~(93)Pd的β缓发质子衰变

通过58 Ni(40 Ca ,3n2p)反应合成等待点核93 Pd ,采用氦喷嘴带传输系统加p γ符合 ,观测到了它的 β缓发质子衰变 ,测得其半衰期为 (1.3± 0 .2 )s .采用统计模型计算拟合了实验测得的 β缓发质子能谱和布居到质子发射体子核不同终态的分支比 ,指认了93 Pd的基态自旋为 9 2 .用Woods XasonStrutinsky方法计算了93 Pd的核位能面 ,其结果表明93 Pd基态自旋宇称可能为 9 2 + .

~(19)F+~(93)Nb耗散反应的相互作用时间

测量了1 9F + 93Nb耗散反应产物的激发函数与角分布 .从角分布的斜率提取的该反应系统的平均寿命在对称性较大的入射系统中反映了系统中耗散产物的特征时间 ;通过能量自关联函数方法从激发函数提取的反应时间不论在对称的还是在非对称的入射系统中都反映了耗散产物的特征时间 .能量自关联函数还可以给出双核系统的转动角速度以及表征转动阻尼的退相干宽度 ,更好地描述双核系统随时间的整个演化过程 .

~(19)F+~(93)Nb耗散反应产物激发函数中截面测量的不重复性

完成了 1 9F + 93Nb重离子耗散碰撞激发函数的两次独立测量 .束流的入射能量为 1 0 0— 1 0 8MeV ,步长 2 50keV .两次测量的宏观条件几乎完全一样 ,惟一的差别是使用了厚度分别为 70和 71 μg cm2 的两块 93Nb同位素靶 .实验结果表明 :( 1 )两次测量所得到的耗散反应产物激发函数的涨落具有不可平滑的结构 ;( 2 )这种不平滑的涨落截面有不重复的迹象 .着重从实验的角度对这一结果进行了讨论 .

~(19)F+~(93)Nb重离子耗散碰撞中截面测量的不可重复性(英文)

完成了１９Ｆ＋９３Ｎｂ重离子耗散碰撞激发函数的两次独立测量．束流１９Ｆ８＋的入射能量１００—１０８ＭｅＶ，能量步长２５０ｋｅＶ；两次测量中分别使用了厚度为７０和７１μｇ／ｃｍ２的９３Ｎｂ靶，其它宏观实验条件（例如，入射能量及能量步长，探测器及其探测角度，加速器、电子学以及数据获取系统的参数选取等等）则保持完全相同．实验结果表明，两次测量所得到的耗散产物截面的激发函数的不平滑结构具有不可重复性．这一实验结果支持了最近提出的理论预言：“在复杂量子碰撞中存在对初始条件的极端敏感性与混沌运动．”

真鲷（Pagrus major）胚胎超低温损伤机理研究

鱼类胚胎由于其自身结构特征：体积大、含水量高、多室结构等，迄今超低温保存尚未成功。超低温保存过程中所造成的冷冻损伤是制约鱼类胚胎超低温保存成功与否的关键，具体表现为渗透压影响、抗冻剂毒性、冰晶损伤等。系统研究并阐明鱼类胚胎冷冻损伤机理，是成功建立鱼类胚胎超低温保存技术的基础。本论文主要针对胚胎对渗透压的耐受性、抗冻剂对胚胎的渗透性、降温速率对胚胎内外冰晶形成温度的影响等冷冻损伤机理进行了系统研究，主要研究结果如下： 1.通过检测胚胎在不同浓度人工海水（0%、25%、50%、75%、1×、2×、3×、4×，渗透压范围0~3740 mOsm/kg）中的孵化率，确定了真鲷不同发育时期胚胎对渗透压的耐受范围，以及心跳期胚胎浸泡不同时间对渗透压的耐受范围。结果显示：①真鲷2-4细胞期、原肠期、10-14体节期胚胎、心跳期和出膜前期胚胎孵化率>50%时渗透压的范围依次为：919~1391 mOsm/kg、919~1391 mOsm/kg、462 ~1391 mOsm/kg、232~1878 mOsm/kg和692~1391 mOsm/kg，表明心跳期胚胎对渗透压变化的耐受范围最广；②在不同浓度人工海水中分别浸泡10 min、30 min、1 h、5 h和10 h后，真鲷胚胎孵化率无显著变化的渗透压范围分别为0~2804 mOsm/kg、0~1878 mOsm/kg、232~1391 mOsm/kg、232~1391 mOsm/kg和919~1391 mOsm/kg；结果表明心跳期胚胎对渗透压的耐受范围随浸泡时间的延长而减小。 2.采用毛细管电泳技术检测胚胎内部DMSO的浓度，并且分析了胚胎孵化率和胚胎内部DMSO的浓度随浸泡时间变化与外部抗冻剂的关系。结果表明胚胎孵化率随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而降低；胚胎内部DMSO浓度随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而增加。对胚胎孵化率（y1）随抗冻剂溶液浓度（x）的变化进行一元三次多项式回归，当浸泡时间分别为10 min、30 min和60 min时，回归方程依次为：y1 = -2832.7x3 + 575.01x2 - 37.011x + 99.641（R2 = 0.9722）；y1 = 30288x3 - 16322x2 + 2077.3x + 27.603（R2 = 0.9876）；y1 = 16052x3 - 5985.2x2 - 32.696x + 119.6（R2 = 0.9124）。对胚胎内部DMSO浓度（y2）随抗冻剂溶液浓度（x）的变化进行回归，当浸泡时间分别为10 min、30 min和60 min时，回归方程依次为：y2 = 0.2584e6.7294x（R2 = 0.9876）；y2 = 0.2521e10.964x（R2 = 0.9644）；y2 = 0.4054e10.95x（R2 = 0.8954）。 3. 利用低温显微镜观察了不同降温速率（20、40、60、80、100、120℃/min）对胚胎内外冰晶形成温度的影响。胚胎外部冰晶形成温度（TEIF）随降温速率的增加显著下降，在降温速率大于80℃/min之后，TEIF随降温速率增加而降低的幅度减小；胚胎内部冰晶形成温度（TIIF）在降温速率小于80℃/min 时随降温速率的升高而降低，在降温速率大于80℃/min 时随降温速率的升高而升高；胚胎内外冰晶形成温度差值（TEIF - TIIF）在降温速率小于80℃/min时随降温速率的升高而增大，在降温速率大于80℃/min时随降温速率的升高而减小。 4. 在低温显微镜下观察了真鲷胚胎低温保存中有复活胚胎记录的保存方法在冷冻解冻过程中的冰晶形成过程，结果表明：①在冷冻过程中，玻璃化法冷冻的胚胎的内部冰晶形成温度（-53.70，-64.33℃）显著低于程序降温法（-17.51，-21.40℃）；而且在玻璃化法冷冻的胚胎内部冰晶形成温度高于外部冰晶后形成（-70.30℃），程序降温法中则相反，胚胎内部冰晶形成温度显著低于外部冰晶形成温度（-4.93，-5.00℃）；玻璃化法中，40%PG冷冻的胚胎外部溶液出现玻璃化现象，其他组均未出现；②在解冻过程中，各组均出现重结晶现象；解冻后，玻璃化法的胚胎完整率（62.82%）远高于程序降温法（9.21%）。

The transformation of Ireland 1958 - 93: the role of ideas in punctuating institutional path dependency at critical junctures

Ireland experienced two critical junctures when its economic survival was threatened: 1958/9 and 1986/7. Common to both crises was the supplanting of long established practices, that had become an integral part of the political culture of the state, by new ideas that ensured eventual economic recovery. In their adoption and implementation these ideas also fundamentally changed the institutions of state – how politics was done, how it was organised and regulated. The end result was the transformation of the Irish state. The main hypothesis of this thesis is that at those critical junctures the political and administrative elites who enabled economic recovery were not just making pragmatic decisions, their actions were influenced by ideas. Systematic content analysis of the published works of the main ideational actors, together with primary interviews with those actors still alive, reveals how their ideas were formed, what influenced them, and how they set about implementing their ideas. As the hypothesis assumes institutional change over time historical institutionalism serves as the theoretical framework. Central to this theory is the idea that choices made when a policy is being initiated or an institution formed will have a continuing influence long into the future. Institutions of state become ‘path dependent’ and impervious to change – the forces of inertia take over. That path dependency is broken at critical junctures. At those moments ideas play a major role as they offer a set of ready-made solutions. Historical institutionalism serves as a robust framework for proving that in the transformation of Ireland the role of ideas in punctuating institutional path dependency at critical junctures was central.

La migración de cultivos de granos como indicador del cambio climático 1941 - 93 en la región pampeana argentina

p.171-176

Nomenclature and syntaxonomic notes on some high-rank syntaxa of the European grassland vegetation

We present descriptions of a new order (Ranunculo cortusifolii-Geranietalia reuteri and of a new alliance (Stachyo lusitanicae-Cheirolophion sempervirentis) for the herbaceous fringe communities of Macaronesia and of the southwestern Iberian Peninsula, respectively. A new alliance, the Polygalo mediterraneae-Bromion erecti (mesophilous post-cultural grasslands), was introduced for the Peninsular Italy. We further validate and typify the Armerietalia rumelicae (perennial grasslands supported by nutrient-poor on siliceous bedrocks at altitudes characterized by the submediterranean climate of central-southern Balkan Peninsula), the Securigero-Dasypyrion villosae (lawn and fallow-land tall-grass annual vegetation of Italy), and the Cirsio vallis-demoni-Nardion (acidophilous grasslands on siliceous substrates of the Southern Italy). Nomenclatural issues (validity, legitimacy, synonymy, formal corrections) have been discussed and clarified for the following names: Brachypodio-Brometalia, Bromo pannonici-Festucion csikhegyensis, Corynephoro-Plantaginion radicatae, Heleochloion, Hieracio-Plantaginion radicatae, Nardetea strictae, Nardetalia strictae, Nardo-Callunetea, Nardo-Galion saxatilis, Oligo-Bromion, Paspalo-Heleochloetalia, Plantagini-Corynephorion and Scorzoneret alia villosae. 

Is screening for Factor V Leiden and Prothrombin G20210A Mutations in Renal Transplantation worthwhile? Results of a large single-center U.K. study

This single center study is the largest series of renal transplant recipients and donors screened for the commonest prothrombotic genotypes. A total of 562 transplant recipients and 457 kidney donors were genotyped for the factor V Leiden and prothrombin G20210A mutations. The prevalence of heterozygous factor V Leiden was 3.4% and 2.6% and prothrombin G20210A was 2.0% and 1.1% in recipients and donors, respectively, similar frequencies to that of the general U.K. population. The 30-day and 1-year graft survival rates in recipients with thrombophilic mutations were 93% and 93%, compared with 88% and 82% in patients without these mutations (log-rank P =0.34). Thrombophilia in recipients (odds ratio 0.55; confidence interval 0.06-2.29; P =0.56) or in donors (odds ratio 1.53; confidence interval 0.27-5.74; P =0.46) did not correlate with graft loss at 30 days after transplantation. In contrast to recent reports, this study did not demonstrate an association between thrombophilia and renal allograft loss, and routine screening is not recommended.

Changes in functional behavior of 93 % Pb(Mg1/3Nb2/3)O-3-7 % PbTiO3 thin films induced by ac electric fields

The dielectric properties of Au/[93%Pb(Mg1/3Nb2/3)O-3-7%PbTiO3] (PMN-PT)/(La0.5Sr0.5)CoO3/MgO thin-film capacitor heterostructures, made using pulsed laser deposition, have been investigated, with particular emphasis on the changes in response associated with increasing the magnitude of the ac measuring field. It was found that increasing the ac field caused a change in the frequency spectrum of relaxators, increasing the speed of response of "slow" relaxators, with an associated decrease in the freezing temperature (T-f) of the relaxor system; in addition, other characteristic parameters relating to polar relaxation (activation energy E-a and attempt frequency 1/tau(0)), described by fitting of the dielectric response to a Vogel-Fulcher expression, were found to change continuously as ac field levels were increased.

Annotation of Case C-43/93, Raymond Vander Elst v Office des Migrations Internationales, ECR I-3803

Freedom to provide services - Nationals of a non-member country - Posted Workers

Annotation of Case C-375/92, Commission v Kingdom of Spain, ECR 1994 I-923, and Case C-45/93, Commission v Kingdom of Spain, ECR 1994 I-911

Failure to fulfil obligations - Freedom to provide services - Tourist guides - Professional qualification required by national rule - Discrimination - Museum admission