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Watersheds are the fundamental Earth surface functioning units that connect the land to aquatic systems. Many watershed-scale models represent hydrological processes but not biogeochemical reactive transport processes. This has limited our capability to understand and predict solute export, water chemistry and quality, and Earth system response to changing climate and anthropogenic conditions. Here we present a recently developed BioRT-Flux-PIHM (BioRT hereafter) v1.0, a watershed-scale biogeochemical reactive transport model. The model augments the previously developed RT-Flux-PIHM that integrates land-surface interactions, surface hydrology, and abiotic geochemical reactions. It enables the simulation of (1) shallow and deep-water partitioning to represent surface runoff, shallow soil water, and deeper groundwater and of (2) biotic processes including plant uptake, soil respiration, and nutrient transformation. The reactive transport part of the code has been verified against the widely used reactive transport code CrunchTope. BioRT-Flux-PIHM v1.0 has recently been applied in multiple watersheds under diverse climate, vegetation, and geological conditions. This paper briefly introduces the governing equations and model structure with a focus on new aspects of the model. It also showcases one hydrology example that simulates shallow and deep-water interactions and two biogeochemical examples relevant to nitrate and dissolved organic carbon (DOC). These examples are illustrated in two simulation modes of complexity. One is the spatially lumped mode (i.e., two land cells connected by one river segment) that focuses on processes and average behavior of a watershed. Another is the spatially distributed mode (i.e., hundreds of cells) that includes details of topography, land cover, and soil properties. Whereas the spatially lumped mode represents averaged properties and processes and temporal variations, the spatially distributed mode can be used to understand the impacts of spatial structure and identify hot spots of biogeochemical reactions. The model can be used to mechanistically understand coupled hydrological and biogeochemical processes under gradients of climate, vegetation, geology, and land use conditions.

Climate models predict amplified warming at high elevations in low latitudes, making tropical glacierized regions some of the most vulnerable hydrological systems in the world. Observations reveal decreasing streamflow due to retreating glaciers in the Andes, which hold 99 % of all tropical glaciers. However, the timescales over which meltwater contributes to streamflow and the pathways it takes – surface and subsurface – remain uncertain, hindering our ability to predict how shrinking glaciers will impact water resources. Two major contributors to this uncertainty are the sparsity of hydrologic measurements in tropical glacierized watersheds and the complication of hydrograph separation where there is year-round glacier melt. We address these challenges using a multi-method approach that employs repeat hydrochemical mixing model analysis, hydroclimatic time series analysis, and integrated watershed modeling. Each of these approaches interrogates distinct timescale relationships among meltwater, groundwater, and stream discharge. Our results challenge the commonly held conceptual model that glaciers buffer discharge variability. Instead, in a subhumid watershed on Volcán Chimborazo, Ecuador, glacier melt drives nearly all the variability in discharge (Pearson correlation coefficient of 0.89 in simulations), with glaciers contributing a broad range of 20 %–60 % or wider of discharge, mostly (86 %) through surface runoff on hourly timescales, but also through infiltration that increases annual groundwater contributions by nearly 20 %. We further found that rainfall may enhance glacier melt contributions to discharge at timescales that complement glacier melt production, possibly explaining why minimum discharge occurred at the study site during warm but dry El Niño conditions, which typically heighten melt in the Andes. Our findings caution against extrapolations from isolated measurements: stream discharge and glacier melt contributions in tropical glacierized systems can change substantially at hourly to interannual timescales, due to climatic variability and surface to subsurface flow processes.

Growing demand for an efficient land use above and below the ground is motivating cadastre and land management systems to move from traditional 2D systems toward three dimensional ones. Airborne laser technology offers direct acquisition of dense and accurate 3D data. In order to get 3D road this paper proposes a hierarchical algorithm to extract terrain point from LIDAR data. We stratify the raw LiDAR data according to the height, judge terrain points and non-terrain points by the connectivity. In the case of road network, it indicates the morphological characteristics of network structure with a certain length continuous strip and small difference in intensity. All these information, including elevation information, the intensity information, the morphological characteristics and other local features, are used for extracting the road network from DTM. Local morphological filtering method is implementing for finding clear boundaries and rich details of the road profile. Following the presentation of the algorithm results for this approach are shown and evaluated

The presence of multiple phases/ components within a nanocomposite material impacts the properties of a nanomaterial. Therefore, there is a need to estimate the phase fraction of each component present in a sample. Spurr-Myers proposed a valuable formula for estimating the rutile and anatase phase fraction of a TiO2 sample from X-ray diffraction. However, this formula is dedicated to TiO2 and is inapplicable to samples that contains more than two phases. The present research work proposed a simple method for quantifying the phase fraction of all types of nanomaterials that consist of two or more phases. Precision/ accuracy test carried out by multiplying the grand total intensity of all the diffraction peaks present in a sample with the value of the phase fraction of individual components showed that the proposed method gave precision values that were equivalent to the sum of the intensity of the peaks of each component. Whereas the S-M gave precision values that were significantly inconsistent with the sum of the intensity of the peaks of each component. The study showed that the proposed method was valid for a wide range of 2 values and can be deployed to obtain reasonable and reliable values of phase fraction that could assist to understand the material phase fraction-properties relationship.

The analytical solution of approximate natural frequencies for the free vibration of cylindrical shells of GFRP (glass fiber reinforced plastic) with Navier boundary conditions is presented using the Rayleigh-Ritz method, while the winding angle varies. Frequency variations for different vibration modes with certain shell's geometrical parameters are discussed. The effect of shell's geometrical parameters is also investigated on natural frequencies.

In the present paper results of definition of natural frequencies of simply supported-clamped thin cylindrical shells from the focused fiberglass considered as homogeneous monolithic anisotropic material are presented. Constants of elasticity of a material of a shell depend on an angle of winding of fiber glass. Natural frequencies of a shell are found in the assumption, that central lines have the spiral form. Constructions of dependences of frequencies from an angle of winding of fiber glass for various parameters of wave formation and the geometrical sizes of a shell are executed.

الملخص: أهداف البحث: تهدف هذه الدراسة إلى تحسين تكوين حبيبات هلامة ''ألجينات الأغاروز'' وعوامل التذويب الخاصة بها لاستخدامها المحتمل في نقل الخلايا الجذعية. طرق البحث: تم اختبار تركيزات مختلفة من الأغاروز والألجينات وكلورايد الكالسيوم لبناء حبيبات هلامة مائية. تم تسجيل معدل التحلل ونسبة الانتفاخ لكل عينة هلامة مائية. تم استخدام هلامة ''ألجينات الأغاروز'' المحسنة لتغليف الخلايا الجذعية من أسنان بشرية لبنية متساقطة (شيد). تم أيضًا إجراء تحسين عوامل الإذابة واختبارها باستخدام الخلايا المغلفة بالهلامة المائية. النتائج: تم إثبات أن التركيز المختار لمكونات هلامة ''ألجينات الأغاروز'' نجح في تغليف ''شيد'' والتي تظل قابلة للحياة حتى اليوم العاشر. تم تسجيل متوسط دقيقتين لتحلل الهلامة المائية التي تغلف ''شيد''، باستخدام عامل إذابة يتكون من 100 ملي سيترات الصوديوم و 100 ملي مولار من إيديتات الكالسيوم ثناي الصوديوم (إيديتا). تم تسجيل صلاحية خلية ''شيد'' التي تم إطلاقها بعد اليوم العاشر من التغليف بنسبة 29.1٪. الاستنتاجات: أوضحت الدراسة الحالية أن تركيزات كل من الأغاروز والألجينات وكلورايد الكالسيوم ترتبط بمعدل تحلل حبيبات الهلامة المائية ونسبة الانتفاخ. يمكن لـ ''شيد'' البقاء على قيد الحياة في بيئة هلامة مائية لمدة 10 أيام على الأقل دون تغيير وسط الاستزراع. يسمح تحسين عامل الذوبان بالتفكك المناسب لهيكل الهلامة المائية، مما يؤدي إلى إطلاق الخلايا الجذعية من حبيبات هلامة ''ألجينات الأغاروز'' بعد فترة النقل مع السماح للخلايا بالبقاء قابلة للحياة. Abstract: Hydrogels have potential uses in various biological applications because of their unique characteristics. Fine-tuning of agarose–alginate (Ag–Al) hydrogel components improves the mechanical characteristics of the final construct for cell encapsulation and transportation. Formulation of suitable dissolving agents may enable the release of encapsulated cells for further applications in laboratory or clinical settings. Objectives: This study aimed at optimizing the composition of Ag–Al hydrogel beads and their dissolving agents for potential use in the transportation of stem cells. Methods: Various agarose, alginate, and CaCl2 concentrations were tested to construct hydrogel beads. The degradation rate and swelling ratio of each hydrogel sample were recorded. The optimized Ag–Al hydrogels were used for encapsulation of stem cells from human exfoliated deciduous teeth (SHED). Optimization of dissolving agents was performed and tested with the hydrogel-encapsulated cells. Data were statistically analyzed in SPSS. Results: The selected concentration of Ag–Al hydrogels components was successfully demonstrated to encapsulate SHED, which remained viable until day 10. An average of 2 min was required for degradation of the hydrogel with encapsulated SHED by a dissolving agent consisting of 100 mM sodium citrate and 100 mM EDTA. The cell viability of SHED released after day 10 of encapsulation was 29.1%. Conclusion: Alteration of Ag-Al components has considerable influence on the mechanical properties of the constructed hydrogel. The feasibility of performing the optimized cell encapsulation protocol, as well as the dissolving step, may provide a useful guide for the transportation of viable cells between countries, for medical research.

The peak age of onset of hepatocellular carcinoma (HCC) is continually increasing worlwide. This study aims to evaluate whether there exists any significant difference in the clinicopathological features between younger- and elderly-HCC.1082 Consecutive patients with HCC who underwent liver resection at Liver Cancer Institute, Zhongshan Hospital, Fudan University from 1995 to 1998 were studied. The patients were divided into elderly-HCC (>/=65 years of age) and younger-HCC (< 65 years of age). Important clinicopathological features of the patients and postoperative survival rates were compared between these two groups. Among 1082 patients studied, 108 were elderly-HCC and 974 were younger-HCC. The resection rate of the elderly-HCC was significantly higher than that of the younger-HCC. The 1, 3 and 5-year survival rates of the elderly-HCC were not significantly different from those of the younger-HCC. Compared with the younger-HCC, the elderly-HCC had (1) less HBsAg-positive rate; (2) more frequent anti-HCV positivity ; (3) lower proportion with AFP value >/=400mug/dl; (4) a relatively small tumor diameter; (5) higher proportion of stage I-II patients; (6) a relatively low metastasis rate. However, there were no statistically significant differences in other clinicopathological features (including gender, symptoms, tumor number, tumor venous invasion, tumor differentiation, capsular formation, type of cirrhosis) between the two groups. There is a certain extent difference in clinicopathological features between elderly and younger-HCC patients, but the postoperative survival rate is comparable between the two groups. JNMA J Nepal Med Assoc. 2008 Jul-Sep;47(171):132-135.

Bulk La0.67Ca0.33MnO3 (LCMO) and NdGaO3 (NGO) have the same Pbnm symmetry but different orthorhombic lattice distortions, yielding an anisotropic strain state in the LCMO epitaxial film grown on the NGO(001) substrate. The films are optimally doped in a ferromagnetic-metal ground state, after being ex-situ annealed in oxygen atmosphere, however, they show strikingly an antiferromagnetic-insulating (AFI) transition near 250 K, leading to a phase separation state with tunable phase instability at the temperatures below. To explain this drastic strain effect, the films with various thicknesses were ex-situ annealed under various annealing parameters. We demonstrate that the ex-situ annealing can surprisingly improve the epitaxial quality, resulting in the films with true substrate coherency and the AFI ground state. And the close linkage between the film morphology and electronic phase evolution implies that the strain-mediated octahedral deformation and rotation could be assisted by ex-situ annealing, and moreover, play a key role in controlling the properties of oxide heterostructures.

Reactive Transport Models (RTMs) are essential tools for understanding and predicting intertwined ecohydrological and biogeochemical processes on land and in rivers. While traditional RTMs have focused primarily on subsurface processes, recent watershed-scale RTMs have integrated ecohydrological and biogeochemical interactions between surface and subsurface. These emergent, watershed-scale RTMs are often spatially explicit and require extensive data, computational power, and computational expertise. There is however a pressing need to create parsimonious models that require minimal data and are accessible to scientists with limited computational background. To that end, we have developed BioRT-HBV 1.0, a watershed-scale, hydro-biogeochemical RTM that builds upon the widely used, bucket-type HBV model known for its simplicity and minimal data requirements. BioRT-HBV uses the conceptual structure and hydrology output of HBV to simulate processes including advective solute transport and biogeochemical reactions that depend on reaction thermodynamics and kinetics. These reactions include, for example, chemical weathering, soil respiration, and nutrient transformation. The model uses time series of weather (air temperature, precipitation, and potential evapotranspiration) and initial biogeochemical conditions of subsurface water, soils, and rocks as input, and output times series of reaction rates and solute concentrations in subsurface waters and rivers. This paper presents the model structure and governing equations and demonstrates its utility with examples simulating carbon and nitrogen processes in a headwater catchment. As shown in the examples, BioRT-HBV can be used to illuminate the dynamics of biogeochemical reactions in the invisible, arduous-to-measure subsurface, and their influence on the observed stream or river chemistry and solute export. With its parsimonious structure and easy-to-use graphical user interface, BioRT-HBV can be a useful research tool for users without in-depth computational training. It can additionally serve as an educational tool that promotes pollination of ideas across disciplines and foster a diverse, equal, and inclusive user community., (© 2024 The Author(s). Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union.)

Extracellular histones are released in two major forms: free histones and nucleosomes (DNA-bound histones). However, little distinction has been made between these two forms of circulating extracellular histones. Our study detected increased circulating nucleosomes in acute lung injury patients. Further, our group identified nucleosomes as the leading form of extracellular histones compared to free histones in the plasma of COVID-19 patients, underscoring the necessity to reassess the forms of circulating histones and nucleosome contributions to immunopathology. Functionally, nucleosomes activated macrophages and induced inflammation in different organs. Mechanistically, we observed nucleosomes activating the NF-κB signaling, while inhibition of NF-κB by sulfasalazine attenuated nucleosome-induced macrophage activation. Taken together, our study indicates that extracellular histones are predominantly released as nucleosomes, playing a critical role in the inflammation of the lungs and other organs., (© 2024 The Author(s). The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Background: IgA nephropathy (IgAN) is intimately linked to mucosal immune responses, with nasopharyngeal and intestinal lymphoid tissues being crucial for its abnormal mucosal immunity. The specific pathogenic bacteria in these sites associated with IgAN, however, remain elusive. Our study employs 16S rRNA sequencing and machine learning (ML) approaches to identify specific pathogenic bacteria in these locations and to investigate common pathogens that may exacerbate IgAN., Methods: In this cross-sectional analysis, we collected pharyngeal swabs and stool specimens from IgAN patients and healthy controls. We applied 16SrRNA sequencing to identify differential microbial populations. ML algorithms were then used to classify IgAN based on these microbial differences. Spearman correlation analysis was employed to link key bacteria with clinical parameters., Results: We observed a reduced microbial diversity in IgAN patients compared to healthy controls. In the gut microbiota of IgAN patients, increases in Bacteroides , Escherichia-Shigella, and Parabacteroides , and decreases in Parasutterella , Dialister , Faecalibacterium , and Subdoligranulum were notable. In the respiratory microbiota, increases in Neisseria , Streptococcus, Fusobacterium , Porphyromonas , and Ralstonia , and decreases in Prevotella , Leptotrichia , and Veillonella were observed. Post-immunosuppressive therapy, Oxalobacter and Butyricoccus levels were significantly reduced in the gut, while Neisseria and Actinobacillus levels decreased in the respiratory tract. Veillonella and Fusobacterium appeared to influence IgAN through dual immune loci, with Fusobacterium abundance correlating with IgAN severity., Conclusions: This study revealing that changes in flora structure could provide important pathological insights for identifying therapeutic targets, and ML could facilitate noninvasive diagnostic methods for IgAN.