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Although the efficiency of Cu(In , Ga)Se 2 (CIGS) solar cells have exceeded 22% for the absorber with thickness more than 2 µm, thinning the absorber thickness has attracted attention to save the material costs of indium and gallium as well as to increase manufacturing throughput. However, a trade-off exists between efficiency and thickness of CIGS absorbers. In this work, we report a new insight to promote the efficiency of ultrathin (hundred-nanometer scale) CIGS solar cells by engineering Na-transport in a direct sputtering process with a quaternary CIGS target without post-selenization. We first demonstrate a feasibility to manipulate the preferred orientation of CIGS absorbers via controlled texture growth of the Mo underlayers. Then, we reveal that the amount of Na content within absorbers is strongly related to the preferred orientation and Cu-content of CIGS. The Cu-deficient CIGS absorbers grown on (211)-Mo underlayer show the strongest (220/204) CIGS texture and highest Na content, leading to enhanced efficiency. Through adequate Na-transport engineering and commonly used Ga gradient, we have significantly enhanced the efficiency of ultrathin (550 nm) CIGS solar cells to 10.04%. Our results unveil the key factors of Na-transport in nano-scale and provide a strategy to achieve high-efficiency ultrathin CIGS solar cells. [ABSTRACT FROM AUTHOR]

Microdeletion at 22q11.2, a common copy number variation (CNV) noted in neurodevelopmental disorders, may be associated with cognitive impairment. However, cognitive function in individuals with microduplication remains unclear. This work presents the genetic, clinical, and brain structural data of two men out of 335 probands with autistic spectrum disorder (ASD) who had different CNV dosages at 22q11.2, and comparison with their siblings, 55 ASD probands, and 73 controls. Both showed severe autistic symptoms, but the proband with microduplication demonstrated better cognitive functions. Furthermore, different cingulate gyrus volume changes were noted, indicating that the proband with 22q11.2 microduplication had a different pattern of cingulate gyrus structure. Our comprehensive characterization of the behavioral, cognitive, and imaging phenotypes of ASD probands with different CNV dosage at 22q11.2 contribute to how copy number changes at 22q11.2 mediate the phenotypes in ASD, and pave the way for future clinical and functional study on these variants. [ABSTRACT FROM AUTHOR]

Control of Se content during manufacturing process has been known to determine the efficiency of Cu(In x Ga 1− x )Se 2 (CIGS) solar cells. However, how Se is distributed in CIGS films and how Se distribution in hundred-nanometer scale affects the cell performance have not been realized due to limited spatial resolution of composition mapping technique. In this study, a promising nondestructive analysis by using field-emission electron probe microanalysis (FE-EPMA) is first demonstrated to directly probe the Se distribution within the depletion region of CIGS absorbers. We observe that Se-deficient-related defects are still exist in CIGS films even with high Se concentration but non-uniform distribution, leading to relatively low efficiency (~7%). By correlating photoluminescence spectra and conductivity mapping with composition distribution, we clarify that the uniform Se distribution is the key factor to suppress the defect formation and to enhance the p–n inversion at grain boundaries, resulting in significant efficiency boost to 12%. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies on vibration training have all been based on protocols at different combinations of frequencies and amplitudes without controlling the loading intensity. Objectives: This study investigated the effect of an 8-week vibration training program, under identical acceleration loads with various frequencies and amplitudes, on jumping performance, muscle activation and body balance. Design: Fifty young adults were randomly assigned to an high-frequency (32Hz, 1mm, and 4g), low-frequency (18Hz, 3mm, and 4g), or a control group. The high-frequency and low-frequency groups underwent 60s of squats exercise on the specific vibration platform three times a week, whereas the control group was trained without vibration. Methods: A force platform was used to measure the center of pressure of a static single leg stance, and the heights and impulse of two consecutive countermovement jumps before and after intervention. The activation of the rectus femoris and biceps femoris were also measured synchronously by surface electromyography. Results: The heights and impulse of both the first and second countermovement jumps were significantly increased and the area of center of pressure was significantly decreased after training in both the high-frequency and low-frequency groups (P <.05). Consequently, activation of the rectus femoris during the first countermovement jump was significantly lower than the pre-training value in the HF group but increased in the low-frequency group after training (P <.05). Conclusions: An 8-week identical acceleration vibration training regimen with various frequencies and amplitudes can significantly improve jumping performance and body balance, but the specific neuromuscular adaptation is possibly induced by different training settings. [Copyright &y& Elsevier]

Abstract: The characteristics of the Cu-rich Cu(In,Ga)Se2 (CIGS) films prepared by one-step sputtering process from a single quaternary target have been studied. The influences of working pressure, substrate temperature, Mo back contact, and KCN treatment on the properties of CIGS films were investigated. Target stability has been in-situ monitored by using optical emission spectroscopy. Obvious compositional change due to the KCN effect was observed, while only slight variation was caused by working pressure. We found the preferred orientation and crystallinity of one-step sputtered CIGS films were affected by the working pressure and substrate temperature when CIGS were directly deposited on the glass substrates. However, for the device fabrication, Mo back contacts dominated the growth behavior of CIGS films and induced better crystallinity with larger CIGS grain sizes. To explore the electrical properties of CIGS films on Mo back contacts, we developed a simple two-point probe measurement to examine the conductive channels within CIGS films before the device fabrication. Finally, one-step sputtered CIGS devices showed the efficiency of more than 8% at the working pressure of 0.4–2.7Pa with KCN treatment. [Copyright &y& Elsevier]

Abstract: One-step fabrication of the chalcopyrite Cu(In,Ga)Se2 (CIGS) absorber layer without excess Se supply during/after deposition or post-selenization treatments is reported. By using pulse DC sputtering from a single quaternary CIGS target, the chalcopyrite structure is spontaneously developed on the substrate at 500°C even without extra Se supply. The obtained CIGS absorber layer possesses columnar grains with (112) preferred orientation. Device efficiency of 8.22% is observed for slightly Se-deficient CIGS films. By further tuning the target composition, the efficiency is enhanced to 10.14%. We demonstrate that the device-quality CIGS absorber can be formed even in the Se-deficient environment and further improvement of efficiency can be achieved by tuning the Se content of the target. Accordingly, our one-step sputtering process shows great potential for mass production of thin film CIGS solar cells with a low cost and a high throughput. [Copyright &y& Elsevier]

Background: Methamphetamine abuse and addiction can lead to impaired cognition and psychosis, and there is no effective treatment for methamphetamine-induced mental illnesses. Objective: The aim of this study was to test whether repeated electroconvulsive shock (ECS) treatment has a therapeutic effect on methamphetamine-induced abnormal behavior in mice. Methods: To test the effects of ECS on methamphetamine-induced psychosis, ICR mice were randomly assigned to administration with either chronic methamphetamine or saline injection, and then both groups underwent post-treatment with either six once-daily ECS treatments or parallel sham controls. Prepulse inhibition (PPI), the novel object recognition test (NORT) and behavioral sensitization were performed for behavioral evaluation between the groups. To test the effects of ECS on methamphetamine addiction, methamphetamine-induced conditioned place preference (CPP) was examined after ECS and drug-primed reinstatement in the other set of experiments. Results: The animals receiving repeated ECS following pretreatment with methamphetamine showed significant improvement in PPI and NORT, but not in behavioral sensitization. In the CPP study, the ECS-treated animals achieved extinction of place preference, but relapsed after a low-dose reinstatement of methamphetamine. Conclusions: The results indicated that repeated ECS treatments can ameliorate impairment to the sensorimotor gating and recognition memory elicited by methamphetamine, and temporarily suppress the reinforcement induced by methamphetamine in mice. Our findings suggest electroconvulsive therapy (ECT) may have potential applications with regard to the treatment of methamphetamine psychosis and addiction. [ABSTRACT FROM AUTHOR]

Abstract: Synaptogyrin 1 gene (SYNGR1) is considered as a positional candidate gene for schizophrenia because of its location at chromosome 22q13, a region linked to schizophrenia, and its reduced expression in postmortem brain of patients with schizophrenia. Additionally, genetic studies also reported association of SYNGR1 is with schizophrenia and bipolar disorder in southern India. Prompted by these findings, we were interested to know if SYNGR1 is also associated with schizophrenia in our population. Therefore, we systematically searched for SYNGR1 mutations in a cohort of Han Chinese patients from Taiwan. Four single nucleotide polymorphisms (SNPs) were identified, including three at the putative core promoter region (g.-673A>C, g.-377G>A and g.-318G>T) that are in strong linkage disequilibrium and one in intron 2 (IVS2-64C>G). Computer program predicts that g.-637A>C and g.318G>T may change transcription binding sites of AP-1 and TGT3, respectively. We further carried out SNP- and haplotype-based case-control association studies of these tress SNPs with schizophrenia. However, no association was detected between these SNPs and schizophrenia in our sample. Nevertheless, we identified several rare mutations in exon 6 of SYNGR1 gene in our patient cohort (n =497), including a 3-bp (AAC) in-frame insertion between codon 202 and 203 (P202_T203insN) in two patients, an A-to-G missense mutation (c.665A>G) at codon 222 (D222G) in one patient, a synonymous mutation (c.669C>T) at codon 223 (T223T) in one patient, and a C-to-T at 3′ UTR of SYNGR1 (c.772C>T) in one patient. These are mutations were not found in 507 control subjects, suggesting further functional assays are warranted to verify their relevance to the pathogenesis of schizophrenia. [Copyright &y& Elsevier]

Abstract: Long-term administration of antipsychotic drugs can induce differential expression of various proteins in brain cells, which may underscore the molecular mechanism of their clinical efficacy and/or side effects. We used two-dimensional gel electrophoresis in combination with mass spectrometry to screen differentially expressed proteins in the brain cells of rats under chronic clozapine treatment. We identified a protein, transthyretin, which was significantly up-regulated in the hippocampus of rats after four weeks’ treatment of clozapine (20mg/kg) as compared with control animals. Western blot analysis further supported this finding. Besides, we also observed increased transcription of transthyretin mRNA in the cerebral cortex of rats under chronic treatment of clozapine (20mg/kg) or olanzapine (2mg/kg), but not haloperidol (1mg/kg), using real-time quantitative PCR. Transthyretin is a retinol carrier protein, our findings suggest that antipsychotic drugs treatment may affect the retinoid signaling cascade in the brain. Besides, transthyretin is also an indicator of nutritional status; increased transthyretin may be associated with the body weight gain of taking atypical antipsychotic drugs. This study also demonstrates that comparative proteome analysis is a feasible method to study the molecular mechanism of chronic antipsychotic drugs treatment. [Copyright &y& Elsevier]

Abstract: Chronic antipsychotic drugs treatment may regulate the expression of a variety of genes in the brain, which may underscore their clinical efficacy and/or side effects. In this study, we measured the mRNA levels of three genes encoding the catabolic enzymes of biogenic amine neurotransmitters, i.e., monoamine oxidase A (MAOA), B (MAOB) and catechol O-methyltransferase (COMT), in rat frontal cortex following 4 weeks’ treatment of various antipsychotic drugs using quantitative PCR. Significantly elevated mRNA levels of MAOB and COMT were first observed in frontal cortex of rats treated with risperidone (1mg/kg) when compared to control animals. Further study showed that chronic treatment of olanzapine (2mg/kg), but not haloperidol (1mg/kg) or clozapine (20mg/kg), resulted in significantly increased mRNA levels of MAOA, MAOB and COMT in rat frontal cortex as compared to control animals. These results indicate that chronic treatment of different antipsychotic drugs may differentially regulate the gene expression of three catabolic enzymes of biogenic amine neurotransmitters, and which may partly account for the molecular mechanism of their different clinical efficacy. [Copyright &y& Elsevier]

Abstract: Reelin is an extracellular matrix glycoprotein that plays an important role in guiding neuronal migration, lamination and connection during embryonic brain development. Several reports suggest that reduced reelin expression is associated with human mental illnesses such as schizophrenia, mood disorders and autism. Human reelin cDNA has been cloned and contains a polymorphic GGC repeat at the 5′ untranslated region. In view of the possible regulation of reelin gene expression by this GGC polymorphism, we investigated the association of the polymorphic GGC repeat with schizophrenia in a Chinese Han population from Taiwan. We found no differences of allelic and genotypic distributions of the polymorphic GGC triplets between 162 schizophrenic patients and 176 controls in this study. Our findings do not support the involvement of the polymorphic GGC triplets of the reelin gene in the pathogenesis of schizophrenia in the population studied. [Copyright &y& Elsevier]

Methamphetamine (METH) is a highly addictive psychostimulant that may cause long-lasting synaptic dysfunction and abnormal gene expression. We aimed to explore the differential expression of synaptic plasticity genes in chronic METH-treated mouse brain. We used the RT 2 Profiler PCR Array and the real-time quantitative PCR to characterize differentially expressed synaptic plasticity genes in the frontal cortex and the hippocampus of chronic METH-treated mice compared with normal saline-treated mice. We further used pyrosequencing to assess DNA methylation changes in the CpG region of the five immediate early genes (IEGs) in chronic METH-treated mouse brain. We detected six downregulated genes in the frontal cortex and the hippocampus of chronic METH-treated mice, including five IEGs ( Arc , Egr2 , Fos , Klf10 , and Nr4a1 ) and one neuronal receptor gene ( Grm1 ), compared with normal saline-treated group, but only four genes ( Arc , Egr2 , Fos , and Nr4a1 ) were confirmed to be different. Furthermore, we found several CpG sites of the Arc and the Fos that had significant changes in DNA methylation status in the frontal cortex of chronic METH-treated mice, while the klf10 and the Nr4a1 that had significant changes in the hippocampus. Our results show that chronic administration of METH may lead to significant downregulation of the IEGs expression in both the frontal cortex and the hippocampus, which may partly account for the molecular mechanism of the action of METH. Furthermore, the changes in DNA methylation status of the IEGs in the brain indicate that an epigenetic mechanism-dependent transcriptional regulation may contribute to METH addiction, which warrants additional study. [ABSTRACT FROM AUTHOR]