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The Zhuque family, who lived in the Hexi Corridor on the ancient Silk Road, established LANDSPACE and has been exploring environmental, economic, and safety propellants. Little Zhuque visited LANDSPACE and learned about various liquid propellants, including liquid oxygen and kerosene with high thrust but easy carbon accumulation, environmentally friendly liquid oxygen and liquid hydrogen with high energy consumption, stable but toxic unsymmetrical dimethylhydrazine and nitrogen tetroxide. Finally, they discovered that the Zhuque Two carrier rocket, launched by LANDSPACE, was the world's first rocket to use liquid oxygen and methane as propellants. Liquid oxygen and methane are expected to have broader applications in the future due to their abundant reserves, easy storage conditions, safe transportation, complete combustion, and pollution-free combustion products. [ABSTRACT FROM AUTHOR]

The melanocortin-3 receptor (MC3R) regulates GABA release from agouti-related protein (AgRP) nerve terminals and thus tonically suppresses multiple circuits involved in feeding behavior and energy homeostasis. Here, we examined the role of the MC3R and the melanocortin system in regulating the response to various anorexigenic agents. The genetic deletion or pharmacological inhibition of the MC3R, or subthreshold doses of an MC4R agonist, improved the dose responsiveness to glucagon-like peptide 1 (GLP1) agonists, as assayed by inhibition of food intake and weight loss. An enhanced anorectic response to the acute satiety factors peptide YY (PYY3-36) and cholecystokinin (CCK) and the long-term adipostatic factor leptin demonstrated that increased sensitivity to anorectic agents was a generalized result of MC3R antagonism. We observed enhanced neuronal activation in multiple hypothalamic nuclei using Fos IHC following low-dose liraglutide in MC3R-KO mice (Mc3r–/–), supporting the hypothesis that the MC3R is a negative regulator of circuits that control multiple aspects of feeding behavior. The enhanced anorectic response in Mc3r–/– mice after administration of GLP1 analogs was also independent of the incretin effects and malaise induced by GLP1 receptor (GLP1R) analogs, suggesting that MC3R antagonists or MC4R agonists may have value in enhancing the dose-response range of obesity therapeutics. [ABSTRACT FROM AUTHOR]

Emergency management attends to expedite the emergency response and mitigate the impact on human lives and the economy caused by emergency incidents. One of the primary tasks of emergency management is ensuring that emergency response teams arrive at the incident location within a specified time frame. Previous studies have focused on reducing response times by identifying optimal locations for emergency vehicles (EVs) and emergency departments, assigning EV to a call, designating the optimal dispatch routes, and giving priority to emergency vehicles at traffic lights (Chen et al., 2014; Panahi & Delavar, 2008). However, despite these efforts, many emergency vehicles still miss their target response time. A comprehensive analysis is lacking to evaluate geographical environmental variables contributing to unsuccessful and successful emergency dispatches. Exploring the relationship between the geographical environment and emergency dispatch to improve emergency response services in neighbourhoods, this study aimed to identify geographic environmental determinants that differentiate successful and unsuccessful dispatches: (1) road characteristics, (2) topology of street segments, (3) weather conditions, (4) land use, (5) time and (6) dispatch operations (e.g., number of dispatched vehicles). [ABSTRACT FROM AUTHOR]

Phenolics in food and fruit tree leaves exist in free, soluble-conjugate, and insoluble-bound forms. In this study, in order to enhance the bioavailability of insoluble-bound phenolics from guava leaves (GL), the ability of enzyme-assisted extraction in improving the release of insoluble-bound phenolics was investigated. Compared to untreated GL, single xylanase-assisted extraction did not change the composition and yield of soluble phenolics, whereas single cellulase or b-glucosidaseassisted extraction significantly enhanced the soluble phenolics content of PGL. However, complex enzyme-assisted extraction (CEAE) greatly improved the soluble phenolics content, flavonoids content, ABTS, DPPH, and FRAP by 103.2%, 81.6%, 104.4%, 126.5%, and 90.3%, respectively. Interestingly, after CEAE, a major proportion of phenolics existed in the soluble form, and rarely in the insoluble-bound form. Especially, the contents of quercetin and kaempferol with higher bio-activity were enhanced by 3.5- and 2.2-fold, respectively. More importantly, total soluble phenolics extracts of GL following CEAE exhibited the highest antioxidant activity and protective effect against supercoiled DNA damage. This enzyme-assisted extraction technology can be useful for extracting biochemical components from plant matrix, and has good potential for use in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

A single dominantly expressed allele of major histocompatibility complex class I (MHC I) may be responsible for the duck's high tolerance to highly pathogenic influenza A virus (HP-IAV) compared to the chicken's lower tolerance. In this study, the crystal structures of duck MHC I (Anpl-UAA*01) and duck β2-microglobulin (β2m) with two peptides from the H5N1 strains were determined. Two remarkable features were found to distinguish the Anpl-UAA*01 complex from other known MHC I structures. A disulfide bond formed by Cys95 and Cys112 and connecting the β5 and β6 sheets at the bottom of peptide binding groove (PBG) in Anpl-UAA*01 complex, which can enhance IAV peptide binding, was identified. Moreover, the interface area between duck MHC I and β2m was found to be larger than in other species. In addition, the two IAV peptides that display distinctive conformations in the PBG, B, and F pockets act as the primary anchor sites. Thirty-one IAV peptides were used to verify the peptide binding motif of Anpl-UAA*01, and the results confirmed that the peptide binding motif is similar to that of HLA-A*0201. Based on this motif, approximately 600 peptides from the IAV strains were partially verified as the candidate epitope peptides for Anpl-UAA*01, which is a far greater number than those for chicken BF2*2101 and BF2*0401 molecules. Extensive IAV peptide binding should allow for ducks with this Anpl-UAA*01 haplotype to resist IAV infection. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the clinical efficacy of neoadjuvant chemotherapy combined with surgery in primary synovial sarcoma of the limbs and trunk through retrospective analysis of patients with primary synovial sarcoma of the limbs and trunk treated by this treatment in our hospital. Methods: A total of 89 patients diagnosed with synovial sarcoma were enrolled in this study between January 2005 and December 2011 in PLA General Hospital. Most of the patients received neoadjuvant chemotherapy combined with operative treatment (84.3%), 10.1% of them received adjuvant chemotherapy combined with operative treatment, and only 5.6% received merely operative treatment. The influence on the prognosis of patients with synovial sarcoma was analyzed by the statistics overall survival (OS), progression-free survival (PFS), local control (LC), and freedom from distant metastasis (FFDM). Results: The median follow-up time was 68.6 months. The 5-year OS, 5-year PFS, 5-year LC, and 5-year FFDM of the patients were 80.2, 60.5, 78.8, and 80.8%, respectively. The OS of the patients with a tumor size >5 cm was lower (91.4 vs 73.1%, P < 0.05). Besides, the OS and FFDM of neoadjuvant chemotherapy were better than those of adjuvant chemotherapy (84.5 vs 55.6%, P = 0.015, and 83.8 vs 55.6%, P = 0.028, respectively). However, there was no significant difference in the LC and PFS. Conclusions: Neoadjuvant chemotherapy was beneficial for patients with synovial sarcoma, and it could improve survival time and control distant metastasis. Tumor size was an important factor influencing patients' prognosis. [ABSTRACT FROM AUTHOR]

The lack of a peptide-swine leukocyte antigen class I (pSLA I) complex structure presents difficulties for the study of swine cytotoxic T lymphocyte (CTL) immunity and molecule vaccine development to eliminate important swine viral diseases, such as influenza A virus (IAV). Here, after cloning and comparing 28 SLA I allelic genes from Chinese Heishan pigs, pSLA-3*hs0202 was crystalized and solved. SLA-3*hs0202 binding with s&#9462m and a KMNTQFTAV (hemagglutinin [HA]-KMN9) peptide from the 2009 pandemic swine H1N1 strain clearly displayed two distinct conformations with HA-KMN9 peptides in the structures, which are believed to be beneficial to stimulate a broad spectrum of CTL immune responses. Notably, we found that different HA-KMN9 conformations are caused, not only by the flexibility of the side chains of residues in the peptide-binding groove (PBG), but also by the skewing of α1 and α2 helixes forming the PBG. In addition, alanine scanning and circular-dichroism (CD) spectra confirmed that the B, D, and F pockets play critical biochemical roles in determining the peptide-binding motif of SLA-3*hs0202. Based on biochemical parameters and comparisons to similar pockets in other known major histocompatibility complex class I (MHC-I) structures, the fundamental motif for SLA-3*hs0202 was determined to be X-(M/A/R)-(N/Q/R/F)-X-XX- X-X-(V/I) by refolding in vitro and multiple mutant peptides. Finally, 28 SLA-3*hs0202-restricted epitope candidates were identified from important IAV strains, and two of them have been found in humans as HLA-A*0201-specific IAV epitopes. Structural and biochemical illumination of pSLA-3*hs0202 can benefit vaccine development to control IAV in swine. [ABSTRACT FROM AUTHOR]

In this paper, we numerically study the effect of autapse on the synchronization of Newman-Watts small-world Hodgkin-Huxley neuron network. It is found that the neurons exhibit synchronization transitions as autaptic self-feedback delay is varied, and the phenomenon becomes strongest when autaptic self-feedback strength is optimal. This phenomenon also changes with the change of coupling strength and network randomness and become strongest when they are optimal. There are similar synchronization transitions for electrical and chemical autapse, but the synchronization transitions for chemical autapse occur more frequently and are stronger than those for electrical synapse. The underlying mechanisms are briefly discussed in quality. These results show that autaptic activity plays a subtle role in the synchronization of the neuronal network. These findings may find potential implications of autapse for the information processing and transmission in neural systems. [ABSTRACT FROM AUTHOR]

At the current stage of chemosensor chemistry, the critical question now is whether the heavy atom effect caused by HTM ions can be blocked or avoided. In the present work, we provide unequivocal evidence to confirm that the heavy atom effect of Hg2+ is inhibited by water and other solvent molecules based on results using the chemosensor L. Most importantly, the heavy atom effect and blocking thereof were monitored within the same system by the use of ratiometric fluorescence signal changes of the pyrene motif. These observations not only serve as the foundation for the design of new 'turnon' chemosensors for HTM ions, but also open up new opportunities for the monitoring of organic reactions. [ABSTRACT FROM AUTHOR]

EBI2 is known as a kind of 7TM G protein-coupled receptors, and EBi2 gene is one of the most upregulated genes in Epstein-Barr virus (EBV)-infected lymphocytes. As a constitutively active receptor, EBI2 signals via Gαi, and TM-II plays an important role in the signal transduction process. EBI2 is expressed mainly in mature B cells and the expression level increases at the early stage of activation; subsequently, B cells are transferred into GC and the expression level is down-regulated. EBI2 can regulate independently and mediate synergistically the migration of B cell towards the extrafollicular areas and GC depending on chemokine receptors CXCR5 and CCR7 (EBI1). Differential expression of EBI2 receptor is conducive to accurate migration of B cells at different stages, thereby leading to appropriate immunologic responses to T-dependent antigens. Recently, two research groups identified a specific oxysterol as the natural ligand for EBI2. Among all the oxysterols, 7α, 25-Dihydroxycholesterol (7α, 25-OHC) is the most effective ligand and activator, and EBI2-Oxysterol signal pathway plays an important role in adaptive immune responses. In addition, EBI2 is also closely related with specific kinds of autoimmune diseases, so it is considered as a negative regulator of the innate immune response in macrophages. [ABSTRACT FROM AUTHOR]

Understanding where and when events happened provides a foundation to explore why and how the events took place and to predict their occurrences. Point events, such as traffic accidents, disease cases, and criminal activities, are common in spatial clustering or hotspot analysis. These spatiotemporal clusters or hotspots are subject to two disadvantages. First, the clusters can disappear and re-appear due to varying spatial and temporal units or be subject to the modifiable area unit problem (MAUP). Second, the clusters are fixed in space and time. So, analyses focus on clusters may overlook the correlation among clusters and the repeated point-events. Instead, this research focuses on track the timing and subsequent events, which means detecting where point events routinely occur and how site characteristics and situation dynamics at these locations may explain the routine occurrences. We develop the algorithm, location analytics of routine occurrences (LARO) to uncover locations where events occur routinely. We demonstrate the method with a case study of over 250,000 reported traffic accidents from 2010 to 2018 in Dallas, Texas, the United States of America. We assume that the locations of routine traffic accidents reflect the patterns of life in Dallas' human dynamics and use points of interest (POIs) to reckon the site characteristics and situation dynamics surrounding these locations. LARO first identifies the routine occurrences by exploiting the periodicity of point events, which in turn determines the proper temporal units of analysis to detect locations of routine occurrences. The periodicity indicates that a value repeats itself in a regular time interval. An approach, discrete Fourier transformation (DFT), identifies the underlying patterns by transforming data items from the time domain to the frequency domain and using Fourier analysis to find the dominant periodicities. The periodic pattern, we coin as routine occurrences, takes place hourly, daily, weekly, or in another period. The general idea of DFT is to discretize time into a temporal bin and distributes point-events into respective temporal units. The result is a frequency distribution of point events over time. We use Fourier transformations to aggregate traffic crash counts at 1-h intervals during weekdays and separately during weekends. Our findings show that traffic accidents follow robust temporality with hour-of-the-day (HOD) and day-of-the-week (DOW) (Figure 1). The multiple R2 of weekday transformation and weekend, transformation were 0.9598 and 0.823, while the adjusted R2 of the weekday transformation and weekend transformation were 0.9557 and 0.792. The second stage of LARO algorithms aims to detect the location of routine occurrences. Conventional approaches to detect clusters or hotspots are susceptible to MAUP. We use disaggregated data to overcome this problem and detect spatial-temporal routine occurrences based on each event and its proximity events. The consideration of proximity is common in criminology, which means that when a crime occurs at a specific location, the surrounding area may experience similar crimes occurring over a period. Based on the idea of proximity, we consider the proximity in our study as a pattern that subsequent events successively occur in proximity around the location of an existing event. The area of spatial proximity is determined by the road network in Dallas, which is one-half of the average size of a city block (~ 750m). The algorithm identifies the hour of a day (HOD) and the day of a week (DOW) of one event at a time and finds all events occurring at the same HOD and DOW within the set spatial proximity. The ability to measure spatiotemporal proximity over time could provide valuable insight into the location of existing events experiencing an increasing, a decreasing, or a constant number of subsequent events over time (Figure 2). Locations in northern Dallas experience increasing subsequent proximate events over years, locations in central Dallas have notable proximate events in 2018, locations in Eastern Dallas exhibit a constant number of proximate events over time, and locations in Southern Dallas show decreasing frequency over the years. The qualification of the location of routine occurrence varies with temporal units. If a location has an event occurring every Tuesday at 7 am, the maximal number of reoccurrences will be 52 events per year. A threshold of 10 percent will require five events on Tuesday at 7 am and at least two consecutive years for the location qualification of routine occurrences. The third stage of LARO aims to examine the spatial features and their functions around the location of routine occurrences (ROL). We assume the human dynamics contribute to the traffic accident pattern due to the special temporal characteristics of human activities. The human dynamics support by various spatial features at locations at different times. Point of interest (POI) is one of the most popular ways to represents geographic entities (e.g., restaurant, park, and nightlife entertainment) with semantic data (e.g., name and function). They work as origin or destination venues for human mobility and can reflect the density of populated areas. To find out the distinctive combinations of spatial features surrounding the detected locations, we use the A-priori algorithm to extract frequent spatial features and generate association rules between two geographic classes, such as traffic accidents and POIs. Except for ROLs, we also differentiate the POI associations to other two locations (normal traffic accident locations and random locations with no traffic accident). In the end, the rules can give summative characteristics of the sites and situations at these three different locations. The output of this algorithm represents a location of point-event as lp(x, y, t, f) with location (x, y), time of occurrences (t), and a set of features (f) characterizing the location at fine units to differentiate from other locations. Among them, the spatial features characterize that most frequently (at the fourth quantile, > 75% of all the same POIs in Dallas) POIs appear around the ROLs are of parks, parking lots, and entertainment places. Specifically, rules between ROLs and high frequencies of these POIs with the support of almost 21% and confidence of almost 85%. These indicate that 21% of locations with high frequencies of these POIs are within 750m of ROLs, and around 85% of all ROLs are within 750m of locations with high frequencies of these POIs. While for normal and random locations, they associated with low frequencies (at the first quantile, < 25% of all the same POIs in Dallas) of POIs. This study enriches the geographical meaning of the location of events based on these attributes; a location can be not only a place to support event occurrences but also serves an interrelating role that interacts with time, proximity geographical dynamics, and nearby spatial features. The better quantification of the dynamic evolution of the locations of events provides greater insights as to the relevant department. For the location of routine occurrences, appropriate mitigation measures can be applied according to the time of occurrences and spatial features around the location. [ABSTRACT FROM AUTHOR]

TLRs are critical innate immune sensors in the induction of proinflammatory cytokines to eliminate invading pathogens. However, the mechanisms for the full activation of TLR-triggered innate immune response need to be fully understood. The murine CMRF-35-like molecule (CLM)-3 is a representative of CLM family belonging to the Ig superfamliy. Considering that CLM-3 is selectively expressed in macrophages and the roles of CLM members in innate immune response remain unclear, in this study we investigated the role of CLM-3 in the regulation of TLR-triggered innate response. We found that CLM-3 was an endosome/lysosome-localized molecule, and was downregulated in macrophages by stimulation with TLR9 ligand, but not TLR4 and TLR3 ligands. Interestingly, CLM-3 selectively promoted production of TNF-α and IL-6 in macrophages triggered by TLR9, but not TLR4 or TLR3. CLM-3 enhanced activation of MAPKs and NF-κB pathways in TLR9-triggered macrophages. Furthermore, CLM-3-transgenic mice were generated, and CLM-3 expression was confirmed by mAb against CLM-3 that we prepared. Accordingly, the macrophages derived from CLM-3-transgenic mice were more sensitive to TLR9 ligand stimulation, with more pronounced production of TNF-α, IL-6, and increased activation of MAPKs and NF-κB pathways. Moreover, ubiquitination of TNFR-associated factor 6, a crucial signaling transducer of TLR-triggered MAPKs and NF-κB activation, was found to be significantly promoted by CLM-3 in macrophages. Collectively, the endosome/lysosome-localized CLM-3 can promote full activation of TLR9-triggered innate responses by enhancing TNFR-associated factor 6 ubiquitination and subsequently activating MAPKs and NF-κB. [ABSTRACT FROM AUTHOR]

We theoretically demonstrate a kind of plasmon coupled cavity to achieve a nanolaser with high intensity and low threshold. The plasmon cavity is composed of the gold film substrate and gold disk array, which supports two strong coupled resonance modes (i.e. surface plasmon polariton (SPP) and localized surface plasmon (LSP)). Compared with the nanolaser with the LSP resonance structure, the scattering cross-section of the LSP-SPP coupled laser is 80 times higher. The coupled cavity nanolaser with different wavelengths can be excited with different plasmon resonance modes by selecting the appropriate gain medium. In addition, a compact tunable dual-wavelength laser can be developed using this coupled structure. [ABSTRACT FROM AUTHOR]

Objective: Little is known about the association between maternal history of dysmenorrhea and perinatal outcomes. The aim of this study was to investigate the association between maternal history of dysmenorrhea and low birth weight (LBW). Methods: A total of 6754 pregnant women were recruited from the ongoing prospective cohort study in Guangxi, China, in 2015–2018. Information on the maternal history of dysmenorrhea was obtained by questionnaires including visual analog scale (VAS) questions during the first antenatal care visit. The association of maternal history of dysmenorrhea and LBW was evaluated using logistic regression analyses adjusted for confounding factors (infant sex, maternal age, parity, pre-pregnancy body mass index (BMI) (kg/m² ), gestational age, alcohol use during pregnancy, passive smoking, and occupational status). Results: Mothers with a history of dysmenorrhea were more likely to give birth to LBW infants (adjusted odds ratio (OR)=1.44; 95% confidence interval (CI): 1.12, 1.83). Among women with a history of dysmenorrhea, women 29 years old (adjusted OR 1.46; 95% CI 1.02, 2.10), multiparous (adjusted OR 1.59, 95% CI 1.12, 2.25), and women gave birth to female infant (adjusted OR = 1.53, 95% CI = 1.11, 2.11) had a higher risk of LBW. Conclusions: As the first cohort study to investigate the association between maternal history of dysmenorrhea and LBW, our study shows that dysmenorrhea may increase the risk of LBW. [ABSTRACT FROM AUTHOR]

In this paper, we study stochastic resonance (SR) induced by channel noise in adaptive weighted Newman-Watts networks of Hodgkin-Huxley neurons with channel blocking (CB). It is found that the intrinsic SR is dependent on adaptive coupling and is strongly enhanced when the changing rate of adaptive coupling is optimal, and this phenomenon is independent of sodium and potassium CB levels. As CB increases, the channel noise for SR decreases, but the strength of intrinsic SR nearly does not change in the presence of adaptive coupling, which is different from the case for fixed coupling. These results show that intrinsic SR can be enhanced and optimized by adaptive coupling, and CB's effect on the intrinsic SR can be reduced by adaptive coupling. This implies that adaptive coupling could more efficiently improve the time precision of information processing in neural systems. [ABSTRACT FROM AUTHOR]

• The solving model of optimum polarization angle is established. • On the premise of the optimum polarization angle, the images are captured. • The image captured based on polarization information optimizes the image processing. • The pose is solved non-iteratively according to the constraints of a parallelogram. As for vision-based pose estimation, which is also known as the PnP problem, non-iterative algorithms are more efficient. Precise extraction of 2D projections of feature points is important. If the projections of the feature points are not accurately extracted, the pose estimation accuracy is reduced. Under the condition of natural light, a camera captures the images of feature points, and the existence of high-light regions in the image affects the extraction accuracy of 2D projections of feature points, which reduces the number of effective feature points and leads to poor pose estimation accuracy. In the redundant cases (n > 4), redundant feature points are introduced as additional information, increasing the number of effective feature points to reduce the impact of high-light regions and improve the pose estimation accuracy. For the non-redundant cases (n = 4), it was difficult to ensure pose estimation accuracy. To solve this problem, a non-iterative pose estimation method based on the optimum polarization angle via four corner points of a parallelogram was proposed in this study. First, a model for solving optimum polarization angle was established. Thereafter, on the premise of the optimum polarization angle, the images were captured. Finally, the projections of the four corner points of a parallelogram were extracted, and the object pose was solved non-iteratively according to the four corner points. The corner point extraction experimental results show that the slope difference between the two parallel sides of each parallelogram under the condition of optimum polarization angle is less than that under the condition of natural light, thereby proving the improvement of the imaging quality. Measurement accuracy verification experiments prove that our pose estimation algorithm and the optimum polarization angle is the best combination to improve the non-iterative pose estimation accuracy in non-redundant cases. In the measurement range of −60-+60°, the angle measurement error was less than ±0.0491°. In the measurement range of 0–20 mm, the displacement measurement error was less than ±0.0435 mm. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) infection eliminates production of type I interferons (IFNs) in host cells, which triggers an antiviral immune response through the induction of downstream IFN-stimulated genes (ISGs), thus escaping the fate of host-mediated clearance. The IFN-induced transmembrane 3 (IFITM3) has recently been identified as an ISG and plays a pivotal role against enveloped RNA viruses by restricting cell entry. However, the role of IFITM3 in PRRSV replication is unknown. The present study demonstrated that overexpression of IFITM3 suppresses PRRSV replication, while silencing of endogenous IFITM3 prominently promoted PRRSV replication. Additionally, it was shown that IFITM3 undergoes S-palmitoylation and ubiquitination modification, and both posttranslational modifications contribute to the anti-PRRSV activity of IFITM3. Further study showed that PRRSV particles are transported into endosomes and then into lysosomes during the early stages of infection, and confocal microscopy results revealed that PRRSV particles are transported to IFITM3-positive cellular vesicles. By using a single virus particle fluorescent labeling technique, we confirmed that IFITM3 can restrict PRRSV membrane fusion by inducing accumulation of cholesterol in cellular vesicles. Additionally, we found that both endogenous and exogenous IFITM3 are incorporated into newly producing PRRS virions and diminish viral intrinsic infectivity. By using cell coculture systems, we found that IFITM3 effectively restricted PRRSV intercellular transmission, which may have been caused by disrupted membrane fusion and reduced viral infectivity. In conclusion, our results demonstrate, for the first time, that swine IFITM3 interferes with the life cycle of PRRSV, and possibly other enveloped arteritis viruses, at multiple steps. [ABSTRACT FROM AUTHOR]

Wetlands are sensitive, easily disturbed, and globally important ecosystems which face lots of threats, such as global climate change and local human activities. Those might result in the degradation of wetlands. The relationship between hydrological connectivity and the degradation of wetlands has gained prominence among researchers as a simple way to quickly evaluate the degradation of wetlands. This metric is responsive to preferential flow, which can, to some extent, indicate hydrological connectivity. To quantify hydrological connectivity at soil column scales, we explored the relationships between soil properties and the strength of preferential flow in samples from a degrading wetland in which Chinese tamarisk (Tamarix chinensis Lour.) grow in the Yellow River Delta. We conducted laboratory solute penetration tests through the undisturbed soil sample columns and analyzed the relationship between the solute penetration test results and preferential flow. We then verified the applicability of the dual-permeability model to predict the results of the solute penetration test. Our results revealed that the discharge rate from the soil columns was the highest in samples from 20 to 40 cm soil depth and that the flow of discharge concentration remained stable for a long time before increasing rapidly, which exhibited rich medium porosity and macroporosity. We associated this with some improvement in hydrological connectivity, which was also consistent with our dual-permeability simulation results. In the future experimental operation, we can preliminarily predict the hydrological connectivity and preferential flow intensity of soil column by using the dual-permeability model with the discharge data of solute penetration test, which can help us know quickly to what extent are wetlands degraded. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) pollution in Beijing is becoming an increasingly serious problem and is thus attracting considerable scientific attention. In order to reveal the characteristics and source of PM2.5 and its components, observations of PM2.5, water-soluble ions, elemental carbon (EC), and organic carbon (OC) were conducted in the urban green belt of Beijing from April 2016 to April 2017. The annual average concentrations of PM2.5, EC, OC, SO42-, NO3-, and NH4 +were found to be 124.02, 10.21, 30.73, 36.84, 27.63, and 16.87 µg/m³, respectively. Moreover, the ratios of OC/EC, NO3 -/SO42- were 2.58 and 0.75, respectively, and calculated secondary organic carbon concentration was 9.75 µg/m³ These results indicate that: 1) PM2.5 pollution in the urban green belt of Beijing is more serious than in many other cities in China and has increased considerably over a period of five years; 2) there is a considerable variation in both the total PM2.5 concentration and composition of water-soluble ions throughout different seasons, while the forest belt width has no evident influence on the PM concentration and water-soluble ions; 3) OC and EC concentrations and the ratio of OC/EC shows that traffic emissions during summer are higher than in other seasons and that traffic emissions are the dominant carbon source in Beijing. Furthermore, the carbon contribution to total PM2.5 is greater than in other cities. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles (NPs) possessing peroxidase-like catalytic activity have been widely explored in recent decades, owing to their high stability against harsh conditions, low cost, flexibility in structure design and composition, adjustable activities and excellent biocompatibility in comparison with natural enzymes. Recently, a lot of great achievements have been made in this field of iron oxide nanozymes, however, this research has now reached a bottleneck in that the maximum activity enhancement is difficult to achieve via a material design. Hence, in this work, visible light was introduced to improve the peroxidase-like activity of Fe2O3 NPs synthesized via a combination of electrospinning technology and hydrothermal reaction. Our results showed that with the assistance of visible light, Fe2O3 NPs exhibited at least 2.2-fold higher peroxidase activity than those tested under darkness, confirming the superiorly visible light promoted peroxidase-like catalytic activity of Fe2O3 NPs. Furthermore, the affinity and maximum reaction velocity of Fe2O3 nanoflowers (bandgap = 1.78 eV) towards 3,3’,5,5’-tetramethylbenanozymeidine (TMB) were at least over 3.7 and 4.3 times greater than in Fe2O3 nanocubes (bandgap = 2.08 eV), suggesting that the reaction performance of semiconductors could be controlled by proper adjustment of the bandgap. Moreover, the Fe2O3 NPs were also successfully utilized to detect glucose. Herein, we believe that the present work exhibits a fascinating perspective for peroxidase-like catalytic fields. [ABSTRACT FROM AUTHOR]

The central solenoid (CS) model coil (CSMC), which has a high stored energy, is developed to validate the CS manufacturing methods for the China Fusion Engineering Test Reactor (CFETR). The designed operation current of the model coil is 47.65 kA. The maximum rate of the magnetic field is 1.5 T/s. The stored energy of the model coil is 407.6 MJ. A set of verification test of the model coil will be conducted after manufacture, so a CSMC power supply, which generates the current for coil operation, and a quench protection, which could quickly release the stored energy, are required. The main circuit topology of power supply was designed according to the requirements of the testing current waveform. The current control was adopted, which controlled the actual output current provided by the power supply system to track any specified current reference of the model coil within acceptable precision. The design of the quench protection system for model coil was also described in this paper. [ABSTRACT FROM AUTHOR]

The China fusion engineering test reactor is a new tokamak device. The central solenoid (CS) model coil, which is responsible for developing and verifying the key manufacturing methods of a superconducting magnet, is now under engineering design. The rating current of the coil is 47.65 kA and total magnetically stored energy reaches 407 MJ, so a quench protection is required to discharge this huge stored energy. This paper gives a description of the quench protection of CS model coil. The circuit of the quench protection system is designed, which consists of the direct current circuit breaker, discharge resistor, diode, and fuse. The main parameters of these components were selected. The control system of quench protection is also introduced. [ABSTRACT FROM AUTHOR]

The CD8αα homodimer structures of endotherms demonstrate that despite distinct diversity at the amino acid sequence level, a few conserved key amino acids ensure common structural features. The structure of CD8αα in ancient ectotherms, such as lower bony fish, remains unclear. In this study, the high-resolution structure of the grass carp ( Ctenopharyngodon idella ) CD8αα (Ctid-CD8αα) homodimer was determined using the single-wavelength anomalous diffraction (SAD) method. The structure of Ctid-CD8αα shows distinct differences from the known CD8αα structures of endotherms, including a distinct topological structure with shorter back β sheets. The configuration and distribution of the hydrophobic core are different from those in endotherms. Interestingly, mutation of the key amino acid F32S, which is very common in fish and lies in the CDR loop region, leads to the absence of the typical cavity that binds to an epitope-MHC I (p/MHC I) in endotherms, yet Ctid-CD8αα can still specifically bind the grass carp peptide-Ctid-UAA-β2m (p/UAA-β2m). Our results indicate that during the evolutionary process, CD8αα has undergone dramatic changes that affect its dimeric structure and may use a new strategy to interact with p/MHC I. [ABSTRACT FROM AUTHOR]

The emergence of adaptive immunity in jawed vertebrates depended on the appearance of variable immune receptors, BCRs and TCRs, which exhibit variable-J-constant (VJ-C)-type Ig superfamily folds. Hitherto, however, the structures of IgV-J-IgC-type molecules had never been characterized in invertebrates, leaving the origin of BCR/TCR-type molecules unknown. Using x-ray crystallography, the structure of a VJ-C2 molecule, named AmpIgVJ-C2, was determined in amphioxus (Branchiostoma floridae). The first domain shows typical V folding, including the hydrophobic core, CDR analogs, and eight conserved residues. The second domain is a C2-type Ig superfamily domain, as defined by its short length and the absence of β-strand D- and C1-typical motifs. AmpIgVJ-C2 molecules form homodimers, using "three-layer packing dimerization," as described for TCRs and BCRs. The AmpIgVJ-C2 V domain harbors a diglycine motif in β-strand G and forms a β-bulge structure participating in V-V intermolecular interaction. By immunohistochemistry, AmpIgVJ-C2 molecules were primarily found in mucosal tissues, whereas PCR and sequence analysis indicated considerable genetic variation at the single-gene level; these findings would be consistent with an immune function and a basic ability to adapt to binding different immune targets. Our results show a BCR/TCR-ancestral like molecule in amphioxus and help us to understand the evolution of the adaptive immune system. [ABSTRACT FROM AUTHOR]

Feline immunodeficiency virus (FIV) infection in domestic cats is the smallest usable natural model for lentiviral infection studies. FLA-E*01801 was applied to FIV AIDS vaccine research. We determined the crystal structure of FLAE* 01801 complexed with a peptide derived from FIV (gag positions 40 to 48; RMANV STGR [RMA9]). The A pocket of the FLA-E*01801 complex plays a valuable restrictive role in peptide binding. Mutation experiments and circular-dichroism (CD) spectroscopy revealed that peptides with Asp at the first position (P1) could not bind to FLA-E*01801. The crystal structure and in vitro refolding of the mutant FLA-E*01801 complex demonstrated that Glu63 and Trp167 in the A pocket play important roles in restricting P1D. The B pocket of the FLA-E*01801 complex accommodates M/T/A/V/I/L/S residues, whereas the negatively charged F pocket prefers R/K residues. Based on the peptide binding motif, 125 FLA-E*01801-restricted FIV nonapeptides (San Diego isolate) were identified. Our results provide the structural basis for peptide presentation by the FLA-E*01801 molecule, especially A pocket restriction on peptide binding, and identify the potential cytotoxic T lymphocyte (CTL) epitope peptides of FIV presented by FLA-E*01801. These results will benefit both the reasonable design of FLA-E*01801-restricted CTL epitopes and the further development of the AIDS vaccine. [ABSTRACT FROM AUTHOR]

The new solid forms screening of sulfamethazine was conducted in 16 kinds of different pure solvents. Four new sulfamethazine solvates were reported for the first time, and three crystal structures of solvates were successfully determined from single-crystal X-ray diffraction data. The results showed that sulfamethazine solvate formation directly depended on the solvents used in the experiments. The solvent properties were used to evaluate the effects of solvent on solvate formation. It was found that the H-bond acceptor ability of the solvent was the main factor that governed the solvate formation. The H-bonded motifs in the structures of solvates have been fully characterized. The results revealed that sulfamethazine solvate formation was mainly driven by molecular self-assembly through hydrogen bonding between solvent and solute molecules. Meanwhile, the crystal structures results also showed that the sulfamethazine molecule had flexible conformation. Furthermore, the principles of different sulfamethazine molecules packing in different crystal structures were discussed from the view of molecular intermolecular interactions and the molecular conformation. [ABSTRACT FROM AUTHOR]

MHC molecules evolved with the descent of jawed fishes some 350-400 million years ago. However, very little is known about the structural features of primitive MHC molecules. To gain insight into these features, we focused on the MHC class I Ctid-UAA of the evolutionarily distant grass carp (Ctenopharyngodon idella). The Ctid-UAA H chain and β2-microglobulin (Ctid-β2m) were refolded in vitro in the presence of peptides from viruses that infect carp. The resulting peptide-Ctid-UAA (p/Ctid-UAA) structures revealed the classical MHC class I topology with structural variations. In comparison with known mammalian and chicken peptide-MHC class I (p/MHC I) complexes, p/Ctid-UAA structure revealed several distinct features. Notably, 1) although the peptide ligand conventionally occupied all six pockets (A-F) of the Ag-binding site, the binding mode of the P3 side chain to pocket D was not observed in other p/MHC I structures; 2) the AB loop between β strands of the α1 domain of p/Ctid-UAA complex comes into contact with Ctid-β2m, an interaction observed only in chicken p/BF2*2101-bβm complex; and 3) the CD loop of the α3 domain, which in mammals forms a contact with CD8, has a unique position in p/Ctid-UAA that does not superimpose with the structures of any known p/MHC I complexes, suggesting that the p/Ctid-UAA to Ctid-CD8 binding mode may be distinct. This demonstration of the structure of a bony fish MHC class I molecule provides a foundation for understanding the evolution of primitive class I molecules, how they present peptide Ags, and how they might control T cell responses. [ABSTRACT FROM AUTHOR]

• The line formed by every two calibration points is expressed by two independent constraints. • These two independent constraints are considered in the extrinsic parameters calibration. • There is no iterative step under the condition of ensuring the calibration accuracy. The calibration accuracy of the binocular stereo vision system is important for precision measurement. The extrinsic parameters (structure parameters), which describe the relative position of the two cameras, need to be optimized before measurement. The optimization of extrinsic parameters is accomplished through iterations of minimizing an objective function. It is hard to decide the optimum objective function between various objective functions. The calibration accuracy is decreased when the objective function is incorrect, which can result in excessive optimization or fall into a local minimum (ambiguous solution), notably for planar targets. In this paper, we proposed a non-iterative calibration method for the extrinsic parameters of binocular stereo vision considering the line constraints of a planar target. Each line formed by every two calibration points can provide two independent constraints. Additional equations for solving the extrinsic parameters can be obtained using these constraints. We added these equations to the equations system established by the homography of the target plane and image plane. The extrinsic parameters of the binocular stereo vision system can be solved non-iteratively. Using the parameters calibrated by our method, greater improvements in the accuracy and stability of measurements occurred, compared to other existing methods. In the −45° to +45° measuring range, the maximum measurement error is no more than 0.037° and the average measurement error is no more than 0.022°. In the 0 to 28 mm measuring range, the maximum measurement error is no more than 0.039 mm and the average measurement error is no more than 0.012 mm. The maximum length measurement error is no more than 0.038 mm and the average length measurement error is no more than 0.011 mm while measuring a 240 × 180 mm2 target. [ABSTRACT FROM AUTHOR]

MHC class I (MHC I)-restricted virus-specific CTLs are implicated as critical components in the control of this naturally occurring lentivirus and in the protective immune response to the successfully applied attenuated equine infectious anemia virus vaccine in the horse. Nevertheless, the structural basis for how the equine MHC I presents epitope peptides remains unknown. In this study, we investigated the binding of several equine infectious anemia virus-derived epitope peptides by the ability to refold recombinant molecules and by thermal stability, and then by determining the x-ray structure of five peptide-MHC I complexes: equine MHC class 1 allele (Eqca)-N*00602/Env-RW12, Eqca-N*00602/Gag-GW12, Eqca-N*00602/Rev-QWll, Eqca-N*00602/ Gag-CF9, and Eqca-N*00601/Gag-GW12. Although Eqca-N*00601 and Eqca-N*00602 differ by a single amino acid, Eqca- N*00601 exhibited a drastically different peptide presentation when binding a similar CTL epitope, Gag-GW12; the result makes the previously reported function clear to be non-cross-recognition between these two alleles. The structures plus Eqca-N*00602 complexed with a 9-mer peptide are particularly noteworthy in that we illuminated differences in apparent flexibility in the center of the epitope peptides for the complexes with Gag-GW12 as compared with Env-RW12, and a strict selection of epitope peptides with normal length. The featured preferences and unconventional presentations of long peptides by equine MHC I molecules provide structural bases to explain the exceptional anti-lentivirus immunity in the horse. We think that the beneficial reference points could serve as an initial platform for other human or animal lentiviruses. [ABSTRACT FROM AUTHOR]

Inflammatory pseudotumors (IPT) are soft tissue tumors that include a diverse group of lesions characterized by inflammatory cell infiltration and variable fibrotic responses. Idiopathic orbital inflammatory pseudotumors (IOIP) are IPTs of unknown etiology that develop in the orbit. Due to the lack of well-defined pathogenic mechanisms, diagnosis and treatment of this disease remain a significant challenge. Epstein-Barr virus (EBV) infection, which causes significant lymphocyte infiltration, has been proposed to be involved in IOIP. This study tries to validate the relationship between EBV infection and the development of IOIP. Sixteen IOIP tissue samples were obtained from patients during surgical resection of the lesion. One Graves' ophthalmopathy tissue sample and 20 normal donors' plasma serves as controls. The plasma level of five EBV antibodies, including VCA-IgG, VCA-IgA, VCA-IgM, EA-IgG and EBNA1-IgG were examined. All plasma samples were EB-VCA-IgG positive and EB-VCA-IgM negative, suggesting that all people tested had been infected with EBV but not in the acute infection stage. EBV-DNA was detected in 15/16 (94%) of IOIP tissue samples despite different levels of lymphocyte infiltration and 5/16 plasma samples (31%) were detected EBV DNA positive which is higher than the normal controls (10%). Percent of positive plus suspected positive samples with one or more of the three important risk markers (VCA-IgA, EA-IgG, EBV-DNA) is 50% of the patients (8/16) which is much higher compare with the normal controls (20%). The results further reveal the relationship between IOIP and EBV infection. [ABSTRACT FROM AUTHOR]

In this work, the rationally-designed sharp corners on Au nanorods tremendously improved the catalytic activity, particularly in the presence of visible light irradiation, towards the hydrogenation of 4-nitrophenol to 4-aminophenol. A strikingly increased rate constant of 50.6 g−1 s−1 L was achieved in M-Au-3, which was 41.8 times higher than that of parent Au nanorods under dark conditions. The enhanced activities were proportional to the extent of the protruding sharp corners. Furthermore, remarkably enhanced activities were achieved in novel ternary Au/RGO/TiO2 sheets, which were endowed with a 52.0 times higher rate constant than that of straight Au nanorods. These remarkably enhanced activities were even higher than those of previously reported 3–5 nm Au and 3 nm Pt nanoparticles. It was systematically observed that there are three aspects to the synergistic effects between Au and RGO sheets: (i) electron transfer from RGO to Au, (ii) a high concentration of p-nitrophenol close to dumbbell-like Au nanorods on RGO sheets, and (iii) increased local reaction temperature from the photothermal effect of both dumbbell-like Au nanorods and RGO sheets. [ABSTRACT FROM AUTHOR]

An abstract of the article "Establishment and Clinical Application of a Liquid Chip Technology for High Throughput Screening Pathogens of Acute Contagious Respiratory Disease?" by Yusheng Chen and colleagues is presented.