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The production of industrial chemicals with renewable biomass feedstock holds potential to aid the world in pursuing a carbon-neutral society. Trimellitic and trimesic acids are important commodity chemicals in industry that are prepared by the oxidation of petroleum-derived trimethylbenzene. To reduce the dependence on the limited oil source, we develop a potential sustainable alternative towards trimellitic and trimesic acids using biomass-based 2-methyl-2,4-pentandiol (MPD), acrylate and crotonaldehyde as starting materials. The process for trimellitic acid includes dehydration/D-A reaction of MPD and acrylate, flow aromatization over Pd/C catalyst, hydrolysis and catalytic aerobic oxidation (60% overall yield). The challenging regioselectivity issue of D-A reaction is tackled by a matched combination of temperature and deep eutectic solvent ChCl/HCO2H. Crotonaldehyde can also participate in the reaction, followed by Pd/C-catalyzed decarbonylation/dehydrogenation and oxidation to provide trimesic acid in 54% overall yield. Life cycle assessment implies that compared to conventional fossil process, our biomass-based routes present a potential in reducing carbon emissions.

Introduction: Anxiety and depressive disorders are highly prevalent mental health conditions worldwide. However, little is known about their specific prevalence in primary care settings. This study aimed to determine the prevalence of depression, and anxiety in the primary care population and identify associated patient characteristics. Method: We conducted a cross-sectional study using stratified sampling by age with a self-administered questionnaire survey in Singapore’s National Healthcare Group Polyclinics from December 2021 to April 2022. A total score of Patient Health Questionnaire-9 (PHQ-9) ≥10 represents clinical depression and a total score of Generalised Anxiety Disorder-7 (GAD-7) ≥10 indicates clinical anxiety. Multivariable logistic regression was used to identify the factors associated with depression and anxiety. Results: A total of 5694 patients were approached and 3505 consented to the study (response rate=61.6%). There was a higher prevalence of coexisting clinical depression and anxiety (DA) (prevalence=5.4%) compared to clinical depression only (3.3%) and clinical anxiety only (1.9%). The odds of having DA were higher among those aged 21–39 years (odds ratio [OR] 13.49; 95% confidence interval [CI] 5.41–33.64) and 40–64 years (OR 2.28; 95% CI 1.03–5.03) compared to those ≥65 years. Women had higher odds of having DA (OR 2.33; 95% CI 1.54–3.50) compared to men. Respondents with diabetes had higher odds of having DA (OR 1.78; 95% CI 1.07–2.94) compared to those without diabetes. Conclusion: Coexisting clinical depression and anxiety are significantly present in the primary care setting, especially among younger individuals, patients with diabetes and women. Mental health screening programmes should include screening for both depression and anxiety, and target these at-risk groups.

Abstract Indan and tetralin are widely used as fuel additives and the intermediates in the manufacture of thermal-stable jet fuel, many chemicals, medicines, and shockproof agents for rubber industry. Herein, we disclose a two-step route to selectively produce 5-methyl-2,3-dihydro-1H-indene (abbreviated as methylindan) and tetralin with xylose or the hemicelluloses from agricultural or forestry waste. Firstly, cyclopentanone (CPO) was selectively formed with ~60% carbon yield by the direct hydrogenolysis of xylose or hemicelluloses on a non-noble bimetallic Cu-La/SBA-15 catalyst. Subsequently, methylindan and tetralin were selectively produced with CPO via a cascade self-aldol condensation/rearrangement/aromatization reaction catalyzed by a commercial H-ZSM-5 zeolite. When we used cyclohexanone (another lignocellulosic cycloketone) in the second step, the main product switched to dimethyltetralin. This work gives insights into the selective production of bicyclic aromatics with lignocellulose.

Woody plant encroachment (WPE), a global phenomenon documented across various biomes and continents, has the potential to significantly impact ecosystem carbon and water cycling. However, the impacts of WPE on carbon and water cycling in wetland ecosystems of middle and high latitudes are still lacking. In this study, the interannual and seasonal impacts of WPE on gross primary production (GPP) and evapotranspiration (ET), as well as their underlying mechanisms, within boreal wetland ecosystems located in middle-high latitude regions, were examined using remote sensing datasets spanning the period 2001–2016. Our results demonstrated that WPE enhanced annual GPP, ET, Normalized Difference Vegetation Index (NDVI), and solar-induced chlorophyll fluorescence (SIF) in boreal wetlands with impacts increasing over time. The multi-year average GPP and ET in fully encroached wetland ecosystems were approximately 31% and 3% higher, respectively, compared to pure wetland ecosystems. Prominent increases in wetland GPP occurred during the early growing season, while an exacerbation of ET was observed during the peak growing season. The impacts of WPE on wetland GPP and ET were predominantly attributed to increased vegetation greenness followed by secondary contributions from climate change. Climate change not only directly influenced the responses of GPP and ET to WPE but also exerted indirect effects by regulating vegetation greenness and the degree of encroachment. Our findings offer valuable insights into the understanding of the interaction between WPE and climate change, highlighting the importance of considering WPE effects and their drivers for accurate predictions of carbon and water cycles, as well as atmosphere–biosphere feedbacks in boreal wetlands.

Summary: Indanone and its analogs are widely used intermediates for many useful chemicals. Decalin and its alkylated analogs are major components of thermal-stable aviation fuels and the additives used to improve the thermal stability of aviation fuel. In this work, we develop an integrated route to selectively produce trimethyl-indanone or alkylated decalin with cellulose. First, cellulose was hydrogenolyzed to 2,5-hexanedione in a biphasic reaction system of toluene/NH4Br aqueous solution over Pd/C catalyst. Under the catalysis of alkali hydroxide, 2,5-hexanedione was converted to a mixture of C12 oxygenates (with trimethyl-indanone as the main component) at room temperature. Trimethyl-indanone can be used as an intermediate for many useful chemicals. Moreover, the C12 oxygenates can be hydrodeoxygenated to a mixture of dimethyl decalin and C12 monocycloalkanes with a low freezing point (200 K) and high density (0.85 g mL−1). This work provides insights on the preparation of indanone or advanced aviation fuel with cellulose. Science for society: The production of valuable chemicals and sustainable aviation fuel (SAF) with renewable, cheap, and abundant lignocellulose has drawn a lot of attention. Indanone and its analogs are widely used as intermediates in the manufacture of many useful chemicals. Currently, these compounds are obtained from fossil resources at low yields. Decalin and alkylated decalins are additives to improve the thermal stability of aviation fuel. Herein, we report an integrated route for the selective preparation of trimethyl-indanone or alkylated decalins with cellulose, the most abundant biomass. Compared with the reported processes to produce indanone analogs or SAF, this new process has several advantages, such as renewable feedstock, mild reaction conditions, fewer steps, and excellent fuel properties (e.g., lower freezing point, higher volumetric heat value, thermal stability of final products, etc.). This work paves a new way for the high-value utilization of cellulose.

Alpine tundra, covering 3% of the Earth’s land surface, harbors approximately 4% of higher plant species. Changes in this vegetation significantly impact biodiversity and ecosystem services. Recent studies have primarily focused on large-scale and long-term vegetation changes in polar and high-latitude regions. However, the study of short-term vegetation changes and their primary drivers has received insufficient attention in alpine tundra. This study aimed to investigate vegetation changes and their dominant drivers in the alpine tundra of Changbai Mountains-located at the southern edge of the alpine tundra distribution in Eastern Eurasia-over a short period by re-surveying permanent plots in 2019 and comparing them with data from 2014. The results showed that significant changes were observed in alpine tundra vegetation during the study period. The importance values of typical alpine tundra plants such as Rhododendron chrysanthum, Vaccinium uliginosum, and Dryas octopetala decreased noticeably, while those of herbaceous species such as Deyeuxia angustifolia and Sanguisorba sitchensis increased significantly. Species richness, diversity, and evenness at different altitudinal gradients showed varying degrees of increase. A distinct expansion trend of herbaceous species was observed in the alpine tundra, contributing to a shift in plant community composition toward herbaceous dominance. This shift might result in the meadowization of the dwarf shrub tundra. Our findings further revealed that soil nutrients rather than climate factors, dominated the changes of plant communities over a short period. These findings provide scientific references for the conservation and management of biodiversity, as well as for projecting future vegetation dynamics in alpine tundra.

In the context of energy transition and carbon neutrality strategies, distributed renewable energy is widely emerging on the distribution side. However, due to the volatility and randomness characteristics of distributed renewable energy, its full absorption poses a huge challenge to the economy and stable operation of the power grid. Flexible resources on the demand side, represented by air conditioners and electric vehicles, can participate in grid dispatching, improving the economic efficiency and reliability of system operation. To this end, this paper proposes an intraday dispatch strategy for demand-side flexible resources based on two-stage optimization. First, based on a generalized energy storage model, the adjustable flexibility of demand-side flexible resources is modeled. Second, to hinder the uncertainties related with markets and demand-side flexible resources, the rolling optimization is adopted for the optimal bidding, thus enabling demand-side flexible resources to participate in the intraday market with low risks of profit losses. Third, based on the bidding decision, real-time dispatch optimization is carried out to cope with the system operation deviation caused by forecast errors. Then, in the real-time control stage, the dispatch instructions are decomposed to the control units to achieve power tracking. Finally, the proposed method is simulated and verified on a test system. The results show that by coordinating the operation of demand-side flexible resources through two-stage optimization, the uncertainties of renewable energy output, market price, etc. Can be effectively overcome, and the economics of system operation can be improved.

Accurate land-sea classification of ATL03 datasets is the prerequisite for signal photons identification and higher-level data production. Current photon classification methods are mainly based on physical models and machine learning methods. Physical models necessitate a priori knowledge of the background noise rate, while machine learning methods require extensive manual intervention, which can be time-consuming. This work introduced a fast feature detection model (FFD model) for land-sea classification that eliminates the need for prior knowledge and is not constrained by time. The land-sea boundary usually experiences significant photon height changes and reflective intensity differences on both sides. The FFD model was developed to efficiently detect the inflection point of photon reflective intensity for preliminary land-sea classification. Minor classification errors were carefully corrected based on topographic geometric distribution in further refinement. The FFD model was applied to three typical land-sea boundary types to evaluate its classification accuracy. Validation of classification results with consistent Sentinel-2 images and manually tagging photons indicated that the FFD method exhibited substantial robustness to various land-sea boundary landforms. The FFD model can process nearly 105 raw photon classifications per second, with an average overall accuracy of 99.42 % for preliminary classification results. Coastal slope and surface reflection in land-sea boundary may have impact on classification accuracy. These effects were carefully eliminated in the refinement process, resulting in an average overall accuracy improvement to 99.86 %. Consequently, the FFD model represented a robust and efficient solution for automatic land-sea classification in coastal shallow water, coral reefs, and estuary areas.

Woody plant encroachment (WPE), a widespread ecological phenomenon globally, has significant impacts on ecosystem structure and functions. However, little is known about how WPE affects phenology in wetland ecosystems of middle and high latitudes. Here, we investigated the regional-scale effects of WPE on the start (SOS), peak (POS), end (EOS), and length (GSL) of the growing season in boreal wetland ecosystems, and their underlying mechanisms, using remote sensing dataset during 2001–2016. Our results showed that WPE advanced the annual SOS and POS, while delaying EOS and extending GSL in boreal wetlands with these impacts increasing over time. When boreal wetland ecosystems were fully encroached by woody plants, the SOS and POS were advanced by 12.17 and 5.65 days, respectively, the EOS was postponed by 2.74 days, and the GSL was extended by 15.21 days. We also found that the impacts of WPE on wetland SOS were predominantly attributed to the increased degree of WPE (α), while climatic factors played a more significant role in controlling the POS and EOS responses to WPE. Climate change not only directly influenced phenological responses of wetlands to WPE but also exerted indirect effects by regulating soil moisture and α. Winter precipitation and spring temperature primarily determined the effects of WPE on SOS, while its impacts on POS were mainly controlled by winter precipitation, summer temperature, and precipitation, and the effects on EOS were mainly determined by winter precipitation, summer temperature, and autumn temperature. Our findings offer new insights into the understanding of the interaction between WPE and wetland ecosystems, emphasizing the significance of considering WPE effects to ensure accurate assessments of phenology changes.

In this paper, triaxial loading and unloading tests under different conditions were carried out to explore the deformation and failure characteristics of hard rock marble, and the acoustic emission information of the test process was monitored synchronously to obtain the acoustic emission distribution characteristics. The test results show that: (1) when the confining pressure unloading rate is low, the rock yielding is more obvious, the damage peak is higher, and the Poisson effect is more obvious under loading and unloading, while when the unloading rate is high, it shows multi-stage damage; (2) there is a linear relationship between strain deviatoric stress flexibility and unloading rate, as the unloading rate accelerates, the circumferential and volumetric flexibility increases and the axial flexibility decreases; (3) the lower the unloading rate, the higher the confining pressure, and the main shear surface of the rock gathers a large number of tensile microcracks to form a shear zone, while the higher the unloading rate, the lower the confining pressure, and the main shear surface is thoroughly penetrated and ruptured; (4) acoustic emission can characterize the damage degree of marble in the process of loading and unloading, when the confining pressure is low, acoustic emission at the peak damage point appears sharp phenomenon, the overall damage increases with the accelerated rate of unloading, when the confining pressure is high, acoustic emission grows progressively, the overall damage decreases with the accelerated rate of unloading, the overall damage of the rock will appear “ pre-peak to post-peak ” hysteresis effect.

Background The posterior ledge (PL) is a vital structure that supports the implant posteriorly during orbital floor reconstruction. This study describes a technique for mapping the PL in relation to the infraorbital margin (IM) in patients with orbital floor blowout fractures. This study establishes the location of the optic foramen in relation to the PL.

Enhancing the alkalinity of the ocean is a promising approach for CO2 removal by promoting marine carbon sequestration. Olivine is a key candidate material for enhancing alkalinity owing to its release of silicates when dissolved in seawater. These released compounds serve as crucial nutrients for phytoplankton such as diatoms to foster their growth, which in turn accelerates olivine dissolution and further enhances carbon sequestration. In this study, we investigated the short-term synergistic CO2 removal effects of an olivine–diatom coculture system. Over a 6-day incubation period, the olivine dissolution was 92% to 144% higher in the olivine–diatom groups compared with the olivine-only groups. The olivine-only groups achieved a CO2 removal efficiency of 5.15% to 5.49%, while the olivine–diatom groups achieved a CO2 removal efficiency of 8.84% to 14.44%. Adding olivine was found to increase the total alkalinity by 70 to 100 μM and the diatom abundance by 26.4% to 58.4%. Diatom growth and the fixed carbon content were greatly enhanced, particularly during the later silicate-depleted stage when the Si:C ratio significantly exceeded that of groups without olivine. This mutually beneficial olivine–diatom coculture system offers a highly efficient CO2 removal strategy for addressing climate change. The results of this study contribute to our understanding of carbonate and biological carbon pump processes.

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline ecotone. The aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species, Picea jezoensis, and the carbon allocation strategies of the species on Changbai Mountain. We employed the 13C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions (tree species at its upper elevation limit (TSAUE, 1,700 ​m a.s.l.) under treeline ecotone; tree species at a lower elevation position (TSALE, 1,400 ​m a.s.l.). We analyzed 13C and the non-structural carbohydrate (NSC) concentrations in various tissues following labeling. Our findings revealed a significant shift in carbon allocation in TSAUE compared to TSALE. There was a pronounced increase in δ13C allocation to belowground components (roots, soil, soil respiration) in TSAUE compared to TSALE. Furthermore, the C flow rate within the plant-soil-atmosphere system was faster, and the C residence time in the plant was shorter in TSAUE. The trends indicate enhanced C sink activity in belowground tissues in TSAUE, with newly assimilated C being preferentially directed there, suggesting a more conservative C allocation strategy by P. jezoensis at higher elevations under harsher environments. Such a strategy, prioritizing C storage in roots, likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season, leading to reduced growth of TSAUE compared to TSALE. The results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees, and enhances our understanding of how non-treeline species might respond to ongoing climate change.

Alpine treeline ecotones are highly sensitive to climate warming. The low temperature-determined alpine treeline is expected to shift upwards in response to global warming. However, little is known about how temperature interacts with other important factors to influence the distribution range of tree species within and beyond the alpine treeline ecotone. Hence, we used a GF-2 satellite image, along with bioclimatic and topographic variables, to develop an ensemble suitable habitat model based on the species distribution modeling algorithms in Biomod2. We investigated the distribution of suitable habitats for B. ermanii under three climate change scenarios (i.e., low (SSP126), moderate (SSP370) and extreme (SSP585) future emission trajectories) between two consecutive time periods (i.e., current–2055, and 2055–2085). By 2055, the potential distribution range of B. ermanii will expand under all three climate scenarios. The medium and high suitable areas will decline under SSP370 and SSP585 scenarios from 2055 to 2085. Moreover, under the three climate scenarios, the uppermost altitudes of low suitable habitat will rise to 2,329 ​m a.s.l., while the altitudes of medium and high suitable habitats will fall to 2,201 and 2,051 ​m a.s.l. by 2085, respectively. Warming promotes the expansion of B. ermanii distribution range in Changbai Mountain, and this expansion will be modified by precipitation as climate warming continues. This interaction between temperature and precipitation plays a significant role in shaping the potential distribution range of B. ermanii in the alpine treeline ecotone. This study reveals the link between environmental factors, habitat distribution, and species distribution in the alpine treeline ecotone, providing valuable insights into the impacts of climate change on high-elevation vegetation, and contributing to mountain biodiversity conservation and sustainable development.

Abstract Analyses of several databases showed that the lncRNA RNF157 Antisense RNA 1 (RNF157-AS1) is overexpressed in epithelial ovarian cancer (EOC) tissues. In our study, suppressing RNF157-AS1 strikingly reduced the proliferation, invasion, and migration of EOC cells compared with control cells, while overexpressing RNF157-AS1 greatly increased these effects. By RNA pulldown assays, RNA binding protein immunoprecipitation (RIP) assays, and mass spectrometry, RNF157-AS1 was further found to be able to bind to the HMGA1 and EZH2 proteins. Chromatin immunoprecipitation (ChIP) assays showed that RNF157-AS1 and HMGA1 bound to the ULK1 promoter and prevented the expression of ULK1. Additionally, RNF157-AS1 interacted with EZH2 to bind to the DIRAS3 promoter and diminish DIRAS3 expression. ULK1 and DIRAS3 were found to be essential for autophagy. Combination autophagy inhibitor and RNF157-AS1 overexpression or knockdown, a change in the LC3 II/I ratio was found using immunofluorescence (IF) staining and western blot (WB) analysis. The autophagy level also was confirmed by autophagy/cytotoxicity dual staining. However, the majority of advanced EOC patients require platinum-based chemotherapy, since autophagy is a cellular catabolic response to cell stress. As a result, RNF157-AS1 increased EOC cell sensitivity to chemotherapy and death under cis-platinum (DDP) treatment by suppressing autophagy, as confirmed by cell count Kit-8 (CCK8) assays, flow cytometry, and autophagy/cytotoxicity dual staining. Therefore, the OS and PPS times were longer in EOC patients with elevated RNF157-AS1 expression. RNF157-AS1-mediated autophagy has potential clinical significance in DDP chemotherapy for EOC patients.

Abstract Experimental vaccines for the deadly zoonotic Nipah (NiV), Hendra (HeV), and Ebola (EBOV) viruses have focused on targeting individual viruses, although their geographical and bat reservoir host overlaps warrant creation of multivalent vaccines. Here we explored whether replication-incompetent pseudotyped vesicular stomatitis virus (VSV) virions or NiV-based virus-like particles (VLPs) were suitable multivalent vaccine platforms by co-incorporating multiple surface glycoproteins from NiV, HeV, and EBOV onto these virions. We then enhanced the vaccines’ thermotolerance using carbohydrates to enhance applicability in global regions that lack cold-chain infrastructure. Excitingly, in a Syrian hamster model of disease, the VSV multivalent vaccine elicited safe, strong, and protective neutralizing antibody responses against challenge with NiV, HeV, or EBOV. Our study provides proof-of-principle evidence that replication-incompetent multivalent viral particle vaccines are sufficient to provide protection against multiple zoonotic deadly viruses with high pandemic potential.

Laparoscopic cholecystectomy is used to treat cholecystitis and cholelithiasis. Because the high risk of the surgery prevents novice doctors from practicing it on real patients, VR-based surgical simulation has been developed to simulate surgical procedures to train surgeons without patients, cadavers, or animals. In this study, we propose a real-time system designed to provide plausible visual and tactile simulation of the main surgical procedures. To achieve this, the physical properties of organs are modeled by particles, and cluster-based shape matching is used to simulate soft deformation. The haptic interaction between tools and soft tissue is modeled as a collision between a capsule and particles. Constraint-based haptic rendering is used to generate feedback force and the non-penetrating position of the virtual tool. The proposed system can simulate the major steps of laparoscopic cholecystectomy, such as the anatomy of Calot’s triangle, clipping of the cystic duct and biliary artery, disjunction of the cystic duct and biliary artery, and separation of the gallbladder bed. The experimental results show that haptic rendering can be performed at a high frequency (> 900 Hz), whereas mesh skinning and graphics rendering can be performed at 60 frames per second (fps).

Real-time monitoring and accurate prediction of toxic gas concentration in the future are of great significance for emergency capability assessment and rescue work. At present, the method of gas concentration prediction based on artificial intelligence still has problems of low accuracy, slow convergence speed and equal feature importance. This paper proposes a feature-aware LSTM model to predict pollutant gas concentration. First of all, we design a set of multi-component toxic gas monitoring equipment that applies in pollution environment, which can at the same time monitor CO, NO2, NH3, HCN, H2S and SO2, six common pollutants; To accurate estimate the toxic gas concentration, we combine the collected the gas data and the environmental parameters and regard them as the input features, and then we obtain toxic gas data based on the sampling policy and the environmental data as our data-set. Finally, we train a FA-LSTM gas concentration prediction model on these data-set. We test the proposed model and compared with ARIMA, ETS and BP network on the same test set. Experimental results show that the proposed model outperforms traditional concentration prediction model. Also, it is better than other state-of-the-art models in predicting accuracy.

Abstract Failure tests on marble during unloading confining-pressure under constant axial stress and simulations with the particle flow code were performed. The influence mechanism of the unloading rate of the confining pressure, initial unloading stress, and confining pressure on the failure characteristics of, and crack propagation in, marble was studied. By using the trial-and-error method, the conversion relationship between the unloading rates of confining pressures in laboratory tests and numerical simulations was ascertained. Micro-cracks formed in the unloading process of confining pressure are dominated by tension cracks, accompanied by shear cracks. The propagation of shear cracks lags that of tension cracks. As the confining pressure is increased, more cracks occur upon failure of the samples. The proportion of shear cracks increases while that of tension cracks decreases. The failure mode of samples undergoes a transition from shear-dominated failure to conjugated shear failure.

Rapid urbanization has brought a range of urban environmental problems that could be harmful to human thermal comfort and health. Urban parks can improve outdoor thermal comfort significantly because of its cooling island effect. However, outdoor thermal comfort is difficult to predict because of its complex nature and there was rare research focused on human physiological thermal responses in different green spaces of urban parks. In this study, thermal comfort of 52 participants were evaluated based on questionnaire survey and physiological parameters measurements including skin temperature (SKT), oxygen saturation (SaO2), heart rate (HR), heart rate variability (HRV) under different green spaces in parks, simultaneously with microclimate measurements. According to the regression analysis, physiological parameters were found having high accuracy in predicting human outdoor thermal comfort, with R2 were 0.803 for SKT, 0.830 for HRV, 0.767 for HR, 0.711 for SaO2 respectively. Results demonstrated that these four physiological parameters were sensitive to microclimate changes and human outdoor comfort thermal state can be captured by monitoring them with reasonable accuracy. This research can provide reference to evaluate outdoor thermal comfort by incorporating the physiological parameters, which can also provide a design basis for creating thermal comfortable outdoor spaces in urban parks.

Synthesis of methylcyclopentadiene (MCPD) with abundant biomass is appealing. Here the authors show that cellulose-derived 3-methylcyclopent-2-enone can be directly hydrodeoxygenated to MCPD over a partially reduced Zn-Mo oxide catalyst.

Abstract Background Depression is characterized by significant and low mood. Classical antidepressants are still not adequate in treating depression because of undesirable side effects. Folic acid, a member of the vitamin B complex, in considered to be strongly associated with the function and development of the central nervous system. Thus, in this study, we established a model of depression through chronic unpredictable mild stress (CUMS) in rats and assessed the antidepressant effects and mechanisms of folic acid. Methods Sprague–Dawley rats were randomly divided into four groups: control, chronic unpredictable mild stress (CUMS), CUMS treated with folic acid, and CUMS treated with citalopram. Rats were assessed in terms of weight change, open-field test and sucrose preference. Homocysteine, monoamine neurotransmitters, interleukin-6, brain-derived neurotrophic factor (BDNF), β-endorphin levels in the serum and brains of rats were analysed. Results Folic acid exhibited antidepressant-like effects in open-field and sucrose preference tests. Folic acid treatment effectively increased the levels of monoamine neurotransmitters, BDNF and β-endorphin, interleukin-6 and homocysteine levels were also significantly suppressed by folic acid administration. Conclusions These findings serve as preclinical evidence that folic acid plays an antidepressant-like role in several pathways involving monoamine neurotransmitters. Thus, folic acid may be used as a potential antidepressant.

Resource resorption from senescing leaves is an important strategy for internal nutrient recycling in plants. However, our understanding of whether the responses of resource remobilization to mire types (fens vs. bogs) differ among various plant growth forms remains unclear. We thus assessed resource remobilization among various growth forms in fens and bogs in the Hani peatland in the Changbai Mountains, northeastern China. We analyzed and compared the concentrations of non-structural carbohydrates (NSCs), nitrogen (N), phosphorus (P), and potassium (K) in leaves and roots collected in August (mid-season) and September (end-season), and calculated the resource remobilization efficiency (RRE) of four species belonging to four growth forms grown in both fens and bogs. The deciduous dwarf trees (Betula fruticosa) and perennial grass (Phragmites australis) had relative higher leaf RRE than the moss (Sphagnum magellanicum). Although leaf nutrient RRE did not differ between fens and bogs, the deciduous dwarf trees had a higher leaf NSC RRE in bogs than in fens, and the moss NSC RRE was lower in bogs than in fens. Our results suggest that reallocation of mobile carbohydrates seems to be more sensitive to the growth condition than nutrients (N, P, and K) under nutrient-poor inhabits, which may be one of the reasons leading to nutrient limitation in peatlands.

Constrained by the characteristics of neutral sections (NS) and traditional vacuum circuit breakers, previous phase-controlled strategies have a long power supply dead time, it is difficult to realize a continuous power supply to the auxiliary power system. The dead time can be reduced by using the ground automatic convert method, hybrid phase-controlled technologies can in theory completely eliminate inrush currents. In this paper, a new system based on hybrid phase-controlled switches is described and termed ground-switching passing neutral section system (GPNSS). The principle for restraining inrush currents is analyzed and strategies are carried out with the dead time limited to 5 ms. The characteristics of the vacuum circuit breaker are illustrated and the closing time window of the transformer is quantified. Through the use of mechanical switches and power electronics, the auxiliary power system may be continuously powered. The prototype system is implemented and experimentally tested in the laboratory.

Positron emission tomography (PET) is becoming an important tool for the investigation of emerging infectious diseases in animal models. Usually, PET imaging is performed after intravenous (IV) radiotracer administration. However, IV injections are difficult to perform in some small animals, such as golden hamsters. This challenge is particularly evident in longitudinal imaging studies, and even more so in maximum containment settings used to study high-consequence pathogens. We propose the use of intramuscular (IM) administration of 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) for PET imaging of hamsters in a biosafety level 4 (BSL-4) laboratory setting. After [18F]F-FDG administration via IM or IV (through surgically implanted vascular access ports), eight hamsters underwent static or dynamic PET scans. Time–activity curves (TACs) and standardized uptake values (SUVs) in major regions of interest (ROIs) were used to compare the two injection routes. Immediately after injection, TACs differed between the two routes. At 60 min post-injection, [18F]F-FDG activity for both routes reached a plateau in most ROIs except the brain, with higher accumulation in the liver, lungs, brain, and nasal cavities observed in the IM group. IM delivery of [18F]F-FDG is an easy, safe, and reliable alternative for longitudinal PET imaging of hamsters in a BSL-4 laboratory setting.

In recent years, fiber-reinforced plastic (FRP) has been widely used in the reinforcement of concrete structure fields due to its favorable properties such as high strength, low weight, easy handling and application, and immunity to corrosion, and the reinforcing effects with FRP grids on tunnel linings should be quantitatively evaluated when the tunnels encounter an earthquake. The aim of the present study is to estimate the reinforcing effects of fiber-reinforced plastic (FRP) grids embedded in Polymer Cement Mortar (PCM) shotcrete (FRP-PCM method) on tunnel linings under the dynamic load. A series of numerical simulations were performed to analyze the reinforcing effects of FRP-PCM method quantitatively, taking into account the impacts of tunnel construction method and cavity location. The results showed that the failure region on lining concrete is improved obviously when the type CII ground is encountered, regardless the influences of construction method and cavity location. With the increment of ground class from CII to DII, the axial stress reduction rate Rσ increases from 13.18% to 48.60% for tunnels constructed by the NATM, while for those tunnels constructed by the NATM, Rσ merely varies from 0.72% to 2.11%. Rσ decreases from 43.35% to 34.80% when a cavity exists on the shoulder of lining, while decreasing from 14.7% to 0.12% when a cavity exists on the crown of lining concrete. All those conclusions could provide valuable guidance for the reinforcing of underground structures.

Endolysins are enzymes used by bacteriophages to cleave the host cell wall in the final stages of the lytic cycle. As such, they are considered promising antibacterial agents for controlling and combating multidrug-resistant (MDR) bacteria. However, the application of endolysins targeting Gram-negative bacteria is greatly hindered by the outer membrane on these bacteria. Lysqdvp001, an endolysin with modular structure, has been reported as one of the most efficient endolysins against the Gram-negative bacterium Vibrio parahaemolyticus. In this study, Plychap001, the truncated recombinant catalytic domain of Lysqdvp001, was demonstrated to exhibit a direct and efficient bactericidal activity against broad spectrum of V. parahaemolyticus strains. Plychap001 was shown to be highly stable and retain high bactericidal activity at high temperatures, over a wide pH range, and at high NaCl concentrations. Plychap001 also exhibited a synergistic lytic effect with EDTA. Additionally, Plychap001 was found to efficiently degrade and eliminate V. parahaemolyticus biofilms on polystyrene surfaces. Our study establishes Plychap001 as a promising method for controlling V. parahaemolyticus in the food industry.

With the acceleration of urbanization throughout the world, climate problems related to climate change including urban heat islands and global warming have become challenges to urban human settlements. Numerous studies have shown that greenways are beneficial to urban climate improvement and can provide leisure places for people. Taking the coastal greenway in Qingdao as the research object, mobile measurements of the microclimate of the greenway were conducted in order to put forward an evaluation method for the research of outdoor thermal comfort. The results showed that different vegetation coverage affected the PET (physiologically equivalent temperature), UTCI (Universal Thermal Climate Index) as well as thermal comfort voting. We found no significant correlation between activities, age, gender, and thermal comfort voting. Air temperature sensation and solar radiation sensation were the primary factors affecting the thermal comfort voting of all sections. Otherwise, within some sections, wind sensation and humidity sensation were correlated with thermal sensation voting and thermal comfort voting, respectively. Both PET and UTCI were found to have a negative correlation with the vegetation coverage on both sides of the greenway. However, the vegetation coverage had positive correlation (R = 0.072) for thermal sensation and significant positive correlation (R = 0.077*) for thermal comfort. The paved area cover was found to have a positive correlation with PET and UTCI, while having a negative correlation with thermal sensation (R = −0.049) and thermal comfort (R = −0.041). This study can provide scientific recommendations for the planning and design of greenway landscapes to improve thermal comfort.

Motor skill learning of dental implantation surgery is difficult for novices because it involves fine manipulation of different dental tools to fulfill a strictly pre-defined procedure. Haptics-enabled virtual reality training systems provide a promising tool for surgical skill learning. In this paper, we introduce a haptic rendering algorithm for simulating diverse tool-tissue contact constraints during dental implantation. Motion forms of an implant tool can be summarized as the high degree of freedom (H-DoF) motion and the low degree of freedom (L-DoF) motion. During the H-DoF state, the tool can move freely on bone surface and in free space with 6 DoF. While during the L-DoF state, the motion degrees are restrained due to the constraints imposed by the implant bed. We propose a state switching framework to simplify the simulation workload by rendering the H-DoF motion state and the L-DoF motion state separately, and seamless switch between the two states by defining an implant criteria as the switching judgment. We also propose the virtual constraint method to render the L-DoF motion, which are different from ordinary drilling procedures as the tools should obey different axial constraint forms including sliding, drilling, screwing and perforating. The virtual constraint method shows efficiency and accuracy in adapting to different kinds of constraint forms, and consists of three core steps, including defining the movement axis, projecting the configuration difference, and deriving the movement control ratio. The H-DoF motion on bone surface and in free space is simulated through the previously proposed virtual coupling method. Experimental results illustrated that the proposed method could simulate the 16 different phases of the complete implant procedures of the Straumann® Bone Level(BL) Implants Φ4.8–L12 mm. According to the output force curve, different contact constraints could be rendered with steady and continuous output force during the operation procedures.

The excavation of deep tunnel in rock mass undergoes complex loading and unloading stress paths, resulting in rib spalling, flaking, and even severe rockburst disasters. Based on the variation law of the stress path of the surrounding rock, laboratory tests of rock mechanics are designed, and the deformation and strength behavior of marble with different initial confining pressure and unloading rates are systematically studied. By introducing strain increment, the characteristic stress, and the dilatancy index, the rock’s dilatancy and brittleness under different unloading conditions are quantitatively analyzed. During unloading, the energy transformation mechanism of rock is described, and the law of deformation and failure is discussed based on characteristic energy. The rock failure strength fitting formula is given by applying the Mogi–Coulomb criterion and elastic strain energy criterion. The advantages of the elastic strain energy criterion are theoretically explained. This study shows that comprehensive consideration of the complex stress paths, confining pressure levels, and the loading-unloading rates of surrounding rock is an effective way to accurately study unloading rock characteristics. The results can provide theoretical basis for stability analysis of high-stress underground engineering.

Background/Aims: The purpose of our experiments was to investigate the targeting relationship of linc00515, miR-140-5p and ATG14 and to explore the roles of linc00515, miR-140-5p and ATG14 in autophagy and chemoresistance of melphalan-resistant multiple myeloma cells. Methods: Plasmids that could interfere with the expression of linc00515 and ATG14 were loaded into myeloma cells, which were cultured with melphalan. MTT assay and flow cytometry analysis were utilized to investigate the effect of linc00515, miR-140-5p and ATG14 on the resistance of myeloma cells. QRT-PCR was used to determine the levels of mRNAs. Western blot was utilized to explore the level of ATG14 and autophagy-related proteins. Dual luciferase assay was utilized to explore the targeting relationship between linc00515, miR-140-5p and ATG14. GFP LC3 fluorescence assay was conducted to study the autophagy of cells. Results: The expression of linc00515 and ATG14 were significantly higher in melphalan-resistant myeloma cells. Knockdown of linc00515 and ATG14 led to decreased autophagy and chemoresistance of melphalan-resistant myeloma cells. The forced expression of miR-140-5p suppressed autophagy and chemoresistance of melphalan-resistant myeloma cells. Conclusion: Linc00515 enhanced autophagy and chemoresistance of melphalan-resistant myeloma by directly inhibiting miR-140-5p, which elevated ATG14 level.

Nipah virus: Virus-like particles protect against major public health concern A vaccine candidate consisting of virus-like particles could offer the first effective prophylaxis against the deadly Nipah virus. Endemic to Malaysia, Bangladesh, and India, Nipah virus is contracted from infected fruit bats and causes severe inflammation of the brain. Pramila Walpita, of the University of Hawaii, working with colleagues at the United States’ National Institute of Allergy and Infectious Diseases, developed an effective vaccine of immunity-generating Nipah virus surface proteins without the virus’ disease-causing genetic material. Their vaccine elicited a significant protective antibody response, with 100% of vaccinated animals surviving subsequent Nipah virus infection. Despite its prevalence and lethality, Nipah virus has no licensed vaccine and poses a serious problem to the developing countries it affects. Walpita’s vaccine candidate could offer a much-needed treatment option and warrants further investigation and pre-clinical trials.

The ability to appropriately mimic human disease is critical for using animal models as a tool for understanding virus pathogenesis. In the case of Nipah virus (NiV), infection of humans appears to occur either through inhalation, contact with or consumption of infected material. In two of these circumstances, respiratory or sinusoidal exposure represents a likely route of infection. In this study, intermediate-size aerosol particles (~7 μm) of NiV-Malaysia were used to mimic potential routes of exposure by focusing viral deposition in the upper respiratory tract. Our previous report showed this route of exposure extended the disease course and a single animal survived the infection. Here, analysis of the peripheral immune response found minimal evidence of systemic inflammation and depletion of B cells during acute disease. However, the animal that survived infection developed an early IgM response with rapid development of neutralizing antibodies that likely afforded protection. The increase in NiV-specific antibodies correlated with an expansion of the B cell population in the survivor. Cell-mediated immunity was not clearly apparent in animals that succumbed during the acute phase of disease. However, CD4+ and CD8+ effector memory cells increased in the survivor with correlating increases in cytokines and chemokines associated with cell-mediated immunity. Interestingly, kinetic changes of the CD4+ and CD8bright T cell populations over the course of acute disease were opposite from animals that succumbed to infection. In addition, increases in NK cells and basophils during convalescence of the surviving animal were also evident, with viral antigen found in NK cells. These data suggest that a systemic inflammatory response and "cytokine storm" are not major contributors to NiV-Malaysia pathogenesis in the AGM model using this exposure route. Further, these data demonstrate that regulation of cell-mediated immunity, in addition to rapid production of NiV specific antibodies, may be critical for surviving NiV infection.

In the complex port environment, ship berthing manipulation is one of the most difficult operations. In this study, an algorithm of berthing and maneuvering was designed for a catamaran unmanned surface vehicle (USV), which is used for port patrol and protection. Considering the influence of wind, waves, and currents, the mathematical model of the maneuvering movement for the twin-hull and twin-propeller USV was established. Based on the Visual Studio development platform, the USV’s berthing manipulation simulation software was designed. Through the turning simulation experiment of the catamaran USV under different differential rotation speeds of the twin propellers, the relationship between the ship’s turning radius and the propeller speed difference was obtained. A simulation experiment of decelerating and stopping ships at different speeds was carried out, which can provide a reference for speed control when berthing. A berthing maneuvering algorithm based on ship maneuverability was proposed. USV’s berthing algorithm includes three stages: approach process, turning process, and berthing process. In the approach process, the appropriate approach speed was select according to the rotation angle. In the turning process, the right and left propeller speed differences were select. In the berthing process, the berthing speed was controlled according to the berthing distance. In the port environment, a berthing simulation experiment for catamaran USV was carried out. The simulation results show that based on the berthing and maneuvering algorithm, the efficiency and safety of catamaran USV berthing can be improved.