Correction coefficients of distortion and vibration period for buildings due to soil-structure interaction

The present research analyzed the influence of the soil structure interaction (SSI) in buildings, varying geotechnical parameters and height, considering 3 international codes. The responses obtained from the structures taking into account the SSI, were compared with the responses of fixed-base buildings, being the main control variables: the period and the drift. It was determined that the estimated range in which the period of the structure increases is from 30 to 98%, demonstrating the influence of considering soil flexibility. Due to the variability of the responses obtained, an adjustment factor is proposed to predict said amplification of the control variables, depending on the height of the building and the ground

COVID-19. El manejo ambulatorio durante la transmisión comunitaria intensa

The COVID-19, in the scant six months of its presence, has caused a global health crisis, with greater impact in the poorest countries. Currently, there is a better understanding of the clinic of this disease and its relationship with physiopathological phenomena; however, given the high lethality, the major focus of its management has been oriented towards the hospitalized or critical patient. This information and experience is shared in order to achieve and strengthen better care for people affected by COVID-19 from their first symptoms at home, especially at these times of extensive community transmission, where health services are seriously limited in human and material resources. The aim is to (i) avoid complications beyond those caused by the evolution of the disease itself; (ii) determine the appropriate time for patient referral to the hospital and reduce lethality; (iii) reinforce the isolation of cases; and (iv) possibly, decrease the progression to severe disease. It includes outpatient management after hospital discharge, as well as recommendations to consider if health services collapse; indications for when to discharge the patient for return to work, and highlights the importance of telemonitoring for the success of this practice in the current epidemiological context.La COVID-19, en los escasos seis meses de su presencia, ha provocado una crisis sanitaria mundial, con mayor impacto en los países más pobres. En la actualidad, existe un mejor conocimiento de la clínica de esta enfermedad y su relación con los fenómenos fisiopatológicos; sin embargo, dada la alta letalidad, el mayor enfoque de su manejo se ha orientado hacia el paciente hospitalizado o crítico. Esta información y experiencia se comparte con el fin de lograr reforzar una mejor atención a las personas afectadas por la COVID-19 desde sus primeros síntomas en el hogar, especialmente en estos momentos de amplia transmisión en la comunidad, donde los servicios de salud están seriamente limitados en recursos humanos y materiales. El objetivo es: i) evitar complicaciones más allá de las causadas por la propia evolución de la enfermedad;ii) determinar el momento adecuado para la referencia del paciente al hospital y reducir la letalidad; iii) reforzar el aislamiento de los casos; y iv) posiblemente, disminuir la progresión a una enfermedad severa. Incluye el manejo luego del alta hospitalaria, así como recomendaciones para considerar si los servicios de salud colapsan; indicaciones sobre cuándo dar de alta al paciente para que regrese al trabajo, y destaca la importancia del telemonitoreo para el éxito de este manejo en el contexto epidemiológico actual

Natural ventilation for the prevention of airborne contagion.

BACKGROUND: Institutional transmission of airborne infections such as tuberculosis (TB) is an important public health problem, especially in resource-limited settings where protective measures such as negative-pressure isolation rooms are difficult to implement. Natural ventilation may offer a low-cost alternative. Our objective was to investigate the rates, determinants, and effects of natural ventilation in health care settings. METHODS AND FINDINGS: The study was carried out in eight hospitals in Lima, Peru; five were hospitals of "old-fashioned" design built pre-1950, and three of "modern" design, built 1970-1990. In these hospitals 70 naturally ventilated clinical rooms where infectious patients are likely to be encountered were studied. These included respiratory isolation rooms, TB wards, respiratory wards, general medical wards, outpatient consulting rooms, waiting rooms, and emergency departments. These rooms were compared with 12 mechanically ventilated negative-pressure respiratory isolation rooms built post-2000. Ventilation was measured using a carbon dioxide tracer gas technique in 368 experiments. Architectural and environmental variables were measured. For each experiment, infection risk was estimated for TB exposure using the Wells-Riley model of airborne infection. We found that opening windows and doors provided median ventilation of 28 air changes/hour (ACH), more than double that of mechanically ventilated negative-pressure rooms ventilated at the 12 ACH recommended for high-risk areas, and 18 times that with windows and doors closed (p < 0.001). Facilities built more than 50 years ago, characterised by large windows and high ceilings, had greater ventilation than modern naturally ventilated rooms (40 versus 17 ACH; p < 0.001). Even within the lowest quartile of wind speeds, natural ventilation exceeded mechanical (p < 0.001). The Wells-Riley airborne infection model predicted that in mechanically ventilated rooms 39% of susceptible individuals would become infected following 24 h of exposure to untreated TB patients of infectiousness characterised in a well-documented outbreak. This infection rate compared with 33% in modern and 11% in pre-1950 naturally ventilated facilities with windows and doors open. CONCLUSIONS: Opening windows and doors maximises natural ventilation so that the risk of airborne contagion is much lower than with costly, maintenance-requiring mechanical ventilation systems. Old-fashioned clinical areas with high ceilings and large windows provide greatest protection. Natural ventilation costs little and is maintenance free, and is particularly suited to limited-resource settings and tropical climates, where the burden of TB and institutional TB transmission is highest. In settings where respiratory isolation is difficult and climate permits, windows and doors should be opened to reduce the risk of airborne contagion

Breaking Waves Offshore: Measurements and Modeling of Energy Dissipation

In the presence of strong winds, ocean surface waves dissipate significant amounts of energy by breaking. Here, breaking rates and wave-following turbulent dissipation rate measurements are compared with numerical WAVEWATCH III estimates of bulk energy dissipation. At high winds, the measurements suggest that turbulent dissipation becomes saturated, however the modeled bulk dissipation continues to increase as a cubic function of wind speed. Similarly, the mean square slope (i.e., the steepness) of the measured waves becomes saturated, while the modeled mean squared slope grows linearly with wind speed. Limited observations of breaker fraction suggest a linear relation with wind speed. Finally, the model skill for estimating basic parameters such as significant wave height is shown to be sensitive to the dissipation rate, indicating that the model skill may be compromised under energetic conditions

Search for Intermediate Mass Magnetic Monopoles and Nuclearites with the SLIM experiment

SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It is devoted to the search for intermediate mass magnetic monopoles (107-1013 GeV/c2) and nuclearites in the cosmic radiation using stacks of CR39 and Makrofol nuclear track detectors. In four years of operation it will reach a sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of the calibration of CR39 and Makrofol and the analysis of a first sample of the exposed detector.Comment: Presented at the 22nd ICNTS, Barcelona 200

Search for massive rare particles with the SLIM experiment

The search for magnetic monopoles in the cosmic radiation remains one of the main aims of non-accelerator particle astrophysics. Experiments at high altitude allow lower mass thresholds with respect to detectors at sea level or underground. The SLIM experiment is a large array of nuclear track detectors at the Chacaltaya High Altitude Laboratory (5290 m a.s.l.). The results from the analysis of 171 m$^2$ exposed for more than 3.5 y are here reported. The completion of the analysis of the whole detector will allow to set the lowest flux upper limit for Magnetic Monopoles in the mass range 10$^5$ - 10$^{12}$ GeV. The experiment is also sensitive to SQM nuggets and Q-balls, which are possible Dark Matter candidates.Comment: Presented at the 29-th ICRC, Pune, India (2005

Impact of infection control measures to control an outbreak of multidrug-resistant tuberculosis in a human immunodeficiency virus ward, Peru

Multidrug-resistant tuberculosis (MDRTB) rates in a human immunodeficiency virus (HIV) care facility increased by the year 2000-56% of TB cases, eight times the national MDRTB rate. We reported the effect of tuberculosis infection control measures that were introduced in 2001 and that consisted of 1) building a respiratory isolation ward with mechanical ventilation, 2) triage segregation of patients, 3) relocation of waiting room to outdoors, 4) rapid sputum smear microscopy, and 5) culture/drug-susceptibility testing with the microscopic-observation drug-susceptibility assay. Records pertaining to patients attending the study site between 1997 and 2004 were reviewed. Six hundred and fifty five HIV/TB-coinfected patients (mean age 33 years, 79% male) who attended the service during the study period were included. After the intervention, MDRTB rates declined to 20% of TB cases by the year 2004 (P = 0.01). Extremely limited access to antiretroviral therapy and specific MDRTB therapy did not change during this period, and concurrently, national MDRTB prevalence increased, implying that the infection control measures caused the fall in MDRTB rates. The infection control measures were estimated to have cost US$91,031 while preventing 97 MDRTB cases, potentially saving US$1,430,026. Thus, this intervention significantly reduced MDRTB within an HIV care facility in this resource-constrained setting and should be cost-effective

Anti-inflammatory, pro-proliferative and antimicrobial potential of the compounds isolated from Daemonorops draco (Willd.) Blume

Ethno-pharmacological relevance: Daemonorops draco (D. draco) commonly known as “Dragon's blood” is one of the most used plants by Momok, Anak Dalam and Talang Mamak tribes from Indonesia as a remedy for wound healing. Aim of the study: This study aimed to identify the extract, fractions and compounds responsible for the anti-inflammatory and pro-proliferative activities of the D. draco resin. Additionally, the antimicrobial activity against two bacteria and one yeast species was analysed. Materials and methods: Bio-guided isolation of compounds with anti-inflammatory, pro-proliferative and antimicrobial activities from the D. draco resin was carried out by measuring: the inhibition of NF-κB and activation of Nrf2 in THP-1, HaCaT, NIH-3T3 cells; cell proliferation in NIH-3T3 and HaCaT cells; and the antimicrobial effect on E. coli, S. aureus and C. albicans. Results: Guided isolation by bioassay gave rise to the isolation and characterisation by nuclear magnetic resonance and mass spectrometry of three compounds: 1 (Bexarotene), 2 (Taspine) and 3 (2-hydroxy-1-naphthaldehyde isonicotinoyl hydrazone). All compounds showed NF-κB inhibitory activity with IC50 values of 0.10–0.13, 0.22–0.24 and 3.75–4.78 μM, respectively, while the positive control, Celastrol, had an IC50 of 7.96 μM. Likewise, all compounds showed an activating effect of Nrf2 with EC50 values of 5.34–5.43, 163.20–169.20 and 300.82–315.56 nM, respectively, while the positive control, CDDO-Me, had an EC50 of 0.11 nM. In addition, concerning the pro-proliferative activity, compound 1 (IC50 = 8.62–8.71 nM) showed a capacity of 100%, compound 2 (IC50 = 166–171 nM) showed a capacity of 75%, and compound 3 (IC50 = 469–486 nM) showed a capacity of 65%, while FSB 10% (positive control) had a pro-proliferative activity of 100% in the NIH3T3 cell lines (fibroblasts) and HaCaT (keratinocytes). Finally, all the compounds showed antimicrobial activity with MIC values of 0.12–0.16, 0.31–0.39 and 3.96–3.99 μM, respectively, in S. aureus, E. coli and C. albicans strains, while the positive control, Ofloxacin, had a MIC of 27.65 μM. Conclusion: This study managed to isolate, for the first time, three compounds (Bexarotene, Taspine and 2-hydroxy-1-naphthaldehyde isonicotinoyl hydrazone) from the resin of D. draco, with anti-inflammatory, and pro-proliferative as well as antimicrobial activitie

Protocol for studying cough frequency in people with pulmonary tuberculosis.

INTRODUCTION: Cough is a key symptom of tuberculosis (TB) as well as the main cause of transmission. However, a recent literature review found that cough frequency (number of coughs per hour) in patients with TB has only been studied once, in 1969. The main aim of this study is to describe cough frequency patterns before and after the start of TB treatment and to determine baseline factors that affect cough frequency in these patients. Secondarily, we will evaluate the correlation between cough frequency and TB microbiological resolution. METHODS: This study will select participants with culture confirmed TB from 2 tertiary hospitals in Lima, Peru. We estimated that a sample size of 107 patients was sufficient to detect clinically significant changes in cough frequency. Participants will initially be evaluated through questionnaires, radiology, microscopic observation drug susceptibility broth TB-culture, auramine smear microscopy and cough recordings. This cohort will be followed for the initial 60 days of anti-TB treatment, and throughout the study several microbiological samples as well as 24 h recordings will be collected. We will describe the variability of cough episodes and determine its association with baseline laboratory parameters of pulmonary TB. In addition, we will analyse the reduction of cough frequency in predicting TB cure, adjusted for potential confounders. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the ethics committees at each participating hospital in Lima, Peru, Asociación Benéfica PRISMA in Lima, Peru, the Universidad Peruana Cayetano Heredia in Lima, Peru and Johns Hopkins University in Baltimore, USA. We aim to publish and disseminate our findings in peer-reviewed journals. We also expect to create and maintain an online repository for TB cough sounds as well as the statistical analysis employed

Impacto del Confinamiento por COVID-19 en estudiantes universitarios

El COVID-19 se expandió rápidamente en todo el mundo y al no existir el tratamiento del caso, se impuso como única opción para evitar el contagio, la prevención con mascarillas y el distanciamiento social. Su expansión obligó a que el 11 de marzo de 2020, la Organización Mundial de la Salud (OMS), la declare como pandemia global. El objetivo de la investigación fue determinar el impacto del COVID-19 en los estudiantes de VIII ciclo de Idioma Extranjero de la Facultad de Educación, Comunicación y Humanidades de la Universidad Nacional Jorge Basadre Grohmann. La investigación se desarrolló utilizando métodos cuantitativos, considerando cuatro dimensiones: factor económico, factor salud, factor socioafectivo y educación. De una población de 56 estudiantes matriculados, se seleccionó, por conveniencia, una muestra conformada por 42 estudiantes. Los datos fueron analizados con el programa estadístico SPSS. Se concluye que por pandemia el 31.0 % perdieron el empleo; los afectados por la reducción de sueldo conforman el 33.3 %, y contrajeron el virus del COVID-19 el 69.0 %; los vínculos afectivos durante la pandemia se fortalecieron, donde el 45.2% precisa que hubo mayor acercamiento entre los integrantes de la familia, comparten los quehaceres en el hogar el 33.3 %, finalmente los estudiantes consideran que las clases virtuales son estresante y agotador