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A validated hydrodynamic-biogeochemical model was applied to investigate the effects of physical forcing (i.e., river discharge, winds, and tides) on the summertime dissolved oxygen (DO) dynamics and hypoxia (DO < 3 mg L−1) in the Pearl River estuary (PRE), based on a suite of model sensitivity experiments. Compared with the base model run in 2006 (a wet year), the simulated hypoxic area in the moderate year (with 75% of river discharge of the base run) and the dry year scenario (with 50% of river discharge of the base run) was reduced by ~30% and ~60%, respectively. This is because under the lower river discharge levels, less particulate organic matter was delivered to the estuary that subsequently alleviated the oxygen demand at the water–sediment interface, and in the meantime, the water stratification strength was decreased, which facilitated the vertical diffusion of DO. Regarding the effect of winds, the highly varying and intermittent strong winds had a significant impact on the replenishment of bottom DO by disrupting water stratification and thus inhibiting the development of hypoxia. Sensitivity experiments showed that the hypoxic area and volume were both remarkably increased in the low wind scenario (with a bottom hypoxic zone extending from the Modaomen sub-estuary to the western shoal in Lingdingyang Bay), whereas hypoxia was almost absent in the strong wind scenario. The DO budget indicated that winds altered the bottom DO mostly by affecting the DO flux due to vertical diffusion and horizontal advection, and had a limited influence on the DO consumption processes. Moreover, the DO concentration exhibited remarkable fluctuations over the spring-neap tidal cycles due to the significant differences in vertical diffusion. The results of a tide-sensitivity experiment indicated that without tide forcing, most of the shallow areas (average water depth < 5 m) in the PRE experienced severe and persistent hypoxia. The tides mainly enhanced mixing in the shallow areas, which led to higher vertical diffusion and enhanced replenishment of bottom DO. [ABSTRACT FROM AUTHOR]

Random sensor arrays are examined from a compressive-sensing (CS) perspective, particularly in terms of the coherence of compressive-sensing matrices. It is demonstrated that the maximum sidelobe level of an array corresponds to the coherence of interest for compressive sensing. This understanding is employed to explicitly quantify the accuracy of array source localization as a function of the number of sources and the noise level. The analysis demonstrates that the compressive-sensing theory is applicable to arrays in vacuum, as well as in the presence of a surrounding linear medium. Furthermore, the presence of a surrounding media with known properties may be used to improve array performance, with this related to phase conjugation and time reversal. Several numerical results are presented to demonstrate the theory. [ABSTRACT FROM PUBLISHER]

Objectives: Vertigo is a prevalent clinical symptom, frequently associated with benign paroxysmal positional vertigo (BPPV), Ménière disease (MD), and vestibular neuritis (VN), which are three common peripheral vestibular disorders. However, there is a relative lack of research in epidemiology and etiology, with some existing studies presenting discrepancies in their conclusions. We conducted a two-sample Mendelian randomization (MR) analysis to explore potential risk and protective factors for these three peripheral vestibular disorders., Design: Based on genome-wide association studies, we executed a univariable MR to investigate the potential associations between 38 phenotypes and MD, BPPV, and VN. We used the inverse variance weighted method as the primary MR result and conducted multiple sensitivity analyses. We used false discovery rate (FDR) correction to control for type I errors. For findings that were significant in the univariable MR, a multivariable MR analysis was implemented to ascertain direct effects. In addition, we replicated analyses of significant results from the univariable MR to enhance the robustness of our analyses., Results: For BPPV, both alcohol consumption (odds ratio [OR] = 0.57, 95% confidence interval [CI] = 0.43 to 0.76, FDR Q = 0.004) and educational attainment (OR = 0.77, 95% CI = 0.68 to 0.88, FDR Q = 0.003) were found to decrease the risk. The genetic prediction analysis identified major depression (OR = 1.75, 95% CI = 1.28 to 2.39, FDR Q = 0.008) and anxiety (OR = 5.25, 95% CI = 1.79 to 15.42, FDR Q = 0.036) increased the risk of MD. However, the impact of major depression on MD could be influenced by potential horizontal pleiotropy. Systolic blood pressures (OR = 1.03, 95% CI = 1.02 to 1.04, FDR Q = 4.00 × 10 -7 ) and diastolic blood pressures (OR = 1.05, 95% CI = 1.03 to 1.07, FDR Q = 2.83 × 10 -6 ) were associated with an increased risk of VN, whereas high-density lipoprotein (OR = 0.77, 95% CI = 0.67 to 0.89, FDR Q = 0.009) and urate (OR = 0.75, 95% CI = 0.63 to 0.91, FDR Q = 0.041) reduces the risk of VN. Only the relationship between urate and VN was not replicated in the replication analysis. Multivariable MR showed that the protective effect of education on BPPV was independent of Townsend deprivation index. The protective effect of high-density lipoprotein against VN was independent of triglycerides and apolipoprotein A1. The risk impacts of systolic and diastolic blood pressures on VN exhibited collinearity, but both are independent of chronic kidney disease and estimated glomerular filtration rate. The impacts of anxiety and severe depression on MD demonstrated collinearity., Conclusions: Our study identified the risk association between systolic and diastolic blood pressure with VN and the protective influence of high-density lipoprotein on VN, which may support the vascular hypothesis underlying VN. Furthermore, we observed an elevated risk of MD associated with anxiety. The potential protective effects of education and alcohol consumption on BPPV need further exploration in subsequent studies to elucidate specific mechanistic pathways. In summary, our MR study offers novel insights into the etiology of three peripheral vestibular diseases from a genetic epidemiological standpoint., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

In the present study, we aimed to explore the effect of environmental endocrine disruptors (EEDs) on sexual differentiation in androgen receptor (AR)-/-, AR+/- and AR+/+ male mice. By using a Cre-loxP conditional knockout strategy, we generated AR knockout mice. By mating flox-AR female mice with AR-Cre male mice, the offspring male mice which were produced were examined. Mice not subjected to any type of intervention were used as the controls. Furthermore, male mice of different genotypes were selected and further divided into subgroups as follows: the control group, bisphenol A (BPA) group and the dibutyl phthalate [corrected] (DBP) group. The expression of the Wilms tumor 1 (WT1), lutropin/choriogonadotropin receptor (LHR), 17-β-hydroxysteroid dehydrogenase type 3 (17βHSD3) and steroid-5-alpha-reductase, alpha polypeptide 2 (SRD5A2) genes was determined by RT-qPCR and western blot analysis. There was no statistically significant difference in the weight of the mice between the control group and the knockout group (P>0.05). The results revealed that, compared with the control group, in the knockout group, anogenital distance was shortened, and testicular weight and testosterone levels were decreased; estradiol levels were elevated; the differences were statistically significant (P<0.05). In the group of AR+/- male mice exposed to 100 mg/l EEDs, hypospadias was successfully induced, suggesting that EEDs are involved in the embryonic stage of sexual development in male mice. The quantitative detection of WT1, LHR, 17βHSD3 and SRD5A2 gene expression by RT-qPCR and western blot analysis indicated that these genes were significantly downregulated in the mice in the BPA group. In conclusion, exposure to EEDs induces hypospadias in heterozygous and wild-type male mice offspring during sexual differentiation, but has no effect on homozygous offspring. Therefore, EEDs play an important role during the third stage of sexual differentiation.

Objective: To investigate the dynamic effects of adjunct peritoneal resuscitation ( APR ) on the early intestinal injury of rats with hemorrhagic shock, and explore its possible mechanisms., Methods: According to random number table, 96 male Wistar rats were assigned randomly into control group, shock group, Ringer solution APR group and dialysate APR group. Each group was further divided into three time points, namely 1, 2, and 6 hours after resuscitation, with 8 rats for each time point. The model of hemorrhagic shock was reproduced. The rats in the shock group received shed blood plus twice amount of normal saline as conventional intravenous resuscitation ( CIR ). Besides CIR, at the beginning of resuscitation, those rats in Ringer solution APR and dialysate APR groups were given 100 mL/kg of Ringer solution or 2.5% glucose-based peritoneal dialysis solution intravenously, respectively. The rats in four groups were sacrificed at 1, 2 and 6 hours after resuscitation, respectively. Plasma activity of diamine oxidase ( DAO ) was detected by ultraviolet spectrophotometry colorimetry. Intestinal pathological changes were observed under light microscope, and the grading of the intestinal mucosal damage ( GIMD ) score was estimated. The expressions of nuclear factor-ΚB ( NF-ΚB ) and heat shock protein 70 ( HSP70 ) mRNA in the intestinal tissue were determined with reverse transcription-polymerase chain reaction ( RT-PCR ), and the wet/dry weight ratios ( W/D ) of the remaining intestinal tissue were measured., Results: Compared with the control group, plasma activity of DAO, GIMD score, expressions of NF-ΚB and HSP70 mRNA and W/D ratios of intestinal tissue at 1 hour after resuscitation were increased significantly in the shock group. Except the expression of NF-ΚB mRNA reached the peak level at 2 hours after resuscitation, all the other parameters increased with time. Compared with the shock group, plasma activity of DAO ( U/L: 8.78±0.76 vs. 13.30±1.37, 9.67±0.92 vs. 16.56±1.61, 10.53±0.84 vs. 18.31±1.72,all P<0.05 ), GIMD score ( 1.36±0.31 vs. 3.51±0.66, 2.28±0.40 vs. 4.02±0.76, 2.47±0.38 vs. 4.76±0.77, all P<0.05 ), the expressions of NF-ΚB mRNA in the intestine tissue ( gray value: 0.658±0.062 vs. 0.765±0.067, 0.945±0.077 vs. 1.158±0.096, 0.761±0.062 vs. 0.912±0.082, all P<0.05 ), and W/D ratios ( 3.91±0.26 vs. 4.34±0.33, 3.96±0.32 vs. 4.51±0.40, 4.37±0.33 vs. 4.99±0.43, all P<0.05 ) at 1, 2, 6 hours after resuscitation in the dialysate APR group were decreased significantly, but the expressions of HSP70 mRNA were increased significantly ( gray value: 0.717±0.054 vs. 0.635±0.056, 0.853±0.068 vs. 0.745±0.071, 1.258±0.111 vs. 1.108±0.105, all P<0.05 ). The activity of DAO and GMID score at 1 hour after resuscitation in the Ringer solution APR group were decreased significantly compared with the shock group, while the differences of the other parameters between the Ringer solution APR group and shock group showed no statistical significance., Conclusions: APR with 2.5% glucose-based peritoneal dialysis solution can significantly mitigate the early intestinal injury secondary to hemorrhagic shock, and the mechanism may be associated with enhancement of the expressions of HSP70 mRNA and inhibition of the expressions of NF-ΚB mRNA.