Impact of initial water vapor on the upscale growing process of a squall line in South China

During the spring and summer seasons, in the South China region where abundant water vapor is present, squall lines can rapidly develop into larger scales within a short period of time. In order to explore the influence of water vapor content on the process of squall line scale growth in South China, using the WRF model, a numerical simulation was conducted for a squall line system in South China on 11 May 2020. We investigated the effect of the variation of water vapor at different levels on its intensity and structure, and discussed the growth mechanism of the squall line system. This squall line occurred with the presence of high-level jet and low-level wind shear complementing each other, within an unstable layer of "dry at the high level and wet at the low level". The simulation showed that, in the early stage of the squall line development, a large maximum convective available potential energy (MCAPE) was observed in the southern part of the convection and coastal warm areas, which is beneficial for the accumulation of unstable energy here. Meanwhile, with the high low-level wind shear, the linear structure of the convection was well maintained. Subsequently, the squall line propagated southward and merged with warm region convection, resulting a further scale growth. Water vapor experiments showed that the MCAPE values are primarily influenced by the moisture content in the low-level atmosphere. More low-level moisture content causes stronger thunderstorm high pressure. Additionally, the presence of higher MCAPE values and larger low-level vertical wind shear contribute to the growth of convective cells in the post-convective stage, prolonging their existence. Reducing the mid-level water vapor content results in a decrease in intense surface precipitation, a weakening of convective intensity, and a quick dissipation into individual convective cells. But when the squall line moves into the area with high MCAPE values, it once again develops into a linear structure. Therefore, an increase in low-level moisture or a decrease in mid-level moisture favors the genesis of convection. However, reducing mid-level moisture results in relatively drier air at mid-levels, making it difficult for the linear structure to be sustained. Further investigation into the internal structure of the squall line reveals that vertical motion and rear inflow also influence the scale growth of the squall line. In the convective system analyzed in this study, the strong rearward inflow enhances the upward motion and generates forward outflow, leading to severe surface wind. Strengthening low-level moisture not only increases the size of the stratiform cloud region at the rear of the convection, but also leads to a stronger upward motion sustaining vertically, which promotes prolonged convective activity. On the other hand, reducing mid-level moisture weakens convective intensity and lowers the height of the echo tops. During the development stage, the rearward inflow intensifies, and dry cold air descends rapidly, leading to the strengthening of the surface cold pool, and causing strong winds due to the forward outflow

Drought losses in China might double between the 1.5 °C and 2.0 °C warming

We project drought losses in China under global temperature increase of 1.5 °C and 2.0 °C, based on the Standardized Precipitation Evapotranspiration Index (SPEI) and the Palmer Drought Severity Index (PDSI), a cluster analysis method, and “intensity-loss rate” function. In contrast to earlier studies, to project the drought losses, we predict the regional gross domestic product under shared socioeconomic pathways instead of using a static socioeconomic scenario. We identify increasing precipitation and evapotranspiration pattern for the 1.5 °C and 2.0 °C global warming above the preindustrial at 2020–2039 and 2040–2059, respectively. With increasing drought intensity and areal coverage across China, drought losses will soar. The estimated loss in a sustainable development pathway at the 1.5 °C warming level increases 10-fold in comparison with the reference period 1986–2005 and nearly threefold relative to the interval 2006–2015. However, limiting the temperature increase to 1.5 °C can reduce the annual drought losses in China by several tens of billions of US dollars, compared with the 2.0 °C warming

第790回千葉医学会例会・第一外科教室談話会 60.

<p>a) OCP; b) -0.85 V_SCE; c) -0.95 V_SCE; d) -1.05 V_SCE.</p

Efficacy of two different dosages of prednisone for treatment of subacute thyroiditis: a single-centre, prospective, randomized, open-label, non-inferiority trial

Introduction: The study aimed to explore the efficacy and safety of low-dose (LD) and regular-dose (RD) prednisone (PDN) for the treatment of subacute thyroiditis (SAT). Material and methods: Patients were randomly allocated using the block randomization method to the 2 groups. The primary outcome was the time required for PDN treatment. Secondary outcomes included percentages of relapse, mean score for the Morisky Medication Adherence Scale-8© (MMAS-8), time required for symptoms to resolve, cumulative PDN dose (mg), and mean erythrocyte sedimentation rate (ESR) at 2 weeks and at baseline. Results: The study cohort included 77 patients, randomized 74 participants, and 68 completed the study. There was no significant difference in the treatment duration between the LD and RD groups (55.31 ± 14.05 vs. 61.25 ± 19.95 days, p = 0.053). The mean difference in the time required for PDN treatment between the LD and RD groups was –1.86 [95% confidence interval (CI) = –10.64 to 6.92] days, which was within the non-inferiority margin of 7 days. There was a significant difference in the mean score for MMAS-8 between the LD and RD groups (5.84 ± 0.88 vs. 5.33 ± 1.12, p = 0.031). Also, there was a significant difference in the cumulative PDN dose between the LD and RD groups (504.22 ± 236.86 vs. 1002.28 ± 309.86, p = 0.046). The ESR at 2 weeks was statistically significant compared to baseline values in both groups, with pre-treatment and post-treatment ESRs of 49.91 ± 24.95 and 17.91 ± 12.60/mm/h, (p &lt; 0.0001) in the LD group and 65.08 ± 21.77 and 17.23 ± 13.61/mm/h (p &lt; 0.0001) in the RD group. Conclusion: Low-dose PDN therapy may be sufficient to achieve complete recovery and better outcomes for SAT. This study is registered with the Chinese Clinical Trial Registry (02/10/2021 ChiCTR2100051762)

Hypo-high density lipoproteinemia is a predictor for recurrent stroke during the long-term follow-up after revascularization in adult moyamoya disease

ObjectivePrevious studies have reported that hypo-high-density lipoproteinemia (HHDL) was an independent risk factor for the cerebrovascular event. However, the risk of HHDL for stroke recurrence in moyamoya disease (MMD) during long-term follow-up after revascularization remains poorly understood. We aim to investigate the association between HHDL and stroke recurrence in adult patients with MMD.MethodsA total of 138 adult patients with MMD were prospectively recruited from 1 July to 31 December 2019. After excluding 15 patients who did not meet the inclusion criteria, all the 123 patients were enrolled. Participants were grouped according to the stroke recurrence and HHDL presentation, respectively. Clinical data and laboratory examinations were compared by the statistical analysis. The Kaplan–Meier survival analysis was conducted to compare the stroke-free survival rates between participants with HHDL and those without. Univariate and multivariate logistic regression analyses were performed to identify independent factors of the neurological status. Univariate and multivariate Cox regression analyses were conducted to identify the predictors for the recurrent stroke.ResultsParticipants with recurrent stroke group showed a lower level of high-density lipoprotein (HDL) (p = 0.030). More participants in the recurrent stroke group had HHDL (p = 0.045). What is more, there was statistical significance in the Kaplan–Meier curve of stroke incidence between the normal HDL group and the HHDL group (log-rank test, p = 0.034). Univariate logistic analysis results showed that HHDL (OR 0.916, 95% CI 0.237–3.543; p = 0.899) and HDL (OR 0.729, 95% CI 0.094–5.648; p = 0.763) were not predictive factors for the neurological status. In the multivariate Cox regression analysis, diabetes (HR 4.195, 95% CI 1.041–16.899; p = 0.044), HDL (HR 0.061, 95% CI 0.006–0.626; p = 0.019), and HHDL (HR 3.341, 95% CI 1.110–10.051; p = 0.032) were independent risk factors for the recurrent stroke.ConclusionsHypo-high-density lipoproteinemia might be a predictor or the potential therapeutic target for recurrent stroke during the long-term follow-up after revascularization in adult patients with MMD

Enhanced Effect of NaOH/Thiourea/Urea Aqueous Solution on Paper Strength of High Yield Pulp

In this work, the thermomechanical pulp of Pinus massoniana was pretreated with a NaOH/thiourea/urea aqueous solution to promote fiber bonded area and to increase paper strength. The effects of pulp concentration, alkali dosage, dipping time, and freezing time were evaluated through single factor experiments. The optimum conditions were found to be 15% pulp consistency, 8% NaOH, a dipping time of 15 min, and a freezing time of 60 min. Under these conditions, the paper tensile and burst index of treated pulp increased nearly 100%, and the bulk also was reduced by 10%, but there were no significant effects on folding

Modifying the Refining Energy Consumption of Chemi-Mechanical Pulping with NaOH-Thiourea-Urea Aqueous Solution

To reduce the refining energy consumption of chemi-mechanical pulping, treatment with NaOH-thiourea-urea aqueous solution was studied in this work. By means of single-factor experiments, the effects of alkali dosage, soaking time, and freezing time were evaluated. It was found that the optimal conditions were an alkali dosage of 8%, soaking time of 45 min, and freezing time of 105 min. The results revealed that refining energy consumption could be reduced by approximately 40% under optimal conditions compared with that of alkaline peroxide mechanical pulp, while other pulping or paper-making properties were similar. There were no significant effects on the structure of the functional groups, the crystalline region of the pulp, or the whole structure of the treated wood chips. However, damage to single wood fibers on the chips treated in NaOH-thiourea-urea aqueous solution was more obvious

NaOH-Thiourea Aqueous Solution Treatment of Cellulose Fiber and its Effects on Bulk and Softness

Bleached kraft pulp of hardwood was pretreated in a NaOH-thiourea aqueous solution to modify the bulk and softness of the cellulose fibers with minimal reduction in paper strength. The effects of soaking time, fiber concentration, alkali dosage, and freezing time were evaluated through single factor experiments. The optimal conditions were determined to be a soaking time of 15 min, fiber concentration of 15%, alkali dosage of 9%, and freezing time of 75 min. Under the optimal conditions, the bulk and softness of the treated cellulose fibers were increased by 28.7% and 21.6%, respectively, compared with those of untreated cellulose fibers. The tensile and burst indices were only reduced by 1.2% and 5.1%, respectively, under these conditions. Also, there were almost no effects on the polymerization degree, the thermostability, and the structure of the functional groups or crystalline regions

Convective-stratiform rainfall separation of Typhoon Fitow (2013): A 3D WRF modeling study

Surface precipitation budget equation in a three-dimensional (3D) WRF model framework is derived. By applying the convective-stratiform partition method to the surface precipitation budget equation in the 3D model, this study separated convective and stratiform rainfall of typhoon Fitow (2013). The separations are further verified by examining statistics of vertical velocity, surface precipitation budget, and cloud microphysical budget. Results show that water vapor convergence moistens local atmosphere and offsets hydrometeor divergence, and producing convective rainfall, while hydrometeor convergence primarily supports stratiform rainfall, since water vapor divergence and local atmospheric drying generally cancelled out. Mean ascending motions are prevailing in the entire troposphere in the convective region, whereas mean descending motions occur below 5 km and mean ascending motions occur above in the stratiform region. The frequency distribution of vertical velocity shows vertical velocity has wide distribution with the maximum values up to 13 m s-1 in the convective regions, whereas it has narrow distribution with absolute values confined within 7 m s-1 in the stratiform region. Liquid cloud microphysics is dominant in convective regions and ice cloud microphysics is dominant in stratiform regions. These indicate that the statistics results are generally consistent with the corresponding physical characteristics of the convective-stratiform rainfall structures generalized by previous studies

Preparation of Wet Strength Paper from Filter Paper with NaOH-Thiourea-Urea Aqueous Solution

In this work, wet strength paper was prepared from quantitative filter paper pretreated with NaOH-thiourea-urea aqueous solution. The effects of alkali concentration, soaking time, freezing time, and washing time were evaluated through single factor experiments. The optimum conditions were found to be an alkali concentration of 8%, soaking time of 2 seconds, freezing time of 15 minutes, and washing time of 10 minutes. Under these conditions, the wet tensile strength of the modified paper could be increased to 33% of the dry tensile strength and 400% of the wet tensile strength of the body paper. Also, the wet burst strength could be improved to 200% of the dry burst strength and 2400% of the wet burst strength of the body paper. However, there were no significant effects on the structure of the functional groups or crystalline region. Also, there was no toxic material released during the treatment, and the treatment solution was recyclable and environmentally friendly