Search

Full-depth ocean zonal currents in the tropical and extratropical northwestern Pacific (TNWP) are studied using current measurements from 17 deep-ocean moorings deployed along the 143°E meridian from the equator to 22°N during January 2016-February 2017. Mean transports of the North Equatorial Current and North Equatorial Countercurrent are estimated to be 42.7 ± 7.1 Sv (1 Sv = 106 m³ s-1) and 10.5 ± 5.3 Sv, respectively, both of which exhibit prominent annual cycles with opposite phases in this year. The observations suggest much larger vertical extents of several of the major subsurface currents than previously reported, including the Lower Equatorial Intermediate Current, Northern Intermediate Countercurrent, North Equatorial Subsurface Current, and North Equatorial Undercurrent (NEUC) from south to north. The Northern Subsurface Countercurrent and NEUC are found to be less steady than the other currents. Seasonal variations of these currents are also revealed in the study. In the deep ocean, the currents below 2000 m are reported for the first time. The observations confirm the striation patterns of meridionally alternating zonal currents in the intermediate and deep layers. Further analyses suggest a superposition of at least the first four and two baroclinic modes to represent the mean equatorial and off-equatorial currents, respectively. Meanwhile, seasonal variations of the currents are generally dominated by the first baroclinic mode associated with the low-mode Rossby waves. Overall, the above observational results not only enhance the knowledge of full-depth current system in the TNWP but also provide a basis for future model validation and skill improvement. [ABSTRACT FROM AUTHOR]

Accurate analysis of the main chemical components of oil-bearing sludge is an important prerequisite for effective soil remediation and resource reuse. However, precise analysis of the extract components is difficult to achieve because of the mutual interference of saturates, aromatics, and resins, collectively called SAR, and asphaltene that are introduced during chloroform extraction. In this study, SAR was efficiently extracted using nheptane, while asphaltene components were retained in soil because of their insolubility in n-heptane. The maximum yield of SAR extraction was 27.0%, indicating an increase of 1.75% compared to chloroform extraction. The extracted SAR components were separated by chromatography and the main structural units and components were analyzed. The results show that saturates, aromatics, and resins have a single component, a high content of major components, and contain fewer impurities using nheptane extraction. Moreover, the solubility of asphaltene was inhibited during the effective extraction of SAR components with n-heptane and did not influence the subsequent analysis of SAR component. Efficient SAR extraction, accurate SAR component analysis, and high efficiency asphaltene separation was achieved using n-heptane-extraction-assisted pyrolysis. This provides a new method for the component analysis of oily sludge and promotes its efficient separation. [ABSTRACT FROM AUTHOR]

In order to ensure that emergency materials can be transported to the material demand points in the shortest time within the golden rescue time after emergencies, and to ensure the fairness of material distribution, a bi-level optimal scheduling model of emergency materials considering multimodal transport is constructed in this paper. The upper model takes the shortest transportation time as the objective function by considering multimodal transport. The lower model takes the minimum variance of emergency material distribution at each material demand point as the objective function by considering the fairness of emergency material distribution. The improved genetic algorithm is used to solve the bi-level optimal model. Compared with the classical genetic algorithm, the improved genetic algorithm is found to be effective. Finally, a case study is conducted to verify the rationality of the model. The results show that the emergency materials can be transported to the material demand points in the shortest possible time according to the requirements of decision-makers through this model. Besides, the fairness of emergency material distribution can be guaranteed and can provide further emergency decision-making reference for decision-makers. [ABSTRACT FROM AUTHOR]

A train of subsurface mesoscale eddies (SMEs) consisting of two cyclones and two anticyclones was observed in the northeastern South China Sea (NESCS) in 2015 by a mooring array. In contrast to the widely reported surface-intensified eddies, the SMEs had weak surface signals but showed maximum velocity at ∼370 m with a magnitude of 17.2 cm s-1. The SMEs generally propagated westward with a speed of ∼4.3 cm s-1, which resulted in a distinct ∼120-dayperiod oscillations in the moored time series. Based on the concurrent velocity, temperature, and salinity from the mooring array, three-dimensional structures of the SMEs were constructed, which were then used to quantify water mass transports induced by them. The results revealed that all these SMEs were vertically tilted with an influence depth exceeding 1000 m. Water mass analysis suggested that the cyclonic and anticyclonic SMEs trapped the northwest Pacific water and the NESCS local water, respectively. The cyclones transported 1.00 ± 0.25 Sv (1 Sv ≡ 106 m³ s-1) North Pacific Intermediate Water westward into the NESCS during the 2-yr observation period, accounting for 61.7% of the observed volume transport through the Luzon Strait between 25.8 and 27.4s0. Furthermore, it also showed that both the trapping and stirring effects of the SMEs induced an eastward heat transport across the Luzon Strait, but the role of the former was much more important than the latter. The present results suggested that the SMEs near the Luzon Strait may provide a novel route for the intermediate-layer water exchange between the NESCS and Pacific. [ABSTRACT FROM AUTHOR]

In biology, biogeography, ecology, and conservation, species identification is critical. Hesperis L. is a Brassicaceae (Cruciferae) genus of 46 species found across the temperate northern hemisphere, from South and Central Europe to Southwest Asia, Caucasia, and the mountainous portions of West China and Mongolia. According to the latest therapies, Hesperis is expressed in Iran by six species. Despite the fact that several Hesperis species are widely distributed throughout Iran, nothing is known about their genetic diversity, divergence techniques, or dispersion patterns. As a result, we examined 122 accessions from six Hesperis species gathered from various locations in Iran using genetic (ISSR markers) and morphological techniques. A total of ten ISSR markers were employed in this study. The Nei's genetic distance was used to measure genetic distances, and descriptive statistics of folks were used to produce genetic parameters. There were a total of 118 polymorphic bands found. The study's aims are as follows: 1) Is it possible to identify Hesperis species using ISSR markers? 2) In Iran, what is the genetic make-up of these taxa? 3) How do interspecies relationships work? According to the conclusions of this research, morphological and ISSR data may be utilized to identify species. The Hesperis species are genetically distinct yet share significant genes, according to the AMOVA and STRUCTURE analyses. [ABSTRACT FROM AUTHOR]

Anti-Müllerian hormone (Amh) plays an important role in gonadal function. Amh deficiency causes severe gonadal dysgenesis and dysfunction in zebrafish, with gonadal hypertrophy in both sexes. However, its mechanism of action remains unknown. Intriguingly, the Amh cognate type II receptor (Amhr2) is missing in the zebrafish genome, in sharp contrast to other species. Using a series of zebrafish mutants (amh, fshb, fshr and lhcgr), we provided unequivocal evidence for actions of Amh, via modulation of gonadotropin signaling, on both germ cell proliferation and differentiation. The gonadal hypertrophy in amh mutants was abolished in the absence of Fshr in females or Fshr/ Lhcgr in males. Furthermore,we demonstrated that knockout of bmpr2a, but not bmpr2b, phenocopied all phenotypes of the amh mutant in both sexes, including gonadal hypertrophy, hyperproliferation of germ cells, retarded gametogenesis and reduced fshb expression. In summary, the present study provided comprehensive genetic evidence for an intimate interaction of gonadotropin and Amh pathways in gonadal homeostasis and gametogenesis and for Bmpr2a as the possible missing link for Amh signaling in zebrafish. [ABSTRACT FROM AUTHOR]

Based on long-term mooring-array and satellite observations, three-dimensional structure and interannual variability of the Kuroshio Loop Current (KLC) in the northeastern South China Sea (SCS) were investigated. The 3-yr moored data between 2014 and 2017 revealed that the KLC mainly occurred in winter and it exhibited significant interannual variability with moderate, weak, and strong strengths in the winters of 2014/15, 2015/16, and 2016/17, respectively. Spatially, the KLC structure was initially confined to the upper 500m near the Luzon Strait, but it became more barotropic, with kinetic energy transferring from the baroclinic mode to the barotropic mode when it extended into the SCS interior. Through analyzing the historical altimeter data between 1993 and 2019, it is found that the KLC event in 2016/17 winter is the strongest one since 1993. Moored-data-based energetics analysis suggested that the growth of this KLC event was primarily fed by the strong wind work associated with the strengthened northeast monsoon in that La Niña-year winter. By examining all of the historical KLC events, it is found that the strength of KLC is significantly modulated by El Niño-Southern Oscillation, being stronger in La Niña and weaker in El Niño years. This interannual modulation could be explained by the strengthened (weakened) northeast monsoon associated with the anomalous atmospheric cyclone (anticyclone) in the western North Pacific during La Niña (El Niño) years, which inputs more (less) energy and negative vorticity southwest of Taiwan that is favorable (unfavorable) for the development of KLC. [ABSTRACT FROM AUTHOR]

An activity-based enzyme activity screening system identified gut microbial DPP4 isozymes that can decrease active GLP-1 but cannot be inhibited by sitagliptin. Gut microbial DPP4 isozyme can impair host glucose homeostasis, and variations in microbial DPP4 activities could possibly contribute to the heterogeneous responses to sitagliptin observed among patients with T2D. INTRODUCTION: Gut microbiota can regulate the physiology and pathophysiology of the host by producing enzymes with functions similar to those of the host. [Extracted from the article]

This work investigates the performance of a cantilevered piezoelectric energy harvester (PEH) for harvesting energy from bridge vibrations induced by moving vehicles. The bridge is simplified as a simply supported beam. Three models have been considered for modeling the vehicle moving on the bridge, namely a moving load, a moving mass, and a moving oscillator. The influence of surface unevenness on the energy harvested by the PEH has been taken into account. A comprehensive parametric study is conducted to show the effect of the PEH installation position, vehicle speed, and configuration of the PEH on the harvested energy. The results indicate that the difference in harvested energy calculated by various vehicle models is less than 10% if surface unevenness of the bridge is ignored. If surface unevenness is considered, more energy can be harvested. However, the maximum accumulated energy calculated using the moving oscillator model is less than 5% of that predicted by the moving mass model. The unevenness effect is not applicable in the moving load model. [ABSTRACT FROM AUTHOR]

Homology-directed recombination (HDR)-mediated genome editing is a powerful approach for both basic functional study and disease modeling. Although some studies have reported HDR-mediated precise editing in nonrodent models, the efficiency of establishing pure mutant animal lines that carry specific amino acid substitutions remains low. Furthermore, because the efficiency of nonhomologous end joining (NHEJ)- induced insertion and deletion (indel) mutations is normally much higher than that of HDR-induced point mutations, it is often difficult to identify the latter in the background of indel mutations. Using zebrafish as the model organism and Y box- binding protein 1 (Ybx1/ybx1) as the model molecule, we have established an efficient platform for precise CRISPR/Cas9-mediated gene editing in somatic cells, yielding an efficiency of up to 74% embryos. Moreover, we established a procedure for screening germline transmission of point mutations out of indel mutations even when germline transmission efficiency was low (<2%). To further improve germline transmission of HDR-induced point mutations, we optimized several key factors that may affect HDR efficiency, including the type of DNA donor, suppression of NHEJ, stimulation of HDR pathways, and use of Cas9 protein instead of mRNA. The optimized combination of these factors significantly increased the efficiency of germline transmission of point mutation up to 25%. In summary, we have developed an efficient procedure for creating point mutations and differentiating mutant individuals from those carrying knockouts of entire genes. [ABSTRACT FROM AUTHOR]

In this paper, comparison between back-illuminated p-i-n AlGaN-based ultraviolet photodetectors (UV-PDs) with and without an n-AlGaN inserted layer is carried out. The results show that the introduction of n-AlGaN interlayer significantly reduces the dark current of AlGaN-based UV-PDs. The mechanism involved is clarified and can be attributed to the role of n-AlGaN interlayer which depletes to isolate the leakage paths generated by dislocations of AlGaN material. Besides, it also greatly improves the spectral performances of the p-i-n AlGaN-based UV-PDs, which can be related to the additional built-in electric fields introduced by n-AlGaN inserted layer that contribute to separate and transport the photon-generated carriers. [ABSTRACT FROM AUTHOR]

In order to unambiguously identify the source of magnetism reported in recent studies of the Co-Te system, two sets of high-quality, epitaxial CoTex films (thickness ≈ 300 nm) were prepared by pulse laser deposition (PLD). X-ray diffraction (XRD) shows that all of the films are epitaxial along the [001] direction and have the hexagonal NiAs structure. There is no indication of any second phase metallic Co peaks (either fcc or hcp) in the XRD patterns. The two sets of CoTex films were grown on various substrates with PLD targets having Co:Te in the atomic ratio of 50:50 and 35:65. From the measured lattice parameters c = 5.396 Å for the former and c = 5.402 Å for the latter, the compositions CoTe1.71 (63.1% Te) and CoTe1.76 (63.8% Te), respectively, are assigned to the principal phase. Although XRD shows no trace of metallic Co second phase, the magnetic measurements do show a ferromagnetic contribution for both sets of films with the saturation magnetization values for the CoTe1.71 films being approximately four times the values for the CoTe1.76 films. 59Co spin-echo nuclear magnetic resonance (NMR) clearly shows the existence of metallic Co inclusions in the films. The source of weak ferromagnetism reported in several recent studies is due to the presence of metallic Co, since the stoichiometric composition “CoTe” does not exist. [ABSTRACT FROM AUTHOR]

In recent years, study concerning activity inhibitors of prostate-specific membrane antigen (PSMA) has been concentrated on the glutamic urea (Glu-urea-R) small molecule and its analogs. The present study aimed to synthesize 4 analogs of Glu-urea-R and identify the affinities of these compounds to PSMA. The compounds were synthesized from raw materials, and the experimental procedures of the present study were in accordance with standard techniques under anhydrous and anaerobic conditions. Glu-urea-Lysine (Glu-urea-Lys), Glu-urea-Ornithine (Glu-urea-Orn), Glu-urea-Glutamine (Glu-urea-Gln) and Glu-urea-Asparagine (Glu-urea-Asn) were successfully synthesized, and their structures were confirmed to be as desired using nuclear magnetic resonance spectroscopy and mass spectrometry. An affinity assay was performed to detect the affinity between the various compounds and PSMA expressed from the prostate cancer LNCap cell line. Glu-urea-Gln had the highest affinity to PSMA, followed by Glu-urea-Asn, Glu-urea-Orn and Glu-urea-Lys. In conclusion, the present study demonstrated that Glu-urea-R specifically binds PSMA expressed in the LNCap cell line and inhibits its activity. [ABSTRACT FROM AUTHOR]

Cross-linked hyaluronic acid hydrogel (cHA gel) and dexamethasone (Dex) have been used to treat knee osteoarthritis (OA) in clinical practice owing to their chondroprotective and anti-inflammatory effects, respectively. The aim of the present study was to compare the treatment effects of the cHA gel pre-mixed with/without Dex in a surgery-induced osteoarthritis model in rats. Anterior cruciate ligament transection (ACLT) surgery was performed on the right knee of rats to induce OA. Male 2-month-old Sprague-Dawley rats were randomly divided into five groups (n = 10/per group): (1) ACLT + saline; (2) ACLT + cHA gel; (3) ACLT + cHA-Dex (0.2 mg/mL) gel; (4) ACLT + cHA-Dex (0.5 mg/mL) gel; (5) Sham + saline. Intra-joint injections were performed four weeks after ACLT in the right knee. All animals were euthanized at 12 weeks post-surgery. Cartilage damage and changes in the synovial membrane were assessed by micro X-ray, Indian ink articular surface staining, Safranin-O/Fast Green staining, immunohistochemistry, hematoxylin and eosin staining of the synovial membrane, and quantitative reverse transcription-polymerase chain reaction for changes in gene expression. Micro X-ray revealed that the knee joint treated with the cHA-Dex gel was wider than those treated with cHA gel alone or saline. The cHA-Dex gel group had less Indian ink staining (indicator of cartilage fibrillation) than the cHA gel or saline injection groups. Safranin-O/Fast Green staining indicated that increased proteoglycan staining and less cartilage damage were found in the cHA-Dex gel group compared with the cHA gel or saline injection groups. Quantification of histology findings from saline, cHA gel, cHA-Dex (0.2 mg/mL) gel, cHA-Dex (0.5 mg/mL) gel, and sham groups were 5.84 ± 0.29, 4.50 ± 0.87, 3.00 ± 1.00, 2.00 ± 0.48, and 0.30 ± 0.58 (p < 0.05), respectively. A strong staining of type II collagen was found in both the cHA-Dex gel groups compared with saline group or cHA alone group. Similar result was found for the mRNA level of aggrecan and opposite result for type X collagen. Hematoxylin and eosin staining in the synovial membrane showed less synovial lining cell layers and reduced inflammatory cell infiltration in cHA-Dex gel-treated animals compared with saline or cHA only groups. Altogether, cHA-Dex gel has better chondroprotective and anti-inflammatory effects in rat surgery-induced osteoarthritis than cHA alone. [ABSTRACT FROM AUTHOR]

This paper presents the design and analysis of fractional slot multilayer interior permanent magnet synchronous machines (PMSMs) with concentrated winding for electric vehicles applications. The major advantages of concentrated winding will be analyzed first. The significant design consideration of multilayer interior permanent magnet machines will be illustrated, as well. Finally, the advanced finite element method will be employed to verify the detailed electromagnetic performance of the proposed interior PMSMs. [ABSTRACT FROM AUTHOR]

In recent years, single-photon emission computed tomography and positron emission tomography (PET) have also been used, in addition to computed tomography and magnetic resonance imaging, in targeting the diagnosis of prostate cancer. The aim of this study was to synthesize the prostate-specific membrane antigen (PSMA)-based imaging agent 2-{3-[1-Carboxy-5-(4-[18F] fluoro-benzoylamino)-pent yl]-ureido}-pentanedioic acid (18F-Glu-Urea-Lys, [18F] and to detect its PET imaging efficiency for high PSMA expression in prostate cancer. In this study, 18F-Glu-Urea-Lys was synthesized in two steps from the p-methoxybenzyl-protected Glu-Urea-Lys precursor using N-Hydroxysuccinimidyl-4-[18F] fluorobenzoate ([18F]SFB). PET imaging evaluation was conducted in nude mice using LNCaP (PSMA+), and PC-3, 231 and A549 (all PSMA-) xenograft models. The results indicated that 18F-Glu-Urea-Lys was produced in radiochemical yields of 28.7%. The radiochemical purity was 99.1% and the mean total synthesis time was 168 min. In nude mice models 18F-Glu-Urea-Lys clearly delineated PSMA+ LNCaP prostate tumor xenografts on PET imaging. At 4 h post-injection, the contrast agents were only observed in renal, liver, bladder and PSMA+ LNCaP tumors. The PSMA- tumor (PC-3, 231 and A549) was clear. In conclusion, 18F-Glu-Urea-Lys was found to be easily synthesized. This radiotracer demonstrated high tumor and low-to-normal tissue uptake, fast clearance from non-target tissues and retention in PSMA+ prostate tumor xenografts. [ABSTRACT FROM AUTHOR]

In order to optimize linear algebra transition systems, a kind of hybrid system, approximate equivalence semantics for linear algebra transition systems is proposed. The semantics is called approximation ready trace semantics. The work is based on the ready trace semantics for concrete process algebra and numerical approximate calculation theory in algebra. The advantage of the work is that it makes the traditional formal verification theory can be applied to verification of the linear algebraic transition system. Then the approximate ready-trace semantics axiom system, which can be used to reasoning of linear algebraic transition system, is put forward. Finally, the advantage of approximate ready trace semantics is verified through a traffic lights control vehicle flow system example. [ABSTRACT FROM AUTHOR]

The CHADS2 score is a validated clinical tool used for the risk stratification of stroke in the presence of atrial fibrillation (AF). Recently, some studies have shown that CHADS2 score may predict the risk of AF, which yielded conflicting results. The purpose of this study is to perform a meta-analysis of observational studies to examine the association between the CHADS2 score and risk of AF. Using PubMed and EMBASE database, we searched published articles by November 2014 to identify studies that evaluated the association between CHADS2 score and the risk of AF. We used both fixed-effects and random-effects models to calculate the overall effect estimate. A sensitivity analysis and subgroup analysis were performed to find the origin of heterogeneity. Of the 1,806 studies identified initially, 19 studies were included into our analysis, with a total of 714,672 patients. The CHADS2 score was found to be an independent predictor of AF as both a continuous variable (odds ratio 1.43, 95% confidence interval 1.10 to 1.86, p = 0.007) and categorical variable (odds ratio 3.37, 95% confidence interval 2.65 to 4.28, p <0.00001). Subgroup analysis revealed that different patients' age in study population may be a possible reason for the significant heterogeneity in our meta-analysis. In conclusion, CHADS2 score predicts the risk of AF. Addressing risk factors and early recognition of AF are important and also awareness of CHADS2 score to reduce stroke risk with pharmacologic prophylaxis. [ABSTRACT FROM AUTHOR]

Expression of the nodal gene is high in a number of tumor cell types and may promote tumor growth. The expression of lefty, an inhibitor of nodal is often reduced in tumor cells. To the best of our knowledge, few studies have investigated the expression of nodal and lefty in renal cell carcinoma (RCC) cells. In the present study, quantitative polymerase chain reaction assays demonstrated that the level of nodal expression in RCC cells was high compared with that of adjacent non-tumor tissue cells, while the opposite pattern was observed for the level of lefty expression. Furthermore, lefty overexpression in RCC cells inhibited the expression of nodal. Nodal overexpression promoted RCC cell proliferation and invasion, and inhibited RCC cell apoptosis. Nodal downregulation and lefty overexpression led to similar observations: The inhibition of RCC cell proliferation and invasion, and the promotion of RCC cell apoptosis. The results of the present study suggested that the expression of nodal promoted RCC growth by activating the smad and extracellular signal-regulated kinases 1/2 pathways. The expression of lefty in RCC cells was lower than that in adjacent non-tumor cells, which may result in the overexpression of nodal, thereby promoting the growth of RCC. The results of the present study may therefore be useful for the development of novel biomarkers for RCC tumor diagnosis, and suggest a potential target gene for the treatment of RCC. [ABSTRACT FROM AUTHOR]

Background In patients with chronic severe aortic regurgitation (AR), aortic valve replacement (AVR) has been proved to promote left ventricular (LV) remodeling, especially LV end-diastolic dimension (LVEDD) reduction. However, there is little research whether postoperative LVEDD could return to normal parameter after AVR. The objective of this study was to determine predictors for the recovery of dilated LVEDD early after AVR. Methods The echocardiographic data of 105 patients, who underwent AVR for chronic pure AR between January 2005 and December 2011, were analyzed at the preoperative (3-7 d), early (6-8 mo), and late (2-y) postoperative stages, retrospectively. According to the baseline level, LVEDD >70 mm or LV end-systolic dimension (LVESD) >50 mm or LVESD index >25 mm/m² were defined as severe LV dilation. Patients were then categorized into two groups (group 1: severe LV dilation; group 2: nonsevere LV dilation). Results In all patients, four-fifth of the reduction in LV dimension occurred at early (6-8 mo) postoperative stage. The patients in both groups had significant decreases in the LVEDD and LVESD early after AVR, with an additional but insignificant reduction at late postoperative stage. The ejection fraction (EF) in both groups significantly increased at either early or late stage. However, the LVEDD and LVESD in group 1 were larger than those in group 2, and the EF in group 1 was lower than that in group 2 at early postoperative stage. By multivariate analysis, we found that the preoperative EF was a good predictor for the recovery of dilated LVEDD early after AVR (P = 0.009). Receiver-operating characteristics analysis showed that EF >52% was the best cut-off value for the recovery of LVEDD. Conclusions In patients with chronic pure AR, preoperative EF may be a good predictor for successful recovery of dilated LVEDD early after AVR. [ABSTRACT FROM AUTHOR]

Arrhythmogenic cardiomyopathy (AC) is associated with mutations in genes encoding intercalated disc proteins and ultimately results in sudden cardiac death. A subset of patients with AC have the autosomal recessive cardiocutaneous disorder Naxos disease, which is caused by a 2-base pair deletion in the plakoglobin-encoding gene JUP that results in a truncated protein with reduced expression. In mice, cardiomyocyte-specific plakoglobin deficiency recapitulates many aspects of human AC, and overexpression of the truncated Naxos-associated plakoglobin also results in an AC-like phenotype; therefore, it is unclear whether Naxos disease results from loss or gain of function consequent to the plakoglobin mutation. Here, we generated 2 knockin mouse models in which endogenous Jup was engineered to express the Naxos-associated form of plakoglobin. In one model, Naxos plakoglobin bypassed the nonsense-mediated mRNA decay pathway, resulting in normal levels of the truncated plakoglobin. Moreover, restoration of Naxos plakoglobin to WT levels resulted in normal heart function. Together, these data indicate that a gain of function in the truncated form of the protein does not underlie the clinical phenotype of patients with Naxos disease and instead suggest that insufficiency of the truncated Naxos plakoglobin accounts for disease manifestation. Moreover, these results suggest that increasing levels of truncated or WT plakoglobin has potential as a therapeutic approach to Naxos disease. [ABSTRACT FROM AUTHOR]

Background Directional selection for growth has resulted in the 9-10th generation of domesticated Atlantic salmon Salmo salar L. outgrowing wild salmon by a ratio of approximately 3:1 when reared under standard hatchery conditions. In the wild however, growth of domesticated and wild salmon is more similar, and seems to differ at the most by a ratio of 1.25:1. Comparative studies of quantitative traits in farmed and wild salmon are often performed by the use of common-garden experiments where salmon of all origins are reared together to avoid origin-specific environmental differences. As social interaction may influence growth, the large observed difference in growth between wild and domesticated salmon in the hatchery may not be entirely genetically based, but inflated by inter-strain competition. This study had two primary aims: (i) investigate the effect of social interaction and inter-strain competition in common-garden experiments, by comparing the relative growth of farmed, hybrid and wild salmon when reared together and separately; (ii) investigate the competitive balance between wild and farmed salmon by comparing their norm of reaction for survival and growth along an environmental gradient ranging from standard hatchery conditions to a semi-natural environment with restricted feed. Results The main results of this study, which are based upon the analysis of more than 6000 juvenile salmon, can be summarised as; (i) there was no difference in relative growth between wild and farmed salmon when reared together and separately; (ii) the relative difference in body weight at termination between wild and farmed salmon decreased as mortality increased along the environmental gradient approaching natural conditions. Conclusions This study demonstrates that potential social interactions between wild and farmed salmon when reared communally are not likely to cause an overestimation of the genetic growth differences between them. Therefore, common-garden experiments represent a valid methodological approach to investigate genetic differences between wild and farmed salmon. As growth of surviving salmon of all origins became more similar as mortality increased along the environmental gradient approaching natural conditions, a hypothesis is presented suggesting that size-selective mortality is a possible factor reducing growth differences between these groups in the wild. [ABSTRACT FROM AUTHOR]

This paper is aimed to analyze the current situation and problems about use of various karst environments via filed survey, documentation and comparison methods, and to make reasonable recommendations about land use and management for different karst types in a bid to provide theoretical and practical basis for optimization of karst land use and the comprehensive control of karst rock desertification. The results show that, ① as the bare karst areas are lack of water and soil and highly prone to droughts and floods, land utilization in such areas should follow the principle of soil and water conservation and ecological restoration, emphasize both the ecological benefit and the economic benefit and reasonably configure the land resources to achieve the virtuous circle; ②in covered karst areas, the most important task is to take measures to prevent the appearance of secondary kast rock desertification, water exhaustion and karst collapse; ③ the buried karst areas shall mainly focus on prevention of overlaying sand shale collapse, and possible pollution of deep karst water and the surface land resulted from exploration and exploitation of oil and gas and geothermal water. ④ The final conclusion is that features and problems of land utilization of the three karst types are different from each other, and that the general principle for land use in karst regions shall be based on the local conditions. [ABSTRACT FROM AUTHOR]

It has become increasingly common in epidemiological studies to pool specimens across subjects to achieve accurate quantitation of biomarkers and certain environmental chemicals. In this article, we consider the problem of fitting a binary regression model when an important exposure is subject to pooling. We take a regression calibration approach and derive several methods, including plug-in methods that use a pooled measurement and other covariate information to predict the exposure level of an individual subject, and normality-based methods that make further adjustments by assuming normality of calibration errors. Within each class we propose two ways to perform the calibration (covariate augmentation and imputation). These methods are shown in simulation experiments to effectively reduce the bias associated with the naive method that simply substitutes a pooled measurement for all individual measurements in the pool. In particular, the normality-based imputation method performs reasonably well in a variety of settings, even under skewed distributions of calibration errors. The methods are illustrated using data from the Collaborative Perinatal Project. [ABSTRACT FROM AUTHOR]

According to the law of likelihood, statistical evidence is represented by likelihood functions and its strength measured by likelihood ratios. This point of view has led to a likelihood paradigm for interpreting statistical evidence, which carefully distinguishes evidence about a parameter from error probabilities and personal belief. Like other paradigms of statistics, the likelihood paradigm faces challenges when data are observed incompletely, due to non-response or censoring, for instance. Standard methods to generate likelihood functions in such circumstances generally require assumptions about the mechanism that governs the incomplete observation of data, assumptions that usually rely on external information and cannot be validated with the observed data. Without reliable external information, the use of untestable assumptions driven by convenience could potentially compromise the interpretability of the resulting likelihood as an objective representation of the observed evidence. This paper proposes a profile likelihood approach for representing and interpreting statistical evidence with incomplete data without imposing untestable assumptions. The proposed approach is based on partial identification and is illustrated with several statistical problems involving missing data or censored data. Numerical examples based on real data are presented to demonstrate the feasibility of the approach. [ABSTRACT FROM AUTHOR]

A nano-structured TiN/Ti coating with a total thickness of 0.9 μm was deposited on nitinol cardiac occluders using the filtered multi-arc vacuum ion plating technique at less than 300°C. The coating was composed of laminated TiN/Ti layers with thickness of about 100 nm. The cardiac occluders made of a nitinol mesh with and without a graded nano-structured titanium nitride (TiN) coating were implanted into the hearts of rams. The nickel concentration of the whole blood of the animals were measured one week, one month, three months, and six months after implantation and compared to that before operation. The nickel concentration in the neo-endocardium covered occluders was also measured using graphite furnace atomic absorption spectrophotometry. After one week, the nickel content in the blood increased by a factor of three compared to the level before operation and decreased afterwards returning to the normal level after six months when endothelialization was complete. Statistical analyses showed that the TiN coating could mitigate nickel release into blood (P<0.01). For example, the nickel concentration released from the control increased from about 2.65±1.20 μg/kg, the normal concentration, to 7.30±1.00 μg/kg but just from 2.56±1.16 μg/kg to 4.68±1.29 μg/kg from the TiN coated occluder after 7 days. The nickel concentration in the neo-endocardium covered and TiN coated occluders reached 17.0±8.05 μg/kg in two months after implantation. In comparison, it was 31.0±5.72 μg/kg for the occluder without the TiN coating. While normal concentration of nickel in endocardium is also 2.6±1.09 μg/kg. Our results demonstrate that the graded TiN coating can significantly reduce nickel release into the endocardium (P<0.01) under in vivo conditions. [ABSTRACT FROM AUTHOR]

The authors investigated the relationship between patients' self- rated satisfaction with treatment services during and shortly after treatment with their drug use outcomes at one year follow-up, using a US national panel survey of patients in 62 methadone, outpatient, short- term residential, and long-term residential programs. A favorable evaluation of treatment near the time of discharge had a significant positive relationship with drug use improvement outcomes approximately one year later, independent of the separately measured effects of treatment duration, counseling intensity, patient adherence to treatment protocols, pre-treatment drug use patterns, and other characteristics of patients and treatment programs. [ABSTRACT FROM AUTHOR]

In this study, we develop a facile and efficient method for period-decorating carbon nanotubes (CNTs) using a supercritical (SC) CO 2antisolvent-induced polymer epitaxy (SAIPE) method. It helps the epitaxy growth of PE on CNTs under a series of suitable experimental conditions, forming a nanohybrid shish-kebab (NHSK) structure. With the variation of a series of experimental conditions or peripheral effect, such as different solvent, PE concentration, CNTs concentration and SC CO 2pressure, the NHSK structure, i.e., the size of the lamellae and the interval between them along the stem, can be varied. When p-xylene was used as the solvent for PE and single-walled CNT (SWCNT), the size of the lamellae can be adjusted from 80−120 to 125−250 nm with the change of the PE concentration. Using the same solvent p-xylene, with the change of SC CO 2pressure, the size of the lamellae can be changed from 125−250 to 300−400 nm. When dichlorobenzene (DCB) was used as the solvent for PE and SWCNT, with the increase of the SWCNT concentration, from 0.002 to 0.006 and 0.01 wt %, the size of the lamellae can be reduced from 305−420 to 280−400 and 85−200 nm. In comparison to the experimental result with p-xylene used as the solvent, it is found that the decorated CNTs have more excellent dispersion when DCB was used as the solvent. Our experimental results indicate that the SAIPE method is effective for both SWCNTs and multiwalled CNTs (MWCNTs). Therefore, this work not only provides a new route to periodically functionalize CNTs with a controllable and adjustable method, but also it can be anticipated to open a gateway for making use of peculiar properties of SC CO 2to help functionalize CNTs in an environmentally benign manner. [ABSTRACT FROM AUTHOR]

Regression analysis is often challenged by the fact that some covariates are not completely observed. Among other approaches is a newly developed semiparametric maximum likelihood (SML) method that requires no parametric specification of the selection mechanism or the covariate distribution and that yields efficient inference, at least in some specific models. In this paper, we propose an EM algorithm for finding the SML estimate and for variance estimation. Simulation results suggest that the SML method performs reasonably well in moderate-sized samples. In contrast, the analogous parametric maximum likelihood method is subject to severe bias under model mis-specification, even in large samples. [ABSTRACT FROM AUTHOR]

This study uses detailed information from the Department of Labor (O'NET 98) concerning the characteristics and content of 1,122 occupations, and combines these data with information on alcohol and drug use collected by the Substance Abuse and Mental Health Services Administration in their 1997 National Household Survey on Drug Abuse (NHSDA). Using a merged data set, based on 7,477 full-time workers, weighted logistic regression analyses were used to examine the relationships between eight occupational and job dimensions and workers' current and prior use of alcohol and drugs. Results show that steady employment or job security has the most pronounced negative effect on alcohol and drug use, while characteristics such as the pace of activity, job independence, and skills utilization to include feelings of accomplishment have little or no effect on employees' alcohol and drug use. Furthermore, the etiology of cocaine use appears quite different from that of alcohol and other types of drug use: all else being equal, employees' odds of using cocaine, when working in an occupation with greater job variety, decrease by 64 percent. However, employees in occupations with greater job autonomy are about 4 times more likely to use cocaine than are employees in jobs with less autonomy. These findings suggest that occupational conditions have a discernible influence on alcohol and drug use among employees, albeit in more complex ways than those suggested by much of the organizational stress and occupational subcultural literature. [ABSTRACT FROM AUTHOR]

Triosephosphate isomerase (TPI) is an enzyme that functions in plant energy production, accumulation, and conversion. To understand its function in maize, we characterized a maize TPI mutant, zmtpi4. In comparison to the wild type, zmtpi4 mutants showed altered ear development, reduced kernel weight and starch content, modified starch granule morphology, and altered amylose and amylopectin content. Protein, ATP, and pyruvate contents were reduced, indicating ZmTPI4 was involved in glycolysis. Although subcellular localization confirmed ZmTPI4 as a cytosolic rather than a plastid isoform of TPI, the zmtpi4 mutant showed reduced leaf size and chlorophyll content. Overexpression of ZmTPI4 in Arabidopsis led to enlarged leaves and increased seed weight, suggesting a positive regulatory role of ZmTPI4 in kernel weight and starch content. We conclude that ZmTPI4 functions in maize kernel development, starch synthesis, glycolysis, and photosynthesis. [ABSTRACT FROM AUTHOR]

Aims: Multiple genes and environmental factors are known to be involved in congenital heart disease (CHD), but epigenetic variation has received little attention. Monozygotic (MZ) twins with CHD provide a unique model for exploring this phenomenon. In order to investigate the potential role of Deoxyribonucleic Acid (DNA) methylation in CHD pathogenesis, the present study examined DNA methylation variation in MZ twins discordant for CHD, especially ventricular septal defect (VSD). Methods and Results: Using genome-wide DNA methylation profiles, we identified 4004 differentially methylated regions (DMRs) in 18 MZ twin pairs discordant for CHD, and 2826 genes were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed a list of CHD-associated pathways. To further investigate the role of DNA methylation in VSD, data from 7 pairs of MZ twins with VSD were analyzed. We identified 1614 DMRs corresponding to 1443 genes associated with arrhythmogenic right ventricular cardiomyopathy, cyclic guanosine monophosphate-protein kinase G (cGMP-PKG) signaling pathway by KEGG analysis, and cell-cell adhesion, calcium ion transmembrane transport by GO analysis. A proportion of DMR-associated genes were involved in calcium signaling pathways. The methylation changes of calcium signaling genes might be related to VSD pathogenesis. Conclusion: CHD is associated with differential DNA methylation in MZ twins. CHD may be etiologically linked to DNA methylation, and methylation of calcium signaling genes may be involved in the development of VSD. [ABSTRACT FROM AUTHOR]

In this Letter, we report a resonant x-ray scattering measurement of stripelike charge order in the 1/8th doped component of electronically phase-separated, orthorhombic La2CuO4+y. This observation is coupled to the absence of any resonant (001) peak, which at different resonant energies has been identified with the presence of low-temperature-tetragonal-like structural tilt patterns or nematicity in the CuO planes. Thus, we provide evidence that structural pinning is not necessary for the formation of static charge stripes and that the relationship between charge nematicity and stripes may not be simple. [ABSTRACT FROM AUTHOR]

Objective • To analyze the enrichment pathway, hub gene, and Protein-protein interaction (PPI) network of rheumatoid arthritis (RA) and construct peripheral blood subtypes based on integrated bioinformatics analysis. Methods • Suitable datasets were screened from the GEO database based on titles and abstracts, batch positive analysis was performed using R language, and KEGG enrichment analysis and GO enrichment analysis were performed. After screening the differential genes, the PPI network was constructed, and the hubba plug-in of Cytoscape software was used to obtain the top 10 hub genes(key regulatory genes). hub genes were used as the typing condition to identify the molecular subtypes of synovial tissue and peripheral blood of arthritis. Results • GSE12021 and GSE93272 have been chosen for analysis. GSE12021 presents the transcriptome analysis of human joint synovial tissue, comprising 12 samples from patients with rheumatoid arthritis and 9 samples from normal healthy individuals. On the other hand, GSE93272 includes human peripheral blood samples, comprising 232 samples from patients with rheumatoid arthritis and 43 samples from normal healthy individuals. The main results of GSE12021 KEGG enrichment were Parathyroid hormone synthesis, Relaxin signaling pathway, TNF signaling pathway, Rheumatoid arthritis, T cell receptor signaling pathway, Th1 and Th2 cell differentiation, Th17 cell differentiation, Toll−like receptor signaling pathway and so on. The main results of GSE12021 GO enrichment were regulation of feeding behavior, regulation of neuron death, positive regulation of cell−cell adhesion, and positive regulation of leukocyte activation. The top 10 hub genes were CD8A, JUN, CTLA4, CD19, LCK, FOS, CCL5, IL7R, CCR7 and CD247. Synovial tissue and peripheral blood subtypes of rheumatoid arthritis showed that the two classification methods maintained consistency. Conclusion • Identifying the Hub gene in peripheral blood helps screen molecular subtypes of rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Maintenance of genomic diversity is critically dependent on gene regulation at the transcriptional level. This occurs via the interaction of regulatory DNA sequence motifs with DNA-binding transcription factors. The zinc finger, BED-type (ZBED) gene family contains major DNA-binding motifs present in human transcriptional factors. It encodes proteins that present markedly diverse regulatory functions. ZBED1 has similar structural and functional properties to its Drosophila homolog DNA replication-related element-binding factor (DREF) and plays a critical role in the regulation of transcription. ZBED1 regulates the expression of several genes associated with cell proliferation, including cell cycle regulation, chromatin remodeling and protein metabolism, and some genes associated with apoptosis and differentiation. In the present review, the origin, structure and functional role of ZBED1 were comprehensively assessed. In addition, the similarities and differences between ZBED1 and its Drosophila homolog DREF were highlighted, and future research directions, particularly in the area of clinical cancer, were discussed. [ABSTRACT FROM AUTHOR]

Foreign body detection is an important aspect that affects the quality of tobacco production. This paper describes a direct foreign body detection scheme using machine vision, which uses three cameras arranged around a tobacco bale to record its multiple surfaces and directly identify foreign bodies. In this study, color sorting table method (CSTM) was first used to identify and remove color-sensitive foreign bodies; thereafter, gray threshold method and double threshold method were used to further identify and remove foreign bodies with similar colors. The experimental results indicate that the multi-step hybrid identification method proposed herein can effectively identify and remove various foreign bodies in the production process of tobacco packs, with an accuracy rate of 97.8%, which meets the industrial requirements for foreign body detection. Compared with various existing devices and methods, it has the advantages of high detection efficiency and low cost. [ABSTRACT FROM AUTHOR]

Sex determination and differentiation are complex processes controlled by many different factors; however, the relationships among these factors are poorly understood. Zebrafish gonadal differentiation exhibits high plasticity involving multiple factors and pathways, which provides an excellent model for investigating the interactions between them. Ovarian aromatase (cyp19a1a) and dmrt1 are key factors in directing vertebrate ovary and testis differentiation, respectively. Knockout of zebrafish cyp19a1a leads to all-male offspring, whereas the loss of dmrt1 results in a femalebiased sex ratio. In the present study, we established dmrt1-/-; cyp19a1a-/- double mutant zebrafish and discovered that the introduction of the dmrt1 mutation into the cyp19a1a mutant could rescue the all-male phenotype of the latter. Interestingly, despite the lack of aromatase/estrogens, the follicles in the ovary of the rescued cyp19a1a mutant could develop normally up to the previtellogenic stage. Further evidence suggested the ovarian aromatase directed ovarian differentiation by suppressing dmrt1 expression via nuclear estrogen receptors (nERs). Our results provide solid evidence for an interaction between cyp19a1a and dmrt1 in zebrafish gonadal differentiation, and for the dispensability of estrogens in controlling early folliculogenesis. [ABSTRACT FROM AUTHOR]

The role of mesoscale eddies in modulating the semidiurnal internal tide (SIT) in the northern South China Sea (SCS) is examined using the data from a cross-shaped mooring array. From November 2013 to January 2014, an anticyclonic eddy (AE) and cyclonic eddy (CE) pair crossed the westward SIT beam originating in Luzon Strait. Observations showed that, because of the current and stratification modulations by the eddy pair, the propagation speed of the mode-1 SIT sped up (slowed down) by up to 0.7ms-1 (0.4ms-1) within the AE's (CE's) southern portion. As a result of the spatially varying phase speed, the mode-1 SIT wave crest was clockwise rotated (counterclockwise rotated) within the AE(CE) core, while it exhibited convex and concave (concave and convex) patterns on the southern and northern peripheries of theAE(CE), respectively. In midto-late November, most of the mode-1 SIT energy was refracted by the AEaway from Dongsha Island toward the north part of the northern SCS, which resulted in enhanced internal solitary waves (ISWs) there. Corresponding to the energy refraction, responses of the depth-integrated mode-1 SIT energy to the eddies were generally in phase at the along-beam-direction moorings but out of phase in the south and north parts of the northern SCS at the cross-beam-direction moorings. From late December to early January, intensified mode-2 SIT was observed, whose energy was likely transferred from the mode-1 SIT through eddy-wave interactions. The observation results reported here are helpful to improve the capability to predict internal tides and ISWs in the northern SCS. [ABSTRACT FROM AUTHOR]

Background: Limited data are available regarding intermediate and long-term outcomes of transcatheter closure (TCC) of coronary cameral fistulas (CCFs) in the pediatric patients. Methods: All pediatric patients diagnosed with CCFs who were scheduled to undergo TCC between 2005 and 2019 were retrospectively enrolled in the study. Results: A total of 66 patients (median age: 3.93 years, median weight: 15 kg) underwent attempted TCC of CCFs. Immediate successful device implantation was achieved in 62 patients, and immediate complete occlusion was achieved in 44 patients (44/62%, 71.0%). The closure procedure was waived in 2 patients due to anatomical factors. A total of 6 periprocedural complications occurred in 5 patients, including acute myocardial infarction (n= 3), procedure-related death (n= 1), device embolization (n= 1), and rupture of tricuspid chordae tendineae (n= 1). The acute procedural success rate was 89.4% (59/66), while the acute complication rate was 9.1% (6/66). Follow-up data were collected for 58 (93.5%) out of 62 patients at a median of 9.3 years (range: 3.0-15.7 years). 10 adverse events occurred in 9 patients, including 5 follow-up complications (1 aortic valve perforation, 1 coronary thrombosis, 1 progressive aneurysmal dilation after reintervention, and 2 cases of new-onset tricuspid valve prolapse with significant regurgitation), and 5 closure failure with large residual shunts. The intermediate and long-term adverse event rate was 17.2% (10/58). The anatomical features associated with both acute and follow-up adverse events were large CCFs (p = 0.005), and giant coronary artery aneurysms (CAAs) (p = 0.029). Conclusions: TCC of CCFs in infants and children appears to be effective and is associated with a relatively low complication rate. Large CCFs and giant CAAs represent a higher risk of both acute and intermediate and long-term adverse events after closure. [ABSTRACT FROM AUTHOR]

In this study, the complete cDNA sequence (1552 bp) of the cold-inducible RNA binding protein gene (cirbp gene) was successfully cloned from the liver in Acanthopagrus schlegelii (initial weight: 15.0 ± 2.3 g). Results showed that Ascirbp (cirbp gene from A. schlegelii) gene has 24 phosphorylation sites, no signal peptide, and no transmembrane helix structure. AsCIRBP, with a molecular weight of 18.84 ku and an isoelectric point of 9.04 was a stable protein that encodes 182 amino acids. Subcellular localization analysis of this protein showed that it was located in the nucleus. Sequence alignment results showed that the AsCIRBP amino acid sequences of various fishes including black porgy were highly conserved, especially the RNA recognition motif (RRM). Those results of real-time quantitative PCR (qRT-PCR) demonstrated that Ascirbp gene was specifically expressed in the liver tissue of black porgy and its expression was significantly increased under cold stress or cold acclimation. The RNA interference experiment results showed that Ascirbp-dsRNA could suppress the expression of Ascirbp gene in the liver of black porgy through intraperitoneal injection. After silencing the expression of Ascirbp gene, RNAi groups were more severely damaged in the structure of the liver tissue and more prone to apoptosis under cold stress than control groups. The results of the study on the linkage between Ascirbp gene expression and mitochondrial apoptosis pathways showed that changes in the expression of the Ascirbp gene had a significant effect on the expression of key genes of apoptosis. The most striking result from silencing the expression of the Ascirbp gene was that expressions of the bcl-2 and apaf-1 gene in the liver of black porgy decreased significantly, which can block the normal apoptotic process. After the disruption of the normal apoptotic process, the expressions of p53, bax, cyto-c, caspase-9, caspase-3, diablo, and caspase-1 gene were significantly affected. These results suggest that Ascirbp gene can inhibit apoptosis and protect tissue structure in the liver tissue of black porgy at low temperatures. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the implementation of pharmacist-prescribed hormonal contraceptives in California after a recent expansion of pharmacists' scope of practice.Methods: A probability sample of 480 licensed California retail pharmacies (stratified by nonrural or rural location and independent or chain status) was included in a cross-sectional "secret shopper" telephone survey assessing the availability of pharmacist-prescribed hormonal contraceptives and service details. Survey data were analyzed using weighted descriptive statistics, CIs, and Wald tests.Results: Findings included data from 457 pharmacies (response rate 95.2%). Only 5.1% of pharmacies reported providing pharmacist-prescribed hormonal contraceptives (95% CI 2.9-7.2%). This proportion did not differ significantly between rural and nonrural pharmacies (P=.83) nor between independent and chain pharmacies (P=.40). Five of the 22 pharmacies that were providing pharmacist-prescribed hormonal contraceptives informed secret shoppers that all allowed hormonal methods were available; most of these pharmacies (77.3%) did proactively describe that a health history was required before receiving medications. Only half of pharmacies providing pharmacist-prescribed hormonal contraceptives would do so for minors although this was allowed by law.Conclusion: In the first year after statewide protocol implementation, only a small proportion of retail pharmacies across California has begun offering hormonal contraception services. In the absence of additional supportive legislation regarding reimbursement for pharmacist services, increases in scope of practice regulations to build a larger network of contraceptive providers may not be effective in increasing access to birth control. [ABSTRACT FROM AUTHOR]

This article proposes a method of locating and recognizing lockholes in shipping container corner castings. This method converts the original image of the containers captured by a camera into the HSV (Hue, Saturation, Value) color space. To reduce the influence of the surface color of the containers and lights from the environment on the locating and recognizing algorithm, most noisy points of the image are filtered by binarization and a morphology opening operation to make the features of the containers clearer in the image. Thus, the container body can be separated from the total image. Then, the position and size of the corner castings are defined through calculation based on the international standard of the shipping container size. Lastly, by using this method, we can locate the corner casting in the image by using the General Hough Transform fitting algorithm onto ellipses. [ABSTRACT FROM AUTHOR]

The welded hollow spherical joint is the most common form of the spatial grid structure, but the corrosion treatment at the joint is difficult. There are many corrosion problems of the welded hollow spherical joint in the actual structure, which brings hidden problems to structural safety. To study the effects of uniform corrosion on the key mechanical properties of welded hollow spherical joints, the joint refinement FEM in one typical size is built considering the effect of uniform corrosion through the method of the element birth and death, and the tensile, compressive, and bending performance of the FEM has been analyzed. Based on the analysis results, the relation curves between the three bearing capacities of the welded hollow spherical joint and the uniform corrosion degree are given. The results show that the influence of early corrosion on the joint tensile and compressive performance is not obvious. After corrosion to a certain extent, the loss of tensile and compressive capacity has a significant linear relationship with the degree of corrosion, and the loss of bending capacity has a significant quadratic curve relationship with the degree of corrosion from the initial stage. This study can provide a theoretical reference for a better understanding of the mechanical properties of welded hollow spherical joints in one typical size after corrosion to evaluate structural safety. [ABSTRACT FROM AUTHOR]

Ocean surface waves induced by wind forcing and topographic effects are a crucial physical process at the air-sea interface, which significantly affect typhoon development, ocean mixing, etc. Higher-resolution wave modeling can simulate more accurate wave states, but requires huge computational resources, making it difficult for Earth system models to include ocean waves as a fast-response physical process. Given that high-resolution Earth system models are in demand, efficient high-precision wave simulation is necessary and urgent. Based on the wave dispersion relation, we design a new wave modeling framework using a multiscale grid system. It has the fewest number of fine grids and reasonable grid spacing in deep water areas. We compare the performance of wave simulation using different spatial propagation schemes, reveal the different reasons for wave simulation differences in the westerly zone and the active tropical cyclone region, and quantify the matching of spatial resolutions between wave models and wind forcing. A series of numerical experiments show that this new modeling framework can more precisely simulate wave states in shallow water areas without losing accuracy in the deep ocean while costing a small fraction of traditional simulations with uniform fine-gridding space. With affordable computational expenses, the new ocean surface wave modeling can be implemented into high-resolution Earth system models, which may significantly improve the simulation of the atmospheric planetary boundary layer and upper-ocean mixing. [ABSTRACT FROM AUTHOR]

This article describes a systematic study of the roles played by hydroxide in controlling the deposition of Au on Ag nanocubes for the fabrication of diversified Ag-Au bimetallic nanocrystals. The synthesis simply involves the titration of aqueous HAuCl4 into an aqueous suspension of Ag nanocubes in the presence of ascorbic acid (H2Asc), NaOH, and poly(vinylpyrrolidone) at room temperature. The OH- ions from NaOH can affect the reduction kinetics of the Au(III) precursor in a number of ways and thereby the deposition pathways of the Au atoms. First of all, the OH- can accelerate the reduction kinetics by neutralizing H2Asc into ascorbate monoanion (HAsc-), the true player behind the reduction power of ascorbic acid. Second, the OH- can neutralize the added HAuCl4 and progressively transform AuCl4- into AuCl3(OH)-, AuCl2(OH)2-, AuCl(OH)3-, or Au(OH)4- through ligand exchange, generating Au(III) precursors with increasingly lower reduction potentials and thus lower probability for galvanic replacement reaction with Ag nanocubes than AuCl4-. Third, the OH- can react with the Ag+ ions released from the galvanic reaction to generate Ag2O patches at the corners of Ag nanocubes. Our results indicate that the deposition of Au on Ag nanocubes can follow two distinct pathways depending on the initial pH of the reaction solution. When the initial pH is controlled in the range of 10.3-11.9, the reduction of Au(III) is initiated by Ag nanocubes but dominated by HAsc- afterward, leading to the formation of Ag@Au core-frame and then core-shell nanocubes. In contrast, if the initial pH is controlled in the range of 3.2-4.8, both the galvanic replacement with Ag nanocubes and the chemical reduction by HAsc- contribute to the conversion of Au(III) to Au atoms. The Ag+ ions released from the galvanic replacement can also be reduced by HAsc- to transform Ag nanocubes into Ag@Ag-Au concave nanocubes with hollow interiors and alloyed walls. [ABSTRACT FROM AUTHOR]