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[Introduction] With the accelerated evolution of the national energy structure, offshore wind power will enter a period of rapid and stable development. At present, the development of offshore wind power near the shore of many provinces in China is nearly completed, and the offshore wind power is gradually developed to the offshore deep water area and will expand to a large scale. Offshore wind power in deep water areas has higher technical requirements for marine geotechnical investigation, and marine geotechnical investigation vessels and equipment need to be professional. But the number of large scale professional marine geotechnical investigation platforms in China is limited and they mainly serve the national marine resource exploration and scientific research work. They are rarely used for offshore wind power geotechnical investigation and the investigation costs are high. The traditional investigation mode of modified marine engineering (cargo) vessels with conventional drilling equipment is no longer suitable for offshore deep water area, nor for marine investigation operations in the short window period. Therefore, it is necessary to conduct in-depth research on the technology of marine geotechnical investigation platform. [Method] Through the research on the domestic marine geotechnical investigation vessel platform and exploration equipment, a comprehensive comparative analysis was carried out on their applicable water depth, ability to resist wind and wave, operation efficiency and investigation quality. According to the geotechnical investigation characteristics of offshore wind power and the sea condition of its development and utilization, the construction ideas and schemes of offshore geotechnical investigation platform for offshore wind power in deep water areas were proposed. [Result] The investigation practice of several offshore wind power projects has proved that the construction scheme of marine geotechnical investigation platform proposed in this paper can be applied to offshore deep water area operation, and can make full use of the 24-48 hour window period of marine investigation. [Conclusion] The scheme proposed in this paper is reasonable, which can effectively improve investigation efficiency, ensure the investigation progress and reduce investigation costs.

The traditional dynamic capacity-increasing technology of overhead conductors needs to monitor the operation state of conductors (temperature, sag, etc.), and the relevant sensors are usually installed directly on the surface of conductors. The installation cost is high, and the operating maintenance is complicated. In this paper, a non-contact dynamic capacity-increasing method for overhead conductors based on CT is proposed. Firstly, the theory of the non-contact dynamic capacity-increasing method for conductors is introduced, and a cooling testing device is designed according to the theory. Then, the cooling index is defined to represent the cooling capacity of the object, and the corresponding cooling indexes for the conductors and the CT are calculated based on the steady-state thermal balance equation. By establishing a cooling correlation model for the conductors and the CT, the calculation for the dynamic ampacity of the conductors can be obtained. Finally, the cooling conditions of cooling testing device at different ambient temperatures and wind speeds are calculated through the finite element simulation method. Combined with the dynamic capacityincreasing method proposed in this paper, the corresponding ampacity value are obtained, and the effect of capacity increase is analyzed. The results show that the non-contact dynamic capacity-increasing method based on the CT has obvious effect in capacity-increasing compared with the static ampacity.

The present study aimed to investigate the success rate, methods and associated complications of left ventricular lead (LVL) extraction and venous pathway reimplantation in patients with cardiac resynchronization therapy device/defibrillator (CRT/CRTD). A retrospective analysis was performed in the patients who underwent CRT/CRTD extraction and reimplantation at our hospital from January 2012 to October 2018. The methods, patient complications and success rate of extraction and reimplantation of LVL were analyzed. A total of 54 patients underwent CRT/CRTD removal (pacemaker infection, n=51; LVL dysfunction, n=3; CRT/CRTD, 34/20). A total of 54 LVLs were removed (3 active electrodes and 51 passive electrodes). The average implantation duration of the LVL was 53.5 months (range, 1–204 months), whereas the success rate of the LVL extraction was 100% (94% completely removed and 6% clinically removed. A total of 6 patients (11%) were treated only by manual traction, whereas the remaining patients had their LVL successfully removed using extraction tools. In the peri-operative period, one fatality occurred (2%). The highest complication rate of the lead extraction was 2% and no minor complications were observed. A total of 36 patients were reimplanted on the right side, which was successful in 31 cases (success rate, 86.1%), whereas 3 cases were successfully reimplanted on the left side. The total success rate of LVL reimplantation was 87.2%. The procedure of the LVL removal and reimplantation exhibited a high success rate and a lower incidence of complications compared with that in patients with cardiac devices. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy (DCM) is characterized by structural and functional changes in the myocardium. Several studies have revealed that myocardial apoptosis and fibrosis occur during DCM. Studies have also indicated that oxidative stress may be a major factor associated with the development of DCM. Protein kinase C (PKC)β2 has been demonstrated to be activated in diabetic rats, and overexpression of PKCβ2 in the myocardium may result in cardiac hypertrophy and fibrosis. The P66shc adaptor protein, which is mediated by PKCβ, serves an important role in apoptosis during oxidative stress. The aim of the present study was to investigate whether the PKCβ2/P66shc oxidative stress pathway is associated with DCM, and to investigate the role and mechanisms of carvedilol in preserving cardiac function. Experimental diabetic rat models were induced by streptozotocin treatment accompanied by high energy intake. Carvedilol was orally administrated at a dose of 1 or 10 mg/kg/day. Cardiac function was evaluated by serum N-terminal pro-B-type natriuretic peptide level and cardiac ultrasound. Myocardial inflammation, oxidative stress, apoptosis and fibrosis were assessed by histopathological and echocardiographic analyses and tests for oxidative markers. Associated proteins and factors were examined by immunohistochemical and western blot analyses. Rats in the diabetes mellitus group exhibited significantly decreased systolic cardiac function along with elevated expression levels of phosphorylated (p)-PKCβ2, phos-P66shc, caspase-3, malondialdehyde, collagen type I, tumor necrosis factor-α and interleukin-1β, which were accompanied by disorder in metabolic processes. Treatment with carvedilol reversed these changes. Thus, the present results suggest that the PKCβ2/P66shc signaling pathway may be associated with diabetic cardiomyopathy; furthermore, carvedilol, as a novel β-receptor blocker, may protect the myocardium from injury by suppressing the myocardial inflammatory response, fibrosis, P66shc-mediated oxidative stress and subsequent apoptosis in myocardial tissue. Consequently, carvedilol may have potential as a therapy for the treatment of DCM. [ABSTRACT FROM AUTHOR]

The authors synthesized struvite crystals in the presence of Proteus mirabilis/urea and by using ammonium carbonate. The products were characterized by scanning electron microscopy and X-ray diffraction. The results showed that the struvite particles produced with bacteria are larger than those formed without bacteria. The formation mechanism of struvite crystals in bacterial solution is explored, indicating that the bacterial biomolecules may act as templates to induce the nucleation, growth, and aggregation of struvite crystals. This study may help to understand the true role of some common bacteria in the stone formation process, and it is also significant for synthesizing inorganic materials. [ABSTRACT FROM PUBLISHER]

With the increase in electricity demand, the ampacity calculation based on the dynamic thermal rating (DTR) technology is increasingly significant for assessing and improving the power transfer capacity of the existing overhead conductors. However, the DTR models now available present some inadequacies in measurement techniques related to wind speed. Therefore, it is essential to propose a new model instead of wind speed measuring in DTR technology. In this paper, the influence analysis of various weather parameters on the conductor ampacity is carried out by using the real weather data. Based on the analysis, it is confirmed that the impact of wind speed is significant, especially in the case of the low wind speed. Moreover, an equivalent heat transfer (EHT) model for DTR technology is proposed instead of wind speed measuring. For this EHT model, the calculation of conductor ampacity is realized through investigating the correlation of heat losses between the heating aluminum (Al) ball and conductor. Finally, combined with the finite element method (FEM), the EHT model proposed in this paper is verified by the Institute of Electrical and Electronic Engineers (IEEE) standard. The results indicate that the error of the EHT model is less than 6% when employing the steady thermal behavior of the Al ball to calculate the ampacity. The EHT model is useful in the real-time thermal rating of overhead conductors. It can increase the utilization of overhead conductors while also avoiding the limitation of the existing measurement techniques related to wind speed. [ABSTRACT FROM AUTHOR]

Summary Lymphocyte homing to draining lymph nodes is critical for the initiation of immune responses. Secondary lymphoid organs of germ-free mice are underdeveloped. How gut commensal microbes remotely regulate cellularity and volume of secondary lymphoid organs remains unknown. We report here that, driven by commensal fungi, a wave of CD45 + CD103 + RALDH + cells migrates to the peripheral lymph nodes after birth. The arrival of these cells introduces high amounts of retinoic acid, mediates the neonatal to adult addressin switch on endothelial cells, and directs the homing of lymphocytes to both gut-associated lymphoid tissues and peripheral lymph nodes. In adult mice, a small number of these RALDH + cells might serve to maintain the volume of secondary lymphoid organs. Homing deficiency of these cells was associated with lymph node attrition in vitamin-A-deficient mice, suggesting a perpetual dependence on retinoic acid signaling for structural and functional maintenance of peripheral immune organs. [ABSTRACT FROM AUTHOR]

In this study, we investigated the mechanisms through which astrocyte-derived exosomes (AS-Exos) alleviate traumatic brain injury (TBI)-induced neuronal defects in TBI model rats and mice. Treatment with AS-Exos alleviated neurobehavioral deficits, cognitive impairment, and brain edema in TBI rats. AS-Exos also significantly reduced neuronal cell loss and atrophy in the TBI rats. AS-Exos significantly reduced oxidative stress and mitochondrial H 2 O 2 levels by increasing the activity of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) in the hippocampal neurons of TBI rats. TUNEL-staining assays showed that AS-Exos significantly reduced TBI-induced neuronal apoptosis. Mechanistically, AS-Exos ameliorated oxidative stress by activating Nrf2/HO-1 signaling in the hippocampus of TBI rats. In addition, the neuroprotective effects of AS-Exos were abrogated in brain-specific Nrf2-knockout mice subjected to TBI. These findings demonstrate that AS-Exos protects against TBI-induced oxidative stress and neuronal apoptosis by activating Nrf2 signaling in both rat and mouse models.

Sag calculation plays an important role in overhead line design. Since the tensile stress of aluminium conductor steel reinforced (ACSR) is required for the sag calculation, an analysis on sag behaviour when considering the tensile stress distribution can be very useful to improve the accuracy of sag results. First, this paper analyses the ACSR tensile stress distribution arising from the temperature maldistribution through proposing a new calculation formula. A finite-element analysis (FEA) model of ACSR is conducted for the solution of the new formula. By using the results, the error and limitations of the existing sag calculation methods for ACSR are discussed. As the critical point of sag calculation, knee-point temperature is solved iteratively involving the tensile stress maldistribution phenomenon in aluminium wires. Based on this iterative solution, an improved analytical method for the ACSR sag calculation considering the creep effect is presented and also compared with the hybrid sag method. The results show that these two methods are basically coincident without the consideration of creep effect, while there are non-negligible differences between them as the creep strain is involved. Compared with the existing analytical methods, the improved sag calculation method proposed in this paper can be applied in more extensive situations., (© 2021 The Authors.)

Following the removal of cardiovascular implantable electronic devices (CIEDs), reassessment of the need for a new device is vital. Some patients may have exhibited an improvement in rhythm or cardiac function and may thus no longer meet the guideline requirements for reimplantation. However, the long-term outcomes of non-systematic device reimplantation remain unknown. In the present study, it was hypothesized that the implantation of pacing systems in selected patients following lead extraction is safe. In order to confirm this hypothesis, a total of 854 patients (aged between 28 and 82 years) who underwent the removal of a CIED were enrolled in the present study and they were all reassessed to determine whether a new device following lead extraction was necessary. In order to determine which patients would undergo non-systematic device reimplantation, the standard guidelines, the criteria and the wishes of the patient were all taken into consideration. Patients remained device-free unless an adverse clinical event occurred that required reimplantation. The primary study endpoint was the rate of sudden death or reimplantation. Between January, 2014 and December, 2019, 854 consecutive patients underwent pacing system extraction, of whom 210 patients (24.6%) underwent non-systematic device reimplantation following careful reassessment (the non-reimplantation group). Among the 210 patients, 162 (77.1%) were fitted with pacemakers, 26 (12.4%) underwent cardiac resynchronization therapy or cardiac resynchronization therapy-defibrillator and 22 (10.5%) were implanted with a cardioverter-defibrillator. During a mean follow-up period of 40.4 months, 86 patients reached the primary endpoint of the study, including 54 out of 210 patients (25.7%) who experienced an adverse clinical event that required reimplantation and 32 out of 210 patients (15.2%) who experienced sudden death. Reimplantation of a new device was not required in ~25% of the patients. On the whole, the present study demonstrates that following pacing system removal, non-systematic device reimplantation associated with close surveillance is safe for selected patients., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Zheng et al.)

Traumatic brain injury (TBI) is a highly lethal event with a poor prognosis. Recovering residual neuronal function in the intermediate stage of TBI is important for treatment; however, neuroinflammation and neuronal apoptosis impede residual neuronal repair processes. Considering that hyperglycemia influences inflammatory processes and neuronal survival, we examined the effects of high glucose on neuroinflammation and neuronal death during the intermediate phase of TBI. Rat models of type 2 diabetes mellitus and/or TBI were developed and behaviorally assessed. Neurological function and cognitive abilities were impaired in TBI rats and worsened by type 2 diabetes mellitus. Histopathological staining and analyses of serum and hippocampal mRNA and protein levels indicated that neuroinflammation and apoptosis were induced in TBI rats and exacerbated by hyperglycemia. Hyperglycemia inhibited hippocampal mitogen-activated protein kinase kinase 5 (MEK5) phosphorylation in TBI rats. In vitro assays were used to assess inflammatory factor expression, apoptotic protein levels and neuronal survival after MEK5 activation in TBI- and/or high-glucose-treated neurons. MEK5/extracellular signal-regulated kinase 5 (ERK5) pathway activation reduced the inflammation, cleaved caspase-3 expression, Bax/Bcl-2 ratio and apoptosis of TBI neurons, even under high-glucose conditions. Thus, high glucose exacerbated neuroinflammation and apoptosis in the intermediate stage post-TBI by inhibiting the MEK5/ERK5 pathway.

Atherosclerosis is driven by an inflammatory milieu in the walls of artery vessels. Initiated early in life, it progresses to plaque formation and form cell accumulation. A culprit in this cascade is the deposition of cholesterol crystals (CC). The involvement of smaller crystals in the early stage of atherosclerotic changes may be critical to the long-term pathological development. How these small crystals initiate the pro-inflammatory events is under study. We report here an unexpected mechanism that microscopic CC interact with cellular membrane in a phagocytosis-independent manner. The binding of these crystals extracts cholesterol from the cell surface. This process causes a sudden catastrophic rupture of plasma membrane and necrosis of the bound cells independent of any known cell death-inducing pathways, releasing inflammatory agents associated with the necrotic cell death. Our results, therefore, reveal a biophysical aspect of CC in potentially mediating the inflammatory progress in atherosclerosis.

Dendritic cells are targeted by regulatory T (T reg) cells, in a manner that operates as an indirect mode of T cell suppression. In this study, using a combination of single-cell force spectroscopy and structured illumination microscopy, we analyze individual T reg cell-DC interaction events and show that T reg cells exhibit strong intrinsic adhesiveness to DCs. This increased DC adhesion reduces the ability of contacted DCs to engage other antigen-specific cells. We show that this unusually strong LFA-1-dependent adhesiveness of T reg cells is caused in part by their low calpain activities, which normally release integrin-cytoskeleton linkage, and thereby reduce adhesion. Super resolution imaging reveals that such T reg cell adhesion causes sequestration of Fascin-1, an actin-bundling protein essential for immunological synapse formation, and skews Fascin-1-dependent actin polarization in DCs toward the T reg cell adhesion zone. Although it is reversible upon T reg cell disengagement, this sequestration of essential cytoskeletal components causes a lethargic state of DCs, leading to reduced T cell priming. Our results reveal a dynamic cytoskeletal component underlying T reg cell-mediated DC suppression in a contact-dependent manner., (© 2017 Chen et al.)

Bats are important reservoir animals and more than 60 viruses have been identified in bats with many of them highly pathogenic to human. In order to understand the natural background, genetic diversity of bat viruses in China and discover potential viral pathogens, Solexa sequencing based viral metagenomics focusing on bats tissues was established and to analyze the virome of bats collected from Jilin, Yunnan and Hunan province. By Solexa sequencing, 116 442 324 useful reads were obtained and assembled into 4 872 contigs, of which 8.2% (4 002/4 4872) were annotated to 36 viral families, including 19 vertebrate virus families, 6 plant virus families, 4 insect virus families and 4 phages. Further contigs analyses showed that some adenovirus, bocavirus, picobirnavirus, parvovirus contigs sequences were similar with known viruses. However, part of them shared limited identities to these viruses implying the discovery of new viruses. Moreover, PCR validation of adenovirus and bocavirus confirmed the results obtained by viral metagenomics. This study aimed to understand bat virome in China by viral metagenomics and could be helpful to establish effective surveillance on wildlife-associate zoonoses.