bluuebunny/crossref_metadata_2025_split huggingface dataset:
Degradation characteristics of blue GaN‐LED chip related to packages
Authors: Kang Jeung‐Mo , Kim Jae‐Wook , Choi Jeong‐Hyeon , Kim Du‐Hyun , Oh Pyung‐Sik , Han Sang‐Kook , Kwon Ho‐Ki 
Published: April 2010

AbstractThis paper reports the degradation characteristics of blue GaN‐LED (Gallium Nitride‐light emitting diode) chip related to various packages. Three types of package have been considered to investigate degradation characteristics in this study. One package is our proposed new concept of metal package by which we can estimate the lifetime of blue LED chip (chip size: 1mm × 1mm) with high accuracy. In the proposed package, components in conventional LED package which may obscure the degradation behaviour of LED chip itself were removed or replaced by other materials or components. And as a control group, two types of commercial packages were used (3W package and low power package). We investigated and analyzed the light‐output degradation and changing of package materials of high‐power blue LED chip packaged with these three types of package to aging time of 5,000 hours. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical characterization of AlGaN/GaN quantum disc structures in single nanowires
Authors: Rigutti L. , Fortuna F. , Tchernycheva M. , De Luna Bugallo A. , Jacopin G. , Julien F. H. , Furtmayr F. , Stutzmann M. , Eickhoff M. 
Published: April 2010

AbstractWe report a systematic study of the luminescence properties of AlxGa1‐xN/GaN single and multi quantum disc structures in single nanowires with Al fraction xAl varying from 0.05 to 1. These quantum structures are situated on the top of GaN nanowires grown in the polar [0001] direction. Nanowires are synthesized by Plasma Assisted Molecular Beam Epitaxy under nitrogen rich growth conditions at a substrate temperature of T = 780 °C on Si (111) substrates. The PL energy of single and multi‐quantum disc systems is explained in terms of Al content in the barriers, band bending at the upper polar surface, and strain relaxation in the heterostructure region (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantification of unintentional doping in non‐polar GaN using scanning capacitance microscopy
Authors: Zhu Tongtong , Kappers Menno J. , Moram Michelle A. , Oliver Rachel A. 
Published: April 2010

AbstractUnintentional doping in non‐polar a ‐plane (11‐20) gallium nitride (GaN) grown on r ‐plane (1‐120) sapphire has been characterized using scanning capacitance microscopy. A conductive interface layer has been observed adjacent to the GaN/sapphire interface, and its average thickness has been quantified and found to increase as the duration of an initial period of three‐dimensional growth is increased. By using a Si doped calibration staircase structure, the conductive interface region is found to contain an average carrier concentration of (2.5 ± 0.3) x 1018 cm‐3. We also observe unintentionally‐doped features extending at 60° from the GaN/sapphire interface. We suggest that these inclined features may be due to impurity incorporation around prismatic stacking faults. The carrier concentration decreases along the inclined feature with distance from the GaN/sapphire interface. In addition, the inclined features are found more frequently in a sample subjected to an additional annealing process, which may provide evidence that the unintentional doping arises from oxygen diffusion from the sapphire substrate. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal caliper widths for propensity‐score matching when estimating differences in means and differences in proportions in observational studies
Authors: Austin Peter C. 
Published: April 2010

AbstractIn a study comparing the effects of two treatments, the propensity score is the probability of assignment to one treatment conditional on a subject's measured baseline covariates. Propensity‐score matching is increasingly being used to estimate the effects of exposures using observational data. In the most common implementation of propensity‐score matching, pairs of treated and untreated subjects are formed whose propensity scores differ by at most a pre‐specified amount (the caliper width). There has been a little research into the optimal caliper width. We conducted an extensive series of Monte Carlo simulations to determine the optimal caliper width for estimating differences in means (for continuous outcomes) and risk differences (for binary outcomes). When estimating differences in means or risk differences, we recommend that researchers match on the logit of the propensity score using calipers of width equal to 0.2 of the standard deviation of the logit of the propensity score. When at least some of the covariates were continuous, then either this value, or one close to it, minimized the mean square error of the resultant estimated treatment effect. It also eliminated at least 98% of the bias in the crude estimator, and it resulted in confidence intervals with approximately the correct coverage rates. Furthermore, the empirical type I error rate was approximately correct. When all of the covariates were binary, then the choice of caliper width had a much smaller impact on the performance of estimation of risk differences and differences in means. Copyright © 2010 John Wiley & Sons, Ltd.
A comparative study on ridge waveguide laser diodes with SiO2 and SiNx passivation layers
Authors: Bengi A. , Jang S. J. , Yeo C. I. , Mammadov T. , Özçelik S. , Lee Y. T. 
Published: April 2010

AbstractIn this study, we have reported the fabrication and device characteristics of metal organic chemical vapor deposition (MOCVD) grown 1.3‐µm InP‐based InGaAsP multiquantum well ridge waveguide laser diodes (LDs) for communication systems. The LD parameters such as threshold current, differential resistivity and output power for SiO2 and SiNx passivation layers have been compared. Fabricated LDs have a threshold current, differential resistivity and output power values of 42 mA, 20 Ω, 9.3 mW and 51 mA, 25 Ω, 6.8 mW for SiO2 and SiNx passivation layers, respectively. The analyses showed that the fabricated LD with SiO2 passivation layer has a better performance than the other one in the view of lower threshold current, differential resistivity and higher output power. Copyright © 2010 John Wiley & Sons, Ltd.
Optical behaviors of thin indium‐containing chalcogenide films
Authors: Petkov P. , Stoilova A. , Nedeva Y. , Petkov E. 
Published: April 2010

AbstractThe optical spectra of thin (GeSe5)100−xInx films, with x from 0 to 20 mol% indium, have been studied with a view to understanding the role of indium on the film behavior. An optical characterization method, based on the transmission and the reflection spectra at normal incidence of uniform, thin films, has been used to obtain the thicknesses and optical constants corresponding to the as‐deposited and annealed samples. The dispersion of the refractive index is discussed in terms of the single‐oscillator Wemple‐Di Domenico model. The absorption edges are described using both the Urbach rule and the ‘nondirect transition’ model proposed by Tauc. The variations in the refractive index, the bandgap, and the oscillation energy of the films after annealing are discussed with respect to rearrangement of the main structure units. Copyright © 2010 John Wiley & Sons, Ltd.
Electronic and optical properties of GIZO thin film grown on SiO2/Si substrates
Authors: Tahir Dahlang , Lee Eun Kyoung , Kwon Hyuk Lan , Kun Oh Suhk , Kang Hee Jae , Heo Sung , Lee Eun Ha , Chung Jae Gwan , Lee Jae Cheol , Tougaard Sven 
Published: April 2010

AbstractThe electronic and optical properties of GaInZnO (GIZO) thin films grown on SiO2/Si by r.f. magnetron sputtering were obtained by means of XPS and reflection electron energy loss spectroscopy (REELS). The optical properties represented by the dielectric function ε, refractive index n, extinction coefficient k and transmission coefficient T of GIZO thin films were obtained from a quantitative analysis of the REELS spectra. When the concentration ratios of Ga:In:Zn in GIZO thin films are 1:1:1, 2:2:1, 3:2:1 and 4:2:1, the bandgap values are 3.2, 3.2, 3.4 and 3.6 eV, respectively. The optical properties were determined from the energy loss of the REELS spectra by using quantitative analysis of electron energy loss spectra (QUEELS)‐ε(k, ω)‐REELS software. The optical properties depend on the Ga concentration, and the transmission in the visible region improved with increasing Ga concentration in GIZO. Copyright © 2010 John Wiley & Sons, Ltd.
Towards a reliable characterisation of oxide layers on pure aluminium using high energy resolution FE‐AES
Authors: Vandendael I. , Hauffman T. , Van Ingelgem Y. , Hubin A. , Terryn H. 
Published: April 2010

AbstractAl2O3 on metallic aluminium is a widely used material of high technological importance. For the local chemical characterisation of these substrates, field‐emission Auger electron spectroscopy (FE‐AES) bears potential thanks to its high lateral resolution. In this study, the O KLL and Al KLL Auger electron spectral lines are recorded with high energy resolution from pure aluminium, thin Al2O3 and thick Al2O3 layers on metallic aluminium. The behaviour of these aluminium oxide layers under electron beam irradiation is investigated.It is demonstrated that, thanks to the high energy resolution used, it is possible to discriminate between the metallic and oxidised aluminium on the basis of the Al0 KL2, 3L2, 3 and Al3+ KL2, 3L2, 3 Auger electron peaks recorded within one and the same spectrum. Oxygen electron‐stimulated desorption is observed for both aluminium oxides. The estimation of the effective cross‐section for the oxygen desorption shows that the thin oxide layer is less stable against this phenomenon than the thick oxide layer. It is shown that when an Al2O3 layer is irradiated with an electron beam, surface charging occurs. These phenomena remain limited thanks to the presence of the underlying metallic aluminium substrate. Finally, it is shown that non‐homogeneities at the surface of the analysed oxides result in significant chemical shifts of the O KLL and Al KLL Auger electron transitions. Copyright © 2010 John Wiley & Sons, Ltd.
Adhesion Properties of Plywood Glue Containing Soybean Meal as an Extender
Authors: Hojilla‐Evangelista Mila P. 
Published: April 2010

AbstractThis study was conducted to evaluate the performance of soybean meal as a protein extender in plywood adhesive intended for sprayline coaters. Ground soybean meal, with 52.8% (dry basis, db) crude protein and 0.9% (db) residual oil, replaced the current industry extender, wheat flour, in the standard glue mix. Substitution was done on the protein content basis. Mixing and adhesion properties of the glue containing soybean meal were compared with those of the industry‐standard glue. The soybean meal‐based glue showed excellent mixing characteristics and its viscosity (1,275 cp) met the recommended value for this type of adhesive. Its wet tensile strength, however, was less than that of the standard glue and below the threshold value of 200 psi considered as an indicator of strong bonding. The soybean meal glue formulation was then modified further by increasing the amount of meal such that the amount of protein present was double that contributed by wheat flour in the original mix. This adjustment resulted in higher wet tensile strength (209 psi), which not only met the threshold value for strong glue bonds, but also equaled that of the standard glue. These results demonstrated that soybean meal is a viable extender in plywood glue for sprayline coaters.
Poor school bonding and delinquency over time: Bidirectional effects and sex differences
Authors: Freidenfelt Liljeberg Jenny , Eklund Jenny M. , Fritz Marie Väfors , af Klinteberg Britt 
Published: April 2010

ABSTRACTThe association between poor school bonding and delinquency has only been partly addressed in earlier research. Using a longitudinal design, the objective of our study was to investigate possible bidirectional effects and sex differences between adolescents’ experienced school bonding and self‐rated delinquency over time. A total of 788 adolescents (353 boys and 435 girls) were investigated by questionnaire at age 14 and 16. Poor school attachment and commitment as well as poor teacher attachment were found to be stronger determinants of delinquency for males than for females. Delinquency predicted poor school commitment for both boys and girls, and poor school attachment for girls, thus indicating bidirectional effects over time and sex differences in some of the bidirectional effects. The study concludes that the delinquency propensity of adolescent boys may be affected by all school bonding dimensions, whereas for girls it is their relationship with their teachers that is of significance.
Validation of the German Version of the Brief Assessment of Cognition in Schizophrenia (BACS) – Preliminary Results
Authors: Sachs G. , Winklbaur B. , Jagsch R. , Keefe R.S.E. 
Published: April 2010

AbstractThe German version of the BACS showed high test-retest reliability. Sensitivity and specificity scores demonstrated good ability to differentiate between patients and controls. The study suggests that the German Version of the BACS is a useful scale to evaluate cognitive functioning.
Obesity and its outcomes among pregnant South African women
Authors: Basu Jayati K. , Jeketera Clara M. , Basu Debashis 
Published: April 2010

AbstractObjectiveTo determine the prevalence of obesity and its effect on maternal and fetal outcomes among pregnant women at the Johannesburg Hospital, South Africa.MethodsA retrospective study of 767 pregnant women divided into BMI groups. Complications such as pregnancy‐induced hypertension (PIH), gestational diabetes mellitus (GDM), urinary tract infection (UTI), preterm labor, preterm rupture of membranes (PROM), induction of labor (IOL), postdates, fetal weight, and fetal outcome were compared among the BMI groups. Seasonal variation in BMI was measured. Descriptive statistics included mean with 95% confidence interval or median with interquartile range. Inferential statistics included t test, χ2 test, analysis of variance (ANOVA), and analysis of covariance.ResultsAmong the study population, 337 (44%) were obese or morbidly obese. The complications of GDM (P < 0.001), UTI (P = 0.002), and failed IOL (P = 0.003) were significantly more common among morbidly obese women. There was no seasonal variation in BMI.ConclusionThe prevalence of obesity in pregnancy was high in South African women and was associated with an increase in complications.
Improving maternal and perinatal health care in the Central Asian Republics
Authors: Borchert Matthias , Bacci Alberta , Baltag Valentina , Hodorogea Stelian , Drife James 
Published: April 2010

AbstractObjectiveTo describe our experience of a complex training intervention to introduce effective perinatal care, evidence‐based medicine, national confidential enquiries into maternal deaths, and facility‐based near‐miss case reviews in the Central Asian Republics.MethodsWe describe our experiences from training sessions and report on findings from data extraction from patient records, patient interviews, discussions with healthcare staff, and observation of health care during our follow‐up visits.ResultsMany outdated practices in perinatal care have been abandoned, and several recommended approaches have been adopted in pilot facilities. Familiarity with the concept of evidence‐based medicine has increased among participants. National confidential enquiries into maternal deaths are being prepared and facility‐based near‐miss case reviews piloted.ConclusionThe experience of the complex training intervention to improve maternal and perinatal health care in the Central Asian Republics is encouraging, but roll‐out will be challenging. The quality of care and the attitudes of healthcare providers will have to be monitored continuously.
Haemotropic Mycoplasmas: What's Their Real Significance in Cats?
Authors: Tasker Séverine 
Published: April 2010

Practical relevance The feline haemotropic mycoplasmas (‘haemoplasmas’) are a group of bacteria that can induce haemolytic anaemia in cats. Mycoplasma haemofelis is the most pathogenic of the species; ‘ Candidatus Mycoplasma haemominutum’ and ‘ Candidatus Mycoplasma turicensis’ are less pathogenic. The natural route of transmission of feline haemoplasma infection has not been confirmed, but fleas are implicated. When disease results, common clinical signs are pallor, lethargy, anorexia, weight loss, depression, dehydration and pyrexia. Treatment with tetracyclines or fluoroquinolones is usually effective at resolving clinical disease, but clearance of infection may not result. Global importance The feline haemoplasmas are found worldwide, although prevalence varies geographically. Patient group Older male non-pedigree cats are believed to be at increased risk of haemoplasma infection, although younger cats are possibly more likely to show clinical disease associated with M haemofelis. Clinical challenges The significance of feline haemoplasma infection is difficult to determine due to the existence of asymptomatic carrier cats and the variable pathogenicity of the haemoplasma species. Polymerase chain reaction (PCR) results should be interpreted in the light of the patient's clinical signs and haematological findings, infecting haemoplasma species and level of haemoplasma DNA present in the blood. Trial antibiotic treatment for haemoplasmosis may be warranted in suspected cases while awaiting PCR results. Evidence base Aspects of feline haemoplasmosis, particularly risk factors, pathogenesis, diagnostic methods and treatment, have been the focus of much recent research. This article draws on the current evidence base with a view to helping clinicians diagnose and manage cases more effectively.
Treatment of Corneal Ulcers: What are the Medical Options?
Authors: Hartley Claudia 
Published: April 2010

Practical relevance Corneal ulcers in cats (ulcerative keratitis) are a common presenting complaint, and are a frequent sequela to feline herpesvirus (FHV-1) infection. In fact, it is fair to assume an FHV-1 aetiology until proven otherwise. In practice, therefore, many cases of corneal ulceration can be treated medically, but treatment can frequently be challenging, with the need to tailor therapy carefully to the type of ulcer, the individual cat and its temperament.Patient group All age groups and breeds can suffer with ulcerative keratitis although some breeds are over-represented for some types of corneal ulceration.Evidence base The scientific literature on feline ulcerative keratitis is extensive, particularly that related to FHV-1 infection. This article reviews the medical treatment options for corneal ulceration in cats with reference to the current evidence base.
Treatment of Corneal Ulcers: When is Surgery Indicated?
Authors: Hartley Claudia 
Published: April 2010

Practical relevance While corneal ulcers in cats frequently arise secondarily to feline herpesvirus (FHV-1) infection, and thus medical therapy is often indicated, other causes include trauma, eyelid abnormalities (agenesis, entropion, dermoids and neoplasia), tear film abnormalities and neurological deficiencies (trigeminal nerve paralysis or facial nerve paralysis). In some such cases, surgery is required. Treatment always needs to be tailored carefully according to the depth and progression of the ulcer, any concurrent ophthalmic disease, the patient's general health and demeanour, and owner compliance and financial circumstances.Patient group All age groups and breeds can suffer with ulcerative keratitis although some breeds are over-represented for some types of corneal ulceration.Evidence base The scientific literature on feline ulcerative keratitis is extensive. This article reviews the surgical indications for corneal ulceration in cats with reference to the current evidence base.
Successful Treatment of Acromegaly in a Diabetic Cat with Transsphenoidal Hypophysectomy
Authors: Meij Björn P , Auriemma Edoardo , Grinwis Guy , Buijtels Jenny J C W M , Kooistra Hans S 
Published: April 2010

Patient and surgical treatment An 11-year-old, castrated male cat was referred for insulin-resistant diabetes mellitus. It had a ravenous appetite, increased body weight, polyuria/polydipsia and a dull hair coat. The cat was receiving 25 IU insulin four times daily but blood glucose concentrations remained elevated. Plasma concentrations of growth hormone (GH) (51 μug/l, reference range 0.8–7.2 μg/l) and insulin-like growth factor 1 (IGF-1) (3871 μg/l, reference range 39–590 μg/l) were highly elevated, whereas those of alpha-melanocyte-stimulating hormone, adrenocorticotropic hormone and Cortisol were normal. Computed tomography revealed a thick palatum molle and an enlarged pituitary gland, indicating a pituitary neoplasm. Microsurgical transsphenoidal hypophysectomy was performed and microscopic examination of the surgical specimen revealed an acidophilic, infiltrative pituitary adenoma that showed positive immunostaining for GH. Outcome The clinical signs resolved and 3 weeks after surgery the cat no longer required insulin administration. One year after hypophysectomy the plasma concentrations of GH and IGF-1 were 2.4 μg/l and 113 μg/l, respectively. Practical relevance This is the first report detailing transsphenoidal hypophysectomy as a feasible and effective treatment for feline acromegaly due to a pituitary somatotroph adenoma. Moreover, in this patient, concurrent insulin-resistant diabetes mellitus resolved completely. The surgery is discussed in the context of human and other feline therapies for acromegaly.
Synovial Osteochondroma Involving the Elbow of a Cat
Authors: Tan Chris , Allan Graeme S , Barfield Dominic , Krockenberger Mark B , Howlett Rolfe , Malik Richard 
Published: April 2010

Clinical presentation A 12-year-old spayed domestic crossbred cat presented because she would not walk down stairs. A firm swelling on the medial aspect of the elbow was detected during physical examination. The lesion was not hot or painful on palpation and the lameness was mild, but the elbow had a reduced range of motion compared with the contralateral limb. Diagnosis and treatment Plain radiographs, physical findings, the appearance of the lesion at surgery and histopathological examination of biopsy specimens suggested the mass was a synovial osteochondroma arising from synovial membrane near the medial portion of the elbow joint. Resection of the lesion improved the cat's mobility and overall clinical status. At the time of writing, the cat continued to do well 18 months following surgery and was receiving standard doses of meloxicam for the concurrent elbow osteoarthritis. Practical relevance Practitioners should be alert to the possibility of this benign entity. Misdiagnosis as a chondrosarcoma, for example, might conceivably lead to radical and unnecessary amputation.
Congenital Large Intestinal Hypoganglionosis in a Domestic Shorthair Kitten
Authors: Roe Kirsty A M , Syme Harriet M , Brooks Harriet W 
Published: April 2010

Clinical presentation and investigations An 11-week-old female domestic shorthair kitten presented with a history of constipation since weaning. Abdominal distension was noted on physical examination and abdominal radiographs revealed a large volume of faeces in the descending and transverse colon. Colonoscopy was unremarkable and euthanasia was performed at the owners' request.Diagnosis The histological diagnosis of large intestinal hypoganglionosis was made post mortem.Significance This appears to be the first reported case of congenital hypoganglionosis in a kitten with histopathological confirmation of the diagnosis. It may potentially be a more common cause of constipation in kittens and young cats than has previously been suspected.