bluuebunny/crossref_metadata_2025 huggingface dataset:
Nano‐Scale Design of TiAl Alloys Based on β‐Phase Decomposition
Authors: Appel F. , Oehring M. , Paul J. D. H.
Published: May 2006

Phase decomposition and ordering reactions in β/B2‐phase containing TiAl alloys were utilized to establish a novel, previously unreported, type of laminate microstructure. The characteristic constituent of this microstructure are laths with a nanometer‐scale substructure that are comprised of several stable and metastable phases. Microstructural control can be achieved by conventional thermomechanical processing and leads to a structurally and chemically very homogeneous material with excellent mechanical properties. The physical metallurgy of this novel type of alloy has been assessed by transmission electron microscope investigations and mechanical testing.
Polarized Raman scattering and phase transition studies of n‐diethylenediammonium monohydrogenmonophosphate dihydrate
Authors: Elleuch S. , Feki H. , Abid Y. , Mlayah A.
Published: May 2006

Polarized Raman scattering studies at room temperature were carried out on N‐diethylenediammonium monohydrogenmonophosphate dihydrate single crystal samples, abbreviated N‐DDHP. An assignment of the normal modes is proposed based on group theory analysis and correlations with previous data reported for other homologous hydrogen‐bonded systems. A careful analysis of the vibrational spectra shows that the assignment of the fundamental vibrational modes can be done based on phosphate, organic and water group vibrations. In addition, differential scanning calorimetry measurement and a Raman spectroscopic study at several temperatures in the range 100–300 K are presented. The occurrence of a low‐temperature phase transition near 220 K is well evidenced. From the temperature‐dependence behavior of some internal and external modes, this transition is interpreted by an order–disorder transition which involves the structural modifications of both anion and cation groups. Copyright © 2006 John Wiley & Sons, Ltd.
Simultaneous determination of aromatic and terpenic constituents of cloves by means of HPLC with diode array detection
Authors: Musenga Alessandro , Ferranti Anna , Saracino Maria Addolorata , Fanali Salvatore , Raggi Maria Augusta
Published: May 2006

An HPLC method has been developed for the simultaneous determination of aromatic and terpenic constituents of cloves on a C8 RP column, with the mobile phase consisting of a pH 3.5 phosphate buffer‐triethylamine (30%) and acetonitrile (70%); a flow rate of 1.2 mL/min and a diode‐array detector were used. Complete separation of all analytes (eugenol (EUG), eugenol acetate (AEUG), β‐caryophyllene, α‐humulene and caryophyllene oxide) was achieved within 7 min. Good linearity was found in the range 0.125–40.0 μg/mL for EUG and AEUG and in the range 0.250–20.0 μg/mL for the terpenic compounds. After validation, the method was successfully applied to the analysis of clove oil and clove extract samples. The results obtained indicate good accuracy (recovery percentage mean value corresponding to 99.9%) and satisfactory precision.
Dense subtrees in complete Boolean algebras
Authors: König Bernhard
Published: May 2006

We characterize complete Boolean algebras with dense subtrees. The main results show that a complete Boolean algebra contains a dense tree if its generic filter collapses the algebra's density to its distributivity number and the reverse holds for homogeneous algebras. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silica‐supported bis(imino)pyridyl iron(II) catalyst: nature of the support–catalyst interactions
Authors: Ray Saptarshi , Sivaram Swaminathan
Published: May 2006

Ethylene polymerizations were performed using silica‐supported 2,6‐bis[1‐(2,6‐diisopropylphenylimino) ethyl] pyridine iron(II) dichloride with methylaluminoxane (MAO) as co‐catalyst. Silica was calcined at 600, 400 and 200 °C under vacuum for 8 h. The effect of calcination temperature of silica on the polymerization activity and the properties of the polymers obtained were examined. Catalyst–support interactions were examined by both a chemical method and XPS. It was observed that upon supporting the catalyst on the surface of silica, there is an increase in the binding energy of the metal center. However, no change in the metal binding energy was observed on supporting the catalyst to silica calcined at different temperatures. Ethylene polymerizations were performed using MAO as co‐catalyst. Catalysts were also prepared by first pretreating silica with MAO, followed by addition of the Fe(II) catalyst and contacting a complex of Fe(II) catalyst–MAO with silica previously calcined at 400 °C for 8 h. The results indicate that there is no chemical bonding between the support and the catalyst. Copyright © 2006 Society of Chemical Industry
Flame retardancy of different‐sized expandable graphite particles for high‐density rigid polyurethane foams
Authors: Shi Lei , Li Zhong‐Ming , Xie Bang‐Hu , Wang Jian‐Hua , Tian Chun‐Rong , Yang Ming‐Bo
Published: May 2006

The effects of expandable graphite (EG) of different particle sizes, on the fire‐retardant properties of high‐density rigid polyurethane foam (RPUF) (0.45 g cm−3) were studied. Samples of EG with different particle sizes were obtained by pulverization in an ultra‐high‐speed mixer for 4 and 13 min, respectively. It was shown that as received (EG0) and 4 min pulverized EG (EG4) efficiently improved the fire‐retardant properties of RPUF composites, while 13 min pulverized EG (EG13) did not. The char of the burned composites filled with EG0 and EG4 covered the whole surface of the samples and formed a complete physical barrier. This barrier material prevented combustible gases from feeding the flame and also isolated oxygen efficiently from the burning material. EG13 did not produce enough char to cover the whole surface of the burning sample, resulting in poor fire‐retardant property of the RPUF composites. Thermal degradation tests of the foams by thermogravimetric analysis indicated that EG showed negligible effects on the thermal stability of the RPUFs. Copyright © 2006 Society of Chemical Industry
Ligand‐field splitting of the energy levels of Nd3+ (4f3) in 2‐hydroxyethyl methacrylate polymer (HEMA)
Authors: Gruber John B , Sardar Dhiraj K , Johnson Dave , Yow Raylon M , Coeckelenbergh Cody H , Nijjar Anmol S
Published: May 2006

Detailed absorption spectra of trivalent neodymium (Nd3+) in 2‐hydroxyethyl methacrylate polymer (HEMA) are reported at cryogenic temperatures and at wavelengths between 440 and 900 nm. The Nd3+ spectra are confirmed by comparison with spectra of HEMA samples prepared without inclusion of the rare earth ion. The structure observed on the absorption bands can be interpreted in terms of the ligand‐field (crystal‐field) splitting of the energy levels of Nd3+ (4f3) for multiplet manifolds, 4F3/2, 4F5/2, 2H9/2, 4F7/2, 4S3/2, 4F9/2, 2H11/2, 4G5/2, 2G7/2, 4G7/2, and 2K13/2. The Nd3+ ions are complexed as species made up of nitrate anions and H2O molecules that come from the neodymium nitrate hydrate salt used in the preparation of the doped HEMA sample. The local symmetry of the Nd3+ ion in HEMA is very low (possibly CS), and a number of different environments are likely for the neodymium species in the HEMA structure. We have calculated the ligand‐field splitting of the Nd3+ energy levels using a point charge/dipole model for one such possible species, Nd(NO3)3 · xH2O− (x = 5–6). The results of the model give an agreement of 10 cm−1 (rms) between 43 observed‐to‐calculated ligand‐field (Stark) levels. Comparisons between these same calculated levels and observed levels obtained for Nd3+ in crystalline hydrated nitrate salts and certain Nd3+‐doped glasses also give good agreement and support a better understanding of the environment of Nd3+ in a polymeric structure. Copyright © 2006 Society of Chemical Industry
Impact of III/V ratio on polytype and crystalline quality of AlN grown on 4H‐SiC (11$ \bar 2 $0) substrate by molecular‐beam epitaxy
Authors: Horita M. , Suda J. , Kimoto T.
Published: May 2006

The impact of the III/V ratio during growth on the polytype and crystalline quality of nonpolar AlN grown on 4H‐SiC (11$ \bar 2 $0) was investigated. Growth of AlN was carried out by molecular‐beam epitaxy (MBE) using elemental Al and rf‐plasma excited nitrogen. Polytype replication from the SiC substrate to the grown AlN epilayer occurred under Al‐rich conditions, i.e., 4H‐AlN (11$ \bar 2 $0) was grown on 4H‐SiC. On the other hand, the thermally stable 2H‐AlN (11$ \bar 2 $0) polytype was grown under N‐rich conditions. The best crystalline quality of AlN was obtained for slightly Al‐rich conditions. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy gaps and bowing parameters of InAlGaN ternary and quaternary alloys
Authors: Androulidaki M. , Pelekanos N. T. , Tsagaraki K. , Dimakis E. , Iliopoulos E. , Adikimenakis A. , Bellet‐Amalric E. , Jalabert D. , Georgakilas A.
Published: May 2006

We report a study of band gap energies and bowing parameters of all possible families of ternary and quaternary nitride alloys. The experimental band gap energies (E g) measured by photoluminescence, optical transmission and reflection methods, were strain‐corrected in order to obtain for every sample the unstrained value of its E g. For Alx Ga1–x N the bowing parameter is equal to 1 eV, but the alloys Inx Ga1–x N and Inx Al1–x N exhibited strong dependence of the bowing parameter on alloy composition. Finally, we investigated many quaternaries alloys Inx Aly Ga1–x –y N and we observed that the bowing parameter appears also to be very sensitive on In content. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the incorporation mechanism of Fe in GaN grown by metal‐organic vapour phase epitaxy
Authors: Balmer R. S. , Soley D. E. J. , Simons A. J. , Mace J. D. , Koker L. , Jackson P. O. , Wallis D. J. , Uren M. J. , Martin T.
Published: May 2006

We report an investigation of the incorporation mechanism of iron (Fe) as a dopant in GaN grown by MOVPE. A series of Fe doped GaN structures were studied by secondary ion mass spectrometry (SIMS), atomic force microscopy (AFM) and X‐ray photo‐electron spectroscopy (XPS). A model is presented which describes the SIMS concentration profiles with excellent agreement, and, it is shown that Fe incorporation into GaN occurs via a surface segregation mechanism. This model is supported by direct measurement of a highly Fe‐rich layer on the surface of Fe doped GaN by XPS. Furthermore, we find that the presence of Fe on the GaN surface promotes a transition from 2D to 3D GaN growth which is confirmed by AFM measurements of RMS roughness with increasing Fe flux. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and characterization of Ni‐based Schottky‐type AlxGa1–xN ultraviolet photodetectors with different buffer conditions
Authors: Park Ki Yon , Kwon Bong Joon , Son Jeong Hwan , Cho Yong‐Hoon
Published: May 2006

We investigated the structural, optical, and electrical properties of Ni‐based Schottky type AlxGa1–xN ultraviolet (UV) photodetectors. Three different types of AlxGa1–xN/GaN heterostructures were epitaxially grown on (0001) sapphire substrates by metal‐organic chemical vapor deposition. We found that the thin AlxGa1–xN layer directly grown on the optimized GaN buffer layer showed the most excellent crystal quality and opto‐electrical properties of Ni‐based Schottky type UV photodetectors. We obtained a dark current of 0.1 nA at –1 V, a responsivity of 0.150 A/W at zero bias, and a specific detectivity D* of 1.28 × 1014 cmHz1/2W–1 at λ = 300 nm for UV photodetectors with a 0.15‐µm‐thick AlxGa1–xN layer directly grown on a 3‐μm ‐ thick undoped GaN layer. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative strain analysis of GaN/AlN quantum dot multilayers
Authors: Sarigiannidou E. , Andreev A. D. , Monroy E. , Daudin B. , Rouvière J. L.
Published: May 2006

The strain distribution in vertically‐correlated GaN quantum dot layers embedded in an AlN matrix is investigated from high‐resolution transmission electron microscopy images. The quantitative strain analysis is realized using the geometrical phase analysis. The obtained results are further supported by elastic theoretical calculations carried out using a combination of Fourier transform and Green's function techniques. We find that the AlN spacers situated between consecutive wetting layers are almost fully relaxed. On the contrary, the AlN spacers located between the vertically correlated GaN quantum dots (QDs) are found to be in a tensile strain state. This local strain is generated by the GaN QDs on the surrounding AlN matrix and causes the vertical alignment of the dots inside the multilayer structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In‐vitro responses to ascorbate and manganese in fibroblasts from a patient with prolidase deficiency and iminodipeptiduria: Cell growth, prolidase activity and collagen metabolism
Authors: Myara I. , Charpentier C. , Wolfrom C. , Gautier M. , Lemonnier A. , Larregue M. , Chamson A. , Frey J.
Published: May 2006

After successful ascorbate and manganese treatment of a female patient with prolidase deficiency and iminodipeptiduria, we attempted to explain the mechanism of action of these drugsin vitro, using them preferentially on skin fibroblasts. Sincein vivo, ascorbate and manganese seemed to be responsible for both biochemical and clinical improvement, they were also expected to activate prolidase activityin vitro. Cell growth and prolidase activity were accordingly observed in fibroblast cultures supplemented with these compounds. It seemed that only ascorbate accounted for the successfulin vivo response. To understand the mechanism involved, we studied collagen metabolism and found a decreased proline pool, a massive increase of rapidly degraded collagen and moderate enhancement of type III collagen and type I trimer in the patient's fibroblasts. We believe that ascorbate allowed the prolidase‐deficient cells to maintain a normal collagen pool by increasing collagen synthesis. Both the massive increase in cell growth in response to ascorbate and the bad response as regards the quality of the collagen produced confirm the secondary nature of this mechanism. However, the relationship between accelerated collagen catabolism and prolidase deficiency remains unclear.
Testicular tumors in children
Authors: Filler Robert M. , Hardy Brian E.
Published: May 2006

Although relatively rare, testicular neoplasms affect a significant number of young children each year. The most common tumor is embryonal carcinoma. With proper management, which includes orchiectomy and retroperitoneal lymph node dissection, survival rates as high as 80% can be expected for children with stage A disease. The use of adjunctive chemotherapy in early stages of embryonal carcinoma may reduce the failure rate even further. Salvage of more advanced cases is possible with the addition of chemotherapy and radiation. Similar results have been obtained in the treatment of other malignant tumors of childhood. Benign tumors of the testis are less frequent than malignant ones and present no special problems in management.
Restraint‐induced stress ulcer. I. Hypothalamic, urinary, and adrenal biochemical studies
Authors: Balibrea Jose L. , Gomez Jose , Alemany Jose R. , Aznar Jose , Canela Mercedes , Castells Enrique , Fernandez Jose L. , Barreno Pedro G. , Ruiz Javier
Published: May 2006

The purpose of these experiments was to study the incidence of stress ulcers in restrained rats and to correlate it with hypothalamic and adrenal cortical and medullary activity, with and without vagotomy. A total of 217 adult rats were used, grouped into 56 sets, and distributed at random in 5 experimental groups. Restraint was followed by a 79% incidence of ulceration in the glandular portion of the gastric mucosa. Vagotomy made these worse (p<0.01). Hypothalamic levels of catecholamines and serotonin showed no significant changes. Urinary measurements revealed decreased excretion of 17‐ketosteroids (p<0.001), increased excretion of uropepsinogen (p<0.01), and no significant changes in vanillylmandelic acid among the rats submitted to immobilization. In the adrenal glands of stressed animals, there was a decreased level of catecholamines (p<0.01) and no significant changes in corticosteroid content (17‐ketosteroids). These results suggest that hypothalamic stimulation and the participation of the adrenal glands are not essential factors in the pathogenesis of restraint‐induced experimental stress ulcer.
Percutaneous needle arteriography
Authors: McCollum Charles H. , Garcia‐Rinaldi R. , Graham J. M. , Noon George P. , DeBakey Michael E.
Published: May 2006

Successful arterial reconstructive surgery requires exact definition of the occlusive or aneurysmal process and the condition of the distal arterial tree. To define these two parameters, it is essential that arteriography be precise, yet it must be safe and reproducible. At our institution, we continue to utilize percutaneous needle arteriography because of its safety and excellent delineation of the vascular system. The purpose of this paper is to discuss our indications, techniques, and results of percutaneous arteriography for evaluation of peripheral arterial disease. During 1975, 1,253 percutaneous arteriograms were performed under general anesthesia by the surgical team. The techniques for carotid, vertebral (retrograde brachial), and femoral arteriograms, and translumbar aortograms will be reviewed. There were no deaths and only 8 (0.7%) complications. We believe that this technique provides an excellent method for good preoperative evaluation of the arterial system of the peripheral arteries and abdominal aorta.
Treatment of benign strictures of the bile ducts
Authors: Fernández Manuel
Published: May 2006

In 2720 operations on the bile ducts, we have repaired 52 strictures caused by accidental injuries. In 39 cases the strictures were located at the level of the bifurcation of the common hepatic duct. The surgical treatment in 39 cases consisted of left hepaticojejunostomy described by Hepp‐Couinaud, which involves a side‐to‐side anastomosis between a defunctionalized jejunal limb and the left hepatic duct. The average size of the anastomotic stoma was 35 mm in diameter. A single layer of interrupted sutures of absorbable material was used. No internal drains or stents were employed. Clinical and laboratory follow‐up examinations carried out between 1 and 10 years postoperatively showed excellent results in all cases. There were no recurrences of stricture and no surgical or postoperative deaths. Morbidity rate was low and was due mainly to some infections of the surgical wound and small drainage of bile in the immediate postsurgical period. All the patients treated were able to return to normal life within a period of 15 to 20 days.
Surgical application of tissue adhesives
Authors: Petrovsky Boris V. , Gigaury Vladimir S. , Milonov Oleg B. , Perelman Michael I. , Mlinchik Vyacheslav E. , Gotye Sergey V. , Safarov Iskandar S.
Published: May 2006

A new technique of application of cyanoacrylate tissue adhesive has been evaluated in 180 patients with wounds of the liver (77 patients), spleen (12 patients), pancreas (9 patients), and lung (82 patients). The technique involves injection of the tissue adhesive with a specially adapted jet injector, so that it penetrates 3–5 mm deep into the parenchyma to form an adhesive plug. The cyanoacrylate adhesive was tolerated without complications, and was highly successful in controlling bleeding, leakage of bile and pancreatic juice, and leakage of air. The adhesive plugging technique warrants widespread application in the surgery of parenchymatous organs.
Dermatitis due to zinc deficiency associated with prolonged malnutrition and total parenteral nutrition
Authors: Hamit Harold F. , David Hamer E. , Stevens James C.
Published: May 2006

Zinc is an essential element in over 70 metalloenzymes that are involved in a wide variety of biochemical reactions and physiological processes such as synthesis of RNA and DNA, the immune response, wound healing, growth and development, utilization of vitamin A, and maintaining the integrity of membranes of cells and organelles. Zinc deficiencies are rare under normal circumstances because the usual diets throughout the world contain ample zinc to meet normal human daily requirements of about 15 mg. Deficiencies of zinc usually result from unusual diets with high cereal content and little or no animal proteins, and are manifested clinically by such disorders as hypogonadal dwarfism, hepatosplenomegaly, anemia teratogenesis, impaired senses of taste and smell, and dermatologic problems, including acrodermatitis enteropathica. We have added 2 case reports to the recently reported cases of acute dermatoses, with lesions resembling those of acrodermatitis enteropathica, associated with total parenteral nutrition and due to zinc deficiency resulting from inadequate intake of zinc and increased excretion of zinc in patients who already may have been depleted from nutritional disturbances that placed them in a catabolic state. Amino acid solutions for total parenteral nutrition, especially the newer crystalline amino acid solutions, contain amounts of zinc that are inadequate for these patients. The acute dermatoses resemble impetigo caused by bacteria, yeast, or fungi, but do not respond to appropriate treatment for these kinds of lesions. They respond readily to parenteral zinc therapy and probably can be prevented by giving adequate zinc parenterally during total parenteral nutrition.
Diaphanography: A method for evaluation of the female breast
Authors: Ohlsson Björn , Gundersen Jörgen , Nilsson Dag‐Martin
Published: May 2006

Diaphanography involves transillumination of the breast with photographic registration on an intrared film. It has been used to evaluate 2 populations of patients. First, 200 women referred to our hospital were examined. In 107 patients operation was performed and the results were compared to the preoperative diaphanographic investigation. There was a good correlation between the preoperative and operative findings. Second, 1575 women without symptoms from the breast were investigated and 11 cancers were found in 10 patients. The diaphanographic method is of value both as a screening technique and as an aid in classifying palpable tumors of the breast.
The potential impact of needle biopsy on surgery for thyroid nodules
Authors: Block Melvin A. , Miller J. Martin , Kini Sudha R.
Published: May 2006

Current techniques with fine and cutting needle biopsies permit greatly improved selection of patients with thyroid nodules for operation. A diagnosis of definite or probable carcinoma was confirmed in 95% of 76 patients, and the addition of the category of indeterminate cellular nodule resulted in an overall frequency of carcinoma in 86%. Therefore, the frequency of operations for benign thyroid nodules was dramatically decreased. Critical for the use of needle biopsy of the thyroid is experience in obtaining an adequate and representative sample of the nodule, as well as in cytologic and histologic interpretation of the tissue. Results of needle biopsy of thyroid nodules should be correlated with clinical findings even though the latter criteria provide a much less accurate index of the need of operation.

The frequency of carcinoma in patients selected for operation can be increased from the 15% to 30% experienced in the past to a level of approximately 85% by needle biopsy. Thyroid nodules that are recognized as cellular by needle biopsy, but in which carcinoma cannot be ruled out should be treated surgically. Improved selectivity for operation for thyroid nodules has not yet significantly reduced the total number of patients undergoing operation in our practice. Some thyroid nodules that would have been treated nonoperatively in the past are now recognized as needing surgery. Operative eradication of nodules that have been considered clinically benign and managed as such in the past, but which are now recognized as being actual or possible carcinoma by needle biopsy conceivably will reduce the frequency of anaplastic or invasive carcinoma in the future. Falsenegative results have been recognized in 1% or less of patients. A preoperative diagnosis of thyroid carcinoma by needle biopsy permits an immediate, definitive surgical procedure, and changes the operative approach for such patients. Needle biopsy of thyroid nodules can reduce procrastination in making a decision for a surgical or medical approach to the management of thyroid nodules.
Urinary complications of Crohn's disease
Authors: Kyle James
Published: May 2006

A 22‐year review of 328 patients with Crohn's disease revealed 70 patients with urinary tract symptoms. Cystitis was the most common problem, occurring in 44 patients. The urinary tract infections were recurrent in most patients, usually with 3 or 4 attacks per year. Despite the persistence of urinary infection, only 3 patients developed chronic pyelonephritis. Forty‐nine patients had intravenous urography, and many were found to have slight dilatation of the upper urinary tract on one side. Seven patients had hydronephrosis, 3 with pyonephrosis. Five of 6 patients who developed calculi had a bowel resection. All of the recovered calculi were oxalate stones, but 3 were passed spontaneously and not analyzed. Eight patients, 7 of them males, had an ileovesical fistula. In 1, the colon was also affected. It was unusual for these patients to have severe urinary symptoms. One patient had a fistula from the rectum to the urethra. Although 32 of the 70 patients were female, most of the severe complications occurred in men. Aggressive investigation is not indicated, nor is radical surgery required.
The incidence and prevalence of inflammatory bowel disease in north Tees health district
Authors: Devlin H. Brendan , Datta D. , Dellipiani A. W.
Published: May 2006

The experience with inflammatory bowel disease in a stable, defined population in northeast England is described. In this population, the incidence of inflammatory bowel disease was higher than expected. In particular, a high incidence of colorectal and anal Crohn's disease was found. The literature is reviewed in order to identify some of the factors responsible for this unusual prevalence of inflammatory bowel disease in the study population. No explanation for our unexpected findings can be advanced.
The epidemiology of leptospirosis and the emergence of Leptospira borgpetersenii serovar Arborea in Queensland, Australia, 1998–2004
Authors: SLACK A. T. , SYMONDS M. L. , DOHNT M. F. , SMYTHE L. D.
Published: May 2006

Leptospirosis is one of the most commonly encountered zoonoses in both Australia and the rest of the world. The incidence of leptospirosis in Queensland over the 7-year study period (1998–2004) was 3·1/100000 population. Enhanced surveillance questionnaires were used to collect patient data and facilitate an epidemiological investigation of leptospirosis in Queensland. Farming occupations comprised the majority of occupational exposure cases, however, recreational exposure accounted for 18% of the 883 cases. Rainfall and the presence of animal hosts had the most influence on the incidence of leptospirosis. Several trends in serovar numbers over this period are noted, in particular the emergence of L. borgpetersenii serovar Arborea, which accounted for 22% of all leptospirosis cases in Australia and 68% of South-East Queensland cases in 2004. Assessment of epidemiological trends in leptospirosis is important to obtain directed public health intervention and outcomes in the reduction of leptospirosis cases.
The payout stage in Chile: who annuitizes and why?
Authors: JAMES ESTELLE , MARTINEZ GUILLERMO , IGLESIAS AUGUSTO
Published: May 2006

In 1981 Chile adopted its new multi-pillar system, which featured privately managed individual accounts. Starting in 1983 payouts from the accounts were permitted and detailed rules about payouts were put in place. The Chilean scheme therefore gives us an opportunity to examine how pensioners and pension providers react when individual accounts replace DB systems, and how detailed regulations shape these reactions.

Retirees in Chile have a choice between early versus normal retirement (before or after age 65M/60W) and between annuitization versus programmed withdrawals; lump sum withdrawals are largely ruled out. Almost two-thirds of all retirees have annuitized – a very high proportion compared with other countries. This paper argues that this high rate of annuitization is the result of guarantees and regulations that constrain payout choices, insure retirees through the minimum pension guarantee, eliminate other DB components, and give a competitive advantage to insurance companies selling annuities. The minimum pension financed by the government provides insurance to workers with small accumulations, who retire at the normal age with programmed withdrawals, while those with large accumulations retire early and must purchase annuities to acquire longevity and investment insurance. Insurance companies further induce annuitization by marketing aggressively, facilitating early retirement for those who annuitize and offering a high money's worth ratio for price-indexed annuities. We find evidence of adverse selection based on asymmetric information about short-run health status, but this does not seem to deter the high rate of annuitization.
A polarizable continuum approach for the study of heterogeneous dielectric environments
Authors: Iozzi Maria Francesca , Cossi Maurizio , Improta Roberto , Rega Nadia , Barone Vincenzo
Published: May 2006

We present a computational method, exploiting some features of the polarizable continuum model (PCM) to describe heterogeneous media; it belongs to the family of electrostatic embedding mixed methods, such as the more common quantum-mechanical (QM)/molecular mechanics approaches, with the electrostatic long range effects accounted for by a polarized continuum instead of atomic point charges. Provided effective dielectric constants are determined for the various parts of the system, the method is much faster than its atomistic counterpart, and allows for high-level QM calculations on the fragment of interest, using all the highly efficient computational tools developed for homogeneous PCM. Two case studies (the calculation of the pKa of solvent exposed acidic residues in a model protein, and the calculation of the electron spin resonance spectrum of a typical spin probe partially embedded in a membrane) are analyzed in some detail, to illustrate the application of the method to complex systems.
Comment on “On the dielectric susceptibility spectra of supercooled o-terphenyl” [J. Chem. Phys. 123, 154502 (2005)]
Authors: Ferrari C. , Tombari E.
Published: May 2006

We point out that the “master plot” [R. Richert, J. Chem. Phys.123, 154502 (2005)] obtained by normalizing the dielectric loss ε″ by the dielectric relaxation strength Δε is inappropriate because Δε is neither accurately measured when its value is small, nor the high frequency relaxation contribution is eliminated from it. A reliable analysis for change in the distribution of times with temperature is performed by normalizing ε″ by its peak value in the spectra.
Response to “Comment on ‘On the dielectric susceptibility spectra of supercooled o-terphenyl’” [J. Chem. Phys. 123, 154502 (2005)]
Authors: Richert Ranko
Published: May 2006

The recent claim of time-temperature superposition (TTS) for o-terphenyl (OTP) in its viscous regime is revisited in order to clarify whether peak versus area normalization of the dielectric loss profiles impacts the results derived from the master plot. In the case of OTP, noise is the main source of differences between the two options. Using synthetic noisy data, it is shown that an area normalized master plot is more sensitive to deviations from TTS than the peak normalized counterpart. As a result, OTP is characterized by a stretching exponent β=0.50±0.03 in the 248–284K temperature range.
Nosé-Hoover dynamics in a shaker
Authors: Faou Erwan
Published: May 2006

We introduce a new class of systems based on the Nosé-Hoover equations. We show that we can add time-dependent terms without destroying the measure and energy conservation properties of the initial system. These “shakers” are typically pseudoperiodic in time, i.e., depend on a collection of harmonic oscillators. We show by numerical examples that it strengthens the sampling properties of the initial system with respect to the Gibbs measure and helps the computation of averages in the canonical ensemble.
Nitride light-emitting diodes grown on Si (111) using a TiN template
Authors: Chen N. C. , Lien W. C. , Shih C. F. , Chang P. H. , Wang T. W. , Wu M. C.
Published: May 2006

Nitride light-emitting diodes (LEDs) are grown on a Si (111) substrate with a TiN template. Transmission electron microscopy and x-ray diffraction indicate that the epitaxial relation follows Si(1,1,1)‖TiN(1,1,1)‖AlN(0,0,1), Si[1,1,0]‖TiN[1,1,0], and Si[0,0,1]‖TiN[0,0,1]. The reflectance measurement and simulation results indicate that the TiN can be adopted as a reflector to mitigate the substrate absorption problem, thus increasing the extraction efficiency of nitride LEDs grown on Si.
Laa1p, a Conserved AP-1 Accessory Protein Important for AP-1 Localization in Yeast
Authors: Fernández G. Esteban , Payne Gregory S.
Published: May 2006

AP-1 and Gga adaptors participate in clathrin-mediated protein transport between the trans-Golgi network and endosomes. Both adaptors contain homologous domains that act to recruit accessory proteins involved in clathrin-coated vesicle formation, but the spectrum of known adaptor-binding partners is limited. This study describes an evolutionarily conserved protein of Saccharomyces cerevisiae, Laa1p (Yjl207cp), that interacts and functions specifically with AP-1. Deletion of LAA1, when combined with a conditional mutation in clathrin heavy chain or deletion of GGA genes, accentuated growth defects and increased disruption of clathrin-dependent α-factor maturation and transport of carboxypeptidase Y to the vacuole. In contrast, such genetic interactions were not observed between deletions of LAA1 and AP-1 subunit genes. Laa1p preferentially interacted with AP-1 compared with Gga proteins by glutathione S-transferase-fusion affinity binding and coimmunoprecipitations. Localization of AP-1 and Laa1p, but not Gga proteins, was highly sensitive to brefeldin A, an inhibitor of ADP-ribosylation factor (Arf) activation. Importantly, deletion of LAA1 caused mislocalization of AP-1, especially in cells at high density (postdiauxic shift), but it did not affect Gga protein distribution. Our results identify Laa1p as a new determinant of AP-1 localization, suggesting a model in which Laa1p and Arf cooperate to direct stable association of AP-1 with appropriate intracellular membranes.
Educational and dermatological aspects of secondary individual prevention in healthcare workers
Authors: Weisshaar Elke , Radulescu Magdalena , Bock Michael , Albrecht Ursel , Diepgen Thomas L.
Published: May 2006

Healthcare workers (HCW) have an increased risk of suffering from occupational skin diseases (OSDs). Therefore, we established special prevention and skin protection courses for HCW. Medical aims are to optimize diagnostic procedures and individual therapy, educational aims are to improve individual skin protection/skin care habits of the patient and also to influence the participants' attitudes towards health. Participants are patients that have been suspected to suffer from an OSD and are insured with the German Accident Prevention Insurance Association for Health Care Workers (BGW). Teaching units mainly focus on the texture and functioning of the skin, general aspects of OSDs, general information concerning skin protection, instructions about the correct use of skin cleansing and skin protection products. Besides, every participant is clinically examined by a dermatologist and a precise patient's history is obtained. Individually adapted skin protection strategies are developed. Patients can ask the dermatologist questions in confidence. 504 patients (mean age: 36.9 years, SD = 11.7) participated in the skin protection courses. 94.6% (n = 477) suffered from hand eczema frequently caused by a mixture of atopic, irritant and allergic contact dermatitis, but irritant contact dermatitis was the most frequent diagnosis (55.4%, n = 279). The participants rated the course as good to excellent. Health education and advisory services in occupational dermatology are still fragmentary. Prevention of OSD and maintenance of health through education are important complementary measures for dermatological care. In the future, similar educational programmes should be offered for employees of other professions with an increased risk for OSD.
Formaldehyde in reusable protective gloves
Authors: Pontén Ann
Published: May 2006

Due to the clinical findings in a single patient's case, formaldehyde was suspected to be present in clinically relevant levels in reusable protective gloves. Therefore, 9 types of gloves were investigated with the semi‐quantitative chromotropic acid method. It was found that 6/9 gloves emitted some formaldehyde and that 4/9 gloves emitted ≥40 µg of formaldehyde. Most of the formaldehyde was found on the inside of the gloves. To get an indication of the clinical relevance, a comparison with a protective cream declared to contain the formaldehyde‐releasing agent diazolidinyl urea was performed by comparing areas of gloves with areas of cream layers with thickness 1–2 mg/cm2. It was found that the amounts of formaldehyde emitted from the gloves might be in the same range as emitted from a layer of cream.
Pitfalls in drug allergy skin testing: false–positive reactions due to (hidden) additives
Authors: Grims Robert Hermann , Kränke Birger , Aberer Werner
Published: May 2006

Skin testing for drug hypersensitivity is a valuable diagnostic tool and a well established procedure for betalactams and corticosteroids. Although appropriate patch, prick or intracutaneous testing usually permits unequivocal interpretation, the possibility of false–positive reactions must be kept in mind. We report two patients, one with a suspected penicillin allergy and one with a suspected steroid allergy, in whom positive skin tests initially yielded a false diagnosis. In both cases, other findings were inconsistent with the positive skin tests. Therefore, further investigations were performed. After the test preparations had been analysed, the skin test was extended to include the additives, which then yielded the diagnosis of sensitization to the surfactant polysorbate 80 (PS 80, contained in the penicillin test solution) and the emulsion stabilizer carboxymethylcellulose (CMC, contained in the steroid preparation), respectively. It should be noted that positive reactions to test solution additives, as in the first case, may lead to a lifelong false diagnosis of (penicillin) allergy, whereas an undiagnosed allergy to additives in parenteral applications, as in the second case, might prove fatal.
Soluble CD26/CD30 levels in visceral leishmaniasis: markers of disease activity
Authors: Ajdary S , Riazi-Rad F , Jafari-Shakib R , Mohebbali M
Published: May 2006

Leishmania infantum is the causative agent of zoonotic visceral leishmaniasis (VL). If untreated the disease could be fatal; however, in some cases the infection can run a subclinical course. In subclinical infections a Th1-response predominates, while Th2-responses and/or probably Treg cells are related to unfavourable outcome of the disease in active VL. In the present study we determined the levels of soluble (s) CD26 and CD30 co-stimulatory molecules in sera from patients with active VL, asymptomatic individuals and healthy volunteers. Results showed a significant difference in both sCD26 and sCD30 between infected cases and normal individuals (P ≤ 0·001). However, there was no significant difference in sCD26 levels between asymptomatic cases and patients, although the difference was not significant. sCD30 levels were significantly higher in VL patients than asymptomatic cases (P ≤ 0·001). These findings suggest a possible association between sCD26 and sCD30 levels and the clinical manifestation of L. infantum infection.
Contribution of interferon‐β to the immune activation induced by double‐stranded DNA
Authors: Shirota Hidekazu , Ishii Ken J. , Takakuwa Hiroki , Klinman Dennis M.
Published: May 2006

Introducing double‐stranded DNA (dsDNA) into the cytoplasm of macrophages and dendritic cells triggers the activation of these professional antigen‐presenting cells (APCs). This process is characterized by the up‐regulation of costimulatory molecules and the production of various cytokines, chemokines, and antibacterial/viral factors. Current findings indicate that interferon‐β (IFN‐β) plays a key role in the stimulatory cascade triggered by dsDNA. Both immune and non‐immune cells respond to intracytoplasmic dsDNA by up‐regulating IFN‐β) expression, a process that reduces host susceptibility to infection. The immune activation induced by dsDNA is independent of MyD88, TRIF and DNA‐PKcs, indicating that a Toll‐like receptor‐independent mechanism underlies the cellular activation mediated by intracytoplasmic dsDNA.
Anaesthesia for liver transplantation in two infants with an organic acidaemia
Authors: Manzoni Diego , Spotti Angelica , Carrara Bruno , Gritti Paolo , Sonzogni Valter
Published: May 2006

Abstract:  Liver transplantation is an accepted option of treatment in patients with inborn errors of metabolism limited to or mainly located into hepatocytes who have not responded well to medical treatment. Recurrent metabolic failure and neurological impairment might be an indication for early transplantation in patients with organic acidaemias. We discuss the anaesthetic management and metabolic implications of acidaemia in the first two cases of successfully treated propionic and methylmalonic acidaemia in Italy. A nine and 12 month follow up did not show any further metabolic failure after the procedure, indicating that early liver transplantation improves the quality of life of these patients.
Oestradiol Induced Inhibition of Neuroendocrine Marker Expression in Leydig Cells of Adult Rats
Authors: Ortega HH , Salvetti NR , Baravalle C , Lorente JA , Mira GA
Published: May 2006

Contents

The objectives of this work were to determine the changes in the expression of neuroendocrine markers in Leydig cell by oestradiol treatment, and to determine whether testosterone is able to recover partially the effects of hormonal suppression induced by oestradiol. Adult male rats were injected daily with either 50 μg of oestradiol or oestradiol plus testosterone propionate (25 mg every 3 days) for 15 days. The animals were sacrificed and testicles were dissected and processed by routine histological protocols. FSH and LH serum levels were determined by radioimmunoassay. The visualization of antigens was achieved by the streptavidin‐peroxidase immunohistochemical method. Antibodies against chromogranin A (CrA), S‐100 protein (S‐100), P substance (PS), synaptofisin (SYN), neurofilament protein (NF), gliofibrillary acidic protein (GFAP) and neuron specific enolase (NSE) were used. The mean LH and FSH serum concentrations were consistently suppressed with hormonal treatments. Intermediate filaments (NF and GFAP) showed no difference in their expression. The expression of S‐100, NSE and SYN was significantly lower in both hormone‐treated groups. In oestradiol‐treated rats, the immunoreactivity of CrA and SP decreased significantly but was restored after testosterone supplementation. Although the nature and functions of many of these substances in Leydig cells remain unknown, these results are consistent with the hypothesis that the expression of some neuroendocrine markers is hormonally controlled.
Interaction of carbohydrate metabolism and rat liquid gastric emptying in sustained running
Authors: CHANG FULL‐YOUNG , LU CHING‐LIANG , LEE SHOU‐DONG , DOONG MING‐LUEN , YEH JIUN‐YIH , WANG PAULUS S
Published: May 2006

Background:  Moderate to severe running usually leads to gastrointestinal dysmotility and critical energy exhaustion. It is unknown whether the carbohydrate metabolism of runners can influence gastric emptying (GE). Using a running rat model, the present study explored the impact of exercise/carbohydrate metabolism on liquid GE.

Methods:  Rats were put on the runways of a moving treadmill for 1 h. Trained rats underwent daily running 5 days a week for 4 weeks. Untrained rats were those put on a quiet treadmill to serve as sham exercise. On the motility study day, trained and untrained rats ran for 45 min. After orogastric feeding of radiochromium marker, they resumed running for an additional 15 min and were then killed in order to measure GE. Another group of trained and untrained rats received lactate infusion for 1 h in the quiet condition to measure their GE. The third group of rats received glucose infusion during running to measure GE.

Results:  Running of untrained (P < 0.05) and trained (P < 0.01) rats enhanced GE compared to sham exercise. Running for the untrained rats rather than the trained counterparts had diminished plasma glucose level (P < 0.05). Running also elevated plasma lactate levels for both untrained (P < 0.001) and trained rats (P < 0.01). Lactate infusion delayed GE in untrained (P < 0.01) and trained rats (P < 0.05). Glucose infusion of untrained rats during running was not only to correct hypoglycemia (P < 0.01) but also to restore their enhanced GE (P < 0.01).

Conclusions:  Running‐induced hypoglycemia, rather than lactate accumulation, is one of the essential factors leading to enhanced liquid GE in untrained rats.
Rebound intracranial hypertension after treatment of spontaneous intracranial hypotension
Authors: Tsui H. , Wu S. , Kuo H. , Chen C.
Published: May 2006

Spontaneous intracranial hypotension (SIH) is characterized by orthostatic headache and the cause is usually cerebrospinal fluid leaks in spine level. Most patients with SIH have a benign course. Epidural blood patch (EBP) is the treatment of choice when initial conservative managements are ineffective. We reported a patient with SIH diagnosed by using magnetic resonance imaging and radionuclide cisternography. Acute rebound intracranial hypertension developed after EBP and was successfully treated with intravenous osmotic agent.
Lovastatin‐induced up‐regulation of the BH3‐only protein, Bim, and cell death in glioblastoma cells
Authors: Jiang Zhihong , Zheng Xiao , Lytle Richard A. , Higashikubo Ryuji , Rich Keith M.
Published: May 2006

The mechanism of lovastatin‐induced cell death was examined in three established human glioblastoma cell lines; U87, U251, and U138. Changes in potential modifiers of apoptosis, including Bcl‐2 family proteins and MAP kinase targets after such lovastatin treatment, were evaluated. Lovastatin (5 μm) treatment causes extensive cell death in two of the cell lines, U87 and U251; but only minimal in a third, U138. Lovastatin‐induced death occurs in correlation with significantly increased levels of the BH3‐only protein, Bim. The up‐regulation of Bim levels was directly associated with an increased incidence of apoptosis. Lovastatin treatment in U87 cells results in activation of targets of three major mitogen‐activating protein kinase cascades including Erk1/2, JNK and p38. Changes in levels of Bim, as well as increase phosphorylation of Erk1/2, c‐jun, and p38 are all prevented by co‐incubation of lovastatin and the isoprenylation metabolite, geranylgeranyl pyrophosphate. Inhibition of the MAP kinase pathways failed to block the increased expression of Bim expression or cell death. Further elucidation of the mechanisms of lovastatin‐induced up‐regulation of Bim and apoptosis in glioblastoma cells are important in determining a potential role for lovastatin as a chemotherapy agent.