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Orthologous proteins of species adapted to different temperatures exhibit differences in stability and function that are interpreted to reflect adaptive variation in structural “flexibility.” However, quantifying flexibility and comparing flexibility across proteins has remained a challenge. To address this issue, we examined temperature effects on cytosolic malate dehydrogenase (cMDH) orthologs from differently thermally adapted congeners of five genera of marine molluscs whose field body temperatures span a range of ∼60 °C. We describe consistent patterns of convergent evolution in adaptation of function [temperature effects on K M of cofactor (NADH)] and structural stability (rate of heat denaturation of activity). To determine how these differences depend on flexibilities of overall structure and of regions known to be important in binding and catalysis, we performed molecular dynamics simulation (MDS) analyses. MDS analyses revealed a significant negative correlation between adaptation temperature and heat-induced increase of backbone atom movements [root mean square deviation (rmsd) of main-chain atoms]. Root mean square fluctuations (RMSFs) of movement by individual amino acid residues varied across the sequence in a qualitatively similar pattern among orthologs. Regions of sequence involved in ligand binding and catalysis—termed mobile regions 1 and 2 (MR1 and MR2), respectively—showed the largest values for RMSF. Heat-induced changes in RMSF values across the sequence and, importantly, in MR1 and MR2 were greatest in cold-adapted species. MDS methods are shown to provide powerful tools for examining adaptation of enzymes by providing a quantitative index of protein flexibility and identifying sequence regions where adaptive change in flexibility occurs.

Remote ischemic preconditioning (IPreC) is an effective strategy to defend against cerebral ischemia/reperfusion (IR) injury; however, its mechanisms remain to be elucidated. The aim of the present study was to investigate the effect of IPreC on brain tissue following cerebral ischemia, as well as the underlying mechanisms. Adult male Sprague-Dawley rats were treated with IPreC for 72 h prior to the induction of transient cerebral ischemia and reperfusion. The results demonstrated that IPreC reduced the area of cerebral infarction in the IR rats by 2,3,5-triphenyl-tetrazolium chloride staining. In addition, cell apoptosis was markedly suppressed by IPreC with an increased expression of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associatd X protein using Terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assay and western blot analysis. IR induced a decrease in the level of superoxide dismutase, and IPreC significantly suppressed increased levels of malondialdehyde, lactate dehydrogenase and nitric oxide. The expression of CD11b and CD18 was markedly inhibited by IpreC unsing flow cytometry. Furthermore, IPreC markedly decreased the release of pro-inflammatory factors interleukin (IL)-6 and IL-1β, and enhanced the level of anti-inflammatory factors (IL-10 and IL-1 receptor antagonist) by ELISA assay. Finally, IPreC reduced the levels of transforming growth factor-β-activated kinase 1, phosphorylated-P65/P65, and tumor necrosis factor-α, indicating that the nuclear factor-κB pathway was involved in IPreC-mediated protection against cerebral ischemia. Taken together, the results suggested that IPreC decreased ischemic brain injury through alleviating free radical injury and the inflammatory response in cerebral IR rats.

Rationale Cervical spondylotic radiculopathy (CSR) is a common sensory, motor, and reflex disorder. Numbness, a common subjective symptom of CSR, lacks objective quantitative indicators and recognized effective treatments, but is also difficult to recover from. We present a case report describing a traditional acupuncture treatment for CSR, utilizing a special acupuncture method and point, namely the Yunmen point. Patient concerns A 40-year-old woman presented with unilateral arm numbness caused by CSR. Diagnoses A diagnosis of CSR was made in the orthopedic department of a local hospital. Interventions We attempted acupuncture at the Yunmen (LU 2) acupoint combined with neck-seven-acupoint under computed tomographic guidance. Outcomes After 10 times treatment sessions, the patient no longer experienced weakness, coldness, or numbness in the affected upper limb. In addition, the stiffness in the neck and shoulders was reduced. On physical examination, the patient's left brachial plexus traction test was negative; reassessment of the CSR-20-point score scale showed a perfect score, and the visual analog scale score was 0. Lessons Our report indicates that acupuncture at the LU 2 acupoint combined with neck-seven-acupoint is effective in treating numbness and coldness of the arm, and other neurological symptoms caused by cervical spondylosis. Moreover, with the appropriate acupuncture technique, the risk of acupuncture at the LU 2 acupoint can be minimized.

Rationale According to the literature reports and clinical studies on alopecia areata (AA) from 2008 to 2018, most clinical treatments have been oral drugs and external ointments. At present, systemic immunosuppressive therapy has been widely used in AA, but there are various side effects such as elevated liver enzymes, gastrointestinal discomfort, poor drug compliance, and repeated illness. We present a case report describing a traditional medicine treatment for AA that uses an ethnic therapy of Zhuang medicine, a kind of Traditional Chinese Medicine, namely, medicated thread moxibustion. Patient concerns A 36-year-old man endured AA after going through a family misfortune. Half a year ago, his father passed away suddenly. Since then, he suffered continuous anguish, alcoholism and hair loss, especially in the past 2 months. A coin-shaped area of hair loss began to appear at the top of his head and gradually expanded to the surrounding region. Diagnoses A diagnosis of AA was made in the dermatology department of a local hospital. Interventions The patient was treated with the medicated thread moxibustion method of Traditional Zhuang Medicine at the Kuihua (special points of Zhuang medicine), Zusanli (ST 36), Xuehai (SP 10), Baihui (DU 20), and Taichong (LR 3) points every other day for 4 weeks. Outcomes The area of hair loss showed slight improvement after 1 week of treatment. Only just a sprinkling of wooly hairs, whose color and thickness were similar to those of fine facial hairs, began to emerge sporadically from the follicles; they could be seen only in a bright light. When the patient saw the obvious curative effect, we continued the treatment for 2 weeks with the patient's consent. Three weeks later, the patchy AA area was covered with small cotton-like hairs of different lengths and uneven colors. Lessons The medicated thread moxibustion method of Zhuang medicine can be an effective alternative treatment in patients with AA.

This study deals with the mortality and related physiological responses of aestivating sea cucumber Apostichopus japonicus to acute salinity decrease. Aestivating and active sea cucumbers were exposed to a decrease in salinity (from 30 to 20 psu) at a rate of 2.5 psu every 6 h, and then maintained at 20 psu for 96 h. The mortality of aestivating sea cucumbers was ~30%, which was significantly higher than that of active sea cucumbers (~10%). This result indicated that sea cucumbers in aestivation were more susceptible to hypo-salinity stress. To elucidate the underlying physiological mechanisms, the osmotic pressure in coelomic fluid and the levels of hsp70 and hsp90 mRNA in aestivating and active sea cucumbers were measured. No significant difference in osmoregulation was observed between the two groups. The osmotic pressure of coelomic fluid in both groups changed with decrease in ambient salinity. There were significant differences in the time course and magnitude of hsp70 and hsp90 expression between the two groups. After exposure to decreased salinity, aestivating sea cucumbers showed a delayed up-regulation of hsp70 and hsp90 expression compared with animals in active state, and these levels decreased rapidly to control values. The expression of hsp70 and hsp90 in aestivating sea cucumbers were significantly lower than those in active sea cucumbers after salinity change. The differences in hsp70 and hsp90 expression between the states may partly explain the higher mortality of sea cucumbers in aestivation when exposed to low salinity.

Two different grinding processes were examined to determine the effect grinding has on the quality of a CWS. A series of slurries was prepared from Australian (Au) and Chinese (YZ) coals. Both types of coal were ground by a Chinese (CUMT) and an Australian (JK) grinding process. The performance tests of the prepared CWS showed that fluidity of all slurries was acceptable. The concentration of the CWS from YZ coal ground by the CUMT grinding process was higher than when the JK grinding process was used. The highest concentration was 70.14% in this case. The concentration of the CWS prepared from Au coal by the JK grinding process was higher than when the CUMT grinding process was used. The highest concentration in this case was 70.97%. These differences are caused by the particle size distribution developed during the different grinding processes.

A series of Pd-CeO2/γ-Al2O3 catalysts which have a different CeO2 loading were prepared by impregnation under microwave irradiation. Based on various characterizations, such as XRD, H2-TPR and CO-TPD, the effect of CeO2 loading on catalytic performance and stability of Pd/γ-Al2O3 were examined for one-step dimethyl ether synthesis from syngas. The results show that there are two completely opposite effect on the CO conversation rate of Pd/γ-Al2O3 catalysts after adding CeO2, namely that it can improve Pd dispersion at a suitable loading, hence the CO conversation rate will increase too. However, the surface area and total pore volume of Pd/γ-Al2O3 catalysts decrease by adding excessive CeO2 and CO conversation rate will also reduce. When the CeO2 loading achieve to 2%, catalysts can have relatively high catalytic stability and activity that the CO conversation rate and DME space-time yield can reach 64.7% and 27.82 mmol·ml-1·h-1, respectively.

A series of Pd/γ-Al2O3 catalysts with different additons of Pd were prepared by impregnation. The effect of calcination condition and Pd loading on catalytic performance of catalysts for one-step dimethyl ether synthesis has been investigated. The physic-chemical performance and structure of Pd/γ-Al2O3 catalysts were characterized by CO-TPD, TGA and nitrogen physisorption. The results show that the dispersion of Pd and the amount of adsorbration on the CO-bridge of Pd could be increased to by the moderate microwave heating on the catalysts, and the catalyst performance can be improved. But a large number of surface acidic sites of Pd/γ-Al2O3 are covered by highly fragmented Pd-grain, it causes DME selectivity reduced. And the excessive Pd can reduce the samples’ surface acid, decrease the dispersion of the metal Pd and block up the pore of γ-Al2O3. The CO conversion rate and DME space-time yield could reach 60.1% and 28.76 mmol·g-1·h-1 respectively at 2% Pd loading, at this time Pd/γ-Al2O3 has a high Pd activity surface and ideal acid sites.

Chinese National Science Foundation [30400333]; National Key Technologies RD Reward Research Foundation for Talented Young and Middle Aged Scientists of Shandong, China [BS2009NY019]

Two coal samples of similar rank were chosen from Australia and China to investigate the differences in Coal–Water Slurry (CWS) made from them. The effect of ash content and particle size gradation on these properties was also studied. Different grinding times were used when grinding the two coals and particle size analysis of these ground coals was used to select samples with a “double-peak” particle size distribution. All the “double-peak” samples were used to prepare a CWS. The concentration, viscosity, fluidity, and stability of each CWS were measured. The results show that the properties of a CWS prepared from a coal sample with a “double-peak” size distribution are better than those CWS prepared from samples with a mono-modal particle distribution. The ash content of Australian coal is 21.72% higher than the ash content of Shenhua coal. The highest coal concentration in slurry from the Australia coal is 11.01% higher than in CWS from the Shenhua coal. The fluidity and stability of the CWS prepared from the Australian coal are both better than the fluidity and stability of slurry prepared from Shenhua coal. High ash content in the Australian coal improves the pulping results of a CWS made from it.

Coal samples in the air for three months were characterized by Thermogravimetric Analysis (TGA). The effect of a PVA oxygen-insulating barrier on the spontaneous combustion of coal was examined. The moisture loss activation energy, oxidation activation energy and combustion activation energy were calculated by an integral method using the Coats-Redfen formula. The results show that the tendency for spontaneous combustion of three coal samples (judged by the activation energy) falls in the order: CYW>YJL>SW. The oxidation activation energy and combustion activation energy of coal protected by the PVA oxygen-insulating barrier increased. A significant increase in the combustion activation energy was noted, especially for the CYW coal where the increase was 28.53 kJ/mol. Hence, oxidation of the protected coal samples was more difficult. The PVA oxygen-insulating barrier helps to prevent spontaneous combustion of the coal.

We studied thermal tolerance limits, heat-hardening, and Hsp70 to elucidate the difference in thermotolerance between two color variants of the sea cucumber Apostichopus japonicus. Green and Red variants occupy different habitats and have different aestivation responses to high temperature in summer. In the absence of heat-hardening, the variants showed no difference in the temperature at which 50% of the individuals died: Green, 31.49 degrees C; Red, 31.39 degrees C. However, Green specimens acquired higher thermotolerance than Red after a prior sublethal heat exposure. After 72 h of recovery from a heat-hardening treatment (30 degrees C for 2 h), the survival of Green variants was more than 50% and that of Red was less than 5% when they were treated at 33 degrees C for 2 h. Levels of mRNA and protein for Hsp70 were significantly higher in Green than Red after the heat shock of 30 degrees C, and the stability of hsp70 mRNA of Green was significantly higher than that of Red. Our findings suggest that within the same species, different variants that have similar thermal limits in the absence of heat-hardening can acquire different thermotolerances after a prior sublethal heat shock. The difference in induced thermotolerance between Green and Red is closely related to the expression pattern of Hsp70, which was partly governed by the stability of hsp70 mRNA.

Thermal history can affect organisms' thermal resistance, however, effects of thermal history on thermal resistance and roles of heat shock protein 70 (Hsp70) in sea cucumber Apostichopus japonicus are not well understood. In the present study, the lethal thermal limits and expressions of Hsp70 of sea cucumbers that were acclimated at different temperatures (22 °C or 12 °C) for 30 days were studied. The upper lethal temperatures (ULTs 50 ) for sea cucumbers acclimated at 22 and 12 °C were 31.8 °C (31.5–32.1 °C) and 30.9 °C (30.6–31.3 °C), respectively. In heat shock experiments, sea cucumbers acclimated at different temperatures (22 °C or 12 °C) were exposed to several high temperatures (25, 27, 29, 31 and 32 °C) for 2 h, followed by 2 h recovery at 17 °C, and the levels of hsp70 were measured using semi-quantitative RT-PCR and western blotting. The maximum induction temperatures for sea cucumbers in 22 °C and 12 °C acclimation treatments were 31 °C and 29 °C, respectively. These results showed that the temperature acclimation could affect sea cucumbers' upper thermal limit, which was related to the changed expression pattern of Hsp70 in the sea cucumber. In practice, sea cucumbers that overwinter in southern China could acquire higher thermal resistance than those reared in the north.

Thermo-gravimetric-analysis (TGA) was used to analyze the combustion characteristics of an oil shale and semi-cokes prepared from it. The effect of prior pyrolysis and TGA heating rate on the combustion process was studied. Prior pyrolysis affects the initial temperature of mass loss and the ignition temperature. The ignition temperature increases as the volatile content of the sample decreases. TG/DTG curves obtained at different heating rates show that heating rate has little effect on ignition temperature. But the peak of combustion shifts to higher temperatures as the heating rate is increased. The Coats-Redfern integration method was employed to find the combustion-reaction kinetic parameters for the burning of oil shale and oil shale semi-coke.

An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we designed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal (13–25 mm) covered with fine coal (0–3 mm). A BP artificial neural network (ANN) with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal — 6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the prediction of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 °C, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles.

This study deals with the effect of thermal and osmotic stress on growth, osmoregulation and Hsp70 level in the sea cucumber Apostichopus japonicus Selenka. Sea cucumbers were exposed to 30 °C (Hs treatment) or 20 °C (control) for 2 h, and then were challenged with osmotic shock, which was administered by transferring the sea cucumbers from natural seawater (about 32 ppt) to different salinities (20 ppt, 25 ppt, 30 ppt, and 40 ppt). After a 30-day experiment, the specific growth rate (SGR) and survival rate of sea cucumbers were measured. To elucidate the underlying physiological mechanisms, osmotic pressure of the coelomic fluid, Na + /K + -ATPase and Hsp70 level of the sea cucumbers from Hs treatment and control were measured at selected times (1 h, 2 h, 6 h, 24 h, and 48 h) after the osmotic shock. At the end of the 30-day experiment, SGR of Hs sea cucumber was higher than that of the control at salinity of 20 ppt. However, SGR of Hs sea cucumber was lower than that of the control at salinity of 30 ppt, 40 ppt and natural seawater. At salinity of 20 ppt, the survival rate of A. japonicus was only 20%. These results indicted that a salinity of 20 ppt exceeded the ecological tolerance for growth in juvenile A. japonicus . A prior heat shock could accelerate growth when the ambient salinity was below the ecological tolerance for growth (salinity of 20 ppt); on the other hand, it could retard growth when the ambient salinity was within the ecological tolerance for growth (salinity of 25 ppt, 30 ppt, 40 ppt and natural seawater). The osmotic pressure of the coelomic fluid changed rapidly and stabilized by 6 h after the osmotic shock. The temporal change pattern of Na + /K + -ATPase activity increased initially and reached the maximum value within 6 h. These results indicated that A. japonicus was an osmotic conformer, and the activity of Na + /K + -ATPase had an adaptive response to the change of ambient salinity. Both thermal and osmotic stresses could induce the up-regulation of Hsp70, which might partly explain the differences in growth of sea cucumbers at different salinities.

Three coal samples of different ranks were used to study the effect of coal blending on the preparation of Coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentration in slurry made from hard-to-pulp coal can be effectively improved and increased by 3%–5% generally. DLT coal (DaLiuTa coal mine) is very poor in slurryability and the stability and rheology of the resulting slurry are not very good. When the amount of easily slurried coal is more than 30%, all properties of the CWS improve and the CWS meets the requirements for use as fuel. Coalification, porosity, surface oxygenic functional groups, zeta potential and grindability have a great effect on the performance of blended coal CWS. This leads to some differences in performance between the slurry made from a single coal and slurry made from blended coal.

Sensitivity to temperature helps determine the success of organisms in all habitats, and is caused by the susceptibility of biochemical processes, including enzyme function, to temperature change. A series of studies using two structurally and catalytically related enzymes, A4-lactate dehydrogenase (A4-LDH) and cytosolic malate dehydrogenase (cMDH) have been especially valuable in determining the functional attributes of enzymes most sensitive to temperature, and identifying amino acid substitutions that lead to changes in those attributes. The results of these efforts indicate that ligand binding affinity and catalytic rate are key targets during temperature adaptation: ligand affinity decreases during cold adaptation to allow more rapid catalysis. Structural changes causing these functional shifts often comprise only a single amino acid substitution in an enzyme subunit containing approximately 330 residues; they occur on the surface of the protein in or near regions of the enzyme that move during catalysis, but not in the active site; and they decrease stability in cold-adapted orthologs by altering intra-molecular hydrogen bonding patterns or interactions with the solvent. Despite these structure–function insights, we currently are unable to predict a priori how a particular substitution alters enzyme function in relation to temperature. A predictive ability of this nature might allow a proteome-wide survey of adaptation to temperature and reveal what fraction of the proteome may need to adapt to temperature changes of the order predicted by global warming models. Approaches employing algorithms that calculate changes in protein stability in response to a mutation have the potential to help predict temperature adaptation in enzymes; however, using examples of temperature-adaptive mutations in A4-LDH and cMDH, we find that the algorithms we tested currently lack the sensitivity to detect the small changes in flexibility that are central to enzyme adaptation to temperature.