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Organic chemistry is one of the most feared and failed courses due to its complex and fast-paced nature. Investigating affective metrics that relate to achievement in these courses can be worthwhile, particularly when these metrics show predictive relationships to achievement. Attitude toward chemistry has been investigated utilizing a variety of instruments. We present herein an instrument related to the well-established Attitude toward the Subject of Chemistry Inventory (ASCIv2). This new instrument was developed utilizing The Standards of Psychological and Educational Measurement, which describe five aspects of validity evidence that should be gathered when using instruments in research. Content validity was gathered through consultation with experts. Response process validity was gathered through student interviews. Internal structural validity was collected through confirmatory factor analysis. Relations to other variables were investigated through correlation analysis and structural equation modeling. Consequential validity was studied through measurement invariance testing before comparing scores for subgroups (high- and low-achieving students). Additionally, reliability evidence was tested with Omega coefficients for each of the factors. We showed that all tests and analyses were done with high rigor, and that this new instrument, ASCI-UE, measuring utility and e motional satisfaction, can provide interesting results and implications for research and practice.

Attitudes towards learning chemistry have been little studied in secondary school students, especially regarding dimensions related to problem solving, the molecular atomic perspective of chemistry, and real-world connection of chemistry. In the present study, we first aimed to design and assess the psychometric properties of the attitude to learning Chemistry instrument (ALChI). A second aim of the study was to assess sex differences and the relation between achievement and attitudes. Participants were 503 secondary school students, from a central southern region of Chile, who answered a 23-item version of the ALChI. The results of the exploratory factor analysis (EFA) revealed that an 18-item scale was most appropriate grouped into four factors: real world connection (RWC), perceived difficulty in problem-solving (PDPS), confidence in problem solving (CPS), and atomic molecular perspective of chemistry (AMPCh). Confirmatory factor analysis (CFA) confirmed the four-factor structure of the model, with optimal fit indexes. Sex factorial invariance was also obtained for configural, metric, and scalar models, demonstrating that ALChI was invariant for sex. Reliability analysis showed moderate to good indices, which suggests good internal consistency of ALChI. On a descriptive level, the highest mean was for the CPS subscale, which entails that students showed a favourable disposition towards their ability to succeed in solving chemistry problems. A structural equation multiple indicators multiple causes (MIMIC) model was conducted to compare factor latent means for sex and assess the relationship between achievement and attitude latent variables. These analyses revealed that achievement was positively associated with all four latent factors. However, no difference by sex was observed across all four factor means. These findings are partially in line with the results from previous studies in more developed countries where attitudes towards chemistry have been consistently linked to academic performance and male students tend to have more positive attitudes than their female counterpart. Our findings are of relevance for researchers, school teachers, and secondary school students since attitudes towards learning chemistry play an important role in choosing a future career path.

En esta investigación se indagó acerca de las actitudes hacia la química de 444 estudiantes de secundaria chilenos, empleando un método mixto de diseño secuencial explicativo. Los resultados descriptivos revelaron actitudes relativamente bajas en las dos dimensiones analizadas, cognitiva y afectiva, aunque levemente superiores en la última. Los resultados inferenciales mostraron que el nivel escolar y el rendimiento académico afectan a las actitudes de manera negativa y positiva, respectivamente. Los resultados de tres grupos focales permitieron profundizar en las explicaciones sobre los hallazgos cuantitativos y revelaron que otros factores, como los cálculos matemáticos, el lenguaje de la química y la metodología del profesor, también son relevantes en el desarrollo de las actitudes hacia la química. Se discuten estos hallazgos y sus implicaciones para la enseñanza de la química en Chile y Latinoamérica. This research investigated the attitudes towards chemistry of 444 Chilean secondary school students, using a mixed method of explanatory sequential design. The descriptive results revealed relatively low attitudes in the two dimensions analyzed, cognitive and affective, although slightly higher in the last one. The inferential results showed that year group and academic performance affect attitudes negatively and positively, respectively. The results of three focus groups allowed to deepen the explanations on the quantitative findings and revealed that other factors such as mathematical calculations, the language of chemistry and the teacher's methodology are also relevant in the development of attitudes towards chemistry. These findings and their implications for the teaching of chemistry in Chile and Latin America are discussed.

espanolObjetivo Traduccion, transculturizacion y validez del cuestionario autoadministrado para funcionalidad (Systemic Sclerosis Questionnaire [SySQ]) en esclerosis sistemica al idioma espanol y su relacion con la enfermedad y la calidad de vida. Pacientes y metodos Estudio observacional analitico. Validacion realizada por panel de expertos, en apariencia y contenido. La metodologia incluyo: a) adaptacion al espanol del constructo por traduccion, retrotraduccion, y transculturizacion; b) consistencia interna para todas y cada una de las categorias del SySQ (alfa de Cronbach), y c) la reproducibilidad se evaluo tomando en cuenta todas las ocasiones en que se realizo la prueba con kappa de Cohen. Adicionalmente calculamos el coeficiente de correlacion de Spearman con: 1) escala de severidad de Medsger; 2) Health Assessment Questionnaire, y 3) prueba SF-36. Resultados Se incluyeron 70 pacientes con esclerosis sistemica, edad 17-78 (51 ± 12) anos, 65 (93%) mujeres, subtipo difuso/limitado 64/36%, evolucion de la enfermedad 0,5-40 anos. Observamos consistencia interna optima de la version final del SySQ (alfa de Cronbach 0,961) y buena reproducibilidad intraobservador entre pruebas con intervalo de 2 semanas (kappa de Cohen 0,618) y optima interobservador el mismo dia (kappa de Cohen 0,911). Moderada correlacion entre los cuestionarios de funcionalidad SySQ y de discapacidad de Health Assessment Questionnaire (r = 0,573; p Conclusiones Esta version en espanol del cuestionario autoadministrado SySQ es un instrumento valido para evaluar el estado funcional de pacientes con esclerosis sistemica. La menor funcionalidad esta relacionada con una mayor afeccion a tendon y vascular periferico y con una menor calidad de vida. EnglishObjective Translation, transculturation and validity of the self-administered questionnaire for functionality (Systemic Sclerosis Questionnaires [SySQ]) for use in Spanish patients with systemic sclerosis and its relationship to the severity of the disease and to quality of life. Patients and methods We conducted an observational analytical study to perform a cross-cultural validation of the self-administered questionnaire on functionality in scleroderma. The validity of the form and content was evaluated by an expert panel. The method included: a) adaptation into Spanish of the construct for translation and back translation, and transculturation; b) internal consistency with the SySQ (Cronbach's alpha), and c) reproducibility was assessed taking into account all occasions in which the test was performed with Cohen's kappa. Additionally, we calculated the Spearman correlation coefficient with the Medsger severity scale, Health Assessment Questionnaire score and SF-36 score. Results We included 70 patients with systemic sclerosis: age 17-78 (51 ± 12) years, 65 (93%) were women, diffuse/limited subtype 64/36%, disease duration of 0.5-40 years. Optimal internal consistency for all categories of the final version of SySQ (Cronbach's α of 0.961) and intraobserver reliability in 2 tests over a 2-week interval (Cohen's kappa coefficient 0.618) and optimal interobserver reliability in 2 tests on the same day (Cohen's kappa coefficient 0.911). Moderate correlation between functionality by SySQ and by Health Assessment Questionnaire (r = 0.573, P Conclusions SySQ in this validated Spanish version is a suitable instrument to measure functional status in patients with systemic sclerosis. Reduced functionality is related to greater tendon and peripheral vascular involvement and to a poorer quality of life.

BackgroundModern imaging plays a central role in the care of obese patients, and there is an integral focus on its use and accessibility in individuals who have alterations of various in various organs. The objective in this study was to perform an echographic analysis of musculoskeletal system disorders, endothelial dysfunction and the left ventricle (LV) in obese rats.MethodsSprague Dawley rats (250 ± 5 g) were obtained and divided into two groups: the control (C) group was fed with a standard diet, and the obese (Ob) group was fed hyper caloric diet with a high fructose-fat content for 4 months. Body weight, cholesterol, triglycerides, glucose, inflammatory cytokines and adhesion molecules (ICAM-1, VCAM-1) were measured. Additionally, two-dimensional echocardiography, abdominal ultrasound and musculoskeletal system studies were performed in the lower extremities.ResultsThe body weight in the Ob group was increased compared to that in the control group, (p p p ConclusionObese rats exhibit endothelial dysfunction and musculoskeletal changes, also, fatty liver and articular cysts in the posterior region of the distal lower- extremity joints.

Background: Modern imaging plays a central role in the care of obese patients, with an integral focus on its use and accessibility in individuals into this condition with alterations of various organs. Objective. To perform an echographical analysis of musculoskeletal system disorders, endothelial dysfunction and the left ventricle in obese rats. Methods. Sprague Dawley rats (250±5 g) were used and divided in two groups: control group (C) fed with a standard diet, and the obese group (Ob) fed with a hyper caloric diet of high fructose-fat for 4 months. Body weight, cholesterol, triglycerides, glucose, inflammatory cytokines and adhesion molecules (ICAM-1, VCAM-1) were measured. Additionally, two-dimensional echocardiography, abdominal ultrasound and musculoskeletal system studies were performed in the lower extremities.Results. Body weight in the Ob group was increased compared to the control group, (p Conclusion. Endothelial dysfunction and changes at the level of the musculoskeletal system with the presence of joint cysts in the posterior region of the distal joint of the lower extremities and fat liver were observed in obese rodents.

Distinction between infection and flare in patients with systemic lupus erythematosus (SLE) is a challenge in clinical practice. Objective To analyze the utility of neutrophil-to-lymphocyte ratio (NLR) plus C-reactive protein (CRP) to differentiate between infection and active disease in patients with SLE. Methods A cross-sectional study of a cohort of patients with SLE was carried out. Blood samples from four groups (patients without infection or active disease, patients with infection, patients with active disease, and patients with both infection and active disease) before therapeutic interventions were analyzed. We excluded patients with current malignancy, pregnancy, ischemic heart disease or use of antimicrobials during previous 7 days. Hematological cell count, CRP and cultures were obtained. We constructed receiver operating characteristic curves; sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Results Forty patients were included. NLR cut-off ≥6.3 had sensitivity 70%, specificity 85%, PPV 83% and NPV 74% to detect patients with non-viral infections. A CRP cut-off ≥7.5 mg/L had sensitivity 90%, specificity 75%, PPV 78% and NPV 88% to detect infections regardless of SLE activity. Combination of CRP plus NLR improves the specificity to 90% and PPV to 88%. Excluding the group with both infection and active disease, CRP plus NLR expands specificity to 95% and NPV to 90%. Conclusion In our experience, levels of CRP, particularly CRP plus NLR, were useful in differentiating patients with SLE from those with suspected non-viral infection regardless of the activity of the disease.

Research into attitudes towards chemistry in Latin America and indeed towards science in general is very limited. The present study aimed to adapt and validate a shortened version of Bauer's Attitude toward the Subject of Chemistry Inventory version 2 (ASCIv2) for use in a Latin American context. It also explored attitudes towards chemistry of Chilean secondary school students, and assessed the effect of school type, year group, gender, and chemistry achievement on both cognitive and affective dimensions. The participants were 523 secondary school students from public, private subsidised, and private schools in Chile. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were first carried out to validate ASCIv2. The results of CFA showed that ASCIv2 retained the two-factor structure and showed optimal model fit, but three items had to be removed from the original instrument. The research also showed that attitudes towards science were neither positive nor negative, a reality similar to that of other countries. The results of multivariate and univariate analyses of variance showed significant effects of year group and chemistry achievement on attitudes towards chemistry. No effects of school type, gender or interactions between factors were found. Follow-up analyses revealed that as students advance through school their attitudes decline, but that the higher their chemistry marks, the more positive their attitudes become. These findings are partially in line with previous data from other countries and are a starting point for more research into attitudes towards chemistry in Latin America.

We study the flavor-changing decay $h\to ����$ with $��=��^-+��^+$ and $��=��^-+��^+$ of a Higgs boson at future hadron colliders, namely: a) High Luminosity Large Hadron Collider, b) High Energy Large Hadron Collider and c) Future hadron-hadron Circular Collider. The theoretical framework adopted is the Two-Higgs-Doublet Model type III. The free model parameters involved in the calculation are constrained through Higgs boson data, Lepton Flavor Violating processes and the muon anomalous magnetic dipole moment; later they are used to analyze the branching ratio of the decay $h\to����$ and to evaluate the $gg\to h$ production cross section. We find that at the Large Hadron Collider is not possible to claim for evidence of the decay $h\to����$ achieving a signal significance about of $1.46��$ by considering its final integrated luminosity, 300 fb$^{-1}$. More promising results arise at the High Luminosity Large Hadron Collider in which a prediction of 4.6$��$ when an integrated luminosity of 3 ab$^{-1}$ and $\tan��=8$ are achieved. Meanwhile, at the High Energy Large Hadron Collider (Future hadron-hadron Circular Collider) a potential discovery could be claimed with a signal significance around $5.04��$ ($5.43��$) for an integrated luminosity of 3 ab$^{-1}$ and $\tan��=8$ (5 ab$^{-1}$ and $\tan��=4$)., Accepted version to be published in JHEP, typos corrected, added citations

International audience; In this study, we address the question of the equivalent role of the pressure and temperature on the mechanical properties of highly filled elastomers. It is well known that in polymer matrixes, the equivalence of temperature and pressure results from free volume variations. Our measurements performed on phenylated polydimethylsiloxane (PDMS) chains filled with silica particles show that a temperature-pressure superpo-sition property is still observed in both linear and nonlinear regimes in these systems. However, the temperature-pressure equivalence involves coefficients that are two orders of magnitude larger than those in non-reinforced matrixes. We suggest that the mechanical response of the filled elastomers is controlled by the shape of the rigid network made by fillers that are connected by rigid polymer bridges. In this frame, we provide quantitative evidence that the macroscopic behavior of reinforced elastomers is controlled by the variation in the degree of the confinement of polymer chains between particle surfaces.

International audience; It has been known for several decades that rubbers exhibit a hydrostatic pressure-temperature superposition, interpreted by the free-volume theory. Moreover, our experimental results, on a filled rubber, demonstrate a hydrostatic pressure-temperature superposition which is two orders of magnitude larger than the one observed in pure rubbers. A new physico-mechanical model is proposed to account for the hydrostatic pressure effect responsible for a local glass transition temperature shift. It is suggested that it comes from the change of distances between aggregates. The predicted shift, given by the model, is found to be consistent with experimental data.

We study the decay t → cγ with flavor-changing neutral interactions in scalar sector of the type III Two Higgs Doublet Model (THDM-III) with mixing between neutral scalar fields as a result of considering the most general scalar potential. The branching ratio of the decay Br (t → cγ) is calculated as function of the mixing parameters and masses of the neutral scalar fields. We obtain a Br (t → cγ) of the order of 10−8 for the considered regions of the mixing parameters. Finally, one upper bound for the possible events is estimated to be n=18 by assuming an expected luminosity of the order of 300 fb−1.

Background: Hepatic encephalopathy (HE) in patients with chronic liver disease (CLD) is one of the main causes of reentry to the emergency department. Oxidative stress (OxS) regulated by ammonia leads to cerebral edema and astrocytes senescence in animal models, but seems to be different in humans. Objective: To analyze if OxS and ammonia in plasma are related to each other in the different grades of HE-CLD and to compare them with healthy volunteers (HV). Methods: In a cross-sectional study, we included 60 subjects in 2 groups: (a) 30 HV and (b) 30 HE patients. Plasma levels of oxidation lipids/proteins, ammonia, and West-Haven score were evaluated. Student t test, Spearman’s correlation, and ANOVA with Dunn’s post hoc test were performed. Results: Ammonia in HV and HE patients was 39–49 vs. 95–345 μmol/L, respectively (p < 0.0001). Malondialdehyde (MDA) in HV was 6.58 ± 3.11 compared to 16.69 ± 6.19 μmol/L in HE (p < 0.0001). Protein oxidation by osazone (carbonyls), formazan, and dityrosines was higher in HE than in HV (p < 0.0001). Ammonia level was directly associated to HE severity, but without correlation with lipid MDA or protein OxS formazan, carbonyls, and dityrosines. Lipid peroxidation showed higher levels at degree 2 and protein oxidation at degree 3 of HE. Conclusions: We confirm that OxS accompanies hyperammonemia in HE; however they contribute in different proportions to their natural progression. Early reduction of OxS in HE could contribute to minimize the neurotoxicity into CLD.

Background In microsurgical reconstruction, vascular obstruction occurs in approximately 20% of patients. Close monitoring is central to their care. Clinical/Doppler detection of vascular obstruction could be enhanced by thermography. Methods A diagnostic test design included consecutive cases of hospitalized patients, ≥18 years old, who underwent surgery with free flaps. Two researchers separately evaluated patients with clinical/Doppler methods and thermographic camera hourly for 24 hours, every 2 hours for the next 24 hours, and then every 3 hours until discharge. The gold standard was visualization of thrombus or vascular obstruction during surgical reintervention. Sensitivity, specificity, positive/negative predictive value (PPV/NPV), and a delta temperature receiver operating characteristic (ROC) curve were calculated. Results A total of 2,364 tests were performed with a thermographic camera in 40 patients (31 females, 9 males) aged 50.12 ± 9.7 years. There were 28 deep inferior epigastric perforator, 5 anterolateral thigh, 3 radial, 2 scapular, 1 fibular, and 1 anteromedial thigh flaps included. Six (15%) had postoperative vascular obstruction (5 venous and 1 arterial). One flap developed partial necrosis and one total necrosis (overall survival 97.5%). ROC curve (area 0.97) showed the best results at ≥ 1.8°C of difference to the surrounding skin. Considering two consecutive positive evaluations, the sensitivity was 93%, specificity 96%, PPV 57%, and NPV 99%. The thermal imaging camera allows to identify the obstruction between 2 and 12 hours before the clinical method. Conclusion Utilizing a thermographic camera can reduce detection time of vascular obstruction by several hours in microvascular free flaps that include the cutaneous island. This method proves useful for early diagnosis of postoperative vascular obstruction.

The automatic characterization and classification of plant species is an important task for plant taxonomists. On this work, we propose the use of well-known pre-trained Deep Convolutional Neural Networks (DCNN) for the characterization of plants based on their leaf midrib. The samples studied are microscope images of leaf midrib cross-sections taken from different specimens under varying conditions. Results with traditional handcrafted image descriptors demonstrate the difficulty to effectively characterize these samples. Our proposal is to use DCNN as a feature extractor through Global Average Pooling (GAP) over the raw output of its last convolutional layers without the application of summarizing functions such as ReLU and local poolings. Results indicate considerably performance improvements over previous approaches under different scenarios, varying the image color-space (gray-level or RGB) and the classifier (KNN or LDA). The highest result is achieved by the deeper network analyzed, ResNet (101 layers deep), using the LDA classifier, with \(99.20\%\) of accuracy rate. However, shallower networks such as AlexNet also provide good classification results (\(97.36\%\)), which is still a significant improvement over the best previous result (\(83.67\%\) of combined fractal descriptors).

We study the observability for the flavor-changing decay of a top quark $t\to ch$ at the LHC and future hadron colliders, namely, High-Luminosity LHC (HL-LHC), High-Energy LHC (HE-LHC) and Future Circular hadron-hadron Collider (FCC-hh). Two scenarios in which the Higgs boson could decay: into a quark bottom pair $(\textit{bb-channel})$ and two photons $(\textit{$\gamma\gamma$-channel})$ are analyzed. A Monte Carlo analysis of the signal and the Standard Model (SM) background is computed. Center-of-mass energies of $\sqrt{s}=14,\;27\; $\text{and}$\; 100$ TeV and integrated luminosities from $0.3$ to $30$ ab$^{-1}$ are explored. The theoretical framework adopted in this work is the Type-III Two-Higgs Doublet Model (THDM-III) for which, constraints on the parameter space from the Higgs boson coupling modifiers $\kappa_i$ are presented and used in order to evaluate the branching ratio of the $t\to ch$ decay and the ($pp\to t\bar{t},\,t\to ch$) production cross section. We find that with the integrated luminosity achieved at the LHC, the $t\to ch$ decay is out of the reach of detection. More promising results emerge for the HL-LHC, HE-LHC and FCC-hh in which potential discoveries could be claimed., Comment: Version to be published in JHEP

We study Dark Matter (DM) abundance in the framework of the extension of the Standard Model (SM) with an additional $U(1)_X$ gauge symmetry. One complex singlet is included to break the $U(1)_X$ gauge symmetry, meanwhile one of the doublets is considered inert to introduce a DM candidate. The stability of the DM candidate is analyzed with a continuous $U(1)_X$ gauge symmetry as well as discrete $Z_2$ symmetry. We find allowed regions for the free model parameters which are in agreement with the most up-to-date experimental results reported by CMS and ATLAS collaborations, the upper limit on WIMP-nucleon cross section imposed by XENON1T collaboration and the upper limit on the production cross-section of a $Z^{\prime}$ gauge boson times the branching ratio of the $Z^{\prime}$ boson decaying into $\ell^-\ell^+$. We also obtain allowed regions for the DM candidate mass from the relic density reported by the PLANCK collaboration including light, intermediate and heavy masses; depending mainly on two parameters of the scalar potential, $\lambda_{2x}$ and $\lambda_{345}=\lambda_3+\lambda_4+2\lambda_5$. We find that trough $pp\rightarrow \chi\chi \gamma$ production, it may only be possible for a future hadron-hadron Circular Collider (FCC-hh) to be able to detect a DM candidate within the range of masses 10-60 GeV., Comment: Accepted version to be published in EPJC, typos corrected, cites added

The addition of rigid fillers to an elastomeric matrix enhances its mechanical properties. This reinforcement effect is primarily due to a filler network structure in which polymer regions between aggregates play the principal role. In this study, a continuum constitutive equation is formulated for polymer behavior under strong confinement conditions. This behavior can be accounted for by a local glass transition temperature that combines the effects of physical interaction and stress softening in a unique viscoelastic formulation. The model reproduces, at a microscopic scale, the processes governing the Payne effect, including the temperature dependence of the viscoelastic behavior of the filled elastomer reinforcement.

We compute the contributions to rare top decays $t\ensuremath{\rightarrow}cZ$ and $t\ensuremath{\rightarrow}c{h}_{1}$ from the scalar sector in the two Higgs doublet model type III with $CP$ violation, where ${h}_{1}$ is the Standard Model Higgs boson. The branching ratios for $\mathrm{BR}(t\ensuremath{\rightarrow}cZ)$ and $\mathrm{BR}(t\ensuremath{\rightarrow}c{h}_{1})$ are obtained as a function of the model parameters. In particular, the $\mathrm{BR}(t\ensuremath{\rightarrow}cZ)$ can increase its value up to ${10}^{\ensuremath{-}3}$ for $\mathrm{tan}\ensuremath{\beta}=1$ and masses for the additional Higgs bosons of ${m}_{{h}_{2},{h}_{3},{H}^{\ifmmode\pm\else\textpm\fi{}}}\ensuremath{\sim}0.5\text{ }\text{ }\mathrm{TeV}$. Meanwhile $\mathrm{BR}(t\ensuremath{\rightarrow}c{h}_{1})$ can reach values of the order of $\ensuremath{\sim}{10}^{\ensuremath{-}2}$. We constrain the model parameters (mixing angles of the neutral scalar fields in the $CP$ violation context and $\mathrm{tan}\ensuremath{\beta}$) using the reported values of the signal strengths ${R}_{XX}$ and $b\ensuremath{\rightarrow}s\ensuremath{\gamma}$ process.

A new method based on complex networks is proposed for color-texture analysis. The proposal consists on modeling the image as a multilayer complex network where each color channel is a layer, and each pixel (in each color channel) is represented as a network vertex. The network dynamic evolution is accessed using a set of modeling parameters (radii and thresholds), and new characterization techniques are introduced to capt information regarding within and between color channel spatial interaction. An automatic and adaptive approach for threshold selection is also proposed. We conduct classification experiments on 5 well-known datasets: Vistex, Usptex, Outex13, CURet and MBT. Results among various literature methods are compared, including deep convolutional neural networks with pre-trained architectures. The proposed method presented the highest overall performance over the 5 datasets, with 97.7 of mean accuracy against 97.0 achieved by the ResNet convolutional neural network with 50 layers., 20 pages, 7 figures and 4 tables

Objectives The aim of the study was to study the factors associated with immunological recovery in HIV-infected patients with suppressed viral load. Methods Nadir and current CD4 cell counts were recorded in 821 patients, as well as many demographic, epidemiological, lifestyle, clinical, therapeutic, genetic, laboratory, liver fibrosis and viral hepatitis parameters. Results The median age of the patients was 44.4 years [interquartile range (IQR) 40.3–48.0 years], the median time since HIV diagnosis was 15.3 years (IQR 10.5–18.9 years), the median time of suppressed viral load was 7.0 years (IQR 4.0–10.0 years) and the median time on the current antiretroviral regimen was 2.8 years (IQR 1.4–4.7 years). The median nadir and current CD4 counts were 193.0 (IQR 84.0–301.0) and 522.0 (IQR 361.0–760) cells/μL, respectively, separated by a median period of 10.2 years (IQR 5.9–12.9 years). The median CD4 count gain during follow-up was 317.0 (IQR 173.0–508.0) cells/μL. Many variables were associated with CD4 cell gains in univariate analyses, including age, gender, epidemiology, prior clinical conditions, fibrosis stage, transient elastometry, aspartate aminotransferase (AST), nadir CD4 count and hepatitis B and C virus infections and genotypes, as well as the durations of follow-up since nadir CD4 count, overall antiretroviral treatment, current antiretroviral regimen, protease inhibitor therapy and suppression of viral load. Multivariate analysis revealed that longer duration of HIV suppression (P < 0.0001), more advanced clinical Centers for Disease Control and Prevention (CDC) stages (P < 0.0001), younger age (P = 0.0003), hepatitis C virus genotypes 1 and 4 (P = 0.003), sexual acquisition of HIV (P = 0.004), and lower transient elastometry values (P = 0.03) were independent predictors of CD4 cell gains. Overall, the model accounted for 14.2% of the variability in CD4 count. Conclusions In addition to the duration of HIV suppression, HIV-related diseases, HIV epidemiology, age, hepatitis C virus genotypes, and liver fibrosis were independently associated with long-term immunological recovery.

In the framework of a left-right model containing mirror fermions (LRMM) with gauge group S U ( 3 ) C ⊗ S U ( 2 ) L ⊗ S U ( 2 ) R ⊗ U ( 1 ) Y ′ , we estimate the neutrino masses, which are found to be consistent with their experimental bounds and hierarchy. We also estimate the decay rates of heavy Majorana neutrinos in the channels N → W ± l ∓ , N → Z ν l and N → H ν l , which are roughly equal for large values of the heavy neutrino mass. Starting from the most general Majorana neutrino mass matrix, the smallness of active neutrino masses turns out from the interplay of the hierarchy of the involved scales and the double application of seesaw mechanism. An appropriate ansatz on the structure of the neutrino mass matrix imposing a symmetric mixing of electron neutrino with muon and tau neutrinos leads to tribimaximal mixing matrix for light neutrinos.

International audience; In this paper we focus on the role of dynamical heterogeneities on the non-linear response of polymers in the glass transition domain. We start from a simple coarse-grained model that assumes a random distribution of the initial local relaxation times and that quantitatively describes the linear viscoelasticity of a polymer in the glass transition regime. We extend this model to non-linear mechanics assuming a local Eyring stress dependence of the relaxation times. Implementing the model in a finite element mechanics code, we derive the mechanical properties and the local mechanical fields at the beginning of the non-linear regime. The model predicts a narrowing of distribution of relaxation times and the storage of a part of the mechanical energy --internal stress-- transferred to the material during stretching in this temperature range. We show that the stress field is not spatially correlated under and after loading and follows a Gaussian distribution. In addition the strain field exhibits shear bands, but the strain distribution is narrow. Hence, most of the mechanical quantities can be calculated analytically, in a very good approximation, with the simple assumption that the strain rate is constant.

Every year, efficient maize production is very important to the economy of many countries. Since nutritional deficiencies in maize plants are directly reflected in their grains productivity, early detection is needed to maximize the chances of proper recovery of these plants. Traditional texture methods recently showed interesting results in the identification of nutritional deficiencies. On the other hand, deep learning techniques are increasingly outperforming hand-crafted features on many tasks. In this paper, we propose a simple transfer learning approach from pre-trained cnn models and compare their results with those from traditional texture methods in the task of nitrogen deficiency identification. We perform experiments in a real-world dataset that contains digitalized images of maize leaves at different growth stages and with different levels of nitrogen fertilization. The results show that deep learning based descriptors achieve better success rates than traditional texture methods.

Background Autonomic dysfunction, smooth muscle fibrosis and vascular damage lead to small intestinal bacterial overgrowth (SIBO) in Systemic Sclerosis (SSc). SIBO is characterized by diarrhea, abdominal pain, bloating, malabsorption and malnutrition. Objectives To evaluate by NIH PROMIS® gastrointestinal symptoms scales and SIBO by hydrogen breath test (HBT) in patients with SSc. Methods We include 68 patients with SSc (ACR-EULAR 2015) who signed informed consent. NIH PROMIS®questionarie was applied to evaluated gastrointestinal symptoms and classified in not symptomatic, least, mildy, moderately and most symptomatic. Glucose HBT was applied after 14 hours fast, oral hygiene and 30 days free of antibiotics. Patients who has a negative HBT with symptoms associated to glucose ingestion we repeat test with lactulose. Results We applied questionnaire to 58 SSc patients, age 52 (26–75)years, 65 (96%) female and 3 (4%) males, disease duration 13 (1–40) years, limited SSc 41 (59%) and diffuse 27 (41%), body mass index 24 (12–39). They are using prednisone (28%), micofenolate (14%), methotrexate (19%), azatioprin (5%), amlodipine or nifedipine (33%). Patients had continuous and very high increase of parts per millon (ppm) of exhaled Hydrogen: min0: 13 ppm (5–21), min15:17 ppm (5–43), min30:17 (3–49), min45:18ppm (7–103), min 60:22ppm (8–145), min90:18ppm (2–250), min120:25ppm (3–212), min150:71ppm (3–235). Normal values: Frequency of gastrointestinal symptoms were flatulence (87.5vs81.2%), nausea/vomiting (72.7vs37.6%), constipation (65.6vs40%), diarrhea (45.2vs33.4%), abdominal pain %) and incontinence (39.4vs31.3%) respectively between SCB (+) positive and negative. Hyperproduction of hydrogen in breath had a direct correlation to severity of their symptoms (p≤0.05). The severity of diarrhea was in close relation to the severity of its rectal incontinence (r=0.73,p=0.001), and greater abdominal pain with flatulence (r=72, p=0.001). Conclusions Gastrointestinal symptoms are common in SSc regardless of whether they have SIBO. However, a higher Row Score SGI or moderate severe status (NIH PROMIS) correlates with high H scores from the 30th minute, therefore, the questionnaire is useful within the SSc assessment. Disclosure of Interest None declared