bluuebunny/crossref_metadata_2025 huggingface dataset:
The Synoptic Regulation of Dryline Intensity
Authors: Schultz David M. , Weiss Christopher C. , Hoffman Paul M.
Published: May 2007

To investigate the role of synoptic-scale processes in regulating the strength of the dryline, a dataset is constructed of all drylines occurring within the West Texas Mesonet (WTM) during April, May, and June of 2004 and 2005. In addition, dewpoint and wind data were collected from stations on the western (Morton; MORT) and eastern (Paducah; PADU) periphery of the WTM domain (230 km across), generally oriented east–west across the typical location of the dryline in west Texas. Drylines were characterized by two variables: the difference in dewpoint between MORT and PADU (hereafter, dryline intensity) and the difference in the eastward component of the wind between MORT and PADU (hereafter, dryline confluence). A high degree of correlation existed between the two variables, consistent with a strong role for dryline confluence in determining dryline intensity. Some cases departing from the strong correlation between these variables represent synoptically quiescent drylines whose strength is likely dominated by boundary layer mixing processes.

Composite synoptic analyses were constructed of the upper and lower quartiles of dryline intensity, termed STRONG and WEAK, respectively. STRONG drylines were associated with a short-wave trough in the upper-level westerlies approaching west Texas, an accompanying surface cyclone over eastern New Mexico, and southerly flow over the south-central United States. This synoptic environment was favorable for enhancing the dryline confluence responsible for strengthening the dryline. In contrast, WEAK drylines were associated with an upper-level long-wave ridge over Texas and New Mexico, broad surface cyclogenesis over the southwestern United States, and a weak lee trough—the dryline confluence favorable for dryline intensification was much weaker. A third composite termed NO BOUNDARY was composed of dates with no surface airstream boundary (e.g., front, dryline) in the WTM domain. The NO BOUNDARY composite featured an upper-level long-wave ridge west of Texas and no surface cyclone or lee trough. The results of this study demonstrate the important role that synoptic-scale processes (e.g., surface lee troughs, upper-level short-wave troughs) play in regulating the strength of the dryline. Once such a favorable synoptic pattern occurs, mesoscale and boundary layer processes can lead to further intensification of the dryline.
Mesoscale Dynamics of the Trowal and Warm-Frontal Regions of Two Continental Winter Cyclones
Authors: Han Mei , Rauber Robert M. , Ramamurthy Mohan K. , Jewett Brian F. , Grim Joseph A.
Published: May 2007

The dynamic and thermodynamic structure and associated frontal circulations within the trowal and warm-frontal regions of two extratropical winter cyclones are examined using numerical simulations. In each cyclone, the warm, moist airstream originating in the warm sector was found to bifurcate upon reaching the warm front. One branch of the flow turned anticyclonically eastward, corresponding to the warm conveyor belt, while the second branch turned cyclonically westward becoming the trowal airstream. The dynamic forcing of vertical motion within the two airstreams was investigated using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5), both from an analysis of the Sawyer–Eliassen (SE) equation in two dimensions and from complete model solutions.

Shearing deformation, associated with the jet stream and the low-level cyclonic flow, dominated confluent deformation near the trowal in both cases. The shearing deformation was accompanied by cold advection associated with an intrusion of cold, dry air aloft. The configuration of isentropes and the wind field led to frontogenesis on the equatorward side of the trowal and frontolysis farther south on the poleward side of the jet stream. The SE solution showed a circulation centered on the frontogenesis–frontolysis couplet, with air rising in the trowal and sinking within the dry air mass on the trowal’s equatorward side. The rising branch of the circulation was responsible for the wide swath of snowfall coincident with the trowal. From the vicinity of the bifurcation axis eastward along the warm-frontal zone, confluent deformation dominated within the troposphere. Frontogenesis in this region produced a direct circulation whose rising branch accounted for the production of precipitation over the warm-frontal zone. Diabatic processes associated with latent heating and cooling produced frontogenesis–frontolysis couplets and significantly modified the transverse frontal circulations. The ascending motion was amplified by a factor of 2 or greater compared with the ascending motion solely due to horizontal deformation. The width of the ascending branch was also narrowed compared with that solely from deformation. Vertical tilting, a result of the secondary circulation generated by horizontal deformation, produced frontogenesis–frontolysis couplets that acted to oppose and reduce the magnitude of the secondary circulation. A conceptual model of the effect of these processes on the production and organization of snowfall in the two cyclones is presented.
Dendritic Patterns in Tropical Cumulus: An Observational Analysis
Authors: Nicholls Stephen D. , Young George S.
Published: May 2007

An observational analysis of the structure and synoptic setting of tropical dendritic cumulus formations was undertaken using 30 months of global data from the Moderate Resolution Imaging Spectroradiometer aboard the National Aeronautics and Space Administration Terra satellite, the Quick Scatterometer aboard the SeaWinds satellite, and the National Centers for Environmental Prediction global reanalysis. This analysis yielded 1216 cases of tropical dendritic cumulus formations of which 61 were randomly selected for quantitative study. From these sample cases, it was found that dendritic patterns in shallow cumulus occurred over warm tropical oceans in response to cold air advection. They typically dissipate downstream in regions of cooler water, neutral to warm advection, or deep convection. Moreover, shallow cumulus formations take on a dendritic pattern only in areas where the background wind velocity is between 1.5 and 13 m s−1 in the surface to the 850-mb layer and a shallow layer of conditional instability is present. Individual cumulus clouds in these dendritic formations are arranged in a compound, hierarchical branching pattern in which each element of the pattern takes the form of a Y-shaped cloud line. Analysis of the cloud pattern observations in conjunction with the scatterometer-derived surface winds and the lower-tropospheric wind profiles from reanalysis data reveals that the individual Y elements are aligned closely with the surface wind direction, as linear cloud streets would be. These Y elements are oriented so that their forked end aligns as closely as possible with the surface-to-850-mb shear vector, even when this conflicts with the surface wind direction. A formation mechanism is hypothesized by which the secondary circulation of a towering cumulus line modifies the shear and stability profiles in the adjacent areas to favor shallower cumulus lines oriented at an angle to itself, thus forming a hierarchical branching structure. This hypothesis is supported by stability profiles from the reanalysis data.
Collocated Radar and Radiosonde Observations of a Double-Brightband Melting Layer in Northern California
Authors: Martner Brooks E. , Neiman Paul J. , White Allen B.
Published: May 2007

A strong elevated temperature inversion in a landfalling winter storm in northern California produced two simultaneous melting layers with associated radar bright bands. The storm was observed with scanning and profiling radars. Serial radiosonde launches from the scanning radar site precisely documented the evolving temperature structure of the air mass that produced the double bright band. The radiosonde and radar observations, which were coincident in location and time, clearly illustrate the cause (two melting layers) and effect (two bright bands) of this unusual phenomenon. An automated algorithm for determining the melting-layer height from profiling radar data was tested on this situation. In its operational form, the algorithm detects only the lower melting layer, but in modified form it is capable of detecting both melting layers simultaneously.
How Does the Tibetan Plateau Affect the Transition of Indian Monsoon Rainfall?
Authors: Sato Tomonori , Kimura Fujio
Published: May 2007

The roles of the Tibetan Plateau (TP) upon the transition of precipitation in the south Asian summer monsoon are investigated using a simplified regional climate model. Before the onset of the south Asian monsoon, descending flow in the midtroposphere, which can be considered as a suppressor against precipitation, prevails over northern India as revealed by the NCEP–NCAR reanalysis data. The descending motion gradually weakens and retreats from this region before July, consistent with the northwestward migration of the monsoon rainfall. To examine a hypothesis that the dynamical and thermal effects of TP cause the midtropospheric subsidence and its seasonal variation, a series of numerical experiments are conducted using a simplified regional climate model. The mechanical effect of the TP generates robust descending flow over northern India during winter and spring when the zonal westerly flow is relatively strong, but the effect becomes weaker after April as the westerly flow tends to be weaker. The thermal effect of the TP, contrastingly, enhances the descending flow over north India in the premonsoonal season. The descending flow enhanced by the thermal effect of the TP has a seasonal cycle because the global-scale upper-level westerly changes the energy propagation of the thermal forcing response. The subsidence formed by the mechanical and thermal effects of the TP disappears over northern India after the subtropical westerly shifts north of the plateau, the seasonal change of which is in good agreement with that in the reanalysis data. The retreat of the descending flow can be regarded as the withdrawal of the premonsoon season and the commencement of the south Asian monsoon. After that, the deep convection, indicating the onset of the Indian summer monsoon, is able to develop over north India in relation to the ocean–atmosphere and land–atmosphere interaction processes. Northwest India is known to be the latest region of summer monsoon onset in south Asia. Thus, the thermal and mechanical forcing of the TP has great impact on the transition of the Indian monsoon rainfall by changing the midtropospheric circulation.
A Lightning Data Assimilation Technique for Mesoscale Forecast Models
Authors: Mansell Edward R. , Ziegler Conrad L. , MacGorman Donald R.
Published: May 2007

Lightning observations have been assimilated into a mesoscale model for improvement of forecast initial conditions. Data are used from the National Lightning Detection Network (cloud-to-ground lightning detection) and a Lightning Mapping Array (total lightning detection) that was installed in western Kansas–eastern Colorado. The assimilation method uses lightning as a proxy for the presence or absence of deep convection. During assimilation, lightning data are used to control the Kain–Fritsch (KF) convection parameterization scheme. The KF scheme can be forced to try to produce convection where lightning indicated storms, and, conversely, can optionally be prevented from producing spurious convection where no lightning was observed. Up to 1 g kg−1 of water vapor may be added to the boundary layer when the KF convection is too weak. The method does not employ any lightning–rainfall relationships, but rather allows the KF scheme to generate heating and cooling rates from its modeled convection. The method could therefore easily be used for real-time assimilation of any source of lightning observations. For the case study, the lightning assimilation was successful in generating cold pools that were present in the surface observations at initialization of the forecast. The resulting forecast showed considerably more skill than the control forecast, especially in the first few hours as convection was triggered by the propagation of the cold pool boundary.
Prediction of Consensus Tropical Cyclone Track Forecast Error
Authors: Goerss James S.
Published: May 2007

The extent to which the tropical cyclone (TC) track forecast error of a consensus model (CONU) routinely used by the forecasters at the National Hurricane Center can be predicted is determined. A number of predictors of consensus forecast error, which must be quantities that are available prior to the official forecast deadline, were examined for the Atlantic basin in 2001–03. Leading predictors were found to be consensus model spread, defined to be the average distance of the member forecasts from the consensus forecast, and initial and forecast TC intensity. Using stepwise linear regression and the full pool of predictors, regression models were found for each forecast length to predict the CONU TC track forecast error. The percent variance of CONU TC track forecast error that could be explained by these regression models ranged from just over 15% at 48 h to nearly 50% at 120 h. Using the regression models, predicted radii were determined and were used to draw circular areas around the CONU forecasts that contained the verifying TC position 73%–76% of the time. Based on the size of these circular areas, a forecaster can determine the confidence that can be placed upon the CONU forecasts. Independent data testing yielded results only slightly degraded from those of dependent data testing, highlighting the capability of these methods in practical forecasting applications.
Surface Data Assimilation Using an Ensemble Kalman Filter Approach with Initial Condition and Model Physics Uncertainties
Authors: Fujita Tadashi , Stensrud David J. , Dowell David C.
Published: May 2007

The assimilation of surface observations using an ensemble Kalman filter (EnKF) approach is evaluated for the potential to improve short-range forecasting. Two severe weather cases are examined, in which the assimilation is performed over a 6-h period using hourly surface observations followed by an 18-h simulation period. Ensembles are created in three different ways—by using different initial and boundary conditions, by using different model physical process schemes, and by using both different initial and boundary conditions and different model physical process schemes. The ensembles are compared in order to investigate the role of uncertainties in the initial and boundary conditions and physical process schemes in EnKF data assimilation. In the initial condition ensemble, spread is associated largely with the displacement of atmospheric baroclinic systems. In the physics ensemble, spread comes from the differences in model physics, which results in larger spread in temperature and dewpoint temperature than the initial condition ensemble, and smaller spread in the wind fields. The combined initial condition and physics ensemble has properties from both of the previous two ensembles. It provides the largest spread and produces the best simulation for most of the variables, in terms of the rms difference between the ensemble mean and observations. Perhaps most importantly, this combined ensemble provides very good guidance on the mesoscale features important to the severe weather events of the day.
Processual Learning, Environmental Pluralism, and Inherent Challenges of Managing a Socioeconomic Crisis: The Case of the Canadian Mad Cow Crisis
Authors: Charlebois Sylvain , Labrecque JoAnne
Published: May 2007

On May 20, 2003, the report of a single infected cow caused Canada to join the list of countries infected with Bovine Spongiform Encephalopathy (BSE), more commonly known as “mad cow” disease. In this article, by considering the Canadian cattle industry as a political economy, the authors assess factual aspects of the first year of the Canadian BSE crisis from a crisis management perspective. Literature suggests that the processual approach of crisis management can assist marketers in improving their responsiveness to socioeconomic disasters, thereby extending the significance of crisis management theory in marketing. Building a responsive, learning-based approach to crisis management should lead marketers to appreciate the plurality of their environment, the primary source of uncertainty. Building a responsive, learning-based approach to crisis management into the industry will safeguard both the industry and the public against both further socioeconomic crises and further food safety concerns.
Export Processing Zones in Development and International Marketing: An Integrative Review and Research Agenda
Authors: Papadopoulos Nicolas , Malhotra Shavin
Published: May 2007

Export processing zones (EPZs) are areas within developing countries that offer incentives and a barrier-free environment to promote economic growth by attracting foreign investment for export-oriented production. The number of zones internationally, countries hosting EPZs, and firms operating in them, and the business volume they handle, are all growing rapidly, suggesting their importance. Yet, business research on EPZs is virtually nonexistent, leading to poor understanding of their role in international marketing. This article draws from the literature in economics, macromarketing, and other disciplines to provide an integrative review of the concept. The authors then adopt a macromarketing perspective to develop a new definition of EPZs, typologies of free export zones and of their benefits for host nations and investors, and the notion of a “virtual network” of free zones as part of the international market system. The authors conclude by highlighting the need and potential directions for new research in this field.
Bilateral Basal Ganglia Lesions After Hypoglycemic Coma in a 6-Year-Old Child
Authors: Kara Cengiz , Aydin Ömer Faruk , Aslan Belma , Yavuz Gürer Y.K.
Published: May 2007

Imaging findings of brain damage due to neonatal hypoglycemia are known; however, the effect of childhood hypoglycemia on the brain has not been described well. The authors present the case of a 6-year-old girl who had seizures secondary to hypoglycemia followed up for 1 year as epilepsy. The patient had experienced a hypoglycemic coma attack about 1 year before. Brain magnetic resonance imaging showed atrophy of the cerebrum and cerebellum and bilateral symmetrically hyperintense lesions in the putamina. The patient was diagnosed with hypoglycemia due to hyperinsulinism.
3-Methylglutaconic Aciduria Type 4 Manifesting as Leigh Syndrome in 2 Siblings
Authors: Muñoz Jareño Nuria , Fernández-Mayoralas Daniel Martín , Pérez-Cerdá Silvestre Celia , Merinero Cortés Begoña , Ugarte Pérez Magdalena , Campos-Castelló Jaime
Published: May 2007

The authors report the case of a pair of siblings with 3-methylglutaconic aciduria type 4 manifesting as Leigh syndrome. Disease progression was monitored from birth until the present. Both patients fulfilled the diagnostic criteria for Leigh syndrome along with increased urinary excretion of 3-methylglutaconic acid and 3-methylglutaric acid (biochemical markers of methylglutaric acid) in several determinations. No mitochondrial respiratory chain defects in muscle biopsy were detected. Although mitochondrial abnormalities are the most common known cause of Leigh syndrome, there have been several reports of links with nonmitochondrial metabolic disorders. Descriptions of 3-methylglutaric acid type 4 associated with Leigh syndrome are rare.
A Case of Cerebello-oculo-renal Syndrome with Situs Inversus Totalis: A New Phenotype
Authors: Aydinoz Secil , Ersen Atilla , Karademir Ferhan , Suleymanoglu Selami , Ozkaya Halit , Gocmen Ismail
Published: May 2007

Cerebello-oculo-renal syndromes are rare, autosomal recessive syndromes with uncertain nosology. Cerebello-oculo-renal syndromes involve many congenital malformations and may be associated with other disorders. The authors present a case of cerebello-oculo-renal syndrome with situs inversus totalis from a consanguineous family. The patient had cerebellar vermis hypoplasia, ocular abnormalities (Leber congenital amaurosis with retinal dystrophy, abnormal eye movements), developmental delay, growth deficiency, severe renal failure, and severe anemia. Imaging studies showed molar tooth sign, which was compatible with cerebello-oculo-renal syndromes and situs inversus totalis.
Focal Cortical Malformations Can Show Asymmetrically Higher Uptake on Interictal Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography (PET)
Authors: Poduri Annapurna , Golja Anna , Takeoka Masanori , Bourgeois Blaise F. D. , Connolly Leonard , Riviello James J.
Published: May 2007

Interictal fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) is a component of the presurgical evaluation of patients with medically intractable epilepsy, including patients with malformations of cortical development. The authors describe 3 cases of focal cortical malformations that displayed asymmetrically higher uptake on FDG-PET performed in the interictal state in patients undergoing evaluation for possible focal resection for refractory localization-related epilepsy. The evaluation included routine and prolonged video electroencephalography (EEG), magnetic resonance imaging (MRI), interictal FDG-PET with concurrent EEG, and single-photon emission computed tomography (SPECT). All 3 patients had focal cortical malformations on MRI corresponding to regions of asymmetrically higher uptake on FDG-PET. EEG confirmed that the FDG-PET studies were performed in the interictal state. The lesions included a large region of subcortical heterotopia in the right frontal lobe, a left temporal lobe dysplasia, and a region of subcortical heterotopia in the right occipital lobe. In both patients with subcortical heterotopia, there were other focal regions of cortical malformation that were not associated with abnormal or asymmetric uptake on FDG-PET. Previous reports describe decreased uptake on interictal PET in most cases of focal cortical malformations. Normal to increased uptake has been reported with band heterotopia. The authors demonstrate that other types of focal malformations of cortical development, including focal subcortical heterotopia and lobar dysplasia, can be associated with asymmetrically higher uptake on interictal FDG-PET.
Extensive Cortical Magnetic Resonance Signal Change in Proximal Urea Cycle Disorder
Authors: Bindu P.S. , Sinha S. , Taly A.B. , Chandrasekhar H.S. , Christopher R. , Arunodaya G.R. , Shetty T.
Published: May 2007

The authors report a 3-year 8-month-old girl presenting with episodic hyperammonemic encephalopathy probably due to a proximal urea cycle disorder. The magnetic resonance imaging (MRI) of the brain performed during the third episode revealed extensive and diffuse cerebral cortical signal changes with sparing of occipital cortex. It is believed that intracerebral accumulation of glutamine mainly in astrocytes is the major cause of the encephalopathy. This results in astrocyte swelling, brain edema, intracranial hypertension, and cerebral hypoperfusion.
FXIII Gene Val34Leu Polymorphism in Turkish Children with Cerebral Infarct
Authors: Akar Nejat , Dönmez Buket , Deda Gülhis
Published: May 2007

A common polymorphism of the FXIIIA gene, which is characterized by a Val → Leu exchange at amino acid position 34 (FXIII Val34Leu), was studied in this case-control study. The authors sought to determine whether there was an association between this polymorphism and pediatric stroke. The case-control study included 116 patients with cerebral infarct who were younger than 18 years. All were clinically diagnosed, and the infarction was verified with cranial imaging of the brain. The data revealed that the FXIII gene Val34Leu polymorphism was not associated independently with pediatric stroke in the population and that it does not have any effect in PT 20210A carriers. However, although the difference was not significant, the risk of thrombosis decreased 2-fold to the protective side in patients carrying FV1691A. This may be an important clue and needs further study in FV1691A carriers with and without thrombosis.
Magnetic Resonance Imaging in Child Abuse
Authors: Eltermann Thomas , Beer Meinrad , Girschick Hermann J.
Published: May 2007

Magnetic resonance imaging is a particularly important diagnostic method when bone and soft tissue lesions of inflammatory or malignant origin need to be analyzed. Traumatic lesions often are evaluated using standard radiographs or computed tomography. Both of these methods evaluate fractures appropriately; however, bone bruise, bone bending, and soft tissue lesions might be underestimated. Especially in the evaluation of suspected child abuse, magnetic resonance imaging can contribute significantly to making the diagnosis, especially when the reported history is not conclusive.
Combination Therapy of Interferon and Ribavirin Versus Interferon Monotherapy in Treatment of Chronic Hepatitis C: A Meta-analysis of Clinical Trials
Authors: Khader Yousef S. , Dweek Anmar , Alkafajei Ahmad , Rabi' Atallah Z.
Published: May 2007

This meta-analysis was conducted to assess the efficacy and safety of interferon and ribavirin combination therapy (CT) versus interferon monotherapy (IMT) in inducing sustained response in interferon-naïve, relapser, and nonresponder chronic hepatitis C patients. A literature search was performed using the MEDLINE database for clinical trials published in the period between 1995 and 2003. A total of 31 randomized trials and 7 nonrandomized trials comparing CT with interferon alone or comparing different dose regimens of CT were included in this meta-analysis. The primary outcome measure was sustained virological response. The summary estimate of the odds ratio was obtained using the random effect model. The study showed that sustained virological response rate was significantly higher in interferon-naïve, relapser, and nonrespondent chronic hepatitis C patients who were on CT compared to IMT (odds ratio = 3.23, 17.65, and 4.71, respectively). There was no statistically significant difference in virological and biochemical responses between different dose regimens of CT. Side effects, dose reduction, and treatment discontinuation rates were significantly higher in patients receiving CT compared with IMT. Treatment with interferon plus ribavirin has a significant benefit on the virological and biochemical response in patients with chronic hepatitis C irrespective to the previous treatment, and it should be considered the treatment of choice in naïve, relapser, and nonrespondent chronic hepatitis C patients.
Stability of Donepezil in an Extemporaneously Prepared Oral Liquid
Authors: Yamreudeewong Weeranuj , Dolence Eric Kurt , Pahl Deborah
Published: May 2007

The stability of donepezil in an extemporaneously prepared oral liquid was studied. An aqueous liquid formulation of donepezil was prepared by reconstituting the powder from triturated 5-mg tablets with equal amounts of deionized water and 70% sorbitol solution with an expected donepezil concentration of 1 mg/mL. Polyethylene terephthalate plastic bottles containing donepezil liquid preparation were stored at ambient room temperature (22° C-26° C) and in the refrigerator (4° C-8° C). After a storage time of 1, 2, 3, and 4 weeks, donepezil liquid samples were analyzed in triplicate for donepezil concentrations by high-performance liquid chromatography. The concentrations of donepezil were found to be within the acceptable limit (± 10% of the initial concentration) in all test samples, which indicated that donepezil liquid preparation was stable at room temperature and in the refrigerator for up to 4 weeks. In addition, our study findings indicated that there was no microbial growth in the extemporaneously prepared donepezil liquid preparation after a storage period of 4 weeks in the refrigerator. In summary, the results of our study revealed that donepezil is stable (no significant loss of donepezil concentration and no microbial growth) in an extemporaneously prepared oral liquid when stored in the refrigerator for up to 4 weeks.
Nonprescription Medication Use by Infants and Children: Product Labeling Versus Evidence-Based Medicine
Authors: Orr Katherine Kelly , Matson Kelly L. , Cowles Brian J.
Published: May 2007

Nonprescription or over-the-counter (OTC) medication use has been an increasing market over the past years. In addition to adult use of these medications, children also account for this trend. Although relatively safe when used according to package labeling and professional direction, serious adverse drug events and toxicity associated withOTC use among infants and children are becoming more common. The purpose of this review is to help the health care practitioner select and counsel on pediatric OTC products based on labeling and efficacy data in 3 main areas: cough and cold, analgesics, and treatment of gastroenteritis.
Prophylactic Antibiotic Compliance with Published Guidelines
Authors: Erstad Brian L. , Schultz Jill M.
Published: May 2007

Purpose: To examine the rate of compliance with National Surgical Infection Prevention Project performance measures and compliance with American Society of Health-System Pharmacists guidelines for procedures not covered by these measures and to evaluate noncompliance for explanatory factors. Methods: A retrospective review of all patients receiving prophylactic antibiotics for Class I (clean) or Class II (clean-contaminated) surgical procedures. Information collected included antibiotic ordered, antibiotic given, dose of antibiotic, time of administration, time of incision, time of closure, duration of procedure, need for re-dosing during the procedure, documentation of re-dosing administered, and antibiotic discontinuation. Results: Choice of antibiotic for prophylaxis was appropriate in 99% of the 568 procedures. Antibiotic was administered too early in 94 of 527 (17.8%) patients. Prophylactic antibiotics were inappropriately continued for more than 24 hours in 43 of 216 (20%) patients undergoing noncardiothoracic procedures and for more than 48 hours in 4 of 10 (40%) in patients undergoing cardiothoracic surgery. Conclusion: Although improvements in key performance measures related to prophylactic antibiotic agent selection, timing of administration, and discontinuation have been made compared to data collected in a larger multicenter study conducted at the beginning of this century, there remains considerable room for improvement.
Job Satisfaction Among Staff, Clinical, and Integrated Hospital Pharmacists
Authors: Kerschen Ann M. , Armstrong Edward P. , Hillman Tara N.
Published: May 2007

Purpose: To determine whether staff, clinical, or integrated hospital pharmacists have greater job satisfaction and if sex, years worked as a pharmacist, or having children changes job satisfaction. Methods: A prospective study was performed by distributing a 63-item questionnaire to inpatient pharmacists working at 2 hospitals. Respondents mailed the completed questionnaires to the investigators. Results: Questionnaires were completed by 38 participants (mean age [SD]= 38.36 [10.97]). Fourteen (36.85%) participants who spent 0% to 40% of their time in clinical activities were categorized as staff, 10 (26.30%) who spent 41% to 60% of their time in clinical activities were integrated, and 14 (36.85%) who spent greater than 61% of their time in clinical activities were clinical pharmacists. All pharmacists reported mean satisfaction scores above 2.5, indicating that all were satisfied in their jobs. Differences were noted in the amount of satisfaction. For work environment and professional interaction, integrated pharmacists were more satisfied than staff (P < .05). For professional interaction and personal outlook, clinical pharmacists were more satisfied than staff (P < .05). Conclusion: Job satisfaction was directly related to the number of clinical activities performed. Integrated and clinical pharmacists were both more satisfied than staff pharmacists.
Ring-closing Metathesis Approach to a 16-Membered Macrocycle of Kendomycin
Authors: Sengoku Tetsuya , Uemura Daisuke , Arimoto Hirokazu
Published: May 2007

An approach to the macrocyclic core of kendomycin is described in which the Nozaki–Hiyama–Kishi coupling and a ring-closing olefin metathesis are the key reactions.
Novel Mesoporous CaO–B2O3–SiO2 Glasses with In Vitro Bioactivity
Authors: Xiu Tongping , Liu Qian , Wang Jacheng
Published: May 2007

Wormhole-like-ordered mesoporous CaO–B2O3–SiO2 (MCBS) glasses, prepared by a combination of surfactant-templating, sol–gel method and evaporation-induced self-assembly (EISA) processes, show good in vitro bioactivity, demonstrated by final formation of plate-like-carbonated calcium-deficient hydroxyapatite (d-HAp) on the surface after soaking in simulated body fluid (SBF) for a short period of time.
Genetic and Environmental Influences on Self-Concept in Female Preadolescent Twins: Comparison of Minnesota and Seoul Data
Authors: Hur Yoon-Mi
Published: May 2007

It has been argued that culture significantly influences the developmental basis of self-concept. The goal of the present study is to compare the relative importance of genetic and environmental factors to explain individual differences in various dimensions of self-concept in female preadoles- cents of Minnesota in the United States and Seoul in South Korea. Two hundred and eighteen monozygotic (MZ) and 137 dizygotic (DZ) twin pairs from the Minnesota Twin Family Study (MTFS) and 74 MZ and 42 DZ twin pairs from the Seoul Twin Family Study (STFS) completed the 6 cluster scales of the Piers–Harris Children's Self-Concept Scale (P–H). The 6 cluster scales of the P-H include Popularity, Physical Appearance and Attributes, Behavior, Intellectual Competence and School Status, Anxiety, and Happiness and Satisfaction. Univariate model- fitting analyses were performed. In both samples, a model incorporating shared and nonshared environmental influences fitted the data best for Popularity, Anxiety, and Intellectual Competence and School Status, whereas a model including additive genetic and nonshared environmental factors provided the best fit for Physical Appearance and Attributes, and Behavior. The univariate model did not yield an adequate fit for Happiness and Satisfaction. For Physical Appearance and Attributes, and Intellectual Competence and School Status, estimates of additive genetic and environmental factors were significantly different between the MTFS and the STFS samples. For Popularity, Anxiety, and Behavior, however, the genetic and environmental estimates were comparable between the two samples.
Genetic and Environmental Etiology of Effortful Control
Authors: Yamagata Shinji , Takahashi Yusuke , Kijima Nobuhiko , Maekawa Hiroko , Ono Yutaka , Ando Juko
Published: May 2007

We examined whether effortful control (EC), a temperament proposed by Rothbart and Bates (1998), has genetically coherent structure. A self- report measure of EC was administered to 450 Japanese twins (151 males and 299 females, ages 17 to 32 years) including 152 monozygotic and 73 dizygotic pairs. Univariate genetic analysis revealed that AE model fit best for the total EC as well as its subscales. The heritability estimate for total EC was 49%, and the estimates for subscales ranged between 32% and 45%. Multivariate genetic analysis revealed that the subscales of EC were genetically correlated to a high degree and environmentally correlated to a moderate degree. These results suggest that EC has substantial genetic basis and genetically coherent structure, supporting the validity of the construct. The implications to molecular genetic study and study of psychopathology were discussed.
Genetic and Environmental Influences on Finger-Sucking and Nail-Biting in Japanese Twin Children
Authors: Ooki Syuichi
Published: May 2007

The purpose of this study was to clarify the genetic contribution to finger-sucking and nail- biting in childhood using the largest databases available on Japanese twins. The subjects were 1131 pairs of 12-year-old twin children, consisting of 1057 males and 1205 females. All data were gathered by maternal questionnaire, and responses to the questionnaire were checked in the medical interview. The prevalence of finger-sucking between 0 to 2 years was 40% in males and 43% in females (p= .0053). The prevalence of nail-biting up until the age of 12 years was 28% in males and 26% in females (nonsignificant). Concordance rates and polychoric correlations were all higher in monozygotic pairs than in dizygotic pairs, irrespective of the sex combination. Univariate and bivariate genetic analyses using structural equation modeling was performed. The results showed that the proportion of total phenotypic variance attributable to genetic influences was 66% in males and 50% in females for finger-sucking, and 50% in both males and females for nail-biting. A co-occurrence of finger-sucking and nail-biting was observed in 17.7% of males (tetrachoric correlation:r= .40) and 15.7% of females (r= .32), which was attributed partly to common genetic or environmental factors. The proportion of total shared variance explained by genetic factors was 67%.
Verification of Self-Report of Zygosity Determined via DNA Testing in a Subset of the NAS-NRC Twin Registry 40 Years Later
Authors: Reed Terry , Plassman Brenda L. , Tanner Caroline M. , Dick Danielle M. , Rinehart Shannon A. , Nichols William C.
Published: May 2007

The National Academy of Sciences — National Research Council (NAS-NRC) twin panel, created nearly 50 years ago, had twin zygosity determined primarily via a similarity questionnaire that has been estimated to correctly classify at least 95% of twins. In the course of a study on the genetics of healthy ageing in the NAS-NRC twins, DNA was collected for genome-wide scanning and zygosity confirmation was examined in 343 participating pairs. The sample was supplemented from two other studies using NAS-NRC twins where one or both co-twins were suspected to have Alzheimer disease or another dementia, or Parkinson's disease. Overall 578 twin pairs with DNA were analyzed. Zygosity assignment for 96.8% (519/536) was confirmed via questionnaire. Among 42 pairs whose questionnaire responses were inconclusive for assigning zygosity, 50% were found to be monozygous (MZ) and 50% were dizygous (DZ). There was some evidence for greater misclassification of presumed DZ pairs in the healthy ageing study where participation favored pairs who were similar in having a favorable health history and willingness to volunteer without any element of perceived risk for a specific disease influencing participation.
The Cognitive Cost of Being a Twin: Two Whole-Population Surveys
Authors: Deary Ian J. , Pattie Alison , Wilson Valerie , Whalley Lawrence J.
Published: May 2007

Do twins have a lower mean IQ score than singletons? Previous studies have not examined whole populations and are likely to be biased. Twin data from two whole-population surveys of IQ at age 11 years were examined: the Scottish Mental Surveys of 1932 and 1947. Additional variables from childhood were examined as possible mediating effects. There were 1080 twins from the 1932 survey, and 949 from the 1947 survey. In both surveys twins scored lower on the Moray House Test of verbal reasoning, equivalent to a deficit of about 5 IQ points. In the Scottish Mental Survey of 1947 the whole-population group of twins was compared in detail with a representative population sample. The same mental ability difference of about 5 IQ points was found, and was not accounted for by father's occupation, overcrowding in the childhood home, childhood height, school attendance or the number of people in the family.
Effects of Twin Separation in Primary School
Authors: van Leeuwen Marieke , van den Berg Stéphanie M. , van Beijsterveldt Toos C. E. M. , Boomsma Dorret I.
Published: May 2007

We studied the short- and long-term effects of classroom separation in twins on behavior problems and academic performance. Short-term effects were studied at age 7 in twins separated at age 5 and long-term effects at age 12 in twins who had been separated or together most of the time at school. Behavior problems were rated by mothers (Child Behavior Checklist at ages 3, 7 and 12) and teachers (Teacher Report Form at ages 7 and 12). Academic achievement was measured at age 12 using a national academic achievement test (CITO). At age 7, twins from separated pairs had more internalizing and externalizing problems than non- separated twins, as rated by both mothers and teachers. Only for the maternal ratings of internalizing problems, however, could these effects be attributed to the separation itself and not to preexisting problems (at age 3) between separated and nonseparated twins. Long-term effects of separation were significant for maternal and teacher ratings of internalizing and externalizing problems, but these effects could be explained by preexisting differences between separated and nonseparated groups. There were no differences in academic achievement between the separated and nonsepa- rated group. These results suggest that the decision to separate twins when they go to school is based in part on the existing behavioral problems of the twins and that, in the long run, separation does not affect problem behavior or academic achievement. The findings were the same for monozygotic and dizygotic twins.
Fetal Growth Restriction and Schizophrenia: A Swedish Twin Study
Authors: Nilsson Emma , Stålberg Gabriella , Lichtenstein Paul , Cnattingius Sven , Olausson Petra Otterblad , Hultman Christina M.
Published: May 2007

Obstetric complications increase the risk of schizophrenia. However, it is not known whether there is a causal relation or whether the association is mediated by genetic and/or shared environmental effects. The aim of this study was to investigate the associations between birthweight, other birth characteristics, and schizophrenia. Twin pairs discordant for schizophrenia will also control for unmeasured genetic and shared environmental effects. Prospectively filed obstetric records were used for a cohort analysis of 11,360 same-sexed twins, and within–twin pair analyses were conducted on 90 twin pairs discordant for schizophrenia. The results from the cohort study showed that low birthweight (less than or equal to 1999 grams; odds ratio [OR] 1.67, 95% confidence interval [CI] 0.88–3.14 and 2000–2299 grams; OR 1.79, 95% CI 1.07–3.01) and small head circumference (less than or equal to 31.5 cm; OR 1.61, 95% CI 1.03–2.51) were associated with later development of schizophrenia. The associations remained in the within-pair analyses. The association between low birthweight and schizophrenia is partly a function of reduced fetal growth. Fetal growth restriction seems to be associated with risk of schizophrenia independently of familial factors.
Education Issues; Twin Study Summaries; Famous Twin Babies and Famous Twins
Authors: Segal Nancy L.
Published: May 2007

Two educational issues of special relevance to twins and their families are reviewed. The first concerns newly passed legislation in the state of Minnesota allowing multiple birth parents to decide if their children should be placed in the same or separate classrooms. The second concerns a professor's accusations of identical twins' academic misconduct, based upon the twins' similar test performance. Next, reviews of timely research in the areas of religiosity, disease, conjoined twinning and autism are presented. Finally, some recent events featuring well-known twins are presented.
The Heritability of Telomere Length Among the Elderly and Oldest-Old
Authors: Bischoff Claus , Graakjaer Jesper , Petersen Hans Christian , Hjelmborg Jacob v. B. , Vaupel James W. , Bohr Vilhelm , Koelvraa Steen , Christensen Kaare
Published: May 2007

A tight link exists between telomere length and both population doublings of a cell culture and age of a given organism. The more population doublings of the cell culture or the higher the age of the organism, the shorter the telomeres. The proposed model for telomere shortening, called the end replication problem, explains why the telomere erodes at each cellular turnover. Telomere length is regulated by a number of associated proteins through a number of different signaling pathways. The determinants of telomere length were studied using whole blood samples from 287 twin pairs aged 73 to 95 years. Structural equation models revealed that a model including additive genetic effects and non- shared environment was the best fitting model and that telomere length was moderately heritable, with an estimate that was sensitive to the telomere length standardization procedure. Sex-specific analyses showed lower heritability in males, although not statistically significant, which is in line with our earlier finding of a sex difference in telomere dynamics among the elderly and oldest-old.
Subjective Wellbeing and Sleep Problems: A Bivariate Twin Study
Authors: Nes Ragnhild B. , Røysamb Espen , Reichborn-Kjennerud Ted , Tambs Kristian , Harris Jennifer R.
Published: May 2007

The relationship between subjective wellbeing (SWB) and self-reported sleep problems was investigated in a cohort of Norwegian twins aged 18 to 31 years. Questionnaire data from 8045 same- and opposite-sex twins were analyzed using structural equation modeling to explore the relative effects of genetic and environmental influences on phenotypic variance and covariance. Special attention was paid to sex-specific effects. The correlation between the phenotypes was estimated to be −.43. Univariate analyses indicated considerable genetic influences for both SWB and sleep problems, for male and female twins alike. The best fitting bivariate model specified additive genetic and individual environmental factors for both phenotypes, and nonadditive genetic effects for sleep problems, with no sex-specific effects. Genetic and environmental effects accounted for 60% and 40% of the phenotypic correlation, respectively. Additive genetic factors affecting the two phenotypes were correlated (−.85), suggesting that part of the genetic effects that positively influence SWB also protect against sleep problems. In conclusion, the results indicate considerable overlap in genetic etiology for SWB and sleep problems, for males and females alike.
Eating Disorders: From Twin Studies to Candidate Genes and Beyond
Authors: Slof-Op ‘t Landt Margarita C. T. , van Furth Eric F. , Meulenbelt Ingrid , Slagboom P. Eline , Bartels Meike , Boomsma Dorret I. , Bulik Cynthia M.
Published: May 2007

Substantial effort has been put into the exploration of the biological background of eating disorders, through family, twin and molecular genetic studies. Family studies have shown that anorexia (AN) and bulimia nervosa (BN) are strongly familial, and that familial etiologic factors appear to be shared by both disorders. Twin studies often focus on broader phenotypes or subthreshold eating disorders. These studies consistently yielded moderate to substantial heritabilities. In addition, there has been a proliferation of molecular genetic studies that focused on Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) AN and BN. Seven linkage regions have been identified in genome-wide screens. Many genetic association studies have been performed, but no consistent association between a candidate gene and AN or BN has been reported. Larger genetic association studies and collaborations are needed to examine the involvement of several candidate genes and biological pathways in eating disorders. In addition, twin studies should be designed to assist the molecular work by further exploring genetic determinants of endophenotypes, evaluating the magnitude of contribution to liability of measured genotypes as well as environmental risk factors related to eating disorders. In this manner twin and molecular studies can move the field forward in a mutually informative way.