Analysis of geometric defects in square locally resonant phononic crystals: A comparative study of modeling approachesa).

Phononic crystals can develop defects during manufacturing that alter the desired dynamic response and bandgap behavior. This frequency behavior change can enable successful defect inspection if the characteristic defect response is known. In this study, the behavior of a defective square unit cell comprising a freed and shortened leg is studied using a wave finite element method and an approximate continuous-lumped model to elucidate the defect induced qualitative dynamical features. These metrics are a computationally inexpensive alternative to modeling a defective unit cell within a large pristine array entirely in finite elements. The accuracy of these models is validated by comparing the result to a full finite element model. The impact of a shortened unit cell leg on the behaviors of an infinite array of defective cells and a finite array with a single defect are successfully predicted through dispersion curves and frequency response functions, respectively. These methods reveal defect-induced modes that split the local resonance bandgap of the pristine cell, as well as new anti-resonances resulting from the shortened leg. The study uses both approaches to evaluate the effect of defects in complex phononic crystal geometries and provides a comparative evaluation of the results of each model.

Study of the fatigue delamination behaviour of adhesive joints in carbon fibre reinforced epoxy composites, influence of the period of exposure to saline environment.

This work analyses the fatigue delamination and fracture stress behaviour under mode I of adhesive joints made on an epoxy matrix composite material with unidirectional carbon fibre reinforcement and a commercial epoxy-based adhesive. DCB type tests (for mode I) were used with the aim to quantify the influence of the period of exposure to a degradation process in a salt spray chamber, to which the tested samples were subjected, on their fatigue behaviour. For this purpose and after a previous static characterisation of the material in which the critical values of the energy release rate for different exposure periods were determined, the levels of the energy release rate to be applied in the fatigue tests and the exposure periods to be considered (no exposure, exposure during one week and twelve weeks) and a ratio of fatigue stress levels of R = Gmin/Gmax = 0.1 were defined. From this experimental data, the G-N fatigue initiation curves and the G-da/dN growth curves were obtained. The experimental data obtained, in the fatigue initiation phase of the delamination process, have been treated by means of a probabilistic model based on a Weibull distribution, the application of models of these characteristics has allowed a better interpretation of the experimental results obtained. The most relevant result of the work is that, in general, the fatigue limits obtained for the adhesive joint, under mode I fracture, when subjected to a degradation process in a saline environment, do not translate into a relevant loss of its resistance capacity against this fatigue delamination phenomenon, in its initiation phase. On the other hand, the crack growth rates of the material subjected to different periods of exposure to a saline environment are similar and higher than those obtained for the material without exposure.

Self-reported changes in the expanded disability status scale score in patients with multiple sclerosis after autologous stem cell transplants: real-world data from a single center.

In order to reset the immune system to baseline function, autologous hematopoietic stem cell transplantation (HSCT) has been performed in patients with multiple sclerosis (MS). After June 2015, 617 new consecutive patients with MS were autografted in our center with non-frozen peripheral blood stem cells. The autografts were performed on an out-patient basis, after conditioning with cyclophosphamide and rituximab. The aim of the study was the assessment of both safety and efficacy of the method. The study's primary co-end-points were recovery of granulocyte and platelet counts and transplant-related mortality. Secondary end-points were overall survival and clinical response (improvement or stabilization of the self-reported expanded disability status scale score). The protocol was registered in ClinicalTrials.gov identifier NCT02674217.0. We included 401 females and 216 males, with a median age of 46 years. A total of 259 patients had relapsing-remitting MS (RRMS), 228 had secondary progressive (SPMS) and 130 had primary progressive (PPMS) multiple sclerosis. All procedures were initially performed on an out-patient basis and only 32 individuals (5%) required hospitalization. One to three aphereses (median 1) were required to harvest at least 1 × 106 /kg viable CD34+ cells. The total number of viable CD34+ infused cells ranged between 1 and 37·83 × 106 /kg (median 5·68). Patients recovered more than 0·5 × 109 /l absolute granulocytes by day 8 (median, range = 2-14), and platelet values were above 20 × 109 /l by day 4 (median, range = 0-11). Eleven individuals required red blood cells and six needed platelet transfusions. To date, there have been no deaths attributable to the transplant, yielding a 30-month overall survival of 100%. Patients have been followed for 3-42 months (median = 12). The overall response rate (decrease or stabilization of the self-reported EDSS score) at 12 months was 78% for all patients (83% in RRMS, 78% in PPMS and 73% in SPMS), while the disability progression-free survival was 82% for all patients (86% in RRMS, 78·5% in SPMS and 78% in SPMS). Changes in the self-reported EDSS score in parallel with neurological improvement were observed in people with all types of MS after HSCT, employing the 'Mexican method'.

Pattern recognition for electroencephalographic signals based on continuous neural networks.

This study reports the design and implementation of a pattern recognition algorithm to classify electroencephalographic (EEG) signals based on artificial neural networks (NN) described by ordinary differential equations (ODEs). The training method for this kind of continuous NN (CNN) was developed according to the Lyapunov theory stability analysis. A parallel structure with fixed weights was proposed to perform the classification stage. The pattern recognition efficiency was validated by two methods, a generalization-regularization and a k-fold cross validation (k=5). The classifier was applied on two different databases. The first one was made up by signals collected from patients suffering of epilepsy and it is divided in five different classes. The second database was made up by 90 single EEG trials, divided in three classes. Each class corresponds to a different visual evoked potential. The pattern recognition algorithm achieved a maximum correct classification percentage of 97.2% using the information of the entire database. This value was similar to some results previously reported when this database was used for testing pattern classification. However, these results were obtained when only two classes were considered for the testing. The result reported in this study used the whole set of signals (five different classes). In comparison with similar pattern recognition methods that even considered less number of classes, the proposed CNN proved to achieve the same or even better correct classification results.

P-glycoprotein in autoimmune rheumatic diseases.

P-glycoprotein (Pgp) is a transmembrane protein of 170 kD encoded by the multidrug resistance 1 (MDR-1) gene, localized on chromosome 7. More than 50 polymorphisms of the MDR-1 gene have been described; a subset of these has been shown to play a pathophysiological role in the development of inflammatory bowel disease, femoral head osteonecrosis induced by steroids, lung cancer and renal epithelial tumors. Polymorphisms that have a protective effect on the development of conditions such as Parkinson disease have also been identified. P-glycoprotein belongs to the adenosine triphosphate binding cassette transporter superfamily and its structure comprises a chain of approximately 1280 aminoacid residues with an N-C terminal structure, arranged as 2 homologous halves, each of which has 6 transmembrane segments, with a total of 12 segments with 2 cytoplasmic nucleotide binding domains. Many cytokines like interleukin 2 and tumor necrosis factor alpha increase Pgp expression and activity. Pgp functions as an efflux pump for a variety of toxins in order to protect particular organs and tissues as the central nervous system. Pgp transports a variety of substrates including glucocorticoids while other drugs such as tacrolimus and cyclosporine A act as modulators of this protein. The most widely used method to measure Pgp activity is flow cytometry using naturally fluorescent substrates such as anthracyclines or rhodamine 123. The study of drug resistance and its association to Pgp began with the study of resistance to chemotherapy in the treatment of cancer and antiretroviral therapy for human immunodeficiency virus; however, the role of Pgp in the treatment of systemic lupus erythematosus, rheumatoid arthritis and psoriatic arthritis has been a focus of study lately and has emerged as an important mechanism by which treatment failure occurs. The present review analyzes the role of Pgp in these autoimmune diseases.

Lack of association between serum 25-hydroxyvitamin D levels and cervical human papillomavirus infection in systemic lupus erythematosus.

Our objective was to evaluate whether vitamin D deficiency is associated with cervical human papilloma virus (HPV) infection in women with SLE. This is a cross-sectional study of 67 women with SLE. A structured questionnaire was administered to ascertain the possible risk factors associated with cervical HPV infection. A gynaecological evaluation and cervical cytology screening were made. HPV detection and genotyping was made by PCR and linear array assay. Serum 25 hydroxyvitamin D levels were quantified by chemiluminescence immunoassay. Mean age and disease duration were 44.8 ± 10.6 and 42.5 ± 11.8 years, respectively. Demographic characteristics were similar in patients with and without deficiency (<20 ng/ml and ≥20 ng/ml). There were 28.4% of women with cervical HPV infection and 68.4% had high-risk HPV infections. Patients with 25 hydroxyvitamin D levels <20 ng/ml had a higher prevalence of cervical HPV infection than those with levels ≥20 ng/ml (30.7% vs. 25.8%; p = 0.72). We found no significant difference when high-risk HPV infection was evaluated (36.8% vs. 31.5%; p = 0.73). In conclusion, women with SLE have a high prevalence of vitamin D deficiency and cervical HPV infection. However, we found no association between vitamin D deficiency and cervical HPV.

Pharmacogenetic selection of volunteers increases stringency of bioequivalence studies; the case of clopidogrel.

Clinical response to clopidogrel varies widely due to under-dosing, drug interactions and intrinsic interindividual differences resulting from genetic polymorphisms. Cytochrome P450-2C19 is the principal enzyme involved in the activation of the prodrug and loss-of-function alleles have been described. Upon expiration of the pharmaceutical patent of clopidogrel, generic manufacturers have started to subject interchangeable formulations to bioequivalence studies. The purpose of the current investigation was to study the effect of selection of volunteers homozygous for the CYP2C19*1 haplotype on the bioavailability of clopidogrel. A regular 2×2 bioequivalence study between two formulations of clopidogrel was performed in volunteers selected and unselected for relevant CYP2C19 haplotypes for the Mexican population. It was found that selection of volunteers homozygous for the CYP2C19*1 haplotype, increased the stringency of bioequivalence statistics and resulted in bioinequivalence of a generic clopidogrel compound that otherwise proved equivalent when tested in an open unselected population. Augmentation of bioequivalence strictness is expected to result from pharmacogenetic selection of volunteers.

Continuous neural identifier for uncertain nonlinear systems with time delays in the input signal.

Time-delay systems have been successfully used to represent the complexity of some dynamic systems. Time-delay is often used for modeling many real systems. Among others, biological and chemical plants have been described using time-delay terms with better results than those models that have not consider them. However, getting those models represented a challenge and sometimes the results were not so satisfactory. Non-parametric modeling offered an alternative to obtain suitable and usable models. Continuous neural networks (CNN) have been considered as a real alternative to provide models over uncertain non-parametric systems. This article introduces the design of a specific class of non-parametric model for uncertain time-delay system based on CNN considering the so-called delayed learning laws analysis. The convergence analysis as well as the learning laws were produced by means of a Lyapunov-Krasovskii functional. Three examples were developed to demonstrate the effectiveness of the modeling process forced by the identifier proposed in this study. The first example was a simple nonlinear model used as benchmark example. The second example regarded the human immunodeficiency virus dynamic behavior is used to show the performance of the suggested non-parametric identifier based on CNN for no fictitious neither academic models. Finally, a third example describing the evolution of hepatitis B virus served to test the identifier presented in this study and was also useful to provide evidence of its superior performance against a non-delayed identifier based on CNN.

Genetic selection of volunteers and concomitant dose adjustment leads to comparable hydralazine/valproate exposure.

WHAT IS KNOWN AND OBJECTIVE: Hydralazine is an inhibitor of DNA methyltransferases, whereas valproate interferes with histone deacetylation. In combination, they show a marked synergism in reducing tumour growth as well as development of metastasis and inducing cell differentiation. Hydralazine is metabolized by the highly polymorphic N-acetyltransferase 2. The current pilot study was performed to analyse the pharmacokinetic parameters of a single dose of hydralazine in 24 h (one tablet with 83 mg for slow acetylators and one tablet with 182 mg for fast acetylators) and three fixed doses of valproate (one tablet of controlled liberation with 700 mg every 8 h) in healthy genetically selected volunteers. Selection was performed based on their NAT2 activity as deduced from their genotype. METHODS: An open label non-randomized single arm study was conducted in two groups of six healthy volunteers of both genders aged 20-45 years with a body mass index 22·2-26·9 which were classified as fast or slow acetylators after genotyping 3 SNPs that cover 99·9% of the NAT2 variants in the Mexican population. Blood samples were collected predose and serially post-dose in an interval of 48 h. Hydralazine and valproate concentrations were determined by ultra-high performance liquid chromatography (UPLC) coupled to tandem mass spectroscopy (MS/MS). RESULTS AND DISCUSSION: The AUC0-48 h and Cmax of hydralazine were almost identical (1410 ± 560 vs. 1446 ± 509 ng h/mL and 93·4 ± 16·7 vs. 112·5 ± 42·1 ng/mL) in both groups with NAT2 genotype-adjusted doses, whereas the multidose parameters of valproate were not significantly affected neither by the selection of the NAT2 genotype (AUC0-48 h 2064 ± 455 vs. 1896 ± 185 µg h/mL; Cmax 96·4 ± 21·1 vs. 88·8 ± 7·2 µg/mL, for the fast and slow acetylators, respectively) nor the co-administration of 83 or 182 mg of hydralazine. WHAT IS NEW AND CONCLUSION: Comparable hydralazine exposures (differences in AUC0-inf of only 7%) were observed in this study with genetic selection of volunteers and concomitant dose adjustment. However, the conclusions have yet to be confirmed with a full-powered 2 × 2 crossover study.

Evaluation of overland flow model for a hillslope using laboratory flume data.

Comprehensive modelling of overland flow requires models for both rill and interrill area overland flow. Evaluation of a physically based mathematical model for simulating overland flow generated on rill and interrill areas of hillslope was done using a data set gathered from a laboratory experimental setup. A rainfall simulator has been constructed together with a 6.50 m × 1.36 m erosion flume that can be given adjustable slopes in both longitudinal and lateral directions. The model was calibrated and validated using the experimental results from the setup of the flume having 5% lateral and 10% longitudinal slopes where rainfall intensities of 105 and 45 mm/hr were induced with the use of nozzles. Results show that for the given slope combination, the model was capable of simulating the flow coming from the rill and interrill areas for the two different rainfall intensities. It was found that significantly more of the flow occurred in the form of the rill flow. The model studied here can be used for the better prediction of overland flow and can also be used as a building block for an associated erosion and sediment transport model.

Treatment of vitiligo with a chimeric monoclonal antibody to CD20: a pilot study.

Five patients with active disseminated vitiligo were given 1g of a chimeric (murine/human) monoclonal antibody to CD20 in a single intravenous infusion and followed-up for 6 months. Three of the patients showed an overt clinical and histological improvement of the disease, one presented slight improvement and the remaining patient showed no changes. Improvement was neither associated with changes in laboratory parameters nor to a specific human leucocyte antigen D-related (HLA-DR) phenotype. We believe that these preliminary results are encouraging, and further clinical trials should be undertaken. An important aim should be the finding of a marker with a good response to this therapeutic approach.

Immunophenotypic characterization of lymphoid cell infiltrates in vitiligo.

The pathogenesis of vitiligo is still controversial. The purpose of this study was to gain insight into the nature of lymphoid cells infiltrating depigmented areas of skin in vitiligo. Immunochemical procedures were carried out in biopsies from 20 patients with active lesions to search for cells expressing CD1a, CD2, CD3, CD4, CD5, CD8, CD20, CD25, CD30, CD56, CD68 and CD79a. Results indicate that early lesions are infiltrated mainly by dendritic cells, whereas older lesions display significantly lower proportions of these cells and increased percentages of mature T cells. This finding might suggest that the autoimmune reactivity towards melanocyte antigens might be T cell-dependent and antigen-driven. It is possible that a non-immune offence of melanocytes is responsible for the exposure of intracellular antigens, while autoreactivity might be a secondary, self-perpetuating mechanism.

[Use of trabecular metal in total knee arthroplasty in severely and morbidly obese patients (BMI > 35 kg/m2)]. / Utilización del metal trabecular en artroplastía total de rodilla en pacientes obesos graves y mórbidos (IMC >35 kg/m2).

The use of trabecular metal in the tibial surface may increase prosthetic survival in the population with severe or morbid obesity (BMI > 35 kg/m2). A prospective, descriptive study was conducted of patients with a BMI > 35 kg/m2 who underwent total knee replacement with a prosthesis with trabecular metal. Minimal follow-up was two years. The statistical analysis was done with Student's t test; the Knee Society Score and the Western Ontario and McMaster Universities Osteoarthritis Index were applied preoperatively and postoperatively. The chi2 test was applied to the BMI values relating them with more or less radiolucent images. The total number of patients was 39, but three were excluded for not having the radiographic follow-up. Mean follow-up was 34 months (25-43); 35 were females, mean age was 69.4 years (57-81), mean BMI was 39.43 kg/m2 (35-55). All patients had grades 3 and 4 tricompartmental arthrosis. The KSS (R and F) and WOMAC scales, with a 95% confidence interval, showed a statistically significant improvement in the assessment of preoperative results and at the end of the followup. Only a few studies measure long-term implant survival. Most authors define survival as the absence of the need to revise prosthetic implants. The end point of survival is the removal or exchange of prosthetic components. Trabecular metal (TM) is currently used in orthopedic surgery and its clinical applications are increasing more and more with good results.

Spin-glass freezing in a Ni-vermiculite intercalation compound.

We report on the magnetic properties of a Ni(2+)-vermiculite intercalation compound from Santa Olalla, Huelva (Spain). This modified vermiculite was studied by means of DC and AC magnetic measurements. The existence of two maxima in magnetic susceptibility below 10 K was interpreted in terms of the Cole-Cole formalism as being due to spin-glass freezing in this material. The temperature, frequency and external magnetic field dependences of these anomalies located at temperatures around 2-3 K and 8-10 K in the imaginary part of the magnetic susceptibility, χ″, seem to suggest the existence of spin-relaxation phenomena between the magnetic moments of the Ni(2+) ions. A dynamic study of the relaxation processes associated with these phenomena considering the Cole-Cole formalism allows us to interpret the anomaly found at 2-3 K according to a law of activated dynamics, obtaining values for the critical exponent, ψν < 1, characteristic of a d = 2 spin-glass-like system, while the maximum observed in χ″ at 8-10 K can be described by means of a law of standard dynamics with a value of the exponent z of around 5, representative of a d = 3 spin-glass-like system.

Field-induced phase transitions of repulsive spin-1 bosons in optical lattices.

We study the phase diagram of repulsively interacting spin-1 bosons in optical lattices at unit filling, showing that an externally induced quadratic Zeeman effect may lead to a rich physics characterized by various phases and phase transitions. We find that the main properties of the system may be described by an effective field model, which provides the precise location of the phase boundaries for any dimension, in excellent agreement with our numerical calculations for one-dimensional (1D) systems. Thus, our work provides a quantitative guide for the experimental analysis of various types of field-induced quantum phase transitions in spin-1 lattice bosons. These transitions, which are precluded in spin-1/2 systems, may be realized by using an externally modified quadratic Zeeman coupling, similar to recent experiments with spinor condensates in the continuum.

Mott-insulator phases of spin-3/2 fermions in the presence of quadratic Zeeman coupling.

We study the influence of the quadratic Zeeman effect on the Mott-insulator phases of hard-core 1D spin-3/2 fermions. We show that, contrary to spinor bosons, the quadratic Zeeman coupling preserves an SU(2)⊗SU(2) symmetry, leading for large-enough quadratic Zeeman coupling to an isotropic pseudo-spin-1/2 Heisenberg antiferromagnet. Decreasing the quadratic Zeeman coupling, this phase undergoes, depending on the scattering lengths, either a Kosterlitz-Thouless transition into a gapped dimerized phase or a commensurate-incommensurate transition into a gapless spin liquid. This rich phase diagram can be observed experimentally in four-component fermions in optical lattices under similar entropy constraints to those needed for Néel order in spin-1/2 gases.

Hematoma orbitario drenado a través del seno maxilar / Orbital hematoma drained through the maxillary sinus

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Atrofia de sínfisis mandibular (hueso B-an) / Atrophy of the mandibular symphysis (B-w bone)

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Diminished expression of complement regulatory proteins (CD55 and CD59) in lymphocytes from systemic lupus erythematosus patients with lymphopenia.

CD55 and CD59 are glycophosphatidylinositol-anchored proteins with complement inhibitory properties. Lymphopenia in systemic lupus erythematosus (SLE) has been associated with autoantibodies targeting nuclear antigens. The aim of this study was to evaluate the surface density of CD55 and CD59 in T and B lymphocytes from patients with SLE and lymphopenia and its possible correlation with the presence of common SLE autoantibodies. Flow cytometric analyses were performed on CD55 and CD59 stained CD3+ and CD19+ cells from 40 SLE patients, 30 with lymphopenia and 10 without it, and 25 healthy controls. Autoantibodies were detected in the sera by enzyme linked immunosorbent assay. The mean fluorescence intensity of CD55 and CD59 in T and B cells was significantly diminished in SLE patients with lymphopenia when compared with healthy subjects. Interestingly, the opposite was found in T and B cells from non-lymphopenic SLE patients. Although there was no correlation between CD55 and CD59 surface density and the presence of any specificity of the autoantibodies tested, higher titres of anti-dsDNA, anti-SM and anti-ribosomal p antibodies were significantly associated with lymphopenia. The deficiency of CD55 and CD59 expression may play a role in the pathophysiology of lymphopenia, most likely by increasing the susceptibility of cells to complement mediated cytolysis.

La pesca ¿un deporte de riesgo? Traumatismo eléctrico / Fishing, a high-risk sport? Electric traumatism

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