47 MeV/u ~(12)C与~(133)Cs反应中碘同位素产生截面的Q_(gg)依赖关系

用47 MeV/u 12C离子轰击133Cs靶,应用放射化学分离技术和离线γ射线谱学,得到碘同位素的产生截面。丰中子碘同位素的独立产生截面指数地依赖于Qgg值,而缺中子碘同位素的独立产生截面则偏离这一直线关系。这一事实可对在深部非弹转移过程中产生丰中子碘同位素予以解释。

Adaptive hormetic response of pre-exposure of mouse brain with low-dose C-12(6+) ion or Co-60 gamma-ray on growth hormone (GH) and body weight induced by subsequent high-dose irradiation

The brain of the Kun-Ming strain mice were irradiated with 0.05 Gy of C-12(6+) ion or Co-60 gamma-ray as the pre-exposure dose, and were then irradiated with 2 Gy of 12C6+ ion or Co-60 gamma-ray as challenging irradiation dose at 4 h after per-exposure. Body weight and serum growth hormone (GH) concentration were measured at 35th day after irradiation. The results showed that irradiation of mouse brain with 2 Gy of C-12(6+) ion or Co-60 gamma-ray significantly diminished mouse body weight and level of serum GH. The relative biological effectiveness values of a 2 Gy dose of C-12(6+) ion calculated with respect to Co-60 gamma-ray were 1.47 and 1.34 for body weight and serum GH concentration, respectively. Pre-exposure with a low-dose (0.05 Gy) of C-12(6+) ion or Co-60 gamma-ray significantly alleviated reductions of mouse body weight and level of serum GH induced by a subsequent high-dose (2 Gy) irradiation. The data suggested that low-dose ionizing irradiation can induce adaptive hormetic responses to the harmful effects of pituitary by subsequent high-dose exposure.

Germ cell loss induced by C-12(6+) ion irradiation in young female mice

The ovaries of Kun-Ming strain mice (3 weeks) were irradiated with different doses of C-12(6+) ion in the Bragg peak or the plateau region. At 10th day after irradiation, ovarian and uterine weights were measured: normal and atretic (identified with the oocyte to be degenerating or absent) primordial, primary and preantral follicles were identified in the largest cross-section of each ovary. Percentage (%) of normal follicles of each developmental stage of oogenesis was calculated. The data showed that compared to controls, there was a dose-related decrease in percentage of normal follicles in each developmental stage. And the weights of ovary and uterus were also reduced with doses of irradiation. Moreover, these effects were much more significant in the Bragg peak region and the region close to the Bragg peak than in the beam's entrance (the plateau region). Radiosensitivity varied in different follicle maturation stages. Primordial follicles, which are thought to be extremely sensitive to ionizing irradiation, were reduced by 86.6%, while primary and preantral follicles reduced only by 72.5% and 61.8% respectively, by exposure with 6 Gy of C-12(6+) ion in the Bragg peak region and the region close to the Bragg peak. The data suggested that due to their optimal depth-dose distribution in the Bragg peak region, heavy ions are ones of the best particles for radiotherapy of tumors located next of vital organs or/and surrounded by normal tissues, especially radiosensitive tissues such as gonads.

Systematic study of the transfer of amino acids across the water/1,2-dichloroethane interface facilitated by dibenzo-18-crown-6

Facilitated ion transfer reactions of 20 amino acids with di.benzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, Ile, Phe, Trp, Met, Ala, Gly, Cys, Gln (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (beta(0)), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization.

聚氯乙烯-尼龙6树脂分离富集碘量法测定金精矿中金

采用聚氯乙烯尼龙６树脂分离富集溶解于王水中的金精矿样品中的金，然后用乙二胺溶液洗脱，并用碘量法测金。经标样验证，结果令人满意。

红原泥炭纤维素氧同位素指示的距今6 ka温度变化

红原泥炭氧同位素指示的近6000年温度变化，其总体趋势与金川温度变化，敦德温度变化一致，与格陵兰冰芯记录的温度变化趋势也相似。具体的气候事件具有明显的全球一致性。最近6000年温度变化存在两个明显的“转折点”，既4000a BP左右气温由低温变为高温，1500a BP左右气温由高温变为低温。功率谱分析发现红原泥炭氧同位素序列包含1220~1087a、752a、444a、325a、213a、127-123a、88a、79a这样的周期。分析表明红原地区气候驱动因子可能主要是太阳活动，同时海洋活动信号也通过海气

The pyrrolo-1,5-benzoxazepine, PBOX-6, inhibits the growth of breast cancer cells in vitro independent of estrogen receptor status and inhibits breast tumour growth in vivo

Members of a novel series of pyrrolo-1,5-benzoxazepine (PBOX) compounds have been shown to induce apoptosis in a number of human leukemia cell lines of different haematological lineage, suggesting their potential as anti-cancer agents. In this study, we sought to determine if PBOX-6, a well characterised member of the PBOX series of compounds, is also an effective inhibitor of breast cancer growth. Two estrogen receptor (ER)-positive (MCF-7 and T-47-D) and two ER-negative (MDA-MB-231 and SK-BR-3) cell lines were examined. The 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to determine reduction in cell viability. PBOX-6 reduced the cell viability of all four cell lines tested, regardless of ER status, with IC(50) values ranging from 1.0 to 2.3 microM. PBOX-6 was most effective in the SK-BR-3 cells, which express high endogenous levels of the HER-2 oncogene. Overexpression of the HER-2 oncogene has been associated with aggressive disease and resistance to chemotherapy. The mechanism of PBOX-6-induced cell death was due to apoptosis, as indicated by the increased proportion of cells in the pre-G1 peak and poly(ADP-ribose) polymerase (PARP) cleavage. Moreover, intratumoural administration of PBOX-6 (7.5 mg/kg) significantly inhibited tumour growth in vivo in a mouse mammary carcinoma model (p=0.04, n=5, Student's t-test). Thus, PBOX-6 could be a promising anti-cancer agent for both hormone-dependent and -independent breast cancers.

Cahier contenant des notes, en turc, en persan, en arabe, dont les plus importantes sont (folio 6 verso) des fetvas relatifs aux biens de main-morte de Sainte-Sophie, et le commencement d'un traité d'Insha (folio 35 verso).

Ravius (Christiani Ravij Berlinatis) ; Thévenot.

Informe de seguimiento No. 6 Construcción Troncales de Transmilenio Fase III

Gestión del conocimiento

Certificate that Joseph Kingsmill, sheriff, has sold 6 acres in Lot no. 9 in the 4th Concession of Caistor to W.H. Dickson [originally said S.D. Woodruff, but this was crossed out]

Certificate that Joseph Kingsmill, sheriff, has sold 6 acres in Lot no. 9 in the 4th Concession of Caistor to W.H. Dickson [originally said S.D. Woodruff, but this was crossed out], May 23, 1857.

L'Action universitaire – vol. 2, no 6, mai 1936

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