Texture, twinning and metastable "tetragonal" phase in ultrathin films of HfO₂ on a Si substrate

Thin HfO<sub>2</sub> films grown on the lightly oxidised surface of (100) Si wafers have been examined using dark-field transmission electron microscopy and selected area electron diffraction in plan view. The polycrystalline film has a grain size of the order of 100 nm and many of the grains show evidence of twinning on (110) and (001) planes. Diffraction studies showed that the film had a strong [110] out-of-plane texture, and that a tiny volume fraction of a metastable (possibly tetragonal) phase was retained. The reasons for the texture, twinning and the retention of the metastable phase are discussed

Contribution of recent transgenic models and transcriptional profiling studies to our understanding of the mechanisms by which androgens control spermatogenesis

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Selective Ablation of the Androgen Receptor in Mouse Sertoli Cells Affects Sertoli Cell Maturation, Barrier Formation and Cytoskeletal Development

The observation that mice with a selective ablation of the androgen receptor (AR) in Sertoli cells (SC) (SCARKO mice) display a complete block in meiosis supports the contention that SC play a pivotal role in the control of germ cell development by androgens. To delineate the physiological and molecular mechanism responsible for this control, we compared tubular development in pubertal SCARKO mice and littermate controls. Particular attention was paid to differences in SC maturation, SC barrier formation and cytoskeletal organization and to the molecular mediators potentially involved. Functional analysis of SC barrier development by hypertonic perfusion and lanthanum permeation techniques and immunohistochemical analysis of junction formation showed that SCARKO mice still attempt to produce a barrier separating basal and adluminal compartment but that barrier formation is delayed and defective. Defective barrier formation was accompanied by disturbances in SC nuclear maturation (immature shape, absence of prominent, tripartite nucleoli) and SC polarization (aberrant positioning of SC nuclei and cytoskeletal elements such as vimentin). Quantitative RT-PCR was used to study the transcript levels of genes potentially related to the described phenomena between day 8 and 35. Differences in the expression of SC genes known to play a role in junction formation could be shown from day 8 for Cldn11, from day 15 for Cldn3 and Espn, from day 20 for Cdh2 and Jam3 and from day 35 for ZO-1. Marked differences were also noted in the transcript levels of several genes that are also related to cell adhesion and cytoskeletal dynamics but that have not yet been studied in SC (Actn3, Ank3, Anxa9, Scin, Emb, Mpzl2). It is concluded that absence of a functional AR in SC impedes the remodeling of testicular tubules expected at the onset of spermatogenesis and interferes with the creation of the specific environment needed for germ cell development

A test-proven As-grown-Generation (A-G) model for predicting NBTI under use-bias

For the first time, we demonstrate that A-G model extracted from short Vg-accelerated stresses can predict both long term DC and AC NBTI under low and dynamic operation Vg. This is achieved by successfully separating non-saturating defects from the saturating ones, allowing reliable extraction of power exponents needed for long term prediction. Unlike R-D model, A-G model does not require solving differential equations for AC NBTI. This saves computation time significantly, especially for high-frequency that needs small time-step, and makes it readily implementable in SPICE-like simulators

Policies to improve end-of-life decisions in Flemish hospitals: communication, training of health care providers and use of quality assessments

<p>Abstract</p> <p>Background</p> <p>The prevalence and implementation of institutional end-of-life policies has been comprehensively studied in Flanders, Belgium, a country where euthanasia was legalised in 2002. Developing end-of-life policies in hospitals is a first step towards improving the quality of medical decision-making at the end-of-life. Implementation of policies through quality assessments, communication and the training and education of health care providers is equally important in improving actual end-of-life practice. The aim of the present study is to report on the existence and nature of end-of-life policy implementation activities in Flemish acute hospitals.</p> <p>Methods</p> <p>A cross-sectional mail survey was sent to all acute hospitals (67 main campuses) in Flanders (Belgium). The questionnaire asked about hospital characteristics, the prevalence of policies on five types of end-of-life decisions: euthanasia, palliative sedation, alleviation of symptoms with possible life-shortening effect, do-not-resuscitate decision, and withdrawing or withholding of treatment, the internal and external communication of these policies, training and education on aspects of end-of-life care, and quality assessments of end-of-life care on patient and family level.</p> <p>Results</p> <p>The response rate was 55%. Results show that in 2007 written policies on most types of end-of-life decisions were widespread in acute hospitals (euthanasia: 97%, do-not-resuscitate decisions: 98%, palliative sedation: 79%). While standard communication of these policies to health care providers was between 71% and 91%, it was much lower to patients and/or family (between 17% and 50%). More than 60% of institutions trained and educated their caregivers in different aspects on end-of-life care. Assessment of the quality of these different aspects at patient and family level occurred in 25% to 61% of these hospitals.</p> <p>Conclusions</p> <p>Most Flemish acute hospitals have developed a policy on end-of-life practices. However, communication, training and the education of health care providers about these policies is not always provided, and quality assessment tools are used in less than half of the hospitals.</p

Postcolonial manifestations of African spatiality in Europe : the invisible 'public' spaces of Ghent

The focus of this chapter is on everyday spaces of African migration in the mid-sized city of Ghent. One manifestation of African spatiality is discussed in-depth in relation to its (in)visibility and publicity: an African shop located in an ordinary terraced house. With no less than 12 activities taking place in the building, the shop is rather a “public” place than solely a space of commercial transactions, although this is not signaled in very visible ways. By analyzing the modest stylistic appropriations of the façade and the significant re-arrangements of the buildings’ interior spaces that challenge more conventional usages of spaces in Ghent’s ordinary houses, this chapter puts this African shop to the fore as emblematic of how the process of materialization of transnational lifestyles and connections is always a balancing act between the visibility necessary for functioning as a (semi-)pubic place and the invisibility required to circumvent hegemonic regulatory regimes

SIRNA-Directed In Vivo Silencing of Androgen Receptor Inhibits the Growth of Castration-Resistant Prostate Carcinomas

BACKGROUND: Prostate carcinomas are initially dependent on androgens, and castration or androgen antagonists inhibit their growth. After some time though, tumors become resistant and recur with a poor prognosis. The majority of resistant tumors still expresses a functional androgen receptor (AR), frequently amplified or mutated. METHODOLOGY/PRINCIPAL FINDINGS: To test the hypothesis that AR is not only expressed, but is still a key therapeutic target in advanced carcinomas, we injected siRNA targeting AR into mice bearing exponentially growing castration-resistant tumors. Quantification of siRNA into tumors and mouse tissues demonstrated their efficient uptake. This uptake silenced AR in the prostate, testes and tumors. AR silencing in tumors strongly inhibited their growth, and importantly, also markedly repressed the VEGF production and angiogenesis. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that carcinomas resistant to hormonal manipulations still depend on the expression of the androgen receptor for their development in vivo. The siRNA-directed silencing of AR, which allows targeting overexpressed as well as mutated isoforms, triggers a strong antitumoral and antiangiogenic effect. siRNA-directed silencing of this key gene in advanced and resistant prostate tumors opens promising new therapeutic perspectives and tools