Correlating Buffering Agents' Premier pH with Interface Stability Toward Long-Term Zn Metal Anodes.

Aqueous solvents in Zn metal batteries inevitably induces hydrogen evolution reactions (HER) due to fluctuating pH levels in electrolytes, leading to severe side reactions and dendrite growth. To address these challenges, buffering agents have been recently proposed as a solution to maintain constant electrolyte pH values upon cycling. Nonetheless, the critical role of buffering additives' premier pH in determining interface stability is largely overlooked. Herein, two types of buffering agents, single amphoteric and conjugate acid-base pairs, are employed to correlate their initial pHs with the interface stability. Based on the observations, the lifetime of Zn metal anodes initially increases and then decreases as the initial pH level goes up from 2.0 to 5.0, with an optimal lifetime at pH 3.3 for both buffering agent categories. This phenomenon lies in ample H+ in low pH and rich OH- in high pH, leading to either severe HER or by-products passivation layer. The optimized pH allows cells to deliver a high average Coulombic efficiency of 99.61% over 1500 cycles at a large current density of 5 mA cm-2 , which is significantly superior to 345 cycles achieved in the pristine electrolyte. Furthermore, this enhanced interface enables stable Zn/activated carbon full batteries over 15 000 cycles.

Developing a Predictive Model for Minimal or Mild Endometriosis as a Clinical Screening Tool in Infertile Women: Uterosacral Tenderness as a Key Predictor.

STUDY OBJECTIVE: To develop a noninvasive predictive model based on patients with infertility for identifying minimal or mild endometriosis. DESIGN: A retrospective cohort study. SETTING: This study was conducted at a tertiary referral center. PATIENTS: A total of consecutive 1365 patients with infertility who underwent laparoscopy between January 2013 and August 2020 were divided into a training set (n = 910) for developing the predictive model and a validation set (n = 455) to confirm the model's prediction efficiency. The patients were randomly assigned in a 2:1 ratio. INTERVENTIONS: Sensitivities, specificities, area under the curve, the Hosmer-Lemeshow goodness of fit test, Net Reclassification Improvement index, and Integrated Discrimination Improvement index were evaluated in the training set to select the optimum model. In the validation set, the model's discriminations, calibrations, and clinical use were tested for validation. MEASUREMENTS AND MAIN RESULTS: In the training set, there were 587 patients with minimal or mild endometriosis and 323 patients without endometriosis. The combination of clinical parameters in the model was evaluated for both statistical and clinical significance. The best-performing model ultimately included body mass index, dysmenorrhea, dyspareunia, uterosacral tenderness, and serum cancer antigen 125 (CA-125). The nomogram based on this model demonstrated sensitivities of 87.7% and 93.3%, specificities of 68.6% and 66.4%, and area under the curve of 0.84 (95% confidence interval 0.81-0.87) and 0.85 (95% confidence interval 0.80-0.89) for the training and validation sets, respectively. Calibration curves and decision curve analyses also indicated that the model had good calibration and clinical value. Uterosacral tenderness emerged as the most valuable predictor. CONCLUSION: This study successfully developed a predictive model with high accuracy in identifying infertile women with minimal or mild endometriosis based on clinical characteristics, signs, and cost-effective blood tests. This model would assist clinicians in screening infertile women for minimal or mild endometriosis, thereby facilitating early diagnosis and treatment.

Examining Concentration-Reliant Zn Deposition/Stripping Behavior in Organic Alcohol/Sulfones-Modified Aqueous Electrolytes.

The practical application of Zn metal anodes in electronic devices is hindered by dendrite growth and parasitic reactions. Electrolyte optimization, particularly the introduction of organic co-solvents, is widely used to circumvent these challenges. Various organic solvents in a wide range of concentrations have been reported; however, their influences and corresponding working mechanisms at different concentrations are largely unexplored in the same organic species. Herein, economical, low-flammable ethylene glycol (EG) is used as a model co-solvent in aqueous electrolytes to examine the relationship between its concentration, anode-stabilizing effect, and mechanism. Two maximal values are observed for the lifetime of Zn/Zn symmetric batteries under EG concentrations from 0.05 vol% to 48 vol%. Zn metal anodes can stably run for over 1700 h at a low EG content (0.25 vol%) and high EG content (40 vol%). Based on the complementary experimental and theoretical calculations, the enhancements in low- and high-content EG are ascribed to the specific surface adsorption for suppressed dendrite growth and the regulated solvation structure for inhibited side reactions, respectively. Intriguingly, a similar concentration-reliant bimodal phenomenon is observed in other low-flammable organic solvents (e.g., glycerol and dimethyl sulfoxide), thereby suggesting universality of this study and providing insight into electrolyte optimization.

Clinical evaluation of deep learning-based automatic clinical target volume segmentation: a single-institution multi-site tumor experience.

PURPOSE: The large variability in tumor appearance and shape makes manual delineation of the clinical target volume (CTV) time-consuming, and the results depend on the oncologists' experience. Whereas deep learning techniques have allowed oncologists to automate the CTV delineation, multi-site tumor analysis is often lacking in the literature. This study aimed to evaluate the deep learning models that automatically contour CTVs of tumors at various sites on computed tomography (CT) images from objective and subjective perspectives. METHODS AND MATERIALS: 577 patients were selected for the present study, including nasopharyngeal (n = 34), esophageal (n = 40), breast-conserving surgery (BCS) (left-sided, n = 71; right-sided, n = 71), breast-radical mastectomy (BRM) (left-sided, n = 43; right-sided, n = 37), cervical (radical radiotherapy, n = 45; postoperative, n = 85), prostate (n = 42), and rectal (n = 109) carcinomas. Manually delineated CTV contours by radiation oncologists are served as ground truth. Four models were evaluated: Flexnet, Unet, Vnet, and Segresnet, which are commercially available in the medical product "AccuLearning AI model training platform". The data were divided into the training, validation, and testing set at a ratio of 5:1:4. The geometric metrics, including Dice Similarity Coefficient (DSC) and Hausdorff Distance (HD), were calculated for objective evaluation. For subjective assessment, oncologists rated the segmentation contours of the testing set visually. RESULTS: High correlations were observed between automatic and manual contours. Based on the results of the independent test group, most of the patients achieved satisfactory quantitative results (DSC > 0.8), except for patients with esophageal carcinoma (DSC: 0.62-0.64). The subjective review indicated that 82.65% of predicted CTVs scored either as clinically accepting (8.68%) or requiring minor revision (73.97%), and no patients were scored as rejected. CONCLUSION: This experimental work demonstrated that auto-generated contours could serve as an initial template to help oncologists save time in CTV delineation. The deep learning-based auto-segmentations achieve acceptable accuracy and show the potential to improve clinical efficiency for radiotherapy of a variety of cancer.

Molecular Simulation Study on the Interaction between Porcine CR1-like and C3b.

The molecular basis of porcine red blood cell immune adhesion function stems from the complement receptor type 1-like (CR1-like) on its cell membrane. The ligand for CR1-like is C3b, which is produced by the cleavage of complement C3; however, the molecular mechanism of the immune adhesion of porcine erythrocytes is still unclear. Here, homology modeling was used to construct three-dimensional models of C3b and two fragments of CR1-like. An interaction model of C3b-CR1-like was constructed by molecular docking, and molecular structure optimization was achieved using molecular dynamics simulation. A simulated alanine mutation scan revealed that the amino acids Tyr761, Arg763, Phe765, Thr789, and Val873 of CR1-like SCR 12-14 and the amino acid residues Tyr1210, Asn1244, Val1249, Thr1253, Tyr1267, Val1322, and Val1339 of CR1-like SCR 19-21 are key residues involved in the interaction of porcine C3b with CR1-like. This study investigated the interaction between porcine CR1-like and C3b using molecular simulation to clarify the molecular mechanism of the immune adhesion of porcine erythrocytes.

EZH2 upregulates the expression of MAPK1 to promote intervertebral disc degeneration via suppression of miR-129-5p.

BACKGROUND: This study was designed to verify whether enhancer of zeste homolog 2 (EZH2) affects intervertebral disc degeneration (IVDD) development through regulation of microRNA (miR)-129-5p/MAPK1. METHODS: Initially, we collected lumbar nucleus pulposus (NP) tissue samples from patients with juvenile idiopathic scoliosis (n = 14) and IVDD (n = 34). We measured the expression of related genes in clinical IVDD tissues and a lipopolysaccharide (LPS)-induced NP cell model. After loss- and gain-of-function assays, NP cell proliferation and senescence were examined. The targeting relationship between miR-129-5p and MAPK1 was explored by dual luciferase reporter gene and RNA immunoprecipitation (RIP) assays. The enrichment of EZH2 and H3K27me3 in miR-129-5p promoter was verified by chromatin immunoprecipitation (ChIP). Finally, an IVDD rat model was established to test the effects of transduction with lentiviral vector carrying miR-129-5p agomir and/or oe-EZH2 in vivo. RESULTS: miR-129-5p was underexpressed, and EZH2 and MAPK1 levels were overexpressed in lumbar nucleus pulposus from human IVDD patients and in LPS-induced NP cells. miR-129-5p overexpression or silencing of MAPK1 promoted proliferation of NP cells, while inhibiting their senescence. EZH2 inhibited miR-129-5p through H3K27me3 modification in the miR-129-5p promoter. miR-129-5p could target the downregulation of MAPK1 expression. EZH2 overexpression increased the release of inflammatory factors and cell senescence factors, which was reversed by miR-129-5p agomir in vivo. CONCLUSIONS: Taken together, EZH2 inhibits miR-129-5p through H3K27me3 modification, which upregulates MAPK1, thereby promoting the development of IVDD.

FOXG1 Contributes Adult Hippocampal Neurogenesis in Mice.

Strategies to enhance hippocampal precursor cells efficiently differentiate into neurons could be crucial for structural repair after neurodegenerative damage. FOXG1 has been shown to play an important role in pattern formation, cell proliferation, and cell specification during embryonic and early postnatal neurogenesis. Thus far, the role of FOXG1 in adult hippocampal neurogenesis is largely unknown. Utilizing CAG-loxp-stop-loxp-Foxg1-IRES-EGFP (Foxg1fl/fl), a specific mouse line combined with CreAAV infusion, we successfully forced FOXG1 overexpressed in the hippocampal dentate gyrus (DG) of the genotype mice. Thereafter, we explored the function of FOXG1 on neuronal lineage progression and hippocampal neurogenesis in adult mice. By inhibiting p21cip1 expression, FOXG1-regulated activities enable the expansion of the precursor cell population. Besides, FOXG1 induced quiescent radial-glia like type I neural progenitor, giving rise to intermediate progenitor cells, neuroblasts in the hippocampal DG. Through increasing the length of G1 phase, FOXG1 promoted lineage-committed cells to exit the cell cycle and differentiate into mature neurons. The present results suggest that FOXG1 likely promotes neuronal lineage progression and thereby contributes to adult hippocampal neurogenesis. Elevating FOXG1 levels either pharmacologically or through other means could present a therapeutic strategy for disease related with neuronal loss.

5-Demethoxy-10'-ethoxyexotimarin F, a New Coumarin with MAO-B Inhibitory Potential from Murraya exotica L.

Rutaceae plants are known for being a rich source of coumarins. Preliminary molecular docking showed that there was no significant difference for coumarins in Clausena and Murraya, both of which had high scoring values and showed good potential inhibitory activity to the MAO-B enzyme. Overall, 32 coumarins were isolated from Murraya exotica L., including a new coumarin 5-demethoxy-10'-ethoxyexotimarin F (1). Their structures were elucidated on the basis of a comprehensive analysis of 1D and 2D NMR and HRMS spectroscopic data, and the absolute configurations were assigned via a comparison of the specific rotations and the ECD exciton coupling method. The potential of new coumarin (1) as a selective inhibitor of MAO-B was initially evaluated through molecular docking and pharmacophore studies. Compound (1) showed selectivity for the MAO-B isoenzyme and inhibitory activity in the sub-micromolar range with an IC50 value of 153.25 ± 1.58 nM (MAO-B selectivity index > 172).

Correlation between Electrolyte Chemistry and Solid Electrolyte Interphase for Reversible Ca Metal Anodes.

The development of rechargeable Ca metal batteries (RCMBs) is hindered by the Ca2+ passivating solid electrolyte interphases (SEIs). The cation solvation structure dictated by electrolyte chemistry plays a critical role in the SEIs properties. While a relatively weak cation-solvent binding is preferred in Li metal anodes to promote anion-derived SEIs, we demonstrate an enhanced Ca deposition/stripping reversibility under a strong cation-solvent interaction, which is materialized in strongly-solvating solvent and highly-dissociated salt combinations. Such electrolyte formulations benefit the formation of solvent-occupied solvation structure and minimize the anion reduction, resulting in organic-rich/CaF2 -poor SEIs for reversible Ca metal anodes. Furthermore, RCMBs paired with an organic cathode using the optimized electrolytes are demonstrated as a proof-of-concept. Our work reveals the paradigm shift in SEIs design for Ca metal anodes, opening up new opportunities for emerging RCMBs.

Determination of Vanadium Isotope Compositions in Carbonates Using an Fe Coprecipitation Method and MC-ICP-MS.

Vanadium isotope compositions (δ(51V)) in marine carbonates are a potential proxy to trace global redox states of ancient oceans. Although high-precision δ(51V) analyses are available for many geological materials, carbonate-hosted δ(51V) data have not been reported yet due to extremely high matrix elements and low V contents (generally below 10 µg g-1). In this study, we developed an Fe coprecipitation method combined with an Fe column to preconcentrate V from the major matrix elements and subsequent four-step chromatographic procedures to further purify V in carbonates. The δ(51V) values were measured using a sample-standard bracketing method by MC-ICP-MS. The robustness of this method was assessed by analyzing element-doped and matrix-spiked synthetic carbonate solutions containing an in-house δ(51V) standard, USTC-V. The mean δ(51V) value of the synthetic carbonate solutions (0.06 ± 0.08‰; 2SD, n = 33) is in good agreement with the recommended value of the USTC-V relative to the Oxford AA solution (0.07 ± 0.08‰; 2SD, n = 347). In addition, the consistency in the δ(51V) value of the igneous carbonatite standard, COQ-1, which was processed in parallel with the whole purification (-0.48 ± 0.04‰; 2SD, n = 3) and a four-step chromatographic procedure (-0.43 ± 0.08‰; 2SD, n = 3), further validates the robustness of our method. For the first time, we obtained δ(51V) values of four carbonate reference materials: JDo-1, -0.56 ± 0.09‰ (2SD, n = 27); JLs-1, -0.61 ± 0.14‰ (2SD, n = 33); GBW07217a, -0.79 ± 0.09‰ (2SD, n = 6); GBW07214a, -0.51 ± 0.13‰ (2SD, n = 48). The long-term external precision of carbonate-hosted δ(51V) analyses is better than ±0.14‰ (2SD). Our method can be applied to measure carbonate-hosted δ(51V) to trace the evolution in global marine redox states throughout the Earth's history.

Next-generation sequencing combined with serological tests based pathogen analysis for a neurocysticercosis patient with a 20-year history:a case report.

BACKGROUND: Neurocysticercosis (NCC) is the most common helminthic infection of the central nervous system (CNS) caused by the larval stage of Taenia solium. Accurate and early diagnosis of NCC remains challenging due to its heterogeneous clinical manifestations, neuroimaging deficits, variable sensitivity, and specificity of serological tests. Next-generation sequencing (NGS)-based pathogen analysis in patient's cerebrospinal fluid (CSF) with NCC infection has recently been reported indicating its diagnostic efficacy. In this case study, we report the diagnosis of a NCC patient with a symptomatic history of over 20 years using NGS analysis and further confirmation of the pathology by immunological tests. CASE PRESENTATION: This study reports the clinical imaging and immunological features of a patient with a recurrent headache for more than 20 years, which worsened gradually with the symptom of fever for more than 7 years and paroxysmal amaurosis for more than 1 year. By utilizing NGS technique, the pathogen was detected in patient's CSF, and the presence of Taenia solium-DNA was confirmed by a positive immunological reaction to cysticercus IgG antibody in CSF and serum samples. The symptoms of the patient were alleviated, and the CSF condition was improved substantially after the anti-helminthic treatment. CONCLUSIONS: This study suggests that combining CSF NGS with cysticercus IgG testing may be a highly promising approach for diagnosing the challenging cases of NCC. Further studies are needed to evaluate the parasitic DNA load in patients' CSF for the diagnosis of disease severity, stage, and monitoring of therapeutic responses.

Integrated Analysis of Quantitative Proteome and Transcriptional Profiles Reveals the Dynamic Function of Maternally Expressed Proteins After Parthenogenetic Activation of Buffalo Oocyte.

Maternal-effect genes are especially critical for early embryonic development after fertilization and until massive activation of the embryonic genome occurs. By applying a tandem mass tag (TMT)-labeled quantitative proteomics combined with RNA sequencing approach, the proteome of the buffalo was quantitatively analyzed during parthenogenesis of mature oocytes and the two-cell stage embryo. Of 1908 quantified proteins, 123 differed significantly. The transcriptome was analyzed eight stages (GV, MII, 2-cell, 4-cell, 8-cell, 16-cell, morula, blastocyst) of Buffalo using the RNA sequencing approach, and a total of 3567 unique genes were identified to be differently expressed between all consecutive stages of pre-implantation development. Validation of proteomics results (TUBB3, CTNNA1, CDH3, MAP2K1), which are involved in tight junction and gap junction, revealing that the maternal expression of the proteins possibly plays a role in the formation of cellular junctions firstly after parthenogenetic activation. Correlation and hierarchical analyses of transcriptional profiles and the expression of NPM2 and NLRP5 mRNA of buffalo in vitro developed oocytes and parthenogenetic embryos indicated that the "maternal-to-zygotic transition" (MZT) process might exist in the model of parthenogenesis, which is similar to a normally fertilized embryo, and may occur between the 8-cell to 16-cell stage. These data provide a rich resource for further studies on maternal proteins and genes and are conducive to improving nuclear transfer technology.

Maternal transcription profiles at different stages for the development of early embryo in buffalo.

Maternal mRNAs deposited in the egg during oogenesis are critical during the development of early embryo, before the activation of the embryonic genome. However, there is little known about the dynamic expression of maternally expressed genes in mammals. In this study, we made buffalo parthenogenesis as our research model to analyse maternal transcription profiles of pre-implantation embryo in buffalo using RNA sequencing. In total, 3,567 unique genes were detected to be differentially expressed among all constant stages during early embryo development (FPKM > 0). Interestingly, a total of 10,442 new genes were discovered in this study, and gene ontology analysis of the new differentially expressed genes indicated that the new genes have a wide cellular localization and are involved in many molecular functions and biological processes. Moreover, we identified eight clusters that were only highly expressed in a particular developmental stage and enriched a number of GO terms and KEGG pathways that were related to specific stage. Furthermore, we identified 1,530 hub genes (or key members) from the maternally expressed gene networks, and these hub genes were involved in 11 stage-specific modules. After visualization using Cytoscape 3.2.1 software, we obtained complex interaction network of hub genes, indicating the highly efficient cooperation between genes during the development in buffalo embryos. Further research of these genes will greatly deepen our understanding of embryo development in buffalo. Collectively, this research lays the foundation for future studies on the maternal genome function, buffalo nuclear transfer and parthenogenetic embryonic stem cells.

Free Amino Group-Directed γ-C(sp3)-H Arylation of α-Amino Esters with Diaryliodonium Triflates by Palladium Catalysis.

Free amino group-directed C(sp3)-H functionalization of aliphatic amines is a fundamental challenge in synthetic organic chemistry. Also, the NH2-directed C(sp3)-H functionalization of α-amino acids and their derivatives remains barely explored. With palladium as the catalyst and Ag2O as the additive, we developed the first NH2-directed γ-C(sp3)-H arylation of α-amino esters with diaryliodonium triflates for the construction of synthetically useful γ-aryl-α-amino esters, and the result of the KIE study suggested that the catalytic reaction involved an irreversible C-H cleavage as the rate-determining step.

A case report: 1-year follow-up of cerebral sparganosis mansoni with a stroke-like onset.

BACKGROUND: Sparganosis mansoni is a parasitic disease caused by infection with the larvae of Spirometra spp. tapeworms. Its clinical manifestations and severity depend on the migration and the location of the parasites. The proportion of cerebral sparganosis in all Spirometra mansoni infections is 13.5% in Thailand and 12.4% in China. In the clinical setting, cerebral sparganosis is often misdiagnosed due to atypical characteristics, irregular intracranial location, and atypical epidemiology. CASE PRESENTATION: The patient in the case study suffered from an acute paroxysmal attack of lateral numbness, accompanied with focal epilepsy. He was admitted to the neurology department as a stroke patient but was later diagnosed with cerebral sparganosis mansoni following lab and radiology investigations. He was fully recovered and free of Spirometra mansoni one year after initial consultation following several courses of oral praziquantel. The current report focuses on the diagnosis, treatment and follow up of this patient. CONCLUSIONS: A case of cerebral sparganosis mansoni with a stroke-like onsetsuggests that in the clinical diagnosis, neurologists should pay attention to brain lesions and look out for the possibility of neuroparasitic infections when dealing with patients with stroke-like onset accompanied by epilepsy. Detections of relevant antibodies in blood and cerebrospinal fluid may be necessary. The combination of the epidemiological history, clinical manifestations, detection of parasite antibody, head radiology, pathological biopsy, and identification of parasites will help us in diagnosis and differential diagnosis.

[Establishment of evaluation system on food safety management capacity for food production enterprises by Delphi method].

OBJECTIVE: To construct an evaluation indicator system on food safety management capacity for food production enterprises by Delphi method, and to provide a scientific theoretical framework for food safety management capacity for food enterprises.
 Methods: A framework for the evaluation system on food safety management capabilities was established and experts in relevant fields were invited to conduct 2 rounds of expert consultation. Indicators were selected and determined based on expert opinions and statistical analysis results. The hierarchical model was constructed by the analytic hierarchy process to determine the weight coefficients of each indicator.
 Results: The positive coefficients of the two rounds of expert consultation were 84% and 100%, and the coefficient of experts' authority was 0.826. The coordination coefficients of the indicators in the first round of consultation were 0.439, 0.323 and 0.324, and they were 0.607, 0.351, and 0.368 in the second round, respectively, with statistically significant differences (P<0.001). The evaluation index system of food safety management capacity for food production enterprises was established after the two rounds of expert consultation, and the system consisted of 5 indicators for the first level, 18 indicators for the second level and 32 indicators for the third level, with corresponding weights. 
 Conclusion: The enthusiasm, authority and concordance of experts during this consultation are good, and the selected indicators are reasonable and comprehensive, which can provide a basis for the evaluation of food safety management capabilities for food enterprises.

Corticosterone-Induced Lipogenesis Activation and Lipophagy Inhibition in Chicken Liver Are Alleviated by Maternal Betaine Supplementation.

Background: We have shown previously that in ovo betaine injection can prevent nonalcoholic fatty liver induced by glucocorticoid exposure in chickens; yet it remains unknown whether feeding betaine to laying hens may exert similar effects in their progeny. Objective: In this study, we fed laying hens a betaine-supplemented diet, and the progeny were later exposed chronically to corticosterone (CORT) to test hepatoprotective effects and further elucidate underlying mechanisms. Methods: Rugao yellow-feathered laying hens (n = 120) were fed a basal (control, C) diet or a 0.5% betaine-supplemented (B) diet for 28 d before their eggs were collected for incubation. At 49 d of age, male chickens selected from each group were daily injected subcutaneously with solvent (15% ethanol; vehicle, VEH) or CORT (4.0 mg/kg body mass) for 7 d to establish a fatty liver model. Chickens in the 4 groups (C-VEH, C-CORT, B-VEH, and B-CORT) were killed at day 57. Plasma and hepatic triglyceride (TG) concentrations, as well as the hepatic expression of genes involved in lipogenesis and lipophagy, were determined. Results: CORT induced a 1.6-fold increase in the plasma TG concentration (P < 0.05) and a 1.8-fold increment in the hepatic TG concentration (P < 0.05), associated with activation of lipogenic genes (70-780%). In contrast, lipophagy and mitochondrial ß-oxidation genes were inhibited by 30-60% (P < 0.05) in CORT-treated chickens. These CORT-induced changes were completely normalized by maternal betaine supplementation or were partially normalized to intermediate values that were significantly different from those in the C-VEH and C-CORT groups. These effects were accompanied by modifications in CpG methylation and glucocorticoid receptor binding to the promoters of major lipogenic and lipophagic genes (P < 0.05). Conclusions: These results indicate that maternal betaine supplementation protects male juvenile chickens from CORT-induced TG accumulation in the liver via epigenetic modulation of lipogenic and lipophagic genes.

Simple and rapid UPLC-MS/MS method for quantification of entecavir in human plasma: Application to a bioequivalence study
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A simple and fast ultra-performance liquid chromatography-tandem mass spectrometry method was developed and validated to determine entecavir in human plasma with the stable isotopically labeled internal standard entecavir-13C215N. Samples (100 µL each) were pretreated by protein precipitation with methanol, and then separated on an ACQUITY UPLC BEH C18 analytical column (2.1 × 50 mm, 1.7 µm) with a simple isocratic elution. The detection was operated by a positive ionization electrospray mass spectrometry in multiple reaction monitoring mode. The method had a short chromatographic run time of 2 minutes, and obtained sharp peaks of entecavir and the internal standard. Good linearity was found within 0.1 - 20 ng/mL. The intra- and inter-day precision and accuracy met the acceptance criteria, and no matrix effect was observed. This method was successfully applied in a bioequivalence study of two kinds of entecavir tablets in healthy Chinese volunteers. And the results showed that no significant differences were found between the test and reference preparations in pharmacokinetic parameters (p > 0.05) by ANOVA. The 90% confidence intervals for the geometric mean ratios (test/reference) of Cmax, AUC0-tlast, and AUC0-∞ fell within the bioequivalence acceptance criteria (80 - 125%). No significant difference was found in tmax between the two preparations. The two one-sided t-tests showed that these two products were bioequivalent.
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A Newly Designed Fiber-Optic Based Earth Pressure Transducer with Adjustable Measurement Range.

A novel fiber-optic based earth pressure sensor (FPS) with an adjustable measurement range and high sensitivity is developed to measure earth pressures for civil infrastructures. The new FPS combines a cantilever beam with fiber Bragg grating (FBG) sensors and a flexible membrane. Compared with a traditional pressure transducer with a dual diaphragm design, the proposed FPS has a larger measurement range and shows high accuracy. The working principles, parameter design, fabrication methods, and laboratory calibration tests are explained in this paper. A theoretical solution is derived to obtain the relationship between the applied pressure and strain of the FBG sensors. In addition, a finite element model is established to analyze the mechanical behavior of the membrane and the cantilever beam and thereby obtain optimal parameters. The cantilever beam is 40 mm long, 15 mm wide, and 1 mm thick. The whole FPS has a diameter of 100 mm and a thickness of 30 mm. The sensitivity of the FPS is 0.104 kPa/µÎµ. In addition, automatic temperature compensation can be achieved. The FPS's sensitivity, physical properties, and response to applied pressure are extensively examined through modeling and experiments. The results show that the proposed FPS has numerous potential applications in soil pressure measurement.

Pharmacokinetics and relative bioavailability of a generic amisulpride tablet in healthy Chinese volunteers
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OBJECTIVE: To assess and compare the pharmacokinetic properties and bioavailability of a newly developed formulation of amisulpride with those of a conventional formulation in healthy Chinese volunteers under fasting state. MATERIALS AND METHODS: A single-dose, two-sequence crossover study was designed. 20 healthy subjects (14 males and 6 females) were randomized into two groups. A single oral dose of amisulpride (200 mg) was given after an overnight fast of 12 hours. Blood samples were taken at scheduled time spots and separated by a washout period of 14 days. Plasma concentration of amisulpride was measured by high-performance liquid chromatography-fluorescence detector (HPLC-FLD) method. RESULTS: The pharmacokinetic parameters of AUC0-tlast, AUC0-∞, and Cmax for the 20 subjects after a single oral dose of the trial preparation or the reference preparation were 4,767.2 and 4,856.3 ng×h×mL-1; 4,891.7 and 5,043.2 ng×h×mL-1; 584.7 and 586.3 ng×mL-1, respectively. The relative bioavailability was 98.9 ± 14.5%. No significant difference was found among the main pharmacokinetic parameters in the two preparations by ANOVA. The 90% confidence intervals for the geometric mean ratios (test/reference) of Cmax and AUC0-tlast were 90.7 - 109.1% and 92.5 - 103.6%, respectively, meeting the predetermined criteria (80 - 125%) for bioequivalence. No serious adverse events were reported. CONCLUSION: The study demonstrated that the two preparations met the regulatory criteria for bioequivalence and both formulations were well tolerated.
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