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Notes: Hafnium and zirconium silicate (HfSixOy and ZrSixOy, respectively) gate dielectric films with metal contents ranging from ∼3 to 30 at. % Hf, or 2 to 27 at. % Zr (±1 at. % for Hf and Zr, respectively, within a given film), have been investigated, and films with ∼2–8 at. % Hf or Zr exhibit excellent electrical properties and high thermal stability in direct contact with Si. Capacitance–voltage measurements show an equivalent oxide thickness tox of about 18 Å (21 Å) for a 50 Å HfSixOy (50 Å ZrSixOy) film deposited directly on a Si substrate. Current–voltage measurements show for the same films a leakage current of less than 2×10−6 A/cm2 at 1.0 V bias. Hysteresis in these films is measured to be less than 10 mV, the breakdown field is measured to be EBD∼10 MV/cm, and the midgap interface state density is estimated to be Dit∼1–5×1011 cm−2 eV−1. Au electrodes produce excellent electrical properties, while Al electrodes produce very good electrical results, but also react with the silicates, creating a lower ε layer at the metal interface. Transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy indicate that the dielectric films are amorphous silicates, rather than crystalline or phase-separated silicide and oxide structures. TEM shows that these films remain amorphous and stable up to at least 1050 °C in direct contact with Si substrates. © 2000 American Institute of Physics.

Notes: An optical sensor containing polarizing optical components has been constructed to monitor fluorescence anisotropy during polymer processing and to carry out remote sensing of polymer products doped with fluorescent dyes. The sensor is a compact unit that is used to polarize incident excitation light as well as to analyze the polarization of generated fluorescent light. Optical fibers are used to carry light between the sensor head and the light source and detecting equipment. The anisotropy measurement yields information about the orientation of a fluorescent dye molecule that has been doped into polymer matrix. Fluorescent dyes that have geometrical asymmetry in their molecular structure are used. Experiments are described for which the sensor is positioned in line during extrusion, during specimen extension, and where the sensor is used to carry out area scans of films and sheets. Measurements were made on polyethylene, polyethylene terephthalate, and polybutadiene resins that contained a low concentration of fluorescent dye.

Notes: In this study we examine whether stabilization of denuded coastal foredunes in southeastern Australia with the exotic grass species Ammophila arenaria (marram grass) restores plant and ground-active arthropod assemblages characteristic of undisturbed foredunes. Vascular plants and arthropods were sampled from foredunes that had been stabilized with marram grass in 1982, and from foredunes with no obvious anthropogenic disturbance (control dunes). All arthropods collected were sorted to Order, and ants (81.5% of all specimens) were further sorted to morphospecies. Abundance within arthropod Orders, as well as richness, composition, and structure of the plant and ant assemblages from control and stabilized dunes, were compared. The abundance of Diptera was significantly greater on stabilized dunes, while the abundance of Isopoda was significantly greater on control dunes. There were no significant differences in morphospecies richness or composition of ant assemblages on the two dunes types, although some differences in the abundances of individual morphospecies were observed. By contrast, stabilized dunes exhibited lower plant species richness and highly significant differences in plant species composition, due mainly to the large projected foliage cover of marram grass. The study revealed that after 12 years, the vegetation composition and structure of stabilized dunes was still dominated by marram grass and, as a result, invertebrate assemblages had not been restored to those characteristic of undisturbed foredunes.

Notes: Objectives 1. To determine the prevalence of endometrial hyperplasia in postmenopausal women taking standard proprietary regimens of sequential oestrogen/progestogen; 2. to determine the effects of nine months treatment with an oral continuous combined regimen of 2 mg 17ß-oestradiol and 1 mg norethisterone acetate (Kliofem [Kliogest outside the UK]; Novo Nordisk, Denmark) on endometrial histology in postmenopausal women.Design An open, prospective study in postmenopausal women.Setting Fifty-four menopause clinics in the UK.Participants 2028 postmenopausal women: 1312 (Group A) taking sequential oestrogen-progestogen hormone replacement therapy (HRT), and 716 (Group B) not taking HRT, were recruited. In Group A, 388 women took preparations containing 10 days of progestogen, 921 had 12 days, and 3 had 13 days per cycle.Methods Endometrial aspiration biopsies were taken towards the end of a three-month run-in period (Group A) or at study entry (Group B), before administration of the continuous combined HRT regimen. Biopsies were repeated at the end of the nine month treatment period.Main outcome measure Endometrial histology.Results Initial endometrial biopsy data were available for 1106 women in Group A, who by the time of endometrial investigation had been taking HRT for a median duration of 2.56 years (5th to 95th centiles: 0.77 to 8.49 years). Data were available for 661 untreated women, who had no bleeding and had not taken HRT within the last year (Group B). Complex hyperplasia was found in 59 women (5.3%), and atypical hyperplasia in a further eight (0.7%) in Group A. In Group B there were no cases with complex hyperplasia, but one woman showed atypical hyperplasia (0.2%). At the end of the nine months of continuous combined therapy there was no case of hyperplasia among 1196 biopsies (upper 95% confidence limit of risk 0.31%) in women completing the study. Within this Group all of the women with complex hyperplasia arising during previous sequential HRT and who completed the study (n= 38) reverted to normal endometrial patterns. There was no case of endometrial carcinoma during the study.Conclusions Despite taking standard regimens of sequential HRT containing at least 10 days of progestogen, there was a 5.3% prevalence of complex endometrial hyperplasia, and a 0.7% prevalence of atypical hyperplasia. However, continuous combined HRT (Kliofem) containing daily progestogen is not associated with an increased risk of hyperplasia and will convert the endometrium to normal in those with complex hyperplasia arising during previous sequential HRT.

Notes: This investigation examines the ability of the theory of reasoned action (TRA) to explain and predict adolescents' verbal (i.e., insulting) and physical (i.e., fighting) aggression, as well as behaviors that encourage aggression such as watching a fight or telling others about a fight that is going to happen. Subjects were 488 seventh-grade boys and girls enrolled in 2 public junior high schools in a large Midwestern U.S. city. Subjects completed a survey assessing components of the TRA as they related to the 4 behaviors under investigation. Consistent with the TRA, analysis revealed that attitudes and subjective norms predicted behavioral intent, and intent predicted behavior, for watching a fight, spreading rumors about a fight, and insulting. For fighting, however, attitudes, but not subjective norms, predicted behavioral intent, and intent predicted behavior. Implications for the TRA as well as for the development of youth violence prevention and intervention programs are discussed.

Notes: The idea of human rights has become one of the central moral notions of both the theory and practice of international politics. While its foundation and future in the practice of politics looks bright, it is an idea that still causes great trouble at the theoretical level. What are human rights? Why do we have them? To what should we attribute the authority of their moral claims? The theorist Michael Freeman has suggested one theory that by addressing such questions may serve as a foundation for human rights. His theory, however, ends by begging the questions it set out to answer.

Notes: The response regulator proteins of two-component systems mediate many adaptations of bacteria to their ever-changing environment. Most response regulators are transcription factors that alter the level of transcription of specific sets of genes. Activation of response regulators requires their phosphorylation on a conserved aspartate residue by a cognate sensor kinase. For this reason, expression of a recombinant response regulator in the absence of the requisite sensor kinase is expected to yield an unphosphorylated product in the inactive state. For Spo0A, the response regulator controlling sporulation in Bacillus subtilis however, we have found that a significant fraction of the purified recombinant protein is phosphorylated. This phosphorylated component is dimeric and binds to Spo0A recognition sequences in DNA. Treatment with the Spo0A-specific phosphatase, Spo0E, leads to dissociation of the dimers and loss of DNA binding. It is therefore necessary to pre-treat recombinant Spo0A preparations with the cognate phosphatase, to generate the fully inactive state of the molecule.

Notes: A 62-year-old man was evaluated for chronic recurrent pyoderma gangrenosum (PG) of 8 years’ duration. He had a long history of acne conglobata beginning in his early twenties. Although periods of inactivity lasted for months, renewed cyst formation recurred on the face, trunk, and groin. Minocycline, 100 mg twice daily, was useful for the control of acne.Severe periodontal disease developed 25 years prior to presentation. He had coronary bypass surgery 12 years ago. His family history was noncontributory and negative for PG, acne conglobata, or follicular occlusion (FO) triad.The patient presented with an 8-year history of small hemorrhagic pustules on the legs, progressing over the subsequent few months to large ulcers with raised borders. Spikes in temperature and general malaise for 3 or 4 days sometimes heralded new PG eruptions.On examination, large inflammatory, scarring cysts were present, predominantly on the face, lateral neck, back, and inguinal areas. Both lower legs showed small hemorrhagic pustules and scattered ulcers with raised, irregular borders (〈link href="#f1 #f2 #f3"〉Figs 1–3). The larger ulcers often began as painful nodules, with central necrosis; peripheral expansion led to the formation of a central mucopurulent base surrounded by an undermined, ragged, erythematous or dusky, edematous ulcer rim. A vague, serpiginous halo of erythema surrounded these lesions.〈figure xml:id="f1"〉1〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1682:IJD_1682_f1"/〉Multiple necrotic ulcerations of pyoderma gangrenosum on the leg, demonstrating raised, inflammatory borders, a mucopurulent base, and a surrounding halo of erythema. Cribriform scarring is also apparent〈figure xml:id="f2"〉2〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1682:IJD_1682_f2"/〉Characteristic ulcer of pyoderma gangrenosum consists of a boggy, necrotic base with ragged, undetermined, violaceous edges surrounded by a halo of erythema〈figure xml:id="f3"〉3〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1682:IJD_1682_f3"/〉Close up of leg ulcer in 〈link href="#f2"〉Fig. 2 A biopsy specimen taken from the erythematous border of a leg ulcer showed a massive neutrophilic infiltrate with necrotizing suppurative inflammation and limited necrotizing vasculitis; direct immunofluorescence examination gave nonspecific results. Thrombosis of the small vessels, edema, and extravasation of erythrocytes were also noted. These histologic findings support the clinical diagnosis of PG.Serum protein electrophoresis revealed a monoclonal, immunoglobulin A (lgA) kappa-type gammopathy. Bone marrow evaluation showed a slight elevation of plasma cells, suggesting a benign monoclonal gammopathy; urine analysis did not demonstrate Bence-Jones protein. Evaluation for gastrointestinal, liver, and hematologic disease was negative. A complete blood cell count and blood chemistries gave results within normal limits.Oral prednisone, 60 mg daily, dapsone, 200 mg daily, and trimethoprim/sulfamethoxazole DS, twice daily, were administered. Prednisone was reduced to 30 mg every other day when the large ulcers of the legs ceased to expand, and regression was noted. Cribriform scarring was seen in areas of healing. Systemic prednisone eventually produced noticeable side-effects, including bilateral cataract formation and the development of tachycardia. Isotretinoin was begun with excellent initial results, but the patient had to discontinue therapy due to frontal headaches, scleral hemorrhage, the development of painful heel pads, and elevated hepatic function tests. The patient remained on minocycline, 100 mg twice daily, with relatively good control of the acne. Pustules were treated adequately with topical corticosteroids; larger ulcers were well controlled with intralesional corticosteroids and short courses of oral prednisone. Colchicine, 0.6 mg twice daily, and dapsone, 100 mg twice daily, were continued at maintenance levels for several years, and topical clobetasol propionate was applied to new lesions as they appeared.