bluuebunny/crossref_metadata_2025 huggingface dataset:
The CABG Surgery Volume–Outcome Relationship: Temporal Trends and Selection Effects in California, 1998–2004
Authors: Marcin James P. , Li Zhongmin , Kravitz Richard L. , Dai Jian J. , Rocke David M. , Romano Patrick S.
Published: June 2007

Objective. To investigate the temporal trends in the volume–outcome relationship in coronary artery bypass graft (CABG) surgery in California from 1998 to 2004, and to assess the selection effects on this relationship by using data from periods of voluntary and mandatory hospital reporting.

Data Sources. We used patient‐level clinical data collected for the California CABG Mortality Reporting Program (CCMRP, a voluntary reporting program with between 68 and 81 hospitals) from 1998 to 2002 and the California CABG Outcomes Reporting Program (CCORP, a mandatory reporting program with 121 and 120 hospitals) from 2003 to 2004.

Study Design. The patient was the primary unit of analysis, and in‐hospital mortality was the primary outcome. We used hierarchical logistic regression models (generalized linear mixed models) to assess the association of hospital annual volume with hospital mortality while controlling for detailed patient‐level covariates in each of the 7 years.

Data Collection Methods. All data were systematically collected, reviewed for accuracy, and validated by the State of California's Office of Statewide Health Planning and Development (OSHPD).

Principal Findings. We found that during the period of voluntary hospital reporting (1998–2002), with the exception of 1998, higher volume hospitals had significantly lower risk‐adjusted in‐hospital mortality rates, on average, than lower volume hospitals (1998 odds ratio [OR] per 100 operations performed=0.962, 95 percent confidence interval [CI]: 0.912–1.015; 1999 OR=0.955, 95 percent CI: 0.920–0.991; 2000 OR=0.942, 95 percent CI: 0.897–0.989; 2001 OR=0.935, 95 percent CI: 0.887–0.986; 2002 OR=0.946, 95 percent CI: 0.899–0.997). We also found that in the period of mandatory reporting (2003 and 2004) there was no volume–outcome relationship (2003 OR=0.997, 95 percent CI: 0.939–1.058; 2004 OR=0.984, 95 percent CI: 0.915–1.058) and that this lack of association was not due to a reporting bias from the addition of data from hospitals that did not originally contribute during the voluntary program.

Conclusions. In California, where no state regulations support regionalization of CABG surgeries, a weak volume–outcome relationship was present from 1998 to 2002, but was absent in 2003 and 2004. The disappearance of the volume–outcome association was temporally related to the implementation of a statewide mandatory CABG surgery reporting program.
Three‐dimensional ultrasound imaging of the levator hiatus in late pregnancy and associations with delivery outcomes
Authors: LANZARONE Valeria , DIETZ Hans Peter
Published: June 2007

Objective:  To determine the correlations between dimensions of the levator hiatus in late pregnant nulliparous women, mode of delivery and length of second stage.

Methods:  This was a prospective observational pilot study of 61 nulliparous women seen and examined between 36 and 40 weeks of pregnancy. A translabial ultrasound examination was undertaken, and three‐dimensional volumes comprising the levator hiatus were recorded at rest, during a pelvic floor muscle contraction and on Valsalva. The volumes were analysed in a blinded fashion using proprietary software to determine linear dimensions and hiatal area. Information regarding delivery outcomes and course of labour was obtained from the obstetric database. Statistical analysis was undertaken for correlations between hiatal dimensions and labour outcomes.

Results:  No consistent correlations were found between levator dimensions and delivery mode. However, an inverse correlation was demonstrated between the area of the hiatus, particularly on pelvic floor contraction, and length of total second stage.

Conclusions:  Levator hiatal dimensions are associated with the length of the second stage of labour. Although the numbers were small, our findings suggest that the effect of pelvic floor structures on progress in labour is worth further study.
The role of continuous glucose monitoring in clinical decision‐making in diabetes in pregnancy
Authors: McLACHLAN Kylie , JENKINS Alicia , O’NEAL David
Published: June 2007

Background:  The continuous glucose monitoring system (CGMS) is a novel tool to assess 24‐h glucose fluctuations. In pregnancies complicated by diabetes, where excellent glucose control is desired to improve maternal and fetal outcomes, CGMS may have a role in fine‐tuning management.

Aims:  To assess the usefulness of CGMS in pregnant women with diabetes for medical decision‐making and to evaluate patient tolerability and perception of usefulness.

Methods:  Pregnant women with diabetes at the Werribee Mercy Hospital were offered CGMS in the setting of their standard diabetes care. Treating clinicians were asked if the CGMS altered management decisions from those based on conventional glucose monitoring. The accuracy of the CGMS was assessed by comparison with the patients’ finger‐prick glucose readings. Patients completed a feedback questionnaire after having the CGMS and viewing their results.

Results:  CGMS traces (n = 68) were obtained in 55 pregnant women – 37 with gestational diabetes, ten with type 2 and eight with type 1 diabetes. Forty‐two of 68 (62%) traces were assessed as providing additional information which altered clinical management decisions. This included showing undetected postprandial hyperglycaemia and overnight hypoglycaemia. Subject feedback was generally positive, with 37 of 48 (77%) respondents reporting that the benefits of the CGMS outweighed the inconvenience.

Conclusion:  CGMS is a well‐tolerated clinically useful tool in the management of gestational diabetes and pre‐existing diabetes in pregnancy.
The impact of chronic vulval pain on quality of life and psychosocial well‐being
Authors: SARGEANT Hilary A. , O’CALLAGHAN Frances V.
Published: June 2007

Background: Chronic or recurrent pain associated with the female reproductive system is not well understood and has been neglected in research, despite it being a costly health problem.

Aims: The present research investigated the psychosocial impact of vulval pain on health‐related quality of life, sexual well‐being, and relationship satisfaction among Australian women.

Methods: Between June and December 2004, Australian women with and without vulval pain completed a questionnaire containing a range of well‐validated self‐report measures. Questionnaires were returned by 51 women aged between 19 and 68 years with vulval pain and 46 women aged between 21 and 65 years without vulval pain.

Results: Similar to previous research, Australian women with vulval pain reported significantly worse health‐related quality of life, higher levels of distress related to sexual activities, and lower levels of happiness in couple relationships than those without pain.

Conclusions: These results highlight serious psychosocial implications for women experiencing chronic vulval pain. Understanding the impact that vulval pain has on women may assist in developing appropriate psychosocial interventions that may improve quality of life.
Interacting Effects of Climate Change, Landscape Conversion, and Harvest on Carnivore Populations at the Range Margin: Marten and Lynx in the Northern Appalachians
Authors: CARROLL CARLOS
Published: June 2007

Abstract:  Assessing the effects of climate change on threatened species requires moving beyond simple bioclimatic models to models that incorporate interactions among climatic trends, landscape change, environmental stochasticity, and species life history. Populations of marten (Martes americana) and lynx (Lynx canadensis) in southeastern Canada and the northeastern United States represent peninsular extensions of boreal ranges and illustrate the potential impact of these threats on semi‐isolated populations at the range margin. Decreased snowfall may affect marten and lynx through decreased prey vulnerability and decreased competitive advantage over sympatric carnivores. I used a spatially explicit population model to assess potential effects of predicted changes in snowfall by 2055 on regional marten and lynx populations. The models' habitat rankings were derived from previous static models that correlated regional distribution with snowfall and vegetation data. Trapping scenarios were parameterized as a 10% proportional decrease in survival, and logging scenarios were parameterized as a 10% decrease in the extent of older coniferous or mixed forest. Both species showed stronger declines in the simulations due to climate change than to overexploitation or logging. Marten populations declined 40% because of climate change, 16% because of logging, and 30% because of trapping. Lynx populations declined 59% because of climate change, 36% because of trapping, and 20% in scenarios evaluating the effects of population cycles. Climate change interacted with logging in its effects on the marten and with trapping in its effects on the lynx, increasing overall vulnerability. For both species larger lowland populations were vulnerable to climate change, which suggests that contraction may occur in the core of their current regional range as well as among smaller peripheral populations. Despite their greater data requirements compared with bioclimatic models, mesoscale spatial viability models are important tools for generating more biologically realistic hypotheses regarding biotic response to climate change.
The Clinical, Psychosocial, and Socioeconomic Concerns of Urban Youth Living With Diabetes
Authors: Gee Leslie , Smith Tracie L. , Solomon Marla , Quinn Michael T. , Lipton Rebecca B.
Published: June 2007

ABSTRACT
Objective: Young people with chronic diseases face the challenge of moving from the pediatric to the adult health care environment, in addition to the normal hurdles of young adulthood. To most effectively help them through this process, we must first understand their perspective.

Design: Qualitative study of the social and emotional impact of having diabetes.

Sample: Young adults (n=23), aged 19–26, who had been living with diabetes for a median of 12 years (range 4–19) were contacted; all but one were from underserved ethnic minorities.

Measurements: Semistructured telephone interviews were conducted, transcribed, and coded.

Results: Having diabetes profoundly affected the life choices and expectations of these young people; their feelings and attitudes evolved over time. Financial and insurance concerns were key, because managing diabetes care on one's own as an adult was a major challenge. Most young people reported that family, friends, and coworkers were sources of support, but that disclosure of their diabetes was problematic.

Conclusions: Offering emotional and practical support to young adults coping with diabetes is key to ensuring adequate medical management as they move into the adult system and assume full responsibility for their health.
Cigarette Smoking, Socioeconomic Status, and Psychosocial Factors: Examining a Conceptual Framework
Authors: Harwood Gretchen A. , Salsberry Pamela , Ferketich Amy K. , Wewers Mary Ellen
Published: June 2007

ABSTRACTInequalities in cigarette smoking prevalence exist, with smokers more likely to be poor and less educated. Higher socioeconomic status (SES) is associated with higher quit rates. The overall relationship between low SES and poor health, as measured by morbidity and mortality, is well established. However, research indicates that inequalities in health are not explained by SES alone; other variables, such as psychosocial factors, may play a significant role. Williams has developed a conceptual framework to examine relationships among SES, psychosocial factors, and medical care related to health outcomes. According to Williams, the interrelationships among these factors have yet to be determined. As such, the pathways among the variables within psychosocial factors are explored and the authors discuss application to public health nursing practice and areas for future research. Further understanding of these relationships in the context of smoking may inform prevention and cessation strategies.
A Probable Causative Factor for an Old Problem: Selenium and Glutathione Peroxidase Appear to Play Important Roles in Epilepsy Pathogenesis
Authors: Ashrafi Mahmoud Reza , Shams Sedigheh , Nouri Mehrnaz , Mohseni Meysam , Shabanian Reza , Yekaninejad Mir Saeed , Chegini Nastaran , Khodadad Ahmad , Safaralizadeh Reza
Published: June 2007

Summary:  Purpose: Only recently has it become known that oxidative stress and generation of reactive oxygen species are the cause and the consequence of epileptic seizures. Due to the protective role of selenium (Se) and selenoproteins against oxidative damage and the ability to promote neuronal cell survival, we compared serum selenium level and red blood cell Glutathione peroxidase activity (RBC GPx) between epileptic and healthy children.

Methods: In a case control study, 53 epileptic children were compared with 57 healthy children in the same age and community of residence. Serum Se and RBC GPx activity were measured with an atomic absorption spectrophotometry and Cayman standard glutathione assay kit, respectively.

Results: The mean (±standard deviation) of serum Se was 72.90 μg/L (±22.20) and 86.00 μg/L (±15.00) in patient and control groups, respectively. For RBC GPx activity the mean (±standard deviation) was 440.57 nmol/min/ml (±264.00) and 801.00 nmol/min/ml (±267.00) in patient and control groups, respectively. Statistical analysis showed a significant lower means of serum Se and RBC GPx activity in patient group compared to that of healthy control group (p < 0.001).

Conclusion: Lower serum Se and RBC GPx activity in epileptic patients compared to healthy children may support the proposed crucial role of Se and GPx activity in the pathogenesis of epilepsy. However, RBC GPx activity in the case of selenium deficiency could not be a sensitive and specific indicator of Se status in serum that led us to supplant Se measurement with RBC GPx activity.
Autism Spectrum Disorders in Children with Seizures in the First Year of Life—A Population‐Based Study
Authors: Saemundsen Evald , Ludvigsson Petur , Hilmarsdottir Ingibjorg , Rafnsson Vilhjalmur
Published: June 2007

Summary: Purpose:To describe autistic spectrum disorders (ASDs) in a cohort of children with history of unprovoked seizures other than infantile spasms in the first year of life.

Methods:The source of data was computer records from all the three pediatric departments in Iceland. Children diagnosed 1982–2000 with unprovoked seizures with onset between 28 days and 12 months of age (N = 102) were invited to participate in a study. Children with known developmental disorders and those whose parents had concerns regarding their child's development or behavior were investigated for possible ASD. Parents were asked to complete the Social Communication Questionnaire and children scoring 10 points or higher were further examined with the Autism Diagnostic Interview‐Revised and observational measures.

Results:Eighty‐four children (82.4%), 28 boys and 56 girls, participated in the study and 36.9% (31/84) were investigated for possible ASD. Twenty‐four (28.6%) had at least one neurodevelopmental disorder, 14.3% had mental retardation (MR), and six (7.1%) were diagnosed with ASD, all of whom also had MR and three of whom had congenital brain abnormalities.

Conclusion:These results suggest that the estimated prevalence of ASD is higher in children with history of seizure in the first year of life than it is in the general population. There are indications that support the view that children with ASD and history of seizure in the first year of life have higher prevalence of congenital brain abnormalities and are more often female, than other children with ASD.
The Beneficial Effect of Spinal Cord Stimulation in a Patient With Severe Cerebral Ischemia and Upper Extremity Ischemic Pain
Authors: De Andrés Jose , Tatay Jose , Revert Amparo , Valía J. C. , Villanueva V.
Published: June 2007

Abstract:  Spinal cord stimulation (SCS) is used in the treatment of chronic pain, ischemia because of obstructive arterial disease, and anginal pain. Recently, a number of studies have described the effects of the high cervical SCS, including increased cerebral blood flow, although the underlying mechanisms are unknown.

This case report describes a patient with a severe complex ischemic condition affecting both cerebral and upper limb blood flow with an associated complex regional pain syndrome in upper limb. While all previous clinical treatments proved ineffective, cervical SCS afforded satisfactory results. Possible mechanisms underlying the cervical SCS effect are discussed.
Burning Mouth Syndrome: Will Better Understanding Yield Better Management?
Authors: Maltsman‐Tseikhin Alexander , Moricca Paolo , Niv David
Published: June 2007

Abstract:  “Burning mouth syndrome” (BMS) refers to a chronic orofacial pain disorder usually unaccompanied by mucosal lesions or other clinical signs of organic disease. BMS is typically characterized by a continuous, spontaneous, and often intense burning sensation as if the mouth or tongue were scalded or on fire.

Burning mouth syndrome is a relatively common condition. The estimated prevalence of BMS reported in recent studies ranges between 0.7 and 4.6% of the general population. About 1.3 million American adults, mostly women in the postmenopausal period, are afflicted with BMS. The etiology of this disorder is poorly understood even though new evidence for a possible neuropathic pathogenesis of idiopathic BMS is emerging.

Burning mouth syndrome may present as an idiopathic condition (primary BMS type) distinct from the symptom of oral burning that can potentially arise from various local or systemic abnormalities (secondary BMS type), including nutritional deficiencies, hormonal changes associated with menopause, local oral infections, denture‐related lesions, xerostomia, hypersensitivity reactions, medications, and systemic diseases including diabetes mellitus. In more than a third of patients, multiple, concurrent causes of BMS may be identified. It is important to note that the diagnosis of BMS should be established only after all other possible causes have been ruled out. Professional delay in diagnosing, referring, and appropriately managing of BMS patients occurs frequently. Treatment should be tailored to each patient and it is recommended to practice the treatment in a multidisciplinary facility.

This article discusses our current understanding of the etiology and pathogenesis of BMS. The authors have tried to emphasize new pharmacological approaches to manage this challenging disorder.
Frequent plateletpheresis does not clinically significantly decrease platelet counts in donors
Authors: Katz Louis , Palmer Kim , McDonnell Emily , Kabat Andy
Published: June 2007

BACKGROUND: In October 2005, the US Food and Drug Administration (FDA) issued draft guidance on collecting platelets (PLTs) by automated methods. The FDA proposed limiting collections to 24 components, rather than 24 procedures, annually with up to 3 components per procedure. The rationale was from literature suggesting frequent PLT collection resulted in significant declines in donor PLT counts. Additional requirements for minimal interdonation intervals were proposed.

STUDY DESIGN AND METHODS: Plateletpheresis records at a regional blood center with predonation PLT counts were used to assess the impact of the restriction on PLT collections. They were reviewed to demonstrate the effects of collection frequency, number of products collected, and interdonation interval on donor PLT counts. Total protein and albumin levels were compared in a subset of 24‐times‐per‐year PLT donors and control whole‐blood donors.

RESULTS: A limit of 24 components would require replacement of approximately 20 percent of the donor base to recover lost components. No clinically important decrease in PLT counts before donation was seen in donors donating multiple PLT components up to 24 times per year, regardless of interdonation interval. No frequent donor was deferred for a PLT count less than 150 × 109 per L. Short interdonation intervals were associated with statistically but not clinically important decreases in PLT counts. Protein levels were not distinguishable between PLT donors and controls.

CONCLUSION: The proposed restrictions are not required to prevent thrombocytopenia in frequent PLT donors and would adversely impact the supply of apheresis PLTs. Protein levels are maintained in these high‐frequency donors.
QT Peak Prolongation Is Not Associated with Left Ventricular Hypertrophy in Teenage Professional Football Players
Authors: Alchaghouri Samir , Wong Kenneth Y.K. , Perry Raphael A. , Ramsdale David R. , Somauroo John D. , Pyatt Jason R.
Published: June 2007

Objective: QT peak prolongation is associated with left ventricular hypertrophy (LVH) in patients with hypertension. This study tests the hypothesis that QT peak prolongation correlates with LV mass index in apparently healthy young football players.

Methods: QT peak and other ECG criteria for LVH were assessed in 117 male professional footballers (mean age 16.4 years ± SD 0.76). Their left ventricular mass index (LVMI) was assessed by transthoracic echocardiography. Heart rate‐corrected QT peak (QTpc) interval was measured in lead I using Bazett's formula. Spearman (2‐tailed) test and UNIANOVA was used to assess if there were correlations between QT peak and the various echocardiographic and ECG indices of LVH.

Results: Echocardiographic LVH, defined as LVMI ≥ 134 g/m2, was seen in 79 (70.5%) subjects. ECG‐defined LVH was present in 54 (50 %) players by Sokolow‐Lyon criteria, in 19 (16 %) players by Romhilt Score, in 5 (4 %) players by Cornell voltage criteria, and in 7 (6 %) players by Cornell product >2436 mm ms. There was no correlation between QT peak (QTpc) and LVMI on echocardiography (Spearman r = 0.058, 2‐tailed P = 0.54). In addition, there was no relation between LVH and QTpc of lead I using any of the following ECG criteria: Sokolow‐Lyon (P = 0.6), Romhilt (P = 0.3), Cornell voltage (P = 0.8), or Cornell product (P = 0.6).

Conclusion: QT peak interval, which is associated with pathological LVH in hypertensive patients and is a measure of risk of cardiac death, does not correlate with LVH characterized by myocyte hypertrophy in young apparently healthy professional footballers.
Prognostic Significance of PVCs and Resting Heart Rate
Authors: Engel Gregory , Cho Shaun , Ghayoumi Afshin , Yamazaki Takuya , Chun Sung , Fearon William F. , Froelicher Victor F.
Published: June 2007

Background: We sought to evaluate the prognostic significance of premature ventricular contractions (PVCs) on a routine electrocardiogram (ECG) and to evaluate the relationship between heart rate and PVCs.

Methods: Computerized 12‐lead ECGs of 45,402 veterans were analyzed. Vital status was available through the California Health Department Service.

Results: There were 1731 patients with PVCs (3.8%). Compared to patients without PVCs, those with PVCs had significantly higher all‐cause (39% vs 22%, P < 0.001) and cardiovascular mortality (20% vs 8%, P < 0.001). PVCs remain a significant predictor even after adjustment for age and other ECG abnormalities. The presence of multiple PVCs or complex morphologies did not add significant additional prognostic information. Those patients with PVCs had a significantly higher heart rate than those without PVCs (mean ± SD: 78.6 ± 15 vs 73.5 ± 16 bpm, P < 0.001). When patients were divided into groups by heart rate (<60, 60–79, 80–99 and >100 bpm) and by the presence or absence of PVCs, mortality increased progressively with heart rate and doubled with the presence of PVCs. Using regression analysis, heart rate was demonstrated to be an independent and significant predictor of PVCs.

Conclusions: PVCs on a resting ECG are a significant and independent predictor of all‐cause and cardiovascular mortality. Increased heart rate predicts mortality in patients with and without PVCs and the combination dramatically increases mortality. These findings together with the demonstrated independent association of heart rate with PVCs suggest that a hyperadrenergic state is present in patients with PVCs and that it likely contributes to their adverse prognosis.
Preliminary Observations on the Effect of Amitriptyline Treatment in Preventing Syncope Recurrence in Patients with Vasovagel Syncope
Authors: Barış Kaya Ergün , Abalı Gülcan , Aytemir Kudret , Köse Sedat , Kocabaş Uğur , Tokgözoğlu Lale , Kabakçı Giray , Amasyalı Basri , Özkutlu Hilmi , Nazlı Nasıh , Oto Ali
Published: June 2007

Purpose: Vasovagal syncope is a common and challenging problem that may result in injury and causes susbstantial anxiety among patients and their relatives. However, treatment of vasovagal syncope with standard pharmacologic approaches is not satisfactory. The aim of this study is to investigate the effect of amitriptyline, a tricyclic antidepressant drug, by using its anticholinergic effects in preventing syncopal episodes in patients with vasovagal syncope.

Methods: In this study, 74 patients (mean age 24 ± 1.9 years, 26 male) with a history of recurrent syncope and baseline positive head‐up tilt table test (syncope or presyncope) were included. Oral amitriptyline treatment was given to all patients, with a starting dose of 10 mg once a day. Head‐up tilt table test was performed in all patients 4 weeks after the treatment started. Patients were followed up clinically for 6 months.

Results: After 4 weeks, during head‐up tilt table test in 69 patients (93%), syncope or presyncope was not seen and test was assumed as negative. At the end of the 6th month, 67 patients (91%) were free of symptoms. Only two patients (0.3%) did not tolerate amitriptyline due to side effects.

Conclusions: Oral amitriptyline can be used in the prevention of recurrent episodes of vasovagal syncope safely. However, randomized controlled studies are essential to assess the real effectiveness of this therapy.
Effective Permeability of NiZnCo Ferrite Granular Thin Films
Authors: Shen Xiang , Gong Rongzhou , Feng Zekun , Nie Yan , Li Haifeng , Nie Jianhua
Published: June 2007

Spinel NiZnCo ferrite granular films 1.5 μm in thickness were prepared on glass substrates by the spray plating method at 90°C with a bias magnetic field of 300 Oe. The soft magnetic film exhibited large saturation magnetization of 270 kA/m and high resistivity of 127Ω cm. The coercivity and in‐plane anisotropy field took small values of 8.7 and 20 Oe. The exact magnetization precessional equation under the weak alternating field was applied to construct a calculation model of the effective permeability excited by an incident field parallel to the film plane. Comparisons of calculated results with experimental ones were in agreement on magnitude. The disagreement between theory and experiment was attributed to a large damping coefficient of the ferrite film. A static permeability μ′ of around 89 and very high resonance frequency of 2.1 GHz were achieved. The value of magnetic loss μ″ was above 15 even in a wide frequency range between 1 and 3.5 GHz.
Interdiffusion Between Ti3SiC2–Ti3GeC2 and Ti2AlC–Nb2AlC Diffusion Couples
Authors: Ganguly Adrish , Barsoum Michel W. , Doherty Roger D.
Published: June 2007

In this work, we report on the interdiffusion of Ge and Si in Ti3SiC2 and Ti3GeC2, as well as that of Nb and Ti in Ti2AlC and Nb2AlC. The interdiffusion coefficient, Dint, measured by analyzing the diffusion profiles of Si and Ge obtained when Ti3SiC2–Ti3GeC2 diffusion couples are annealed in the 1473–1773 K temperature range at the Matano interface composition (≈Ti3Ge0.5Si0.5C2), was found to be given by

image

D
int increased with increasing Ge composition. At the highest temperatures, diffusion was halted after a short time, apparently by the formation of a diffusion barrier of TiC. Similarly, the interdiffusion of Ti and Nb in Ti2AlC–Nb2AlC couples was measured in the 1723–1873 K temperature range. The Dint for the Matano interface composition, viz. ≈(Ti0.5,Nb0.5)2AlC, was found to be given by

image

At 1773 K, the diffusivity of the transition metal atoms was ≈7 times smaller than those of the Si and Ge atoms, suggesting that the former are better bound in the structure than the latter.
New Insights of the Glycine‐Nitrate Process For the Synthesis of Nano‐Crystalline 8YSZ
Authors: Valefi Mahdiyar , Falamaki Cavus , Ebadzadeh Touraj , Hashjin Mehran Solati
Published: June 2007

Nano‐crystalline 8YSZ was synthesized by the glycine‐nitrate process in a muffle furnace using zirconyl nitrate and yttrium nitrate as sources of oxidants. The effect of changing the elemental stoichiometric coefficient over a wide range (0.756–1.605) on the product characteristics (crystallite size, percent unreacted, surface area) has been investigated. It is demonstrated that the combustion reaction proceeds most efficiently in the fuel‐lean region. A novel and simple mathematical model is presented that allows to evaluate the thickness of the sheet‐like particles of the foamy final product based on BET data. The calculated thickness values are in good agreement with the experimental data. For the first time, the effect of using ammonium nitrate as a combustion aid for the stoichiometric precursor composition has been studied. The optimum amount of combustion aid addition has been determined.
Grain Growth Control in NaNbO3–SrTiO3 Ceramics by Mechanosynthesis and Spark Plasma Sintering
Authors: Hungría Teresa , Algueró Miguel , Castro Alicia
Published: June 2007

The combination of non‐conventional methods of synthesis (mechanosynthesis) and sintering (spark plasma sintering, SPS) has been used for the first time to process dense, fine‐grained ceramics of the (1−x)NaNbO3–xSrTiO3 system. Dielectric properties have been measured across main phase transitions in the system for the submicrometer‐structured ceramic materials processed by SPS, and are comparable with those of ceramics prepared by conventional sintering. This approach thus allows grain growth to be controlled while retaining properties, and provides the possibility of processing ceramics of alkaline niobate‐based perovskite solid solutions with a homogeneous, fine‐grained microstructure and good functionality.
Preparation, Hardness, and Fracture Toughness of Tantalum Oxynitride Ceramics
Authors: Matizamhuka Wallace R. , Herrmann Mathias , Sigalas Iakovos , Sempf Kerstin
Published: June 2007

Tantalum oxynitride powder with a baddeleyite crystal structure was synthesized and densified by hot pressing in Ar and under high pressure using a belt‐type high‐pressure apparatus. The tantalum oxynitride powder could not be densified completely under hot‐pressing conditions at 1400°C. The use of high pressure resulted in dense materials. The samples showed a hardness of 16–17 GPa and a fracture toughness of 3–4 MPa·m1/2. The hardness is higher compared with that of ZrO2 and HfO2 ceramics. The fracture toughness corresponds to the value of fully stabilized ZrO2 due to the absence of any transformation toughening mechanism.
Cesium Release From Tungstate and Titanate Waste Form Materials in Simulated Canister Corrosion Product‐Containing Solutions
Authors: Luca Vittorio , Zhang Yingjie , Drabarek Elizabeth , Chronis Harriet
Published: June 2007

The leaching of two potential 137Cs waste form ceramics (Cs‐containing hexagonal tungsten bronze (HTB) and hollandite) has been investigated in Fe(NO3)3 solutions of increasing concentration at 150°C over a period of 4 days. These ceramics contain within their structures reduced Mo5+/W5+ and Ti3+ species for the HTB and hollandite, respectively, which therefore might render them susceptible to oxidation‐induced leaching. Elucidation of the extent and the mechanism of leaching of the Cs from these ceramics in the REDOX active iron nitrate medium has been investigated. Cesium (Cs) leached severely from both the Cs‐loaded HTB and hollandite materials in iron nitrate solutions with virtually all of the immobilized Cs being extracted from both waste form materials in a period of 4 days at 150°C. In the case of hollandite, conversion to ilmenite and hematite was observed at low concentrations and was virtually complete in 0.5 mol/L Fe(NO3)3 over 4 days. In the case of the HTB, all of the Cs was extracted presumably by an ion‐exchange mechanism because the structure of this oxide remained intact and iron was found in the composition. Iron oxide with a hematite structure was also easily observed in the reacted sample at high solution iron concentrations. It is shown that the leach resistance of the Cs‐containing HTB can be improved by substitution of up to 20% Ti for W.
Infant Death Scene Investigation and the Assessment of Potential Risk Factors for Asphyxia: A Review of 209 Sudden Unexpected Infant Deaths
Authors: Pasquale‐Styles Melissa A. , Tackitt Patricia L. , Schmidt Carl J.
Published: June 2007

Abstract:  At the Wayne County Medical Examiner Office (WCMEO) in Detroit, Michigan, from 2001 to 2004, thorough scene investigations were performed on 209 sudden and unexpected infant deaths, ages 3 days to 12 months. The 209 cases were reviewed to assess the position of the infant at the time of discovery and identify potential risk factors for asphyxia including bed sharing, witnessed overlay, wedging, strangulation, prone position, obstruction of the nose and mouth, coverage of the head by bedding and sleeping on a couch. Overall, one or more potential risk factors were identified in 178 of 209 cases (85.2%). The increasing awareness of infant positions at death has led to a dramatic reduction in the diagnosis of sudden infant death syndrome at the WCMEO. This study suggests that asphyxia plays a greater role in many sudden infant deaths than has been historically attributed to it.
Resolving Paternity Relationships Using X‐Chromosome STRs and Bayesian Networks
Authors: Hatsch Didier , Keyser Christine , Hienne Rémi , Bertrand Ludes
Published: June 2007

Abstract:  X‐chromosomal short tandem repeats (X‐STRs) are very useful in complex paternity cases because they are inherited by male and female offspring in different ways. They complement autosomal STRs (as‐STRs) allowing higher paternity probabilities to be attained. These probabilities are expressed in a likelihood ratio (LR). The formulae needed to calculate LR depend on the genotype combinations of suspected pedigrees. LR can also be obtained by the use of Bayesian networks (BNs). These are graphical representations of real situations that can be used to easily calculate complex probabilities. In the present work, two BNs are presented, which are designed to derive LRs for half‐sisters/half‐sisters and mother/daughter/paternal grandmother relationships. These networks were validated against known formulae and show themselves to be useful in other suspect pedigree situations than those for which they were developed. The BNs were applied in two paternity cases. The application of the mother/daughter/paternal grandmother BN highlighted the complementary value of X‐STRs to as‐STRs. The same case evaluated without the mother underlined that missing information tends to be conservative if the alleged father is the biological father and otherwise nonconservative. The half‐sisters case shows a limitation of statistical interpretations in regard to high allelic frequencies.
Efficiency Evaluation of a Police Operation to Fight the Drug Plague: Distribution Unit Weight as an Objective Index
Authors: Levy Rina , Zelkowicz Avraham
Published: June 2007

Abstract:  Lod, a city near Tel‐Aviv, is considered the main drug distribution center in Israel. A major police undercover operation in Lod, lasting close to a year, was terminated in May 2003. The success or failure of such an operation is frequently measured by the number of arrests made, the hierarchical level of the dealers arrested, the number of drug stations closed down, and the decrease in heroin seizures following the operation. In this work we suggest using an additional parameter, which has a scientific, objective basis, namely, comparing the changes in the average user weight unit (“dose”) before and after the operation. We found that prior to the operation the average weight per unit was 1.1 g. Three months after the operation terminated the average weight per unit had decreased to 0.8 g and remained there for at least 4 months before rising again.
Astra Tech single‐tooth implants: an audit of patient satisfaction and soft tissue form
Authors: Palmer R. M. , Farkondeh N. , Palmer P. J. , Wilson R. F.
Published: June 2007

Aim: To investigate patient centred outcomes, soft tissue morphology, and bone levels.

Material and Methods: Sixty‐six subjects, who had completed treatment for a single implant restoration at least l year previously. Appearance was recorded photographically and bone levels and interdental contact points measured from intra‐oral radiographs using a × 7 scale loupe. Subjects completed a satisfaction questionnaire.

Results: Subjects were highly satisfied with all aspects of the restoration including the appearance of the soft tissue (median shape/colour score 6 on scale 1–6). Twenty‐eight sites in 20 subjects had no contact point between implant crown and adjacent tooth. A normal height papilla was judged to be present in 19 of these sites. These were excluded from the subsequent analysis. In the remaining 46 subjects with contact points the presence (JEMT score 3) or deficiency (score 1/2) of the papilla was significantly related to the distance to the bone level on the adjacent tooth and implant head. Differences were observed between the mesial and distal aspects of the implant restoration.

Conclusions: Examining clinicians were more critical of the restorations than the patients. The presence of a complete papilla was associated with a slightly greater distance from contact point to bone level than previously reported.
Specificity, Promiscuity and Localization of ARF Protein Interactions with NCS‐1 and Phosphatidylinositol‐4 Kinase‐IIIβ
Authors: Haynes Lee P. , Sherwood Mark W. , Dolman Nick J. , Burgoyne Robert D.
Published: June 2007

ADP‐ribosylation factor (ARF) proteins are involved in multiple intracellular vesicular transport pathways. Most studies have focused on the functions of ARF1 or ARF6 and little is known about the remaining ARF isoforms. Although the mammalian ARF proteins share a high degree of sequence identity, recent evidence has indicated that they may control distinct trafficking steps within cells. A unanswered issue is the degree of specificity of ARF family members for different interacting proteins. To investigate potential functional differences between the human ARF proteins, we have examined the localization of all human ARF isoforms and their interactions with two ARF1 binding proteins, neuronal calcium sensor‐1 (NCS‐1) and phosphatidylinositol‐4 kinase‐IIIβ (PI4Kβ). Use of a fluorescent protein fragment complementation method showed direct interactions between ARFs 1, 3, 5 and 6 with NCS‐1 but at different intracellular locations in live HeLa cells. Photobleaching experiments indicated that complementation did not detect dynamic changes in protein interactions over short‐time scales. A more specific interaction between ARFs 1/3 and PI4Kβ was observed. Consistent with these latter findings ARF1 but not ARF5 or 6 enhanced the stimulatory effect of PI4Kβ on regulated exocytosis, suggesting a specific role for class‐I ARFs in the regulation of PI4Kβ.
Light Chain C‐Terminal Region Reinforces the Stability of Clathrin Heavy Chain Trimers
Authors: Ybe Joel A. , Perez‐Miller Samantha , Niu Qian , Coates David A. , Drazer Michael W. , Clegg Mary E.
Published: June 2007

The self‐assembly of clathrin into lattices relies on the ability of heavy chain legs to form a three‐legged pinwheel structure. We investigated the role of light chains in clathrin trimerization by challenging recombinant hub (plus and minus light chain) with an anionic detergent. The binding of light chain increases the amount of detergent needed to induce detrimerization, suggesting light chains reinforced hub trimers. We also show that light chain C‐terminal residues are important for enhancing the in vitro assembly of hub at low pH. We assessed how much the C‐terminus of light chain contributed to the stability of the trimerization domain by adding full‐length and truncated light chains to trimer‐defective hub mutants, C1573S and C1573A. Adding full‐length LCb to C1573S caused some retrimerization, but little activity was restored, suggesting the majority of oligomeric C1573S was nonnative. A larger percentage of monomeric C1573A could be retrimerized into an assembly‐competent form by adding intact LCb. We also discovered that C‐terminally deleted light chains produced a heterogeneous population of hubs that were smaller than native hubs, but were assembly active. We propose a model showing how light chains reinforce the puckered clathrin triskelion. Finally, the ability of light chains to retrimerize C1573A hub suggests that the structural role of light chain may be conserved in yeast and mammals.
Stigma experiences in youth with facial differences: a multi‐site study of adolescents and their mothers*
Authors: Strauss RP , Ramsey BL , Edwards TC , Topolski TD , Kapp‐Simon KA , Thomas CR , Fenson C , Patrick DL
Published: June 2007

Structured Abstract

Authors –  Strauss RP, Ramsey BL, Edwards TC, Topolski TD, Kapp‐Simon KA, Thomas CR, Fenson C, Patrick DL

Objectives –  To describe stigma experiences of adolescents with congenital and acquired facial differences.

Design –  Used baseline cross‐sectional stigma‐related responses from a four site (Seattle WA, Galveston TX, Chicago IL and Chapel Hill NC) US study enrolling 185 English speaking, US participants ages 11–18 years old with facial differences (60% male; 80% congenital conditions). Closed‐ended, self‐administered questions drawn from the Youth Quality of Life Instrument – Facial Differences Module (YQOL‐FD) determined perceptions of stigmatization. Mothers (n = 153) were independently asked seven matching questions.

Results –  Frequencies report combined responses of ‘sometimes,’‘fairly often,’ and ‘very often.’ Mother's responses are in parentheses.

35% (47%) noticed people staring at their face in the past week.

28% (43%) talked with others about how their face looks in the past month.

29% (31%) heard others say something about their face in the past month.

32% (32%) told peers about their facial difference in the past month.

12% (12%) felt left out of doing things with peers because of how their face looks in the past month.

11% (8%) got into a fight because of how their face looks in the past month.

20% (18%) were teased about how their face looks in the past month.

Conclusions –  Stigma experiences were frequently reported by youth with facial differences and were correlated with independent parental report. This level of stigma suggests that media and public health interventions may be warranted to reduce discrimination, prejudice and negative adolescent social experiences related to facial difference.
Syndromic craniosynostosis: from history to hydrogen bonds
Authors: Cunningham ML , Seto ML , Ratisoontorn C , Heike CL , Hing AV
Published: June 2007

Structured Abstract

Authors –  Cunningham ML, Seto ML, Ratisoontorn C, Heike CL, Hing AV

The syndromic craniosynostoses, usually involving multiple sutures, are hereditary forms of craniosynostosis associated with extracranial phenotypes such as limb, cardiac, CNS and tracheal malformations. The genetic etiology of syndromic craniosynostosis in humans is only partially understood. Syndromic synostosis has been found to be associated with mutations of the fibroblast growth factor receptor family (FGFR1, ‐R2, ‐R3), TWIST1, MSX2, and EFNB1. Apert, Pfeiffer, Crouzon, and Jackson‐Weiss syndromes are due to gain‐of‐function mutations of FGFR2 in either the Ig II–III linker region (Apert) or Ig III domain. Loss of function mutations of TWIST1 and gain‐of‐function mutations of MSX2 lead to Saethre–Chotzen and Boston‐type syndromes, respectively. The mutations in Pfeiffer (FGFR1), Muenke (FGFR3), and Apert syndrome (FGFR2) are caused by the same amino acid substitution in a highly conserved region of the Ig II–III linker region of these proteins, which suggests that these receptor tyrosine kinases have an overlapping function in suture biology. In this review we will discuss the historical descriptions, current phenotypes and molecular causes of the more common forms of syndromic craniosynostosis.
Effect of Bleaching Agents on the Hardness and Morphology of Enamel
Authors: LOPES GUILHERME CARPENA , BONISSONI LEANDRO , BARATIERI LUIZ NARCISO , VIEIRA LUIZ CLÓVIS C. , MONTEIRO SYLVIO
Published: June 2007

Purpose: The goal of the present laboratory study was to analyze the effect of two home bleaching agents (Opalescence 10%, Ultradent, and Hi‐Lite II, Shofu) as well as the separate solutions of 10% carbamide peroxide primary components (3% hydrogen peroxide and 7% urea) on enamel microhardness and surface morphology.

Materials and Methods: Thirty human molars stored in water for no longer than 3 months were selected. Their facial and lingual surfaces were embedded in acrylic resin, and the specimens were polished with up to 600‐grit sandpaper. The 30 molar sections were divided into five groups as per treatment modality (n = 6); group 1, 10% carbamide peroxide bleach with carbopol (Opalescence, Ultradent); group 2, oxygen‐free gel bleach (Hydroxylite, Hi‐Lite II, Shofu); group 3, 3% hydrogen peroxide with carbopol (Dermus Pharmacy, Florianopolis, SC, Brazil); group 4, 7% urea treatment (Dermus Pharmacy); and control, group 5, artificial saliva (Dermus Pharmacy). Prior to treatment, six indentations (Vickers) were made on each of the six surfaces in each group under a load of 100 g for 30 seconds. Bleaching procedure was conducted for 3 hours per day for 2 weeks, the control group excepted. Following each bleaching session, the specimens were washed with deionized water and kept in artificial saliva at 37°C, this solution being changed daily. Pre‐ and post‐treatment microhardness data were analyzed using a two‐way analysis of variance. In a similar way, 30 other specimens underwent the same procedures. After the bleaching period, the samples were observed under the scanning electron microscope.

Results: Specimens submitted to bleaching treatment with 3% hydrogen peroxide gel as described in this study showed a significant reduction of surface microhardness (p < .0001). The other treatment modalities had no effect on surface microhardness. No morphologic alterations were observed on enamel submitted to bleaching gel of 10% carbamide peroxide (Opalescence), oxygen‐free gel (Hi‐Lite II, Shofu), or 7% urea solution compared with the control (artificial saliva). However, the specimens bleached for 3 hours per day for 2 weeks with 3% hydrogen peroxide gel presented areas of mild erosion. The effect, nevertheless, was not uniform, occurring with varying intensity on all samples of enamel bleached with 3% hydrogen peroxide.

CLINICAL SIGNIFICANCE

Bleaching treatment conducted with two home bleaching agents (Opalescence 10%, Ultradent, and Hi‐Lite 11, Shofu) had no adverse effects on enamel microhardness or on surface morphology. Bleaching with 3% hydrogen peroxide can have a negative effect on enamel hardness and surface morphology when performed as described in this study