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There are rich geothermal resources widely distributed in China. After years of continuous exploration and production, most of the shallow geothermal resources have been explored. At present, the exploration mainly focuses on deep geothermal resources. Among many geophysical exploration methods, seismic survey is the most effective means of geothermal resource exploration and production. The weak seismic reflection signal, low S/N ratio and poor imaging of thermal reservoirs due to their seismic geological conditions restrict the production and utilization of deep geothermal resources. In this paper, we considers based on the analysis of the geophysical characteristics of the thermal reservoir that the shielding effect of the strong wave impedance interface between the thermal reservoir and the caprock, the small reflection coefficient inside the thermal reservoir and the serious absorption and attenuation of seismic waves by high-temperature fluids such as hydrothermal fluids and steam in the thermal reservoirs are the main causes of the weak seismic waves in deep thermal reservoirs and proposes a series of seismic data acquisition technologies based on the high-precision vibroseis low-frequency shooting, high-sensitivity geophones long-spread receiving and small-bin size high-fold technologies. They are applied in the seismic acquisition of hot dry rocks (HDR) in Gonghe Basin, Qinghai and have a very good application effect.

Purpose: To investigate the effect of total flavonoids of Cuscuta chinensis (TFCC) on oxidative stress injury in testis and epididymis, and serum levels of reproductive hormones in an oligoasthenospermia (OAS) mice model. Methods: Thirty male Wistar mice were randomly assigned to three groups of 10 mice each: control group, OAS group and TFCC group. With the exception of control group, OAS was orally induced in the mice with ornidazole. The TFCC group received TFCC. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) were determined. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone were also measured. Results: The levels of ROS and MDA in the testis and epididymis significantly increased in OAS group, when compared to control mice (p < 0.05). However, TFCC administration significantly reduced their levels in these tissues (p < 0.05). In contrast, SOD activity significantly decreased in the testis and epididymis of mice in OAS group, relative to control group, but increased significantly after TFCC exposure (p < 0.05). Serum FSH and LH were markedly elevated in OAS group, but treatment with TFCC significantly reduced the levels of these hormones (p < 0.05). Conclusion: These results suggest that TFCC effectively improves sperm quality and reduces oxidative damage in testis and epididymis of mice with oligoasthenospermia via a mechanism involving the regulation of serum levels of reproductive hormones. Thus, TFCC may be useful in the treatment of oligoasthenospermia.

In order to shorten the data update period and further improve the accuracy, a pre-correction X-ray pulsar navigation algorithm based on asynchronous overlapping observation method is proposed. The asynchronous overlapping observation method partially overlaps the two adjacent observation periods, so that the data update period depends on the minimum pulsar observation period rather than the maximum like the other algorithms. The number of sampling points is also reduced to 2, which will effectively reduce the calculation burden. The proposed pre-correction extended Kalman filter uses observation data of adjacent sampling points to achieve a two-fold correction and makes up for the problem of insufficient observations on some sampling points caused by the observation method. Finally, simulations show that the proposed algorithm reduces the position and velocity errors by 21.55% and 19.13% compared to the EKF based on asynchronous observation method when using three detectors to observe the corresponding pulsars simultaneously. At the same time, the running time of one data update calculation is only 6.6% more than that of the EKF algorithm based on synchronous observation method.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is characterized by chronic pain in pelvic area and lower urinary tract symptoms (LUTS). Previous neuroimaging studies demonstrated that chronic pain was associated with the altered brain activity. However, the pathological mechanisms associated with altered brain control of CP/CPPS are not well-understood. Therefore, we sought to investigate the topological properties of white matter brain networks in patients with CP/CPPS and whether the topological configuration of frontal-parietal control network was disrupted. We collected 19 patients with CP/CPPS and 32 matched healthy controls (HCs). Diffusion tensor imaging data of all participates were used to map the white matter structural networks. Graph theoretical method was applied to investigate the alterations of topological properties of brain network in patients. Moreover, we also investigated whether the alerted brain regions might be correlated with any clinical features of patients by the method of Pearson correlation analysis. Both CP/CPPS patients and HCs exhibited a 'small-world' behavior or economical small-world architecture of the white matter brain networks. In addition, CP/CPPS had a lower global efficiency in the right middle frontal gyrus (orbital part) and a higher global efficiency in the left middle cingulate and paracingulate gyri. CP/CPPS also showed increased local efficiency in the left middle cingulate and paracingulate gyri and paracentral lobule. Moreover, the local efficiency of the left middle cingulate gyrus was positively correlated with the scores of the influence of symptoms on the quality of life. The local efficiency of the left precuneus and right supplementary motor area were positively correlated with the total scores of NIH-CPSI and the scores of pain and discomfort symptoms, respectively. Together, we found that patients with CP/CPPS had alterations of connections within the frontal-parietal control network, which suggested that the altered connectivity involved in the executive control processing procedures might contribute to the pathogenesis of the pelvic pain and LUTS in CP/CPPS. Thus these results provided new insights into the understanding of CP/CPPS.

In this work, a novel simple and sensitive detection method for lysozyme based on the surface plasmon resonance of gold nanoparticles has been developed. The lysozyme aptamer constantly immobilized on the surface of gold nanoparticles via a thiol functional group is the recognition element of lysozyme and a stabilizer of this system. The presence of lysozyme leads to the red-shift of the resonance wavelength of gold nanoparticles in accordance with its concentration. Two factors lead to the red spectral shift of gold nanoparticles, which are the increase of the refractive index in the environment surrounding the gold nanoparticles and the aggregation of gold nanoparticles. A critical point is distinguished from the spectral shift as a function of lysozyme concentration, where the dominant power influencing the red-shift is transferred from the first one to the second one with the increase of lysozyme concentration. The limit of detection for lysozyme in this study is 0.054 nM, with a linear calibration ranging from 0.347 nM to 2.431 nM under the optimal usage conditions of 0.1250 nM thiol-aptamer functionalized gold nanoparticles. Therefore, this thiol-aptamer functionalized gold nanoparticle method provides a selective detection strategy for lysozyme and generates a great promising application.

The clinical outcome of porcine circovirus 3 (PCV3) infection is still controversial. Herein, a novel PCV3 isolate (PCV3-China/DB-1/2017) with the molecular characterization of 24A and 27K in the Cap protein was used to inoculate three-week-old cesarean-derived, colostrum-deprived piglets. The nine PCV3 DB-1 inoculated piglets exhibited no obvious clinical symptoms or macroscopic lesions. PCV3 displayed a broad histotropism, including the heart, liver, spleen, lung, kidney, brain, lymph nodes, and tonsil, and the lungs and lymph nodes contained a higher quantity of viral genomes compared to that of the other organs. From 7 days after PCV3 DB-1 inoculation, the piglets showed obvious IgG antibody responses against PCV3 rCap-VLPs. The cumulative results demonstrated that PCV3 trend to low pathogenicity.

As an important platform compound, 3-hydroxypropionic acid (3-HP) can be used as a substrate to synthesize a variety of biological products with commercial potential. The titer of 3-HP by wild-type bacteria is low, which severely limits the large-scale application and production of 3-HP. By modifying the genes related to the metabolic pathway, engineered bacteria using cheap substrates as carbon sources are constructed, the aim of reducing production cost and increasing output is realized. In this paper, the recent progress in the synthesis of 3-HP by metabolic engineering at home and abroad is reviewed. The advantages and disadvantages of glycerol pathway, malonyl-CoA pathway and beta-alanine pathway for synthesis of 3-HP are also summarized and analyzed, and the future development of 3-HP is prospected.3-羟基丙酸 (3-HP) 作为一种重要的平台化合物，以此为底物能够合成多种具有商业潜质的生物制品。野生菌合成3-HP 产量较低，严重限制3-HP 的大规模应用与生产，通过改造合成代谢通路的相关基因，构建以廉价底物为碳源的工程菌株，实现降低生产成本提高产量的目的。文中将对近年来国内外通过代谢工程合成3-羟基丙酸的研究进展进行概述，并对甘油途径、丙二酸单酰辅酶A 途径、β-丙氨酸等途径合成3-HP 的优缺点进行总结分析，对3-HP 未来发展前景进行展望。.

Background Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a chronic disease with a variety of psychosocial and somatic symptoms. CP/CPPS has substantial health care costs with unclear etiology, which may be caused by psychosocial factors. Moreover, previous studies suggested that cognitive processes played a crucial role in the perception of somatic pain. Therefore, the aim of this meta-analysis was to analyze the psychosocial characteristics in men with CP/CPPS, especially the symptom of pain catastrophizing. Methods Relevant publications were searched in different databases including PubMed, MEDLINE, EMBASE, Google Scholar and the Cochran Library using the search terms of "Chronic prostatitis", "Chronic pelvic pain syndrome", "Psychosocial" and "Catastrophizing". The prevalence of psychological factors and pain catastrophizing in men with CP/CPPS were extracted and calculated. Results Ten studies inclusive of 1,308 patients were included. Analysis of NIH-CPSI scores showed that the severity of CP/CPPS was 23.20 (95% CI: 21.13-25.28). The severity of pain catastrophizing was 13.81 (95% CI: 9.83-17.79) estimated by coping strategies questionnaire (CSQ), while the severity of pain catastrophizing was 24.83 (95% CI: 9.19-40.47) estimated by pain catastrophizing scale (PCS). The prevalence of psychosocial symptom was 0.43 (95% CI: 0.32-0.55), while the prevalence of pain catastrophizing was 0.26 (95% CI: 0.21-0.31). Conclusions The psychological factors and pain catastrophizing in men with CP/CPPS was serious. Furthermore, the prevalence of psychosocial symptom and pain catastrophizing was high. There might be a link between pain catastrophizing and somatic symptoms in CPPS. Thus, further prospective studies are needed to evaluate the importance of psychosocial factors in symptom severity of CP/CPPS.

Introduction Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is characterized by chronic pain in pelvic area and lower urinary tract symptoms (LUTS). Previous neuroimaging studies demonstrated that chronic pain was associated with altered brain activity. However, the pathological mechanisms associated with altered brain control of CP/CPPS is not well understood. Therefore, we sought to investigate the topological properties of white matter brain networks in patients with CP/CPPS and whether the topological configuration of frontal-parietal control network was disrupted. Methods We collected 19 patients with CP/CPPS and 32 matched healthy controls (HCs). Diffusion tensor imaging data of all participates were used to map the white matter structural networks. Graph theoretical method was applied to investigate the alterations of topological properties of brain network in patients. Moreover, the associations between the alerted brain regions of patients and clinical measurements were analysised by using Pearson correlation analyses. Results Both CP/CPPS patients and HCs exhibited a 'small-world' behaviour or economical small-world architecture of the white matter brain networks. In addition, CP/CPPS had a lower global efficiency in the right middle frontal gyrus (orbital part) and a higher global efficiency in the left middle cingulate and paracingulate gyri. CP/CPPS also showed decreased local efficiency in the left middle cingulate and paracingulate gyri and paracentral lobule. Moreover, the local efficiency of the left middle cingulate gyrus was positively correlated with the scores of the influence of symptoms on the quality of life. The local efficiency of the left precuneus and right supplementary motor area were positively correlated with the total scores of NIH-CPSI and the scores of pain and discomfort symptoms, respectively. Conclusion Together, we found that patients with CP/CPPS had alterations of connections within the frontal-parietal control network, which suggested that the altered connectivity involved in the executive control processing procedures might contribute to the pathogenesis of the pelvic pain and LUTS in CP/CPPS. Thus these results providing new insights into the understanding of CP/CPPS.

Supplemental materials

A kind of terahertz amplitude modulation structure has been proposed in this work, which could achieve ~75% modulation depth of transmittance under 10V gate voltage. It is attributed to two side factors, one is making use of metallic metamaterial array which excites terahertz resonance and enhances the interaction between the terahertz wave and graphene. Therefore, the modulation of terahertz transmission could be enhanced. The other factor is adopting polyethylene oxide-based electrolytes, as a kind of high capacitance material to effectively tuned chemical potential of graphene layer which acts as the active material modulating the transmitted energy.

Carbohydrate is an important energy source for human body. Among them, saccharides are the main energy for all living organisms to maintain their life activities, and hold some special physiological activities compared with other nutrients. In consideration of their significance in biological process and structural intricacy, a new precise and reliable technique for their structure identification and discrimination is highly desired. In this work, covalently-modified solid-state nanopores (SSN) have been employed for the detection of polysaccharides with a sample concentration of 5 ng/μL under 150 mV of bias, the experimental findings suggested that polysaccharides have different perforation behavior in chemically-modified nanopores compared with that in bare ones due to specific interactions between polysaccharides and modified inner pore surface, in addition, oligo- and polysaccharides exhibited evident distinct translocation characteristics. The results highlight the applicability of SSN approach for the determination of polysaccharides with high accuracy.

A competitive colorimetric assay has been established to detect chloramphenicol (CAP). It is based on the use of colloidal and electrostatically stabilized aptamer-modified gold nanoparticles (GNPs). The CAP aptamer is modified by a sequence of 5 adenosine groups to anchor it on the surface of GNPs. It can competitively capture two compounds, viz. D-(-)-threo-2-amino-1-(4-nitrophenyl)-1,3-propanediol (CAP-base, with a positive charge) and CAP (which is uncharged). The capture of the positively charged CAP-base triggers the aggregation of modified GNPs in salt-containing solution, and this causes a color change from red to purple. However, in the presence of CAP and CAP-base, the capture of the uncharged CAP weakens this color change by a competing process for capture. Thus, the concentration of CAP is associated with the degree of deaggregation of GNPs and can be quantified by the ratio of absorbances at 620 nm and 520 nm. The assay has a 22 nM limit of detection in acidic solution, and the response is linear in the range of 0.20 to 3.20 μM CAP concentration. This assay was successfully applied to the determination of CAP in spiked environmental water samples. Conceivably, this method has a wide scope in that it may be applied to a wide range of analytes if respective aptamers are available. Graphical abstract Schematic presentation of a competitive non-cross linking deaggregating method for detecting chloramphenicol. The surface charge of polyA-Apt@GNPs and its aggregation degree (purple) are determined by the charge of target. (CAP-base: precursor of CAP; PolyA-Apt@GNPs: 5'-polyA-modified DNA aptamer functionalized gold nanoparticles.).

The response of optical fiber surface plasmon resonance (SPR) sensor to potential is monitored in real time. The potential-induced reflectance of a gold-coated optical fiber SPR probe is dependent on potential step width and ionic strength. Wider potential step and stronger ionic strength are generally able to enhance the reflectance and accelerate the response time. The specifically adsorptive anion Cl− provides a pronounced effect on a potential-dependent SPR probe. The exclusive contact of the SPR probe with anion Cl− could significantly slow down the optical response. The work offers opportunities for optical fiber SPR probes to characterize the electrochemical application.

In this paper, a wavelength selective optical fiber surface plasmon resonance sensor, which provides a flexible detection capability, has been experimentally investigated. The light reflected from the sensor tip in response to flowing water and ethanol are monitored at several single wavelengths. The reflected light transient modulated by flowing solvent has an exponential form, which the change in magnitude and response time are dependent on the monitoring wavelength. Optimal wavelength best suited for measurement was determined by investigating the dynamic response curve. Rather than wavelength and angular interrogation methods commonly used in SPR measurement, this single wavelength monitoring scheme is a low-cost, flexible and reliable method.

Nepal alder (Alnus nepalensis), being an ideal and fast-growing pioneer species to accelerate ecological restoration of the degraded habitats in eastern Himalayas, have received extensive attention. In the present study, colonization characteristics, diversity and cadmium tolerance of dark septate endophytes (DSEs) colonizing the roots of Nepal alders were assessed along environmental gradients in a Pb, Zn, and Cd mine tailing, southwestern China. All Nepal alder roots surveyed were conspicuously colonized by DSEs with 23.1-35.8% colonization intensity. In total, 72 culturable strains of melanized root-associated fungi were isolated from the 45 root samples. Most strains were closely related to well-known DSE fungi, such as fungi belonging to the genera Phialophora, Leptodontidium, Cladosporium, and Exophiala. DSEs from heavily metal-polluted sites showed a higher Cd2+ tolerance in vitro than those from the slightly polluted plots. These findings stressed that DSE was an integral component of the root system of Nepal alder growing in metal-contaminated soils, and it is more feasible to obtain heavy metal (HM) tolerant DSEs from mining areas than from no HM-polluted environments for their potential application in phytoremediation. We concluded with a discussion of further research for addressing the unresolved roles of DSEs in A. nepalensis restoration during the early stage of plant establishment in the freshly metal-exposed mining soils. (C) 2015 Elsevier B.V. All rights reserved.

The geometry dependent reflecting spectrum, resonance wavelength and sensitivity of surface plasmon resonance (SPR)-based tapered fiber optic sensor have been investigated. It is observed that as the tip end diameter decreases, the refractive index sensitivity of proposed sensor monotonically increases. However, the voltage sensitivity increases with the tip end diameter decreasing to a certain value. The relationship between the tip end diameter and refractive index sensitivity, voltage sensitivity present here gives a guideline to use tapered fiber optic SPR sensor targeting specific applications.

The terahertz metamaterial with metallic symmetric square slit ring array is proposed to sensing human cells. The sensitivity of the structure is discussed with the finite element method simulations and the optimized structure parameters are obtained. The cell location analysis is carried out and the calculated result shows that the gaps are the most sensitive places in the structure. With the lithography of hard wafer support, the metamaterial terahertz sensor is fabricated on the thin and flexible polyethylene glycol terephthalate (PET) substrate which is low loss in terahertz waveband. In the sensing experiment, the human renal epithelial cell transfected with adenovirus EIA gene-293t cells are in situ grown on the surface of the fabricated terahertz metamaterial sensor. With the terahertz time domain spectroscopy (THz-TDS), the resonant frequency of the metamaterial shift 18GHz after the 293t cells are grown onto it.

High-purity ZnO nanowire networks were directly synthesized on SiO2/Si substrates via catalyst-free chemical vapor deposition. we grow single-crystal ZnO nanowire networks through the reactive ion etching make a rough SiO2/Si substrate surface, which ZnO nanowire networks can grow in the RIE etched area and do not need any pre-deposited metal catalyst or seed layer. The as-grown ZnO nanowire networks achieved on SiO2/Si substrates have good crystal quality with the hexagonal wurtzite phase containing very less structural defects and transfer-free to fabricate UV photodetector, which showed high performance in photocurrent and response speed. Moreover, the fabrication of UV photodetector method we showed here, which would dramatically lower the complexity of the nanodevice fabrication processes and vigorously promot the application of ZnO nanostructures in nanoelectronics and optoelectronics.

microRNAs (miRNAs) represent a class of noncoding RNA species, believed to be regulating gene expression by binding to complementary sites in the 3'UTRs of target mRNAs. They play important regulatory roles in various metabolic pathways in most eukaryotes. The recent discovery of virus encoded miRNAs suggests that viruses may be using them to regulate host and viral gene expression. Another class of closely related small interfering RNAs (siRNAs) also has been found within the HIV-1 genome and shown to be exerting a limited impact on virus reproduction. Additionally, an additional type of viral noncoding RNAs named small noncoding RNAs (sncRNAs) ranging from a few tens to a few hundred nucleotides in length, has also been identified. sncRNAs have a wide phylogenesis and high levels of expression, suggesting they may play an important roles in different species. Here we discuss the genomic organization, expression, conservation as well as potential function of virally encoded miRNA, siRNA, and sncRNAs.

The moisture content of polyethylene (PE) resin is an important factor to affect the quality of PE pipes used in water, gas and oil transportation. To take advantage of the high sensitivity for water with terahertz radiation, we employed terahertz time-domain spectroscopy (THz-TDS) technology to study the water content in PE master batches. The refractive indexes of samples with varying water contents were determined for frequencies between 0.5 and 1.0 THz. We found the refractive indexes were different among four samples and the trends remained during the repeating measurements in nine days. Those differences in the refractive index might be caused by the water content in PE samples. This method provides a potential nondestructive, fast and contactless process in the analysis of PE moisture content.

The TAU robot presents a new configuration of parallel robots with three degrees of freedom. This robotic configuration is well adapted to perform with a high precision and high stiffness within a large working range compared with a serial robot. It has the advantages of both parallel robots and serial robots. In this paper, the kinematic modeling and error modeling are established with all errors considered using Jacobian matrix method for the robot. Meanwhile, a very effective Jacobian approximation method is introduced to calculate the forward kinematic problem instead of Newton–Raphson method. It denotes that a closed form solution can be obtained instead of a numerical solution. A full size Jacobian matrix is used in carrying out error analysis, error budget, and model parameter estimation and identification. Simulation results indicate that both Jacobian matrix and Jacobian approximation method are correct and with a level of accuracy of micron meters. ADAMS's simulation results are used in verifying the established models.

The ANSI/RIA R15.05‐1‐1990 is an American national industrial robotics standard that covers methods for evaluating the point‐to‐point and static performance of industrial robots. This standard introduces many important concepts for carrying out performance tests. These concepts include standard test plane, standard test path, and working space center point. Eight mistakes and two conflict definitions related to working space center point have been identified and corrected in this paper. Most of the mistakes are definition mistakes related to the base coordinate system, working space center point, standard reference plane, and standard test plane. Mistakes also result from the confusion between the reference plane and the test plane.