In this study, we investigated the application of Geographic Information Systems (GIS) for groundwater quality assessment through the integration of statistical models with soil and topographical ...data. Our primary objectives were to identify soil parameters and topographical attributes contributing to groundwater quality assessment and to evaluate the potential of geostatistics and GIS for spatial analysis of groundwater resources. Groundwater samples were collected from 43 agricultural wells, and surface soil layer samples (0-20 cm) were obtained near each well. We measured groundwater quality parameters and relevant soil properties. Our approach involved the utilization of multiple linear regression (MLR) and principal component regression (PCR), combined with topographical terrain attributes and soil data, for modeling groundwater electrical conductivity (GEC). Our findings revealed significant correlations between GEC and soil electrical conductivity (EC) (r = 0.89) as well as soil carbonate (CaCO.sub.3) (r = 0.68). Among the ten topographical attributes considered, the terrain wetness index (TWI) exerted the highest influence on GEC (r = 0.57), followed by the slope (r = -0.47). Further analysis demonstrated that the MLR model outperformed the PCR model in both the development and calibration datasets, with an achieved R.sup.2 value of 0.89 and a root mean square error (RMSE)of 150 muScm.sup.-1 for MLR, compared to an R.sup.2 of 0.85 and an RMSE of 170 muScm.sup.-1 for PCR when coupled with soil and attribute data for GEC prediction. The resulting GEC map generated from the MLR model displayed spatial variations, ranging from 605 muScm.sup.-1 in the northern region to 1275 muScm.sup.-1 in the central part of the study site. In conclusion, our study demonstrated the effectiveness of combining statistical modeling with geostatistics and GIS for groundwater quality assessment, providing valuable insights for resource management and environmental planning.
Robust and efficient detection of an infrared (IR) small target is very important in the IR search and track system. Based on the contrast mechanism of the human visual system, an IR small target ...detection method with high detection rate, low false alarm rate, and short processing time is proposed in this letter. This method consists of two stages. At the first stage, with the top-hat filter and an adaptive threshold operation based on the constant false alarm rate applied to the original image, the suspicious target regions are obtained. In this way, the computing time of the following steps would be reduced a lot; meanwhile, the desired and predictable detection probability with the constant false alarm probability is maintained. At the second stage, we first define a new efficient local contrast measure between the target and the background, and the local self-similarity of an image is introduced to calculate the local saliency map. With the combination of the local self-similarity and local contrast, an efficient saliency map is obtained, which cannot only increase the signal-to-clutter ratio but also suppress residual clutter simultaneously. Then, a simple threshold operation on the saliency map is used to get the true targets. Experimental results indicate that the proposed method is superior in detection rate, false alarm rate, and processing time compared with the contrast algorithms, and it is an efficient method for IR small target detection in a complex background.
Lipids and lipid metabolism play crucial roles in regulating T cell function and are tightly related to the establishment of immune memory. It is reported that tumor-infiltrating CD8
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T lymphocytes ...(CD8
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TILs) burn fats to restore their impaired effector function due to the lack of glucose. Conversely, fatty acids (FAs) and cholesterol in the tumor microenvironment (TME) drive the CD8
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TILs dysfunction. The origin of dysfunctional CD8
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TILs shares important features with memory T cell’s precursor, but whether lipids and/or lipid metabolism reprogramming directly influence the memory plasticity of dysfunctional CD8
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TILs remains elusive. It is necessary to understand the interplay between cellular lipid metabolism and dysfunction of CD8
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TILs in the case of targeting T cell’s metabolism to synergize cancer immunotherapy. Therefore, in this review, we summarize the latest research on CD8
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TILs lipid metabolism, evaluate the impacts of lipids in the TME to CD8
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TILs, and highlight the significance of promoting memory phenotype cell formation by targeting CD8
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T cells lipid metabolism to provide longer duration of cancer immunotherapy efficacy.
► We propose an approach to evaluate the fatigue reliabilities of steel bridge details. ► A probabilistic traffic model is developed based on weigh-in-motion data. ► Probabilistic finite element ...analyses are made to obtain the fatigue reliabilities. ► The calculated results match well with those obtained from monitored stress data.
An advanced traffic load model is developed based on weigh-in-motion data. This model takes into account the uncertainties associated with the number of axles, axle weights, axle spacing and transversal position of vehicles. Combined with the traffic load model, a probabilistic finite element analysis approach is proposed to evaluate the time-dependent fatigue reliability levels of steel bridge details. The calculated results are in agreement with those obtained from monitored data. The proposed methodology can be used as a tool accompanying a monitoring program to obtain the fatigue reliability levels associated with the fatigue sensitive bridge details that are not monitored.
Technology accumulation plays a vital role in research and development (R&D) activities. This paper used technology accumulation as the threshold variable to construct a dynamic panel threshold model ...to explore the technology accumulation threshold effect of independent R&D on innovation performance of China's pharmaceutical manufacturing industry over the period 1995~2019. The results show that the independent R&D of China's pharmaceutical manufacturing industry had a significant promotion effect on innovation performance. However, it is constrained by the level of technology accumulation, showing a significant double threshold effect of technology accumulation. A moderate level of technology accumulation was more conducive to independent R&D to drive innovation performance, while lower or higher technology accumulation will weaken independent R&D promotion on innovation performance. This study provided insights for policymakers and managers in making effective innovation strategies.
While the catalog of mammalian transcripts and their expression levels in different cell types and disease states is rapidly expanding, our understanding of transcript function lags behind. We ...present a robust technology enabling systematic investigation of the cellular consequences of repressing or inducing individual transcripts. We identify rules for specific targeting of transcriptional repressors (CRISPRi), typically achieving 90%–99% knockdown with minimal off-target effects, and activators (CRISPRa) to endogenous genes via endonuclease-deficient Cas9. Together they enable modulation of gene expression over a ∼1,000-fold range. Using these rules, we construct genome-scale CRISPRi and CRISPRa libraries, each of which we validate with two pooled screens. Growth-based screens identify essential genes, tumor suppressors, and regulators of differentiation. Screens for sensitivity to a cholera-diphtheria toxin provide broad insights into the mechanisms of pathogen entry, retrotranslocation and toxicity. Our results establish CRISPRi and CRISPRa as powerful tools that provide rich and complementary information for mapping complex pathways.
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•CRISPRi and CRISPRa provide complementary information for mapping complex pathways•CRISPRi/a expression series (up to ∼1,000-fold) reveal how gene dose controls function•CRISPRi provides strong (typically 90%–99%) knockdown with minimal off-target effects•Genome-scale screens elucidate pathways controlling cholera/diphtheria toxicity
Genome-scale-specific targeting of transcriptional repressors (CRISPRi) and activators (CRISPRa) to endogenous genes via endonuclease-deficient Cas9 have been applied to growth and toxin-resistance screens, establishing CRISPRi and CRISPRa as powerful tools that provide rich and complementary information.
Traditional Chinese medicine has become an important pillar of “Healthy China” and the national medical system in recent years. Due to the wide range of raw materials in traditional Chinese medicinal ...materials (TCMM), the issue of metals has attracted more and more attention. In this paper, a comprehensive review of public reports on metals in TCMM in recent decades was conducted. From a total of 1969 reported articles, a total of 296 research reports on metals in TCMM were screened. The 296 reports involved 255 species in 85 families, with a total of 274 medicinal materials. These TCMM were divided into taproot-type, leaf-type, flower and fruit-type, herba-type, stem-type and bark-type medicinal materials according to the medicinal parts. The content of five metals lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr) in these TCMM was noted, and the distribution rules for metals were analyzed. The results showed that: (1) For the distribution of metals in different medicinal parts, Pb was mainly distributed in leaves; Cd was mainly distributed in flowers and fruits, stems and leaves; Hg was mainly distributed in barks; As was mainly distributed in stems; Cr was mainly distributed in stems, flowers and fruits. (2) The areas with the highest risk of metal residues were the Qinghai-Tibet Plateau, south China, and southwest China. (3) Among all types of TCMM, herba-type medicinal materials had the highest risk of metal content. (4) Combined with the pharmacopoeia metal limit standards implemented in 2019, the exceeding rate of Pb in TCMM was the highest, with a maximum value of 37.67%; among the six major types of TCMM, the medicinal materials with the highest exceeding rate were herba-type medicinal materials, among which Hg had the highest exceeding rate of 23.08%; in terms of medicinal parts, the highest exceeding rate of metals was in leaf-type medicinal materials, among which Pb had the highest exceeding rate of 37.67%. On the whole, the situation in regard to metal residues in TCMM was acceptable, but it cannot be ignored. It needed to be paid attention to in the industrialization and management of TCMM.
•Metals in TCMM varied with different parts of the plant.•The risk of metal residues was highest in southern regions in China.•Herba-type medicinal materials had the highest risk of metal content.•The metal content of TCMM generally showed an increasing trend.•The safety of metals in TCMM is acceptable, but it cannot be ignored.
In this paper, we review the contributions to date for analyzing the newsvendor problem. Our focus is on examining the specific extensions for analyzing this problem in the context of modeling ...customer demand, supplier costs, and the buyer risk profile. More specifically, we analyze the impact of market price, marketing effort, and stocking quantity on customer demand; how supplier prices can serve as a coordination mechanism in a supply chain setting; integrating alternative supplier pricing policies within the newsvendor framework; and how the buyer’s risk profile moderates the newsvendor order quantity decision. For each of these areas, we summarize the current literature and develop extensions. Finally, we also propose directions for future research.
The combination of chemotherapy and photodynamic therapy (PDT) has promising potential in the synergistic treatment of cancer. However, chemotherapy and photodynamic synergistic therapy are impeded ...by uncontrolled chemotherapeutics release behavior, targeting deficiencies, and hypoxia‐associated poor PDT efficacy in solid tumors. Here, a platinum nanozyme (PtNP) loaded reactive oxygen species (ROS)‐responsive prodrug nanoparticle (CPT‐TK‐HPPH/Pt NP) is created to overcome these limitations. The ROS‐responsive prodrug consists of a thioketal bond linked with camptothecin (CPT) and photosensitizer‐2‐(1‐hexyloxyethyl)‐2‐devinyl pyropheophorbide‐a (HPPH). The PtNP in CPT‐TK‐HPPH/Pt NP can efficiently catalyze the decomposition of hydrogen peroxide (H2O2) into oxygen to relieve hypoxia. The production of oxygen can satisfy the consumption of HPPH under 660 nm laser irradiation to attain the on‐demand release of CPT and ensure enhanced photodynamic therapy. As a tumor diagnosis agent, the results of photoacoustic imaging and fluorescence imaging for CPT‐TK‐HPPH/Pt NP exhibit desirable long circulation and enhanced in vivo targeting. CPT‐TK‐HPPH/Pt NPs effectively inhibit tumor proliferation and growth in vitro and in vivo. CPT‐TK‐HPPH/Pt NP, with its excellent ROS‐responsive drug release behavior and enhanced PDT efficiency can serve as a new cancer theranostic agent, and will further promote the research of chemophotodynamic synergistic cancer therapy.
The platinum nanozyme (PtNP) loaded reactive oxygen species‐responsive prodrug nanoparticle (CPT‐TK‐HPPH/Pt NP) which could achieve the “on‐demand” release of CPT and relieve hypoxia to enhance photodynamic therapy efficiency, exhibits desirable long circulation and effectively inhibits tumor proliferation and growth in vitro and in vivo, has great promising potential in chemophotodynamic synergistic cancer therapy.
Functional genomics efforts face tradeoffs between number of perturbations examined and complexity of phenotypes measured. We bridge this gap with Perturb-seq, which combines droplet-based ...single-cell RNA-seq with a strategy for barcoding CRISPR-mediated perturbations, allowing many perturbations to be profiled in pooled format. We applied Perturb-seq to dissect the mammalian unfolded protein response (UPR) using single and combinatorial CRISPR perturbations. Two genome-scale CRISPR interference (CRISPRi) screens identified genes whose repression perturbs ER homeostasis. Subjecting ∼100 hits to Perturb-seq enabled high-precision functional clustering of genes. Single-cell analyses decoupled the three UPR branches, revealed bifurcated UPR branch activation among cells subject to the same perturbation, and uncovered differential activation of the branches across hits, including an isolated feedback loop between the translocon and IRE1α. These studies provide insight into how the three sensors of ER homeostasis monitor distinct types of stress and highlight the ability of Perturb-seq to dissect complex cellular responses.
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•Perturb-seq allows parallel screening with rich phenotypic output from single cells•Simultaneous delivery and identification of up to three CRISPR perturbations•Genome-scale screens dissect the mammalian unfolded protein response•Analytical methods separate perturbation responses from confounding effects
A strategy for barcoding CRISPR-mediated perturbations allows pooled expression profiling via single-cell RNA sequencing. Application to the mammalian unfolded protein response then enabled systematic delineation of the transcriptional arms of the response and functional clustering of genes affecting ER homeostasis.
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