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Clustering is an unsupervised learning process, hence it is difficult to find the optimal cluster number. Cluster validation is a process in which a cluster validity index (CVI) is constructed to evaluate the quality of clustering results and determine the optimal cluster number. Firstly, the mathematical description of clustering and the classification of CVIs are introduced. Then, 12 CVIs only considering the geometry information of the data set, 6 CVIs only considering the degree of membership, and 9 CVIs considering both the geometry information of the data set and the degree of membership are reviewed respectively based on different components in the indices. And the status quo of each type of CVIs is analyzed. Afterwards, the studies of other types of CVIs, such as external and stability-based indices, are briefly summarized. Finally, we point out the main challenges and research directions in the area of cluster validation. [ABSTRACT FROM AUTHOR]

• Enhanced myeloid differentiation tendency and myeloid-related gene signatures were observed in MRL/lpr lupus mice. • IBM-MSCT partially restored phenotypic and transcriptional alterations in lineage-biased HSPCs. • Genes related to myeloid differentiation and immune response were down-regulated after co-culture with UC-MSCs. • Beyond mediating inflammation, MSCT held the potential to maintain hematopoiesis. The hematopoietic homeostasis in the bone marrow is inextricably intertwined with the immune milieu in peripheral circulation. Researches investigating the pathogenesis of systemic lupus erythematosus (SLE) have defined considerable secretion of inflammatory mediators and activation of pro-inflammatory cells. However, the impacts of "extrinsic" factors on hematopoietic stem and progenitor cells (HSPCs) remain unclear, and it is uncertain whether treatments can help coordinate the biased differentiation. In this study, we showed differences in the proportions of common myeloid progenitors (CMP) and myeloid output in the bone marrow of premorbid and morbid MRL/lpr mice using flow cytometry. RNA-seq analysis of lineage-affiliated transcriptional factors and dysregulated genes within lin- HSPCs revealed inflammation potentiation during disease progression. Further, intra-bone marrow mesenchymal stem cells transplantation (IBM-MSCT) partially coordinated myeloid generation and counteracted lupus-associated inflammation gene alterations, compared to intravenous injection. Additionally, co-culturing with umbilical cord mesenchymal stem cells (UC-MSCs) intervened in myeloid lineage tendency, as detected by RT-qPCR of myeloid-related genes. Our research demonstrated enhanced tendency toward myeloid differentiation and highlighted the feasibility of IBM-MSCT for lineage-biased HSPCs in MRL/lpr lupus model, providing novel insight into hematopoiesis and MSC-related treatments for SLE. [ABSTRACT FROM AUTHOR]

[Display omitted] • The XLDR largely balanced most nutrient levels from upstream to downstream. • Reservoirs upstream nutrient levels induced nutrient disparities in the Yellow River in various periods. • The nutrient retention efficiency of the XLDR was assessed using a mass balance model. • Enhanced source effect of the XLDR for DIP lowered DIN/DIP and DSi/DIP downstream. Global dam construction and reservoir artificial regulations change the biogeochemical processes of nutrients along river networks. Herein, nutrients and hydrologic parameters were analyzed to ascertain their spatiotemporal heterogeneity in the Yellow River and assess the retention effect of nutrients in the Xiaolangdi Reservoir (XLDR). Nutrients increased upstream of reservoirs (the Sanmenxia Reservoir and XLDR) due to the inflow of tributaries (Wei River and Fen River). The XLDR maintained a balanced effect on most nutrient levels from upstream of reservoirs to downstream by the disparities in biogeochemical processes during various periods, including biotic assimilation consumption in the upper layer and regeneration and release in the lower layer during the Drainage period; limited water residence time of the XLDR and constrained biotic assimilation processes in the Flood control period; vertical water mixing in the Impoundment period. The disparities of most nutrient levels upstream of reservoirs played a crucial role in nutrient characteristics in the Yellow River during various periods. The higher DSi levels derived from enhanced physical erosion and chemical weathering of rock/soil responded to the higher water discharge and suspended particulate matter levels upstream and in the Yellow River during the Flood control and Impoundment periods; however, the lower DIN (dissolved inorganic nitrogen) and TDP (total dissolved phosphorus) resulted from the point pollution source and amplified water dilution effect. We demonstrated that the XLDR acted as a nutrient source for DIN, DIP and DSi based on the mass balance model in a hydrological year (June 2017-May 2018), with retention efficiency (RET f) of −1.4 %, −11% and −7%, respectively. The decreased RET f of DIP primarily stemmed from the pronounced reservoir source effect in the Drainage period. Consequently, the XLDR could relieve the P limitation downstream and estuary by changing the nutrient stoichiometry ratios of outflow. [ABSTRACT FROM AUTHOR]

Abstract: Three new zinc(II) complexes Zn(L1)2 (1), Zn2L2(OAc)3 (2) and Zn2L3(OAc)3 (3) have been synthesized by using Zn(OAc)2·2H2O and potentially multidentate Schiff base ligands HL1 (2-((1-hydroxybutan-2-ylimino)methyl)-6-methoxyphenol), HL2 (2-((1-hydroxy-2-methyl-propan-2-ylimino)methyl)-6-methoxyphenol) and HL3 (2-((2-hydroxypropylimino)-methyl)-6-methoxyphenol), respectively. These Schiff base ligands are the condensation product of o-vanillin and corresponding amino alcohols. All the three complexes 1, 2 and 3 have been characterized by elemental analysis, IR, single crystal X-ray diffraction and fluorescence studies. Structural studies reveal that 1 is a mononuclear complex whereas in dinuclear complexes 2 and 3 the two Zn(II) centers are held together by deprotonated Schiff base ligands and acetates. All the synthesized complexes display intraligand (π→π*) fluorescence and can potentially serve as photoactive materials. [Copyright &y& Elsevier]

A dense bridge-like tissue named the myodural bridge (MDB) connecting the suboccipital muscles to the spinal dura mater was originally discovered in humans. However, recent animal studies have revealed that the MDB appears to be an evolutionarily conserved anatomic structure which may have significant physiological functions. Our previous investigations have confirmed the existence of the MDB in finless porpoises. The present authors conducted research to expound on the specificity of the MDB in the porpoise Neophocana asiaeorientalis (N.asiaeorientalis). Five carcasses of N.asiaeorientalis, with formalin fixation, were used for the present study. Two of the carcasses were used for head and neck CT scanning, three-dimensional reconstructions, and gross dissection of the suboccipital region. Another carcass was used for a P45 plastination study. Also, a carcass was used for a histological analysis of the suboccipital region and also one was used for a Scanning Electron Microscopy study. The results revealed that the MDB of the N.asiaeorientalis is actually an independent muscle originating from the caudal border of the occiput, passing through the posterior atlanto-occipital interspace, and then attaches to the cervical spinal dura mater. Thus the so called MDB of the N.asiaeorientalis is actually an independent and uniquely specialized muscle. Based on the origin and insertion of this muscle, the present authors name it the 'Occipital-Dural Muscle'. It appears that the direct pull of this muscle on the cervical spinal dura mater may affect the circulation of the cerebrospinal fluid by altering the volume of the subarachnoid space via a pumping action. [ABSTRACT FROM AUTHOR]

Continental crust has long been considered too buoyant to be subducted beneath another continent, although geophysical evidence in collision zones predict continental crust subduction. This is particularly significant where upper continental crust is detached allowing the lower continental crust to subduct, albeit the mechanism of such subduction and recycling of the upper continental crust remain poorly understood. Here, we investigate Paleocene S-type magmatic and volcanic rocks from the Linzizong volcanic succession in the southern Lhasa block of Tibet. These rocks exhibit highly enriched 87Sr/86Sr, 207Pb/206Pb and 208Pb/206Pb together with depleted 143Nd/144Nd isotope ratios. The geochemical and isotopic features of these rocks are consistent with those of modern upper continental crust. We conclude that these Paleocene S-type volcanic and magmatic rocks originated from the melting of the upper continental crust from microcontinent subduction during the late stage of India–Asia convergence. [ABSTRACT FROM AUTHOR]

The article discusses a study that focuses on the geological characteristics of Rongna copper-gold-silver epithermal ore deposits located in Duolong copper ore concentration area in Northern Tibet, China. Topics discussed include classification of epithermal-porphyry copper mineralization system into high-sulfidation, medium sulfidation and low sulfidation types; composition of copper sulfides including digenite, enargite, bornite; and impact of deposits discovery on mineral prospecting.

Thermal insulating coatings effectively reduce heat loss, helping to save energy and reduce emissions. However, their thermal insulation performance decreases notably as temperature rises due to a single inhibition for heat transfer. Additionally, they have limited high-temperature resistance. To overcome these challenges. We developed a composite thermal insulation coating (CTIC). It was prepared through simple physical blending and can be effectively combined with various substrates. It achieves effective suppression of heat conduction and heat radiation, demonstrating excellent thermal insulation capabilities owing to the synergistic effect of fumed silica, Al 2 O 3 , and MnO 2. It exhibited a low thermal conductivity of 0.0843 W/(m·K) at 500 °C. The 10 mm CTIC decreased the high temperature from 1008.9 °C to 339.5 °C. Moreover, the CTIC could withstand temperatures of up to 1200 °C. This work offers fresh insights into the design of thermal insulating coatings. • Al 2 O 3 and MnO 2 can enhance radiation thermal insulation. • Fumed silica significantly inhibits both solid and gaseous thermal conduction • Simultaneously inhibiting heat conduction and heat radiation can significantly improve thermal insulation performance in high-temperature environments. [ABSTRACT FROM AUTHOR]

The Press-Pack Injection Enhanced Gate Transistor (PP-IEGT) technology is frequently employed in converters for high power systems. In the device packaging, the imbalanced current sharing among chips has become a significant issue for device reliability. Considering the semiconductor structure of IEGT is different from the conventional power devices, the main prerequisite for fully quantifying the current distribution is to establish a suitable electrical model for IEGT. Thus, this paper proposes an IEGT single chip lumped-charge model taking into account the effect of carrier injection enhancement in the emitter. Furthermore, as for the parallel branches in PP-IEGT, the parasitic inductance of the drive board and pillars within the package are extracted by Ansys simulation, and the validity of Ansys simulation is verified by the port S-parameter method. Finally, combining the electrical model and the effect of mutual inductance, the switching inconsistency is evaluated. It is demonstrated that the farther the branch from the gate inlet, the greater the gate inductance withstands. Besides, the mutual inductance is an important factor to influence the electrical parameter distribution. Both mutual coupling coefficient and current density display degressive trends with the increases of the gap between parallel chips. • Proposes an IEGT single chip lumped-charge model considering the effect of carrier injection enhancement in the emitter. • Extracted parasitic inductance of PP-IEGT driver boards and pillars. • Combining the lumped-charge model and the effect of mutual inductance, the switching inconsistency is evaluated. • Mutual inductance is an important factor to influence the electrical parameter distribution. [ABSTRACT FROM AUTHOR]

Object detection is an essential computer vision task that aims to detect target objects from an image. The traditional models are insufficient to generate a high-quality anchor box. To solve the problem, we propose a novel joint model called guided anchoring Region proposal networks and Cascading Grid Region Convolutional Neural Networks (RCGrid R-CNN), enhancing the ability of object detection. Our proposed model design is a joint object detection algorithm containing an anchor-based and an anchor-free branch in parallel and symmetry. In the anchor-based, we use nine-point spatial information fusion to obtain better anchor box location and introduce the shape prediction method of Guided Anchoring Region Proposal Networks (GA-RPN) to enhance the accuracy of the predicted anchor box. In the anchor-free branch, we introduce the Feature Selective Anchor-Free module (FSAF) to reduce the overlapping anchor boxes to obtain a more accurate anchor box. Furthermore, inspired by cascading theory, we cascade the new-designed detectors to improve the ability of object detection by setting a gradually increasing Intersection over Union (IoU) threshold. Compared with typical baseline models, we comprehensively evaluated our model by conducting experiments on two open datasets: Pascal VOC2007 and COCO2017. The experimental results demonstrate the effectiveness of RCGrid R-CNN in producing a high-quality anchor box. [ABSTRACT FROM AUTHOR]

Study Design: A scanning electron microscopic study performed on three cadaveric specimens focused on the human suboccipital region, specifically, myodural bridge (MDB).Objective: This study showed the connection form of the MDB among the suboccipital muscles, the posterior atlanto-occipital membrane (PAOM) and the spinal dura mater (SDM), and provided an ultrastructural morphological basis for the functional studies of the MDB.Summary Of Background Data: Since the myodural bridge was first discovered by Hack, researches on its morphology and functions had been progressing continuously. However, at present, research results about MDB were still limited to the gross anatomical and histological level. There was no research report showing the MDB's ultrastructural morphology and its ultrastructural connection forms between PAOM and SDM.Methods: A scanning electron microscope (SEM) was used to observe the connection of myodural bridge fibers with PAOM and SDM in atlanto-occipital and atlanto-axial interspaces, and the connection forms were analyzed.Results: Under the SEM, it was observed that there were clear direct connections between the suboccipital muscles and the PAOM and SDM in the atlanto-occipital and atlanto-axial spaces. These connections were myodural bridge. The fibers of the myodural bridge merged into the spinal dura mater and gradually became a superficial layer of the spinal dura mater.Conclusion: MDB fibers merged into the SDM and became part of the SDM in the atlanto-occipital and atlanto-axial space. MDB could transfer tension and pulling force to the SDM effectively, during the contraction or relaxation of the suboccipital muscles.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

A new initial orbit determination (IOD) method using single-site very short arc radar observations is proposed. The method uses slant range, azimuth, and elevation angles to determine the position vector and uses higher order radial measurements (velocity, acceleration, and jerk) to determine the velocity vector. The IOD accuracy based on the geometric dilution of precision (GDOP) metric is analyzed using a linearization approach. Relations between the GDOP and the observation geometry are investigated under a near-circular constraint and the optimal observation geometry for determining the velocity vector is identified. Monte Carlo simulations are presented for a typical low-Earth orbit satellite under two observation geometry configurations. The results demonstrate that the proposed method is feasible for very short arc initial orbit determination. [ABSTRACT FROM AUTHOR]

In this article, we propose an effective mixed extracting method for anisotropic constitutive parameters of periodically loaded substrate integrated waveguide (SIW). This method takes the advantage of both scattering parameters retrieval theory and the equivalent homogeneous medium dispersion analysis, which could accurately and effectively extract the equivalent constitutive parameters of the periodically loaded SIW. With this method, the corresponding constitutive parameters of the six typical patterns of periodically loaded SIW schemes are accurately extracted, verified, explained, and compared for their performance. It can be used to quantitatively predict the miniaturization potential of each unit cell and sequentially evaluate the performance as an integrated component. In addition, in terms of application, with the aid of equivalent parameters extracted by the proposed method, a slow-wave SIW evanescent mode filter centered at 12.64 GHz with a frequency bandwidth of 300 MHz is synthesized, fabricated, and measured. In the meanwhile, the theory of slow-wave evanescent mode filter is further consummated, by introducing the dual factors of enhanced permittivity and permeability, as well as analyzing respective advantages in filter synthesis. Measurements and simulation results show good agreement, which embodies the role of the method in guiding the design of actual microwave devices. [ABSTRACT FROM AUTHOR]

Due to the lack of uniform standards for pathological cell detection, it is difficult to identify. In order to improve the accuracy of pathological cell identification, this study combines the actual situation of cell detection based on traditional particle algorithm to construct a C-V model based on level set algorithm and curve evolution theory, which realizes the effective separation of different substances inside the cell. At the same time, in order to effectively extract the characteristics of cell images, this paper uses the global research method to extract the features of the research object and adopts the improved gray level co-occurrence matrix to extract the texture features, thus effectively improving the feature extraction quality. In addition, in order to study the accuracy of the algorithm model identification in this study, this paper designs a comparative experiment for performance analysis. The research shows that the proposed algorithm model has good performance, can achieve accurate recognition and feature extraction of pathological cells, has certain practical effects, and can provide theoretical reference for subsequent related research. [ABSTRACT FROM AUTHOR]

We aimed to investigate the factors associated with vitamin D deficiency and changes in 25 (OH)D levels, as well as the impact of those changes on disease activity and renal function among SLE patients. This retrospective cohort study was based on the medical records of SLE patients hospitalized between 2010 and 2021. We collected relevant information from this patient population. Logistic regression analysis was employed to determine the factors associated with vitamin D deficiency and increased 25 (OH)D levels, and we calculated the odds ratios (ORs) and 95% confidence intervals (CIs) accordingly. At baseline, among the 1257 SLE patients, the median and interquartile range of 25 (OH)D levels were 14 (9, 20) ng/ml, with 953 (75.8%) patients exhibiting 25 (OH)D deficiency (< 20 ng/ml). The presence of 25 (OH)D deficiency was found to be associated with renal involvement and a high glucocorticoid (GC) maintenance dose. Among the 383 patients who were followed up for an average of 18 months, an increase of at least 100% in 25 (OH)D levels was positively associated with a decreased GC maintenance dose and vitamin D3 supplementation, with adjusted odds ratios(OR) (95% confidence interval [CI]) of 2.16 (1.02, 4.59) and 1300 (70, 22300), respectively. Furthermore, an increased level of 25 (OH)D was significantly associated with a decrease in the Disease Activity Index 2000 score and the urinary protein/creatinine ratio. Patients with SLE have low vitamin D levels, especially those with impaired kidney function. Increased 25 (OH)D levels can be achieved through supplementation with high doses of vitamin D3 and are associated with improvements in disease activity and the urinary protein/creatinine ratio. [ABSTRACT FROM AUTHOR]

The gold abundance in basic rocks, which normally varies between 0.5 and 5 ppb, has served as a very important indicator in many geoscience studies, including those focused on the planetary differentiation, redistribution of elements during the crustal process, and ore genesis. However, because gold is a monoisotopic element that exhibits a nugget effect, it is very difficult to quantify its ultra-low levels in rocks, which significantly limits our understanding of the origin of gold and its circulation between the Earth crust, mantle, and core. In this work, we summarize various sample digestion and combined preconcentration methods for the determination of gold amounts in rocks. They include fire assay, fire assay combined with Te coprecipitation and instrumental neutron activation analysis (INAA) or laser ablation inductively coupled plasma mass spectrometry, fusion combined with Te coprecipitation and anion exchange resins, dry chlorination, wet acid digestion combined with precipitation, ion exchange resins, solvent extraction, polyurethane foam, extraction chromatography, novel solid adsorbents, and direct determination by INAA. In addition, the faced challenges and future perspectives in this field are discussed. [ABSTRACT FROM AUTHOR]

The Cross River, Calabar River, and Great Kwa River together form a network of an estuary system otherwise known as the Cross River Estuary system (CRES). Studies of dissolved nutrients and water mass dynamics were conducted mainly in February 2017. Nutrients measured included NO 3 −, NO 2 −, NH 4 +, dissolved inorganic phosphate (DIP), total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), dissolved organic nitrogen (DON), dissolved organic phosphorus (DOP) and dissolved silicate (DSi). The rivers were enriched with DSi and depleted of DIP. Dissolved nutrients were more elevated in the Great Kwa River than Cross River and Calabar River. The levels of DSi and DIN were less than average global concentrations, and that of river estuaries affected by anthropogenic activities. DON was the major form of TDN in the Calabar River estuary, and averagely accounted for 68–76% of TDN pool, while DOP accounted for ∼ 54–75% of TDP pool. Similarly, DON was the dominant form of TDN, and represented 75–84% of TDN pool in the Cross River estuary. In contrast, TDN was dominated by DIN, which accounted for 76–84% of TDN pool, while DIP accounted for 56–61% of TDP pool in the Great Kwa River estuary. There was a switch from DOP (67% of TDP) dominated river water to DIP (67% of TDP) dominated estuarine water in the Cross River estuary, due to enrichment of DIP in the lower Cross River estuary. The adjacent shelf was dominated by DON (58% of TDN) and DIP (70% of TDP). Based on nutrient molar ratios, primary production was strongly limited by DIP, especially in the riverine regions, and switched to DIN limitation in the adjacent shelf. Nutrients in the CRES behaved non-conservatively, and were affected by biogeochemical and physical processes. Nutrient budgets were estimated using the classical LOICZ steady−state box model. Atmospheric deposition of dissolved nutrients was very limited compared to riverine supply. The exchange time of water between the CRES and adjacent sea was ∼ 3.5 days, and may have affected biotic processes and nutrient transport. The CRES was an important source of DIP (137 × 103 moL day−1), DOP (92 × 103 moL day−1) and DON (4849 × 103 moL day−1) to the adjacent shelf, which was respectively 7, 4 and 2 times higher than the total riverine input. The ecosystem metabolism of the CRES, inferred from the ΔDIP system and ΔDIN system indicated that respiration of organic matter was higher than primary production with respiration rate of −15.7 × 106 mol C day−1 (−58 mmol C m−2 day−1), while nitrogen metabolism was −3.8 × 106 mol N day−1 (−14 mmol N m−2 d−1), suggesting that the CRES was heterotrophic, and denitrifying more than nitrogen fixation during this study. • Dissolved nutrient compositions and water mass dynamics were studied in the CRES and adjacent shelf during the dry season. • DSi and DIN were the most abundant nutrients in the rivers. • There was a shift from DIP limitation in the rivers to DIN limitation in the adjacent shelf. • The CRES is an important source of DIP, DOP and DON to the adjacent shelf. • The ecosystem metabolism indicated that the CRES is heterotrophic, and denitrifying more than nitrogen fixation. [ABSTRACT FROM AUTHOR]

In this article, the yolk–shell structure of resin‐based carbon spheres (YRFC) and the solid structure of resin‐based carbon spheres (SRFC) were prepared by condensation polymerization, and then novel spherical composites of poly(3,4‐propylenedioxythiophene)/YRFC (PProDOT/YRFC) and PProDOT/SRFC were obtained by in situ chemical oxidative polymerization. The prepared composites were characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible absorption spectra (UV–vis), Raman, X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), X‐ray photoelectron spectrometer (XPS), scanning electron microscope (SEM), and transmission electron microscopy (TEM). Electrochemical behavior of the composites were investigated with reference to their suitability as electrode materials in electrochemical capacitors (ECs), which were accomplished by a combination of cyclic voltammetry and galvanostatic charge/discharge cycles. The resultant PProDOT/YRFC composite showed ideal charge storage capacity with a specific capacitance of 327.5 F g−1 at the current density of 1 A g−1, which is much higher than that of the materials of PProDOT/SRFC (298.1 F g−1) and PProDOT (180.9 F g−1). Furthermore, long cycle life was achieved with the optimized PProDOT/YRFC and the capacitance retention is 87.3% after 10,000 charge/discharge processes, which was attributed to its uniformly dispersible fluffy structure. POLYM. COMPOS., 40:1989–1999, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

• The Sinongduo deposit is the first discovered low-sulfidation epithermal deposit. • The Pb-Zn mineralization is mainly concentrated in the range of 60.9–63.7 Ma. The Sinongduo Ag-Pb-Zn deposit is the first documented low-sulfidation epithermal deposit in Tibet and located on the southern side of the Longge'er-Gongbujiangda arc fault belt of the Lhasa terrane. The Ag-rich base metal veins and relatively low-grade breccias and stockworks in the Sinongduo deposit occur in the Paleocene high-potassium calc-alkaline to shoshonitic series volcanic rocks, including rhyolitic welded tuff breccia and volcanic breccia, rhyolitic ignimbrite, rhyolitic crystal fragment tufflava, rhyolite, and rhyolitic tuff. A nearly N-S-trending fault is the most important ore-controlling structure in the deposit. Galena and sphalerite are the dominant ore minerals in quartz-sericite-illite ± adularia veins, with subordinate argentite, pyrargyrite, native silver, chalcopyrite, pyrite and tennantite. The most widespread silver minerals are argentite, pyrargyrite, pearceite and native silver, which occur in fissures in Fe-Mn carbonates, jasper and early sulfides. The mineralization process can be divided into a pre-ore stage, main ore stage, and post-ore stage, and the main metallogenic stage is divided into the galena substage, sphalerite substage and silver minerals substage. Microthermometric analyses of the primary liquid-rich and vapour-rich fluid inclusions (FIs) in the sphalerite (SpII), main ore stage quartz (QzII) and post-ore stage quartz (QzIII) of the Sinongduo deposit indicate that the FIs in SpII, QzII and QzIII are mainly homogenized at temperatures of 197.2–280.8 °C, 185.6–290.4 °C and 148.2–218.7 °C with salinities of 1.40–5.71 wt% NaCl equiv., 1.59–5.71 wt% NaCl equiv. and 2.07–8.94 wt% NaCl equiv., respectively. These data indicate that the deposit was formed in a low-temperature and low-salinity environment, corroborating an epithermal system of mineralization. The O and H isotope compositions of the ore-forming fluids (δ18O = −0.6 to −6.3‰; δD = −177 to −151‰) indicate there was a major contribution from a meteoric water component to metallogenesis. All of the Pb isotope data from the metal sulfides and country rocks in the Sinongduo deposit in this study are similar and imply a close genetic relationship. The δ34S values of galena and sphalerite exhibit narrow distributions, ranging from +4.1‰ to +5.6‰ and from +7.6‰ to +8.4‰ respectively, with average values of +5.0‰ and +8.1‰, respectively, suggesting a uniform source. The Ar-Ar ages determined from sericite in the quartz-sericite-illite-sulfide veins range from 60.9 ± 0.7 to 63.1 ± 0.7 Ma, showing that the timing of epithermal Ag-Pb-Zn mineralization in the study area is consistent with the eruption of the Dianzhong Formation volcanic rocks (DVR) (U-Pb dating, 65–62 Ma), which indicates a genetic relationship. The characteristics of FIs, the H-O-S-Pb isotope data and the mineralization ages suggest that the ore-forming fluids were primarily sourced from circulating meteoric water, while S and Pb were derived from the DVR. Our results, combined with previous data on the regional geology, ore geology, FIs, and tectonic setting, indicate that the Sinongduo Ag-Pb-Zn deposit was produced in an epithermal system that formed on the southern side of the Longge'er-Gongbujiangda fault-block uplift belt, following the northward subduction of the Neo-Tethyan oceanic plate beneath the Asian continent. [ABSTRACT FROM AUTHOR]

In this paper, an electrochemical sensor was developed for detecting heavy metal ions by using contains O, S and N atoms polymer hollow nanosphere materials for the electrochemical simultaneous detection of Pb 2+ and Cu 2+ . poly(2,5-bis-(2,3-dihydrothieno[3,4-b][1,4]dioxyin-5-yl)pyridine) hollow nanosphere (poly(BPE)HNs) and poly(3,6-bis(3,4-ethylenedioxythienylpyridazine) hollow nanosphere (poly(EPE)HNs) were prepared by via chemical oxidative polymerization method. And the resulting products were characterized by FT-IR, UV–vis, TGA, XRD, TEM and SEM. The results indicated that two kinds of polymers were prepared successfully. Furthermore, the electrochemical sensors were applied for the electrochemical determination of Pb 2+ and Cu 2+ using DPV method. And the results indicated that poly(BPE)HNs modified glassy carbon electrode (poly(BPE)HNs/GCE) exhibited linear detection range from 0.012–4 μM and 0.016–4 μM for the Pb 2+ and Cu 2+ , with the sensitivity of 19.51 μA/μM and 4.87 μA/μM. The detection limits (S/N = 3) of 0.005 μM and 0.012 μM, respectively. The real sample analysis suggested that the poly(BPE)HNs modified electrode can be applied for the detection of the Pb 2+ and Cu 2+ ions in tap water samples. [ABSTRACT FROM AUTHOR]

• Alterations to the aquatic ecosystem of Dianchi Lake have led to an imbalance of nutrient retention. • Organic matter played an important role in the retention of nitrogen and phosphorus. • Anthropogenic factors exacerbated the nutrient retention imbalance in Dianchi Lake. • Comprehensive management is the key to mitigating the eutrophication of Dianchi Lake. Long-term anthropogenic nitrogen (N) and phosphorus (P) inputs have led to lake eutrophication and decreased environmental quality. However, the imbalance in nutrient cycling caused by ecosystem transformation during lake eutrophication is still unclear. The N, P, organic matter (OM) and their extractable forms in the sediment core of Dianchi Lake were investigated. Combining ecological data and geochronological techniques, a coupling relationship between the evolution of lake ecosystems and nutrient retention was established. The results show that the evolution of lake ecosystems promotes the accumulation and mobilization of N and P in sediments, leading to an imbalance in nutrient cycling in the lake system. From the "macrophyte-dominated" period to the "algae-dominated" period, the accumulation rates of potential mobile N and P (PMN, PMP) in sediments have significantly increased, and the retention efficiency of total N and P (TN, TP) has decreased. The increased TN/TP ratio (5.38 ± 1.52 ‒ 10.19 ± 2.94) and PMN/PMP ratio (4.34 ± 0.41 ‒ 8.85 ± 4.16), as well as the reduced humic-like/protein-like ratio (H/P, 11.18 ± 4.43 ‒ 5.97 ± 3.67), indicated an imbalance in nutrient retention during sedimentary diagenesis. Our results show that eutrophication has resulted in the potential mobilization of N in sediments exceeding P, providing new insights for further understanding the nutrient cycle in the lake system and strengthening lake management. [Display omitted] [ABSTRACT FROM AUTHOR]

Aquatic macrophytes and algae are the most important sources of autochthonous dissolved organic matter (DOM), and their transformation and reuse significantly affect aquatic ecosystem health. In this study, Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) was used to identify the molecular features between submerged macrophyte-derived DOM (SMDOM) and algae-derived DOM (ADOM). The photochemical heterogeneity between SMDOM and ADOM by UV 254 -irradiation and their molecular mechanism were also discussed. The results showed that the molecular abundance of SMDOM was dominated by lignin/CRAM-like structures, tannins, and concentrated aromatic structures (sum of 91.79%), while that of ADOM was dominated by lipids, proteins, and unsaturated hydrocarbons (sum of 60.30%). UV 254 -radiation resulted in a net reduction of tyrosine-like, tryptophan-like and terrestrial humic-like, and conversely a net production of marine humic-like. The light decay rate constants obtained by the multiple exponential function model fitting revealed that both tyrosine-like and tryptophan-like components of SMDOM could be rapidly and directly photodegraded, while the photodegradation of tryptophan-like in ADOM depended on the production of photosensitizers. The photo-refractory fractions of both SMDOM and ADOM were as follows: humic-like > tyrosine-like > tryptophan-like. Our results provide new insights into the fate of autochthonous DOM in aquatic ecosystems where "grass-algae" coexist or evolve. • Significant differences at the molecular level between SMDOM and ADOM. • SMDOM is more photolabile than ADOM. • The rapid photodegradation of SMDOM is attributed to abundant tannins. • Photodegradation of tryptophan-like in ADOM depends on photosensitizer production. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic relaxation and magnetization blocking barriers of tailor‐made homo‐ and heterodinuclear compounds [Dy2(opch)2(OAc)2(H2O)2]⋅MeOH (1) and [DyMn(opch)2(OAc)(MeOH)(H2O)2] (2), where H2opch is (E)‐N′‐(2‐hydroxy‐3‐methoxybenzylidene)pyrazine‐2‐carbohydrazide, were systematically investigated and the change in single‐molecule magnet behavior originating from targeted replacement of one dysprosium site in the Dy2 compound with manganese was elucidated through a combination of experimental and theoretical studies. A detailed comparative study on these closely related model compounds revealed remarkable changes of the crystal‐field splitting and anisotropy of the Dy site and the total exchange spectrum due to the replacement of Dy by Mn. The blocking barriers of these two compounds, which explain their different relaxation behaviors, were analyzed. The two Ising doublets arising from the magnetic interaction in the case of 1 are strongly uniaxial, with tunneling splittings smaller than 10−6 cm−1, and this leads to magnetic relaxation at temperatures exceeding the exchange energy (2.14 cm−1), which involves transition via the excited states corresponding to local transitions on the excited doublet at the Dy site. The third and fourth exchange doublets in 2 (located at 2.16 and 3.25 cm−1, respectively) show much larger tunneling splittings (of 10−4 and 10−3 cm−1, respectively), and thus open an important path for magnetic relaxation. [ABSTRACT FROM AUTHOR]

Dredged sediments derived from eutrophicated lakes poses hardness of sludge disposal and ecological risks. The proper pretreatment and utilization of dredged sediments presented a challenge. In this study, Dianchi Lake sediments were dredged, thermally treated and utilized as particle capping material in batch experiments. The effects of calcination on phosphorus speciation and sediment-water interface environment as well as P immobility mechanism were predominantly explored. The microstructures and chemical compositions of calcined sediments were investigated, indicating the porosity and mineralization components were greatly enhanced. The fractional analysis of phosphorus revealed that the calcination process reduced the percentage of unsteady phosphorus, transforming into stable inert phosphorus fractions (Al–P, Ca–P and Res-P), respectively, thereby minimized its mobility and eutrophication risk. Interestingly, calcination temperatures of 700 °C and 800 °C resulted in smaller releasing potentials and equilibrium phosphorus concentrations, despite having lower adsorption capacities than 550 °C. Furthermore, the results of redox potential monitoring showed that the thermally treated Dianchi Lake sediments could enhance the redox potential and dissolved oxygen in the surface sediment, indicating the amelioration of interfacial environment. The practical monitoring experiments confirmed the capping depressed the DTP to 0.031 mg L−1. The investigation of this study provided explicit evidence of Ca coupled P and aerobic Fe bound P strengthened the immobilization effects, and the development of sediment calcination demonstrates a promising strategy for alleviating the burden of endogenous pollution and improving aerobic environment, which are of great significance for lake ecological remediation. [Display omitted] • The composition and morphology of thermally treated sediments were characterized. • Phosphorus releasing potential was reduced at higher calcination temperatures. • The mobile phosphorus contents were dramatically decreased by thermal treatment. • SRP in overlying water can be effectively reduced by the increased Ca–P complexes. [ABSTRACT FROM AUTHOR]

The article discusses the research study conducted to examine the genesis and main differences of Jiama and Qulong Super-Large Deposit in Gangdese metallogenic belt in Tibet, China and providing a necessary reference for regional deposit prospecting. It mentions that rocks including skarn, porphyry, and hornfels serve as main ore hosts in the Jiama deposit. It further mentions the difference in the mineral resource composition and useful element series and have a regional denudation.

The article presents brief information on the geological characteristics of Xiachahe aluminum deposit at Zhenyuan, in Yunnan, China. Topics discussed include geological overview of mineral deposit in the north western region of the Ailaoshan golden belt in China, brief information on the characteristics of mineral orebody and ores, and impact of mineral alternation on the gathering and mineralization of the gold.

Black carbon (BC) and humic acid (HA) have been proposed to dominate the sorption behavior of phenanthrene in sediment. Nevertheless, little is known about the sorption mechanism that related to particle-scale by spiking of BC and HA in sediment particle size fractions. In this study, sorption isotherms for phenanthrene were determined in four particle-size sediment fractions (<2 μm, 2–31 μm, 31–63 μm and >63 μm) that amended with BC and HA, or not. The fitting results by Freundlich model indicated that the sediment particle size fractions amended with BC increased the sorption capacity and affinity for phenanthrene. Sediment coarser size fractions (31–63 μm and >63 μm) by spiking of BC contributed higher to sorption capacity factor (K F) and nonlinearity factor (n) than the finer size fractions (2–31 μm and <2 μm). By contrast, the sediment particle size fractions amended with HA enhanced the sorption distribution coefficient (K d), but reduced the sorption affinity for phenanthrene. All these phenomena are obviously affected by the distribution of heterogeneous organic matter that related to sediment particle-scale. Results of this work could help us better understand the impact of increased BC and HA content in sediments on the sorption of hydrophobic organic pollutants (HOCs) and predict the fate of HOCs in offshore sediments due to tidal action. [Display omitted] • Heterogeneous OM dominates the sorption of phenanthrene on sediments. • BC-amended increased the nonlinearity and affinity of phenanthrene sorption on sediments. • BC contributed higher K F of phenanthrene for coarse fractions than the fine fractions. • FA enhanced K d but reduced K F of phenanthrene for larger fractions rather than clay. [ABSTRACT FROM AUTHOR]

A class of slow-wave substrate integrated waveguide (SIW) structures patterned with microstrip polyline is presented, theoretically studied, and experimentally validated, which demonstrates some interesting slow-wave propagation effects. The slow-wave SIW (SW-SIW) enables the size reduction of a physically large circuit without sacrificing its performance. A size reduction of 40% of the lateral dimension is achieved with reference to that of the conventional SIW counterpart at the same cutoff frequency. Meanwhile, the phase velocity of the waveguide is also reduced by 40%, resulting in a smaller longitudinal dimension for a given electrical length. Both lateral and longitudinal effects give rise to a total size reduction, largely extending the operation range of SIW structures in the low-frequency region, which has often been restrained by a physical dimension-related cutoff frequency. Also, a transmission line-based two-dimensional (2-D) equivalent-circuit model is proposed and deployed for the modeling and analysis of the slow-wave mechanism. The results from the equivalent-circuit model agrees very well with that from the full-wave simulations. Furthermore, a broadband microstrip to SW-SIW taper with good return loss is designed for measurement verification. Using the proposed SW-SIW structure, the size of conventional SIW-based microwave circuits such as power splitters, couplers, and filters can be further reduced in addition to the existing size-reduction techniques. [ABSTRACT FROM AUTHOR]

The Jiama deposit, located in the eastern part of the well-known Gangdese Metallogenic Belt on the Tibetan Plateau, is the largest porphyry Cu–polymetallic system in the region, with the largest exploration budget, and is economically viable in the Gangdese Belt to undergo large-scale development. The deposit is well preserved and has experienced little erosion. The proven resources of the deposit are 7.4 Mt Cu, 0.6 Mt Mo, 1.8 Mt Pb + Zn, 6.65 Moz Au, and 360.32 Moz Ag. The results presented in this paper are based on geological and tectonic mapping, geological logging, and other exploration work performed by members of the Jiama Exploration Project Team over a period of 6 years. We propose that the Jiama porphyry Cu–polymetallic system is composed of skarn Cu–polymetallic, hornfels Cu–Mo, porphyry Mo ± Cu, and distal Au mineralization. The development of skarn Cu–polymetallic orebodies at the Jiama deposit was controlled mainly by the contact zone between porphyries and marbles, an interlayer detachment zone, and the front zone of a gliding nappe structure. The hornfels Cu–Mo and porphyry Mo ± Cu orebodies were controlled mainly by a fracture system related to intrusions, and the distal Au mineralization resulted from late-stage hydrothermal alteration. On the basis of field geological logging, optical microscopy, and chemical analysis, we verify that the alteration zones in the Jiama deposit include potassic, phyllic, propylitic, and argillic alteration, with a local lithocap, as well as endoskarn and exoskarn zones. The endoskarn occurs mainly as epidote alteration in quartz diorite porphyry and granite porphyry, and is cut by massive andradite veins. The exoskarn includes garnet–pyroxene and wollastonite skarn, in which the mineralogy and mineral chemical compositions display an outward zonation with respect to the source porphyry. From the proximal skarn to the intermediate skarn to the distal skarn, the garnet/pyroxene ratio varies from > 20:1 to ~ 10:1 to ~ 5:1, the garnet color varies from red-brown to brown-green to green-yellow, and the average composition of garnet varies from Ad 80.1 Gr 18.9 (Sp + Py) 1.0 to Ad 76.3 Gr 23 (Sp + Py) 0.7 to Ad 59.5 Gr 39.5 (Sp + Py) 1.0 , respectively. The pyroxene is not as variable in composition as the garnet, and is primarily light green to white diopside with a maximum hedenbergite content of ~ 20% and an average composition of Di 88.6 Hd 8.9 Jo 2.5 . From the proximal skarn to the intermediate skarn to the distal skarn, the mineralization changes from Cu–Mo to Cu ± Mo to Pb–Zn ± Cu ± Au ores, respectively. The wollastonite skarn displays no zonation and hosts mainly bornite mineralization. The Cu and Mo mineralization is closely related to the potassic and phyllic zones in the porphyry–hornfels. Zircons from four mineralized porphyries yield U–Pb ages of 15.96 ± 0.5 Ma, 15.72 ± 0.14 Ma, 15.59 ± 0.09 Ma, and 15.48 ± 0.08 Ma. The Re–Os ages of molybdenite from the skarn, hornfels, and porphyry are 15.37 ± 0.15 Ma, 14.67 ± 0.37 Ma, and 14.66 ± 0.27 Ma, respectively. The present results are consistent with the findings of previous research on fluid inclusions, isotopes, and other such aspects. On the basis of the combined evidence, we propose a porphyry Cu–polymetallic system model for the Jiama deposit and suggest a regional exploration strategy that can be applied to prospecting for porphyry-skarn mineralization in the Lhasa area. [ABSTRACT FROM AUTHOR]

• TP distribution is significantly positively correlated with water depth. • Fe and Al are vital trace elements controlling the P distribution. • The ecosystem changes P retention mechanism by varying Ca and macrophyte distributions. • Water level uplift triggered the ecosystem degradation resulting in P release. Shallow lakes are more susceptible to eutrophication than deep lakes. The geochemical and biogeochemical mechanisms controlling the vulnerability to eutrophication for deep lakes and shallow lakes remain unknown. Therefore, we investigated the combined Phosphorus (P) retention mechanism with P fractions, water depth, distribution of P-binding metal elements, and macrophytes coverage in a degrading ecosystem of Erhai Lake. We concluded that different mechanisms control the P retention in deep-water areas and shallow-water areas. In shallow areas covered by macrophytes, the biogeochemical process manipulates the P retention by changing the total organic carbon (TOC), calcium (Ca) distributions and turbulence. In deep areas without macrophyte coverage, the aluminum (Al) and iron (Fe) distributions control the P retention by a physicochemical process. Manganese (Mn) was found to be a potential proxy in tracking the kinetic release and readsorb of redox-sensitive P (BD-P) in deep areas. The historical record and core sample indicate that the hydrological engineering induced water depth variation is a vital factor changing the ecosystem of Erhai Lake by forming a large area of intermediate area where macrophytes could only survive at low water level. The uplift of water level in the 1990s gradually changed the ecosystem of Erhai Lake from macrophyte-dominated to algal-macrophyte concomitant that reduced the accumulation of stable P fractions and their binding metals. Macrophytes were capable to preserve P in biomass in the macrophyte-dominated ecosystem, which released 150% and 72% of more labile organic P (NaOH25-nrP) and BD-P in the sediment after the deterioration than before, respectively. Therefore, water depth is a prerequisite to restoring the P preservation capacity of sediment and the macrophyte ecosystem. Further hydraulic engineering projects should consider the effect of water-level-variation-induced ecosystem transition. [Display omitted] [ABSTRACT FROM AUTHOR]

Electric power industry is a typical industry with high energy consumption and high emissions in China. To relieve the increasing environmental pressures and promote the sustainable development of China’s economy and society, it is urgent to take actions to reduce energy consumption and pollution emissions of China’s electric power industry. In this paper, we first present an overview of the development status of China’s electric power industry, including the total power generating capacity and proportions of different power generation methods, the development of renewable energy power generation, as well as the average utilization hours of different power generation equipment. Then, the development of energy conservation and emissions reduction of China’s electric power industry is studied. The indicators of energy conservation include coal consumption for power supply, power consumption rate of power plants and comprehensive line loss rate; while the contents of emissions reduction include desulfurization, emissions control and the comprehensive utilization of solid waste. Finally, suggestions in five aspects to promote energy conservation and emissions reduction of China’s electric power industry are presented. The five suggestions are improving power generation technologies, expanding renewable energy power generation, optimizing power generation process, strengthening monitoring and regulation, and promoting power generation rights and emissions trading. [ABSTRACT FROM AUTHOR]

Although the evolutionary game theory provides a powerful framework to investigate various social dilemmas, the traveler’s dilemma game (TDG) is hardly concerned under this platform within the applied mathematical communities. We put forward an improved traveler’s dilemma game model on two coupled lattices to investigate the effect of coupling effect on the evolution of cooperation based on the traveler’s dilemma game, where the coupling effect between two lattices is added into the strategy imitation process. Large quantities of simulations indicate that the cooperation behavior can be greatly varied when compared to those obtained on the traditionally single lattices. When the model parameter R surpasses a specific threshold, the cooperation will be greatly enhanced, but the cooperation may be inhibited if R is smaller than this threshold. Meanwhile, we also explore the relationship between the critical value R c leading to the extinction of cooperation and the strategy range parameter radius in our model. Our results are surprisingly conducive to understanding the cooperation behavior of traveler’s dilemma game within many real-world systems, especially for coupled and interdependent networked systems. [ABSTRACT FROM AUTHOR]

Internal P loading (IPL) is a severe problem for the remediation of eutrophic lakes that the release of sedimentary P impedes the reduction of P in the lakes. To control the IPL, in-situ capping is a widely used remediation to improve the P burial efficiency. However, a lack of study has been done to investigate the long-term climate change effect on the P burial and release mechanisms. Thus, we thoroughly investigated the evolution of the P accumulation and release in the sediment of Dianchi Lake, a eutrophic plateau lake. The stability of sedimental P, which determines the internal P loading, is predominantly affected by climate change, anthropogenic activities, and the macrophyte-to algal-dominated ecosystem transition. The sediment core indicates more Ca accumulated in the 1930s caused by climate change and corresponding biological responses resulting in the transition of stable P fractions, which generates a vulnerable ecosystem from eutrophication. The self-clarification helps the lake accumulate anthropogenic P pollutants in the sediment as stable forms until the degradation of the ecosystem. It shows the NaOH extractable P (NaOH-rP) and HCl-extractable P (HCl–P) preservation capacity in an algal-dominated lake decreases from 780 to 700 mg cm−2•a−1 to 170 and 270 mg cm−2•a−1 respectively. The most stable P fraction (Res-P) is predominantly affected by climate change rather than human activities that a constant reduction from 730 mg cm−2•a−1 to 70 mg cm−2•a−1 after the climate change event that subdued the microbial activity producing Res-P in the 1930s. The spatial distributions of P fractions imply that the macrophyte-dominated area has more efficiency in preserving stable P in the sediment, thus the restoration of macrophyte as well as the benthonic microbe community should be considered in the remediation engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: It is well-known that individual diversity is a typical feature within the collective population. To model this kind of characteristics, we propose an evolutionary model of public goods game with two types of players (named as A and B), where players are located on the sites of a square lattice satisfying the periodic boundary conditions. The evolution of the strategy distribution is governed by iterated strategy adoption from a randomly selected neighbor with a probability, which not only depends on the payoff difference between players, but also on the type of the neighbor. For B-type agents, we pose a pre-factor ( ) to the strategy transfer probability, which implies the lower teaching activity or strategy convincing performance; but is always set to be 1 for A-type agents, hence it means that A-type players are influential ones who own a larger strategy spreading chance. Furthermore, we also consider the competition between two opposite effects when the number of nearest neighbors ( ) is increased from 4 to 24. Within a range of the portion of A-type influential players, the inhomogeneous teaching activity in strategy transfer yields a relevant increase (dependent on ) in the density of cooperators characterizing the promotion of cooperation. Current findings are of utmost importance for us to understand the evolution of cooperation under many real-world circumstances, such as the natural, biological, economic and even social systems. [Copyright &y& Elsevier]

Abstract: In the smart grid environment, the flexible and diverse distributed generation (DG) and microgrid (MG) are attracting considerable attention. There are many key management and optimization issues involved in smart grid. As an important part of smart grid optimizations, the optimal load distribution of MG contributes to the efficient operation of MG in the smart grid environment. However, traditional optimal load distribution models of large-scale power generation systems are not fully applicable to MG for their distinct characteristics. In this paper, we first introduce the MG in smart grid and analyze its characteristics. Then, we present a review of the optimal load distribution models of MG in the smart grid environment, and point out the deficiencies of the existing models. Finally, a comprehensive optimal load distribution model of MG both in objective functions and constraints is established and discussed. [Copyright &y& Elsevier]

Four new polynuclear clusters [NaMnIII3MnII(HL)3(μ4-O)(μ1,1-N3)3]ClO4·CH3CH2OH·(H2O)3 (1), [NaMnIII3MnII(HL)3(μ4-O)(μ1,1-N3)2(μ1,3-N3)]ClO4·CH3CH2OH·H2O (2), [NaMnIII3MnII(HL)3(μ4-O)(HCOO)3]ClO4·(H2O)4 (3) and [NaMnIII3MnII(HL)3(μ4-O)(PhCOO)(H2O)2](ClO4)2·H2O·PhCOO·PhCOOH·CH3OH (4) have been obtained via self-assembly between 3-((2-hydroxy-3-methoxybenzylidene)amino)propane-1,2-diol (H3L: condensed from o-vanillin and 3-amino-1,2-propanediol) and the auxiliary bridges (N3−, HCOO−, PhCOO−, H2O) with Mn(ClO4)2·6H2O in the air-exposed methanol solution. The structures of 1–4 all contain [NaMnIII3MnII] units and show a very similar trigonal propeller-like shape. The valences of the metal ions were determined by detection of the Jahn–Teller distortion visible for MnII,III, and confirmed by bond-valence sum (BVS) calculations. Three MnIII ions and one MnII ion take the shape of a super-tetrahedron with the MnII ion lying above the triangular [Mn3O] plane constructed from three MnIII ions linked by a central μ4-O atom. The NaI ion which lies below the [Mn3O] plane is linked with MnIII ions through the oxygen atoms from Schiff base ligands. The main structural difference in the four clusters is caused by the different bridging modes among MnIII ions. A structural comparison of 1–4 demonstrates that the auxiliary ligands play a key role in governing the coordination motifs. Moreover, the magnetic properties of these clusters exhibit dominating antiferromagnetic exchange interaction between spin carriers of MnII,III. [ABSTRACT FROM AUTHOR]

Three new phenolate oxygen bridged transition metal complexes [Zn3(HL1)3(μ3-CH3O)]·(ClO4)2(H2O)3 ( 1), [Ni2(HL1)2(μ1,1-N3)(o-vanillin)]·H2O ( 2), [Ni3(HL2)2(PhCOO)2(PhCOOH)2(EtOH)2] ( 3) have been synthesized by metal ions and potentially multidentate Schiff base ligands (H2L1 = 2-((1-hydroxy-2-methylpropan-2-ylimino) methyl)-6-methoxyphenol; H3L2 = ( E)-1-((2-hydroxy-3-methoxy-benzylidene)amino)ethane-1,2-diol). All the three complexes 1, 2, and 3 have been characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction studies. Crystal structures reveal that complex 1 is a trinuclear incomplete cubane-like zinc cluster whereas complex 2 is a dinuclear nickel complex bridged by azide, and compound 3 is a trinuclear nickel complex. The luminescent property for complex 1 and magnetic behaviors for complexes 2 and 3 have been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Two novel tetranuclear zinc(II) clusters with different topological structures have been synthesized by using Zn(ClO4)2·6H2O, sodium azide and potentially multidentate Schiff base ligands containing different substituent groups. The two complexes have been characterized by elemental analysis, IR, single crystal X-ray diffraction and fluorescence studies. Structural studies reveal that [Zn4(HL1)4(μ1,1-N3)2(N3)2] (1) is a linear tetranuclear cluster whereas [Zn4(HL2)4(μ1,1-N3)4] (2) is a square-planar tetranuclear cluster. Both two complexes display intraligand (π→π*) fluorescence. Due to the heavy atom effect which increases the probability for intersystem crossing to the triplet state, the fluorescence intensity of complex 2 is much lower than that of complex 1. [Copyright &y& Elsevier]

We studied the evolution of cooperation in the prisoner's dilemma game on a square lattice where the size of the interaction neighborhood is considered. Firstly, the effects of noise and the cost-to-benefit ratio on the maintenance of cooperation were investigated. The results indicate that the cooperation frequency depends on the noise and cost-to-benefit ratio: cooperation reaches a climax as noise increases, but it monotonously decreases and even vanishes with the ratio increasing. Furthermore, we investigated how the size of the interaction neighborhood affects the emergence of cooperation in detail. Our study demonstrates that cooperation is remarkably enhanced by an increase in the size of the interaction neighborhood. However, cooperation died out when the size of the interaction neighborhood became too large since the system was similar to the mean-field system. On this basis, a cluster-forming mechanism acting among cooperators was also explored, and it showed that the moderate range of the neighborhood size is beneficial for forming larger cooperative clusters. Finally, large-scale Monte Carlo simulations were carried out to visualize and interpret these phenomena explicitly. [ABSTRACT FROM AUTHOR]

With the aid of specific microstructures in a subwavelength array, time-reversed electromagnetic wave can display spatial super-resolution focusing in far-field zone. A subwavelength array of planar monopoles is proposed in this paper. Each element of the array, the planar monopole, is etched aperiodically with many microstructured complementary split rings. An important property of this antenna is that if multiple such planar monopoles are placed face to face, the proposed array can perform time-reversal far-field focusing with a spatial super-resolution as small as one twentieth of a wavelength. The validity of the proposed array with super-resolution characteristics is verified by the communication experiments with a data rate of 660 Mbit/s. The proposed subwavelength array is easy-to-design and convenient for integration. [ABSTRACT FROM AUTHOR]

On the basis of the technique of time reversal (TR), through adding dispersive delay lines to each element of a TR mirror, a method for low contrast tumour detection is proposed. When compared with a conventional detection method, the proposed method improves refocusing onto a low dielectric contrast tumour. The method does not require an accurate estimate of the position of the tumour. The theoretical basis for the approach is given and numerical simulated results demonstrate the capability of the proposed method. [ABSTRACT FROM AUTHOR]

The article discusses a study that focuses on the minerals, geological alteration and fluid basics of the first high sulfidation epithermal-porphyry copper-gold deposits in Tibet, China. Topics discussed include discovery of some new copper-sulfur and copper-iron-sulfur minerals; role of temperature and salinity in fluid inclusions and mixing of meteoricwater and porphyry fluid to form deposits in low temperature and salinity.

On the basis of the technique of time reversal (TR), a new method for low dielectric contrast target detection in clutter by adding dispersive delay lines (DDLs) to each element of the TR mirror (TRM) is proposed. When compared with a conventional TR system, the proposed method improves refocusing to a target by reducing the impact of other scatterers in the environment. The proposed method makes it unnecessary to estimate the position of the target and removes the need for subsequent subtraction as traditionally required. Theoretical and numerical simulated results demonstrate the proposed method. [ABSTRACT FROM AUTHOR]

Background: Cervical cancer is the second most common female cancer globally, and it is vital to detect cervical cancer with low cost at an early stage using automated screening methods of high accuracy, especially in areas with insufficient medical resources. Automatic detection of cervical intraepithelial neoplasia (CIN) can effectively prevent cervical cancer.Objectives: Due to the deficiency of standard and accessible colposcopy image datasets, we present a dataset containing 4753 colposcopy images acquired from 679 patients in three states (acetic acid reaction, green filter, and iodine test) for detection of cervical intraepithelial neoplasia. Based on this dataset, a new computer-aided method for cervical cancer screening was proposed.Methods: We employed a wide range of methods to comprehensively evaluate our proposed dataset. Hand-crafted feature extraction methods and deep learning methods were used for the performance verification of the multistate colposcopy image (MSCI) dataset. Importantly, we propose a gated recurrent convolutional neural network (C-GCNN) for colposcopy image analysis that considers time series and combined multistate cervical images for CIN grading.Results: The experimental results showed that the proposed C-GCNN model achieves the best classification performance in CIN grading compared with hand-crafted feature extraction methods and classic deep learning methods. The results showed an accuracy of 96.87 %, a sensitivity of 95.68 %, and a specificity of 98.72 %.Conclusion: A multistate colposcopy image dataset (MSCI) is proposed. A CIN grading model (C-GCNN) based on the MSCI dataset is established, which provides a potential method for automated cervical cancer screening. [ABSTRACT FROM AUTHOR]

Models for deep derivation of ophiolitic chromite from the mantle transition zone versus magmatic crystallization at lithospheric level are now highly controversial due to the discovery of ultrahigh-pressure (UHP) and super-reduced (SuR) minerals in ophiolitic chromitites and the presence of silicate mineral exsolution lamellae in chromite grains. According to experimental studies, chromite grains crystallized at low-pressures cannot exsolve silicate phases because of their low contents of CaO and SiO 2. However, clinopyroxene needles in chromite grains from the Stillwater Complex, which is a typical layered mafic-ultramafic intrusion crystallized at crustal level, show morphological, compositional and crystallographic features very similar to exsolution lamellae in ophiolitic chromite grains. We propose that the Stillwater clinopyroxene 'lamellae' represent minute melt inclusions that were attached parallel to branches of skeletal chromite where they were trapped during continued growth of the grain. This interpretation is supported by the orientations of the lamella-like clinopyroxene and the coexistence of larger clinopyroxene inclusions and apatite crystals along with the clinopyroxene needles. Another possibility is that these lamella-like minerals precipitated from melt/fluid that filled cracks in the chromite grains. Trails of tiny inclusions preserved in some healed fractures are consistent with this mechanism, but are inconsistent with the regular orientations of most of the needle-like 'inclusions'. The presence of such features in the Stillwater chromitites raises serious questions regarding the origin and significance of silicate lamellae in ophiolitic chromite grains and the use of such features to determine the depth of crystallization. • First report of lamella-like clinopyroxene in chromite of the Stillwater mafic-ultramafic complex. • The occurrence of amorphous grains having similar composition to clinopyroxene in chromite grains. • High-pressure conditions may not be required to form clinopyroxene 'lamella' in ophiolitic chromite and their host chromite. [ABSTRACT FROM AUTHOR]

• A magnetic cobalt-iron modified porous carbon was developed by microwave activation. • The developed magnetic sorbent exhibits excellent Hg0 removal performance. • Chemisorption oxygen and lattice oxygen participate in the removal of Hg0. • Hg0 adsorption capacity is 4833.3 μg/g, far exceeding common AC and magnetic sorbents. • Cobalt-iron mixed oxide modified porous carbon has a good regeneration performance. In this article, a magnetic cobalt-iron modified porous carbon derived from agricultural wastes by microwave and steam activation was developed to remove elemental mercury in coal-fired flue gas. The effects of operating parameters on Hg0 capture were discussed. Reaction mechanism and regeneration performance were also studied. Results show that the activation of microwave and steam significantly improves the pore structure of the porous carbon. The ultrasound-assisted impregnation promotes the dispersion of cobalt oxides and iron oxides on the samples. The Co 0.4 Fe 12 /RSWU(500) sorbent exhibits highest Hg0 removal efficiency at 130 °C. The characterization analysis shows that cobalt oxides and iron oxides are the main active components for Hg0 removal. The XPS analysis suggests that the chemisorption oxygen and the lattice oxygen (derived from Co3+/Co2+ and Fe3+/Fe2+) participate in the Hg0 capture process. Moreover, the cobalt-iron mixed oxide modified porous carbon has a good regeneration performance, which is conductive to reduce the costs in the future application. [ABSTRACT FROM AUTHOR]

In recent years, a new Internet-based unsecured credit model, peer-to-peer (P2P) lending, is flourishing and has become a successful complement to the traditional credit business. However, credit risk remains inevitable. A key challenge is creating a default prediction model that can effectively and accurately predict the default probability of each loan for a P2P lending platform. Due to the characteristics of P2P lending credit data, such as high dimension and class imbalance, conventional statistical models and machine learning algorithms cannot effectively and accurately predict default probability. To address this issue, a decision tree model-based heterogeneous ensemble default prediction model is proposed in this paper for accurate prediction of customer default in P2P lending. Gradient boosting decision trees (GBDT), extreme gradient boosting (XGBoost) and light gradient boosting machine (LightGBM) are employed as individual classifiers to create a heterogeneous ensemble learning-based default prediction model. Learning model-based feature ranking is applied to P2P lending credit data, and individual classifiers undergo hyperparameter optimization. Finally, comparison with benchmark models shows that the prediction model can achieve desirable prediction results and thus effectively solve the challenge of predictions based on high-dimensional and imbalanced data. • A novel decision tree model is proposed for the default prediction in P2P lending. • The model can deal with high dimension, sparsity and imbalanced data. • The model can make the prediction with high efficiency and accuracy. [ABSTRACT FROM AUTHOR]

Protozoan pathogens secrete nanosized particles called extracellular vesicles (EVs) to facilitate their survival and chronic infection. Here, we show the inhibition by Plasmodium berghei NK65 blood stage‐derived EVs of the proliferative response of CD4+ T cells in response to antigen presentation. Importantly, these results were confirmed in vivo by the capacity of EVs to diminish the ovalbumin‐specific delayed type hypersensitivity response. We identified two proteins associated with EVs, the histamine releasing factor (HRF) and the elongation factor 1α (EF‐1α) that were found to have immunosuppressive activities. Interestingly, in contrast to WT parasites, EVs from genetically HRF‐ and EF‐1α‐deficient parasites failed to inhibit T cell responses in vitro and in vivo. At the level of T cells, we demonstrated that EVs from WT parasites dephosphorylate key molecules (PLCγ1, Akt, and ERK) of the T cell receptor signalling cascade. Remarkably, immunisation with EF‐1α alone or in combination with HRF conferred a long‐lasting antiparasite protection and immune memory. In conclusion, we identified a new mechanism by which P. berghei‐derived EVs exert their immunosuppressive functions by altering T cell responses. The identification of two highly conserved immune suppressive factors offers new conceptual strategies to overcome EV‐mediated immune suppression in malaria‐infected individuals. [ABSTRACT FROM AUTHOR]

Background: Percutaneous vertebroplasy (PVP) might lead to significant radiation exposure to patients, operators, and operating room personnel. Therefore, radiaton exposure is a concern. The aim of this study was to present a remote control cement delivery device and study whether it can reduce dose exposue to operators.Methods: After meticulous preoperative preparation, a series of 40 osteoporosis patients were treated with unilateral approach PVP using the new cement delivery divice. We compared levels of fluoroscopic exposure to operator standing on different places during operation. group A: operator stood about 4 meters away from X-ray tube behind the lead sheet. group B: operator stood adjacent to patient as using conventional manual cement delivery device.Results: During whole operation process, radiation dose to the operator (group A) was 0.10 ± 0.03 (0.07-0.15) μSv, group B was 12.09 ± 4.67 (10-20) μSv. a difference that was found to be statistically significant (P < 0.001) between group A and group B.Conclusion: New cement delivery device plus meticulous preoperative preparation can significantly decrease radiation dose to operators. [ABSTRACT FROM AUTHOR]