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The wide band gap, temperature stability, high resistivity, robustness of semiconducting boron carbide make it an attractive material for device applications.. Here the structural stability along with the electronic and the optical properties of Ni-doped boron carbides (B13C2) were studied using the first principle calculations based on plane wave pseudo-potential theory. The calculated results showed that Ni-doped in boron carbide was in preference to substituting C atom on the end of C-B-C chain, but it was difficult for Ni to substitute B atom in the center of the C-B-C chain or in the icosahedron. A representative stable structural unit containing Ni atom was [C-B-Nε+-[B11ε-, while the structural unit without Ni was [C-B-ε--[B12]ε+. The band structure, density of states (DOS) indicated that the coexistence of [C-B-Nε+-[B11ε-structural unit made electrical conductivity increased. Some new impurity energy levels appear in the band gap of Ni-doped B13C2, which can improve the conductivity of B13C2as well. Ni acts as an-type dopant. As the covalent bond of Ni-B was weaker than those of B-B and B-C, the thermal conductivity decreased for Ni-doped B13C2, thermoelectric property of Ni-doped boron carbides has been improved. The imaginary part of the dielectric function of Ni-doped B13C2has three remarkable peaks at 1.13, 3.89, and 6.05 eV. This reveals that doping with Ni can improve the photo-absorption efficiency of B13C2.

Structure stability and electronic properties of Cu-doped FeS2 were studied using the first principle calculations based on plane wave pseudo-potential theory. The calculated results revealed that the band-gap Eg of Cu-doped FeS2was 0.47 eV. The valence band of the density of state (DOS) was mostly due to the Cu 3d and S p orbitals. The bottom part of conduction band was mostly due to the Fe 3d orbitals. The calculated covalent character of the Fe–S bonds gave large delocalization of the spin resulting in smaller values. The Cu, Fe and S had the spin compensated leading to configuration s0.47 p0.61d9.78, Fe s0.27p0.58d7.03, S s1.83p4.23, respectively. The tetrahedral environment of the Fe and Cu and the relatively weak field of the S2− ligand were consistent to the Fe3+ and Cu+.

This paper establishes a density gradient model along the thickness direction of a circular plate made of foamed material. Based on the first shear deformation plate theory, the result is deduced that the foamed metal circular plate with graded density along thickness direction yields axisymmetric bending problem under the action of uniformly distributed load, and the analytical solution is obtained by solving the governing equation directly. The analyses on two constraint conditions of edge radial clamping and simply supported show that the density gradient index and external load may affect the axisymmetric bending behavior of the plate. Then, based on the classical plate theory, the paper analyzes the behavior of axisymmetric buckling under radial pressure applied on the circular plate. Shooting method is used to obtain the critical load, and the effects of gradient nature of material properties and boundary conditions on the critical load of the plate are analyzed.

Free vibration of thermal post-buckled functionally graded material (FGM) beams in a uniform electric field subjected to both temperature rise and voltage is studied. Voltage has a great influence on the deformation of the beam, and Thermo-electric post-buckling equilibrium paths and characteristic curves of the first three natural frequencies versus the temperature, the electricity and the material gradient parameters are plotted. It is found that the three lowest frequencies of the pre-buckled beam decrease with an increase in the temperature, but those of a buckled beam increase monotonically with the temperature rise. The results also show that the tensional force produced in the piezoelectric layers by the voltage can efficiently increase the critical buckling temperature and the natural frequency.

This paper studys on how the high degree mineral groundwater erodes the concrete building of great high lifts irrigation project in JingDian (GanSu province) and GuHai (NingXia province), and analyzes the break reasons for erosion and investigate the repair technique. In the idea of reducing the erosion medium and enhancing the concrete anti-erosion quality, the authors suggest a popularized repair technique and protection measure about the break reasons for erosion of the concrete building of high lifts water irrigation project in loess plateau regions.

A pot experiment was conducted to study the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone, and the combined stress on the growing process, stomatal resistance and leaf structure of green vegetable. The results showed that 1,2,4-TCB contamination alone had more significant inhibitory effect on the growth of green vegetable than the combined stress. Both UV-B radiation enhancement and 1,2,4-TCB contamination reduced the stomatal resistance of front and reverse leaves. Enhanced UV-B radiation resulted in the albino of leaves. 1,2,4-TCB contamination resulted in the fading of leaf color and the appearing of black spots on leaf surfaces, and the enhanced UV-B radiation strengthened the black-spot symptom. In conclusion, the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone and the combined stress on the growth indicators of green vegetable were different.

To improve the understanding of the clinical and laboratory features of the IgM multiple myeloma (MM).The clinical data of four cases of IgM MM patients were collected, their clinical and laboratory features were summarized and analyzed.Four patients met the criteria of IgM MM. They were all male. The age at the diagnosis ranged from 54 to 69 years. The primary symptoms included bone pain, hyperviscosity and bleeding. Three cases had κ-chain and only one case had λ-chain. They were all staged ⅢA according to the Durie-Salmon staging system (DSS). One case stagedⅠand three cases staged Ⅱ according to the international staging system (ISS). The average value of IgM, hemoglobin, serum calcium, creatinine and the proportion of bone marrow plasma cells were 83.6 (52.9-111.0) g/L, 79.5 (61.0-105.0) g/L, 3.20(2.11-6.00) mmol/L, 104.3 (56.0-171.0) μmol/L and 0.558 (0.290-0.775), respectively. Bone destruction was found in 3 cases. Immunophenotypes of bone marrow plasma cells were analyzed in 3 patients. Results showed that these cells expressed CD38 and CD138, and did not express CD19, CD20 and CD117. Chromosome and fluorescence in situ hybridization (FISH) analysis were carried out in 4 cases and found that all of them had IgH translocations and 1q21 amplification, 2 cases had 13q and 17p deletion, and 3 cases had t(11;14). Three patients received bortezomib-based regimens as induction therapy and reached partial response (PR) - very good partial response (VGPR). Followed up to November 30, 2012, the median progress-free survival (PFS) and overall survival (OS) of the 4 cases were only 6.0 (2.5-7.0) months and 17.5 (2.5-27.0) months, respectively.IgM MM is very rare and is no more than 0.5% in all types of MM. IgM MM have frequent t(11;14) and amp(1q21). Bortezomib-based regimens are effective for it, however, the disease progresses rapidly and has poor prognosis.目的 提高对IgM型多发性骨髓瘤（MM）患者临床及实验室特征的认识。方法 收集4例IgM型MM患者的临床资料，对其临床及实验室特征进行总结、分析。结果 4例患者符合IgM型MM的诊断。4例均为男性，年龄54~69岁，初发症状包括骨痛、高黏滞血症、出血，3例轻链为κ型，1例为λ型，Durie-Salmon（D-S）分期均为ⅢA期，国际分期系统（ISS）分期：Ⅰ期1例，Ⅱ期3例。平均IgM 83.6（52.9~111.0）g/L，HGB 79.5（61.0~105.0）g/L，血钙3.20（2.11~6.00）mmol/L，肌酐104.3（56.0~171.0）μmol/L，骨髓浆细胞比例0.558（0.290~0.775），3例存在骨质破坏。3例患者行免疫表型检测均表达CD38、CD138，不表达CD19、CD20、CD117。染色体、荧光原位杂交检查结果显示4例患者均有IgH易位和1q21扩增，2例伴有13q和17p缺失，3例明确为t(11;14)。3例予以硼替佐米为主的方案诱导化疗，达到部分反应至非常好的部分反应。随访至2012年11月30日，无进展生存时间仅6.0（2.5~7.0）个月，总生存时间仅为17.5（2.5~27.0）个月。结论 IgM型MM非常罕见，在所有类型MM患者中不到0.5%，细胞遗传学异常以t(11;14)和1q21阳性多见，硼替佐米为主的方案治疗有效，但患者病情进展迅速，总体预后较差。

To evaluate the efficacy and safety of bortezomib retreatment in 76 patients with relapsed/refractory multiple myeloma (MM), who previously responded to bortezomib.Retrospective analysis of 76 MM patients, who had achieved at least a partial response (PR) on initial bortezomib therapy in our hospital from May 2006 to August 2011, received bortezomib retreatment when they relapsed or progressed.The overall response rate (ORR) was 60.5%, among them 6.5% patients achieved CR, 5.8% patients achieved very good partial response (VGPR), 38.2% patients achieved PR. Then we further stratified all patients into 3 groups according to the response of initial bortezomib therapy, including CR group, VGPR group and PR group. After bortezomib retreatment, the ORR of the 3 groups was 84.6%, 73.1% and 43.2%, respectively. According to the response of bortezomib retreatment, the patients were divided into 2 groups: group 1 who at least achieved PR, group 2 who showed no response. The median progression-free survival (PFS) after bortezomib retreatment for group 1 and 2 was 7(1-39) and 5(1-14) months, respectively (P0.05), while the median overall survival (OS) after bortezomib retreatment was 16(2-64) and 8(1-28) months, respectively (P0.05). Adverse events (AE) were identified in 88% patients during bortezomib retreatment, including neutropenia, diarrhea and thrombocytopenia, only 9.2%(7 patients) reached Ⅲ-Ⅳ grade of AE. Severe peripheral neuropathy occurred in only one patient.Bortezomib retreatment regimen is demonstrated a higher response rate in patients who achieved deeper response in initial treatment, with no more adverse events.目的 探讨硼替佐米再治疗多发性骨髓瘤（MM）的疗效及安全性。方法 回顾性分析2006年5月至2011年8月收治的76例硼替佐米初次治疗疗效达部分反应（PR）以上，复发或疾病进展后予以硼替佐米再治疗的MM患者，评价硼替佐米再治疗的疗效及不良反应。结果 硼替佐米再治疗MM的总有效率（ORR）为60.5%，其中完全反应（CR）率 6.5%，非常好的部分反应（VGPR）率15.8%，PR率38.2%。按硼替佐米初治后疗效分为CR、VGPR、PR组，3组患者再治疗后ORR分别为84.6%、73.1%和43.2%。按患者硼替佐米再治疗后疗效分成2组，达到PR及以上的为有效组，未达到PR的为无效组，两组自硼替佐米再治疗后中位疾病无进展生存期分别为7（1~39）个月和5（1~14）个月（P0.05）；中位总生存期分别为16（2~64）个月和8（1~28）个月（P0.05）。88.2%的患者硼替佐米再治疗时出现不同程度的不良反应，其中仅9.2%（7例）患者为Ⅲ~Ⅳ级，主要为中性粒细胞减少、腹泻和血小板减少，仅1例发生严重的周围神经病变。结论 硼替佐米初治疗效好的MM患者，再予以硼替佐米治疗反应率高，不良反应发生率较前无明显增加。

To evaluate the efficacy and safety of dose-reduced intravenous busulfan, cyclophosphamide and etoposide (BCV) as conditioning for autologous stem cell transplantation (ASCT) in multiple myeloma (MM).From September 2007 to September 2010, thirty-two ASCT-eligible patients with MM received high dose melphalan (HDM) as conditioning in our center. Median age was 53.5 (30-63) years. From October 2010 to October 2012, thirty-eight patients conditioned by BCV regimen (intravenous busulfan, total doses 9.6 mg/kg), whose median age was 54(35-64) years.There were no statistical differences in clinical characteristics between the two groups, including myeloma isotype, Durie-Salmon staging, international staging system(ISS), and patients received the first line, second line or more than third line therapy. The median time to neutrophil and platelet engraftment were 10.5 vs 11 days (P=0.057) and 11 vs 12 days (P=0.100) in the BCV and HDM groups, respectively. The toxicity of two conditioning regimens had no significant difference. None of hepatic veno-occlusive disease and early transplant related mortality was observed. Although overall response rates showed no significant difference between two groups (P0.05), the CR rates increased from 44.74% pre-ASCT to 63.18% post-ASCT in the BCV group, while 37.50% to 59.38% in the HDM group. During the median follow-up of 16 months (range 2-27) in BCV group, ten patients (26.32%) developed progressive disease and PFS at 12 months were 71.37%.In this study, the dose-reduced intravenous busulfan, cyclophosphamide and etoposide (BCV) conditioning was demonstrated an effective and safety regimen for ASCT-eligible patients with MM. However, the long term observation is needed.目的 评价BCV（白消安+环磷酰胺+足叶乙甙）预处理方案在多发性骨髓瘤（MM）自体造血干细胞移植（ASCT）患者的疗效和安全性。方法 2007年9月至2010年9月采用大剂量马法兰对32例MM患者行ASCT预处理（HDM组），中位年龄53.5（30~63）岁；2010年10月至2012年10月采用BCV方案（白消安静脉给药、总剂量9.6 mg/kg）对38例MM患者行ASCT预处理（BCV组），中位年龄54（35~64）岁。结果 两组患者MM分型、Durie-Salmon分期、国际分期体系(ISS)分期及接受一、二、三线以上治疗患者比例差异均无统计学意义。BCV组与HDM组比较，中性粒细胞植入时间[10.5（9~15）d对11（9~27）d，P=0.057]和血小板植入时间[11（9~210）d对12（10~45），P=0.100]，差异均无统计学意义。两组患者预处理不良反应相似，无肝静脉阻塞病和移植早期死亡发生。BCV组、HDM组患者ASCT后完全缓解率（分别为63.18%、59.38%）均高于ASCT前（分别为44.74%、37.50%）。BCV组中位随访16（2~27）个月，10例（26.32%）患者出现疾病进展，1年无进展生存率为71.37%。结论 含减低剂量白消安针剂的BCV方案对于MM患者是安全、有效的ASCT预处理方案，其远期疗效尚待长期随访观察。

To explore the value of conventional cytogenetic technique (CC), modified cell culture (long term culture and increasing the final concentration of colcemid) and fluorescence in situ hybridization (FISH) in detection of chromosomal and genomic aberrations of multiple myeloma(MM).RHG banding was used to evaluate the efficiency of modified culture method on abnormal karyotype detection in 21 MM patients. The probes 1q21, 13q14 (RB1), 14q32 (IGHC/IGHV gene) were used to perform FISH in the detection of chromosomal and genomic aberrations of MM.Abnormal chromosomes were detected in 4 cases (19.1%) of the 21 MM patients with CC. After modified cell culture, abnormal karyotype was detected in 6 cases (28.6%). Abnormal chromosomes were detected in 12 of 18 cases (66.7%) using FISH. Panel FISH disclosed 1q21 amplification in 4 (22.2%), del(13q) abnormality in 5 (27.8%), 14q32 rearrangement in 8 (44.4%).FISH can significantly improve the detection rate of chromosomal aberrations in MM.