Three-dimensional structure of the milky way dust: modeling of LAMOST data

We present a three-dimensional modeling of the Milky Way dust distribution by fitting the value-added star catalog of LAMOST spectral survey. The global dust distribution can be described by an exponential disk with scale-length of 3,192 pc and scale height of 103 pc. In this modeling, the Sun is located above the dust disk with a vertical distance of 23 pc. Besides the global smooth structure, two substructures around the solar position are also identified. The one located at $150^{\circ}<l<200^{\circ}$ and $-5^{\circ}<b<-30^{\circ}$ is consistent with the Gould Belt model of \citet{Gontcharov2009}, and the other one located at $140^{\circ}<l<165^{\circ}$ and $0^{\circ}<b<15^{\circ}$ is associated with the Camelopardalis molecular clouds.Comment: 15 pages, 6 figure, accepted by Ap

Declining glaciers endanger sustainable development of the oases along the Aksu-Tarim River (Central Asia)

Tarim River basin is the largest endorheic river basin in China. Due to the extremely arid climate the water supply solely depends on water originating from the glacierised mountains with about 75% stemming from the transboundary Aksu River. The water demand is linked to anthropogenic (specifically agriculture) and natural ecosystems, both competing for water. Ongoing climate change significantly impacts the cryosphere. The mass balance of the glaciers in Aksu River basin was clearly negative since 1975. The discharge of the Aksu headwaters has been increasing over the last decades mainly due to the glacier contribution. The average glacier melt contribution to total runoff is 30–37% with an estimated glacier imbalance contribution of 8–16%. Modelling using future climate scenarios indicate a glacier area loss of at least 50% until 2100. River discharge will first increase concomitant with glacier shrinkage until about 2050, but likely decline thereafter. The irrigated area doubled in the Aksu region between the early 1990s and 2020, causing at least a doubling of water demand. The current water surplus is comparable to the glacial runoff. Hence, even if the water demand will not grow further in the future a significant water shortage can be expected with declining glacial runoff. However, with the further expansion of irrigated agriculture and related industries, the water demand is expected to even further increase. Both improved discharge projections and planning of efficient and sustainable water use are necessary for further socioeconomic development in the region along with the preservation of natural ecosystems

Development of Threshold Levels and a Climate-Sensitivity Model of the Hydrological Regime of the High-Altitude Catchment of the Western Himalayas, Pakistan

Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the precipitation decreased. A two-dimensional visualization of the Pardé coefficient showed extreme drought events, and indicated greater sensitivity of the hydrological regime to temperature than to precipitation. The threshold levels of runoff for Zones I and II were 320 and 363 mm using the Q80 fixed method, while the mean runoff amounts were estimated to be 79.95 and 55.61 mm, respectively. The transient threshold levels varied by month, and the duration of droughts in Zones I and II ranged from 26.39 to 78.98 days. The sensitivity of the hydrological regime was estimated based on a modified climate-elasticity model (εp = 0.11–0.23, εt = −0.04–2.39) for Zones I and II, respectively. These results highlight the sensitivity of the hydrological regime to temperature, which influences the melting process. However, it is important to establish thresholds for hydrological variables and understand the climate sensitivity of the hydrological regime of the entire basin, so that policy makers and water managers can make sustainable water-resource-management decisions for this region

Characteristics of High-density Lipoprotein Subclasses Distribution for Subjects with Desirable Total Cholesterol Levels

<p>Abstract</p> <p>Background</p> <p>To investigate alteration of high density lipoproteins (HDL) subclasses distribution in different total cholesterol (TC) levels, mainly the characteristics of HDL subclasses distribution in desirable TC levels and analyze the related mechanisms.</p> <p>Methods</p> <p>ApoA-I contents of plasma HDL subclasses were determined by 2-dimensional gel electrophoresis coupled with immunodetection. 486 Chinese Adults subjects were assigned to different TC groups according to the third Report of NCEP (ATP- III) guidelines.</p> <p>Results</p> <p>The increase in contents of small preβ₁-HDL, HDL_3c, HDL_3b, and HDL_3aparticles clustered and reduce in HDL_2bwith increased of TC. The distribution of HDL subclasses have shown abnormality characterized by the lower HDL_2b(324.2 mg/L) contents and the higher preβ₁-HDL (90.4 mg/L) contents for desirable TC Chinese subjects. Among 176 desirable TC subjects, 58.6% subjects with triglyceride (TG) < 2.26 mmol/L, 61.2% subjects with HDL-C ≥1.03 mmol/L and 88.6% subjects with low density lipoprotein cholesterol(LDL-C) < 3.34 mmol/L, and the profile of HDL subclasses distribution for above these subjects was reasonable.</p> <p>Conclusions</p> <p>The particles size of HDL subclasses shifted towards smaller with increased TC levels. The TC was liner with HDL_2bcontents and those can be reduced 17 mg/L for 0.5 mmol/L increment in TC levels. The HDL subclasses distribution phenotype was not expectation for Chinese Population with desirable TC levels. Thus, from the HDL subclasses distribution point, when assessing the coronary heart disease(CHD) risk not only rely on the TC levels, but also the concentrations of TG, HDL-C and LDL-C must considered in case the potential risk for desirable TC subjects with other plasma lipids metabolism disorders.</p

The impact of plasma triglyceride and apolipoproteins concentrations on high-density lipoprotein subclasses distribution

<p>Abstract</p> <p>Objective</p> <p>To investigate the effect of triglyceride (TG) integrates with plasma major components of apolipoproteins in HDL subclasses distribution and further elicited the TG-apolipoproteins (apos) interaction in the processes of high density lipoprotein (HDL) mature metabolic and atherosclerosis related diseases.</p> <p>Methods</p> <p>Contents of plasma HDL subclasses were quantities by two-dimensional gel electrophoresis associated with immunodetection in 500 Chinese subjects.</p> <p>Results</p> <p>Contents of preβ₁-HDL, HDL_3a, and apoB-100 level along with apoB-100/A-I ratio were significantly increased, whereas there was a significant reduction in the contents of HDL₂, apoA-I level as well as apoC-III/C-II ratio with increased TG concentration. Moreover, preβ₁-HDL contents is elevated about 9 mg/L and HDL_2bcontents can be reduced 21 mg/L for 0.5 mmol/L increment in TG concentration. Moreover, with increase of apoA-I levels, HDL_2bcontents were marginally elevated in any TG concentration group. Furthermore, despite of in the apoB-100/A-I < 0.9 group, the contents of preβ₁-HDL increased, and those of HDL_2bdecreased significantly for subjects in both high and very high TG levels compared to that in normal TG levels. Similarly, in the apoB-100/A-I ≥ 0.9 group, the distribution of HDL subclasses also showed abnormality for subjects with normal TG levels.</p> <p>Conclusions</p> <p>The particle size of HDL subclasses tend to small with TG levels increased which indicated that HDL maturation might be impeded and efficiency of reverse cholesterol transport(RCT) might be weakened. These data suggest that TG levels were not only significantly associated with but liner with the contents of preβ₁-HDL and HDL_2b. They also raise the possibility that the TG levels effect on HDL maturation metabolism are subjected to plasma apolipoproteins and apolipoproteins ratios.</p

Association of the low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio and concentrations of plasma lipids with high-density lipoprotein subclass distribution in the Chinese population

<p>Abstract</p> <p>Background</p> <p>To evaluate the relationship between the low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C) ratio and HDL subclass distribution and to further examine and discuss the potential impact of LDL-C and HDL-C together with TG on HDL subclass metabolism.</p> <p>Results</p> <p>Small-sized preβ₁-HDL, HDL_3band HDL_3aincreased significantly while large-sized HDL_2aand HDL_2bdecreased significantly as the LDL-C/HDL-C ratio increased. The subjects in low HDL-C level (< 1.03 mmol/L) who had an elevation of the LDL-C/HDL-C ratio and a reduction of HDL_2b/preβ₁-HDL regardless of an undesirable or high LDL-C level. At desirable LDL-C levels (< 3.34 mmol/L), the HDL_2b/preβ₁-HDL ratio was 5.4 for the subjects with a high HDL-C concentration (≥ 1.55 mmol/L); however, at high LDL-C levels (≥ 3.36 mmol/L), the ratio of LDL-C/HDL-C was 2.8 in subjects, and an extremely low HDL_2b/preβ₁-HDL value although with high HDL-C concentration.</p> <p>Conclusion</p> <p>With increase of the LDL-C/HDL-C ratio, there was a general shift toward smaller-sized HDL particles, which implied that the maturation process of HDL was blocked. High HDL-C concentrations can regulate the HDL subclass distribution at desirable and borderline LDL-C levels but cannot counteract the influence of high LDL-C levels on HDL subclass distribution.</p

High-density lipoprotein subclass and particle size in coronary heart disease patients with or without diabetes

BACKGROUND: A higher prevalence of coronary heart disease (CHD) in people with diabetes. We investigated the high-density lipoprotein (HDL) subclass profiles and alterations of particle size in CHD patients with diabetes or without diabetes. METHODS: Plasma HDL subclasses were quantified in CHD by 1-dimensional gel electrophoresis coupled with immunodetection. RESULTS: Although the particle size of HDL tend to small, the mean levels of low density lipoprotein cholesterol(LDL-C) and total cholesterol (TC) have achieved normal or desirable for CHD patients with or without diabetes who administered statins therapy. Fasting plasma glucose (FPG), triglyceride (TG), TC, LDL-C concentrations, and HDL(3) (HDL(3b) and (3a)) contents along with Gensini Score were significantly higher; but those of HDL-C, HDL(2b+preβ2), and HDL(2a) were significantly lower in CHD patients with diabetes versus CHD patients without diabetes; The preβ(1)-HDL contents did not differ significantly between these groups. Multivariate regression analysis revealed that Gensini Score was significantly and independently predicted by HDL(2a), and HDL(2b+preβ2). CONCLUSIONS: The abnormality of HDL subpopulations distribution and particle size may contribute to CHD risk in diabetes patients. The HDL subclasses distribution may help in severity of coronary artery and risk stratification, especially in CHD patients with therapeutic LDL, TG and HDL levels