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Seasonal climate forecasts have socioeconomic value, and the quality of the forecasts is important to various societal applications. Here we evaluate seasonal forecasts of three climate variables, vapor pressure deficit (VPD), temperature, and precipitation, from operational dynamical models over the major cropland areas of South America; analyze their predictability from global and local circulation patterns, such as El Niño–Southern Oscillation (ENSO); and attribute the source of prediction errors. We show that the European Centre for Medium-Range Weather Forecasts (ECMWF) model has the highest quality among the models evaluated. Forecasts of VPD and temperature have better agreement with observations (average Pearson correlation of 0.65 and 0.70, respectively, among all months for 1-month-lead predictions from the ECMWF) than those of precipitation (0.40). Forecasts degrade with increasing lead times, and the degradation is due to the following reasons: 1) the failure of capturing local circulation patterns and capturing the linkages between the patterns and local climate; and 2) the overestimation of ENSO’s influence on regions not affected by ENSO. For regions affected by ENSO, forecasts of the three climate variables as well as their extremes are well predicted up to 6 months ahead, providing valuable lead time for risk preparedness and management. The results provide useful information for further development of dynamical models and for those who use seasonal climate forecasts for planning and management. SIGNIFICANCE STATEMENT: Seasonal climate forecasts have socioeconomic value, and the quality of the forecasts is important to their applications. This study evaluated the quality of monthly forecasts of three important climate variables that are critical to agricultural management, risk assessment, and natural hazards warning. The findings provide useful information for those who use seasonal climate forecasts for planning and management. This study also analyzed the predictability of the climate variables and the attribution of prediction errors and thus provides insights for understanding models’ varying performance and for future improvement of seasonal climate forecasts from dynamical models. [ABSTRACT FROM AUTHOR]

Context: Zuojin Pill (ZJP) has been used to treat gastrointestinal problems in China for hundreds of years. Objective: To discover more potential active ingredients and evaluate the gastroprotective mechanisms of ZJP. Materials and methods: An approach involving UPLC-Q-Orbitrap HRMS and serum pharmacochemistry was established to screen the multiple chemical constituents of ZJP. Male Sprague-Dawley (SD) rats were divided into six groups: normal control, ulcer control, omeprazole (30mg/kg), and three ZJP groups (1.0, 2.0 and 4.0 g/kg). After oral treatment with ZJP or omeprazole for 7 days, all groups except the normal control group were orally administered 5 mL/kg ethanol to induce gastric ulceration. Histopathological assessment of gastric tissue was performed by haematoxylin and eosin staining. Antioxidant parameters and inflammatory mediators were determined using ELISA Kit and immunohistochemical analysis. Results: Ninety components were identified in ZJP. Among them, 23 prototypes were found in rat serum after oral administration of ZJP. The ulcer inhibition was over 90.0% for all the ZJP groups. Compared with the ulcer control rats, ZJP (4.0 g/kg) enhanced the antioxidant capacity of gastric tissue: superoxide dismutase (1.33-fold), catalase (2.61-fold), glutathione (2.14-fold), and reduced the malondialdehyde level (0.48-fold). Simultaneously, the ZJP meaningfully lowered the content of tumour necrosis factor-a (0.76-fold), interleukin-6 (0.66-fold), myeloperoxidase (0.21-fold), and nuclear factor kappa B (p65) (0.62-fold). Discussion and conclusions: This study showed ZJP could mitigate ethanol-induced rat gastric ulcers, which might benefit from the synergistic actions of multiple ingredients. The findings could support the quality control and clinical trials of ZJP. [ABSTRACT FROM AUTHOR]

A common issue with morphing structures is that the actuators must work against significant structural and aerodynamic stiffness. The concept of passive energy balancing (PEB) aims to ameliorate this, and thereby reduces system mass, by connecting negative stiffness elements to the actuated degrees of freedom. However, these devices can be complex to design and will also add their own mass to the system. It is therefore difficult to determine the potential for system-level mass saving without significant detailed design effort. This work treats a PEB device as essentially a local energy storage mechanism. This framework leads to an approach to optimization that will deliver a lightweight PEB mechanism in addition to reducing actuator requirements. It also allows a high-level method to obtain an approximate evaluation of system-level benefits with only basic information about the application being considered, by comparing general properties of the actuators used to the energy storage properties of the underlying materials used in the PEB device. The work concludes with a case study that shows how the PEB can potentially reduce system mass both through reduced energy consumption requirements and actuator mass savings, and can work particularly well for actuators with nonideal stroke/force profiles. [ABSTRACT FROM AUTHOR]

Witnessing intimate partner violence (IPV) is associated with adolescents' externalizing behavior problems such as bullying and aggression, but its association with cyberbullying perpetration remains unclear. Given the prevalence of cyberbullying perpetration, this study aims to examine the relationship between witnessing IPV and cyberbullying perpetration, and also to explore whether self-control mediates, and parental psychological control (PPC) moderates the association. 1,670 primary and junior high school students (aged from 10 to 15 years, 53.7% boys) in China participated in the questionnaire survey in May, 2017. The results showed that witnessing IPV positively predicted cyberbullying perpetration significantly when sex and grade were controlled. Self-control partially mediated the relationship between witnessing IPV and cyberbullying perpetration, while PPC moderated the relation between witnessing IPV and cyberbullying perpetration. Specifically, the effect of IPV on cyberbullying perpetration was stronger when PPC was high compared to when PPC was low. Multigroup analysis showed that the effect of witnessing IPV on cyberbullying perpetration was stronger in boys than in girls and the mediation effect of self-control was stronger among junior high school students than among primary schools. The implications for intervention of cyberbullying perpetration are discussed. [ABSTRACT FROM AUTHOR]

A flower-like nickel-cobalt-manganese hydroxide (NiCoMn-OH) modified with two-dimensional Ti3C2 nanoflakes has been synthesized via simple one-step hydrothermal method. The NiCoMn-OH/Ti3C2 composite exhibits a high specific capacity of 670.3 C/g at a specific current of 1 A/g, higher than 614.6 C/g for NiCoMn-OHand 8.9 C/g for Ti3C2 at the same conditions. The improved electrochemical performance is due to that Ti3C2 is absorbed and distributed on the surface of NiCoMn-OHin its situ synthesis process and enhances its electro-activity. The hybrid supercapacitor based on NiCoMn-OH/Ti3C2 and RGO shows high specific capacity of 177.5 C/g at 0.5 A/g and 103.1 C/g at 10 A/g, retaining 93.28% of initial capacity after 5000 charge/discharge cycles at 7 A/g. The hybrid supercapacitor also displays extraordinary specific energy of 41.15 Wh/kg at a specific power of 375 W/kg and 21.46 Wh/kg even at 7.5 kW/kg. [ABSTRACT FROM AUTHOR]

The Y chromosome of Drosophila melanogaster is pivotal for male fertility. Yet, only 16 protein-coding genes reside on this chromosome. The Y chromosome is comprised primarily of heterochromatic sequences, including DNA repeats and satellite DNA, and most of the Y chromosome is still missing from the genome sequence. Furthermore, the functions of the majority of genes on the Y chromosome remain elusive. Through multiple genetic strategies, six distinct segments on the Y chromosome have been identified as “male fertility factors,” and candidate gene sequences corresponding to each of these loci have been ascribed. In one case, kl-3, a specific protein coding sequence for a fertility factor has been confirmed molecularly. Here, we employed CRISPR/Cas9 to generate mutations, and RNAi, to interrogate the requirements of protein coding sequences on the Y chromosome for male fertility. We show that CRISPR/Cas9-mediated editing of kl-2 and kl-5 causes male sterility, supporting the model that these gene sequences correspond to the cognate fertility factors. We show that another gene, CCY, also functions in male fertility and may be the ks-2 fertility factor. We demonstrate that editing of kl-2, kl-3, and kl-5, and RNAi knockdown of CCY, disrupts nuclear elongation, and leads to defects in sperm individualization, including impairments in the individualization complex (IC) and synchronization. However, CRISPR/Cas9 mediated knockout of some genes on the Y chromosome, such as FDY, Ppr-Y, and Pp1-Y2 do not cause sterility, indicating that not all Y chromosome genes are essential for male fertility. [ABSTRACT FROM AUTHOR]

A series of Ni–Fe/MCM-41 bimetallic catalysts and also Ni/MCM-41 and Fe/MCM-41 catalysts were prepared by the incipient-wetness impregnation method and tested for their activity for CO methanation in a continuous-flow microreactor. The results showed that the catalytic activities of the Ni–Fe/MCM-41 bimetallic catalysts were much higher than those of the Ni/MCM-41 and Fe/MCM-41 catalysts at low temperatures (200°C–325°C). The 10%Ni–5%Fe/MCM-41 catalyst showed the best activity with a CO conversion of almost 100% and a CH4 selectivity of 98% at 350°C under a pressure of 1.5 MPa with a 3:1 molar ratio of H2 to CO and a weight hourly space velocity of 12,000 mL h−1 g−1. The catalysts were characterized by N2 physisorption measurements, X-ray diffraction, and H2-temperature-programmed reduction. The results showed that the addition of Fe will lead to the formation of finer Ni particles and Ni–Fe alloy, which were the main reasons for the activity increase in the Ni–Fe/MCM-41 catalysts. [ABSTRACT FROM AUTHOR]

Aiming to verify the concept of using heteroclinic connections to reconfigure smart structures, a multistable buckled beam with integrated Shape Memory Alloy (SMA) wires is utilized as a high fidelity model. The Shape Memory Alloy (SMA) wires are resistively heated to provide the actuation force to stabilize the unstable configuration and the transition of the beam from one unstable equilibrium condition to the other. This concept provides a means of reducing the energy requirement for transitions between configurations of the structure, which is an energy-efficient reconfiguration scheme between equal-energy unstable (but actively controlled) equilibria. This letter presents a detailed design of the system, and how the active (heated) SMA wires control the structure stay in unstable configuration and drive the structure to achieve reconfiguration. Exploiting the instability of the smart structure has significant interests in many power reduction applications, including active flow control, reconfiguration of large deployable aerospace structures, and MEMS devices. [ABSTRACT FROM AUTHOR]

A reconfigurable smart surface with multiple equilibria is presented, modelled using discrete point masses and linear springs with geometric nonlinearity. An energy-efficient reconfiguration scheme is then investigated to connect equal-energy unstable (but actively controlled) equilibria. In principle, zero net energy input is required to transition the surface between these unstable states, compared to transitions between stable equilibria across a potential barrier. These transitions between equal-energy unstable states, therefore, form heteroclinic connections in the phase space of the problem. Moreover, the smart surface model developed can be considered as a unit module for a range of applications, including modules which can aggregate together to form larger distributed smart surface systems. [ABSTRACT FROM AUTHOR]

An improved understanding of both community attitudes toward tourism and host–guest interaction is vital for the sustainable development of tourism. However, there are significant research deficiencies and gaps in these two related research areas. This conceptual paper looks into these glaring research gaps through a review of literature and attempts to provide solutions suggested by an ongoing research project being conducted in Melbourne, Victoria, Australia. In particular, while this paper addresses the impacts of personality and ethnicity on community attitudes toward tourism and points to the urgent need for a well-established theoretical framework in order to understand and predict host–guest interaction, it also highlights the above issues in the context of the urban–rural fringe, the bordering region connecting neat ‘urban’ and ‘rural’ areas. [ABSTRACT FROM AUTHOR]

Although cantilevered variable nozzle vane (VNV) is already used in engineering practice, few researches about cantilevered variable geometry turbine (VGT) aerodynamic performance can be found in public references. In order to find the difference between conventional and cantilevered VGT performances and provide references for VNV design practice, the aerodynamic performances of three single‐stage VGTs with different VNVs were compared by the three‐dimensional numerical simulation method. The VNVs of VGTs here included conventional, cantilevered, and no clearance VNVs. All three VGTs had spherical endwalls in the nozzle. The influences of nozzle spherical endwalls, vane end clearances, and vane rotation angles on VGT performances were investigated. The computation results show that the nozzle spherical endwalls enhance the radial mass flow immigration in the nozzle front part and increase the turbine mass flow rate by 0.79%. Some nozzle vane end clearance leakage flows near the vane trailing edge with higher axial speed can improve the mass flow rate further. Compared with the no clearance VGT, the conventional VGT efficiency is lower by 0.0082, and the cantilevered VGT efficiency is lower by 0.0293. When the VNV rotation angle increases by 1°, the VGT mass flow rate decreases by approximately 0.36 kg/s, and the expansion ratio improves by around 0.05. The cantilevered VGT had enormous VNV hub leakage loss, and its efficiency was lower than the conventional VGT by at least 0.01 within the range of VNV rotation angles. The cantilevered VNV hub creates more loss when VGT works at lower expansion ratio conditions. [ABSTRACT FROM AUTHOR]

A simulation environment is presented that predicts the flight trajectory of a maneuvering multirotor aircraft using a purely physics‐based approach without the need for a priori flight test data. The flight dynamics model determines the motion of the aircraft based on the total loads and commanded motor speeds. The aerodynamic loads of the rotors are predicted using a modified blade element momentum theory (BEMT)–based approach that considers nonuniform inflow conditions at the rotor discs. In addition, the aerodynamic loads of the remaining aircraft components are estimated using a load decomposition. Flight test data of an AscTec Pelican quadcopter were used to evaluate the prediction quality by comparing it with the vehicle tracks recorded in flight tests. As the flight changes from hover, the present approach shows significant prediction improvements over a simple KΩ2 approach. Specifically, when comparing the number of successful prediction timesteps into the future, the BEMT‐based approach showed, on average, 44.4% longer successful predicting for positional velocities and 85.3% longer for predicting body rates. In addition to its numerical accuracy, the simulation environment is computationally efficient and thus ideal for design studies of flight controllers. The codes associated with the simulation environment are open source. [ABSTRACT FROM AUTHOR]

Although the field of Human Resource Management has been extensively studied in the previous decades, still remaining theoretical and methodological questions are yet to be answered. These questions were found to evolve around how to conceptualize and operationalize HRM as well as the mechanism through which HRM affects performance. Consequently, numerous models were proposed to address these questions and among which the AMO model is considered the one that grasp the attention of many scholars. The current study, therefore, aims to address these questions by investigating the mediating effect of employees’ Ability (A), Motivation (M), and Opportunity to participate (O) model on the relationship between HRM system and employees’ affective commitment. An abstract level of HRM system was operationalized and hypothesized to have an indirect effect on employees’ affective commitment via the AMO model. A cross-sectional data was gathered through a questionnaire survey distributed to 800 employees working in the telecommunications sector in Kuwait. Structural equation modelling (SEM) via AMOS22 was used to build and test the hypothesized model. The confirmatory factor analysis (CFA) has revealed that the abstract level HRM system is better conceptualized as having three categories namely, Skill enhancing HRM practices, Motivation enhancing HRM practices, and Empowerment enhancing HRM practices. Moreover, the results have indicated that HRM system significantly and positively affect employees’ ability, motivation, and opportunity to participate. More importantly, the results have supported that the relationship between HRM system and employees’ affective commitment is partially mediated by the AMO model. This study has contributed to the field of Human Resource Management by empirically justifying the critical role that employees’ ability, motivation, and opportunity to participate (AMO) have in increasing employees’ affective commitment. Accordingly, the current study is directing the attention of the telecommunications companies’ managers toward designing their HRM system in ways that increase the three dimensions of the AMO model, which inn turn could result in increased level of commitment. [ABSTRACT FROM AUTHOR]

Although the field of Human Resource Management has been extensively studied in the previous decades, still remaining theoretical and methodological questions are yet to be answered. These questions were found to evolve around how to conceptualize and operationalize HRM as well as the mechanism through which HRM affects performance. Consequently, numerous models were proposed to address these questions and among which the AMO model is considered the one that grasp the attention of many scholars. The current study, therefore, aims to address these questions by investigating the mediating effect of employees' Ability (A), Motivation (M), and Opportunity to participate (O) model on the relationship between HRM system and employees' affective commitment. An abstract level of HRM system was operationalized and hypothesized to have an indirect effect on employees' affective commitment via the AMO model. A cross-sectional data was gathered through a questionnaire survey distributed to 800 employees working in the telecommunications sector in Kuwait. Structural equation modelling (SEM) via AMOS22 was used to build and test the hypothesized model. The confirmatory factor analysis (CFA) has revealed that the abstract level HRM system is better conceptualized as having three categories namely, Skill enhancing HRM practices, Motivation enhancing HRM practices, and Empowerment enhancing HRM practices. Moreover, the results have indicated that HRM system significantly and positively affect employees' ability, motivation, and opportunity to participate. More importantly, the results have supported that the relationship between HRM system and employees' affective commitment is partially mediated by the AMO model. This study has contributed to the field of Human Resource Management by empirically justifying the critical role that employees' ability, motivation, and opportunity to participate (AMO) have in increasing employees' affective commitment. Accordingly, the current study is directing the attention of the telecommunications companies' managers toward designing their HRM system in ways that increase the three dimensions of the AMO model, which inn turn could result in increased level of commitment. [ABSTRACT FROM AUTHOR]

Despite the promising relationship that has been reported between HRM and Organization Performance (OP) in the last two decades, it is found that good HRM system and practices do not directly lead to better organization performance. However, questions remain about what factors mediate the HRM-OP relationship, which is commonly referred to as the "black box". The aim of this paper, therefore, is to develop and propose a conceptual model that captures the mediating effects of organizational factors such as "AMO" (skills and Abilities, Motivation, and Opportunity to participate), employees' attitudes, and employees' behaviors on the relationship between the HRM system and organizational performance. The proposed model intends to integrate both the content and the process approach to HRM. The paper, as a part of a project, uses an operationalization method to develop a theory-based model. The model development process involves a large amount of review of the literature in the field of HRM and OP. Analysis of the key concepts is conducted. The potential association and relationship among the factors are identified through integration of the findings in the mainstream literature. In the second stage of the project, the proposed model will be empirically tested by quantitative method. A questionnaire survey will be carried out to collect primary data using random sampling method. Structural Equation Modelling (SEM) technique will be utilized for data analysis. Validity and reliability tests will be performed. Drawing on literature review, this paper supports the assertion that the impact of HRM on OP is indirect. Such impacts are achieved through its impacts on employees. Based on the operationalization, a conceptual framework is presented to represent the mediating effects of the factors on the relationship between the HRM system and organizational performance. The proposed framework argues that employees' AMO, attitudes and behavior should be sequentially considered as the mediating factors in the HRM-OP relationship. Moreover, shared perceptions among employees (strong climate) towards the HRM system should have a significant moderating effect on the HRM-AMO relationship. It is expected that the findings from this paper and project can partially unlock the "black box" in the HRM-OP relationship. The proposed framework can help organizations realize that good HRM policy does not directly lead to expected OP. Policies and systems should be in place to monitor whether and how HRM system help achieve OP through its influences on employees. [ABSTRACT FROM AUTHOR]

A near-field planar array of wideband dual polarized antennas for plane-wave synthesis has been investigated. The paper presents a PWG with a concentric ring array of 84 Vivaldi antennas which can work at 0.6GHz-3GHz. The constraint least square (CLS) algorithm is used to optimize the weight coefficients of the array elements, which effectively reduce the influence of system uncertainty on quiet zone (QZ) ripple. To reduce the system cost and complexity, the array elements in each concentric ring form a sub-array and the elements of the same sub-array adopt a passive beam forming network. The simulation and initial test results of a circular QZ with a diameter of 600 mm are given. The results demonstrate the feasibility of our design. [ABSTRACT FROM AUTHOR]

Objectives: In this study, we conducted a longitudinal evaluation of changes in medication adherence and the role of psychosocial and interpersonal factors in these changes among Blacks with type 2 diabetes mellitus (T2DM), and determined barriers and facilitators of T2DM medication adherence. Methods: We used an explanatory sequential mixed methods design for a sample of 287 black adult patients with T2DM in Wisconsin. Two surveys quantitatively evaluated changes in medication adherence, psychosocial factors, and interpersonal factors over time. We conducted 10 semi-structured qualitative interviews to explore participants' perceptions of these changes. Data integration of the quantitative and qualitative findings elucidated barriers and facilitators of medication adherence. Results: Increased adherence was significantly correlated with less concerns about medicines (r = -0.31), higher self-efficacy (r = 0.47), lesser depressive symptoms (r = -0.26), and lesser negative illness perceptions (r = -0.26) at both baseline and follow-up. Patient perceptions of adherence changes included adherence motivators, social support, and complex medication regimens. Integration showed that barriers and facilitators both existed in individuals who had an increase or a decrease in adherence over time. Conclusions: Specific beliefs of Blacks towards T2DM medications must be addressed to improve their adherence. Interventions must be tailored using interpersonal factors. [ABSTRACT FROM AUTHOR]

Background: Neuropsychiatric symptoms in Huntington's disease (HD) are often evident prior to clinical diagnosis. Apathy is highly correlated with disease progression, while depression and irritability occur at different stages of the disease, both before and after clinical onset. Little is understood about the neural bases of these neuropsychiatric symptoms and to what extent those neural bases are analogous to neuropsychiatric disorders in the general population. Objective: We used Diffusion Tensor Imaging (DTI) to investigate structural connectivity between brain regions and any putative microstructural changes associated with depression, apathy and irritability in HD. Methods: DTI data were collected from 39 premanifest and 45 early-HD participants in the Track-HD study and analysed using whole-brain Tract-Based Spatial Statistics. We used regression analyses to identify white matter tracts whose structural integrity (as measured by fractional anisotropy, FA) was correlated with HADS-depression, PBA-apathy or PBA-irritability scores in gene-carriers and related to cumulative probability to onset (CPO). Results: For those with the highest CPO, we found significant correlations between depression scores and reduced FA in the splenium of the corpus callosum. In contrast, those with lowest CPO demonstrated significant correlations between irritability scores and widespread FA reductions. There was no significant relationship between apathy and FA throughout the whole brain. Conclusions: We demonstrate that white matter changes associated with both depression and irritability in HD occur at different stages of disease progression concomitant with their clinical presentation. [ABSTRACT FROM AUTHOR]

FTY720 is a promising drug in attenuating multiple sclerosis, prolonging survival of organ allograft, and many other protective effects. Its mechanism of action is considered to be mediated by the internalization of sphingosine 1-phosphate receptors (S1PRs). In the current study, we investigated the efficacy of FTY720 in Non-Obese Diabetic (NOD) mice, serving as a model of Dry Eye Disease (DED). NOD mice were divided into six study groups, i.e., FTY720-treated groups with 3 concentrations of FTY720 (0.05%, 0.005%, and 0.001%), 0.05% Cyclosporin A (CsA) treated group, normal saline treated group, and no treatment control group. FTY720 was reconstituted with normal saline and prepared as eye drop. The stability and production of tear film was measured by Tear Break up Time test (TBUT) and phenol red cotton thread test (PRCTT), respectively. Tear fluid washings were collected and assessed by ELISA. Cytokines were detected in lacrimal glands by RT-PCR. Inflammation in conjunctiva was assessed by immunohistochemistry, goblet cells and conjunctival epithelia were examined and evaluated by impression cytology. Our results indicated that FTY720 had a significantly therapeutic effect in NOD mice. After FTY720 intervention, TBUT and PRCTT data were greatly improved (p < 0.01), the interleukin 1ß (IL-1ß) level was markedly decreased in tear fluid washings compared to control and normal saline groups after 2 weeks (Control: 1.06 ± 0.12, Normal saline:0.97 ± 0.09 pg/ml, CsA:0.22 ± 0.02 pg/ml, 0.001% FTY720:0.23 ± 0.02 pg/ml, 0.005% FTY720:0.14 ± 0.03 pg/ml, 0.05% FTY720: 0.18 ± 0.03 pg/ml. CsA group and 3 FTY720 groups VS. control group and normal saline groups: p < 0.01). Proinflammatory factors were greatly decreased in lacrimal glands (p < 0.01). Leukocytes were identified and markedly decreased in conujnctiva (p < 0.01), inflammatory reaction of DED was greatly relieved. More importantly, the goblet cells were largely restored and ocular surface lesions were significantly ameliorated (p < 0.01). Thus, we observed FTY720 alleviated DED in NOD mice by inhibiting leukocytes, the function of ocular surface tissue in NOD mice was partially restored via inhibiting ocular surface inflammation and increasing the density of goblet cells and conjunctival epithelia. FTY720 may offer a novel strategy for the treatment of inflammatory disorders in the ocular surface. [ABSTRACT FROM AUTHOR]

A 52-year-old man with a history of factor V Leiden thrombophilia, persistent headaches and papilloedema presented with worsening vision and confusion. MRI and MR angiography of the brain at the time of this presentation showed findings concerning for transverse sinus thrombosis and an associated dural arteriovenous fistula. Dural venous sinus thrombosis can lead to the formation of a dural arteriovenous fistula, which must be considered in the differential diagnosis for intracranial hypertension in patients with thrombophilia. [ABSTRACT FROM AUTHOR]