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Benjamin Valdez-Salas,1,2 Ernesto Beltran-Partida,1,2 Nelson Cheng,3 Jorge Salvador-Carlos,2 Ernesto Alonso Valdez-Salas,1 Mario Curiel-Alvarez,2 Roberto Ibarra-Wiley2 1Laboratorio de Biología Molecular y Cáncer, Instituto de Ingeniería, Universidad Autónoma de Baja California, Mexicali, Baja California, Mexico; 2Laboratorio de Corrosión y Materiales Avanzados, Instituto de Ingeniería, Universidad Autónoma de Baja California, Mexicali, Baja California, Mexico; 3Magna International Pte Ltd, SingaporeCorrespondence: Benjamin Valdez-Salas Tel/Fax +526865664154 Ext. 150Email benval@uabc.edu.mxBackground: The COVID-19 pandemic is requesting highly effective protective personnel equipment, mainly for healthcare professionals. However, the current demand has exceeded the supply chain and, consequently, shortage of essential medical materials, such as surgical masks. Due to these alarming limitations, it is crucial to develop effective means of disinfection, reusing, and thereby applying antimicrobial shielding protection to the clinical supplies.Purpose: Therefore, in this work, we developed a novel, economical, and straightforward approach to promote antimicrobial activity to surgical masks by impregnating silver nanoparticles (AgNPs).Methods: Our strategy consisted of fabricating a new alcohol disinfectant formulation combining special surfactants and AgNPs, which is demonstrated to be extensively effective against a broad number of microbial surrogates of SARS-CoV-2.Results: The present nano-formula reported a superior microbial reduction of 99.999% against a wide number of microorganisms. Furthermore, the enveloped H5N1 virus was wholly inactivated after 15 min of disinfection. Far more attractive, the current method for reusing surgical masks did not show outcomes of detrimental amendments, suggesting that the protocol does not alter the filtration effectiveness.Conclusion: The nano-disinfectant provides a valuable strategy for effective decontamination, reuse, and even antimicrobial promotion to surgical masks for frontline clinical personnel.Keywords: surgical mask, antimicrobial, SARS-CoV-2, nanobiotechnology, COVID-19, nanoparticles

Injury and dropout rates during rodwork training appear to reflect difficulties encountered by apprentices adapting to increased physical demands of tying on slab, one of the rodworking tasks with the highest injury risk. Because experience influences work strategies, and consequently the risk of developing musculoskeletal disorders (MSDs), this study aimed to identify differences in work practices associated with tying rebar on slab, potentially relevant to back MSD development, in experienced and inexperienced rodworkers. Fourteen male rodworkers were recruited from either experienced (>2 years experience post apprenticeship), or inexperienced (<6 months experience) groups. Both tied an area with rebar laid on the ground. Trunk flexion/extension angles were measured. L4/L5 moments were estimated from T9 Erector Spinae EMG. Experienced workers were found to spend longer periods of time in trunk flexed postures, with lower peak L4/L5 moments. Our findings revealed practices associated with each group might have different implications on back health., (Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

Objectives: The objective of this study was to evaluate the efficacy of three ergonomic assessment tools (EATs) (RULA, REBA and Strain Index (SI)) in the assessment of non-fixed work through comparison to four occupationally relevant Borg 10 psychophysical scales: Lifting Effort, Grasping Effort, Wrist Discomfort, and Low Back Discomfort., Participants: Fourteen male rodworkers participated in this study. The participants had at least six months experience and had no musculoskeletal injuries in the six months preceding their participation., Methods: Psychophysical scale and video data were collected while participants performed non-fixed work on construction sites. Psychophysical and EAT outcome measure scores were calculated for a shortlist of tasks., Results: It was found that the perceived Grasping Effort and Wrist Discomfort scales differentiated between the WMSD risks associated with rodworking tasks and SI was found to be more effective than RULA and REBA in the assessment of non-fixed work WMSD risks., Conclusions: Based on the findings of this study, it is suggested that SI be further evaluated for its ability to assess WMSD risks associated with non-fixed work tasks. SI presents results that have practical application to non-fixed occupations and differentiate between tasks based on the WMSD risks associated with the tasks.

This study investigated the relation between vegetation reflectance and elevated concentrations of the metals Ni, Cd, Cu, Zn and Pb in river floodplain soils. High-resolution vegetation reflectance spectra in the visible to near-infrared (400-1350 nm) were obtained using a field radiometer. The relations were evaluated using simple linear regression in combination with two spectral vegetation indices: the Difference Vegetation Index (DVI) and the Red-Edge Position (REP). In addition, a multivariate regression approach using partial least squares (PLS) regression was adopted. The three methods achieved comparable results. The best R(2) values for the relation between metals concentrations and vegetation reflectance were obtained for grass vegetation and ranged from 0.50 to 0.73. Herbaceous species displayed a larger deviation from the established relationships, resulting in lower R(2) values and larger cross-validation errors. The results corroborate the potential of hyperspectral remote sensing to contribute to the survey of elevated metal concentrations in floodplain soils under grassland using the spectral response of the vegetation as an indicator. Additional constraints will, however, have to be taken into account, as results are resolution- and location-dependent.

Both DR4 and DR5 have recently been identified as membrane death receptors that are activated by their ligand TRAIL to engage the intracellular apoptotic machinery. TRID (also named as TRAIL-R3) is an antagonist decoy receptor and lacks the cytoplasmic death domain. TRID protects from TRAIL-induced apoptosis by competing with DR4 and DR5 for binding to TRAIL. TRID has been shown to be overexpressed in normal human tissues but not in malignantly transformed cell lines. DR5 is a p53-regulated gene and we have recently reported that DR5 expression is induced in response to genotoxic stress in both a p53-dependent and independent manner (Sheikh et al., 1998). In the current study, we demonstrate that TRID gene expression is also induced by the genotoxic agents ionizing radiation and methyl methanesulfonate (MMS) in predominantly p53 wild-type cells, whereas UV-irradiation does not induce TRID gene expression. Consistent with these results, exogenous wild-type p53 also upregulates the expression of endogenous TRID in p53-null cells. Thus, TRID appears to be a p53 target gene that is regulated by genotoxic stress in a p53-dependent manner. Using primary gastrointestinal tract (GIT) tumors and their matching normal tissue, we also demonstrate for the first time that TRID expression is enhanced in primary tumors of the GIT. It is, therefore, possible that TRID overexpressing GIT tumors may gain a selective growth advantage by escaping from TRAIL-induced apoptosis.