. Nevertheless, when using the FD method to simulate the seismic wave propagation, the large spatial or temporal sampling interval can lead to dispersion errors and numerical instability. In the FD scheme, the key factor in determining both dispersion errors and stability is the selection of the FD weights. Thus, How to obtain appropriate FD weights to guarantee a stable numerical modeling process with minimum dispersion error is critical. The FD weights computation strategies can be classified into three types based on different computational ideologies, window function strategy, optimization strategy, and Taylor expansion strategy. In this paper, we provide a comprehensive overview of these three strategies by presenting their fundamental theories. We conduct a set of comparative analyses of their strengths and weaknesses through various analysis tests and numerical modelings. According to these comparisons, we provide two potential research directions of this field: Firstly, the development of a computational strategy for FD weights that enhances stability; Secondly, obtaining FD weights that exhibit a wide bandwidth while minimizing dispersion errors. [ABSTRACT FROM AUTHOR]

Background: Metabolic dysfunction‐associated steatotic liver disease (MASLD) and alcohol consumption have both increased in recent years, and there is debate as to whether nonheavy alcohol use is safe in MASLD. We analyzed the association between different nonheavy alcohol use patterns and at‐risk liver fibrosis among individuals with MASLD. Methods: We conducted a cross‐sectional study of 1072 eligible National Health and Nutrition Examination Survey participants with MASLD who reported nonheavy alcohol consumption. We used vibration‐controlled transient elastography to define the primary outcome of at‐risk liver fibrosis as >8.2 kPa (stage F2‐F4). Multivariable logistic regression models were used to determine the association of different alcohol consumption patterns (average drinks/day, drinking days/week, weekly alcohol intake, type of alcoholic beverage) and at‐risk hepatic fibrosis, controlling for demographic/socioeconomic, lifestyle/dietary, and metabolic risk factors. Results: Exclusive liquor or cocktail drinkers had a 5.02‐fold odds of at‐risk fibrosis (95% CI: 1.15–21.95) compared with non‐drinkers when controlling for potential confounders. While consuming an average of 2 drinks/day, ≥3 drinking days/week, or 1–3 drinks/week appeared to have a lower association with at‐risk fibrosis when controlling for demographic/socioeconomic risk factors, the association was not present after controlling for lifestyle/dietary and metabolic risk factors. Conclusions: There is an association between exclusive liquor/cocktail consumption and at‐risk liver fibrosis in patients with MASLD who report nonheavy alcohol consumption. In a nationally representative sample of US adults with metabolic dysfunction‐associated steatotic liver disease (MASLD), exclusive liquor or cocktail consumption is associated with a 5.02‐fold increased risk of liver fibrosis among nonheavy alcohol users. Nonheavy alcohol use overall was not associated with F2 or greater liver fibrosis after adjusting for confounders. Our findings highlight the need to investigate subcategories of drinking behavior that may lead to liver fibrosis even among those without heavy drinking. [ABSTRACT FROM AUTHOR]

Introduction: The potential teratogenic risk of traditional Chinese medicine (TCM) is of widespread concern; however, related evidence is largely absent in humans. This study aimed to compare the prevalence of congenital malformations between pregnant women with and without TCM exposure. Material and methods: This was a multicenter prospective cohort study of 17 713 women who participated in a survey on periconceptional TCM exposure. Primary outcome was congenital malformations diagnosed from a survey conducted on the day 42 after delivery. Results: A total of 16 751 pregnant women with 273 congenital malformations were included in the analysis. Fetuses exposed to TCM had an increased risk of congenital malformations compared to those without exposure (odds ratio [OR] 2.10; 95% confidence interval [CI] 1.09-4.02) after controlling for potential confounders. There were significant associations with congenital malformations in women with early pregnant exposure (OR 2.04, 95% CI 1.00-4.20) and for those who received =2 TCM formulas (OR 5.84, 95% CI 1.44-23.65). Pre-pregnancy TCM exposure was significantly associated with an increased risk of congenital heart defects (OR 12.69; 95% CI 3.01-53.51). Conclusions: Periconceptional TCM exposure is associated with an increased risk of congenital malformation. This effect was cumulative and sensitive to periconceptional age. Therefore, TCM deserves more attention and should be used cautiously for pregnant women and those trying to become pregnant. [ABSTRACT FROM AUTHOR]

Alcohol sales and consumption have increased during the coronavirus disease 2019 pandemic, but their downstream effects on alcohol-related liver disease (ALD) are unclear. We analyzed inter-hospital escalation-of-care referrals to our tertiary care inpatient liver unit across 18 months through December 2020. There was a significant rise in severe ALD with recent unhealthy drinking in our regional community during the pandemic. [ABSTRACT FROM AUTHOR]

Background: Escalation of commitment is a common bias in human decision making. The present study examined (1) differences in neural recruitment for escalation and de-escalation decisions of prior investments, and (2) how the activations of these brain networks are affected by two factors that can arguably modulate escalation decisions: (i) self-responsibility, and (ii) framing of the success probabilities.Results: Imaging data were obtained from functional magnetic resonance imaging (fMRI) applied to 29 participants. A whole-brain analysis was conducted to compare brain activations between conditions. ROI analysis, then, was used to examine if these significant activations were modulated by two contextual factors. Finally, mediation analysis was applied to explore how the contextual factors affect escalation decisions through brain activations. The findings showed that (1) escalation decisions are faster than de-escalation decisions, (2) the corresponding network of brain regions recruited for escalation (anterior cingulate cortex, insula and precuneus) decisions differs from this recruited for de-escalation decisions (inferior and superior frontal gyri), (3) the switch from escalation to de-escalation is primarily frontal gyri dependent, and (4) activation in the anterior cingulate cortex, insula and precuneus were further increased in escalation decisions, when the outcome probabilities of the follow-up investment were positively framed; and activation in the inferior and superior frontal gyri in de-escalation decisions were increased when the outcome probabilities were negatively framed.Conclusions: Escalation and de-escalation decisions recruit different brain regions. Framing of possible outcomes as negative leads to escalation decisions through recruitment of the inferior frontal gyrus. Responsibility for decisions affects escalation decisions through recruitment of the superior (inferior) gyrus, when the decision is framed positively (negatively). [ABSTRACT FROM AUTHOR]

Purpose: This paper reports the panel discussion on the topic of artificial intelligence (AI) and robots in our lives. This discussion was held at the Digitization of the Individual (DOTI) workshop at the International Conference on Information Systems in 2019. Three scholars (in alphabetical order: Ting-Peng Liang, Lionel Robert and Suprateek Sarker) who have done AI- and robot-related research (to varying degrees) were invited to participate in the panel discussion. The panel was moderated by Manuel Trenz. Design/methodology/approach: This paper introduces the topic, chronicles the responses of the three panelists to the questions the workshop chairs posed and summarizes their responses, such that readers can have an overview of research on AI and robots in individuals' lives and insights about future research directions. Findings: The panelists discussed four questions with regard to their research experiences on AI- and robot-related topics. They expressed their viewpoints on the underlying nature, potential and effects of AI in work and personal life domains. They also commented on the ethical dilemmas for research and practice and provided their outlook for future research in these emerging fields. Originality/value: This paper aggregates the panelists' viewpoints, as expressed at the DOTI workshop. Crucial ethical and theoretical issues related to AI and robots in both work and personal life domains are addressed. Promising research directions to these cutting-edge research fields are also proposed. [ABSTRACT FROM AUTHOR]

Business Intelligence that applies data analytics to generate key information to support business decision making, has been an important area for more than two decades. In the last five years, the trend of “Big Data” has emerged and become a core element of Business Intelligence research. In this article, we review academic literature associated with “Big Data” and “Business Intelligence” to explore the development and research trends. We use bibliometric methods to analyze publications from 1990 to 2017 in journals indexed in Science Citation Index Expanded (SCIE), Social Science Citation Index (SSCI) and Arts & Humanities Citation Index (AHCI). We map the time trend, disciplinary distribution, high-frequency keywords to show emerging topics. The findings indicate that Computer Science and management information systems are two core disciplines that drive research associated with Big Data and Business Intelligence. “Data mining”, “social media” and “information system” are high frequency keywords, but “cloud computing”, “data warehouse” and “knowledge management” are more emphasized after 2016. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) is an essential element for the growth of both plants and bacteria. Low availability of Mg in agriculture can limit crop productivity and quality. In addition to direct effects on plant growth, limited Mg supply may also impact biological dinitrogen (N2) fixation in nodules formed from symbiotic interactions between legumes and rhizobial bacteria. To date, the physiological mechanisms involved in Mg‐dependent nodulation remain largely unknown. The objectives of this work were to assess how Mg supply affects nodule growth and development in symbiotic systems, and to test if any observed changes in nodule and soybean are correlated with Mg supply. Here, we found that external Mg supply enhanced nodule growth under nitrogen (N) limited conditions, and subsequently improved N2 fixation and soybean growth. Mg supply altered neither nodule structure nor Mg homeostasis, but remarkably promoted nodule enlargement, resulting in an increase in the number of big nodules. In addition, high Mg supply decreased starch and sucrose accumulation in leaves, and increased their concentrations in roots, which consequently enhanced carbohydrate import into the rhizobia infection zone of nodules. In this study, Mg was shown to promote nodule growth in soybean. This Mg‐promoted nodule growth is derived from Mg‐facilitated alteration of carbohydrate partitioning and transport into nodules. [ABSTRACT FROM AUTHOR]

Background: Drug resistance is one of the bottlenecks of cancer chemotherapy in the clinic. Polymeric nanomedicine is one of the most promising strategies for overcoming poor chemotherapy responses due to the multidrug resistance (MDR). Methods: In this study, a new polymer-based drug delivery system, poly(Lγ-glutamylglutamine)-doxorubicin (PGG-Dox) conjugate, was studied in both drug-induced resistant human breast cancer MDA-MB-231/MDR cells and their parent human breast cancer MDA-MB-231 cells. The effect of PGG on facilitating the growth inhibition of Dox against multidrug resistant cells were investigated by evaluating the cytotoxicity of PGG-Dox conjugate, PGG/Dox unconjugated complex and free Dox on both cells. The underlying mechanisms in resistant cells were further studied via the intracellular traffic studies. Results: Both conjugated and unconjugated PGG significantly increased Dox uptake, prolonged Dox retention and reduced Dox efflux in the MDA-MB-231/MDR cells. The PGG-Dox conjugate is taken up by tumor cells mainly by pinocytosis pathway, in which PGG-Dox conjugate-containing vesicles are formed and enter the cells. Conclusions: This study indicated that both polymer-drug conjugate and unconjugated complex are promising strategies of overcoming resistance of anti-tumor drugs. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an important micronutrient that mainly occurs in proteins in the form of selenocysteine and in tRNAs in the form of selenouridine. In the past 20 years, several genes involved in Se utilization have been characterized in both prokaryotes and eukaryotes. However, Se homeostasis and the associated regulatory network are not fully understood. In this study, we conducted comparative genomics and phylogenetic analyses to examine the occurrence of all known Se utilization traits in prokaryotes. Our results revealed a highly mosaic pattern of species that use Se (indifferent forms) in spite that most organisms do not use this element. Further investigation of genomic context of known Se-related genes in different organisms suggested novel candidate genes that may participate in Se metabolism in bacteria and/or archaea. Among them, a membrane protein, YedE, which contains ten transmembrane domains and shows distant similarity to a sulfur transporter, is exclusively found in Se-utilizing organisms, suggesting that it may be involved in Se transport. A LysR-like transcription factor subfamily might be important for the regulation of Sec biosynthesis and/or other Se-related genes. In addition, a small protein family DUF3343 is widespread in Se-utilizing organisms, which probably serves as an important chaperone for Se trafficking within the cells. Finally, we proposed a simple model of Se homeostasis based on our findings. Our study reveals new candidate genes involved in Se metabolism in prokaryotes and should be useful for a further understanding of the complex metabolism and the roles of Se in biology. [ABSTRACT FROM AUTHOR]

Background The inferior spikelets are defined to be those at portions where the grains receive less photosynthetic products during the seed development. The typical inferior spikelets are physically located on the proximal secondary branches in a rice panicle and traditionally characterized by a later flowering time and a slower grain-filling rate, compared to those socalled superior spikelets. Grains produced on the inferior spikelets are consequently underdeveloped and lighter in weight than those formed on the superior spikelets. MicroRNAs (miRNAs) are recognized as key players in regulating plant development through posttranscriptional gene regulations. We previously presented the evidence that miRNAs may influence grain-filling rate and played a role in determining the grain weight and yield in rice. Results In this study, further analyses of the expressed small RNAs in superior and inferior spikelets were conducted at five distinct developmental stages of grain development. Totally, 457 known miRNAs and 13 novel miRNAs were analyzed, showing a differential expression of 141 known miRNAs between superior and inferior spikelets with higher expression levels of most miRNAs associated with the superior than the inferior spikelets during the early stage of grain filling. Genes targeted by those differentially expressed miRNAs (i.e. miR156, miR164, miR167, miR397, miR1861, and miR1867) were recognized to play roles in multiple developmental and signaling pathways related to plant hormone homeostasis and starch accumulation. Conclusions Our data established a complicated link between miRNA dynamics and the traditional role of hormones in grain filling and development, providing new insights into the widely accepted concepts of the so-called superior and inferior spikelets in rice production. [ABSTRACT FROM AUTHOR]

Suppression subtractive hybridization ( SSH) was employed to identify candidate genes involved in red coloration in apple peel with the ultraviolet ( UV)-B-treated 'Mutsu'. After reverse Northern blotting verification, nearly 80 clones were successfully sequenced. Large portions of the expressed sequence tags ( ESTs) are well characterized anthocyanin biosynthesis-related genes, such as chalcone synthase ( 11A5), flavonol synthase ( 12F3), anthocyanidin synthase ( 11H5) and UDP-glycosyl transferase ( 14A12) whose presence proved the success of SSH. Eight ESTs were selected for quantitative real-time polymerase chain reaction analysis and their expressions were all elevated in 'Induction', further confirming the reliability of the SSH library. One EST, 11F4 ( CONSTITUTIVE PHOTOMORPHOGENIC 1: COP1) with putative function in light signal relay was further analyzed in 'Mutsu' and 'Tsugaru', along with MdHY5 ( ELONGATED HYPOCOTYL 5: the downstream target of COP1), MdMYB22 (a possible flavonol-specific activator under the regulation of HY5, belonging to the SG7/ PRODUCTION OF FLAVONOL GLYCOSIDES family) and MdMYBA. Results showed that MdCOP1, MdHY5, MdMYB22 and MdMYBA were all UV-B inducible genes and anthocyanin accumulation occurred after their increased expressions. Moreover, their expressions and anthocyanin content were enhanced under UV-B plus 17°C treatment. The presence of G box, a known consensus binding site of HY5, in the MdMYBA promoter region implicated that it could be regulated by MdHY5, which was verified by the result of the yeast one-hybrid analysis. Our data suggested that UV-B irradiation would induce the utmost upstream light signaling factor, MdCOP1, which activates MdHY5 signaling by binding to the promoter regions of MdMYBs, and finally leads to the red coloration of apple peels. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are upstream gene regulators of plant development and hormone homeostasis through their directed cleavage or translational repression of the target mRNAs, which may play crucial roles in rice grain filling and determining the final grain weight and yield. In this study, high-throughput sequencing was performed to survey the dynamic expressions of miRNAs and their corresponding target genes at five distinct developmental stages of grain filling. In total, 445 known miRNAs and 45 novel miRNAs were detected with most of them expressed in a developmental stage dependent manner, and the majority of known miRNAs, which increased gradually with rice grain filling, showed negatively related to the grain filling rate. Detailed expressional comparisons revealed a clear negative correlation between most miRNAs and their target genes. It was found that specific miRNA cohorts are expressed in a developmental stage dependent manner during grain filling and the known functions of these miRNAs are involved in plant hormone homeostasis and starch accumulation, indicating that the expression dynamics of these miRNAs might play key roles in regulating rice grain filling. [ABSTRACT FROM AUTHOR]

Decision making in virtual teams is gaining momentum due to globalization, mobility of employees, and the need for collective and rapid decision making by members who are in different locations. These factors resulted in a proliferation of virtual team software support tools for decision making, the latest of which is social software (also known as collaboration 2.0), which includes tools such as wikis, blogs, microblogs, discussion forums, and social networking platforms. This paper describes the potential use of collaboration 2.0 software for improving the process and the specific tasks in virtual group decision making. The paper proposes a framework for exploring the fitness between social software and the major activities in the group decision making process and how such tools can be successfully adopted. Specifically, we use a fit-viability model to help assessing whether social software fit a decision task and what organizational factors are important for such tools to be effective. Representative research issues related to the use of such tools are also presented. [ABSTRACT FROM AUTHOR]

mobile services become more popular and people can use them virtually anywhere, research on the effect of use contexts is gaining more attention. This research presents results from a study of continuous use of mobile services in different use contexts as defined by task and consumption place. Using mobile games as an example, the authors proposed a research model that augments current technology adoption theories to fit the hedonic nature of mobile games. The results from conducting an online survey indicate that contextual factors have significant moderating effect on the intention to play mobile games. The diverse lifestyles of users also have different attitudes and concerns regarding using mobile services. The findings suggest that service providers need to take into account the impact of use contexts and the needs of specific users when they design mobile services. [ABSTRACT FROM AUTHOR]

From one perspective, diversity leads to an increase in the knowledge and viewpoints that adds to the creativity of the solution and methods during a software development project. From another perspective, diversity adds to the conflict in a project team, which detracts significantly from the desired results. This contradiction may be best explained by an examination of different forms of diversity. This study reports a model that considers informational diversity, in the form of a larger variety of background knowledge, in the system development context. Learning and information theories dictate that conflict related to the completion of tasks will increase under informational diversity. Task-related conflict should, in turn, create learning opportunities, which will provide the spark needed to improve the quality of the software generated by a project team. A team level analysis of survey data from 299 members of 75 development teams confirms these relationships. The promotion of learning leverages the benefits of informational diversity and serves as a mediator between task-related conflict and software quality. [ABSTRACT FROM AUTHOR]

A combined grid-connection/power-factor-correction technique for a photovoltaic (PV) system is proposed in this letter. A maximum power point tracking dc/dc converter served as a charger for the battery bank. A bidirectional inverter is applied as a generator/discharger during daytime, supplying power to the load. The inverter can also be used as a charger to maintain the minimum required voltage level of the batteries when the PV power is insufficient. Experiments on a 1-kW PV system show satisfactory results of the power management and the unity power factor at the utility side. [ABSTRACT FROM AUTHOR]

Since models play a critical role in human decision processes, model management is considered a very important function for decision support. This article examines how model management systems can be designed to support group problem-solving. First, basic concepts of model management and functional requirements for group model management systems are described. Then, an architecture for group model management systems design is presented. Finally, major implementation issues are discussed. [ABSTRACT FROM AUTHOR]

(1− x)(K0.48Na0.52)(Nb0.95Ta0.05)O3– xLiSbO3 [(1− x)KNNT− xLS] lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method. A morphotropic phase boundary (MPB) between orthorhombic and tetragonal phases was identified in the composition range of 0.03< x<0.05. The ceramics near the MPB exhibit a strong compositional dependence and enhanced electrical properties. The (1− x)KNNT– xLS ( x=0.04) ceramics exhibit good electrical properties ( d33=250 pC/N, kp=45.1%, k t=46.3%, Tc=348°C, T o− t=74°C, Pr=25.9 μC/cm2, Ec=10.7 kV/cm, ℇr∼1352, tan δ∼3%). These results show that (1− x)KNNT– xLS ceramic is a promising lead-free piezoelectric material. [ABSTRACT FROM AUTHOR]

Background: The opioid crisis has led to an increase in hepatitis C virus‐positive donors in the past decade. Whereas historically hepatitis C seropositive organs were routinely discarded, the advent of direct‐acting antiviral agents has notably expanded the utilization of organs from donors with hepatitis C. There has been growing experience with liver transplantation (LT) from hepatitis C seropositive donors to hepatitis C seropositive recipients. However, data remain limited on LT from hepatitis C seropositive or hepatitis C ribonucleic acid positive donors to hepatitis C seronegative recipients. Methods: We performed a retrospective study of 26 hepatitis C seronegative recipients who received hepatitis C seropositive donor livers followed by preemptive antiviral therapy with direct‐acting antiviral treatment at the Johns Hopkins Hospital Comprehensive Transplant Center from January 1, 2017, to August 31, 2019. Results: Twenty‐five of the 26 recipients are alive with proper graft function; 20 of them received livers from hepatitis C nucleic acid testing positive donors. All 12 recipients who completed their direct‐acting antiviral courses and have reached sufficient follow‐up for sustained virologic response have achieved sustained virologic response. Nine of our recipients have either completed direct‐acting antiviral treatment without sufficient follow‐up time for sustained virologic response or are undergoing direct‐acting antiviral treatment. One patient is awaiting antiviral treatment initiation pending insurance approval. Of note, 11 of 12 patients with sustained virologic response received a hepatitis C nucleic acid testing positive donor liver. Conclusion: Hepatitis C seronegative patients who receive a hepatitis C seropositive or hepatitis C nucleic acid testing positive liver allograft can enjoy good short‐term outcomes with hepatitis C cure following direct‐acting antiviral treatment. [ABSTRACT FROM AUTHOR]

Dynamic programming is difficult to apply to large-scale Bayesian network structure learning. In view of this, this article proposes a BN structure learning algorithm based on dynamic programming, which integrates improved MMPC (maximum-minimum parents and children) and MWST (maximum weight spanning tree). First, we use the maximum weight spanning tree to obtain the maximum number of parent nodes of the network node. Second, the MMPC algorithm is improved by the symmetric relationship to reduce false-positive nodes and obtain the set of candidate parent-child nodes. Finally, with the maximum number of parent nodes and the set of candidate parent nodes as constraints, we prune the parent graph of dynamic programming to reduce the number of scoring calculations and the complexity of the algorithm. Experiments have proved that when an appropriate significance level α is selected, the MMPCDP algorithm can greatly reduce the number of scoring calculations and running time while ensuring its accuracy. [ABSTRACT FROM AUTHOR]

This article discusses the clinical outcomes of endoscopic submucosal dissection (ESD) for superficial esophageal neoplasia (SEN) in patients with cirrhosis and esophageal varices. The study found that ESD was safe and effective in achieving complete resection of SEN in these patients, with high rates of successful removal. The results suggest that ESD may be a viable treatment option for this patient population. Another study discussed in the document found that ESD was feasible and safe in cirrhotic patients with SEN near esophageal varices, with high rates of successful removal and low rates of complications. The study suggests that ESD can be a potential treatment option for cirrhotic patients with SEN, even in the presence of esophageal varices. [Extracted from the article]

Background: Cadmium (Cd), a common environmental heavy metal and endocrine disruptor, is known to exert toxic effects on the testes. However, the mechanisms accounting for its toxicity in mature spermatozoa remain unclear. Methods: Adult male C57BL/6 mice were orally administered with CdCl2 for 5 weeks at 3 mg⋅kg-1⋅day-1. Additionally, mouse spermatozoa were incubated in vitro with different doses of CdCl2 (0, 10, 50, 250 µM). Several sperm functions including the sperm motility, viability and acrosome reaction (AR) ratio were then examined. Furthermore, the current and expression levels of both the sperm-specific Ca2+ channel (CatSper) and the sperm-specific K+ channel (KSper) were evaluated by patch-clamping and western blotting, respectively. Results: Our data showed that the motility, viability and AR of sperm exposed to cadmium significantly decreased in vivo and in vitro. Interestingly, these changes were correlated with changes in CatSper but not KSper. Conclusion: The findings indicate sperm dysfunction during both chronic and acute cadmium exposure as well as a specific role for CatSper in the reproductive toxicity of cadmium. [ABSTRACT FROM AUTHOR]

Background: Alkaline/neutral invertase (A/N-INV), an enzyme that hydrolyzes sucrose irreversibly into glucose and fructose, is essential for normal plant growth,development, and stress tolerance. However, the physiological and/or molecular mechanism underpinning the role of A/N-INV in abiotic stress tolerance is poorly understood. Results: In this report, an A/N-INV gene (PtrA/NINV) was isolated from Poncirus trifoliata, a cold-hardy relative of citrus, and functionally characterized. PtrA/NINV expression levels were induced by cold, salt, dehydration, sucrose, and ABA, but decreased by glucose. PtrA/NINV was found to localize in both chloroplasts and mitochondria. Overexpression of PtrA/NINV conferred enhanced tolerance to multiple stresses, including cold, high salinity, and drought, as supported by lower levels of reactive oxygen species (ROS), reduced oxidative damages, decreased water loss rate, and increased photosynthesis efficiency, relative to wild-type (WT). The transgenic plants exhibited higher A/N-INV activity and greater reducing sugar content under normal and stress conditions. Conclusions: PtrA/NINV is an important gene implicated in sucrose decomposition, and plays a positive role in abiotic stress tolerance by promoting osmotic adjustment, ROS detoxification and photosynthesis efficiency. Thus, PtrA/NINV has great potential to be used in transgenic breeding for improvement of stress tolerance. [ABSTRACT FROM AUTHOR]

Previous research has proposed different types for and contingency factors affecting information technology governance. Yet, in spite of this valuable work, it is still unclear through what mechanisms IT governance affects organizational performance. We make a detailed argument for the mediation of strategic alignment in this process. Strategic alignment remains a top priority for business and IT executives, but theory-based empirical research on the relative importance of the factors affecting strategic alignment is still lagging. By consolidating strategic alignment and IT governance models, this research proposes a nomological model showing how organizational value is created through IT governance mechanisms. Our research model draws upon the resource-based view of the firm and provides guidance on how strategic alignment can mediate the effectiveness of IT governance on organizational performance. As such, it contributes to the knowledge bases of both alignment and IT governance literatures. Using dyadic data collected from 131 Taiwanese companies (cross-validated with archival data from 72 firms), we uncover a positive, significant, and impactful linkage between IT governance mechanisms and strategic alignment and, further, between strategic alignment and organizational performance. We also show that the effect of IT governance mechanisms on organizational performance is fully mediated by strategic alignment. Besides making contributions to construct and measure items in this domain, this research contributes to the theory base by integrating and extending the literature on IT governance and strategic alignment, both of which have long been recognized as critical for achieving organizational goals. [ABSTRACT FROM AUTHOR]

The paper was to analyze the differences of genes and genome methylation between ‘lane late’ navel orange and it’s bud sport pumpkin-like navel orange, and to reveal the causes of bud sport. [Methods] Amplification fragment length polymorphism （AFLP） and methylation sensitive amplification polymorphism （MSAP） were used to analyze the differences in genes and genome methylation of ‘lane late’ navel orange and its bud sport pumpkin-like navel orange. [Results] Gene mutation occurred between the ‘lane late’ navel orange and its bud sport pumpkin-like navel orange. A total of 15 differential bands were obtained by AFLP markers, and the percentage of polymorphic bands was 6.000 0%. Meantime, 10 differential bands were obtained by MSAP markers, and the percentage of polymorphic bands was 5.464 5%. The semi methylation rate and permethylation rate of ‘lane late’ navel orange were higher than that of pumpkin-like navel orange, that is, pumpkin-like navel orange had demethylation （demethylation ratio was 1.639 3%）. [Conclusions] It is proved at the DNA level that the emergence of bud sport pumpkin-like navel orange is due to gene mutation, and the DNA methylation level of the bud sport material has also changed. This study lays a foundation for further exploring the mechanism of bud sport. [ABSTRACT FROM AUTHOR]

Innovations associated with information and communication technology (ICT) have opened up new opportunities for the global economy and ushered in the age of e-commerce. Our objective in this research is to explore the role of Internet-based selling technology, which acts as technology infrastructure for B2C e-commerce growth at the country level. This study proposes the use of a new hybrid growth theory approach as the theoretical basis for examining exogenous and endogenous factors that influence e-commerce growth over time. We estimate three different models to evaluate their explanatory capabilities. We investigate a panel-corrected feasible generalized least squares regression that incorporates the direct effects of country-level variables. We also specify an endogeneity-adjusted two-stage least squares model and estimate it with an embedded technology adoption function in a simultaneous equation model. This permits the analysis of the relevance of IT infrastructure, as well as reverse causality between e-commerce growth and Internet-based selling technology. We test these models using archival data for four different regions, based on either 24 or 42 countries around the world, depending on the data requirements of the models. Our empirical tests evaluate quasi-production environmental inputs, in which technology determines the environment of production of e-commerce services. Our main finding is that both endogenous variables (e.g., Internet user penetration, capital invested in telecommunication) and exogenous variables (international openness) drive the GDP-normalized level of B2C e-commerce revenues over time. A second main finding is that it is useful to include an embedded technology adoption function in a modeling specification for growth, since growth is founded on the availability of relevant IT infrastructure that is made possible by the availability of venture capital. In addition, B2C e-commerce revenue growth and venture capital also contribute to the adoption of Internet-based selling technology. We discuss our overall approach for the interpretation of the strength of our main findings, as well as the policy implications, and why our hybrid growth theory approach is useful. [ABSTRACT FROM AUTHOR]

Polyamines, small aliphatic polycations, have been suggested to play key roles in a number of biological processes. In this paper, attempts were made to investigate the possibility of improving dehydration tolerance of citrus in vitro plants by exogenous application of spermine (Spm). ‘Red Tangerine’ (Citrus reticulata Blanco) in vitro plants pretreated with 1 mM Spm exhibited less wilted phenotype and lower water loss and electrolyte leakage than the control under dehydration. Spm-pretreated plants contained higher endogenous polyamine content during the course of the experiment relative to the control, particularly at the end of dehydration, coupled with higher expression levels of ADC and SPMS. Histochemical staining showed that the Spm-pretreated leaves were stained to a lower extent than those without Spm pretreatment, implying generation of less reactive oxygen species (ROS). On the contrary, activities of peroxidase (POD) and superoxide dismutase (SOD) in the Spm-pretreated samples were higher than the control at a given time point or during the whole experiment, suggesting that Spm exerted a positive effect on antioxidant systems. In addition, significantly smaller stomatal aperture size was observed in Spm-pretreated epidermal peels, which showed that stomatal closure was promoted by polyamines. All of these data suggest that Spm pretreatment causes accumulation of higher endogenous polyamines and accordingly leads to more effective ROS scavenging (less tissue damage) and stimulated stomatal closure (lower water loss) upon dehydration, which may function collectively to enhance dehydration tolerance. [ABSTRACT FROM PUBLISHER]

This paper presents a photovoltaic (PV) system parallel connected to an electric power grid with a power factor corrector (PFC) for supplying the dc loads. The operation principles and design considerations for the presented PV system are analyzed and discussed. The balanced distribution of the power flows between the utility and the PV panels is achieved automatically by regulating the output dc voltage of the PFC. Experimental results are shown to verify the feasibility of the proposed topology, which can effectively transfer the tracked maximum power from the PV system to the dc load, while the unity power factor is obtained at the utility side. [ABSTRACT FROM AUTHOR]

Abstract: Data mining consists of a set of powerful methods that have been successfully applied to many different application domains, including business, engineering, and bioinformatics. In this paper, we propose an innovative approach that uses genetic algorithms to mine a set of temporal behavior data output by a biological system in order to determine the kinetic parameters of the system. Analyzing the behavior of a biological network is a complicated task. In our approach, the machine learning method is integrated with the framework of system dynamics so that its findings are expressed in a form of system dynamics model. An application of the method to the cell division cycle model has shown that the method can discover approximate parametric values of the system and reproduce the input behavior. [Copyright &y& Elsevier]

The article presents a study that explores the deep exploration of random forest model boosts the interpretability of machine learning studies of complicated immune responses and lung burden of nanoparticles. It mentions that development of machine learning provides solutions for predicting the complicated immune responses and pharmacokinetics of nanoparticles (NPs) in vivo.

To explore the differences in hoarding strategies of rodents for different seeds in various seasons, we labeled and released the seeds of Pinus koraiensis, Corylus mandshurica, Quercus mongolica and Prunus sibirica in temperate forests of Northeast China and investigated the fate of the seeds in spring and autumn. The analysis showed that the hoarding strategies of the rodents varied substantially between seasons. The seeds were consumed faster in the spring than in the autumn. More than 50% of the seeds in the two seasons were consumed by the 16th day. It took 36 days to consume 75% of the seeds in the spring and 44 days in the autumn. The rate of consumption of the seeds in the spring was greater than in the autumn, and the rate of spread of the seeds was greater in the autumn. The distances of removal for the consumption and dispersal of seeds in the spring (3.26 ± 3.21 m and 4.15 ± 3.52 m, respectively) were both shorter than those in the autumn (3.74 ± 3.41 m and 4.87 ± 3.94 m, respectively). In addition, the fate of different seeds varied significantly owing to differences in hoarding strategies. The seeds of the three preferred species, P. koraiensis, C. mandshurica, and Q. mongolica, were quickly consumed. More than 90% of the seeds of these species were consumed. Only 21% of Pr. sibirica seeds were slowly consumed, and the two seasons had the same seed consumption rate patterns: the consumption rate of P. koraiensis seeds was the highest, followed by C. mandshurica, then Q. mongolica, and finally Pr. sibirica. The median removal times of the two seasons were different, but the rules were the same: P. koraiensis was the shortest, followed by C. mandshurica, and the third was Q. mongolica. In both seasons, the most predated in situ seeds were those of P. koraiensis; the most hoarded seeds were those of C. mandshurica, and the most unconsumed seeds were those of Pr. sibirica. [ABSTRACT FROM AUTHOR]

Apodemus peninsulae, a dominant rodent species in temperature forests of northeastern China, is a model animal to explore the ecological functions of reciprocal coevolution of animals and plants. From August to October 2016, 24 infra-red cameras were installed to study the feeding behavior and activity patterns of A. peninsulae in its natural environment. By analyzing 5618 video records, we found that feeding behavior, followed by motor and sentinel behaviors, was their main activity. In the behavior spectra, motor behavior (creep, walk, and skip), feeding behavior (forage, feeding, transport, hoarding, and clean), and sentinel behavior (alert, flee, banishment, and coexistence) accounted for 57.96%, 40.36%, and 1.68% of their behavior, respectively. The peak of feeding behavior occurred between 18:00 and 23:00, and feeding behavior frequency, duration, and activity rhythms differ among August to October. Furthermore, activity was the greatest after sunset and before sunrise, indicating a nocturnal lifestyle; however, from August to October, the start time of the activity was earlier, and the end time was later than usual. On average, mice spent 21.6 ± 11.6 times/night feeding, with a duration of 63.58 ± 98.36 s; while they spent less time in foraging, 39.05 ± 51.63 s. We found a significant difference in feeding and foraging frequency, with mice spending on average 10.84 ± 9.85 times/night and 9.23 ± 11.17 times/night, respectively. Our results show that feeding and foraging behavior is also influenced by light intensity, suggesting a preference for crepuscular periods of the day. Infra-red cameras are very useful in detecting activity patterns of animals that are not easily observable; these cameras are able to capture a large amount of valuable information for research into ecological functions. [ABSTRACT FROM AUTHOR]

Protein corona formation is critical for the design of ideal and safe nanoparticles (NPs) for nanomedicine, biosensing, organ targeting, and other applications, but methods to quantitatively predict the formation of the protein corona, especially for functional compositions, remain unavailable. The traditional linear regression model performs poorly for the protein corona, as measured by R2 (less than 0.40). Here, the performance with R2 over 0.75 in the prediction of the protein corona was achieved by integrating a machine learning model and meta-analysis. NPs without modification and surface modification were identified as the two most important factors determining protein corona formation. According to experimental verification, the functional protein compositions (e.g., immune proteins, complement proteins, and apolipoproteins) in complex coronas were precisely predicted with good R² (most over 0.80). Moreover, the method successfully predicted the cellular recognition (e.g., cellular uptake by macrophages and cytokine release) mediated by functional corona proteins. This workflow provides a method to accurately and quantitatively predict the functional composition of the protein corona that determines cellular recognition and nanotoxicity to guide the synthesis and applications of a wide range of NPs by overcoming limitations and uncertainty. [ABSTRACT FROM AUTHOR]

Purpose: Several RAB family genes have been studied extensively and proven to play pivotal roles in the occurrence and development of certain cancers. Here, we explored commonly expressed RAB family genes in humans and their prognostic significance using bioinformatics, and then identified potential biomarkers of breast invasive carcinoma (BRCA). Materials and methods: The prognostic values (overall survival) of RAB family genes in BRCA were obtained using Gene Expression Profiling Interactive Analysis (GEPIA). The expression patterns of RAB family genes and their relationships with clinicopathological parameters in BRCA were measured using the ONCOMINE and UALCAN databases, respectively. Genetic mutations and survival analysis were investigated using the cBio Cancer Genomics Portal (c-BioPortal). Interacting genes of potential biomarkers were identified using STRING, and functional enrichment analyses were performed using FunRich v3.1.3. Results: In total, 64 RAB genes were identified and analyzed in our study. Results showed that RAB1B, RAB2A, and RAB18 were up-regulated and significantly associated with poor overall survival in BRCA. Furthermore, their higher expression was positively correlated with clinicopathological parameters (e.g. cancer stage and nodal metastasis status). DNA copy number amplifications and mRNA up-regulationwere the main genetic mutations, and the altered group showed significantly poorer overall survival compared with the unaltered group. Functional enrichment analysis of RAB1B, RAB2A, and RAB18 indicated they were closely involved in GTPase activity. Conclusions: RAB1B, RAB2A, and RAB18 were up-regulated and significantly correlated with poor prognosis in BRCA. Thus, they could be applied as novel biomarkers of BRCA in future studies. [ABSTRACT FROM AUTHOR]

IL-1R-associated kinases (IRAK) are important regulators in the TLR/IL-1R pathways, but their function appears inconsistent between Drosophila, bony fishes, and vertebrates. This causes a difficulty to understand the IRAK functions. As a step to reveal the evolution of IRAKs, in this study, we performed comparative and functional analysis of IRAKs by exploiting the amphioxus, a pivotal taxon connecting invertebrates and vertebrates. Sequence and phylogenetic analysis indicated three major IRAK lineages: IRAK1/2/3 is a vertebrate-specific lineage, IRAK4 is an ancient lineage conserved between invertebrate and vertebrates, and Pelle is another ancient lineage that is preserved in protostomes and invertebrate deuterostomes but lost in vertebrate deuterostomes. Pelle is closer neither to IRAK4 nor to IRAK1/2/3, hence suggesting no clear functional analogs to IRAK1/2/3 in nonvertebrates. Functional analysis showed that both amphioxus IRAK4 and Pelle could suppress NF-kB activation induced by MyD88 and TRAF6, which are unlike mammalian and Drosophila IRAKs, but, surprisingly, similar to bony fish IRAK4. Also unlike Drosophila IRAKs, no interaction was detected between amphioxus IRAK4 and Pelle, although both of them were shown capable of binding MyD88. These findings, together with previous reports, show that unlike other signal transducers in the TLR/IL-1R pathways, such as MyD88 and TRAF6, the functions of IRAKs are highly variable during evolution and very specialized in different major animal taxa. Indeed, we suggest that the functional variability of IRAKs might confer plasticity to the signal transduction of the TLR/IL-1R pathways, which in return helps the species to evolve against the pathogens. [ABSTRACT FROM AUTHOR]

This paper presents a red, green, and blue (RGB) light-emitting diode (LED) backlight circuit for liquid crystal display (LCD) panels. Some studies have been conducted to devise dimming methods that regulate the RGB LED currents. In this paper, design considerations for the RGB LED backlight are presented. A laboratory prototype for 20-in panels is implemented and tested. The color gamut of an LCD panel with the designed RGB LED backlight is measured and discussed. The experimental results of the laboratory prototype are also shown to verify feasibility of the findings. [ABSTRACT FROM AUTHOR]

A major cause of failure in chemotherapy is drug resistance of cancer cells. Exosomes have been introduced to spread chemoresistance through delivering miRNAs. However, a systematic evaluation of the exosomal miRNA expression profiles responsible for chemoresistance is still lacking. In the present study, miRNA signature differentially expressed in exosomes derived from adriamycin-resistant (A/exo) and parental breast cancer cells (S/exo) were analyzed by microarray and the results were confirmed by PCR. A total of 309 miRNAs were increased and 66 miRNAs were decreased significantly in A/exo compared with S/exo. Specifically, 52 novel miRNAs with increased expression levels >16.0-fold in A/exo were identified. After prediction of target genes for 13 of 52 selected novel miRNAs, pathway analysis, gene ontology (GO) terms, and protein-protein interactions (PPIs) were constructed. The results implied that these selected exosomal miRNAs inhibited target genes involved in transcriptional misregulation in cancer, MAPK, and Wnt signaling pathways. Functional enrichment analysis demonstrated that the target genes were mainly responsible for protein phosphorylation, transcription regulation, molecular binding, and kinase activity. In summary, the current bioinformatics study of exosomal miRNAs may offer a new understanding into mechanisms of chemoresistance, which is helpful to find potential exosomal miRNAs to overcome drug insensitivity in future breast cancer treatment. [ABSTRACT FROM AUTHOR]

In plants and microorganisms, aspartate kinase (AK) catalyzes an initial commitment step of the aspartate family amino acid biosynthesis. Owing to various structural organizations, AKs from different species show tremendous diversity and complex allosteric controls. We report the crystal structure of AK from Pseudomonas aeruginosa (PaAK), a typical α2β2 hetero-tetrameric enzyme, in complex with inhibitory effectors. Distinctive features of PaAK are revealed by structural and biochemical analyses. Essentially, the open conformation of Lys-/Thr-bound PaAK structure clarifies the inhibitory mechanism of α2β2-type AK. Moreover, the various inhibitory effectors of PaAK have been identified and a general amino acid effector motif of AK family is described. [ABSTRACT FROM AUTHOR]

Background: microRNAs (miRNAs) are important regulators in plant growth and development. miR159 is a conserved miRNA among different plant species and has various functions in plants. Studies on miR159 are mostly done on model plant, Arabidopsis thaliana. In rice, studies on miR159 were either based upon genome-wide expression analyses focused upon responses to different nitrogen forms and abiotic stress or upon phenotypic studies of transgenic plants overexpressing its precursor. STTM (Short Tandem Target Mimic) is an effective tool to block the activity of endogenous mature miRNA activity in plant. Therefore, specific roles of miR159 in rice could be explored by down regulating miR159 through STTM. Results: In this study, expression of mature miR159 was successfully suppressed by STTM which resulted in the increased expressions of its two targets genes, OsGAMYB and OsGAMYBL1 (GAMYB-LIKE 1). Overall, STTM159 plants exhibited short stature along with smaller organ size and reduction in stem diameter, length of flag leaf, main panicle, spikelet hulls and grain size. Histological analysis of stem, leaf and mature spikelet hull showed the reduced number of small vascular bundles (SVB), less number of small veins (SV) between two big veins (LV) and less cell number in outer parenchyma. Gene Ontology (GO) enrichment analysis of differentially expressed genes between wild type plants and STTM159 transgenic plants showed that genes involved in cell division, auxin, cytokinin (CK) and brassinosteroids (BRs) biosynthesis and signaling are significantly down-regulated in STTM159 plants. Conclusion: Our data suggests that in rice, miR159 positively regulates organ size, including stem, leaf, and grain size due to the promotion of cell division. Further analysis from the RNA-seq data showed that the decreased cell divisions in STTM159 transgenic plants may result, at least partly from the lower expression of the genes involved in cell cycle and hormone homeostasis, which provides new insights of rice miR159-specific functions. [ABSTRACT FROM AUTHOR]

The durability and sustainability of concrete structures is a prime socioeconomic concern of contemporary society. The lifecycle of these structures is typically determined by the rate of moisture ingress, in which dissolved and unwanted substances are transported into the structure. Therefore finding a sufficient means to measure these rates is of utmost importance. A sorptivity testing scheme as outlined by a commonly used standard can be a useful means of measuring how quickly liquid can be transported unidirectionally through concrete samples in the laboratory. Currently the standard prescribes that disc specimens 100 mm in diameter and 50-mm thick be sealed in such a manner to ensure unidirectional flow through one, unsealed face of the sample, while all other surfaces are appropriately sealed. However the standard does not specify how this seal is to be achieved. Furthermore, differing methods have yielded a likewise array of varied results, which may not be representative of the true sorptivity. The objective of this paper is to propose a simple but effective means of sealing the specimens that will yield more consistent results, which are more representative of the actual absorption properties of the concrete. This was accomplished by studying the performance of electrical insulation tape and cellophane (as suggested in the standard) against paraffin wax using three different mixture designs, as follows: (1) involving normal strength concrete without air entrainment, (2) a normal strength concrete mixture with air entrapment, and (3) self-consolidating concrete without air entrapment. The prepared specimens were subjected to various freeze-thaw cycling periods, conditioned, and then tested for sorptivity. Batches of samples were exposed to freeze-thaw cycling periods of 0, 50, 100, 150, 200, and 300 cycles. Within each group of samples, half of the specimens were sealed with electrical tape and cellophane, and the other half were sealed with paraffin wax in order to conduct sorptivity testing. Specimens coated in wax typically exhibited lower absorption values than those wrapped in tape. Furthermore, the tape would not adhere perfectly with the concrete at the edge formed by the cylindrical wall and the exposed surface, resulting in increased sorptivity values. Statistical analysis was done on the rates of early-age (0-6 h) and late-age (1-8 days) sorptivity by using the F-test to examine variability (with an 80% confidence interval) and the student-t test was used to evaluate the significance of differences in sample means. Generally, sorptivity rates were higher for taped samples than those for waxed samples. These results further reinforced visual observations. The waxed samples yielded more reliable results primarily because they did not absorb moisture artificially along the sides in the manner as observed in the taped specimens. Moreover, the paraffin wax sealant method also resulted in less variability within test results. Therefore it was believed that the wax facilitated more representative results of the true sorptivity. It was suggested that the procedures of the common standard discussed in this paper should be refined such that the sealing of test specimens should be done with the use of paraffin wax, or some other similar substance, such as silicone, which is impermeable and readily available commercially. [ABSTRACT FROM AUTHOR]

Thedesign, synthesis, and SAR studies of novel inhibitors of HCVNS4B based on the imidazo[2,1-b]thiazole scaffoldwere described. Optimization of potency with respect to genotype 1bresulted in the discovery of two potent leads 26f(EC50= 16 nM) and 28g(EC50= 31 nM).The resistance profile studies revealed that 26fand 28gtargeted HCV NS4B, more precisely the second amphipathicα helix of NS4B (4BAH2). Cross-resistance between our 4BAH2inhibitors and other direct-acting antiviral agents targeting NS3/4A,NS5A, and NS5B was not observed. For the first time, the synergismof a series of combinations based on 4BAH2 inhibitors was evaluated.The results demonstrated that our 4BAH2 inhibitor 26fwas synergistic with NS3/4A inhibitor simeprevir, NS5A inhibitordaclatasvir, and NS5B inhibitor sofosbuvir, and it could also reducethe dose of these drugs at almost all effect levels. Our study suggestedthat favorable effects could be achieved by combining 4BAH2 inhibitorssuch as 26fwith these approved drugs and that new all-oralantiviral combinations based on 4BAH2 inhibitors were worth developingto supplement or even replace current treatment regimens for curingHCV infection. [ABSTRACT FROM AUTHOR]

The article discusses the regulation of autophagy by the ZBTB16-Cullin3-Roc1 ubiquitin ligase complex. It focuses on a mouse model of Huntington's disease and discusses that the activation of autophagy protects against behavior dysfunction. It also presents a pharmacological strategy for activating autophagy in the central nervous system (CNS).

[Display omitted] • An experimental strategy is proposed to evaluate the energy performance of MOF-based CO 2 adsorbents. • The energy property of UiO-66-X MOFs with various functional groups has been reasonably evaluated using this strategy. • An inverse proportional relationship between parasitic energy and working capacity is found for UiO-66-X MOFs. • It is found that the key determinants for the regeneration energy efficiency are the specific heat capacity of adsorbents and CO 2 working capacity. Recently, metal–organic frameworks (MOFs) have attracted great interest in the field of carbon capture and storage (CCS) as promising carbon dioxide (CO 2) adsorbents. The energy performance in relation to the regeneration process is a crucial factor when screening for suitable CCS MOF adsorbents. However, few experimental methods have been reported for evaluating the energy requirements for their regeneration. Herein, we proposed an experimental strategy to investigate the energy performance of MOF adsorbents for CO 2 capture in the temperature swing adsorption (TSA) process using a combination of calorimetry and thermal analysis method. Five well-characterized isomorphic zirconium-based MOFs (University of Oslo 66-X, where X = H, NH 2 , (OH) 2 , C 4 H 4 , or NO 2) were reliably evaluated using this strategy. The energy parameters related to regeneration, including specific heat capacities, thermodynamic functions, desorption temperatures, regeneration energy, CO 2 working capacities, and parasitic energy, were accurately determined for these MOFs. The results indicated that the key determinants for the regeneration energy efficiency of CO 2 adsorbents were their specific heat capacities and CO 2 working capacities during a TSA cycle. More importantly, the proposed strategy may provide a feasible and effective experimental approach to study and evaluate the potential of adsorbents for CO 2 capture. [ABSTRACT FROM AUTHOR]

Three new compounds, including one daphnane diterpene (1), one sesquiterpene (6), and one lignan (7) have been isolated from the Stellera chamaejasme L., together with five other known compounds, including four daphnane diterpenenoids (2-5) and one lignan (8). The structures of the new compounds were elucidated by spectroscopic analysis. The cytotoxicities of compounds 1-8 towards human lung adenocarcinoma cells (A549 cells) were evaluated using a sulforhodamine B assay. All of the compounds displayed significant cytotoxicity, with IC50 values in the ranging of 0.2nM to 2.0μM. Mechanistic studies revealed that the antitumor activities of compounds 1-3 and 7 were derived from their inhibition of topoisomerase II (Topo II). Furthermore, as a Topo II inhibitor, compound 1 was found to effectively induced G2-M phase cell cycle arrest and apoptosis in cancer cells. [ABSTRACT FROM AUTHOR]

We investigated the loss of somatic mutations in TP53 and PIK3CA in breast cancer tissue after neoadjuvant chemotherapy (NCT) and the clinical relevance of the observed mutation profiles. Samples were derived from three cohorts: Cohort 1 consisting of 206 patients undergoing NCT with matched pre- and postchemotherapy tumor tissues; Cohort 2 consisting of 158 additional patients undergoing NCT; and Cohort 3, consisting of 81 patients undergoing chemotherapy with prechemotherapy tumor tissues. In the first cohort, somatic mutations in TP53 or PIK3CA were identified in 24.8% of the pre-NCT tumor samples but in only 12.1% of the post-NCT tumor samples (P < 0.001). Patients with initial TP53 and PIK3CA mutations who became negative for the mutations after NCT had a higher Miller-Payne score (P = 0.008), improved disease-free survival, and improved overall survival than those with no change or the opposite change. The association of loss of mutations in TP53 and PIK3CA and improved survival was successfully validated in the second cohort. In addition, 28.4% of the tumors showed intratumoral heterogeneity of somatic mutations in TP53 or PIK3CA, whereas 71.6% were homogeneous, either with or without the mutations. Our data reveal the novel concept that chemotherapy may reduce mutation frequency in patients with breast cancer. Furthermore, the loss of somatic mutations in TP53 and PIK3CA may be translated to biomarkers for prognosis via further verification, which may optimize the choice of sequential therapy and improve patient survival. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase 5 (Cdk5) is known to regulate prostate cancer metastasis. Our previous results indicated that Cdk5 activates androgen receptor (AR) and supports prostate cancer growth. We also found that STAT3 is a target of Cdk5 in promoting thyroid cancer cell growth, whereas STAT3 may play a role as a regulator to AR activation under cytokine control. In this study, we investigated the regulation of Cdk5 and its activator p35 on STAT3/AR signaling in prostate cancer cells. Our results show that Cdk5 biochemically interacts with STAT3 and that this interaction depends on Cdk5 activation in prostate cancer cells. The phosphorylation of STAT3 at Ser727 (p-Ser727-STAT3) is regulated by Cdk5 in cells and xenograft tumors. The mutant of STAT3 S727A reduces its interaction with Cdk5. We further show that the nuclear distribution of p-Ser727- STAT3 and the expression of STAT3-regulated genes (junB, c-fos, c-myc, and survivin) are regulated by Cdk5 activation. STAT3 mutant does not further decrease cell proliferation upon Cdk5 inhibition, which implies that the role of STAT3 regulated by Cdk5 correlates to cell proliferation control. Interestingly, Cdk5 may regulate the interaction between STAT3 and AR through phosphorylation of Ser727- STAT3 and therefore upregulate AR protein stability and transactivation. Correspondingly, clinical evidence shows that the level of p-Ser727-STAT3 is significantly correlated with Gleason score and the levels of upstream regulators (Cdk5 and p35) as well as downstream protein (AR). In conclusion, this study demonstrates that Cdk5 regulates STAT3 activation through Ser727 phosphorylation and further promotes AR activation by protein-protein interaction in prostate cancer cells. [ABSTRACT FROM AUTHOR]

This paper presents a modular self-controlled photovoltaic (PV) charger with maximum power point tracking (MPPT) and pulse-charging schemes. The studied PV modules can be flexibly parallel connected through interleaved operation using an interintegrated circuit (\I^2\C) interface. The MPPT control of PV panel is implemented by using a current-sensing technique with the on-state resistance Rds(on) of the power switch. Both an expensive hall-effect sensor and additional current-sensing resistor are not needed. A pulse-charging scheme without extra battery-current sensor is also designed to prolong the lifetime of the acid-lead battery. The operation principles and design considerations of the proposed PV charger are analyzed and discussed. A laboratory prototype is implemented and tested to verify its feasibility. [ABSTRACT FROM PUBLISHER]