bluuebunny/crossref_metadata_2025_split huggingface dataset:
Highly endemic hepatitis B infection in rural Vietnam
Authors: Nguyen Van Thi‐Thuy , McLaws Mary‐Louise , Dore Gregory J 
Published: July 2007

AbstractBackground and Aim:  Hepatitis B is a major public health problem in Vietnam; however, estimates of the prevalence of hepatitis B virus (HBV) and hepatitis delta virus (HDV), and risk factors in rural Vietnam are limited. The aim of this study was to determine HBV and HDV prevalence, and identify risk factors for HBV infection.Methods:  A cross‐sectional seroprevalence study was undertaken in two rural districts in Thai Binh province. The study population was randomly selected using multistage sampling. Demographic and behavioral risk information and serological samples were obtained from 837 participants.Results:  Mean age was 42.3 years ± 15.8 (range, 16–82 years), and 50.8% were female. Prevalence of anti‐HBV core antibody (anti‐HBc) and hepatitis B virus surface antigen (HBsAg) was 68.2% and 19.0%, respectively, and hepatitis B e antigen HBeAg was detected in 16.4% of the HBsAg‐positive group. Prevalence of HDV was 1.3% in the HBsAg‐positive group. Factors associated with HBV infection (anti‐HBc or HBsAg positive) were age 60 years or older (OR, 3.82; 95% CI, 1.35–10.80; P = 0.01), residence in Vu Thu district (OR, 3.00; 95% CI, 2.16–4.17; P < 0.0001), hospital admission (OR, 2.34; 95% CI, 1.33–4.13; P = 0.003) and history of acupuncture (OR, 2.01; 95% CI, 1.29–3.13; P = 0.002). Household contact with a person with liver disease (OR, 2.13; 95% CI, 1.29–3.52; P = 0.003), reuse of syringes (OR, 1.81; 95% CI, 1.25–2.62; P = 0.002) and sharing of razors (OR, 1.69; 95% CI, 1.03–2.79; P = 0.04) were independent predictors of HBsAg positivity. Alanine aminotransferase (ALT) level was elevated (>40 IU/L) in 43% of the HBsAg‐positive group; proportion elevated was higher in HBeAg‐positive (65%) compared with HBeAg‐negative (39%) individuals in this group (P = 0.02).Conclusion:  Hepatitis B virus infection is highly endemic in rural Vietnam. Poor infection control activities in health‐care settings contribute to high HBV prevalence in this region. Universal HBV infant vaccination and improved infection control procedures are required for improved HBV control in Vietnam.
MRI findings in the lumbar spines of asymptomatic, adolescent, elite tennis players
Authors: Alyas F , Turner M , Connell D 
Published: July 2007

Objective:To describe magnetic resonance imaging (MRI) findings in the lumbar spine in asymptomatic elite adolescent tennis players, to serve as the baseline for a future prospective longitudinal cohort study.Design:Observational study.Setting:Institutional, national tennis centre.Participants:33 asymptomatic elite adolescent tennis players, mean (SD) age, 17.3 (1.7) years (18 male, 15 female).Methods:Sagittal T1, T2, STIR, and axial T2 weighted MRI images were reviewed for the presence of abnormalities by two radiologists in consensus. Abnormalities included disc degeneration, disc herniation, pars lesions (fracture or stress reaction), and facet joint arthropathy.Results:Five players (15.2%) had a normal MRI examination and 28 (84.8%) had an abnormal examination. Nine players showed pars lesions (10 lesions; one at two levels) predominately at the L5 level (9/10, L5; 1/10, L4). Three of the 10 lesions were complete fractures; two showed grade 1 and one grade 2 spondylolisthesis, both of which resulted in moderate narrowing of the L5 exit foramen. There were two acute and five chronic stress reactions of the pars. Twenty three patients showed signs of early facet arthropathy occurring at L5/S1 (15/29 joints) and L4/5 (12/29 joints). These were classified as mild degeneration (20/29) and moderate degeneration (9/29), with 20/29 showing sclerosis and 24/29 showing hypertrophy of the facet joint. Synovial cysts were identified in 14 of the 29 joints. Thirteen players showed disc desiccation and disc bulging (mild in 13; moderate in two) most often at L4/5 and L5/S1 levels (12 of 15 discs).Conclusions:Abnormalities were frequent, predominately in the lower lumbar spine, almost exclusively at L4/5 and L5/S1 levels. Pars injuries and facet joint arthroses were relatively common.
PROPERTIES OF THE CASCADED LATTICE BOLTZMANN AUTOMATON
Authors: GEIER MARTIN , GREINER ANDREAS , KORVINK JAN G. 
Published: July 2007

The theory of the lattice Boltzmann automaton is based on a moment transform which is not Galilean invariant. It is explained how the central moments transform, used in the cascaded lattice Boltzmann method, overcomes this problem by choosing the center of mass coordinate system as the frame of reference. Galilean invariance is restored and the form of the kinetic theory is unaffected. Conservation laws are not compromised by the high order polyinomials in the equilibrium distribution arising from the central moment transform. Two sources of instabilities in lattice Boltzmann simulations are discussed: negative numerical viscosity due to insufficient Galilean invariance and aliasing. The cascaded lattice Boltzmann automaton overcomes both problems. It is discussed why aliasing is unavoidable in lattice Boltzmann methods that rely on a single relaxation time. An appendix lists the complete scattering operator of the D2Q9 cascaded lattice Boltzmann automaton.
The Relationship between the Outcome of Studies of Autologous Chondrocyte Implantation and the Presence of Commercial Funding
Authors: Lubowitz James H. , Appleby David , Centeno Joseph M. , Woolf Shane K. , Reid John B. 
Published: July 2007

Background Autologous chondrocyte implantation (ACI) is an expensive treatment option for focal cartilage defects, and commercial funding of research is associated with a study reaching a positive conclusion. The purpose of this analysis is to compare outcomes (and levels of evidence) between published ACI outcome studies that were commercially funded and studies that were not commercially funded. Hypothesis Commercially funded ACI literature could be commercially biased. Study Design Comparative meta-analysis. Methods MEDLINE was searched for human, knee, ACI, nonmembrane, English language, and clinical outcome studies. Studies were evaluated with regard to funding status (commercially funded or not commercially funded), outcomes, and levels of evidence. Outcomes and levels of evidence were evaluated and compared for commercially funded studies versus those that were not commercially funded. Results Twenty-three studies were included; 16 (70%) were commercially funded. Pooled clinical outcome measures data were not significantly different (Lysholm, Modified Cincinnati, patient-reported Cincinnati, Tegner, pain Visual Analog Scale) when comparing commercially funded studies with those that were not commercially funded. However, distribution of levels of evidence was significantly lower (P = .045) for commercially funded studies. Conclusion Reassuringly, commercial funding of ACI studies did not result in a difference in published clinical outcomes versus those that were not commercially funded. However, the lower levels of evidence of commercially funded studies suggests that commercially funded ACI studies may be of less value to surgeons desiring to practice evidence-based medicine, and, in the future, commercial entities funding medical research could selectively fund studies of the highest levels of evidence.
Protease-activated receptor-4 inhibition protects from multiorgan failure in a murine model of systemic inflammation
Authors: Slofstra Sjoukje H. , Bijlsma Maarten F. , Groot Angelique P. , Reitsma Pieter H. , Lindhout Theo , ten Cate Hugo , Spek C. Arnold 
Published: July 2007

AbstractCoagulation proteases may act as cell signaling molecules via protease-activated receptor (PAR) cleavage, subsequently affecting cellular and inflammatory responses. Activation of PARs in the setting of systemic inflammation and disseminated intravascular coagulation (DIC) might thus exacerbate the inflammatory response contributing to tissue and organ damage. To investigate the role of PAR-4 in these processes, we subjected mice to a model of systemic inflammation and DIC (Shwartzman reaction) in the absence or presence of a cell-penetrating pepducin antagonist of PAR-4 (P4pal-10). P4pal-10 dose-dependently diminished the severity of endotoxemia and preserved liver, kidney, as well as lung function. Moreover, systemic inflammation and local (neutrophilic) inflammatory responses were attenuated. In vitro migration assays and P4pal-10 treatment in neutropenic mice suggest an essential role for neutrophils in PAR-4–mediated pathology. P4pal-10 treatment of thrombocytopenic mice excluded the involvement of platelets in this phenomenon. These results uncover an important role for PAR-4 in the Shwartzman reaction and suggest that inhibition of PAR-4 signaling in neutrophils could be protective in systemic inflammation and DIC.
Anti-inflammatory effects of Lactobacillus casei BL23 producing or not a manganese-dependant catalase on DSS-induced colitis in mice
Authors: Rochat Tatiana , Bermúdez-Humarán Luis , Gratadoux Jean-Jacques , Fourage Christel , Hoebler Christine , Corthier Gérard , Langella Philippe 
Published: July 2007

Abstract

Background
Human immune cells generate large amounts of reactive oxygen species (ROS) throughout the respiratory burst that occurs during inflammation. In inflammatory bowel diseases, a sustained and abnormal activation of the immune system results in oxidative stress in the digestive tract and in a loss of intestinal homeostasis. We previously showed that the heterologous production of the Lactobacillus plantarum ATCC14431 manganese-dependant catalase (MnKat) in Lb. casei BL23 successfully enhances its survival when exposed to oxidative stress. In this study, we evaluated the preventive effects of this antioxidative Lb. casei strain in a murine model of dextran sodium sulfate (DSS)-induced moderate colitis.

Results
Either Lb. casei BL23 MnKat- or MnKat+ was administered daily to mice treated with DSS for 10 days. In contrast to control mice treated with PBS for which DSS induced bleeding diarrhea and mucosal lesions, mice treated with both Lb. casei strains presented a significant (p < 0.05) reduction of caecal and colonic inflammatory scores.

Conclusion
No contribution of MnKat to the protective effect from epithelial damage has been observed in the tested conditions. In contrast, these results confirm the high interest of Lb. casei as an anti-inflammatory probiotic strain.
Aerodynamic force generation, performance and control of body orientation during gliding in sugar gliders (Petaurus breviceps)
Authors: Bishop Kristin L. 
Published: July 2007

SUMMARYGliding has often been discussed in the literature as a possible precursor to powered flight in vertebrates, but few studies exist on the mechanics of gliding in living animals. In this study I analyzed the 3D kinematics of sugar gliders (Petaurus breviceps) during short glides in an enclosed space. Short segments of the glide were captured on video, and the positions of marked anatomical landmarks were used to compute linear distances and angles, as well as whole body velocities and accelerations. From the whole body accelerations I estimated the aerodynamic forces generated by the animals. I computed the correlations between movements of the limbs and body rotations to examine the control of orientation during flight. Finally, I compared these results to those of my earlier study on the similarly sized and distantly related southern flying squirrel (Glaucomys volans). The sugar gliders in this study accelerated downward slightly (1.0±0.5 m s–2), and also accelerated forward (2.1±0.6 m s–2) in all but one trial, indicating that the body weight was not fully supported by aerodynamic forces and that some of the lift produced forward acceleration rather than just balancing body weight. The gliders used high angles of attack (44.15±3.12°), far higher than the angles at which airplane wings would stall, yet generated higher lift coefficients (1.48±0.18) than would be expected for a stalled wing. Movements of the limbs were strongly correlated with body rotations,suggesting that sugar gliders make extensive use of limb movements to control their orientation during gliding flight. In addition, among individuals,different limb movements were associated with a given body rotation,suggesting that individual variation exists in the control of body rotations. Under similar conditions, flying squirrels generated higher lift coefficients and lower drag coefficients than sugar gliders, yet had only marginally shallower glides. Flying squirrels have a number of morphological specializations not shared by sugar gliders that may help to explain their greater lift generating performance.
Females do it better. Individual recognition experiments reveal sexual dimorphism in Lemur catta (Linnaeus 1758) olfactory motivation and territorial defence
Authors: Palagi Elisabetta , Dapporto Leonardo 
Published: July 2007

SUMMARY
In this paper, we aim at demonstrating individual recognition of female genital marking in Lemur catta. By gas chromatography and behavioural trials we verified the occurrence of the three components of recognition systems. We showed that each female has a unique chemical signature(expression component), and males and females perceive female individuality(perception component). To verify the presence of the action component (the last component of recognition systems), we designed a bioassay based on territorial competition to verify the functional response to female odours. Only females identified other females on the basis of their scents. The lack of a territorial functional response by males to female secretions may not indicate a male inability to identify females by their scents. In fact, sexual dimorphism in motivation and territorial defence may explain the response by males in the functional experiment. Actually, game theory predicts that males defend their own territories more vigorously against males compared with females. Therefore, the result of individual recognition bioassays of female odours may open interesting scenarios in the evaluation of the territorial defence investment across the different sex combinations.
Plasticity in arthropod cryotypes
Authors: Hawes T. C. , Bale J. S. 
Published: July 2007

SUMMARYLow-temperature acclimation and acclimatization produce phenotypic changes in arthropods at multiple levels of biological organization from the molecular to the behavioural. The role and function of plasticity – where a constitutive, reversible change occurs in the phenotype in response to low temperature – may be partitioned hierarchically at evolutionary scales according to cryoprotective strategy, at macrophysiological scales according to climatic variability, and at meso- and micro-scales according to ecological niche and exposure. In correspondence with these scales (which are interdependent rather than mutually exclusive), a hierarchical typology of interaction between thermal history and organism is proposed, descending,respectively, from what we define as `cryotype' (class of cryoprotective strategy) to genotype and, ultimately, phenotype. Alternative (and sometimes complementary) strategies to plasticity include specialization,generalization, bet-hedging, cross-resistance and convergence. The transition of cryotypes from basal to derived states is a continuum of trait optimization, involving the fixation of plasticity and/or its alternatives.
Blood oxygen depletion during rest-associated apneas of northern elephant seals (Mirounga angustirostris)
Authors: Stockard T. K. , Levenson D. H. , Berg L. , Fransioli J. R. , Baranov E. A. , Ponganis P. J. 
Published: July 2007

SUMMARYBlood gases (PO2, PCO2, pH), oxygen content, hematocrit and hemoglobin concentration were measured during rest-associated apneas of nine juvenile northern elephant seals. In conjunction with blood volume determinations, these data were used to determine total blood oxygen stores, the rate and magnitude of blood O2 depletion, the contribution of the blood O2 store to apneic metabolic rate, and the degree of hypoxemia that occurs during these breath-holds. Mean body mass was 66±9.7 kg (± s.d.); blood volume was 196±20 ml kg–1; and hemoglobin concentration was 23.5±1.5 g dl–1. Rest apneas ranged in duration from 3.1 to 10.9 min. Arterial PO2 declined exponentially during apnea, ranging between a maximum of 108 mmHg and a minimum of 18 mmHg after a 9.1 min breath-hold. Venous PO2 values were indistinguishable from arterial values after the first minute of apnea; the lowest venous PO2 recorded was 15 mmHg after a 7.8 min apnea. O2 contents were also similar between the arterial and venous systems, declining linearly at rates of 2.3 and 2.0 ml O2 dl–1 min–1, respectively, from mean initial values of 27.2 and 26.0 ml O2 dl–1. These blood O2 depletion rates are approximately twice the reported values during forced submersion and are consistent with maintenance of previously measured high cardiac outputs during rest-associated breath-holds. During a typical 7-min apnea, seals consumed, on average, 56% of the initial blood O2 store of 52 ml O2 kg–1; this contributed 4.2 ml O2 kg–1 min–1to total body metabolic rate during the breath-hold. Extreme hypoxemic tolerance in these seals was demonstrated by arterial PO2 values during late apnea that were less than human thresholds for shallow-water blackout. Despite such low PO2s, there was no evidence of significant anaerobic metabolism, as changes in blood pH were minimal and attributable to increased PCO2. These findings and the previously reported lack of lactate accumulation during these breath-holds are consistent with the maintenance of aerobic metabolism even at low oxygen tensions during rest-associated apneas. Such hypoxemic tolerance is necessary in order to allow dissociation of O2 from hemoglobin and provide effective utilization of the blood O2 store.
Methodology for Rapid Determination of Pozzolanic Activity of Materials
Authors: Dalinaidu A. , Das B. B. , Singh D. N. 
Published: July 2007

Abstract
Determination of pozzolanic activity, and in particular lime reactivity, of various materials such as fly ash, cenospheres, blast furnace slag, etc., is quite essential for their efficient application in cement and concrete. It also plays an important role in the selection of the material as a stabilizer in various environmental cleanup projects, such as heavy metal retention and waste immobilization strategies. Though ASTM C 311, ASTM C 593, and IS 1727 are being followed to determine pozzolanic activity of different materials, they are quite time consuming. This necessitates development of a methodology that can be employed for determining the pozzolanic activity of different materials, quite rapidly and easily. With this in view, a methodology that indirectly estimates pozzolanic activity of different materials, by measuring electrical conductivity of their mixture in partially saturated lime solution, has been developed and its details are presented in this paper.
Masonry Repairs at Cheshire Mill No. 1, Harrisville, New Hampshire
Authors: Willett Linda , O’Connor Frederick 
Published: July 2007

Abstract
The first modern-day application of Rosendale natural cement mortars in a significant historic restoration is described. The background of Cheshire Mill No. 1 in Historic Harrisville, New Hampshire, the analyses of its original mortar composition, and the successful use of natural cement for in-kind repointing are detailed.
Modeling the Interaction of Helium with Dislocations and Grain Boundaries in Alpha-Iron
Authors: Heinisch H. L. , Gao F. , Kurtz R. J. 
Published: July 2007

Abstract
Helium is a ubiquitous impurity in nuclear materials that can have significant deleterious effects on mechanical properties, including deformation and fracture. To determine ways to mitigate the effects of helium it is necessary to understand the behavior of helium with respect to its interaction with various microstructural features. Toward that end, we have employed molecular statics, molecular dynamics, and the dimer method of potential surface mapping to study the fate of helium in the vicinity of dislocations and grain boundaries in alpha-iron. Even at very low temperatures interstitial helium atoms can migrate to dislocations and grain boundaries, where they are strongly bound. The binding energies of helium to these microstructural features relative to the perfect crystal and the migration energies of helium diffusing within them have a strong correlation to the excess atomic volume that exists in these extended defects. Helium atom migration energies within the dislocations and grain boundaries studied are in the range of 0.4–0.5 eV. Helium “kick out” mechanisms have been identified within dislocations and grain boundaries by which interstitial helium atoms replace an Fe lattice atom, creating a stable He-vacancy complex that may be a nucleation site for an He bubble.
Management of teenage pregnancy
Authors: Horgan Richard P , Kenny Louise Clare 
Published: July 2007

Key content

The United Kingdom has the highest teenage pregnancy rate in Western Europe.
Risk factors include socioeconomic deprivation, low educational achievement and having teenage parents.
Adverse outcomes associated with teenage pregnancy include premature delivery, infants being small for gestational age, low birthweight and increased neonatal mortality.
Associated risks include high rates of sexually transmitted infections, alcohol and substance misuse, smoking and poor diet.
Attendance at antenatal care is generally poor and teenagers may present late, therefore, it is important to tailor care to their individual needs.

Learning objectives

To learn about current guidance and policies.
To know about the risk factors for teenage pregnancy, adverse outcomes and associated risks.
To learn about the management of teenage pregnancy with particular reference to prevention.

Ethical issues

When is it necessary to obtain parental consent for termination of pregnancy or to prescribe contraception in girls aged less than 16 years of age?
Why do some teenagers see pregnancy as a positive life event?

Please cite this article as: Horgan RP, Kenny LC. Management of teenage pregnancy. The Obstetrician & Gynaecologist 2007;9:153–158.