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Objective: To analyze whether metformin treatment in patients with polycystic ovary syndrome (PCOS) results in a decrease of anti-Müllerian hormone (AMH) levels, we reviewed and analyzed PCOS studies which evaluated serum AMH levels before and after metformin treatment. Methods: This is a systematic review and meta-analysis of self-controlled clinical trials. Databases including PubMed, Embase, and Web of Science library were searched to identify eligible studies published before February 2023. Random-effects models were applied to assess standardized mean differences (SMDs) with 95% confidence intervals (95% CI). Results: The electronic-based search retrieved 167 articles of which 14 studies (12 publications) involving 257 women with PCOS were included. In general, AMH levels decreased significantly after metformin treatment [SMD (95% CI) of -0.70 (-1.13 to -0.28); P = 0.001]. Metformin exhibited a strong inhibitory effect on AMH levels for PCOS patients with age less than 28 [SMD − 1.24, 95% CI − 2.15 to − 0.32, P = 0.008]. Additionally, AMH levels significantly slid down in PCOS patients with no more than 6 months metformin treatment [SMD − 1.38, 95% CI − 2.18 to − 0.58, P = 0.0007], or with no more than a dose of 2000 mg/day [SMD -0.70, 95% CI -1.11 to -0.28; P = 0.001]. Notably, suppressive effects of metformin treatment were merely observed in patients with AMH levels at baseline higher than 4.7 ng/ml [SMD − 0.66, 95% CI − 1.02 to − 0.31, P = 0.0003]. Conclusion: This meta-analysis provided quantitative evidence demonstrating that metformin significantly decreased AMH levels, especially for young patients and those with AMH levels at baseline higher than 4.7 ng/ml. Trial registration: PROSPERO CRD42020149182. [ABSTRACT FROM AUTHOR]

Acoustic logging instruments generate high voltages in the order of thousands of volts. Electrical interferences are thus induced by high-voltage pulses that affect the logging tool and make it inoperable owing to damaged components in severe cases. High-voltage pulses from the acoustoelectric logging detector interfere with the electrode measurement loop through capacitive coupling, which has seriously affected the acoustoelectric signal measurements. In this paper, we simulate high voltage pulses, capacitive coupling and electrode measurement loops based on qualitative analysis of the causes of electrical interference. Based on the structure of the acoustoelectric logging detector and the logging environment, an electrical interference simulation and prediction model was developed to quantify the characteristics of the electrical interference signal. [ABSTRACT FROM AUTHOR]

Cu and Zn are common and potentially harmful heavy metals to plants, animals and humans. Herein, we investigated the effects of Cu and Zn stress on the photosynthesis and tolerance mechanism of alfalfa plants to ROS using fluorescence and biochemical methods. The results showed that Cu stress significantly reduced the chlorophyll content of the leaves, while Zn stress only reduced the Chl a content. The Fv/Fm decreased significantly under Cu stress but was not affected by Zn treatment. However, the PIABS of the leaves were sensitive to Cu and Zn stress. Both Cu and Zn stress resulted in the weakening of the ability of PQ library to accept electrons, the damage of OEC and the inhibition of the electron transfer from QA- to QB. Moreover, Cu stress also dissociated the thylakoids of leaves, but Zn stress did not significantly damage it. In Cu and Zn stressed leaves, the reduction of RC/CSm significantly increased the ABS/RC and TRo/RC values. When the stress intensified, the value of DIo/RC increased indicated a plant self-protection mechanism that eliminates excess energy in the PSII reaction center and increases the energy for heat dissipation per unit reaction center. Cu stress significantly increased the O2- production rate, H2O2 content, and MDA accumulation in the leaves. However, Zn stress exhibited a minimal effect on the ROS production and oxidative damage in the alfalfa leaves but increased the O2- production rate at the concentration of 800 μmol·L−1. Cu stress increased the activities of SOD, POD, CAT, APX, and GPX in the leaves; however, leaves adapts to Zn stress by enhancing the activities of SOD and GPX. Thus under Cu stress, the degree of photoinhibition and oxidative damage in alfalfa leaves were significantly higher than under Zn stress. [ABSTRACT FROM AUTHOR]

Perioperative neurocognitive disorder (PND) frequently occurs in elderly patients following anesthesia, and is associated with pro-inflammatory activation of microglia in hippocampus. In this study, sevoflurane, a commonly used inhaled anesthetic in clinic, was used to induce PND-like symptoms in aged SD rats (18–20 months). Data from novel object recognition and Y-maze tests first confirmed that aged SD rats exposed to 2% sevoflurane for 5 h developed cognitive impairment. Microglia preferred to polarizing towards pro-inflammatory M1 subtype (iNOS+Iba-1 +) in rat hippocampus post sevoflurane exposure, but not anti-inflammatory M2 subtype (Arg-1 +Iba-1 +). Microarray data identified interferon regulatory factor 6 (Irf6) as one (Fold change = −2.52, p = 0.006) of the 15 downregulated genes in hippocampus of the rats exposed to sevoflurane. Co-immunofluorescence data further illustrated that sevoflurane decreased Irf6 expression in hippocampal microglia. In vitro, sevoflurane enhanced lipopolysaccharide-induced M1 polarization of BV-2 cells and inhibited interleukin-4 induced M2 polarization. Interestingly, manipulation of Irf6 expression hardly affected M1 polarization. However, Irf6 overexpression further augmented the inhibitory effects on M2 polarization, and its silencing showed opposite effects. In addition, such M2 polarization-promoting effects of Irf6 knockdown may be associated with induction of peroxisome proliferator activated receptor gamma expression. Collectively, these findings suggest that Irf6 downregulation in hippocampal microglia may be a compensatory mechanism against sevoflurane-induced PND in the elderly. • Microarray analyses the altered mRNA expression in sevoflurane-exposed aged rats. • Irf6 is unaffected on sevoflurane-stimulated microglia M1 polarization. • Irf6 inhibits microglia M2 polarization via suppressing PPARγ expression. [ABSTRACT FROM AUTHOR]

Employing multi-antenna rate-splitting (RS) at the transmitter and successive interference cancellation (SIC) at the receivers, has emerged as a powerful transceiver strategy for multi-antenna networks. In this paper, we design RS precoders for an overloaded multicarrier multigroup multicast downlink system, and analyse the error performance. RS splits each group message into degraded and designated parts. The degraded parts are combined and encoded into a degraded stream, while the designated parts are encoded in designated streams. All streams are precoded and superimposed in a non-orthogonal fashion before being transmitted over the same time-frequency resource. We first derive the optimized RS-based precoder, where the design philosophy is to achieve a fair user group rate for the considered scenario by solving a joint max-min fairness and sum subcarrier rate optimization problem. Comparing with other precoding schemes including the state-of-the-art multicast transmission scheme, we show that the RS precoder outperforms its counterparts in terms of the fairness rate, with Gaussian signalling, i.e., idealistic assumptions. Then we integrate the optimized RS precoder into a practical transceiver design for link-level simulations (LLS), with realistic assumptions such as finite alphabet inputs and finite code block length. The performance metric becomes the coded bit error rate (BER). In the system under study, low-density parity-check (LDPC) encoding is applied at the transmitter, and iterative soft-input soft-output detection and decoding are employed at the successive interference cancellation based receiver, which completes the LLS processing chain and helps to generate the coded error performance results which validate the effectiveness of the proposed RS precoding scheme compared with benchmark schemes, in terms of the error performance. More importantly, we unveil the corresponding relations between the achievable rate in the idealistic case and coded BER in the realistic case, e.g., with finite alphabet input, for the RS precoded multicarrier multigroup multicast scenario. [ABSTRACT FROM AUTHOR]

Key message: Compared with NaCl, NaHCO3 caused more serious oxidative damage and photosynthesis inhibition in safflower by down-regulating the expression of related genes. Salt-alkali stress is one of the important factors that limit plant growth. NaCl and sodium bicarbonate (NaHCO3) are neutral and alkaline salts, respectively. This study investigated the physiological characteristics and molecular responses of safflower (Carthamus tinctorius L.) leaves treated with 200 mmol L−1 of NaCl or NaHCO3. The plants treated with NaCl treatment were less effective at inhibiting the growth of safflower, but increased the content of malondialdehyde (MDA) in leaves. Meanwhile, safflower alleviated stress damage by increasing proline (Pro), soluble protein (SP), and soluble sugar (SS). Both fresh weight and dry weight of safflower was severely decreased when it was subjected to NaHCO3 stress, and there was a significant increase in the permeability of cell membranes and the contents of osmotic regulatory substances. An enrichment analysis of the differentially expressed genes (DEGs) using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes identified significant enrichment of photosynthesis and pathways related to oxidative stress. Furthermore, a weighted gene co-expression network analysis (WGCNA) showed that the darkgreen module had the highest correlation with photosynthesis and oxidative stress traits. Large numbers of transcription factors, primarily from the MYB, GRAS, WRKY, and C2H2 families, were predicted from the genes within the darkgreen module. An analysis of physiological indicators and DEGs, it was found that under saline-alkali stress, genes related to chlorophyll synthesis enzymes were downregulated, while those related to degradation were upregulated, resulting in inhibited chlorophyll biosynthesis and decreased chlorophyll content. Additionally, NaCl and NaHCO3 stress downregulated the expression of genes related to the Calvin cycle, photosynthetic antenna proteins, and the activity of photosynthetic reaction centers to varying degrees, hindering the photosynthetic electron transfer process, suppressing photosynthesis, with NaHCO3 stress causing more pronounced adverse effects. In terms of oxidative stress, the level of reactive oxygen species (ROS) did not change significantly under the NaCl treatment, but the contents of hydrogen peroxide and the rate of production of superoxide anions increased significantly under NaHCO3 stress. In addition, treatment with NaCl upregulated the levels of expression of the key genes for superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), the ascorbate-glutathione cycle, and the thioredoxin-peroxiredoxin pathway, and increased the activity of these enzymes, thus, reducing oxidative damage. Similarly, NaHCO3 stress increased the activities of SOD, CAT, and POD and the content of ascorbic acid and initiated the glutathione-S-transferase pathway to remove excess ROS but suppressed the regeneration of glutathione and the activity of peroxiredoxin. Overall, both neutral and alkaline salts inhibited the photosynthetic process of safflower, although alkaline salt caused a higher level of stress than neutral salt. Safflower alleviated the oxidative damage induced by stress by regulating its antioxidant system. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hybrid nanostructure consisted of graphene oxide encapsulating α-MnO 2 nanofiber was fabricated. • The mineralization efficiency of TBBPA could reach 79.50% by α-MnO 2 @GO/ PMS system. • The introduction of graphene oxide increases the specific surface area and Mn(III) content of α-MnO 2. • Graphene oxide can effectively modify the surface electronic properties and promote the production of reactive oxygen species. • The synergistic action of oxygen vacancy and hydroxyl radical results in the efficient degradation of TBBPA. The development of efficient and environmentally friendly catalysts for activating persulfate is the focus of advanced oxidation treatment of organic contaminants. Manganese dioxide (MnO 2), which has a multivalent nature and is a low-toxic natural stock, has the ability to immediately oxidize pollutants. In order to further improve its catalytic performance, the α-MnO 2 nanofiber coated with graphene oxide (α-MnO 2 @GO) was prepared by one-step hydrothermal method, and worked as a peroxmonsulfate (PMS) activator for efficient degradation of tetrabromobisphenol A (TBBPA). The structure characterization results indicate that α-MnO 2 nanofibers are successfully encapsulated by graphene and assembled into a three-dimensional layered structure. The factors affecting the catalytic degradation of TBBPA by this catalyst are investigated in detail. Under optimal conditions, the highest removal ratio of TBBPA could reach 100% after treatment of 20 min by α-MnO 2 @GO/PMS system, and a good mineralization efficiency of up to 79.50% is obtained. Electron paramagnetic resonance detection combined with quenching experiments showed that sulfate radical and hydroxyl radical played a role in the degradation of TBBPA. Based on X-ray photoelectron spectroscopy and free radical scavenging experiments, the peroxmonsulfate activation mechanism by α-MnO 2 @GO was proposed. Finally, based on the discovered intermediates, two potential TBBPA degradation routes using this catalyst were suggested. This study not only provides a new strategy for improving the catalytic activity of MnO 2 but also sheds new insight into the application of eco-friendly natural stock for environmental remediation. [ABSTRACT FROM AUTHOR]

In this article, we investigate a resource allocation problem for multicarrier multiuser MISO (multiple-input-Single-output) downlink systems, where multiple co-channel multicast groups are served simultaneously. We consider a rate-splitting transmission scheme to address the inevitable inter-group interference under an overloaded multigroup multicast scenario, where the insufficient number of transmit antennas prevents the conventional schemes from neutralizing the interference. We first formulate an optimization problem for maximizing the minimum multicast group rate among all groups on all available subcarriers. This problem involves a joint power and subcarrier allocation optimization, and is non-convex. We apply an iterative scheme based on successive convex approximation (SCA) to find the locally optimal solution. Simulation results demonstrate the performance gain of the proposed scheme compared to the state-of-the-art transmission schemes. [ABSTRACT FROM AUTHOR]

Accurate measurement of grid frequency timely is essential to the stable operation of a grid network and the performance of a grid-connected converter. When harmonic pollution exists in the power system, indexes of timeliness, accuracy, and noise rejection performance are required to be considered synthetically. However, these indexes are usually difficult to be taken care of at the same time, and problems of convergence and stability should also be considered. In order to calculate grid frequency precisely and timely, this paper proposes a grid frequency measurement method. A three-level function of the grid voltage signal is defined step by step. On the basis of the function, equations with the signal's frequency and amplitude as two unknowns are established. Finally, a system of equations is obtained and solved in order to calculate grid frequency. The proposed method calculates grid frequency precisely through strict theoretical derivation, possesses a strong anti-disturbance ability against harmonics, and is simple for realization. In addition, because of the absence of iteration and feedback calculation, problems of convergence property as well as stability do not exist. Effectiveness of this method is proved through simulation and experiment. [ABSTRACT FROM AUTHOR]

Interleukin-33 (IL-33), an emerging cytokine within the IL-1 family, assumes a pivotal function in the control of obesity. However, the specific mechanism of its regulation of obesity formation remains unclear. In this study, we found that the expression level of IL-33 increased in visceral adipose tissue in mice fed with a high-fat diet (HFD) compared with that in mice fed with a normal diet (ND). In vitro, we also found the expression level of IL-33 was upregulated during the adipogenesis of 3T3-L1 cells. Functional test results showed that knockdown of IL-33 in 3T3-L1 cells differentiation could promote the accumulation of lipid droplets, the content of triglyceride and the expression of adipogenic–related genes (i.e. PPAR-γ, C/EBPα, FABP4, LPL, Adipoq and CD36). In contrast, overexpression of IL-33 inhibits adipogenic differentiation. Meanwhile, the above tests were repeated after over-differentiation of 3T3-L1 cells induced by oleic acid, and the results showed that IL-33 played a more significant role in the regulation of adipogenesis. To explore the mechanism, transcriptome sequencing was performed and results showed that IL-33 regulated the PPAR signaling pathway in 3T3-L1 cells. Further, Western blot and confocal microscopy showed that the inhibition of IL-33 could promote PPAR-γ expression by inhibiting the Wnt/β-catenin signal in 3T3-L1 cells. This study demonstrated that IL-33 was an important regulator of preadipocyte differentiation and inhibited adipogenesis by regulating the Wnt/β-catenin/PPAR-γ signaling pathway, which provided a new insight for further research on IL-33 as a new intervention target for metabolic disorders. [ABSTRACT FROM AUTHOR]

Hepatic insulin resistance and hepatosteatosis in diet‐induced obesity are associated with various metabolic diseases, yet the underlying mechanisms remain to be fully elucidated. Here we show that the expression levels of the disulfide‐bond A oxidoreductase‐like protein (DsbA‐L) are significantly reduced in the liver of obese mice and humans. Liver‐specific knockout or adenovirus‐mediated overexpression of DsbA‐L exacerbates or alleviates, respectively, high‐fat diet–induced mitochondrial dysfunction, hepatosteatosis, and insulin resistance in mice. Mechanistically, we found that DsbA‐L is localized in mitochondria and that its deficiency is associated with impairment of maximum respiratory capacity, elevated cellular oxidative stress, and increased JNK activity. Our results identify DsbA‐L as a critical regulator of mitochondrial function, and its down‐regulation in the liver may contribute to obesity‐induced hepatosteatosis and whole body insulin resistance.—Chen, H., Bai, J., Dong, F., Fang, H., Zhang, Y., Meng, W., Liu, B., Luo, Y., Liu, M., Bai, Y., Abdul‐Ghani, M. A., Li, R., Wu, J., Zeng, R., Zhou, Z., Dong, L. Q., Liu, F. Hepatic DsbA‐L protects mice from diet‐induced hepatosteatosis and insulin resistance. FASEB J. 31, 2314–2326 (2017). www.fasebj.org [ABSTRACT FROM AUTHOR]

Avian influenza viruses of subtype H9N2 are widely prevalent in poultry in many Asian countries, and the segmented nature of the viral genome results in multiple distinct genotypes via reassortment. In this study, genetic evolution of H9N2 viruses circulating in eastern China during 2007–2013 was analyzed. The results showed that the diversity of the gene constellations generated six distinct genotypes, in which a novel genotype (S) bearing the backbone of A/chicken/Shanghai/F/98-like viruses by acquiring A/quail/Hong Kong/G1/97-like polymerase basic subunit 2 and matrix genes has gradually established its ecological niche and been consistently prevalent in chicken flocks in eastern China since its first detection in 2007. Furthermore, genotype S possessed the peculiarity to donate most of its gene segments to other emerging influenza A viruses in China, including the novel reassortant highly pathogenic avian influenza H5N2, the 2013 novel H7N7, H7N9 and the latest reassortant H10N8 viruses, with potential threat to poultry industry and human health. [ABSTRACT FROM AUTHOR]

H9N2 influenza viruses continue to circulate in wild birds and poultry in Eurasian countries and have repeatedly infected mammals, including pigs and humans, posing a significant threat to public health. To understand the adaptation of H9N2 influenza viruses to mammals, we serially passaged a nonpathogenic duck-origin H9N2 influenza virus, A/duck/Jiangsu/1/2008 (DK1), in mouse lungs. Increased virulence was detectable after five sequential passages, and a highly pathogenic mouse-adapted strain (DK1-MA) with a 50 % mouse lethal dose of 10 50 % egg infectious dose was obtained after 18 passages. DK1-MA grew faster and reached significantly higher titers than DK1 in mouse lungs and could sporadically spread to other organs. Moreover, DK1-MA induced a greater magnitude of pulmonary edema and higher levels of inflammatory cellular infiltration in bronchoalveolar lavage fluids than DK1 did. Genomic sequence alignment revealed eight amino acid substitutions (HA-L80F, HA-N193D, NA-A27T, PB2-F404L, PA-D3V, PA-S225R, NP-V105M, M1-A166V) in six viral proteins of DK1-MA compared with DK1 virus. Except for HA-L80F, the other seven substitutions were all located in known functional regions involved in interaction of viral proteins or interaction between the virus and host factors. Taken together, our results suggest that multiple amino acid substitutions may be involved in the adaptation of H9N2 avian influenza virus to mice, resulting in lethal infection, enhanced viral replication, severe pulmonary edema, and excessive inflammatory cellular infiltration in lungs. These observations provide helpful insights into the pathogenic potential of H9N2 avian influenza viruses that could pose threats to human health in the future. [ABSTRACT FROM AUTHOR]

Seipin deficiency is an important cause of type 2 Berardinelli-Seip congenital dyslipidemia (BSCL2). BSCL2 is a severe lipodystrophy syndrome with lack of adipose tissue, hepatic steatosis, insulin resistance, and normal or higher bone mineral density. Bone marrow mesenchymal stem cells (BMSCs) are believed to maintain bone and fat homeostasis by differentiating into osteoblasts and adipocytes. We aimed to explore the role of seipin in the osteogenic/adipogenic differentiation balance of BMSCs. Seipin loxP/loxP mice are used to explore metabolic disorders caused by seipin gene mutations. Compared with wild-type mice, subcutaneous fat deficiency and ectopic fat accumulation were higher in seipin knockout mice. Microcomputed tomography of the tibia revealed the increased bone content in seipin knockout mice. We generated seipin-deficient BMSCs in vitro and revealed that lipogenic genes are downregulated and osteogenic genes are upregulated in seipin-deficient BMSCs. In addition, peroxisome proliferator-activated receptor gamma (PPARγ) signaling is reduced in seipin-deficient BMSCs, while using the PPARγ activator increased the lipogenic differentiation and decreased osteogenic differentiation of seipin-deficient BMSCs. Our findings indicated that bone and lipid metabolism can be regulated by seipin through modulating the differentiation of mesenchymal stem cells. Thus, a new insight of seipin mutations in lipid metabolism disorders was revealed, providing a prospective strategy for MSC transplantation-based treatment of BSCL2. [ABSTRACT FROM AUTHOR]

This paper provides a detailed performance analysis of the physical layer of two state-of-the-art point-to-multipoint (PTM) technologies: evolved Multimedia Broadcast Multicast Service (eMBMS) and Advanced Television Systems Committee - Third Generation (ATSC 3.0). The performance of these technologies is evaluated and compared using link-level simulations, considering relevant identified scenarios. A selection of Key Performance Indicators for the International Mobile Telecommunications 2020 (IMT-2020) evaluation process has been considered. Representative use cases are also aligned to the test environments as defined in the IMT-2020 evaluation guidelines. It is observed that ATSC 3.0 outperforms both eMBMS solutions, i.e., MBMS over Single Frequency Networks (MBSFN) and Single-Cell PTM (SC-PTM) in terms of spectral efficiency, peak data rate and mobility, among others. This performance evaluation serves as a benchmark for comparison with a potential 5G PTM solution. [ABSTRACT FROM AUTHOR]

The 2020 Scott Helt Memorial Award was awarded to Manuel Fuentes, Hongzhi Chen, Eduardo Garro, Jose Luis Carcel, David Vargas, Belkacem Mouhouche, David Gomez-Barquero for their paper, “Physical Layer Performance Evaluation of LTE-Advanced Pro Broadcast and ATSC 3.0 Systems.” The papers appeared in the IEEE Transactions on Broadcasting, vol. 65, no. 3, pp. 477–488, September 2019. The purpose of the IEEE Scott Helt Memorial Award is to recognize exceptional publications in the field and to stimulate interest in and encourage contributions to the fields of interest of the Society. [ABSTRACT FROM AUTHOR]

The diagnosis of primary angiosarcoma of ovary is still a challenge as it has no specific clinical symptoms and is easily confused with other malignant neoplasms in morphology. Here, we described a case of primary ovarian angiosarcoma and reviewed the literature. A 47-year-old female showed a left ovary mass. Grossly, the cut surface of the tumor was solid and gray-white with intermediate texture. Some areas were spongy and atropurpureus with a soft texture. Microscopically, the tumor cells were arranged into a variety of different structures with visible hemorrhage. Immunochemically, the tumor cells were positive for CD31, ERG, Fli1, D2–40 and vimentin in a strong and diffused manner. CD34 stain showed focal positivity. Epithelial markers (e.g. CK, CK7, CK8/18 and PAX8) were all negative. Negative immunostaining for SMA, S-100, P53 and calretinin also were detected. The proliferative index (Ki-67) was approximately 40%. After surgery, the patient was treated with radiotherapy, targeted therapy and immunotherapy. In the 9-month follow-up, the patient was survival without evidence of disease. The diagnosis of ovarian angiosarcoma required the careful observation of morphology and the reasonable application of immunohistochemistry. Targeted therapy and immunotherapy are the potential directions for the treatment of angiosarcoma. [ABSTRACT FROM AUTHOR]

Accurately estimating rock joint roughness is crucial for understanding the shear mechanism and permeability behavior of a rock mass. Several influencing factors, including anisotropy, measurement noise, and the scale effect and sampling interval, have been considered. However, little attention is paid to the influences of nonstationary features on the roughness assessment. In this study, a portable laser scanner was employed to collect high-density 3D point clouds of ten natural rock joint specimens. Based on two parameters, namely, the bright area percentage (BAP) and θ*max/(C + 1), where θ*max is the maximum apparent dip angle and C is a dimensionless fitting parameter, the rock joint roughness was determined before and after removing nonstationary features, and a comparison showed that nonstationary features have a considerable influence on the roughness. Subsequently, an approach was proposed to remove nonstationary features through the conversion of spatial coordinates, and an application to a roughness evaluation illustrated that similar trends are observed between the BAP and θ*max/(C + 1) with respect to the point clouds of ten rock joints whose nonstationary features were removed. These findings reveal that nonstationary features should be removed to improve the accuracy and comparability of the roughness assessments. [ABSTRACT FROM AUTHOR]

Rapid long-runout landslides always cause extensive damage to lives and properties, and the deposit characteristics of landslides play an important role in revealing the evolution and transport mechanism. Several intensive fieldworks were conducted at the Jiweishan landslide region in Chongqing, China to investigate the deposit features, including the motion characteristics, retention of stratigraphic sequence, inverse grading, and thickness distribution, which later helped in the calibration and setting of the numerical modeling. Based on the discrete element method (DEM), the effects of simulation parameters (friction coefficient, volume, and fall height) on the maximum travel distance and deposit area of the landslide were assessed, taking account into the joints network developed in rock mass, respectively. Sensitivity analysis was performed according to numerical data, and the calculated relative sensitivity (RS) values suggested that all parameters had an impact on the travel distance of rapid long-runout landslides, and the sensitivity could be listed in the following order of most to least sensitive: volume (RS = 0.83) > fall height (RS = 0.23) > friction coefficient (RS = 0.14). [ABSTRACT FROM AUTHOR]

An approach was proposed to automatically measure the discontinuity geometric properties from a point cloud acquired using Light Detection and Ranging (LiDAR). The procedure primarily includes the following features: (Assali et al., 2016) Grid data from the point cloud was created to enhance computational efficiency for data processing and retrieval; (Barton & Choubey, 1977) A modified region growing (MRG) algorithm, which is characterized by more efficient grow criterion, was used to recognize discontinuities from the point cloud; (Cao et al., 2017) Four geometric properties from identified discontinuities were calculated based on analytic geometry; (Chen et al., 2016) Influence of threshold T on the identified results was investigated through sensitivity analysis, and threshold T was suggested to be less than the minimum normal difference among all joints and larger than 0°. Two cases (regular polyhedrons and a tunnel in the Rumei hydropower station) were taken as case studies to validate the developed approach, and calculation results have good agreement with real situations. [ABSTRACT FROM AUTHOR]

We propose GraphD, an out-of-core Pregel-like system targeting efficient big graph processing with a small cluster of commodity PCs connected by Gigabit Ethernet, an environment affordable to most users. This is in contrast to some recent efforts for out-of-core graph computation with specialized hardware. In our setting, a vertex-centric program is often data-intensive, since the CPU cost of calculating a message value is negligible compared with the network cost of transmitting that message. As a result, network bandwidth is usually the bottleneck, and out-of-core execution would not sacrifice performance if disk IO overhead can be hidden by message transmission, which is achieved by GraphD through the parallelism of computation and communication. GraphD streams edge and message data on local disks, and thus consumes negligible memory space. For a broad class of Pregel algorithms where message combiner is applicable, GraphD completely eliminates the need of any expensive external-memory join or group-by, which is required by existing systems such as Pregelix and Chaos. Extensive experiments show that GraphD beats existing out-of-core systems by orders of magnitude, and achieves comparable performance to in-memory systems running with adequate memory. [ABSTRACT FROM PUBLISHER]

Background. Atherosclerosis is a common inflammatory disease. Stem cell and endothelial progenitor cell treatments can improve cardiac function after myocardial infarction. Granulocyte colony-stimulating factor (G-CSF) is a mobilisation agent, mobilising stem cells from the bone marrow to circulation in the blood. G-CSF may constitute a treatment of atherosclerosis. We have conducted meta-analysis to evaluate the current evidence for the effect of G-CSF on the progression of atherosclerosis in animal models and to provide reference for preclinical experiments and future human clinical trials of atherosclerosis treatment. Methods. We searched several databases and conducted a meta-analysis across seven articles using a random-effect model. All statistical analyses were performed using Review Manager Version 5.2 and Stata 12.0. Results. We found that G-CSF therapy was associated with reduced atherosclerotic lesion area (weighted mean difference (WMD): 7.29%; 95% confidence interval (CI): 2.06–12.52%; P=0.006). No significant differences in total serum cholesterol (P=0.54) and triglyceride levels (P=0.95) were noted in G-CSF treatment groups compared with controls. Multivariable metaregression analysis revealed that the animal type (rabbit, P=0.022) and frequency of G-CSF administration (>20, P=0.007) impacted the atherosclerotic lesion area changes. Conclusion. The meta-analysis suggested that G-CSF treatment might inhibit the progression of atherosclerosis in animal models. [ABSTRACT FROM AUTHOR]

Beiging of white adipose tissue has potential antiobesity and antidiabetes effects, yet the underlying signaling mechanisms remain to be fully elucidated. Here we show that adipose-specific knockout of Rheb, an upstream activator of mechanistic target of rapamycin complex 1 (mTORC1), protects mice from high-fat diet-induced obesity and insulin resistance. On the one hand, Rheb deficiency in adipose tissue reduced mTORC1 signaling, increased lipolysis, and promoted beiging and energy expenditure. On the other hand, overexpression of Rheb in primary adipocytes significantly inhibited CREB phosphorylation and uncoupling protein 1 (UCP1) expression. Mechanistically, fat-specific knockout of Rheb increased cAMP levels, cAMP-dependent protein kinase (PKA) activity, and UCP1 expression in subcutaneous white adipose tissue. Interestingly, treating primary adipocytes with rapamycin only partially alleviated the suppressing effect of Rheb on UCP1 expression, suggesting the presence of a novel mechanism underlying the inhibitory effect of Rheb on thermogenic gene expression. Consistent with this notion, overexpression of Rheb stabilizes the expression of cAMP-specific phosphodiesterase 4D5 (PDE4D5) in adipocytes, whereas knockout of Rheb greatly reduced cellular levels of PDE4D5 concurrently with increased cAMP levels, PKA activation, and UCP1 expression. Taken together, our findings reveal Rheb as an important negative regulator of beige fat development and thermogenesis. In addition, Rheb is able to suppress the beiging effect through an mTORC1-independent mechanism. [ABSTRACT FROM AUTHOR]

Conventional scanning probe microscopy (SPM)-based nanomanipulations always have to face scanner accuracy problems such as hysteresis, nonlinearity, and thermal drift. Although some scanners consist of internal position sensors, the sensitivity is not high enough to monitor high-resolution nanomanipulations. Additionally, once the scan size decreases to a nanolevel such as less than 100 nm, the noise brought by sensors is large enough to affect the performance of the closed-loop motion control system. In this paper, a non-vector space control strategy based on compressive feedback is proposed in order to improve the accuracy of SPM-based nanomanipulations. In this approach, local images (or compressive data) are used as both the reference input and feedback for a non-vector space closed-loop controller which considers the local image (or compressive data) as a set. The controller is designed in non-vector space, and it requires no prior information on features or landmarks which are widely used in traditional visual servoing. In this paper, the atomic force microscopy is used as an example of SPM to implement the non-vector space control strategy for nanomanipulations. The motivation of designing such a non-vector space controller is to solve the accuracy problem in nanomanipulation. Without this technique, the SPM-based nanomanipulations, such as nanomeasurement and nanosurgery, are difficult to conduct, with accuracy controlled under several nanometers. In order to illustrate the contributions and potential applications of this non-vector controller, at the end of this paper, an application of carbon nanotube local electrical property characterization based on a non-vector space motion control is shown to clearly verify the concept. Compared with other research in the local electrical property characterization, the non-vector space controller can ensure that the measurement accuracy (position error) is controlled within a few nanometers, which also ensures the reliability of measurement results. Additionally, this non-vector space control method can be implemented into any kind of SPM to realize a real-time control for nanomanipulation such as nanofabrication and nanoassembly. [ABSTRACT FROM PUBLISHER]

We proposed a multiwavelength fiber optical parametric oscillator (MW-FOPO) based on a tunable Mach-Zehnder interferometer.Multiwavelength lasing of the MW-FOPO with a wavelength spacing of about 0.32 nm in a wavelength regime from 1515 to 1600 nm (for lasing wavelengths with the power that exceeds −60 dBm) is achieved. Wavelength spacing of the MW-FOPO can be continuously tuned and multiwavelength lasing with wavelength spacings of 0.08, 0.16, 0.32 nm are demonstrated. The stability of the MW-FOPO at room temperature is discussed and experimentally demonstrated. We also present the comparison of the output spectra between the MW-FOPO and the multiwavelength Erbium-doped fiber laser. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2405-2408, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27069 [ABSTRACT FROM AUTHOR]

OBJECTIVE--Obesity impairs adiponectin expression, assembly, and secretion, yet the underlying mechanisms remain elusive. The aims of this study were 1) to determine the molecular mechanisms by which obesity impairs adiponectin multimerization and stability, and 2) to determine the potential role of disulfidebond-A oxidoreductase-like protein (DsbA-L), a recently identified adiponectin interactive protein that promotes adiponectin multimerization and stability in obesity-induced endoplasmic reticulum (ER) stress and adiponectin downregulation. RESEARCH DESIGN AND METHODS--Tauroursodeoxycholic acid (TUDCA), a chemical chaperone that alleviates ER stress, was used to study the mechanism underlying obesity-induced adiponectin downregulation in db/db mice, high-fat diet-induced obese mice, and in ER-stressed 3T3-L1 adipocytes. The cellular levels of DsbA-L were altered by RNAi-mediated suppression or adenovirus-mediated overexpression. The protective role of DsbA-L in obesity- and ER stress-induced adiponectin downregulation was characterized. RESULTS--Treating db/db mice and diet-induced obese mice with TUDCA increased the cellular and serum levels of adiponectin. In addition, inducing ER stress is sufficient to downregulate adiponectin levels in 3T3-L1 adipocytes, which could be protected by treating cells with the autophagy inhibitor 3-methyladenine or by overexpression of DsbA-L. CONCLUSIONS--ER stress plays a key role in obesity-induced adiponectin downregulation. In addition, DsbA-L facilitates adiponectin folding and assembly and provides a protective effect against ER stress-mediated adiponectin downregulation in obesity. Diabetes 59:2809-2816, 2010 [ABSTRACT FROM AUTHOR]

To better understand the shear mechanical behaviour, the information value (IV) and the fractal theory (FT) models are employed to determine the shear failure regions of rock joints under the low effective normal stress conditions. First, high density point clouds of rock joints at the initial stage (pre-shearing) were collected, using a laser scanning technology and four topography parameters (slope angle, horizontal orientation, elevation difference and curvature) were produced from point clouds, to represent the mesostructure features. Second, direct shear testing were conducted at the end stage (post-shearing), and shear striae on the rock joints were measured to assess shear failure regions, based on image segmentation. Third, by combining morphological features with experimental observations, correlation analyses are performed, to investigate the influences of topography parameters on shear failure behaviors of rock joints, based on IV and normalized weight W i. Similar findings are observed from the two algorithms, indicating that horizontal orientation has a larger impact on shear failure than the other three parameters. Furthermore, under the low normal loading, the shear failure of rock joints are more likely to occur in regions with a slope angle in the range of 30° to 40°, a horizontal orientation in the range of SE to SW (facing shear direction), an elevation difference in the range of 0.15 to 0.30 mm and a curvature in the range of −1000 to −200 mm−1 and 200 to 1000 mm−1. It is notable that the effect of normal loads level on shear failure regions should not be neglected. Eventually, a model is developed to predict the shear failure regions of rock joint and receiver operating characteristic (ROC) analyses show that shear failure determinations, based on the proposed model, match the actual situation. • Four topography parameters were produced from point clouds to represent the mesostructure features of rock joints. • Image segmentation was used to measure the shear failure regions of rock joints under low normal loads. • The relationships between the mesostructure parameters and shear failure regions were established based on IV and FT models. [ABSTRACT FROM AUTHOR]

Deformation monitoring is a powerful tool to understand the formation mechanism of earth fissure hazards, enabling the engineering and planning efforts to be more effective. To assess the evolution characteristics of the Yangshuli earth fissure hazard more completely, terrestrial laser scanning (TLS), a remote sensing technique which is regarded as one of the most promising surveying technologies in geohazard monitoring, was employed to detect the changes to ground surfaces and buildings in small- and large-scales, respectively. Time-series of high-density point clouds were collected through 5 sequential scans from 2014 to 2017 and then pre-processing was performed to filter the noise data of point clouds. A tiny deformation was observed on both the scarp and the walls, based on the local displacement analysis. The relative height differences between the two sides of the scarp increase slowly from 0.169 m to 0.178 m, while no obvious inclining (the maximum tilt reaches just to 0.0023) happens on the two walls, based on tilt measurement. Meanwhile, global displacement analysis indicates that the overall settlement slowly increases for the ground surface, but the regions in the left side of scarp are characterized by a relatively larger vertical displacement than the right. Furthermore, the comparisons of monitoring results on the same measuring line are discussed in this study and TLS monitoring results have an acceptable consistency with the global positioning system (GPS) measurements. The case study shows that the TLS technique can provide an adequate solution in deformation monitoring of earth fissure hazards, with high effectiveness and applicability. [ABSTRACT FROM AUTHOR]