In search of tuberculosis virulence genes

The identity of the virulence genes that enable tuberculosis organisms to survive in macrophages and to induce the features of tuberculosis remains largely unknown. Numerous putative virulence genes have been identified, but so far there is only conclusive evidence for the role of two genes, KatG and rpoV, in virulence.     

HLA-DR mismatching correlates with early cardiac allograft rejection, incidence, and graft survival when high-confidence-level serological DR typing is used

To determine if cardiac allograft outcome is improved among patients with fewer HLA-DR mismatches with their donors, we studied 132 recipients of a primary cardiac allograft who were transplanted between December 1985 and December 1991. These recipients and their donors all had high-confidence-level serological HLA-DR typing, previously shown to correlate highly with DNA DR typing. Patients were divided in two groups based on the HLA-DR mismatch with their donors. Group I consisted of 78 patients with 1 or zero DR mismatch and group II of 54 patients with 2 DR mismatches. Allograft outcome measurements included incidence of moderate rejection, incidence of allograft vasculopathy at 12 months, cardiac function measured as left ventricular ejection fraction (LVEF) and cardiac index (CI), and actuarial graft survival up to 7 years. Groups I and group II were not different with regard to recipient age, donor age, ischemia time, pulmonary vascular resistance, sex, or PRA greater than 0%. Group II had a higher incidence of moderate rejection on the first-week biopsy (47% vs. 25%, P = 0.019), and during the first month (84% vs. 58%, P = 0.006), but no difference was found in frequency of rejection from months 2 to 12. LVEF was not different in the groups at any point. CI was better in group I at 12 months (2.76 vs. 2.5, P = 0.03). No statistically significant difference was found in incidence of allograft vasculopathy (17% vs. 26%, P = 0.204). Actual graft survival at 1 year was better for group I (91% vs. 74%, P = 0.008), and actuarial graft survival at 6 years also favored group I (76% vs. 56%, P = 0.04). Using high-confidence-level serological HLA-DR typing assignments we demonstrated that HLA-DR mismatching correlates highly with cardiac allograft outcome. Implications are that heart transplant survival could be improved if prospective matching were feasible and prioritized or if immunosuppression were tailored to the HLA-DR match.     

钠冷快堆中喷雾钠火的计算分析

根据钠冷快堆中喷雾钠火的特点建立了理论模型，编制了SSPRAY程序。该程序模拟钠喷雾燃料过程中钠滴的运动、钠和氧气的燃烧反应、热量传递和质量传递等瞬态过程。用该程序计算了气体和墙壁温度、气体压力、氧气摩尔份额、喷雾流燃烧速率和热量热递速率等主要参数。利用AI实验数据和美国SPRAY－3A的计算结果对程序进行了验证，结果符合较好。     

电沉积Ni-W合金镀层的X射线光电子能谱分析

采用X射线光电子能谱（XPS）对电沉积Ni-W合金镀层表面膜进行了分析。研究结果表明，Ni-W合金镀层表面存在一层薄的氧化膜，而钨的氧化作用远大于镍，Ni-W合金镀层中W含量的提高对耐蚀性起决定作用。     

Creating and Justifying Research and Development Value: Scope,Scale, Skill and Social Networking of R&D

In this paper we describe a framework for analysing the creation and justification of Research & Development. The 4S framework is developed for analysing the scope, scale, skills and social network aspects of Research & Development value. The framework is based on social system theory, a process contingency model, and recent Research & Development metrics. We present a first empirical assessment based on a workshop using the 4S framework for leveraging Research & Development. Results that assist in the assessment of value creation utilising R & D within networks are very relevant in high tech industries. The multi–dimensional process approach of this framework seems promising for understanding and managing R&D value creation, but needs further operationalisation. Case studies are described and a Dutch network on leveraging R&D has been initiated.     

Fetal lung growth after tracheal ligation is not solely a pressure phenomenon

We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE. Thus, the age-dependent and coordinate diminution in cell proliferative activity and cell death events may serve to maintain the thickness of the OE as mice mature and age.     

Qualitative approach: a contribution to nursing

This paper focus on some characteristics of the qualitative methodology. Some of these methods are explored such as: participatory research, phenomenology, grounded theory and ethnography critical theory Perspectives of their utilization in nursing research are examined.