Influence of pressure and temperature on key physicochemical properties of corn stover-derived biochar

This study focuses on analyzing the effect of both the peak temperature and pressure on the properties of biochar produced through slow pyrolysis of corn stover, which is a common agricultural waste that currently has little or no value. The pyrolysis experiments were carried out in a fixed-bed reactor at different peak temperatures (400, 525 and 650 °C) and absolute pressures (0.1, 0.85 and 1.6 MPa). The inert mass flow rate (at NTP conditions) was adjusted in each test to keep the gas residence time constant within the reactor. The as-received corn stover was pyrolyzed into a biochar without any physical pre-treatment as a way to reduce the operating costs. The properties of biochars showed that high peak temperature led to high fixed-carbon contents, high aromaticity and low molar H:C and O:C ratios; whereas a high pressure only resulted in a further decrease in the O:C ratio and a further increase in the fixed-carbon content. Increasing the operating pressure also resulted in a higher production of pyrolysis gas at the expense of water formation

Tratamiento de última generación químico-mecánico de la caries dental

El tratamiento de última generación químico-mecánico de la caries dental es preconizada por la OMS, como alternativa al tratamiento rehabilitador para países como el nuestro, así como para poblaciones marginales y/o rurales, donde hay dificultades para practicar una odontología convencional, por falta de equipos y/o de energía eléctrica. Esta técnica de restauración TRA, debe ser insertada en todo Programa Preventivo Promocional de Salud Oral. En nuestra Facultad, en que se forman recursos humanos conocedores de su realidad epidemiológica de salud oral nacional, se les debe de preparar en la práctica de Clínica Comunitaria en el ámbito de la periferia de la Universidad, como prácticas preprofesionales, contribuyendo así a la formación de profesionales capaces de enfrentar las adversidades, con armas científicas contundentes, logrando el sueño de nuestra profesión que es el de disminuir los altos índices de prevalencia de las caries dental, pudiendo alcanzar metas de la OMS para el año 2010.El tratamiento de última generación químico-mecánico de la caries dental es preconizada por la OMS, como alternativa al tratamiento rehabilitador para países como el nuestro, así como para poblaciones marginales y/o rurales, donde hay dificultades para practicar una odontología convencional, por falta de equipos y/o de energía eléctrica. Esta técnica de restauración TRA, debe ser insertada en todo Programa Preventivo Promocional de Salud Oral. En nuestra Facultad, en que se forman recursos humanos conocedores de su realidad epidemiológica de salud oral nacional, se les debe de preparar en la práctica de Clínica Comunitaria en el ámbito de la periferia de la Universidad, como prácticas preprofesionales, contribuyendo así a la formación de profesionales capaces de enfrentar las adversidades, con armas científicas contundentes, logrando el sueño de nuestra profesión que es el de disminuir los altos índices de prevalencia de las caries dental, pudiendo alcanzar metas de la OMS para el año 2010

La dependencia y los cuidadores informales

En el trabajo que se presenta a continuación se realiza un análisis de la realidad actual, tanto de la situación de dependencia en personas mayores como la de sus familias cuidadoras. El objetivo es poner de relieve la importancia que éstas tienen en el cuidado y, por lo tanto, la necesidad de ser formadas, apoyadas y ayudadas en esta tarea; de tal manera que se garantice su calidad de vida y bienestar. Y, por consiguiente, esto se refleje de manera positiva en la tarea de cuidado que realicen. Para ello, se presenta el tema de la dependencia analizada desde un punto de vista biológico y social, y posteriormente se analiza la evolución del concepto a lo largo del tiempo hasta la concepción última que aporta la Ley de la Autonomía personal y Atención a la Dependencia, donde el cuidador familiar adquiere una relevancia muy importante a nivel teórico pero, sin embargo, no se plasma a nivel prácticos en políticas y servicios sociales, que se vieron condicionados por la crisis económica que inicia alrededor de 2007. A continuación se describe el perfil sociodemográfico del cuidador hoy en día, así como el impacto y las consecuencias que implica en la estructura familiar el asumir el cuidado de una persona dependiente. Además de señalar las medidas de atención y ayuda existentes hoy en día para estos cuidadores. Se concluye con una propuesta educativa preventiva dirigida a futuros cuidadores informales, con el fin de orientar al profesional sobre los distintos aspectos que podría trabajar y desarrollar en la unidad familiar

Single waveguide silicon-organic hybrid modulator

We present a novel silicon-organic hybrid modulator based on an integrated dual-mode interferometer. The modulator offers a compact, simplified design and enhanced robustness to on-chip fluctuations of temperature compared to conventional Mach-Zehnder based systems. A prototype modulator showing a voltage dependent transmission spectrum is obtained by cladding a dual-mode waveguide in a 250 nm silicon-on-insulator technology with a customized organic electro-optic layer. Estimated phase shifts and corresponding figures of merit are discussed in this contribution. The used organic layer is based on the guest-host approach with customized donor-acceptor chromophore embedded and poled in a poly(methylmethacrylate) matrix. The presented prototype is to the best of the authors'' knowledge the first integrated single waveguide silicon-organic hybrid modulator

Push-pull thiophene chromophores for electro-optic applications: from 1D linear to beta-branched structures

We report the synthesis and characterization of a novel series of push-pull chromophores bearing 1D linear and beta-branched thiophenes as pi-conjugated spacers between a 2, 2, 4, 7-tetramethyl-1, 2, 3, 4-tetrahydroquinoline electron donor unit and dicyano- and tricyanovinylene electron acceptor groups. The effect of the introduction of beta-thiophenes on the linear and nonlinear (NLO) optical properties as well as electrochemical and thermal data is studied in detail by performing a comparative study between the branched and 1D linear systems. In addition, a parallel DFT computational study is used to evaluate structure-property relationships. The non-linear optical behavior of the molecules both in solution and in solid state as electro-optic (EO) films using a guest-host approach shows very promising performance for electro-optic applications with high molecular first hyperpolarizabilities (mu beta) of 4840 x 10(-48) esu and electro-optic coefficients r(33) reaching 650 pm V-1. One highlight is that the electro-optic films of the beta-branched chromophores are superior in terms of thermal stability in device operation as measured by a transmissive modified reflective Teng-Man method. This work provides guidelines for the design of improved electro-optic materials including beta-branched chromophores which could be useful for practical EO applications, where both enhanced beta and r(33) values together with chemical and thermal stability are necessary

Adherence to capecitabine in preoperative treatment of stage II and III rectal cancer: do we need to worry?

Background: Preoperative oral capecitabine plus radiotherapy has been progressively adopted in oncology units to provide more convenient care to patients with rectal cancer, but little is known about adherence to this therapy. Patients and methods: Prospective, multicentre observational study in six hospitals in metropolitan Barcelona (Spain), in patients with stage II and III rectal cancer. Assessment of adherence was based on the medical report in the clinical history, a patient questionnaire and a pill count in the pharmacy service upon finalization of treatment. Patients were considered adherent if they had taken 80%-110% of the prescribed treatment. We evaluated clinical variables, adverse effects, anxiety and depression (using the hospital anxiety depression scale [HADS]), and quality of life (EORTC QLQ-30). We analysed adherence-associated variables using a logistic regression model and concordance between adherence measures by means of the modified Kappa index. Results: We included 119 participants. Adherence measures showed little concordance between the assessment methods used: adherence was 100% according to the clinical history, 83.2% according to self-report and 67.9% according to the pill count. In the multivariable analysis, the most relevant variable associated with non-adherence was anxiety prior to treatment (adjusted odds ratio [ORa] 6.96, 95% confidence interval [CI] 1.48-32.7). We did not observe any relevant association between adherence and clinical variables and baseline quality of life parameters. Conclusions: Adherence to short-term oral neoadjuvant treatment in rectal cancer may be a clinical problem, and it should be acknowledged and systematically evaluated by clinicians during treatment. The limited concordance between different measures of adherence highlights the challenges in monitoring it and the need to use different approaches to assess its impact in clinical practice

Long-term retinal PEDF overexpression prevents neovascularization in a murine adult model of retinopathy

Neovascularization associated with diabetic retinopathy (DR) and other ocular disorders is a leading cause of visual impairment and adult-onset blindness. Currently available treatments are merely palliative and offer temporary solutions. Here, we tested the efficacy of antiangiogenic gene transfer in an animal model that mimics the chronic progression of human DR. Adeno-associated viral (AAV) vectors of serotype 2 coding for antiangiogenic Pigment Epithelium Derived Factor (PEDF) were injected in the vitreous of a 1.5 month-old transgenic model of retinopathy that develops progressive neovascularization. A single intravitreal injection led to long-term production of PEDF and to a striking inhibition of intravitreal neovascularization, normalization of retinal capillary density, and prevention of retinal detachment. This was parallel to a reduction in the intraocular levels of Vascular Endothelial Growth Factor (VEGF). Normalization of VEGF was consistent with a downregulation of downstream effectors of angiogenesis, such as the activity of Matrix Metalloproteinases (MMP) 2 and 9 and the content of Connective Tissue Growth Factor (CTGF). These results demonstrate long-term efficacy of AAV-mediated PEDF overexpression in counteracting retinal neovascularization in a relevant animal model, and provides evidence towards the use of this strategy to treat angiogenesis in DR and other chronic proliferative retinal disorders

Assessment of the HER2DX Assay in Patients with ERBB2 -Positive Breast Cancer Treated with Neoadjuvant Paclitaxel, Trastuzumab, and Pertuzumab

Importance: Patients with early-stage ERBB2 (formerly HER2)-positive breast cancer (ERBB2+BC) who experience a pathologic complete response (pCR) after receiving neoadjuvant therapy have favorable survival outcomes. Predicting the likelihood of pCR may help optimize neoadjuvant therapy. Objective: To test the ability of the HER2DX assay to predict the likelihood of pCR in patients with early-stage ERBB2+BC who are receiving deescalated neoadjuvant therapy. Design, Setting, and Participants: In this diagnostic/prognostic study, the HER2DX assay was administered on pretreatment tumor biopsy samples from patients enrolled in the single-arm, multicenter, prospective phase 2 DAPHNe clinical trial who had newly diagnosed stage II to III ERBB2+BC that was treated with neoadjuvant paclitaxel weekly for 12 weeks plus trastuzumab and pertuzumab every 3 weeks for 4 cycles. Interventions and Exposures: The HER2DX assay is a classifier derived from gene expression and limited clinical features that provides 2 independent scores to predict prognosis and likelihood of pCR in patients with early-stage ERBB2+BC. The assay was administered on baseline tumor samples from 80 of 97 patients (82.5%) in the DAPHNe trial. Main Outcomes and Measures: The primary aim was to test the ability of the HER2DX pCR likelihood score (as a continuous variable from 0-100) to predict pCR (ypT0/isN0). Results: Of 80 participants, 79 (98.8%) were women and there were 4 African American (5.0%), 6 Asian (7.5%), 4 Hispanic (5.0%), and 66 White individuals (82.5%); the mean (range) age was 50.3 (26.0-78.0) years. The HER2DX pCR score was significantly associated with pCR (odds ratio, 1.05; 95% CI, 1.03-1.08; P <.001). The pCR rates in the HER2DX high, medium, and low pCR score groups were 92.6%, 63.6%, and 29.0%, respectively (high vs low odds ratio, 30.6; P <.001). The HER2DX pCR score was significantly associated with pCR independently of hormone receptor status, ERBB2 immunohistochemistry score, HER2DX ERBB2 expression score, and prediction analysis of microarray 50 ERBB2-enriched subtype. The correlation between the HER2DX pCR score and prognostic risk score was weak (Pearson coefficient, -0.12). Performance of the risk score could not be assessed due to lack of recurrence events. Conclusions and Relevance: The results of this diagnostic/prognostic study suggest that the HER2DX pCR score assay could predict pCR following treatment with deescalated neoadjuvant paclitaxel with trastuzumab and pertuzumab in patients with early-stage ERBB2+BC. The HER2DX pCR score might guide therapeutic decisions by identifying patients who are candidates for deescalated or escalated approaches

Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery

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