241 research outputs found

    LKM: A LDA-Based K

    Get PDF

    Isolated unilateral brachial plexus injury following carbon monoxide intoxication: a case report and literature review

    Get PDF
    Carbon monoxide (CO) is a gas that has no odor or color, making it difficult to detect until exposure leads to coma or death. CO poisoning is one of the most common and deadly poisonings around the world. CO poisoning is a common and often fatal form of poisoning worldwide. A toxic effect of CO is tissue hypoxia, which leads to systemic complications. Additionally, there may be severe neurological symptoms and delayed complications following CO poisoning. However, peripheral neuropathy is relatively rare after CO poisoning. Previously, only one case of unilateral plexopathy after CO poisoning, accompanied by rhabdomyolysis and cognitive dysfunction, has been reported. In this report, an isolated unilateral brachial plexopathy following CO intoxication is described. A key mechanism in this case may be CO-induced spinal cord ischemia. Immediate administration of hyperbaric oxygen therapy (HBOT) is crucial to prevent peripheral neuropathy after acute CO intoxication. Hyperbaric oxygen therapy (HBOT) should be administered immediately after acute CO intoxication to prevent peripheral neuropathy. Additionally, peripheral neuropathy following acute CO intoxication may benefit from consistent rehabilitation training

    Measurement of the complex polar magneto-optical Kerr effect using weak measurement

    Full text link
    Polar magneto-optical Kerr effect (PMOKE) is one of the most widely being applied magneto-optical Kerr effects (MOKE) due to the induced complex MOKE signal, consisting of the Kerr rotation angle and the ellipticity, is very sensitive to the magnetization component perpendicular to the magnetic surface. However, the Kerr rotation angle and the ellipticity invariably coexist and pose a challenge in their separation. This dual presence plays a pivotal role in defining the light intensity detected, ultimately restricting the advancements in the measurement precision. In this paper, we propose a weak measurement (WM) scheme to measure the complex MOKE in the pure polar configuration. Unlike the traditional MOKE or WM method using a quarter-wave-plate to measure the Kerr rotation angle and the ellipticity separately, we realize the simultaneous measurement of these two parameters in a single WM process using two new pointers, which possesses a larger linear response region compared with the previous amplified shift pointer. The measurement precision for the complex PMOKE angle reaches to 10410^{-4} deg in our experiment. Besides, the complex magneto-optical constant Q is also calculated. This work is of great significance for the measurement of the complex PMOKE with high efficiency, ultra-precision, low cost, and is an important attempt to obtain complex physical quantities using WM

    Upwelling velocity and ventilation in the western South China Sea deduced from CFC-12 and SF6 observations

    Get PDF
    This study presents observations of the transient tracers CFC-12 and SF6 in the western South China Sea during the fall of 2015. A CFC-12 maximum was discovered in the western South China Sea at the subsurface layer (150–200 m), which could be traced back to the North Pacific Tropical Water. The transit time distribution approach was used to estimate the ventilation time in this area. The constrained Δ /Γ ratio of 0.5 was obtained using CFC-12/SF6 tracer pair. This ratio is lower than the empirical unit ratio of one as used for previous estimates. Waters in the northern region of the western South China Sea appear younger than waters in the southern region. The water mass corresponding to the salinity minimum has a mean age of ∼67 ± 16 years along the 15º N line (marked by the red dashed rectangle in Fig. 1), which increases to ∼76 ± 18 years along the 10º N line (blue dashed rectangle, Fig. 1). The higher mean ages indicate that the intermediate water was ventilated from the North Pacific, which is far distant from the South China Sea. The column inventory of Cant is ∼31.3 mol C m–2. Upwelling velocities of up to ∼55 × 10–5 m s–1 was computed using the tracer data, indicating that tracer-free water as yet not influenced by human perturbation could be carried to the upper layer by upwelling. Using the transit time distribution derived mean age with transient tracers provides a possible way to determine the ventilation time scale for the study area

    Dimethyl Sulfoxide Damages Mitochondrial Integrity and Membrane Potential in Cultured Astrocytes

    Get PDF
    Dimethyl sulfoxide (DMSO) is a polar organic solvent that is used to dissolve neuroprotective or neurotoxic agents in neuroscience research. However, DMSO itself also has pharmacological and pathological effects on the nervous system. Astrocytes play a central role in maintaining brain homeostasis, but the effect and mechanism of DMSO on astrocytes has not been studied. The present study showed that exposure of astrocyte cultures to 1% DMSO for 24 h did not significantly affect cell survival, but decreased cell viability and glial glutamate transporter expression, and caused mitochondrial swelling, membrane potential impairment and reactive oxygen species production, and subsequent cytochrome c release and caspase-3 activation. DMSO at concentrations of 5% significantly inhibited cell variability and promoted apoptosis of astrocytes, accompanied with more severe mitochondrial damage. These results suggest that mitochondrial impairment is a primary event in DMSO-induced astrocyte toxicity. The potential cytotoxic effects on astrocytes need to be carefully considered during investigating neuroprotective or neurotoxic effects of hydrophobic agents dissolved by DMSO

    Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

    Get PDF
    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): <60%, <15%, and <30%. It demonstrated that thinning operation with 30% intensity can substantially improve soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity

    Enriched oxygen improves age-related cognitive impairment through enhancing autophagy

    Get PDF
    Age-related cognitive impairment represents a significant health concern, with the understanding of its underlying mechanisms and potential interventions being of paramount importance. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) on cognitive function and neuronal integrity in aged (22-month-old) C57BL/6 mice. Male mice were exposed to HBOT for 2 weeks, and spatial learning and memory abilities were assessed using the Morris water maze. We employed transcriptome sequencing and Gene Ontology (GO) term enrichment analysis to examine the effects of HBOT on gene expression profiles, with particular attention given to synapse-related genes. Our data indicated a significant upregulation of postsynapse organization, synapse organization, and axonogenesis GO terms, likely contributing to improved cognitive performance. Moreover, the hyperphosphorylation of tau, a hallmark of many neurodegenerative diseases, was significantly reduced in the HBO-treated group, both in vivo and in vitro. Transmission electron microscopy revealed significant ultrastructural alterations in the hippocampus of the HBOT group, including an increase in the number of synapses and the size of the active zone, a reduction in demyelinated lesions, and a decreased number of “PANTHOS.” Furthermore, Western blot analyses confirmed the upregulation of PSD95, BDNF, and Syn proteins, suggesting enhanced synaptic plasticity and neurotrophic support. Moreover, HBOT increased autophagy, as evidenced by the elevated levels of Beclin-1 and LC3 proteins and the reduced level of p62 protein. Finally, we demonstrated that HBOT activated the AMPK-mTOR signaling pathway, a critical regulator of autophagy. Notably, our findings provide novel insights into the mechanisms by which HBOT ameliorates age-related cognitive impairment, suggesting the potential therapeutic value of this approach

    Association between Single Nucleotide Polymorphisms in SIRT1 and SIRT2 Loci and Growth in Tibetan Sheep

    Get PDF
    Silent information regulator 1 and 2 (SIRT1, 2) were NAD+-dependent histone or non-histone deacetylase, which emerged as key metabolic sensors in several tissues of mammals. In the present study, the search for polymorphisms within the ovine SIRT1 and SIRT2 loci as well as association analyses between SNPs and growth-related traits were performed in Tibetan sheep. To determine the expression pattern of SIRT1 and SIRT2 genes in Tibetan sheep, the quantitative real-time polymerase chain reaction (qPCR) analysis revealed that those two genes were widely expressed in diverse tissues. Expression of SIRT1 was less in abomasum of lamb, whereas it was greater in duodenum within adult stage. In the case of SIRT2, the greatest expression was observed in reticulum (lamb) and in muscle (adult), whereas the least expression was in liver for lamb and in kidney for adult animals. The association analysis demonstrated that g.3148 C \u3e T polymorphism of SIRT1 affected heart girth (p = 0.002). The g.8074 T \u3e A SNP of SIRT2 had a significant correlation with body weight (p = 0.011) and body length (p = 0.008). These findings suggested that the SIRT1 and SIRT2 polymorphism was involved in growth-related traits in Tibetan sheep, which may be considered to be genetic markers for improving the growth traits of Tibetan sheep

    KOH-doped polybenzimidazole membrane for direct hydrazine fuel cell.

    Get PDF
    Alkaline direct hydrazine (N2H4) fuel cells (DHFCs) are considered one of the most promising liquid-fed fuel cells because of their high energy density, high theoretical voltage, and zero carbon dioxide (CO2) emissions. However, the lack of a suitable electrolyte membrane impedes the further development of alkaline DHFC. Herein, a potassium hydroxide (KOH)-doped polybenzimidazole (PBI) membrane is applied in alkaline DHFCs, and the detailed operating conditions are investigated for the first time. With optimal KOH and N2H4 concentrations in the anolyte, membrane thickness, and cathode gas humidity, the DHFC gives a peak power density of 0.708 W cm-2. The results of this study demonstrate the promising application of PBI membranes in DHFC and provide a platform to evaluate the performance of catalysts synthesized for DHFC

    KOH-doped polybenzimidazole membrane for direct hydrazine fuel cell

    Get PDF
    Abstract(#br)Alkaline direct hydrazine (N 2 H 4 ) fuel cells (DHFCs) are considered one of the most promising liquid-fed fuel cells because of their high energy density, high theoretical voltage, and zero carbon dioxide (CO 2 ) emissions. However, the lack of a suitable electrolyte membrane impedes the further development of alkaline DHFC. Herein, a potassium hydroxide (KOH)-doped polybenzimidazole (PBI) membrane is applied in alkaline DHFCs, and the detailed operating conditions are investigated for the first time. With optimal KOH and N 2 H 4 concentrations in the anolyte, membrane thickness, and cathode gas humidity, the DHFC gives a peak power density of 0.708 W cm −2 . The results of this study demonstrate the promising application of PBI membranes in DHFC and provide a platform to evaluate the performance of catalysts synthesized for DHFC
    corecore