Cross-cultural Validation of the 5-Factor Structure of Negative Symptoms in Schizophrenia.

Objective: Negative symptoms are currently viewed as having a 2-dimensional structure, with factors reflecting diminished expression (EXP) and motivation and pleasure (MAP). However, several factor-analytic studies suggest that the consensus around a 2-dimensional model is premature. The current study investigated and cross-culturally validated the factorial structure of BNSS-rated negative symptoms across a range of cultures and languages. Method: Participants included individuals diagnosed with a psychotic disorder who had been rated on the Brief Negative Symptom Scale (BNSS) from 5 cross-cultural samples, with a total N = 1691. First, exploratory factor analysis was used to extract up to 6 factors from the data. Next, confirmatory factor analysis evaluated the fit of 5 models: (1) a 1-factor model, 2) a 2-factor model with factors of MAP and EXP, 3) a 3-factor model with inner world, external, and alogia factors; 4) a 5-factor model with separate factors for blunted affect, alogia, anhedonia, avolition, and asociality, and 5) a hierarchical model with 2 second-order factors reflecting EXP and MAP, as well as 5 first-order factors reflecting the 5 aforementioned domains. Results: Models with 4 factors or less were mediocre fits to the data. The 5-factor, 6-factor, and the hierarchical second-order 5-factor models provided excellent fit with an edge to the 5-factor model. The 5-factor structure demonstrated invariance across study samples. Conclusions: Findings support the validity of the 5-factor structure of BNSS-rated negative symptoms across diverse cultures and languages. These findings have important implications for the diagnosis, assessment, and treatment of negative symptoms

Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

Abstract Background Our previous work shows that increased matrix stiffness not only alters malignant characteristics of hepatocellular carcinoma (HCC) cells, but also attenuates metformin efficacy in treating HCC cells. Here, we identified differential membrane proteins related to matrix stiffness-mediated metformin resistance for better understand therapeutic resistance of metformin in HCC. Methods Differential membrane proteins in HCC cells grown on different stiffness substrates before and after metformin intervention were screened and identified using isobaric tags for relative and absolute quantification (iTRAQ) labeling coupled with the liquid chromatography-tandem mass spectrometry (LC–MS/MS), then bioinformatic analysis were applied to determine candidate membrane protein and their possible signaling pathway. Results A total of 5159 proteins were identified and 354 differential membrane proteins and membrane associated proteins, which might be associated with matrix stiffness-mediated metformin resistance were discovered. Then 94 candidate membrane proteins including 21 up-regulated protein molecules and 73 down-regulated protein molecules were further obtained. Some of them such as Annexin A2 (ANXA2), Filamin-A (FLNA), Moesin (MSN), Myosin-9 (MYH9), Elongation factor 2 (eEF2), and Tax1 binding Protein 3 (TAX1BP3) were selected for further validation. Their expressions were all downregulated in HCC cells grown on different stiffness substrates after metformin intervention. More importantly, the degree of decrease was obviously weakened on the higher stiffness substrate compared with that on the lower stiffness substrate, indicating that these candidate membrane proteins might contribute to matrix stiffness-mediated metformin resistance in HCC. Conclusions There was an obvious change in membrane proteins in matrix stiffness-mediated metformin resistance in HCC cells. Six candidate membrane proteins may reflect the response of HCC cells under high stiffness stimulation to metformin intervention, which deserve to be investigated in the future

Genetic Variation and Phylogeography of <i>Lumbriculus variegatus</i> (Annelida: Clitellata: Lumbriculidae) Based on Mitochondrial Genes

Lumbriculus variegatus is a typical cold-water worm and is mainly distributed in the Tibetan Plateau and Northeast in China. The current study aimed to explore the genetic diversity and phylogeography of L. variegatus sampled from different geographical regions based on concatenated (COI + 16S rRNA, 879 bp) genes. Among 63 L. variegatus specimens, 29 haplotypes were identified with high haplotype diversity (h = 0.923) and nucleotide diversity (π = 0.062). The Bayesian phylogenetic analysis and Median-joining haplotype network revealed two lineages, or species, of L. variegatus. Taxa belonging to lineage I was mainly distributed in the Tibetan Plateau of China, North America, and Sweden, while lineage II composed taxa from Northeast China, southern China, and Sweden. The analysis of molecular variance indicated that the genetic difference was mainly due to differences between lineages. Neutrality tests showed that the overall L. variegatus have a stable population since the time of origin. Divergence time analysis suggested that L. variegatus originated from the Triassic period of Mesozoic in 235 MYA (95%HPD: 199–252 MYA), and the divergence between different lineages of L. variegatus began from the next 170 million years

Enhanced on-off keying modulation for wireless power transfer systems to improve efficiency over a wide load range

Maximum efficiency point tracking (MEPT) is a key concept to improve the ac-ac efficiency of the wireless power transfer (WPT) systems by controlling the equivalent load impedance with a dc-dc converter or an active rectifier. The on-off keying (OOK) modulation can reduce the switching losses of the converters to achieve MEPT but generates relatively large dc voltage ripples. In order to solve this problem, this article proposes an enhanced on-off keying (EOOK) modulation method by adding a half-bridge mode based on OOK modulation for WPT systems. By combining the three operation modes, both the inverter and the active rectifier can operate in full-bridge-half-bridge mode or half-bridge-zero mode to adapt to different power levels and achieve MEPT simultaneously. Meanwhile, the ZVS condition and the low voltage ripple are achieved as well. The circuit model of the proposed method is analyzed to derive the equivalent load resistance, the output voltage gain, and the output power with respect to the modulation of EOOK. The reason for output voltage ripples and the power losses on both the transmitting and receiving sides are also revealed. An experimental prototype is built to verify the effectiveness of the proposed method. The experimental results show that the proposed method can maintain constant voltage output and achieve MEPT as well as ZVS operation, with high efficiency of up to 94.761% over a wide range of load conditions. © 1967-2012 IEEE

Influence of Glass Phase in Silver Paste on Metallized Contact Resistance between Rear Silver and Aluminum Electrodes of Crystalline Silicon PERC Cells

In the back-side metallization process of the passivated emitter and rear cell (PERC), the contact between the Ag rear electrode and Al rear electrode is an important factor for cell efficiency. In this paper, we report on the effect of Ag paste containing two types of oxide glass frit, V-B-Te and Pb-B-Si, on the Ag/Al contact, owing to their remarkable contrast with regard to the Ag/Al contact resistance. By combining the observation of the Ag/Al interface structure with the investigation on the interaction between glass and Al, glass transition temperature, and the distribution of glass phase in the Ag electrode, the influence of the glass phase on the contact resistance between rear Ag and Al electrodes was clearly elucidated

Additional file 5 of Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

Additional file 5: Figure S2. Six typical expression patterns reflect the increase degree of membrane proteins. iTRAQ tags 113, 114, 115, 116, 117 and 118 represent NC-L, NC-M, NC-H, Met-L, Met-M and Met-H, respectively

Additional file 3 of Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

Additional file 3: Table S2. A list of all identified proteins

Additional file 2 of Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

Additional file 2: Figure S1. Efficiency and quality identification of membrane protein extraction. (A) The approximate location and range of membrane protein molecules performed by polyacrylamide gel electrophoresis with Coomassie brilliant blue staining. (B)(i, ii) Western blot were performed on the six groups of membrane proteins and cytoplasmic proteins

Additional file 1 of Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

Additional file 1: Table S1. Ingredients of polyacrylamide gel substrates with variable stiffness