J/psi production as a function of charged particle multiplicity in pp collisions at root s=7 TeV

The ALICE Collaboration reports the measurement of the relative J/psi yield as a function of charged particle pseudorapidity density dN(ch)/d eta in pp collisions at root s = 7 TeV at the LHC. J/psi particles are detected for p(t) > 0, in the rapidity interval vertical bar y vertical bar < 0.9 via decay into e(+)e(-), and in the interval 2.5 < y < 4.0 via decay into mu(+)/mu(-) pairs. An approximately linear increase of the J/psi yields normalized to their event average (dN(J/psi)/dy)/(dN(J/psi)/dy) with (dN(ch)/c eta)/(dN(ch)/d eta) is observed in both rapidity ranges, where dN(ch)/d eta is measured within vertical bar eta vertical bar < 1 and p(t) > 0. In the highest multiplicity interval with (dN(ch)/d eta)(bin)) = 24.1, corresponding to four times the minimum bias multiplicity density, an enhancement relative to the minimum bias J/psi yield by a factor of about 5 at 2.5 < y <4 (8 at vertical bar y vertical bar < 0.9) is observed. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.

Association of laser phototherapy with PRP improves healing of bisphosphonate-related osteonecrosis of the jaws in cancer patients: A preliminary study

The aim of this study was to compare retrospectively the effect of three different treatments on the healing outcome of bisphosphonate-related osteonecrosis of the jaws (BRONJ) in cancer patients. Twenty-two cancer patients were treated for BRONJ with one of the following protocols: clinical (pharmacological therapy), surgical (pharmacological plus surgical therapy), or PRP plus LPT (pharmacological plus surgical plus platelet rich plasma (PRP) plus laser phototherapy (LPT). The laser treatment was applied with a continuous diode laser (InGaAlP, 660 nm) using punctual and contact mode, 40 mW, spot size 0.042 cm(2), 6 J/cm(2) (6 s) and total energy of 0.24 J per point. The irradiations were performed on the exposed bone and surrounding soft tissue. The analysis of demographic data and risk factors was performed by gathering the following information: age, gender, primary tumor, bisphosphonate (BP) used, duration of BP intake, history of chemotherapy, use of steroids, and medical history of diabetes. The association between the current state of BRONJ (with or without bone exposure) and other qualitative variables was determined using the chi-square or Fisher's exact test. In all tests, the significance level adopted was 5%. Most BRONJ lesions occurred in the mandible (77%) after tooth extraction (55%) and in women (72%). A significantly higher percentage of patients reached the current state of BRONJ without bone exposure (86%) in the PPR plus LPT group than in the pharmacological (0%) and surgical (40%) groups after 1-month follow-up assessment. These results suggest that the association of pharmacological therapy and surgical therapy with PRP plus LPT significantly improves BRONJ healing in oncologic patients. Although prospective studies with larger sample sizes are still needed, this preliminary study may be used to inform a better-designed future study. (C) 2011 Elsevier Ltd. All rights reserved.

Mini-Mental State Examination performance in frail, pre-frail, and non-frail community dwelling older adults in Ermelino Matarazzo, Sao Paulo, Brazil

Background: Frailty in older adults is a multifactorial syndrome defined by low metabolic reserve, less resistance to stressors, and difficulty in maintaining organic homeostasis due to cumulative decline of multiple physiological systems. The relationship between frailty and cognition remains unclear and studies about Mini-Mental State Examination (MMSE) performance and frailty are scarce. The objective was to examine the association between frailty and cognitive functioning as assessed by the MMSE and its subdomains. Methods: A cross-sectional population-based study (FIBRA) was carried out in Ermelino Matarazzo, a poor subdistrict of the city of Sao Paulo, Brazil. Participants were 384 community dwelling older adults, 65 years and older who completed the MMSE and a protocol to assess frailty criteria as described in the Cardiovascular Health Study (CHS). Results: Frail older adults had significantly worse performance on the MMSE (p < 0.001 for total score). Linear regression analyses showed that the MMSE total score was influenced by age (p < 0.001), education (p < 0.001), family income (p < 0.001), and frailty status (p < 0.036). Being frail was associated more significantly with worse scores in Time Orientation (p < 0.004) and Immediate Memory (p < 0.001). Conclusions: Our data suggest that being frail is associated with worse cognitive performance, as assessed by the MMSE. It is recommended that the assessment of frail older adults should include the investigation of their cognitive status.

Hepatitis B virus infection in Haemodialysis Centres from Santa Catarina State, Southern Brazil. Predictive risk factors for infection and molecular epidemiology

Abstract Background Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil. Methods This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units. Results Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection. Conclusions Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.

A note on the use of the generalized odds ratio in meta-analysis of association studies involving bi- and tri-allelic polymorphisms

Abstract Background The generalized odds ratio (GOR) was recently suggested as a genetic model-free measure for association studies. However, its properties were not extensively investigated. We used Monte Carlo simulations to investigate type-I error rates, power and bias in both effect size and between-study variance estimates of meta-analyses using the GOR as a summary effect, and compared these results to those obtained by usual approaches of model specification. We further applied the GOR in a real meta-analysis of three genome-wide association studies in Alzheimer's disease. Findings For bi-allelic polymorphisms, the GOR performs virtually identical to a standard multiplicative model of analysis (e.g. per-allele odds ratio) for variants acting multiplicatively, but augments slightly the power to detect variants with a dominant mode of action, while reducing the probability to detect recessive variants. Although there were differences among the GOR and usual approaches in terms of bias and type-I error rates, both simulation- and real data-based results provided little indication that these differences will be substantial in practice for meta-analyses involving bi-allelic polymorphisms. However, the use of the GOR may be slightly more powerful for the synthesis of data from tri-allelic variants, particularly when susceptibility alleles are less common in the populations (≤10%). This gain in power may depend on knowledge of the direction of the effects. Conclusions For the synthesis of data from bi-allelic variants, the GOR may be regarded as a multiplicative-like model of analysis. The use of the GOR may be slightly more powerful in the tri-allelic case, particularly when susceptibility alleles are less common in the populations.

Association of postalimentary lipemia with atherosclerotic manifestations

We identified different lipemic and metabolic responses after the ingestion of a standardized meal by healthy adults and related them to atherosclerotic markers. Samples from 60 normolipidemic adults were collected before and after a liquid meal (40 g fat/m² body surface) at 0, 2, 4, 6, and 8 h for measurements of lipids, free fatty acids (FFA), insulin, cholesteryl ester transfer protein (CETP), autoantibodies to epitopes of oxidized LDL (oxLDL Ab), lipolytic activities, and apolipoprotein E polymorphism. Mean carotid intima-media thickness (cIMT) was determined by Doppler ultrasound. The volunteers were classified into early (N = 39) and late (N = 31) triacylglycerol (TAG) responders to the test meal. Late responders showed lower HDL cholesterol concentration at fasting and in the TAG peak, lower insulin and higher FFA concentrations compared to early responders. Multivariate regression analyses showed that mean cIMT was associated with gender (male) and age in early responders and by cholesterol levels at the 6th hour in late responders. oxLDL Ab were explained by lipoprotein lipase and negatively by hepatic lipase and oxLDL Ab (fasting period) by CETP (negative) and FFA (positive). This study is the first to identify a postalimentary insulin resistance state, combined with a reduced CETP response exclusively among late responders, and the identification of the regulators of postalimentary atherogenicity. Further research is required to determine the metabolic mechanisms described in the different postalimentary phenotypes observed in this study, as well as in different pathological states, as currently investigated in our laboratory.

Association between nonnutritive sucking habits and anterior open bite in the deciduous dentition of Japanese-Brazilians

OBJECTIVE: Assess the association between nonnutritive sucking habits and anterior open bite in the deciduous dentition of Japanese-Brazilian children. METHODS: 410 children of Japanese origin were assessed, 206 boys and 204 girls, between 2 and 6 years of age, in schools in São Paulo State, Brazil. Questionnaires concerning their nonnutritive sucking habits were sent to their legal guardians. Chi-square tests (p<0.05) were applied to assess the association between nonnutritive sucking habits and anterior open bite, and the logistic regression test to obtain the relative risk. RESULTS: The prevalence of sucking habits found in the sample was of 44.6% and for the anterior open bite, 4.4%. There was a statistically significant association between anterior open bite and sucking habits (O.R.=10.77), persistence of sucking habits from 2 to 4 years old (O.R.=22.06), and the persistence of sucking habits from 4 to 6 years old (O.R.=17.31). As for the interruption period of the habit, the group that had interrupted the habit for a period equal or inferior to six months showed an increased prevalence of open bite compared to the group without this habit or in which the habit was interrupted for more than six months. CONCLUSION: Japanese-Brazilian children that had sucking habits have greater chance of acquiring anterior open bite in the deciduous dentition.

Vegetation mapping in an area of Ombrophilous Dense Forest at Parque Estadual da Serra do Mar, São Paulo State, Brazil, and floristic composition of the tree component of some physiognomies*

This study aimed to map phytophysiognomies of an area of Ombrophilous Dense Forest at Parque Estadual da Serra do Mar and characterize their floristic composition. Photointerpretation of aerial photographs in scale of 1:35,000 was realized in association with field work. Thirteen physiognomies were mapped and they were classified as Montane Ombrophilous Dense Forest, Alluvial Ombrophilous Dense Forest or Secondary System. Three physiognomies identified at Casa de Pedra streamlet's basin were studied with more details. Riparian forest (RF), valley forest (VF), and hill forest (HF) presented some floristic distinction, as confirmed by Detrended Correspondence Analysis (DCA) and Indicator Species Analysis (ISA) conducted here. Anthropic or natural disturbances and heterogeneity of environmental conditions may be the causes of physiognomic variation in the vegetation of the region. The results presented here may be useful to decisions related to management and conservation of Núcleo Santa Virgínia forests, in general.

Dental caries associated factors in 12 year-old schoolchildren from a municipality in the state of São Paulo, Brazil

Objective To analyze the possible association between dental caries, fluorosis and the need for treatment in 12 year-old schoolchildren and the socioeconomic conditions of parents/guardians in the city of Franca, in the state of São Paulo. Methods A random sample of schoolchildren aged 12 was obtained from the school records in Franca, using a systematic random technique. The epidemiological survey was carried out by a single calibrated examiner, on 258 public and private schoolchildren in order to obtain the prevalence of dental caries, the need for treatment and the severity of dental fluorosis. Parents/guardians were also interviewed to assess their socioeconomic conditions (education and per capita income). We used multiple correlation analysis to investigate associations between category variables. Results It was possible to identify two distinct groups, with associations between the variables: the first group, represented by schoolchildren with average prevalence of caries, need for treatment, low level of parental education and income; and a second group represented by schoolchildren with low prevalence of caries, no need for treatment, high parental education and income. The two dimensions explained approximately 35% of total inertia. The factors within each group are related. Conclusion High income and parental education are associated with the low prevalence of dental caries but there is no association with dental fluorosis.

Association between IL8 haplotypes and pathogen levels in chronic periodontitis

Chronic periodontitis (CP) is considered to be a multifactorial disease influenced by microbial and genetic factors. The aim of the present study was to investigate whether the genetic susceptibility to CP in individuals with the IL8 ATC/TTC haplotype is associated with subgingival levels of periodontopathogens. Sixty-five individuals, grouped according to the presence (n=28) or absence (n=37) of the IL8 haplotype, were evaluated. After clinical periodontal evaluation, each group was subdivided according to the presence (CP) or absence (H) of periodontitis. Four subgingival samples were obtained from CP and two samples per subject from H patients. The levels and proportions of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were analyzed using quantitative real-time polymerase chain reaction (q-PCR). No differences were found in the proportion of periodontopathogenic bacteria between groups with the presence or absence of the IL8 haplotype. However, in the CP groups, the levels of periodontopathogens were significantly higher in the individuals withou the IL8 haplotype than in the individuals with the IL8 haplotype. These results suggest that periodontal destruction may occur in patients who are considered to be genetically susceptible to CP with a lower microbial challenge because of the presence of the IL8 ATC/TTC haplotype than in patients without this haplotype.

The formation of AlF by radiative association

The formation of the aluminium monofluoride molecule AlF by radiative association of the Al and F atoms is estimated. The radiative association of Al(2P) and F(2P) atoms is found to be dominated by the approach along theA1 potential energy curve accompanied by spontaneous emission into theX1 + ground state of the AlF. For temperatures ranging from 300 to 14 000 K, the rate coefficients are found to vary from 1.35×10−17 to 9.31×10−16 cm3 s−1, respectively.These values indicate that only a small amount of AlF molecules can be formed by radiative association in the inner envelope of carbon-rich stars and other hostile environments.

Longitudinal bar buckling behavior

Reinforced concrete columns might fail because of buckling of the longitudinal reinforcing bar when exposed to earthquake motions. Depending on the hoop stiffness and the length-over-diameter ratio, the instability can be local (in between two subsequent hoops) or global (the buckling length comprises several hoop spacings). To get insight into the topic, an extensive literary research of 19 existing models has been carried out including different approaches and assumptions which yield different results. Finite element fiberanalysis was carried out to study the local buckling behavior with varying length-over-diameter and initial imperfection-over-diameter ratios. The comparison of the analytical results with some experimental results shows good agreement before the post buckling behavior undergoes large deformation. Furthermore, different global buckling analysis cases were run considering the influence of different parameters; for certain hoop stiffnesses and length-over-diameter ratios local buckling was encountered. A parametric study yields an adimensional critical stress in function of a stiffness ratio characterized by the reinforcement configuration. Colonne in cemento armato possono collassare per via dell’instabilità dell’armatura longitudinale se sottoposte all’azione di un sisma. In funzione della rigidezza dei ferri trasversali e del rapporto lunghezza d’inflessione-diametro, l’instabilità può essere locale (fra due staffe adiacenti) o globale (la lunghezza d’instabilità comprende alcune staffe). Per introdurre alla materia, è proposta un’esauriente ricerca bibliografica di 19 modelli esistenti che include approcci e ipotesi differenti che portano a risultati distinti. Tramite un’analisi a fibre e elementi finiti si è studiata l’instabilità locale con vari rapporti lunghezza d’inflessione-diametro e imperfezione iniziale-diametro. Il confronto dei risultati analitici con quelli sperimentali mostra una buona coincidenza fino al raggiungimento di grandi spostamenti. Inoltre, il caso d’instabilità globale è stato simulato valutando l’influenza di vari parametri; per certe configurazioni di rigidezza delle staffe e lunghezza d’inflessione-diametro si hanno ottenuto casi di instabilità locale. Uno studio parametrico ha permesso di ottenere un carico critico adimensionale in funzione del rapporto di rigidezza dato dalle caratteristiche dell’armatura.

Spinal cord injury: assessment of autonomic state-dependent control of cardiovascular system and body core temperature

Spinal cord injury (SCI) results not only in paralysis; but it is also associated with a range of autonomic dysregulation that can interfere with cardiovascular, bladder, bowel, temperature, and sexual function. The entity of the autonomic dysfunction is related to the level and severity of injury to descending autonomic (sympathetic) pathways. For many years there was limited awareness of these issues and the attention given to them by the scientific and medical community was scarce. Yet, even if a new system to document the impact of SCI on autonomic function has recently been proposed, the current standard of assessment of SCI (American Spinal Injury Association (ASIA) examination) evaluates motor and sensory pathways, but not severity of injury to autonomic pathways. Beside the severe impact on quality of life, autonomic dysfunction in persons with SCI is associated with increased risk of cardiovascular disease and mortality. Therefore, obtaining information regarding autonomic function in persons with SCI is pivotal and clinical examinations and laboratory evaluations to detect the presence of autonomic dysfunction and quantitate its severity are mandatory. Furthermore, previous studies demonstrated that there is an intimate relationship between the autonomic nervous system and sleep from anatomical, physiological, and neurochemical points of view. Although, even if previous epidemiological studies demonstrated that sleep problems are common in spinal cord injury (SCI), so far only limited polysomnographic (PSG) data are available. Finally, until now, circadian and state dependent autonomic regulation of blood pressure (BP), heart rate (HR) and body core temperature (BcT) were never assessed in SCI patients. Aim of the current study was to establish the association between the autonomic control of the cardiovascular function and thermoregulation, sleep parameters and increased cardiovascular risk in SCI patients.

Measurement of the $B^0$ - $\bar{B}^0$ and $B^0_s$ - $\bar{B}^0_s$ production asymmetries in pp collisions at $\sqrt{s}=7$ TeV and $\sqrt{s}=8$ TeV with the LHCb experiment

The production rate of $b$ and $\bar{b}$ hadrons in $pp$ collisions are not expected to be strictly identical, due to imbalance between quarks and anti-quarks in the initial state. This phenomenon can be naively related to the fact that the $\bar{b}$ quark produced in the hard scattering might combine with a $u$ or $d$ valence quark from the colliding protons, whereas the same cannot happen for a $b$ quark. This thesis presents the analysis performed to determine the production asymmetries of $B^0$ and $B^0_s$. The analysis relies on data samples collected by the LHCb detector at the Large Hadron Collider (LHC) during the 2011 and 2012 data takings at two different values of the centre of mass energy $\sqrt{s}=7$ TeV and at $\sqrt{s}=8$ TeV, corresponding respectively to an integrated luminosity of 1 fb$^{-1}$ and of 2 fb$^{-1}$. The production asymmetry is one of the key ingredients to perform measurements of $CP$ violation in b-hadron decays at the LHC, since $CP$ asymmetries must be disentangled from other sources. The measurements of the production asymmetries are performed in bins of $p_\mathrm{T}$ and $\eta$ of the $B$-meson. The values of the production asymmetries, integrated in the ranges $4 < p_\mathrm{T} < 30$ GeV/c and $2.5<\eta<4.5$, are determined to be: \begin{equation} A_\mathrm{P}(\B^0)= (-1.00\pm0.48\pm0.29)\%,\nonumber \end{equation} \begin{equation} A_\mathrm{P}(\B^0_s)= (\phantom{-}1.09\pm2.61\pm0.61)\%,\nonumber \end{equation} where the first uncertainty is statistical and the second is systematic. The measurement of $A_\mathrm{P}(B^0)$ is performed using the full statistics collected by LHCb so far, corresponding to an integrated luminosity of 3 fb$^{-1}$, while the measurement of $A_\mathrm{P}(B^0_s)$ is realized with the first 1 fb$^{-1}$, leaving room for improvement. No clear evidence of dependences on the values of $p_\mathrm{T}$ and $\eta$ is observed. The results presented in this thesis are the most precise measurements available up to date.

Multivariate analysis methods in the search for the Higgs boson produced in association with top pairs at the ATLAS experiment at LHC.

The Large Hadron Collider, located at the CERN laboratories in Geneva, is the largest particle accelerator in the world. One of the main research fields at LHC is the study of the Higgs boson, the latest particle discovered at the ATLAS and CMS experiments. Due to the small production cross section for the Higgs boson, only a substantial statistics can offer the chance to study this particle properties. In order to perform these searches it is desirable to avoid the contamination of the signal signature by the number and variety of the background processes produced in pp collisions at LHC. Much account assumes the study of multivariate methods which, compared to the standard cut-based analysis, can enhance the signal selection of a Higgs boson produced in association with a top quark pair through a dileptonic final state (ttH channel). The statistics collected up to 2012 is not sufficient to supply a significant number of ttH events; however, the methods applied in this thesis will provide a powerful tool for the increasing statistics that will be collected during the next LHC data taking.