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Precipitation is particularly scarce in arid Central Asia (CA), and is expected to be severely impacted by future warming, and the assessment of the stationarity of precipitation variability is important for managing surface water resources in this region. In this study, we investigated the statistics of stationarity in the totals and extremes of precipitation in CA based on the longest observational records (1881–2006), tree-ring reconstructed records (1756–2012 and 1760–2015), and the Coupled Model Intercomparison Project 5 (CMIP5) simulations, applying the autocorrelation function and testing criteria established based on the statistical definitions of stationarity. We analyzed the longest daily precipitation record (Tashkent station, 1881–2006) and found that the autocorrelation coefficient of the precipitation totals (PRCPTOT) and annual maximum 1-day precipitation amount (Rx1day) were statistically insignificant for all lags, implying stationary behavior. Regionally, nearly all the Global Historical Climatology Network-Daily Database (GHCN-D) observatory sites (1925–2005) indicated likely stationary behavior. The reconstructed records were also indistinguishable from a random process. For the CMIP5 models, the simulated and projected PRCPTOT closely approximated a purely random process; however, the projected Rx1day maintained non-stationary means in most of the models under the representative concentration pathway (RCPs), implying that extreme events would increase in the future. The mean precipitation changes (ΔP) can be expressed as an exponential function depending on the length of the successive mean periods ( μ ) and variance ( σ 2 ). The ΔP of the next decade is projected to be within ±14.8% of the previous decades mean annual PRCPTOT over CA. The higher the RCPs, the higher the ΔP over CA. The results show that the detection and prediction of precipitation change will be challenging in arid CA.

Based on the standard method of dendrochronology, we examined the tree-ring width index of two dominant tree species in the Altay Mountains, China, including本研究以阿尔泰山富蕴地区的西伯利亚云杉和西伯利亚落叶松为对象,获取2个树种基部断面生长增量和树轮宽度年表与气候因子的相关系数,对比分析了相似生境下2个树种的径向生长特征及其对气候变化的响应。结果表明: 西伯利亚云杉基部断面生长增量总体高于西伯利亚落叶松,但西伯利亚落叶松的径向生长增加趋势更为显著。近60年来,上年快速生长期的高温对研究区内西伯利亚云杉的径向生长有限制作用,而当年6月较高的气温则有利于西伯利亚落叶松生长。西伯利亚落叶松的径向生长与当年1月气温呈负相关。分段相关分析显示,这种情况在1980年代中期气候变暖以后表现得更为明显。滑动相关分析表明,在气候变化背景下研究区内西伯利亚云杉和西伯利亚落叶松径向生长对气温和降水量的响应在近年来均有所增强。.

We constructed standard tree-ring-width chronology of使用零信号去趋势法建立了四川甘孜州拉日玛采点川西云杉标准化树轮宽度年表。结果表明: 云杉树轮年表与雅江3—8月一个月时间尺度的标准化降水蒸散指数(SPEI1)间存在显著正相关。由树轮年表当年与次年序列重建了雅江地区1442—2008年3—8月SPEI1指数变化,方差解释量达42.8%。重建序列主要揭示了历史时期SPEI1的低频变化。川西雅江地区3—8月SPEI1在过去567年中存在1442—1465年、1516—1601年和1836—2008年3个偏湿阶段,位于其间的为2个偏干阶段;重建序列在1455—1762年间存在显著变干趋势,而1833—1950年具有显著变湿趋势,1959—2008年的变湿趋势最为明显;3—8月SPEI1重建值在1512、1733、1767、1831、1941、1957和1975年发生了从干旱向湿润的突变,而在1684年与1961年则相反。与周边气候重建序列的对比显示,川西雅江地区3—8月SPEI1重建序列的低频变化与青藏高原东北部年降水量和祁连山东段北坡SPEI05指数的变化具有一定相似性。该重建序列对青藏高原东部及青海南部的3—8月SPEI1变化具有较好的代表性。.

Taking windfall woods of以伊犁南部山区雪岭云杉风倒木为对象,研究了1.3、5、10、15、20 m树高处树轮圆盘样品的最大密度、最小密度、早材平均密度、晚材平均密度4种树轮密度年表,结合当地气象观测资料进行相关分析,研究树干不同高度树轮密度对气候要素的响应特征。结果表明: 同一树高下4种密度参数在整体上表现出较高的相关性,其中10、15、20 m树高相对显著;不同树高处晚材平均密度的一致性相对较好;不同树高处树轮密度对气候要素的响应存在差异,15 m树高处最大密度、晚材平均密度对上年7—9月、当年5—9月平均气温具有较好的响应。因此,在1.3 m处采集雪岭云杉样本存在对气温响应估计偏低的可能。.

September–March mean temperature has been reconstructed to A.D. 1680 for the Kaiduhe River watershed on the southern slope of the Tien Shan Mountains, China, using the Picea schrenkiana tree-ring width. The reconstruction explains the variance of 47% in the observed mean temperature from 1953 to 2011. Power spectral and wavelet analyses demonstrated the existence of significant 50-year and 2- to 7-year cycles of variability. The results of the spatial correlations suggest that our reconstruction contains climatic signals for Central Asia. Warm periods occurred during 1696–1708, 1730–1748, 1784–1804, 1832–1855, 1892–1903, 1924–1928, 1937–1943, and 1987–2006; while the periods of 1685–1695, 1709–1729, 1749–1783, 1805–1831, 1856–1891, 1904–1923, 1929–1936, and 1944–1986 were relatively cold. The significant correlation coefficient between the reconstruction and the temperature reconstruction for the Urumqi River source reveals that the temperature variations in the annual cold period for the southern and the northern slope of the central Tien Shan Mountains are roughly synchronous over the last nearly 300 years. A comparison between the reconstruction and three winter North Atlantic Oscillation indexes revealed similar long-term trends.

The oxide-dispersion-strengthened (ODS) ferritic alloy powders (Fe-14Cr-3Al-2W-0.1Ti-0.35Y2O3) were prepared by mechanical alloying (MA) at a rotation speed of 720 rpm for 24 h. All the elements were mixed homogenously in the powder, and Cr and Al dissolved in α-Fe after MA. The bulk samples were produced by spark plasma sintering (SPS) at 950 and 50 MPa and by hot isostatic pressing (HIP) at 1150 and 130 MPa, respectively. The SPS sample showed a tensile strength of 730 MPa and a poor ductility due to the existence of pores in microsize. The HIP sample had a high tensile strength of 980 MPa, yield strength of 710 MPa and elongation of 10.3 %. The excellent mechanical properties of the HIP sample was due to the small grain size of the matrix of about 400 nm and the fine oxide particles of 5-40 nm.

July–June precipitation has been reconstructed back to A.D. 1464 for the Baluntai region on the southern slope of the central Tien Shan Mountains, China, using the Picea schrenkiana tree-ring width. The reconstruction explains the variance of 51% in the observed precipitation from 1959 to 2005. By employing a 21-year moving average to the reconstruction, nine periods with above average reconstructed precipitation comprised ∼1474–1503, 1550–1577, 1588–1619, 1658–1713, 1790–1812, 1833–1867, 1890–1907, 1923–1944, and 1988–1995∼; eight periods with below average reconstruction consisted of 1504–1549, 1578–1587, 1620–1657, 1714–1789, 1813–1832, 1868–1889, 1908–1922 and 1945–1987. The wet/dry periods of the reconstructed precipitation correspond well with other reconstructions. Some droughts in the historical documents are also precisely captured in the reconstruction. Precipitation variations for the southern slope of the central Tien Shan Mountains are roughly synchronous with that of the northern slope in the recent ∼300 year. Power spectral and wavelet analysis demonstrated the existence of significant ∼100-y, ∼60-y, ∼50-y, ∼16-y, ∼10-y and ∼2-y cycles of variability.

Profound hypercalcemia is usually due to underlying malignancy.We describe a case of granulomatous myositis presenting with extreme hypercalcemia of 20.1 mg/dl and generalized weakness that did not resolve despite rapid correction of serum calcium. The disease process was unmasked by cholecalciferol supplementation. Initial search for a malignant process yielded no diagnosis, but an elevated 1,25-dihydroxyvitamin D level, in the setting of a suppressed PTH and undetectable PTHrP, pointed to the presence of excessive 1α-hydroxylase activity.Biopsy of the vastus lateralis muscle showed extensive granulomatous myositis. Immunohistochemical staining for 1α-hydroxylase was localized to the multinucleated giant cells and histiocytes. Musculoskeletal magnetic resonance imaging showed involvement of proximal muscle groups of both thighs and upper limbs.Measurement of vitamin D metabolites is pivotal in diagnosing 1,25-dihydroxyvitamin D-mediated hypercalcemia. Granulomatous disease can occasionally cause profound hypercalcemia and needs to be considered in the differential diagnosis. 1,25-Dihydroxyvitamin D-mediated hypercalcemia is responsive to glucocorticoid therapy.

To investigate the role of tumor necrosis factor (TNF) alpha on the homing efficiency of hematopoietic stem/progenitor cells (HS/PC) into bone marrow and its mechanism.CFSE-labeled umbilical cord blood (UCB) CD34+ cells were transplanted into irradiated (control group) or combined with TNF alpha prepared (experimental group) BALB/c recipient mice. The distribution in peripheral blood, liver, lung and homing characteristics in bone marrow and spleen of UCB CD34+ cells, in BALB/c recipient mice were determined 20 hours after xenotransplantation by flow cytometry (FACS) and their homing efficiency was calculated. ELISA was used to measure serum SDF-1 alpha level. CXCR4 expression levels of on UCB CD34+ cells were assessed by FACS pre-/post-manipulation with TNF alpha. SDF-1 alpha expression level in bone marrow and spleen was tested by immunohistochemistry.UCB CD34+ cells mainly home into recipient mice bone marrow and spleen; The homing efficiency in experimental group bone marrow [(0.65 +/- 0.13)%] was significantly higher than that in control ones [(0.30 +/- 0.09)%, P0.01], whereas the homing efficiency in experimental group spleen was dramatically lower than that in control ones (P0.01); Treatment with TNF alpha did not affect recipient serum SDF-1 alpha level; After 18 hours co-cultured with TNF alpha, the CXCR4e expression level on UCB CD34+ cells was similar to that on fresh ones; TNF alpha treatment induced significantly higher SDF-1 alpha expression on osteoblastic and stromal cells in bone marrow, and reversed spleen SDF-1 alpha gradient that was originally favorable for CD34+ cells homing.TNF alpha enhances the homing efficiency of HS/PC via up-regulating SDF-1 alpha gradient in bone marrow, and might be an useful enhancer for HS/PC homing in clinical practice.