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Estimations and applications of factor models often rely on the crucial condition that the number of latent factors is consistently estimated, which in turn also requires that factors be relatively strong, data are stationary and weakly serially dependent, and the sample size be fairly large, although in practical applications, one or several of these conditions may fail. In these cases, it is difficult to analyze the eigenvectors of the data matrix. To address this issue, we propose simple estimators of the latent factors using cross-sectional projections of the panel data, by weighted averages with predetermined weights. These weights are chosen to diversify away the idiosyncratic components, resulting in "diversified factors." Because the projections are conducted cross-sectionally, they are robust to serial conditions, easy to analyze and work even for finite length of time series. We formally prove that this procedure is robust to over-estimating the number of factors, and illustrate it in several applications, including post-selection inference, big data forecasts, large covariance estimation, and factor specification tests. We also recommend several choices for the diversified weights. for this article are available online. [ABSTRACT FROM AUTHOR]

The use of new psychoactive substances (NPSs) has markedly increased worldwide; thus, it is important to monitor NPS-related effects. The Taiwan Emergency Department Drug Abuse Surveillance (TEDAS) project aims to assess the patterns of recreational drug use in patients presenting to emergency departments (EDs) across the country. Here, we report the preliminary results of this project. This observational study included the collection and analysis of urine samples and assessment of the clinical presentation of patients from 79 EDs across Taiwan. Clinical features were recorded through a questionnaire filled by attending doctors or nurses who collected urine samples for clinical diagnosis. Urine samples were analyzed for 110 drugs and metabolites using electrospray ionization liquid chromatography-tandem mass spectrometry (LC-MS/MS). Between February and November 2019, a total of 2649 patients were enrolled for urine drug analysis. A total of 675 cases older than 12 years (males, n = 480) had NPS or other illicit drugs detected in their urine samples. Overall, 1271 counts of drugs, among which 717 (56.4%) were NPS. At least one NPS was detected in 340 patients (50.4%), and 292 cases were positive for multiple drugs. The most frequently detected drug was methamphetamine/amphetamine, followed by synthetic cathinones, ketamine and its two analogs, and opioids. The most common drug combination was cathinones plus ketamine and/or its analogs (n = 56). Younger patients (OR = 3.3, p≤.0001) and women (OR = 1.5, p =.01) were more likely to have NPS detected in their urine samples. NPS-positive cases frequently experienced chest pain (OR = 2.6, p =.03), tachycardia (OR = 2.6, p =.0002), and suicide attempt/non-suicidal self-harm (OR = 1.8, p =.004), whereas depressed consciousness (OR = 0.5, p =.001) was less frequent among NPS-positive cases than among other illicit drug-positive cases. The TEDAS project provides a nationwide epidemiological profile of recreational drug use in Taiwan. More than half of the recreational drugs were NPSs, which were comprehensively detected using LC-MS/MS. [ABSTRACT FROM AUTHOR]

Transmission lines are built to span over long distances, to which they are frequently exposed to many different situations that can cause abnormal conditions known as electrical faults. Electrical faults, when isolated, can cripple the transmission system as power flows are directed around these faults therefore leading to other numerous potential issues such as thermal and voltage violations, customer interruptions, or cascading events. Accurate fault classification and location is essential in reducing outage times and enhancing system reliability. Diverse methods exist and have different strengths and weaknesses. This paper aims to investigate the use of an intelligent technique based on artificial neural networks. The neural networks will attempt to determine the fault classification and precise fault location. Different fault cases are analyzed on multiple transmission line configurations using various phasor measurement arrangements from the two substations connecting the transmission line. The results can provide guidance on choosing the most efficient neural network structure and input measurements for transmission line fault classification and location. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mitogenome) of Miroplana shenzhensis Yu & Wang, 2013 is reported in the present study, representing the second mitogenome recorded in the suborder Maricola. The circular mitogenome is 14,344 bp in length, containing 12 protein-coding genes, 2 ribosomal RNAs and 22 transfer RNAs. Comparative analysis on mitochondrial gene order reveals a rearrangement in the suborder Maricola, indicating that mitochondrial gene order is conserved only in Continenticola, and is divergent across Tricladida. Phylogenetic analysis shows M. shenzhensis is clustered with an another marine triclad, forming a well-supported monophyletic group of Maricloan. [ABSTRACT FROM AUTHOR]

To date, many efforts have been made to explore how to support driver's decision-making process with advisory information. Previous studies mainly focus on a single modality, e.g. the visual, auditory or haptic modality. In contrast, this study compares data from two simulator studies with 50 participants in total, where the visual vs. the auditory modality was used to present the same type of advisory traffic information under the same driving scenarios. Hereby we compare the effect of these two modalities on drivers' responses and driving performance. Our findings indicate that modality influences the drivers' behaviour patterns significantly. Visual information helps drivers to drive more accurately and efficiently, whereas auditory information supports quicker responses. This suggests that there are potential benefits in applying both modalities in tandem, as they complement each other. Correspondingly, we present several design recommendations on Advisory Traffic Information Systems. [ABSTRACT FROM AUTHOR]

Transition-metal-substituted polyoxometalates have attracted attention due to their remarkable physicochemical properties and applications in many research areas. Two new multi-manganese-substituted silicotungstates, tetramer [{Mn3Cl(OH)3(SiO4)}4(SiW9O34)4]36- (1) and banana-shaped [((MnOH2)0.5Mn2SiW9O34)2(SiW6O26)]22- (2), were prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, etc. Compound 1 comprises four {SiW9O34} fragments, one {Mn3Cl(OH)3}4 cluster and four {SiO4} groups; it can form a 1 D-chain by connecting [{Mn3Cl(OH)3(SiO4)}4(SiW9O34)4]36− cluster units with Na+ cations. Banana-shaped 2 consists of two {(MnIIOH2)0.5MnIII2SiW9O34} fragments connected by a hexavacant {SiW6O26} motif, and it displays an interesting 3-D architecture by bridging banana-shaped [((MnIIOH2)0.5MnIII2SiW9O34)2(SiW6O26)]18- polyanion with four-member Na-cluster. 3-D packing of 2 along the c-axis creates two types of elliptical channels with sizes of 7.86 Å × 13.35 Å and 16.03 Å × 25.28 Å, respectively. Also, while coupling with [Ir(ppy)2(dtbbpy)]+ as photosensitizer and triethanolamine (TEOA) as sacrificial electron donor, both compounds show decent catalytic activity towards hydrogen production under visible LED light irradiation. [ABSTRACT FROM AUTHOR]

The traditional service restoration methods are experiencing a significant challenge because the performance of such methods is often dominated by very large processing time. Therefore, it is important to develop a fast and an accurate method to solve a complex non-linear optimization problem representing the service restoration problem in a distribution system. In this paper, due to a binary nature of the service restoration problem, the Binary Water Cycle Algorithm (BWCA) is proposed to reduce out-of-service loads and system losses considering operational constraints, the radial topology of the distribution systems, and the influence of the presence of distributed generations (DGs) on the service restoration problem. The proposed method is a modified form of the Water Cycle Algorithm (WCA) that is mainly used for discrete and continuous optimization problems. The effectiveness of the proposed method is validated by comparing with other well-known meta-heuristic algorithms using a modified IEEE 33-node radial distribution system. The simulation results demonstrate the robustness of this method to provide a precise decision with short convergence time for solving service restoration problems. [ABSTRACT FROM AUTHOR]

In this paper, we study employability in the group of talented employees. We explore how employees' temporal focus affects their dispositional employability and how dispositional employability influences their perceived internal career prospects. We also examine the moderating role of training perceived as developmental on the relationship between dispositional employability and perceived internal career prospects. Upon examination of these relationships within an organization that has a closed talent management approach, we find support for the hypothesized mediating and moderating relationships. Present and future focus were positively related to talents' dispositional employability, which in turn increased their perception of career prospects in the current company. The latter relationship was stronger among talents who perceived that they had received training for more important positions than those who did not. The results advanced current knowledge of antecedents and outcomes of employability in the specific group of talents and shed light on the organizational practices that may help with talent retention. [ABSTRACT FROM AUTHOR]

Distributed generation sources (DGs) are widely considered as important sources of power generation in distribution systems during the last few decades. Despite the substantial benefits of DGs, increasing the penetration level of the DGs can cause dramatic voltage magnitude fluctuations. Coordination of the use of dynamic reactive power sources such as photovoltaic (PV) inverters and voltage control equipment can mitigate rapid voltage magnitude fluctuations. A coordinated volt-var control method is proposed herein to achieve the optimal expected performance (e.g., system losses) while considering the spatial correlation among PV source powers and constraining the variability of voltage magnitudes throughout the distribution network within permissible ranges. The proposed strategy formulates chance constraints on the voltage magnitude and considers the uncertainty of PV power injections over the interval of interest to maintain voltage magnitudes within acceptable limits. The proposed method has been tested on the IEEE 123-node radial distribution system for validation. Moreover, the simulation results demonstrate that the proposed method can effectively mitigate the fast voltage magnitude deviations with an acceptable reduction in system losses in the presence of intermittent renewable resources. [ABSTRACT FROM AUTHOR]

5/6 Nephrectomy (PNx) on rat and mouse mimics renal failure after loss of kidney function in human, and it has been widely used in CKD researches. However, existing methods for PNx model construction present high mortality of animals after modeling due to hemorrhage and infection in or after surgery. Here, we report a novel and highly efficient PNx modeling method to simulate conventional 5/6 nephrectomy, which significantly reduced the mortality of animals and simplified the modeling procedures. In this novel modeling method, we directly ligated the upper and lower poles of left kidney after removal the right kidney 1 week later (l-PNx), which leads to necrosis of ligated upper and lower poles of the kidney and mimics the conventional 5/6 nephrectomy (c-PNx). After modeling 4 and 12 weeks, the serum creatinine, BUN and proteinuria levels were strongly increased in both c-PNx and l-PNx model. Importantly, compared with the c-PNx, l-PNx model present more severe renal fibrosis estimated by Masson staining, IHC and western blotting. The results showed that the protein levels of α-SMA were significantly increased in the kidney of c-PNx and l-PNx models, but more increase was found in l-PNx model. It is noteworthy that, compared with c-PNx model, the survival rate of l-PNx model was markedly increased. In summary, we established a novel and efficient 5/6 nephrectomy model, which can mimic conventional 5/6 nephrectomy to construct a renal fibrosis and renal failure mouse model, that is conducive to mechanism and treatment researches of CKD. [ABSTRACT FROM AUTHOR]

In this article, we consider a high-dimensional quantile regression model where the sparsity structure may differ between two sub-populations. We develop ℓ1-penalized estimators of both regression coefficients and the threshold parameter. Our penalized estimators not only select covariates but also discriminate between a model with homogenous sparsity and a model with a change point. As a result, it is not necessary to know or pretest whether the change point is present, or where it occurs. Our estimator of the change point achieves an oracle property in the sense that its asymptotic distribution is the same as if the unknown active sets of regression coefficients were known. Importantly, we establish this oracle property without a perfect covariate selection, thereby avoiding the need for the minimum level condition on the signals of active covariates. Dealing with high-dimensional quantile regression with an unknown change point calls for a new proof technique since the quantile loss function is nonsmooth and furthermore the corresponding objective function is nonconvex with respect to the change point. The technique developed in this article is applicable to a general M-estimation framework with a change point, which may be of independent interest. The proposed methods are then illustrated via Monte Carlo experiments and an application to tipping in the dynamics of racial segregation. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

There has not been a satisfactory solution to identifying and locating evolving faults on transmission lines until now. This paper presents an integrated detection and location approach for evolving faults based on transient traveling waves. Evolving faults include two sequential faults, resulting in the change of fault phase. The feature aerial mode of captured current traveling wave only reflects the feature of the second fault occurrence, and is used for analyzing the second fault. By combining traveling wave and transient energy features, fault phase selection can be implemented at two stages: the initial fault occurrence, and the short period before fault clearance. The evolving faults can be determined according to the consistency of the two-stage phase-selection results. Subsequently, the positions of the two successive faults can be precisely acquired by individually implementing the double-ended traveling wave fault location on the initial fault phase as well as the feature aerial mode currents, respectively. Digital simulation studies based on the simulation software PSCAD/EMTDC demonstrate that the proposed method is feasible and effective. [ABSTRACT FROM PUBLISHER]

–To enhance the accuracy and reliability of fault-location estimates, an optimal fault-location estimator for power distribution systems with distributed generations is proposed in this article. Voltage and current measurements recorded at certain location/locations, such as power generation sites, are employed to estimate the fault location. The proposed method is able to make the most of available measurements, which may be from one location or multiple locations. Based on optimal estimation theory, the method is able to estimate the fault location, fault resistances, and true value of measurements. A chi-squared test is adopted to detect and identify possible bad measurements for improved estimation results. Evaluation studies based on a sample power distribution system have been carried out. Evaluation studies have demonstrated that the proposed method is effective for obtaining accurate fault-location estimates, as well as detecting and identifying possible bad measurements. [ABSTRACT FROM PUBLISHER]

Power distribution systems are desired to operate at their optimal control settings. These settings typically mean operation at low energy consumption and minimized distribution losses. Renewable energy resources can be very important for efficient operation of the distribution systems. However, when the number of renewables in the distribution system increases, the complexity of the control also increases. Intermittent renewable resources, particularly wind and solar, can cause significant fluctuations in distribution feeder voltages. This article presents a dual-layer control approach for finding the optimal feeder control settings and maintaining the feeder voltages within specified limits between the optimization intervals. The load-tap changer transformers, voltage regulator, capacitor banks, and smart inverters participate in the global control, while the smart inverters deal with the fast changing transients at the local control level. Thus, this control scheme will take full advantage of power-electronics-based smart inverters to reduce or eliminate fast transients, and also reduce the wear and tear of mechanical controllers. Evaluation studies are performed based on the IEEE 37 node radial test feeder under varying load and generation conditions. The results demonstrate that the proposed approach is promising for voltage and VAR control of distribution feeders with intermittent resources. [ABSTRACT FROM AUTHOR]

Most of the fault-location methods developed in the past employed measurements obtained from a limited number of meters installed in a power system. Optimal meter placement in power systems is to make the best use of a limited number of meters available to keep the entire network observable. This article presents the fault-location observability analysis for distribution systems and proposes a novel optimal meter placement algorithm to keep the system observable in terms of fault-location determination. First, the observability of fault location in power systems is defined. Then analysis of the whole system is performed to determine the fewest number of meters needed and the best locations to place those meters to achieve fault-location observability. Case studies based on a 16-bus distribution system have been carried out to illustrate the proposed algorithms. [ABSTRACT FROM AUTHOR]

We developed and psychometrically tested four scales for measuring the perceptions of parental smokers and family members’ influences on smoking behavior in the presence of children in Taiwan. Data were collected from 309 parental smokers with school-aged children. The results of factor analysis revealed two to three factors within each scale, and the reliability was between 0.63 and 0.91, based on Cronbach’s alpha. Our findings provide preliminary support for the reliability and validity of the scales. The collective application of the scales is comprehensive that may constitute a feasible approach for preventing parental smoking. [ABSTRACT FROM PUBLISHER]