A machine learning based method for tracking of simultaneously imaged neural activity and body posture of freely moving maggot.

To understand neural basis of animal behavior, it is necessary to monitor neural activity and behavior in freely moving animal before building relationship between them. Here we use light sheet fluorescence microscope (LSFM) combined with microfluidic chip to simultaneously capture neural activity and body movement in small freely behaving Drosophila larva. We develop a transfer learning based method to simultaneously track the continuously changing body posture and activity of neurons that move together using a sub-region tracking network with a precise landmark estimation network for the inference of target landmark trajectory. Based on the tracking of each labelled neuron, the activity of the neuron indicated by fluorescent intensity is calculated. For each video, annotation of only 20 frames in a video is sufficient to yield human-level accuracy for all other frames. The validity of this method is further confirmed by reproducing the activity pattern of PMSIs (period-positive median segmental interneurons) and larval movement as previously reported. Using this method, we disclosed the correlation between larval movement and left-right asymmetry in activity of a group of unidentified neurons labelled by R52H01-Gal4 and further confirmed the roles of these neurons in bilateral balance of body contraction during larval crawling by genetic inhibition of these neurons. Our method provides a new tool for accurate extraction of neural activities and movement of freely behaving small-size transparent animals.

Interpreting the chemical changes and therapeutic effect of Coptidis Rhizoma against ulcerative colitis before and after processing based on mathematical statistics and network pharmacology.

INTRODUCTION: Coptidis Rhizoma (CR) is one of the most frequently used herbs to treat ulcerative colitis (UC) and is often processed before usage. However, the composition changes and therapeutic effects of CR before and after processing in the treatment of UC are still unclear. OBJECTIVE: The purpose of the study is to explore the chemical components and therapeutic effects of crude and processed CR. MATERIAL AND METHODS: CR was processed according to the 2020 version of the Chinese Pharmacopoeia. The liquid chromatography-mass spectrometry (LC-MS) and multivariate statistical analysis were used to screen the different compounds before and after processing. The network pharmacological prediction was carried out. The mechanism and therapeutic effects between crude and processed CR were verified by using dextran sulphate sodium-induced UC mice assay. RESULTS: Ten compounds distinguish crude and processed CR based on multivariate statistical analysis. Network pharmacology predicts that the 10 compounds mainly play a role through TNF-α and IL-6 targets and PI3K/Akt and HIF-1 signalling pathways, and these results are verified by molecular biology experiments. For IL-6, IL-10 and TNF-α inflammatory factors, CR is not effective, while CR stir-fried with Evodiae Fructus (CRFE) and ginger juice (CRGJ) are. For PI3K/p-Akt, Cleaved caspase3, NF- κBp65 and HIF-1α signalling pathways, CR has therapeutic effects, while CRFE and CRGJ are significant. CONCLUSION: Overall, CRFE and CRGJ show better effects in treating UC. The chemical changes of processing and the efficacy of processed CR are correlated, which provides a scientific basis for the clinical use of crude and processed CR.

Tricolor narrowband planar perovskite photodetectors based on FP microcavity structure.

This paper presents a novel tunable narrowband photodetector based on Ag-MgF2-Ag (metal-dielectric-metal: MDM) Fabry-Perot (FP) microcavity structure. The tunability is achieved through precise adjustment of the thickness of the metal and intermediate dielectric layers of the FP microcavity, taking into account the response spectral range of planar perovskite. After optimizing the parameters mentioned above, the prototype devices were prepared by combining the perovskite layer and MDM layer. The center wavelength of the planar detector can be tuned from 430 nm to 680 nm within the detection band of 400-800 nm, with a narrow FWHM about 30 nm and a relatively high response of 0.05 A/W @ 5 V bias voltage for 500 nm. Meanwhile the rise and fall times of the detector are 375 ms and 550 ms, respectively. The experimental results are corroborated by the theory. Our design is highly beneficial to such applications as hyperspectral photography and color-related active optical devices, which paves the way to design this kind of triple structure.

N-Rich and Sulfur-Doped Nano Hollow Carbons with High Oxidase-like Activity Prepared Using a Green Template of CaCO3 for Bacteriostasis.

Nanozymes, enzyme-mimicking nanomaterials, have attracted increasing attention due to their low cost, high stability, and catalytic ability compared with natural enzymes. However, the catalytic efficiency of the nanozymes is still relatively low, and catalytic reaction mechanisms remain unclear. To address these issues, herein we prepared nitrogen-riched and sulfur-codoped nano hollow carbons (N/S-HCS) using a green and useful template of CaCO3. N/S-HCS exhibits enhanced oxidase-like activity and catalytic kinetic performance. It could directly oxidize the colorless 3,3',5,5'-tetramethylbenzidine (TMB) to the heavy blue colored ox-TMB without H2O2. The maximum reaction rate (Vmax) is 186.7 × 10-8 M·s-1, and Michaelis-Menten constant (Km) is 0.162 mM. DFT results show that N and S codoping could work synergistically to provide more active sites, resulting in the superior ability to adsorb oxygen and enhanced catalytic activity. Meantime, we develop a multispectral characterization strategy to unravel catalytic reaction mechanisms about N/S-HCS. It successfully induces the generation of superoxide (•O2-) and hydroxyl (•OH) during the colorimetric reaction which are the key intermediate products of the catalytic reaction. Furthermore, N/S-HCS increased the cellular reactive oxygen species level significantly and induced bacteriostasis to more than 95% of Escherichia coli.

Nitrogen addition stimulated soil respiration more so than carbon addition in alpine meadows.

The soil carbon (C) and nitrogen (N) availability are important in the regulation of soil C cycling under climate change. Fertilizers alter soil C and N availability, which can affect C balance. However, the impact of fertilizers on C balance in grassland restoration has been equivocal and warrants more research. We determined the direct and indirect effects of the addition of three levels of C (sucrose) (0, 60, and 120 kg C ha-1 yr-1), three levels of N (urea) (0, 50, and 100 kg N ha-1 yr-1), and a combination of C plus N at each of the levels on soil respiration (Rs) dynamics and C balance in an alpine meadow in northern Tibet (4700 m above sea level). This study was undertaken during the middle of the growing season in 2011-2012. The addition of C and/or N stimulated CO2 emission, which was 2-fold greater in 2011 (102-144 g C m-2) than in 2012 (43-54 g C m-2). The rate of Rs increased with the addition of N, but was not affected with the addition of C plus N. Microbial biomass C, dissolved organic C and inorganic N were the main drivers of Rs. We concluded that N addition stimulated Rs to a greater extent than C addition in the short term. The application of fertilizer in the restoration of degraded grassland should be re-considered.

Comparison of the effects of ampulla-guided realignment and conventional gallbladder triangle anatomy in difficult laparoscopic cholecystectomy.

OBJECTIVE: To compare the effects of ampulla-guided realignment and conventional gallbladder triangle anatomy in difficult laparoscopic cholecystectomy (DLC). METHODS: From June 2021 to August 2022, data from 100 patients undergoing DLC at Nanjing Hospital of Traditional Chinese Medicine were analyzed retrospectively. Patients were divided into two groups: the experimental group (LC with the ampulla-guided realignment) and the control group (conventional LC with triangular gallbladder anatomy), with 50 patients per group. The intraoperative blood loss, operation time, postoperative drainage tube indwelling time, hospitalization time, bile duct injury rate, operation conversion rate, and incidence of postoperative complications were recorded and compared between the two groups. The pain response and daily activities of the patients in the two groups were evaluated 48 h after the operation. RESULTS: The amount of intraoperative blood loss, postoperative drainage tube indwelling time, hospital stay, operation conversion rate, pain degree at 24 and 48 h after operation, bile duct injury incidence, and total postoperative complication rate were shorter or lower in the experimental group than those in the control group (p < 0.05). The Barthel index scores of both groups were higher 48 h after the operation than before the operation, and the experimental group was higher than the control group (p < 0.05). CONCLUSION: The ampulla-guided alignment in DLC surgery was more beneficial in promoting postoperative recovery, reducing postoperative pain response, reducing the incidence of postoperative complications, and reducing bile duct injury.

Integrated pathway and network analyses of metabolomic alterations in peripheral blood of patients with depression.

Depression is a serious mental illness, but the molecular mechanisms of depression remain unclear. Previous research has reported metabolomic changes in the blood of patients with depression, while integrated analysis based on these altered metabolites was still lacking. The objective of this study was to integrate metabolomic changes to reveal the underlying molecular alternations of depression. We retrieved altered metabolites in the blood of patients with depression from the MENDA database. Pathway analysis was conducted to explore enriched pathways based on candidate metabolites. Pathway crosstalk analysis was performed to explore potential correlations of these enriched pathways, based on their shared candidate metabolites. Moreover, potential interactions of candidate metabolites with other biomolecules such as proteins were assessed by network analysis. A total of 854 differential metabolite entries were retrieved in peripheral blood of patients with depression, including 555 unique candidate metabolites. Pathway analysis identified 215 significantly enriched pathways, then pathway crosstalk analysis revealed that these pathways were clustered into four modules, including amino acid metabolism, nucleotide metabolism, energy metabolism and others. Additionally, eight molecular networks were identified in the molecular network analysis. The main functions of these networks involved amino acid metabolism, molecular transport, inflammatory responses and others. Based on integrated analysis, our study revealed pathway-based modules and molecular networks associated with depression. These results will contribute to the underlying knowledge of the molecular mechanisms in depression.

MicroRNA-378 inhibits hepatocyte apoptosis during acute liver failure by targeting caspase-9 in mice.

BACKGROUND: Acute liver failure (ALF) is a severe and potentially lethal clinical syndrome. It has been demonstrated that micro ribonucleic acids (miRNAs) are crucial mediators of nearly all pathological processes, including liver disease. OBJECTIVE: The present study investigates the role of miR-378 in ALF. An ALF mouse model was induced using intraperitoneal injections of d-galactosamine/lipopolysaccharide (d-GalN/LPS). A hepatocyte cell line and miR-378 analogue were used in vitro to investigate the possible roles of miR-378 in ALF. METHODS: The expressions of miR-378 and predicted target genes were measured via reverse transcription-quantitative polymerase chain reaction and western blotting, and cell apoptosis was assayed using flow cytometry. RESULTS: Compared with mice in the control group, the mice challenged with d-GalN/LPS showed higher levels of alanine aminotransferase, aspartate aminotransferase, tumour necrosis factor-alpha and interleukin-6, more severe liver damage and increased numbers of apoptotic hepatocytes. Hepatic miR-378 was distinctly downregulated, while messenger RNA and protein levels of cysteinyl aspartate specific proteinase 9 (caspase-9) were upregulated in the ALF model. Furthermore, miR-378 was downregulated in d-GalN/TNF-induced hepatocyte cells, and miR-378 was found to inhibit hepatocyte apoptosis by targeting caspase-9. CONCLUSION: Together, the present results indicate that miR-378 is a previously unrecognised post-ALF hepatocyte apoptosis regulator and may be a potential therapeutic target in the context of ALF.

YAP1 activation promotes epithelial-mesenchymal transition and cell survival of renal cell carcinoma cells under shear stress.

Renal cell carcinoma (RCC) is characterized by substantial vasculatures and increased fluid movement in tumor microenvironment, and the fluid shear stress modulates malignance, extravasation and metastatic seeding of tumor cells. However, the precise mechanism remains largely unclear. In this study, we found that low shear stress induced the Yes-associated protein (YAP1) activation and nuclear localization in RCC cells, as well as the downregulation of phosphorylated YAP1 at Ser127. Moreover, inhibition of ROCK or RhoA partially abolished YAP1 accumulation in the nucleus, and targeting YAP1 activation by small molecular inhibitor or genetic manipulation decreased the low shear stress-induced epithelial-mesenchymal transition (EMT) of RCC cells, and led to a decreased expression of N-cadherin as accompanied by downregulation of SNAIL1 and TWIST, accompanied by high shear stress-induced cell apoptosis. Salvianolic acid B, an aqueous component of danshen (Salvia miltiorrhiza), inhibited YAP1 and Hippo signaling activation, and abrogated low shear stress-induced EMT as a consequence. Taken together, our study suggests YAP1 is a fluid mechanosensor that transforms mechanical stimuli to cell signals, thereby facilitates anoikis resistance and tumor metastasis.

Metabolomic changes in animal models of depression: a systematic analysis.

Extensive research has been carried out on the metabolomic changes in animal models of depression; however, there is no general agreement about which metabolites exhibit constant changes. Therefore, the aim of this study was to identify consistently altered metabolites in large-scale metabolomics studies of depression models. We performed vote counting analyses to identify consistently upregulated or downregulated metabolites in the brain, blood, and urine of animal models of depression based on 3743 differential metabolites from 241 animal metabolomics studies. We found that serotonin, dopamine, gamma-aminobutyric acid, norepinephrine, N-acetyl-L-aspartic acid, anandamide, and tryptophan were downregulated in the brain, while kynurenine, myo-inositol, hydroxykynurenine, and the kynurenine to tryptophan ratio were upregulated. Regarding blood metabolites, tryptophan, leucine, tyrosine, valine, trimethylamine N-oxide, proline, oleamide, pyruvic acid, and serotonin were downregulated, while N-acetyl glycoprotein, corticosterone, and glutamine were upregulated. Moreover, citric acid, oxoglutaric acid, proline, tryptophan, creatine, betaine, L-dopa, palmitic acid, and pimelic acid were downregulated, and hippuric acid was upregulated in urine. We also identified consistently altered metabolites in the hippocampus, prefrontal cortex, serum, and plasma. These findings suggested that metabolomic changes in depression models are characterized by decreased neurotransmitter and increased kynurenine metabolite levels in the brain, decreased amino acid and increased corticosterone levels in blood, and imbalanced energy metabolism and microbial metabolites in urine. This study contributes to existing knowledge of metabolomic changes in depression and revealed that the reproducibility of candidate metabolites was inadequate in previous studies.

Study on the metabolism profile of flavanomarein in Coreopsis tinctoria Nutt.

Coreopsis tinctoria Nutt. (family Asteraceae) is a popular medicine-food plant, which improves chronic diseases such as hyperlipemia, hypertension, and diabetes. Flavanomarein is the main active component of Coreopsis tinctoria Nutt, in which the blood concentration of volunteers is low and bioavailability is poor. Thus, the understanding of flavanomarein metabolites and metabolic pathways is significant to clarify its effectiveness. This study systematically studied the metabolites of flavanomarein by oral and injection. The biological samples (feces, urine, and plasma) were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry in negative ion mode. The metabolic law of flavanomarein in the liver was further verified by a liver microsomal incubation experiment in vitro. A total of 12 metabolites were identified by oral administration while 15 metabolites were detected by injection. It was shown that metabolic pathways include acetylation, hydroxylation, glucuronidation, methylation, dehydrogenation, and so forth. The liver extraction rate of flavanomarein was 0.08, which means the metabolic stability of flavanomarein is well in rats' liver microsomes. It is a systematic study on the metabolism of flavanomarein and provides a metabolic rationale for further in-depth in vivo biotransformation.

Experimental Determination and Computational Prediction of Dehydroabietic Acid Solubility in (-)-α-Pinene + (-)-ß-Caryophyllene + P-Cymene System.

The solubility of dehydroabietic acid in (-)-α-pinene, p-cymene, (-)-ß-caryophyllene, (-)-α-pinene + p-cymene, (-)-ß-caryophyllene + p-cymene and (-)-α-pinene + (-)-ß-caryophyllene were determined using the laser monitoring method at atmospheric pressure. The solubility of dehydroabietic acid was positively correlated with temperature from 295.15 to 339.46 K. (-)-α-pinene, p-cymene, and (-)-ß-caryophyllene were found to be suitable for the solubilization of dehydroabietic acid. In addition, the non-random two liquid (NRTL), universal quasi-chemical (UNIQUAC), modified Apelblat, modified Wilson, modified Wilson-van't Hoff, and λh models were applied to correlate the determined solubility data. The modified Apelblat model gave the minor deviation for dehydroabietic acid in monosolvents, while the λh equation showed the best result in the binary solvents. A comparative analysis of compatibility between solutes and solvents was carried out using Hansen solubility parameters. The thermodynamic functions of ΔsolH0, ΔsolS0, ΔsolG0 were calculated according to the van't Hoff equation, indicating that the dissolution was an entropy-driven heat absorption process. The Conductor-like Screening Model for Real Solvents (COSMO-RS) combined with an experimental value was applied to predict the reasonable solubility data of dehydroabietic acid in the selected solvents systems. The interaction energy of the dehydroabietic acid with the solvent was analyzed by COSMO-RS.

Investigation of a Complex Reaction Pathway Network of Isobutane/2-Butene Alkylation by CGC-FID and CGC-MS-DS.

The mechanism of reaction in isobutane/2-butene alkylation systems is extremely complicated, accompanied by numerous side reactions. Therefore, a comprehensive understanding of the reaction pathways in this system is essential for an in-depth discussion of the reaction mechanism and for improving the selectivity of the major products (clean fuel blend components). The alkylation of isobutane/2-butene was studied using a self-made intermittent reaction device with a metering, cooling, reaction, vacuum and analysis system. The alkylates were qualitatively and quantitatively analyzed using a capillary gas chromatography-mass spectrometry-data system (CGC-MS-DS) and capillary gas chromatography with flame ionization detection (CCGC-FID), respectively, and the precision and recovery of the quantitative analytical methods were verified. The results showed that the relative standard deviation (RSD) of the standard sample was below 0.78%, and the recoveries were from 98.53% to 102.85%. Under the specified reaction conditions, 79 volatile substances were identified from the alkylates, and the selectivity of C8 and trimethylpentanes (TMPs) reached 63.63% and 53.81%, respectively. The changes of the main chemical components in the alkylation reaction with time were tracked and analyzed, based on which reaction pathways were determined, and a complex reaction network containing the main products' and the by-products' generation pathway was constructed.

Pharmacokinetic study of Tangwang Mingmu granule for the management of diabetic retinopathy based on network pharmacology.

CONTEXT: Tangwang Mingmu granule (TWMM), a traditional Chinese medicine, has been widely used in the treatment of diabetic retinopathy (DR), the most common microvascular complication in diabetes mellitus. OBJECTIVE: To establish a method to select target compounds from herbs for a pharmacokinetic study using network pharmacology, which could be applied in clinical settings. MATERIALS AND METHODS: First, UPLC/Q Exactive Q-Orbitrap and GCMS 2010 were used to determine the non-volatile and volatile ingredients of TWMM. Based on the identified compounds, network pharmacology was used to screen the key compounds and targets of TWMM in the treatment of DR. Based on the compound-target-pathway network and identification of components emigrant into blood, the potential compound markers in vivo were chosen. Then, Sprague-Dawley (SD) rats were administrated of TWMM at a 9.6 g/kg dose to investigating pharmacokinetic parameters using the UPLC-QQQ-MS. RESULTS: Ninety and forty-five compounds were identified by UPLC-MS and GC-MS, respectively. Based on the network pharmacology, nine compounds with a degree value above 15 were screened and implied that these compounds are the most active in DR treatment. Moreover, criteria of degree value greater than 7 were applied, and PTGS2, NOS2, AKT1, ESR1, TNF, and MAPK14 were inferred as the core targets in treating DR. After identification of components absorbed into blood, luteolin and formononetin were selected and used to investigate the pharmacokinetic parameters of TWMM after its oral administration. CONCLUSIONS: The reported strategy provides a method that combines ingredient profiling, network pharmacology, and pharmacokinetics to determine luteolin and formononetin as the pharmacokinetic markers of TWMM. This strategy provides a clinically relevant methodology that allows for the screening of pharmacokinetic markers in Chinese medicines.

[Predictive analysis of quality markers of Coptidis Rhizoma based on network pharmacology and multivariate statistical analysis].

Coptidis Rhizoma, as a bulk medicinal material, is in great demand in clinical practice. Its quality is uneven in the market due to the mixture of genuine, counterfeit and adulterants. Therefore, it is particularly important to establish a quality control system for Coptidis Rhizoma. Based on the concept of Chinese medicine quality marker(Q-marker), the potential quality markers of Coptidis Rhizoma were analyzed and predicted from the perspective of chemistry and pharmacology. The sources of the Q-markers of Coptidis Rhizoma were identified by literature retrieval. The potential Q-markers were then screened through the visualization of the "components-targets-pathways" network. High performance liquid chromatography(HPLC) was used to establish a multi-indicator qualitative and quantitative control method featuring fingerprints for 10 batches of Coptidis Rhizoma. A supervised mode of orthogonality partial least squares method-discriminant analysis(OPLS-DA) was used to screen the main marker components that caused differences between groups. The literature review results showed that the alkaloids were the main source of Coptidis Rhizoma Q-markers.The fingerprints of 13 common peaks were successfully established, and berberine, palmatine, berberine and epiberberine were selected as Q-markers of Coptidis Rhizoma, and their contents were determined.Based on the concept of the Q-marker of traditional Chinese medicine, the four components can be selected as the Q-marker of Coptidis Rhizoma after comprehensive consideration. The results of this study are not only conducive to the quality evaluation of Coptidis Rhizoma on the market, but also provide a reference for the overall quality control of Coptidis Rhizoma and lay foundation for the future exploration of the mechanism of Coptidis Rhizoma.

Identification of prototypes from Ligustri Lucidi Fructus in rat plasma based on a data-dependent acquisition and multicomponent pharmacokinetic study.

The identification and quantization of traditional Chinese medicine (TCM) are a challenge for researchers and industry. Using untargeted analytical methods, the in vivo detection and identification of TCM compounds are difficult because of the significant interference of endogenous substances. Fortunately, the ongoing development of new analytical technologies, especially Q-Orbitrap-MS, offers some solutions. Our team developed a holistic MS method, combining untargeted data-dependent MS2 (dd-MS2 ) modes to extensively identify TCM prototypes in vivo. The method was successfully applied to the analysis of Ligustri Lucidi Fructus (LLF). LLF is a widely used TCM with a remarkable nourishing effect on the liver and kidney. In the study, we aimed to identify the prototypes in rat plasma after oral administration of LLF extract. Following separation on an HSS T3 column, LLF extract and rat plasma were performed in untargeted dd-MS2 mode. Forty-seven compounds were characterized in rats plasma as prototypes of LLF extract. Furthermore, seven major prototypes were chosen as pharmacokinetic markers to investigate LLF's pharmacokinetic properties. The results provides comprehensive determination of compounds in LLF both in vitro and in vivo, which is important for quality control, pharmacology studies and clinical use of LLF.

Eye Gaze Based 3D Triangulation for Robotic Bionic Eyes.

Three-dimensional (3D) triangulation based on active binocular vision has increasing amounts of applications in computer vision and robotics. An active binocular vision system with non-fixed cameras needs to calibrate the stereo extrinsic parameters online to perform 3D triangulation. However, the accuracy of stereo extrinsic parameters and disparity have a significant impact on 3D triangulation precision. We propose a novel eye gaze based 3D triangulation method that does not use stereo extrinsic parameters directly in order to reduce the impact. Instead, we drive both cameras to gaze at a 3D spatial point P at the optical center through visual servoing. Subsequently, we can obtain the 3D coordinates of P through the intersection of the two optical axes of both cameras. We have performed experiments to compare with previous disparity based work, named the integrated two-pose calibration (ITPC) method, using our robotic bionic eyes. The experiments show that our method achieves comparable results with ITPC.

The Emulsifying Properties of Hydrogenated Rosin Xylitol Ester as a Biomass Surfactant for Food: Effect of pH and Salts.

The xylitol ester of hydrogenated rosin (XEHR) was obtained for the first time from biomass-based hydrogenated rosin and xylitol using an environmentally friendly, high-pressure CO2 catalytic synthesis. This compound is intended for use as an emulsifier for food. Analyses by ICP-AES showed the absence of heavy metal residues in the product, such that it met food standards. Fourier transform infrared and nuclear magnetic resonance spectroscopies together with gel permeation chromatography confirmed the successful esterification and the formation of a monoester and diester with molar masses of 427 and 772 g/mol. The emulsification of water/soybean oil mixtures by adding the XEHR was assessed at pH values of 4, 6.86, and 10 and in the presence of NaCl, KCl, MgCl2, and CaCl2. The XEHR was found to act as an emulsifier by reducing the interfacial tension of such mixtures to less than 2 mN/m under all conditions. The highest emulsifying activity index (9.52 m2/g) and emulsifying stability index (94.53%) were obtained after adding MgCl2 (100 mM). Particle size and confocal microscopy showed that the presence of salts gave a more uniform droplet size and a finer emulsion structure. The high viscosities of the emulsions containing salts also suggested a more cohesive oil droplet network.

The influences of "gas" viscosity on water entry of hydrophobic spheres.

An extremely thin gas film was found between a sphere and a free surface when the sphere impacted onto a water pool. That might influence the generation and evolution of water entry cavity. However, it is quite difficult to be captured through normal numerical and experimental tests. In this work, by using a finite element method we investigate the water entry of a hydrophobic sphere with gas viscosity artificially increased. The air film rupture in the early stage, contact line dynamics on a curved solid surface, and air pocket formation are investigated. The numerical results reveal that the lifetime of the gas film can be predicted by a viscous squeezing flow model qualitatively well. That relates to the fact that the gas film is much thinner than the diameter of the sphere, even when the gas viscosity is 100 times as large as the liquid one. However, inviscid flow can be found in the most part of the liquid bulk. The free surface profile (or the gas film profile) is then determined by the impact speed, namely the Weber number. More importantly, after the "gas" film ruptures at the bottom of the sphere, a contact line is generated. The contact line retracts along the sphere's surface, and the retracting speed fulfils [Formula: see text] law generally. This implies that the retracting process of the gas film is dominated by the inertia-capillary balance, rather than simply by the visco-capillary.

Effects of thyroid hormone disruption on the ontogenetic expression of thyroid hormone signaling genes in developing zebrafish (Danio rerio).

Thyroid hormones (THs) regulate neurodevelopment, thus TH disruption is widely posited as a mechanism of developmental neurotoxicity for diverse environmental chemicals. Zebrafish have been proposed as an alternative model for studying the role of TH in developmental neurotoxicity. To realize this goal, it is critical to characterize the normal ontogenetic expression profile of TH signaling molecules in the developing zebrafish and determine the sensitivity of these molecules to perturbations in TH levels. To address these gaps in the existing database, we characterized the transcriptional profiles of TH transporters, deiodinases (DIOs), receptors (TRs), nuclear coactivators (NCOAs), nuclear corepressors (NCORs), and retinoid X receptors (RXRs) in parallel with measurements of endogenous TH concentrations and tshß mRNA expression throughout the first five days of zebrafish development. Transcripts encoding these TH signaling components were identified and observed to be upregulated around 48-72 h post fertilization (hpf) concurrent with the onset of larval production of T4. Exposure to exogenous T4 and T3 upregulated mct8, dio3-b, trα-a, trß, and mbp-a levels, and downregulated expression of oatp1c1. Morpholino knockdown of TH transporter mct8 and treatment with 6-propyl-2-thiouracil (PTU) was used to reduce cellular uptake and production of TH, an effect that was associated with downregulation of dio3-b at 120 hpf. Collectively, these data confirm that larval zebrafish express orthologs of TH signaling molecules important in mammalian development and suggest that there may be species differences with respect to impacts of TH disruption on gene transcription.