Frequency correlation requirements on the biphoton wavefunction in an induced coherence experiment between separate sources

There is renewed interest in using the coherence between beams generated in separate down-converter sources for new applications in imaging, spectroscopy, microscopy and optical coherence tomography (OCT). These schemes make use of continuous wave (CW) pumping in the low parametric gain regime, which produces frequency correlations, and frequency entanglement, between signal-idler pairs generated in each single source. But can induced coherence still be observed if there is no frequency correlation, so the biphoton wavefunction is factorable? We will show that this is the case, and this might be an advantage for OCT applications. High axial resolution requires a large bandwidth. For CW pumping this requires the use of short nonlinear crystals. This is detrimental since short crystals generate small photon fluxes. We show that the use of ultrashort pump pulses allows improving axial resolution even for long crystal that produce higher photon fluxes

Estimación de la resistencia in situ de un HAC mediante la resistencia de probetas testigo

El presente trabajo tiene como objetivo establecer algunos factores de corrección que afectan el resultado de la resistencia de las probetas testigo a fin de pronosticar la resistencia a compresión in situ. Para el cumplimiento de dicho objetivo se han fabricado 30 bloques de 500x500x1000 mm en Hormigón Autocompactante (HAC) cubriendo un amplio rango de resistencias de 20 MPa a 80 MPa. De estos bloques se han extraído 360 probetas testigo con variaciones en el diámetro (50 mm, 75 mm y 100 mm), en la dirección de extracción (horizontal y vertical) y en la condición de humedad secas y húmedas). Para el pronóstico de la resistencia in situ se ha considerado el principio de superposición de efectos establecido en normas como la ACI-214.4R-10. En este sentido, para las condiciones del ensayo, se han cuantificado mediante factores de corrección los efectos generados por el diámetro y la condición de humedad del testigo en el momento del ensayo y por el nivel resistente del hormigón. Además, se ha valorado de manera conjunta la influencia de las variables intrínsecas de las probetas testigo, tales como, microfisuración, efecto pared, condiciones de contorno, etc. Los resultados indicaron que algunos factores de corrección utilizados para pronosticar la resistencia in situ, inciden de forma muy diferente en los HAC con respecto a los hormigones vibrados tradicionalmente (HVT)

Effects of introgressed 4Nv Aegilops ventricosa chromosome on yield and yield components in bread wheat.

Effects of introgressed 4Nv Aegilops ventricosa chromosome on yield and yield components in bread whea

Characterization of LR-115 Type 2 Detectors for Monitoring Indoor Radon 222: Determination of the Calibration Factor

The city of Lima, capital of Peru, has about 11 million inhabitants. Lima has no records about the indoor Radon 222 concentration levels in dwellings. Hereby, we are planning to register the indoor radon concentrations in Lima and in other cities of Peru in the next three years. First, we will determine the calibration factor for the detectors which will be used in our measurements. For this purpose, Solid State Nuclear Tracks Detectors of nitrocellulose nitrate (LR-115 type 2) were used.The calibration process using a Radium 226 source was described to obtain the calibration factor. Linear response in tracks number was found in relation with irradiation time and its stability after time at the calibration chamber

Hospitalizations and mortality of patients with heart failure in the COVID-19 era in Peru

Objectives: The worldwide heart failure (HF) prevalence is 8.52 per 1000 inhabitants, with a global economic burden of 346.17 billion dollars. With the COVID-19 pandemic, the focus of medical care has changed to treating the morbidity and mortality of patients with COVID-19 and reducing medical procedures or visits to patients with HF, with the impact being greater in low- and middle-income countries. Methods: We performed an interrupted time series analysis of HF to determine the changes in the trend of hospitalizations and in-hospital mortality of HF patients before and after the mandatory lockdown in Peru. Results: A total of 18,514 adults were included in the analysis. Monthly hospital admissions immediately decreased by 599 (95% confidence interval [CI]: 113 to 1085) and the difference in slope before and after the lockdown was 6.4 hospital admissions (95% CI: −4 to 18). In-hospital mortality increased by 18% (95% CI: −8%–43%) and the difference in slope before and after the lockdown was −0.3% (95% CI: −0.9%–0.25%). Conclusions: There was a reduction in hospitalizations and an increase in the in-hospital mortality of patients with HF before and after the mandatory lockdown due to the COVID-19 pandemic in Peru.Revisión por pare

Nitric oxide modulates interleukin-2-induced proliferation in CTLL-2 cells

The role of the L-arginine–nitric oxide metabolic pathway was explored for interleukin-2-induced proliferation in the cytotoxic T lymphocyte clone CTLL-2. Specific inhibition of nitric oxide synthase significantly diminished, in a concentration-dependent manner, 3H-thymidine uptake of CTLL-2 cells in response to different concentrations of interleukin 2. Withdrawal of L-arginine from culture medium resulted as potent as the higher inhibition obtained when blocking nitric oxide synthase with L-arginine analogues. Furthermore, intermedial concentrations of Larginine and exogenous nitric oxide donors were found for achieving optimal IL2-induced proliferation of CTLL-2. These findings prompted us to suggest that intra- and/or inter-cellular nitric oxide signalling may contribute to the modulation of the IL2 mitogenic effect upon cytotoxic T lymphocytes

Food Insecurity and Mental Health among Venezuelan Migrants and Refugees Living in Peru: Secondary Data Analysis of a Cross-Sectional Survey

The objective of this study was to analyze the association between food insecurity and mental health in Venezuelan migrants and refugees residing in Peru using data from the Survey Directed at the Venezuelan Population Residing in the Country (ENPOVE) conducted in 2022. The analysis included 7739 Venezuelan adults. The presence of mental health problems was self-reported, and household food insecurity was measured using the Food Insecurity Experience Scale. The study found that 4 out of 10 participants lived in households with moderate to severe food insecurity, and around 10% reported experiencing some mental health problem in the last month. The study identified a positive association between living in households with moderate to severe food insecurity and having some mental health problem compared to living in households without food insecurity. The findings suggest that food insecurity is a common problem among the Venezuelan migrant population residing in Peru, and measures are required to address this problem and mitigate its consequences on mental health and other health problems. The study highlights the need for international organizations to provide assistance and support to these populations and ensure adequate and sustainable follow-up of food insecurity at the national level. It is also necessary to implement early detection tests for mental health problems in the migrant population, especially in individuals exposed to food insecurity. This study provides relevant evidence for addressing public health in the Venezuelan migrant population residing in Peru.Revisión por pare