The link between sea surface temperature (SST) gradients and atmospheric fronts is explored in a general circulation model across the Gulf Stream (GS) region from December to February 1981–2000. Two ...model experiments are analyzed, one with a realistic control SST distribution and one with a spatially smoothed SST distribution. The analysis shows a noticeable change in regional atmospheric frontal frequency between the two experiments (up to 30%), with the distribution of change exhibiting a clear imprint of the GS SST front. Further analysis of the surface sensible heat flux gradient across cold fronts reveals the pattern of change to be mediated by a thermal interaction between the oceanic and atmospheric fronts (“thermal damping and strengthening”). These results not only emphasize the significance of the GS SST gradient for storm development in the North Atlantic but also highlight the importance of resolution in assessing the role of frontal air‐sea interaction in midlatitude climate variability.
Key Points
Significant response in atmospheric frontal frequency to differently resolved Gulf Stream fronts
Atmospheric response consistent with a thermal air‐sea interaction mechanism
Strong implications for role of frontal air‐sea interaction in midlatitude climate variability
The storm-track response to sea surface temperature (SST) fronts in the northwestern Pacific region is investigated using an atmospheric general circulation model with a 50-km horizontal resolution. ...The following two experiments are conducted: one with 0.258 daily SST data (CNTL) and the other with smoothed SSTs over an area covering SST fronts associated with the Kuroshio, the Kuroshio Extension, the Oyashio, and the subpolar front (SMTHK). The storm track estimated from the local deepening rate of surface pressure (LDR) exhibits a prominent peak in this region in CNTL in January, whereas the storm-track peak weakens and moves eastward in SMTHK. Storm-track differences between CNTL and SMTHK are only found in explosive deepening events with LDR larger than 1 hPa h−1. A diagnostic equation of LDR suggests that latent heat release associated with large-scale condensation contributes to the storm-track enhancement. The SST fronts also affect the large-scale atmospheric circulation over the northeastern Pacific Ocean. The jet stream in the upper troposphere tends to meander northward, which is associated with positive sea level pressure (SLP) anomalies in CNTL, whereas the jet stream flows zonally in SMTHK. A composite analysis for the northwestern Pacific SLP anomaly suggests that frequent explosive cyclone development in the northwestern Pacific in CNTL causes downstream positive SLP anomalies over the Gulf of Alaska. Cyclones in SMTHK developing over the northeastern Pacific enhance the moisture flux along the west coast of North America, increasing precipitation in that region.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Aim: Sodium-glucose co-transporter 2 inhibitor (SGLT2i) therapy has been demonstrated to improve glycemic control and reduce body weight and fat mass in type 2 diabetes mellitus (T2DM). Here, our aim ...was to investigate the effects of SGLT2i dapagliflozin-treatment on body muscle mass and muscle fat content in patients with T2DM.Methods: We prospectively recruited uncontrolled (hemoglobin A1c HbA1c ＞7%) Japanese T2DM patients who had a body mass index (BMI) ＜35 kg/m2. Patients were treated with dapagliflozin (5 mg/day) or non-SGLT2i medicines for six months to improve HbA1c. We investigated changes in body composition using bioelectrical impedance analysis and changes in psoas muscle mass using abdominal computed tomography (CT).Results: Subjects were 50 T2DM patients (72% male) with a mean age of 56.1 years, mean BMI of 27.1 kg/m2 and mean HbA1c of 7.9%. HbA1c, body weight, and BMI were significantly decreased in both treatment groups, and the HbA1c decrease was not significantly different between groups. Dapagliflozin treatment significantly decreased body weight and total fat mass without affecting skeletal muscle mass. The absolute change in soft lean mass and skeletal muscle mass was not significantly different between groups. Dapagliflozin treatment did not significantly decrease psoas muscle index, and the absolute change in this index was not significantly different between groups. Dapagliflozin therapy also produced a significant increase in CT radiation attenuation in the third lumbar paraspinal muscles compared with non-SGLT2i therapy.Conclusions: Treatment with dapagliflozin for six months significantly improved glycemic control and reduced body weight without reducing muscle mass in T2DM patients.
In this article we investigate the influence of the Gulf Stream sea‐surface temperature (SST) front on the North Atlantic eddy‐driven jet and its variability, by analysing the NCEP‐CFSR dataset and a ...pair of AGCM simulations forced with realistic and smoothed Gulf Stream SST boundary conditions. The Gulf Stream SST front acts to generate stronger meridional eddy heat flux in the lower troposphere and an eddy‐driven jet over the eastern North Atlantic which is located further polewards than in the simulation with smoothed SST. The strong Gulf Stream SST gradient is found to be crucial in more accurately capturing the trimodal distribution of the eddy‐driven jet latitude, with the more poleward climatological jet being the result of the jet occupying the northern jet position more frequently in the simulation forced with observed SSTs. The more frequent occurrence of the northern jet location is associated with periods of high eddy heat flux over the Gulf Stream region. Composite analysis of high eddy heat flux events reveals that the significantly higher heat flux is followed by larger and more persistient poleward jet excursions in the simulations with realistic SSTs than in the simulation with smoothed SSTs, with upper‐tropospheric eddy momentum fluxes acting to maintain the more poleward eddy‐driven jet. Periods of high eddy heat flux over the Gulf Stream region are also shown to be associated with increased blocking frequency over Europe, which are clearly distinct from periods with a northern jet position.
Background
Anaplastic thyroid carcinoma (ATC) accounts for only 1 to 2% of all thyroid carcinomas, but it is one of the most lethal neoplasms in humans. To date, most findings about ATC have been ...derived from single-institution studies with limited numbers of cohorts. To obtain further insights into this “orphan disease,” we have established a multicenter registry, the ATC Research Consortium of Japan (ATCCJ). We analyzed prognostic factors and treatment outcomes using the large cohort database of the ATCCJ.
Methods
Most of the Japanese centers involved in the treatment of thyroid cancer were invited to join the ATCCJ and have provided information on ATC patients treated between 1995 and 2008. The database includes 677 cases from 38 registered institutions. Survival curves were determined using Kaplan-Meier methods and were compared using the log-rank test. Cox’s proportional hazards model was used for multivariate analysis.
Results
Clinical varieties of ATC were classified into four types: common type (
n
= 547); incidental type (
n
= 29); anaplastic transformation at the neck (
n
= 95); anaplastic transformation at a distant site (
n
= 6). The incidental type followed by anaplastic transformation at the neck showed better outcomes than the other types. Anaplastic transformation at a distant site showed the worst outcomes. The 6-month and 1-year cause-specific survival (CSS) rates for common-type ATC were 36 and 18%, respectively. In all, 84 (15%) achieved long-term (>1 year) survival. Multivariate analysis identified age ≥70 years, presence of acute symptoms, leukocytosis (white blood cell count ≥10,000/mm
3
), large tumor >5 cm, T4b tumor, and distant metastasis as significant risk factors for lower survival. CSS rates also differed significantly depending on UICC stages, with 6-month CSSs of 60% for stage IVA, 45% for IVB, and 19% for IVC. For 36 of 69 (52%) stage IVA patients who underwent radical surgery, adjuvant therapies, including radiation therapy (RTX) and chemotherapy (CTX) did not show additional benefit statistically. Conversely, among 242 stage IVB patients, 80 (33%) underwent radical surgery. For those patients, therapies combining RTX with CTX significantly improved CSS.
Conclusions
Long-term survival is possible for selected patients with ATC. To determine the treatment strategy, UICC stage (disease extent) and other prognostic factors (e.g., biologic malignancy grade) should be considered.
Background
Therapeutic strategy for patients with differentiated thyroid carcinoma (DTC) in Japan has differed from that in Western countries. Total thyroidectomy followed by radioactive iodine (RAI) ...ablation has been a standard therapy in Western countries, while limited thyroidectomy has been widely accepted in Japan. We newly established guidelines for clinical practice in treating thyroid tumors based on evidence from previous publications and the accumulation of data from patients in Japan. We present our therapeutic recommendations for DTC patients based on these guidelines.
Methods
From the 55 clinical questions (CQ) in our guideline, we selected CQ regarding the treatment of DTC. We commented on each and compared it with the corresponding regions in Western guidelines.
Results
For papillary carcinoma, we strongly or moderately recommend total thyroidectomy for patients with tumors larger than 4 cm, clinical node metastasis, distant metastasis, or significant extrathyroid extension, while hemithyroidectomy is acceptable for T1N0M0 patients. In contrast to Western guidelines, routine central compartment dissection is recommended for papillary carcinoma in our guidelines. Completion total thyroidectomy is recommended for patients who were scheduled for hemithyroidectomy under a preoperative diagnosis of follicular neoplasm and were pathologically confirmed as having follicular carcinoma if the pathological diagnosis indicated widely invasive carcinoma or carcinoma having poorly differentiated components. RAI ablation is also recommended for DTC with aggressive clinicopathological features, but its indication is narrower than that in Western guidelines, not only because of the limitations on RAI, but also because it is our policy that patients without high-risk features do not require RAI ablation.
Conclusion
It is important to treat DTC patients individually according to their clinicopathological features rather than uniformly. We hope that policies regarding the treatment of DTC patients in Western countries and Japan will find the optimal compromise in the future, leading to the best treatments for patients with thyroid carcinoma all over the world.
In radionuclide compounds undergoing electron capture (EC) decay, the electron density at the nucleus (ρ(0)) and half-life of the nucleus are inversely proportional. Thus, the decay can be ...accelerated by changing the chemical or physical conditions. A previous study reported a 1.1–1.5% reduction in the half-life of 7Be encapsulated in C60 compared with 7Be metal. However, 7Be was inserted into the fullerene using the rebound energy of the nuclear reaction, which may not be a practical method. This paper elucidates the mechanism of ρ(0) change in various Be compounds from density functional calculations and attempts to propose better systems that show faster EC decay (larger ρ(0)) and/or that are easier to generate than Be in C60. In typical Be compounds, ρ(0) decreases because Be donates electrons to other atoms through chemical bonds and, thus, is not effective. Among the various Be-encapsulated fullerenes (C20–C180), the largest increase in ρ(0) was obtained for C50 fullerene, but the magnitude was almost similar to that of C60. As new systems, we propose Be-encapsulated rare gas solids, which would be generated only by applying high pressure. An increase in ρ(0) from Be metal in the range 2–10%, which depends on the lattice constant, is obtained.
District heating and cooling (DHC) systems have attracted interest in reducing CO2 emissions. A fifth-generation DHC (5GDHC) system that supplies a heat-transport medium at a temperature close to the ...ground and uses various unused heat sources is proposed. Meanwhile, some DHC systems installed in Japan are first-generation DHC (1GDHC) systems that use fossil fuels as a heat source. Based on these scenarios, this study focuses on the energy-saving effects of introducing a CO2 network system in Tokyo, which is based on the same concepts as the 5GDHC systems. The purpose of this study is to estimate the utility value of unused heat sources for the CO2 network system. An analytical model is developed that calculates the energy consumption of the system under exogenous conditions, such as those for energy consumers and heat sources. Applying a model to a domestic urban area in Tokyo, where a conventional 1GDHC system was introduced, it was confirmed that for a total head of groundwater of 50 m, river water of 10 m, and sewage water of 10 m, the potential annual CO2 reduction is approximately 5,000 ton/y compared with the 1GDHC system. These values are feasible in Tokyo, and therefore, this system looks promising.
•Introduction potential of the CO2 network system in Tokyo are evaluated.•Utility value of groundwater, sewage water, and river water are estimated.•Optimum CO2 temperature is derived for the heat source temperature and heat demand.•Groundwater is the most favorable in Tokyo from the point of view of CO2 saving.•Annual CO2 emissions can be reduced by 40% with respect to the conventional system.
Objective Sodium-glucose co-transporter 2 (SGLT2) inhibitors reduce cardiovascular events and decrease the body fat mass in patients with type 2 diabetes mellitus (T2DM). We examined whether or not ...the SGLT2-inhibitor dapagliflozin can improve the endothelial function associated with a reduction in abdominal fat mass. Methods We prospectively recruited patients with uncontrolled hemoglobin A1c (HbA1c) >7.0% T2DM who were not being treated by SGLT2 inhibitors. Patients were treated with add-on dapagliflozin (5 mg/day) or non-SGLT2 inhibitor medicines for 6 months to improve their HbA1c. We measured the peripheral microvascular endothelial function as assessed by reactive hyperemia peripheral arterial tonometry (RH-PAT) and calculated the natural logarithmic transformed value of the RH-PAT index (LnRHI). We then investigated changes in the LnRHI and abdominal fat area using computed tomography (CT). Results The subjects were 54 patients with uncontrolled T2DM (72.2% men) with a mean HbA1c of 8.1%. The HbA1c was significantly decreased in both groups, with no significant difference between the groups. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly increased the LnRHI. The changes in the LnRHI were significantly greater in the dapagliflozin group than in the non-SGLT2 inhibitor group. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly decreased the abdominal visceral fat area, subcutaneous fat area (SFA), and total fat area (TFA) as assessed by CT and significantly increased the plasma adiponectin levels. The percentage changes in the LnRHI were significantly correlated with changes in the SFA, TFA, systolic blood pressure, and adiponectin. Conclusion Add-on treatment with dapagliflozin significantly improves the glycemic control and endothelial function associated with a reduction in the abdominal fat mass in patients with uncontrolled T2DM.
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