Influence of scale effect on flow field offset for ships in confined waters

To investigate the flow field characteristics of full-scale ships advancing through confined waters, the international standard container ship (KRISO Container Ship) was considered as a research object in this study. Using the RANS equation, the volume of fluid method and the body force method were selected to investigate the hydrodynamic characteristics of a model-scale ship (the model-scale ratio λ=31.6) and a full-scale ship advancing through confined waters at low speed. A virtual disk was used in the full-scale model to determine the influence of the propeller on the ship’s flow field. First, the feasibility of the numerical calculations was verified. This proves the feasibility of the numerical and grid division methods. The self-propulsion point of the full-scale ship at Fr=0.108 is determined. The calculation cases of model-scale and full-scale ships (with or without virtual disks) at different water depths and distances between the ship and the shore were calculated, and the changes in the hull surface pressure, the flow field around the ship, and the wake fraction near the ship propeller disk in different calculation cases were determined and compared. The variations in the surge force, sway force, and yaw moment between the model- scale and full-scale ships were generally consistent. In very shallow water (H/T=1.3), the non-dimensional force and moment coefficients for model-scale ships increase more rapidly with decreasing distance from shore, suggesting that using model-scale ships to investigate the wall effect in very shallow water will result in predictions that are biased towards safety. By comparing full-scale ships with and without propellers, it was discovered that the surge force, sway force, and yaw moment were marginally greater in the propeller-equipped ship due to the suction effect, and the accompanying flow before and after the propeller was slightly smaller, with less asymmetry

Improving Mechanical Properties of Magnesium Phosphate Cement-Based Ultra-High Performance Concrete by Ultrafine Fly Ash Incorporation

Magnesium phosphate cement-based ultra-high-performance concrete (MPC-UHPC) develops strength rapidly but shows unsatisfactory ultimate strength (\u3c150 \u3eMPa). In this study, ultrafine fly ash (UFA) was incorporated in MPC-UHPC to improve mechanical properties. The effect of UFA content, varying from 0 % to 15 %, by weight of binder, on microstructure, fiber pullout behavior, mechanical strengths, flexural and tensile properties of MPC-UHPC reinforced with 2 vol% steel fibers was investigated. Experimental results indicate that the incorporation of 10 %–15 % UFA with mean particle size of 1.4 µm was effective in reducing porosity and microcracks of binder matrix and fiber–matrix interface, thereby resulting in significantly improved fiber–matrix bond properties. The 28-d average bond strength and pullout energy could increase by 27 % and 57 % at 15 % UFA addition, respectively. Such UFA addition level was found to yield a mix with 158.3 MPa compressive strength and substantially enhance the flexural and tensile fracture properties. The result reported herein will further promote the utilization of UFA for the development of MPC materials with outstanding mechanical properties

Modeling RedOx-Based Magnetohydrodynamics in Three-Dimensional Microfluidic Channels

RedOx-based magnetohydrodynamic MHD[1] flows in three-dimensional microfluidic channels are investigated theoretically with a coupled mathematical model consisting of the Nernst-Planck equations for the concentrations of ionic species, the local electroneutrality condition for the electric potential, and the Navier-Stokes equations for the flow field. A potential difference is externally applied across two planar electrodes positioned along the opposing walls of a microchannel that is filled with a dilute RedOx electrolyte solution, and a Faradaic current transmitted through the solution results. The entire device is positioned under a magnetic field which can be provided by either a permanent magnet or an electromagnet. The interaction between the current density and the magnetic field induces Lorentz forces, which can be used to pump and/or stir fluids for microfluidic applications. The induced currents and flow rates in three-dimensional 3D[1] planar channels obtained from the full 3D model are compared with the experimental data obtained from the literature and those obtained from our previous two-dimensional mathematical model.Aclosed form approximation for the average velocity flow rate[1] in 3D planar microchannels is derived and validated by comparing its predictions with the results obtained from the full 3D model and the experimental data obtained from the literature. The closed form approximation can be used to optimize the dimensions of the channel and to determine the magnitudes and polarities of the prescribed currents in MHD networks so as to achieve the desired flow patterns and flow rates

Identification of a novel SPTB gene splicing mutation in hereditary spherocytosis: a case report and diagnostic insights

BackgroundHereditary spherocytosis (HS) is a group of genetically heterogeneous hereditary hemolytic disorders characterized by anemia, splenomegaly, jaundice, reticulocytosis, and spherical red blood cells on peripheral blood smears. Mutations in key genes, including SPTB, ANK1, SLC4A1, SPTA1, and EPB42, are commonly implicated in HS.Case PresentationWe report the case of a 22-year-old female presenting with anemia, jaundice, and a family history of splenectomy. Laboratory investigations revealed hemolytic anemia, elevated bilirubin levels, and peripheral blood smear findings consistent with HS. Genetic testing identified a novel SPTB gene splicing mutation (NM_001355436.2: c.1645-1G>A), inherited maternally, which is predicted to disrupt normal RNA splicing and protein synthesis.DiscussionThe identified SPTB mutation expands the known mutation spectrum of the SPTB gene and highlights its role in the pathogenesis of HS. Clinical findings, combined with genetic analysis, confirmed the diagnosis of HS and underscored the importance of comprehensive molecular testing for accurate diagnosis, especially in patients with a strong family history.ConclusionThis case emphasizes the utility of genetic testing in diagnosing hereditary spherocytosis, particularly for novel gene mutations. Early and accurate molecular diagnosis facilitates better clinical management, family counseling, and treatment decisions for patients with HS

A Conditioned Medium of Umbilical Cord Mesenchymal Stem Cells Overexpressing Wnt7a Promotes Wound Repair and Regeneration of Hair Follicles in Mice

Mesenchymal stem cells (MSCs) can affect the microenvironment of a wound and thereby accelerate wound healing. Wnt proteins act as key mediators of skin development and participate in the formation of skin appendages such as hair. The mechanisms of action of MSCs and Wnt proteins on skin wounds are largely unknown. Here, we prepared a Wnt7a-containing conditioned medium (Wnt-CM) from the supernatant of cultured human umbilical cord-MSCs (UC-MSCs) overexpressing Wnt7a in order to examine the effects of this CM on cutaneous healing. Our results revealed that Wnt-CM can accelerate wound closure and induce regeneration of hair follicles. Meanwhile, Wnt-CM enhanced expression of extracellular matrix (ECM) components and cell migration of fibroblasts but inhibited the migratory ability and expression of K6 and K16 in keratinocytes by enhancing expression of c-Myc. However, we found that the CM of fibroblasts treated with Wnt-CM (HFWnt-CM-CM) can also promote wound repair and keratinocyte migration; but there was no increase in the number of hair follicles of regeneration. These data indicate that Wnt7a and UC-MSCs have synergistic effects: they can accelerate wound repair and induce hair regeneration via cellular communication in the wound microenvironment. Thus, this study opens up new avenues of research on the mechanisms underlying wound repair

MCICSAM: Monte Carlo-guided Interpolation Consistency Segment Anything Model for Semi-Supervised Prostate Zone Segmentation

Accurate segmentation of various regions within the prostate is pivotal for diagnosing and treating prostate-related diseases. However, the scarcity of labeled data, particularly in specialized medical fields like prostate imaging, poses a significant challenge. Segment Anything Model (SAM) is a new large model for natural image segmentation, but there are some challenges in medical imaging. In order to better utilize the powerful feature extraction capability of SAM as well as to address the problem of low data volume for medical image annotation, we use Low-Rank Adaptation (LoRA) and semi-supervised learning methods of Monte Carlo guided interpolation consistency (MCIC) to enhance the fine-tuned SAM. We propose Monte Carlo-guided Interpolation Consistency Segment Anything Model (MCICSAM) for application to semi-supervised learning based prostate region segmentation. In the unlabeled data section, MCIC performs two different interpolation transformations on the input data and incorporates Monte Carlo uncertainty analysis in the output, forcing the model to be consistent in its predictions. The consistency constraints imposed on these interpolated samples allow the model to fit the distribution of unlabeled data better, ultimately improving its performance in semi-supervised scenarios. We use Dice and Hausdorff Distance at 95th percentile (HD95) to validate model performance. MCICSAM yieldes Dice with 79.38% and 89.95%, along with improves HD95 values of 3.12 and 2.27 for transition zone and transition zone. At the same time MCICSAM demonstrates strong generalizability. This method is expected to bring new possibilities in the field of prostate image segmentation.13 pages, 5 figure

Assessing cognitive impairment in home-dwelling Chinese elders aged 80+: a detailed survey of 13,000 participants focusing on demographic factors, social engagement, and disease prevalence

IntroductionCognitive Impairment (CI) in the elderly, encompassing conditions ranging from Mild Cognitive Impairment (MCI) to dementia, represents a growing public health concern globally. This study aims to investigate the prevalence and correlates of CI among individuals aged 80 and above.MethodsThe study conducts 13,027 elderly individual’s door-to-door surveys, followed by the cross-tabulation of analysis data, logistic regression analysis, and health condition assessments to examine various determinants of CI.ResultsThe current study’s key findings demonstrate sub-statical correlations between CI and various factors, including educational attainment, marital status, and gender. Pronounced differences are evident between urban and rural demographics. Furthermore, aspects of social engagement, notably communication proficiency and sensory capabilities, exhibit a strong association with CI. Logistic regression analysis highlights that residing in rural areas (Odds Ratio [OR] = 0.637) and being female (OR = 0.71) are linked to a decreased risk of CI. In contrast, behavioral and health-related variables present a complex picture. Specifically, aggressive behavior (Adjusted OR = 1.881) and symptoms of depression (Adjusted OR = 0.549) contrast with conditions such as asthma (OR= 2.857) and cerebral infarction (OR=1.348), which elevate the risk of CI. Intriguingly, hyperlipidemia (OR= 0.671) appears to confer a protective effect against CI.ConclusionThe study highlights the complexity of factors affecting CI in the elderly, advocating for a comprehensive approach to understanding and managing cognitive health

A Modified Hyaluronic Acid–Based Dissolving Microneedle Loaded With Daphnetin Improved the Treatment of Psoriasis

Psoriasis is a common chronic immune-inflammatory disease. Challenges exist in the present treatment of psoriasis, such as difficulties in transdermal drug administration and severe side effects. We hope to achieve a better therapeutic outcome for psoriasis treatment. By using modified soluble microneedles (MNs) loaded with daphnetin, the psoriasis symptoms of mice, the abnormal proliferation of keratinocytes, and the secretion of inflammatory factors were significantly reduced. In vitro, daphnetin is proven to inhibit the NF-κB signaling pathway and to inhibit the proliferation of HaCaT cells and the release of inflammatory factors, especially CCL20. This research showed that the modified microneedle loaded with daphnetin optimized transdermal drug delivery and relieved the symptoms of psoriasis more effectively. The novel route of Daph administration provides a future research direction for the treatment of psoriasis

Effects of Season, Parity and Days in Milk and Region on the Plasmin and Plasminogen Activity in Raw Milk

This study systematically investigated the effects of seasonal variation, parity, lactation stage, and production region on the plasmin (PL) and plasminogen (PG) activity in bovine raw milk. Raw milk samples were collected from an intensive dairy farm in Hohhot, Inner Mongolia to evaluate the impact of different seasons (summer and winter), lactation stages (initial, early and late) and parities (parities 1–4) on the plasmin activity and the transformation efficiency of PG. To examine the production region effect, another milk samples were collected from Ma’anshan, Anhui; Yinchuan, Ningxia; Harbin, Heilongjiang; and Changji, Xinjiang. Our results showed that season had no significant effect on the PL activity (P > 0.05) but significantly affected PG activation levels (P 0.05). Lactation stage had a significant impact on PG activation (P < 0.01); PG activity was 8.6% and 6.8% higher in the late stage than the initial and early stages, (5.67 ± 0.70) versus (5.22 ± 0.70) and (5.31 ± 0.67) U/L. Likewise, the geographical origin significantly impacted the conversion efficiency of PG (P < 0.05); PG activity was significantly higher in Harbin samples than in Yinchuan samples, (5.62 ± 0.88) versus (5.12 ± 1.19) U/L. Somatic cell count showed a weak positive correlation with both PL activity (r = 0.33) and PG activation (r = 0.21), suggesting that subclinical mastitis had a potential impact on them. This study revealed that both season and lactation stage affected milk stability by affecting the PG activation pathway, and the PL and PG activity in milk from high-latitude regions might be enhanced via the environment-physiology interaction. These findings provide a novel perspective for establishing a quality evaluation system for raw milk based on PL/PG regulation

Optic nerve head astrocytes contribute to vascular associated effects

PurposeThis study was conducted in order to test the expression of vasoactive substances within rat lamina cribrosa (LC) and optic nerve head (ONH) astrocytes, so as to investigate the role and potential mechanism of ONH astrocytes in vascular associated effects.MethodsLC tissue sections and primary cultured ONH astrocytes were obtained from adult Sprague-Dawley (SD) rats. Immunofluorescent staining was then used to detect the expression of vasoactive substances. Hyperoxia exposure was carried out both in vivo and in vitro, after which nitric oxide (NO) levels in LC tissue and cell supernatant were detected. The variations of protein and gene expression associated with vasoactive substances were subsequently tested. ONH astrocytes and vascular smooth muscle cells (VSMCs) were then incubated in a direct co-culture manner. Morphological parameters of VSMCs were finally analyzed in order to evaluate cell contraction.ResultsEndothelin-1 (ET-1), nitric oxide synthase (NOS) and renin-angiotensin system (RAS) were detected in both LC tissue and ONH astrocytes. Retinal vessel diameter was found obviously decreased following hyperoxia exposure. Moreover, hyperoxia inhibited NO production both in vivo and in vitro. ET-1 and RAS elements were observed to be upregulated, whereas NOS was downregulated. In ONH astrocytes and VSMCs co-culture system, the length-to-width ratio of VSMCs was shown to significantly increase on days 3 and 7 in hyperoxia compared with normoxia.ConclusionsThere is an abundance of expression of vasoactive substances within LC tissue and ONH astrocytes. The contractile response of VSMCs in the co-culture system provided direct evidence for the involvement of ONH astrocytes in vascular associated effects, which may signify a potentially novel direction for future research