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The parameterizations of air‐sea turbulent heat flux are one of the major bottlenecks in atmosphere‐ocean coupled model development, which play a crucial role in sea surface temperature (SST) prediction. Recently, neural networks start to be applied for the development of parameterizations of interface turbulent heat flux. However, these new parameterizations are primairily developed for specific regions and have not been tested in real atmosphere‐ocean coupled models. In this study, we propose a new air‐sea heat flux parameterization using a physical‐informed neural network (PINN) based on multiple observational data sets worldwide. Evaluated with an independent observation data set, it is shown that the PINN can significantly reduce the RMSE of latent heat flux by at least about 48.6% compared to three traditional bulk formulas. Moreover, the PINN can be flexibly updated with new observational data by transfer learning. To test the performance of the new parameterization in realistic application, we implement the PINN into a global ocean‐atmosphere coupled model and make seasonal forecasts for the first time. The PINN markedly reduce the errors of equatorial SST forecast, indicating a good performance of the PINN‐based air‐sea turbulent heat flux scheme. Noticeably, due to limited observational data, the NN‐based parameterizations tend to underestimate heat flux at high wind speeds compared with bulk formula‐based parameterizations. With more data available at extreme conditions, the PINN can be improved via transfer learning and need to be futher evaluated. This study suggests that PINN‐based air‐sea heat flux parameterization is promising to improve SST simulation. Plain Language Summary: The air‐sea turbulent heat flux plays a crucial role in advancing marine science and is the key to improving the accuracy of the sea surface temperature (SST) prediction. The traditional parameterizations for air‐sea turbulent heat flux have large deviations in some circumstances and are hard to update since they are developed based on unique observation datasets. The emergence of artificial intelligence offers a fresh avenue to address this issue. In this study, we develop air‐sea heat flux parameterization based on a PINN and multiple observational data sets, which measured air‐sea heat fluxes directly. Our novel parameterization outperforms three bulk formula‐based parameterizations in offline tests and solves the problem of unphysical result of neural networks. The new parameterization also shows great potential in improving the accuracy of SST prediction in multiple online tests. Key Points: We propose a new air‐sea turbulent heat flux parameterization based on physical‐informed neural network (PINN) which is trained on data in situThe new scheme can accurately calculate the air‐sea turbulent heat flux and perform well in a global seasonal forecastThe PINN can be flexibly updated with new observational data by transfer learning [ABSTRACT FROM AUTHOR]

Objective: We aimed to examine whether HIV infection was independently associated with frailty status and its individual components. Methods: This cross‐sectional investigation included people living with HIV (PLWH) and HIV‐negative individuals from the baseline survey of the Comparative HIV and Aging Research in Taizhou (CHART) cohort, China. Frailty phenotype was based on five components: weight loss, low physical activity, exhaustion, weak grip strength and slow gait speed. Frailty was defined as the presence of at least three components, and prefrailty was defined as one or two components. Logistic regression models were used to analyse the factors associated with frailty and its components. Results: In all, 2475 people living with HIV (age 45.5 ± 14.9 years; 76.2% male) and 4948 HIV‐negative individuals (age 45.5 ± 14.8 years; 76.3% male) were included. Among PLWH, median CD4 count was 395 cells/μL and 78% were currently on antiretroviral therapy (ART). Frailty and prefrailty were significantly more prevalent in PLWH (3.2% vs 1.9% and 32.9% vs 27.9%) overall and at ages 18–39 (1.4% vs 0.2% and 22.7% vs 19.0%), 40–59 (2.5% vs 0.9% and 30.9% vs 27.9%) and 60–90 years (8.4% vs 7.4% and 57.1% vs 45.8%). HIV infection was associated with frailty and prefrailty [adjusted odds ratio (aOR) = 1.48, 95% confidence interval (CI): 1.06–2.08; and aOR = 1.18, 95% CI: 1.05–1.33, respectively] after adjusting for confounding variables, but were strengthened with further adjustment for multimorbidity (aOR = 1.62, 95% CI: 1.14–2.28; and aOR = 1.22, 95% CI: 1.09–1.37), and were no longer significant with further adjustment for depressive symptoms and sleep disorders (aOR = 1.02, 95% CI: 0.71–1.46; and aOR = 1.06, 95% CI: 0.94–1.20). Among individual components, HIV infection was positively associated with weak grip strength and slow gait speed, but negatively associated with low physical activity and exhaustion in all the adjusted models described. Conclusions: Frailty and prefrailty occur more often and earlier in PLWH. However, grip strength and gait speed are affected to a greater extent, highlighting their potential as screening and intervention targets to prevent or slow frailty among PLWH. [ABSTRACT FROM AUTHOR]

Sea-spray-mediated heat flux plays an important role in air–sea heat transfer. Heat flux integrated over the droplet size spectrum can simulate well the total heat flux induced by sea spray droplets. Previously, a fast algorithm of spray flux assuming single-radius droplets (A15) was widely used, as the full-size spectrum integral is computationally expensive. Based on the Gaussian quadrature (GQ) method, a new fast algorithm (SPRAY-GQ) of sea-spray-mediated heat flux is derived. The performance of SPRAY-GQ is evaluated by comparing heat fluxes with those estimated from the widely used A15. The new algorithm shows a better agreement with the original spectrum integral. To further evaluate the numerical errors of A15 and SPRAY-GQ, the two algorithms are implemented into the coupled Climate Forecast System model version 2.0 (CFSv2.0) and WAVEWATCH III (WW3) system, and a series of 56 d simulations in summer and winter are conducted and compared. The comparisons with satellite measurements and reanalysis data show that the SPRAY-GQ algorithm could lead to more reasonable simulation than the A15 algorithm by modifying air–sea heat flux. For experiments based on SPRAY-GQ, the sea surface temperature at middle to high latitudes of both hemispheres, particularly in summer, is significantly improved compared with the experiments based on A15. The simulation of 10 m wind speed and significant wave height at middle to low latitudes of the Northern Hemisphere after the first 2 weeks is improved as well. These improvements are due to the reduced numerical errors. The computational time of SPRAY-GQ is about the same as that of A15. Therefore, the newly developed SPRAY-GQ algorithm has potential to be used for the calculation of spray-mediated heat flux in coupled models. [ABSTRACT FROM AUTHOR]

Accurate calculation of the whitecap fraction is of great importance for the estimation of air-sea momentum flux, heat flux and sea-salt aerosol flux in Earth system models. Past whitecap fraction parameterizations were mostly power functions of wind speed, lacking consideration of other factors, while the single wind speed dependence makes it difficult to explain the variability of the whitecap fraction. In this work, we constructed a novel multivariate whitecap fraction parameterization using a deep neural network, which is diagnosed and interpreted. Compared with a recent developed parameterization by Albert and coworkers, the new parameterization can reduce the computational error of the whitecap fraction by about 15%, and it can better characterize the variability of the whitecap fraction, which provides a reference for the uncertainty study of sea-salt aerosol estimation. Through a permutation test, we ranked the importance of different input variables and revealed the indispensable role of variables such as significant wave height, sea surface temperature, etc., in the whitecap fraction parameterization. [ABSTRACT FROM AUTHOR]

Hypertension is highly prevalent among people living with HIV (PLWH). We sought to characterize the hypertension incidence among PLWH on antiretroviral therapy, focusing on the effect of change in general and abdominal obesity on hypertension during follow-up. This was a prospective analysis of 229 treated PLWH aged over 40 years without hypertension at baseline. Overall a median follow-up of 2.9 years, 26.2% PLWH developed hypertension. In multivariable models, compared to those without obesity measures at both baseline and follow-up visit, PLWH with general obesity at both occasions (adjusted odds ratio [aOR] = 3.83, P = 0.006) or at baseline only (aOR = 5.45, P = 0.003), abdominal obesity (measured as waist circumference) at both occasions (aOR = 3.87, P = 0.001) or at follow-up only (aOR = 2.27; 9P = 0.060), abdominal obesity (measured as waist-to-hip ratio) at both occasions (aOR = 2.27, P = 0.077) were at increased risk of incident hypertension. Our data show that both general and abdominal obesity especially in the persistent status increase the hypertension risk in treated PLWH. [ABSTRACT FROM AUTHOR]

Ocean surface gravity waves have enormous effects on physical processes at the atmosphere-ocean interface. The effects of wave-related processes on global intraseasonal prediction were evaluated after we incorporated the WAVEWATCH III model into the Climate Forecast System model version 2.0 (CFSv2.0), with the Chinese Community Coupler version 2.0. Several major wave-related processes, including the Langmuir mixing, Stokes-Coriolis force with entrainment, air-sea fluxes modified by Stokes drift and momentum roughness length, were evaluated in two groups of 56-day experiments, one for boreal winter and the other for boreal summer. Comparisons were performed against in-situ buoys, satellite measurements and reanalysis data, to evaluate the influence of waves on intraseasonal prediction of sea surface temperature (SST), 2-m air temperature (T02), mixed layer depth (MLD), 10-m wind speed (WSP10) and significant wave height (SWH) in CFSv2.0. Overestimated SST and T02, as well as underestimated MLD in mid and high latitudes in summer from original CFSv2.0 are clearly improved, mainly due to enhanced vertical mixing generated by Stokes drift. The largest regional mean SST improvement reaches 35.89 % in the Southern Ocean. For WSP10 and SWH, the wave-related processes generally lead to reduction of biases in regions where wind speed and SWH are overestimated. The decreased SST caused by Stokes drift-related mixing stabilizes marine atmospheric boundary layer, weakens wind speed and then SWH. Compared with the NDBC buoy data, the overestimated WSP10 is improved by up to 13.52 % in boreal summer. The increased roughness length due to waves leads to some reduction in the originally overestimated wind speed and SWH, with the largest SWH improvement of 11.93 % and 20.05 % in boreal winter and summer respectively. The effects of Stokes drift and current on air-sea fluxes are investigated separately. Their overall effects on air-sea fluxes reduce the overestimated WSP10 by up to 17.31 % and 23.21 % in boreal winter and summer respectively. These cases are helpful for the future development of the two-way CFS-wave coupled system. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to evaluate the association between triglyceride glucose-waist height ratio (TyG-WHtR) index and the prevalence of gallstone disease (GSD), alongside the age at first gallstone surgery among adult populations within the United States., Methods: We screened participants using the National Health and Nutrition Examination Survey (NHANES). Logistic regression analysis, generalized additive modeling, smoothed curve fitting, and subgroup analysis were employed to assess the association between the TyG-WHtR index, prevalence of GSD, and the age at initial gallstone surgical intervention., Results: In this study, 3,728 participants were enrolled, among whom 395 individuals reported a prior history of GSD. The association between the TyG-WHtR index and the prevalence of GSD demonstrated a non-linear, positive association. After adjusting for all potential confounders, for each incremental unit rise in the TyG-WHtR index, there was a 47% escalation in the prevalence of GSD (OR = 1.47, 95% CI: 1.29, 1.68). Subgroup analyses indicated a more pronounced association between the TyG-WHtR index and the prevalence of GSD among individuals aged 20-80 years, females, non-Hispanic white population, non-Hispanic black population, other racial groups, and non-diabetic cohorts. Additionally, this study identified that the TyG-WHtR index may be negatively correlated with age at first surgical treatment of gallstones., Conclusion: An elevated TyG-WHtR index demonstrates a positive association with the prevalence of GSD. However, more prospective studies are needed to validate our findings., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Chen, Chen, Qin, Hu, Zeng, Luo, Yang, Luo, Yuan, Shi and Wang.)

Background: Benign tumors of the spleen are rare compared to those of other parenchymal organs, accounting for less than 0.007% of all tumors, and are often found incidentally. Splenolymphangiomas are much rarer, commonly occur in children, and tend to have multiple foci. Splenic lymphangiomas are rare in adults, and fewer than 20 adult patients with isolated splenic lymphangiomas have been reported. In this article, we report the case of a middle-aged female patient with isolated splenic lymphangioma who underwent laparoscopic anatomical hypophysectomy of the lower pole of the spleen. We also summarize the existing literature on splenic lymphangioma diagnosis and available treatment options., Case Presentation: A 58-year-old middle-aged woman was found to have a mass approximately 60 mm in diameter at the lower pole of the spleen during a health checkup that was not accompanied by other symptoms or examination abnormalities. After completing a preoperative examination with no contraindications to surgery, the patient underwent laparoscopic anatomical splenectomy of the lower extremity of the spleen. The patient recovered well without complications and was discharged from the hospital on the 7th postoperative day. Histopathological and immunohistochemical results confirmed the diagnosis of splenic lymphangioma. Prompt surgical intervention is safe and necessary when splenic lymphangiomas are large or associated with a risk of bleeding., Conclusion: Splenic lymphangiomas are rare and require early surgical intervention in patients with large tumor diameters or those at risk of rupture and bleeding. After rigorous preoperative evaluation and preparation, laparoscopic anatomical partial splenectomy is safe and feasible for surgeons with experience in laparoscopic surgery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shi, Yang, Guo, Tang, Luo, Qin, Jiang, Huang, Gao, Zeng and Wang.)

Background: Fangcang shelter hospitals are quarantine facilities offering primary medical treatment for mild and asymptomatic SARS-CoV-2 cases. Little is known about the age-specific prevalence of insomnia among patients in Fangcang shelter hospitals, particularly in older age groups., Methods: This cross-sectional study was conducted in the three largest Fangcang shelter hospitals during the lockdown period, from March to May 2022, in Shanghai. The patients' demographic and medical information was recorded. Insomnia was defined according to the prescriptions for zolpidem and estazolam. The overall and age-specific prevalence and the risk factors of insomnia were investigated through regression models., Results: A total of 2,39,448 patients were included in this study (59.09% of the patients were male, the median age was 42, and 73.41% of the patients were asymptomatic), with the prevalence of insomnia being 3.1%. The prevalence of insomnia varied across different age groups (<18 years: 0.23%, 18-64 years: 2.64%, and ≥65 years: 10.36%). SARS-CoV-2 vaccine, regardless of the number of doses, was significantly associated with a decreased risk of insomnia for the group aged ≥65 years. Three doses of the vaccine reduced the risk of insomnia for patients aged 18-64 years. An extra day in the hospital significantly increased the risk of insomnia by approximately 10% for all age groups. Mild symptoms were significantly associated with a higher risk of insomnia among patients aged <65 years old, while being male and residing in the surrounding area were negatively associated with insomnia for all adults., Conclusion: This study observed that older patients were a high-risk population for developing insomnia in Fangcang shelter hospitals. SARS-CoV-2 vaccination might decrease the risk of insomnia in adults, especially the older adult, which indicates the benefits of vaccination for reducing insomnia among infected patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shi, Wang, Chen, Yang, Jing, Shang, Chen and Zhou.)

Idiopathic mesenteric phlebosclerosis (IMP) is an extremely rare disease with an unclear pathogenesis and risk factors. The clinical manifestations of IMP are mostly non-specific, mainly consisting of digestive symptoms such as abdominal pain, bloating and diarrhea. The diagnosis of IMP mainly relies on abdominal computed tomography (CT) and colonoscopy. Pathological changes associated with IMP often involve fibrous degeneration of the venous wall, which results in the thickening of the colonic wall and longitudinal calcification of the mesenteric arteries. Currently, there is no standard treatment protocol for IMP, and nonsurgical treatment is the mainstay of most medical centers. In this study, we reported a case of a 55-year-old female patient with IMP whose main clinical presentation was recurrent abdominal pain. The patient's initial diagnosis was considered an incomplete intestinal obstruction and received non-surgical treatments; however, the efficacy of the treatment was unsatisfactory. After completing abdominal CT and colonoscopy, we excluded common diseases of the digestive system (e.g., tumors, Crohn's disease), and finally considered that this patient had a high likelihood of IMP. This patient eventually underwent laparoscopic enlarged right hemicolectomy due to recurrent symptoms and poor outcomes of non-surgical treatment. Postoperative pathological results confirmed the diagnosis of IMP. During the follow-up period, the patient recovered well without recurrence of IMP. Furthermore, we have reviewed the literature related to IMP and summarized the etiology, risk factors, diagnostic methods, treatment options and prognosis of IMP., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Tong, Shi, Zeng, Luo, Yang, Cai, Wang, Luo and Wang.)