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ObjectiveAfter fully lifting coronavirus disease 2019 (COVID-19) pandemic control measures in mainland China in 12/2022, the incidence of COVID-19 has increased markedly, making it difficult to meet the general time-in-range (TIR) requirement. We investigated a more clinically practical TIR threshold and examined its association with the prognosis of COVID-19 patients with type 2 diabetes(T2D).Research design and methods63 T2D patients complicated with COVID-19 were evaluated. Patients were divided into favorable outcome group and adverse outcome group according to whether achieving composite endpoint (a >20-day length of stay, intensive care unit admission, mechanical ventilation use, or death). TIR, the time-below-range (TBR) and the time-above-range (TAR) were calculated from intermittently scanned continuous glucose monitoring. Logistic regression analysis and other statistical methods were used to analyze the correlation between glucose variability and prognosis to establish the appropriate reference range of TIR.ResultsTIR with thresholds of 80 to 190 mg/dL was significantly associated with favorable outcomes. An increase of 1% in TIR is connected with a reduction of 3.70% in the risk of adverse outcomes. The Youden index was highest when the TIR was 54.73%, and the sensitivity and specificity were 58.30% and 77.80%, respectively. After accounting for confounding variables, our analysis revealed that threshold target ranges (TARs) ranging from 200 mg/dL to 230 mg/dL significantly augmented the likelihood of adverse outcomes.ConclusionThe TIR threshold of 80 to 190 mg/dL has a comparatively high predictive value of the prognosis of COVID-19. TIR >54.73% was associated with a decreased risk of adverse outcomes. These findings provide clinically critical insights into possible avenues to improve outcomes for COVID-19 patients with T2D.

Both genetic and environmental factors affect the morphology of oysters. Molecular identification is currently the primary means of species identification, but it is inconvenient and costly. In this research, we evaluated the effectiveness of geometric morphometric (GM) techniques in distinguishing between two oyster species, Crassostrea gigas and C. ariakensis. We used traditional morphometric and GM methods, including principal component analysis (PCA), thin-plate spline analysis (TPS) and canonical variable analysis (CVA), to identify specific features that distinguish the two species. We found that differences in shape can be visualised using GM methods. The Procrustes analysis revealed significant differences in shell morphology between C. gigas and C. ariakensis. The shells of C. ariakensis are more prominent at the widest point and are more scattered and have a greater variety of shapes. The shells of C. gigas are more oval in shape. PCA results indicated that PC1 explained 45.22%, PC2 explained 22.09% and PC3 explained 10.98% of the variation between the two species, which suggests that the main morphological differences are concentrated in these three principal components. Combining the TPS analysis function plots showed that the shell shape of C. ariakensis is mainly elongated and spindle-shaped, whereas the shell shape of C. gigas is more oval. The CVA results showed that the classification rate for the two species reached 100% which means that C. ariakensis and C. gigas have distinct differences in shell morphology and can be completely separated, based on morphological characteristics. Through these methods, a more comprehensive understanding of the morphological characteristics of different oyster populations can be obtained, providing a reference for oyster classification and identification.

The influence of different environmental factors on the infectivity of H1N1 influenza virus was measured. We found less than 1-log reduction when viruses were exposed to NaCl solutions up to 5 M or solutions with pH = 4 through 11 for one hour. The infectivity of the virus was sensitive to the solution temperature. A log reduction ranging from 2 to more than 6 was observed starting at 50 °C and spanning just 3 or 5 for 10- or 30 min exposures, respectively. Drying the virus in media on aluminum or polymer coupons for 48 h resulted in a log reduction of 4 when kept at room temperature, but less than one when kept at 4 °C or -20 °C. Log reduction greater than 6 occurred at room temperature after 3 days, but only 1-log reduction occurred at 4 and -20 °C after 6 days. Drying on different coinage achieved similar results, except for pennies, where more than 6-log reduction was observed after 24 h. HOCl was used to fog the aluminum and polymer surfaces, placed vertically, for 5 and 7.5 min to achieve a log reduction of 4 and for 6.5 respectively. Storage of opened solution containers for 9 months at ambient resulted in a decrease in chlorine concentration from 550 ppm to 240 ppm. Fogging with the old solution was still able to achieve a log reduction of 6.5 after 7.5 min fogging. The study indicates that exposure to common environmental conditions such as a wide pH range, high salinity, and low temperatures has only a minor effect on infectivity. which can persist for more than 5 days when dried on commonly encountered surfaces, allowing accumulation of infectious viral titre. Fogging with HOCl is an effective method of delivering disinfectants to large areas, achieving complete reduction of the viral titer on both horizontal and vertical surfaces.

Panax notoginseng saponins (PNSs) are used as industrial raw materials to produce many drugs to treat cardio-cerebrovascular diseases. However, it is a heat-sensitive plant, and its large-scale artificial cultivation is impeded by high temperature stress, leading to decreases in productivity and PNSs yield. Here, we examined exogenous foliar leucine to alleviate heat stress and explored the underlying mechanism using metabolomics. The results indicated that 3 and 5 mM exogenous foliar leucine significantly alleviated heat stress in one-year- and two-year-old P. notoginseng in pots and field trials. Exogenous foliar leucine enhanced the antioxidant capacity by increasing the activities of antioxidant enzymes (POD, SOD) and the contents of antioxidant metabolites (amino acids). Moreover, exogenous foliar leucine enhanced carbohydrate metabolism, including sugars (sucrose, maltose) and TCA cycle metabolites (citric acid, aconitic acid, succinic acid and fumaric acid), in P. notoginseng leaves, stems, and fibrous roots to improve the energy supply of plants and further alleviate heat stress. Field experiments further verified that exogenous foliar leucine increased the productivity and PNSs accumulation in P. notoginseng. These results suggest that leucine application is beneficial for improving the growth and quality of P. notoginseng under heat stress. It is therefore possible to develop plant growth regulators based on leucine to improve the heat resistance of P. notoginseng and other crops.

Green agriculture can minimize the negative impact of agriculture on the environment. As countries around the world strongly advocate green production and green life style, not only is consumers' awareness about green consumption rising, but the demand for green agricultural products at home and abroad is gradually increasing as well. Brand image has been a crucial factor for consumers to make their final purchasing decisions, thus playing a critical role in influencing the purchasing decisions of consumers. Based on the theory of the brand image, this paper undergoes a comprehensive theoretical and positive analysis and explores the influence mechanism of brand image of green agricultural products on consumers' purchasing intention. A hypothetical model with perceived value as mediators is constructed by us to examine the influence of brand image of green agricultural products on consumers' purchasing intention. A quantitative study was conducted for a random sample of 341 consumers who purchased green agricultural products in China according to a questionnaire-based survey using a cluster random sampling technique. The study showed that the overall image of agribusiness, the image of agricultural products, the social image of agribusiness, and the image of consumers are all positively related to consumption intention. The overall image of agribusiness, the image of agricultural products, the social image of agribusiness, and the image of consumers have a positive influence on perceived value. Moreover, perceived value plays a part in the mediating role in the influence of the overall image of agribusiness, the image of agricultural products, the social image of agribusiness, and the image of consumers on consumption intention. These findings shed lights on enterprises in establishing a scientific and effective brand strategy and building an excellent brand image. The research conclusion can provide new insight into how to enhance the consumption willingness for green agricultural products and promote sustainable development.

The Bay of Bengal (BoB) is conventionally believed to be a low productive, oligotrophic marine ecosystem, where the diazotroph communities presumed to play a vital role in adding “new” nitrogen through the nitrogen fixation process. However, the diazotroph communities in the oceanic region of the BoB are still poorly understood though it represents most of the seawater volume. The present study investigated a detailed account of the bacterioplankton community structure and distribution in the oceanic BoB during the winter monsoon using high throughput sequencing targeting the 16S rRNA and nifH genes. Our study observed diverse groups of bacterioplankton communities in the BoB including both cyanobacterial and non-cyanobacterial phylotypes. Cyanobacteria (Prochlorococcus spp. and Synechococcus spp.) and Proteobacteria (mainly α-, γ-, and δ-Proteobacteria) were the most abundant groups within the bacterial communities, possessing differential vertical distribution patterns. Cyanobacteria were more abundant in the surface waters, whereas Proteobacteria dominated the deeper layers (75 m). However, within the diazotroph communities, Proteobacteria (mainly γ-Proteobacteria) were the most dominant groups than Cyanobacteria. Function prediction based on PICRUSt revealed that nitrogen fixation might more active to add fixed nitrogen in the surface waters, while nitrogen removal pathways (denitrification and anammox) might stronger in deeper layers. Canonical correspondence analysis (CCA) indicated that temperature, salinity, and silicate were major environmental factors driving the distribution of bacterial communities. Additionally, phosphate was also an important factor in regulating the diazotroph communities in the surface water. Overall, this study provided detailed information on bacterial communities and their vital role in the nitrogen cycles in oligotrophic ecosystems.

Marine picocyanobacteria Synechococcus exhibit highly diverse pigment types (PTs) and hence possess great advantage to utilize different spectrum of light effectively and to occupy a wide range of light niches. In this study, we explored the diversity of Synechococcus PTs in the eastern Indian Ocean (EIO), surface water of Strait of Malacca (SSM), and coastal waters of Sri Lanka (SSL). All the detected PTs were phycourobilin (PUB) containing PT 3 and showed distinct distribution patterns. Low PUB PT 3a and partial chromatic acclimater PT 3eA dominated in coastal and shallow waters (SSM and SSL). In contrast, high PUB and chromatic acclimaters PT 3dA and PT 3c/3dB were mainly distributed in open ocean (EIO). PT 3dA and PT 3c/3dB occurred at similar depths of the lower euphotic layers but showed distinct distribution pattern that are partially exclusive, indicating that they compete with each other for the same light niche. Interestingly, the newly described PT 3f was detected with high relative abundances at all stations and particularly dominated in the upper euphotic layer in EIO, which was confirmed with PT-specific quantitative polymerase chain reaction (qPCR). The relative abundance of PT 3f was negatively correlated with nutrient level, implying that PT 3f is adapted to oligotrophic waters. Pronounced niche partition of different PTs was observed in the upper and lower layers of euphotic zone in EIO and SSM/SSL. Light, nutrients, and strong stratification may play important roles in the niche partition of different PTs. Further analysis about ecologically significant taxonomic units revealed high diversity within each PT at different locations, which provided insights for understanding specific PT with wide range of niches.

Na+ is the most abundant ion in living organisms and plays essential roles in regulating nutrient uptake, muscle contraction, and neurotransmission. The identification of Na+ in protein structures is crucial for gaining a deeper understanding of protein function in a physiological context. LeuT, a bacterial homolog of the neurotransmitter:sodium symporter family, uses the Na+ gradient to power the uptake of amino acids into cells and has been used as a paradigm for the study of Na+-dependent transport systems. We have devised a low-energy multi-crystal approach for characterizing low-Z (Z ≤ 20) anomalous scattering ions such as Na+, Mg2+, K+, and Ca2+ by combining Bijvoet-difference Fourier syntheses for ion detection and f” refinements for ion speciation. Using the approach, we experimentally identify two Na+ bound near the central leucine binding site in LeuT. Using LeuT microcrystals, we also demonstrate that Na+ may be depleted to study conformational changes in the LeuT transport cycle.

To examine the spatial pattern and controlling factors of the primary productivity (PP) of phytoplankton in the eastern Indian Ocean (EIO), deck-incubation carbon fixation (a 14C tracer technique) and the related hydrographic properties were measured at 15 locations during the pre-summer monsoon season (February–April 2017). There are knowledge gaps in the field observations of PP in the EIO. The estimated daily carbon production rates integrated over the photic zone ranged from 113 to 817 mgC m–2 d–1, with a mean of 522 mgC m–2 d–1. The mixed-layer integrated primary production (MLD-PP) ranged from 29.0 to 303.7 mgC m–2 d–1 (mean: 177.2 mgC m–2 d–1). The contribution of MLD-PP to the photic zone-integrated PP (PZI-PP) varied between 19 and 51% (mean: 36%). Strong spatial variability in the carbon fixation rates was found in the study region. Specifically, the surface primary production rates were relatively higher in the Bay of Bengal domain affected by riverine flux and lower in the equatorial domain owing to the presence of intermonsoonal Wyrtki jets, which were characterized by a depression of thermocline and nitracline. The PZI-PP exhibited a linear (positive) relationship with nutrient values, but with no significance, indicating a partial control of macronutrients and a light limitation of carbon fixation. As evident from the vertical profiles, the primary production process mainly occurred above the nitracline depth and at high photosynthetic efficiency. Phytoplankton (>5 μm), including dinoflagellates, Trichodesmium, coccolithophores, and dissolved nutrients, are thought to have been correlated with primary production during the study period. The measured on-deck biological data of our study allow for a general understanding of the trends in PP in the survey area of the EIO and can be incorporated into global primary production models.

ABSTRACT Management of crop root rot disease is one of the key factors in ensuring sustainable development in agricultural production. The accumulation of autotoxins and pathogens in soil has been reported as a primary driver of root rot diseases; however, less is known about the correlation of plants, their associated pathogens and microbiome mediated by autotoxins as well as the contributions autotoxins make to the occurrence of root rot disease. Here, we integrated metabolomic, transcriptomic, and rhizosphere microbiome analyses to identify the root cell wall degradants cellobiose and d-galacturonic acid as being induced by the autotoxic ginsenoside Rg1 of Panax notoginseng, and we found that exogenous cellobiose and d-galacturonic acid in addition to Rg1 could aggravate root rot disease by modifying the rhizosphere microbiome. Microorganisms that correlated positively with root rot disease were enriched and those that correlated negatively were suppressed by exogenous cellobiose, d-galacturonic acid, and Rg1. In particular, they promoted the growth and infection of the soilborne pathogen Ilyonectria destructans by upregulating pathogenicity-related genes. Cellobiose showed the highest ability to modify the microbiome and enhance pathogenicity, followed by Rg1 and then d-galacturonic acid. Collectively, autotoxins damaged root systems to release a series of cell wall degradants, some of which modified the rhizosphere microbiome so that the host plant became more susceptible to root rot disease. IMPORTANCE The accumulation of autotoxins and pathogens in soil has been reported as a primary driver of root rot disease and one of the key factors limiting sustainable development in agricultural production. However, less is known about the correlation of plants, their associated pathogens, and the microbiome mediated by autotoxins, as well as the contributions autotoxins make to the occurrence of root rot disease. In our study, we found that autotoxins can damage root systems, thus releasing a series of cell wall degradants, and both autotoxins and the cell wall degradants they induce could aggravate root rot disease by reassembling the rhizosphere microbiome, resulting in the enrichment of pathogens and microorganisms positively related to the disease but the suppression of beneficial microorganisms. Deciphering this mechanism among plants, their associated pathogens, and the microbiome mediated by autotoxins will advance our fundamental knowledge of and ability to degrade autotoxins or employ microbiome to alleviate root rot disease in agricultural systems.

The root of Panax notoginseng (Burk.), in which saponins are the major active components, is a famous traditional Chinese medicine used to stop bleeding and to decrease inflammation and heart disease. Inflorescence removal increases the yield and quality of P. notoginseng, but the underlying molecular mechanisms are unknown. Here, the differences between inflorescence-removal treatment and control groups of P. notoginseng were compared using transcriptomics and metabolomics analyses. Illumina sequencing of cDNA libraries prepared from the rhizomes, leaves and roots of the two groups independently identified 6,464, 4,584, and 7,220 differentially expressed genes (DEG), respectively. In total, 345 differentially expressed transcription factors (TFs), including MYB and WRKY family members, were induced by the inflorescence-removal treatment. Additionally, 215 DEGs involved in saponin terpenoid backbone biosynthetic pathways were identified. Most genes involved in the mevalonic acid (MVA) and methylerythritol phosphate (MEP) pathways were activated by inflorescence removal. The co-expression analysis showed that the low expression levels of flavonoid biosynthesis-related genes (e.g., C4H and F3H) decreased the biosynthesis and accumulation of some flavonoids after inflorescence removal. The results not only provide new insights into the fundamental mechanisms underlying the poorly studied inflorescence-removal process in P. notoginseng and other rhizome crops, but they also represent an important resource for future research on gene functions during inflorescence-removal treatments and the reproductive stage.

Microbial communities are composed of many rare species and a few abundant species. Considering the disproportionate importance of rare species for ecosystem functioning, it is important to understand the mechanisms structuring the rare and abundant components of a diverse community in response to environmental changes. Here, we used a 16S ribosomal RNA gene sequencing approach to investigate the bacterial community diversity in the Eastern Indian Ocean (EIO) during the monsoon and intermonsoon. We employed a phylogenetic null model and network analysis to evaluate the assembly processes and co-occurrence pattern of the microbial community. We found that higher bacterial diversity was detected in the intermonsoon with high temperature and low Chlorophyll a concentrations and N/P ratios. The balance between ecological deterministic processes and stochastic processes varied with seasons in the EIO. Meanwhile, conditionally rare taxa (CRT) were more likely modulated by variable selection processes than always rare taxa (ART) and abundant taxa (AT) (CRT > ART > AT). By linking assembly process and species co-occurrence, we demonstrated that the microbial co-occurrence associations tended to be higher when deterministic processes (mainly variable selection) were weaker. This negative trend was observed in rare species rather than abundant species. The linkage could enhance our understanding of the underlying mechanisms underpinning the generation and maintenance of microbial community diversity.

Abstract Background Tetraploid Thinopyrum elongatum (2n = 4x = 28) is a promising source of useful genes, including those related to adaptability and resistance to diverse biotic (Fusarium head blight, rust, powdery mildew, and yellow dwarf virus) and abiotic (cold, drought, and salt) stresses. However, gene transfer rates are low for this species and relatively few species-specific molecular markers are available. Results The wheat-tetraploid Th. elongatum line K17–841-1 derived from a cross between a hexaploid Trititrigia and Sichuan wheat cultivars was characterized based on sequential genomic and fluorescence in situ hybridizations and simple sequence repeat markers. We revealed that K17–841-1 is a 1E (1D) chromosomal substitution line that is highly resistant to stripe rust pathogen strains prevalent in China. By comparing the sequences generated during genotyping-by-sequencing (GBS), we obtained 597 specific fragments on the 1E chromosome of tetraploid Th. elongatum. A total of 235 primers were designed and 165 new Th. elongatum-specific markers were developed, with an efficiency of up to 70%. Marker validation analyses indicated that 25 specific markers can discriminate between the tetraploid Th. elongatum chromosomes and the chromosomes of other wheat-related species. An evaluation of the utility of these markers in a F2 breeding population suggested these markers are linked to the stripe rust resistance gene on chromosome 1E. Furthermore, 28 markers are unique to diploid Th. elongatum, tetraploid Th. elongatum, or decaploid Thinopyrum ponticum, which carry the E genome. Finally, 48 and 74 markers revealed polymorphisms between Thinopyrum E-genome- containing species and Thinopyrum bessarabicum (Eb) and Pseudoroegneria libanotica (St), respectively. Conclusions This new substitution line provide appropriate bridge–breeding–materials for alien gene introgression to improve wheat stripe rust resistance. The markers developed using GBS technology in this study may be useful for the high-throughput and accurate detection of tetraploid Th. elongatum DNA in diverse materials. They may also be relevant for investigating the genetic differences and phylogenetic relationships among E, Eb, St, and other closely-related genomes and for further characterizing these complex species.

Community detection in the network has become an invaluable tool to explore and reveal the internal organization of nodes. In particular, the target community detection focuses on discovering the “local” links within and connecting to the target community related to user's preference, which refers to a limited number of nodes in the whole network. A few works in the literature discuss the target community detection. In this paper, we propose a target community detection with user's preference and attribute subspace. Our method utilizes not only network structure but also node attributes within a certain subspace to quantify both internal consistency and external separability, which is able to capture a user preferred target community. First, the similarity between nodes is calculated via both attributes and structures, and the center node set of the target community can be obtained by extending the sample node given by the user with its neighbors. Second, an attribute subspace calculation method with entropy weights is established based on the center node set, and the attribute subspace of the target community can thus be deduced. Finally, the target community quality, which is the combination of internal connectivity and external separability, is defined, based on which the target community with a user's preference can be detected. The experimental results on both synthetic network and real-world network datasets demonstrated the efficiency and effectiveness of the proposed algorithm.

Adjusting planting density is a common agricultural practice used to achieve maximum yields. However, whether the quality of medicinal herbs can be improved by implementing appropriate planting densities is still uncertain. The medicinal crop Panax notoginseng was used to analyze the effects of planting density on growth and ginsenoside accumulation, and the possible mechanisms of these effects were revealed through metabonomics. The results showed that P. notoginseng achieved high ginsenoside accumulation at high planting densities (8 × 8 and 10 × 10 cm), while simultaneously achieved high biomass and ginsenoside accumulation at moderate planting density of 15 × 15 cm. At the moderate planting density, the primary metabolism (starch and sucrose metabolism) and secondary metabolism (the biosynthesis of phytohormone IAA and ginsenoside) of the plants were significantly enhanced. However, the strong intraspecific competition at the high planting densities resulted in stress as well as the accumulation of phytohormones (SA and JA), antioxidants (gentiobiose, oxalic acid, dehydroascorbic acid) and other stress resistance-related metabolites. Interestingly, the dry biomass and ginsenoside content were significantly lower at low densities (20 × 20 and 30 × 30 cm) with low intraspecific competition, which disturbed normal carbohydrate metabolism by upregulating galactose metabolism. In summary, an appropriate planting density was benefit for the growth and accumulation of ginsenosides in P. notoginseng by balancing primary metabolism and secondary metabolism.

Obtaining information on the genetic diversity and population structure of germplasm facilitates its use in wheat breeding programs. Recently, with the development of next-generation sequencing technology, genotyping-by-sequencing (GBS) has been used as a high-throughput and cost-effective molecular tool for examination of the genetic diversity of wheat breeding lines. In this study, GBS was used to characterize a population of 180 accessions of common wheat originating from Asia and Europe between the latitudes 30° and 45°N. In total, 24,767 high-quality single-nucleotide polymorphism (SNP) markers were used for analysis of genetic diversity and population structure. The B genome contained the highest number of SNPs, followed by the A and D genomes. The polymorphism information content was in the range of 0.1 to 0.4, with a mean of 0.26. The distribution of SNPs markers on the 21 chromosomes ranged from 243 on chromosome 4D to 2,337 on chromosome 3B. Structure and cluster analyses divided the panel of accessions into two subgroups (G1 and G2). G1 principally consisted of European and partial Asian accessions, and G2 comprised mainly accessions from the Middle East and partial Asia. Molecular analysis of variance showed that the genetic variation was greater within groups (99%) than between groups (1%). Comparison of the two subgroups indicated that G1 and G2 contained a high level of genetic diversity. The genetic diversity of G2 was slightly higher as indicated by the observed heterozygosity (Ho) = 0.23, and unbiased diversity index (uh) = 0.34. The present results will not only help breeders to understand the genetic diversity of wheat germplasm on the Eurasian continent between the latitudes of 30° and 45°N, but also provide valuable information for wheat genetic improvement through introgression of novel genetic variation in this region.

Shifts in phytoplankton phenology were observed in the Strait of Malacca (SM) and Sunda Shelf (SS), which were speculated to be potentially related to global warming and climate anomaly events. Such interactions between phytoplankton structure and physico-chemical factors were less known in narrow straits. Therefore, the spatial distribution pattern and diversity of surface phytoplankton assemblage, local hydrology, and nutrient regimes were investigated over the SM and SS (South China Sea, SCS) during 2017 and 2018 pre-monsoon season (spring). Diatoms, dinoflagellates, and cyanobacteria were representatives of microphytoplankton in the survey area. Total phytoplankton abundance peaked near Singapore Strait (SGS) and diminished toward SS. From the lower ratio of diatoms to dinoflagellates (

When maintaining and expanding national interests,our country’s information network has always been faced with the problem of “covering beyond its control,incompatible with information,slow in response to services and having security risks”.Building a space-ground integration information network is an effective way to deal with the challenges.Based on this,the status quo and trend of the development of the integrated world-wide information network system at home and abroad were analyzed.The concept,key technologies and implementation strategies of a global integration of information network architecture were given.

The approach of fast repetition rate fluorometry (FRRF) requires a conversion factor (Φe : C/nPSII) to derive ecologically-relevant carbon uptake rates (PPz,t). However, the required Φe : C/nPSII is commonly measured by 14C assimilation and varies greatly across phytoplankton taxonomy and environmental conditions. Consequently, the use of FRRF to estimate gross primary productivity (GPz,t), alone or in combination with other approaches, has been restricted by both inherent conversion and procedural inconsistencies. Within this study, based on a hypothesis that the non-photochemical quenching (NPQNSV) can be used as a proxy for the variability and magnitude of Φe : C/nPSII, we thus proposed an independent field model coupling with the NPQNSV-based Φe : C/nPSII for FRRF-derived carbon, without the need for additional Φe : C/nPSII in the Bay of Bengal (BOB). Therewith, this robust algorithm was verified by the parallel measures of electron transport rates and 14C-uptake PPz,t. NPQNSV is theoretically caused by the effects of excess irradiance pressure, however, it showed a light and depth-independent response on large spatial scales of the BOB. Trends observed for the maximum quantum efficiency (Fv/Fm), the quantum efficiency of energy conversion (Fq′/Fm′) and the efficiency of charge separation (Fq′/Fv′) were similar and representative, which displayed a relative maximum at the subsurface and were collectively limited by excess irradiance. In particular, most observed values of Fv/Fm in the BOB were only about half of the values expected for nutrient replete phytoplankton. FRRF-based estimates of electron transport at PSII (ETRRCII) varied significantly, from 0.01 to 8.01 mol e− mol RCII−1 s−1, and showed profound responses to depth and irradiance across the BOB, but fitting with the logistic model. N, P, and irradiance are key environmental drivers in explaining the broad-scale variability of photosynthetic parameters. Furthermore, taxonomic shifts and physiological changes may be better predictors of photosynthetic parameters, and facilitate the selection of better adapted species to optimize photosynthetic efficiency under any particular set of ambient light condition.

Microscopic flow in fractured porous media is a typical problem for the exploitation of tight reservoirs. The rapid-flow in the fractured porous-media is of great significance to efficient and continuous oil/gas exploitation. The fractures are expected to enhance flow conductivity and mass transfer between matrix and fractures, and to improve oil displacement during water flooding. However, the fractures may also lead to water channeling under some conditions. The understanding on the mechanism of the microscopic flow in the fractured porous media has been insufficient until now. In this paper, a two-dimensional pore-fracture network model is presented to study the role of fractures in the flow. The effects of two main dimensionless parameters, fracture length to network length lf/l and fracture density Nf/N, on the absolute permeability and the oil displacement efficiency are investigated. The results show that the flow in the matrix plays a controlling role at a low fracture density. Once the fracture density exceeds a certain value, the flow is controlled by fractures. With the increase of the fracture density, the oil displacement efficiency develops into three typical stages: when Nf/N < 0.1, the oil displacement efficiency increases rapidly; when 0.1 < Nf/N < 0.5, the oil displacement efficiency changes slowly; and when Nf/N > 0.5, the oil displacement efficiency decreases rapidly. In the case lf/l > 0.8, the water mainly flows through a concentrated path connected by some fractures, resulting in it bypassing most oil regions, and thus the oil displacement efficiency decreases rapidly, similar to the water channeling.

Longitudinal data on patient-reported outcomes (PROs), such as quality of life of patients, are frequently collected in clinical trials and other medical studies. Joint analysis of these data with survival times may improve the accuracy of statistical inferences, especially when PRO measurements may be missing after the death of patients. Classical linear mixed models are often used as the models for the longitudinal measurements in a joint analysis, but it may not be suitable for longitudinal PRO measurements with potential ceiling and floor effects caused by a large portion of patients who report either a maximum or minimum score. In this paper, we introduce a new joint model that uses a longitudinal Tobit model for the longitudinal outcomes with potential ceiling and floor effects and a Cox proportional hazard model for survival time with a random effect connecting these two models. An estimation procedure based on the partial likelihood and Laplace approximation is developed to estimate the parameters in both models, and a random weighting method is proposed to calculate the variances of these parameter estimators. Performances of the proposed procedures are evaluated through simulation studies and an application to the analysis of quality of life data from a clinical trial. [ABSTRACT FROM AUTHOR]

Extracellular forces transmitted through the cytoskeleton can deformthe cell nucleus. Large nuclear deformations increase the risk of disrupting the integrity of the nuclear envelope and causing DNA damage. The mechanical stability of the nucleus defines its capability to maintain nuclear shape by minimizing nuclear deformation and allowing strain to be minimized when deformed. Understanding the deformation and recovery behavior of the nucleus requires characterization of nuclear viscoelastic properties. Here, we quantified the decoupled viscoelastic parameters of the cell membrane, cytoskeleton, and the nucleus. The results indicate that the cytoskeleton enhances nuclear mechanical stability by lowering the effective deformability of the nucleus while maintaining nuclear sensitivity to mechanical stimuli. Additionally, the cytoskeleton decreases the strain energy release rate of the nucleus and might thus prevent shape change-induced structural damage to chromatin. [ABSTRACT FROM AUTHOR]

The characteristics of urban dust aerosols and the contributions of their natural and anthropogenic sources are of scientific interest as well as being of substantial sociopolitical and economic concern. Here we present the results of a comprehensive study of dust flux and magnetic signatures, including magnetic susceptibility (Χ) and the morphology and elemental composition of magnetic particulates, of atmospheric dustfall originating from natural dust sources in East Asia and local anthropogenic sources in Xi'an, China. The results reveal a significant inverse relationship, on a seasonal basis, between variations in dust flux and Χ. By comparing Χ records of desert surface sediments and local polluted dust, the relative contributions of natural and anthropogenic sources can be estimated for the urban atmospheric dustfall. Analysis using Scanning Electron Microscopy (SEM) combined with Energy Dispersive Spectroscopy (EDS) indicates that magnetic particulates from different sources have distinctive morphological and elemental characteristics. Detrital magnetic particles originating from natural sources are characterized by relatively smooth surfaces with Fe and O as the major elements and a minor contribution from Ti. The anthropogenic particles have angular, spherule, aggregate, and porous shapes with distinctive contributions from marker elements, including S, Cr, Cu, Zn, Ni, Mn and Ca. Our results demonstrate that this multidisciplinary approach is effective in distinguishing dust derived from distant natural sources and local anthropogenic sources, and for quantitative assessment of the contributions of the two end-members. [ABSTRACT FROM AUTHOR]

Extracellular forces transmitted through the cytoskeleton can deform the cell nucleus. Large nuclear deformation increases the risk of disrupting the nuclear envelope's integrity and causing DNA damage. Mechanical stability of the nucleus defines its capability of maintaining nuclear shape by minimizing nuclear deformation and recovering strain when deformed. Understanding the deformation and recovery behavior of the nucleus requires characterization of nuclear viscoelastic properties. Here, we quantified the decoupled viscoelastic parameters of the cell membrane, cytoskeleton, and the nucleus. The results indicate that the cytoskeleton enhances nuclear mechanical stability by lowering the effective deformability of the nucleus while maintaining nuclear sensitivity to mechanical stimuli. Additionally, the cytoskeleton decreases the strain energy release rate of the nucleus and might thus prevent shape change-induced structural damage to chromatin. [ABSTRACT FROM AUTHOR]

This study discussed and assessed the 12 biological quality elements (heavy metals and persistent organic pollutants, POPs) in marine commercial organism residues and its adjacent area of ecological environment in the Bohai Bay (BB) undertaken in 2007 and 2009 spring and autumn. Benthos was prominently dominated by the mollusc, and followed by crustacean, polychaetes, and echinoderm. Dominant phytoplankton was Skeletonema, Ditylum brightwelli, Nitzschia longissima, Thalassiosira ex-centiica, Thalassiosira rotula, etc. The abundant chain-formed Skeletonema is typically considered as a biological indicator of water quality, particularly, in relation to coastal environmental pollutions. 5 and 12 commercial species were detected in 2007 spring and autumn survey respectively and assessed by single factor pollution index method. The investigation of pollutant residual levels within these commercial organisms in BB indicated that heavy metals such as Cd, Cu, Zn, Pb, and Cr were extremely over-standard (type I standard). This investigation and assessment have vital importance for recognizing marine environment status and commercial organism health in the coastal region. [ABSTRACT FROM AUTHOR]

A comprehensive survey was conducted in the coastal area of Bohai Bay (117°50'E~118°'E and 39°4'N~12'N) during May 7 to 11, 2009. Environmental factors were surveyed in a grid of 20 stations during a rising tide and a falling tide. Phytoplankton samples were collected from 16 stations and microscopically examined in the lab. A total of 33 species which belongs to 3 phyla were detected in the study area, including Bacillariophyta (31 species, accounting for 93.94%), Cryptophyta (1 species, accounting for 3.03%) and Chlorophyta (1 species, accounting for 3.03%). The main phytoplankton groups were eurythermal and neritic autochthonous species, the dominant species were Skeletonema sp., Ditylum brightwellii, Nitzschia longissima, Coscinodiscus excentricus, Thalassiosira rotula, Rhizosolenia styliformis and Coscinodiscus jonesianus in this season. Cell abundance ranged from 2.429×104 cells/L to 4.51×105 cells/L with an average of 1.386×105 cells/L. Dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) ratios were 39.4:1 in rising tide and 41.64:1 in falling tide. Combined with history literatures, the nutrient limiting factor for phytoplankton growth could shift to phosphorus limitation from nitrogen limitation due to anthropogenic emissions in the last decade. Correlation analysis proved that SRP and pH were the main factors that control the phytoplankton growth in rising tide, while these factors had no obvious effect in falling tide. The periodic change of the phytoplankton community structure was not only influenced by physical process, but also influenced by the sea surface temperature (SST), nutrient concentration and other environmental factors. [ABSTRACT FROM AUTHOR]

Based on the survey records on netz-phytoplankton (>76 µm) collected in the South China Sea (SCS) during the cruise from the 21st August to the 18th October, 2012, the species composition, biodiversity and its spatial distribution were studied. The identified 326 phytoplankton species belonged to 75 genera and 4 phyla. Thalassionema nitzschioides was the most dominant species accounting for 33.24% of the total cell abundance, followed by Bacteriastrum furcatum - 8.69%. Whereas the phytoplankton cell abundance (cells l-1) was the highest in the Zhubi Reef (1106.45 ± 2475.38), the southern SCS (396.84 ± 969.87), the western SCS (90.82 ± 144.66) and the northern SCS (66.48 ± 70.89) in order. The distribution of phytoplankton appears to be affected by the Mekong river discharge and particles derived in Sumatra and Kalimantan from biomass burning, nutrient concentrations, the South China Sea Warm Current (SCSWC). The evaluation of biodiversity indices indicated the high level of species richness, evenness and biodiversity in the survey area. [ABSTRACT FROM AUTHOR]

Protoporphyrin IX (PPIX) produced following the administration of exogenous 5d-aminolevulinic acid is clinically approved for photodynamic therapy and fluorescence-guided resection in various jurisdictions around the world. For both applications, quantification of PPIX forms the basis for accurate therapeutic dose calculation and identification of malignant tissues for resection. While it is well established that the PPIX synthesis and accumulation rates are subject to the cell's biochemical microenvironment, the effect of the physical microenvironment, such as matrix stiffness, has received little attention to date. Here we studied the proliferation rate and PPIX synthesis and accumulation in two glioma cell lines U373 and U118 cultured under five different substrate conditions, including the conventional tissue culture plastic and polyacrylamide gels that simulated tissue stiffness of normal brain (1 kPa) and glioblastoma tumors (12 kPa). We found that the proliferation rate increased with substrate stiffness for both cell lines, but not in a linear fashion. PPIX concentration was significantly higher in cells cultured on tissue-simulating gels than on the much stiffer tissue culture plastic for both cell lines. These findings, albeit preliminary, suggest that the physical microenvironment might be an important determinant of tumor aggressiveness and PPIX synthesis in glioma cells. [ABSTRACT FROM AUTHOR]

The elasticity of the extracellular matrix profoundly affects biological responses of cells, but also their mechanical properties. Single cell mechanical properties are often measured by atomic force microscopy (AFM), but technical guidelines for AFM measurement of cells grown on soft substrates are not well established. In this study, the local and global elastic moduli of aortic valve interstitial cells (VICs) cultured on soft polyacrylamide substrates (3-144 kPa) were characterized via AFM force mapping using pyramidal and spherical tips, respectively. Local and global VIC modulus values both increased with substrate stiffness (p < 0.05), with the average local cell modulus being consistently two to three times greater than the global modulus (p < 0.05). For local measurements, a minimum of four measurements was required to observe the trend of increasing cell modulus with substrate stiffness, but there was no advantage to testing additional spots. The Hertz model was relatively accurate in estimating the global cell elastic modulus ( < 12% error, based on validated finite element analyses), despite the cells being of finite thickness and grown on deformable substrates, neither of which are accounted for in the Hertz model. The results of this study provide practical guidelines for efficient AFM-based measurement of the mechanical properties of cells on gels. They also provide new physiologically-relevant data on VIC mechanical properties and their correlation with substrate stiffness-dependent cytoskeletal changes, with relevance to heart valve mechanobiology and disease. [ABSTRACT FROM AUTHOR]