RESUMEN
A NaCeP2O7 compound was successfully synthesized by a high-temperature reaction with the solid-state method. Analyzing the XRD pattern, of the studied compound, confirms the orthorhombic phase with the Pnma space group. The examination of SEM images reveals that the majority of grains are around 500 to 900 nm with a uniform distribution. As for the EDXS analysis, all chemical elements were detected and found in the appropriate ratio. The curves of temperature-dependent imaginary modulus M'' versus angular frequency reveal the presence of one peak at each temperature, proving that the dominant contribution is associated with the grains. The frequency dependence of the conductivity of alternating current is explained using Jonscher's law. The close values of the activation energies obtained from the jump frequency and extracted from the dielectric relaxation of the modulus spectra, as well as from the continuous conductivity imply that the transport takes place by the Na+ ions hopping mechanism. The charge carrier concentration in the title compound has been evaluated and shown to be independent of temperature. The exponent s increases with the increase in temperature; this behavior proves that the non-overlapping small polaron tunneling (NSPT) is the appropriate conduction mechanism model.
RESUMEN
Along with morphological and structural studies, the temperature and frequency dependence of the electrical and dielectric properties of the CH3NH3HgCl3 (MATM) compound was investigated and analyzed. SEM/EDS and XRPD analyses proved the purity, composition, and perovskite structure of the MATM. DSC analysis reveals the existence of an order-disorder phase transition of a first-order type at about 342 ± 2 K and 320 ± 1 K (heating and cooling, respectively), attributed to the disorder of [CH3NH3]+ ions. The overall results of the electrical study provide arguments for the ferroelectric nature of this compound and aim to broaden the current knowledge on the thermally activated conduction mechanisms of the studied compound via impedance spectroscopy. The electrical investigations have shown the dominant transport mechanisms in different frequency and temperature ranges, proposing the CBH model in the ferroelectric phase and the NSPT model in the paraelectric phase. The temperature dependence of the dielectric study reveals the classic ferroelectric nature of the MATM. As for the frequency dependence, it correlates the frequency-dispersive dielectric spectra with the conduction mechanisms and their relaxation processes.
RESUMEN
COVID-19 is an exceptional public healthcare emergency that affected all countries. The corona virus pandemic has made the treatment of all cancers difficult. This international phenomenon represents an outbreak in medicine and this situation is a major issue for all patients, whether they are infected with the virus or not. Colorectal cancer is one of the most common malignant tumors of the digestive tract which needs special multidisciplinary care. Treatment modalities including chemotherapy and targeted therapies can weaken the immune system and then cause serious or lethal coronavirus infections. This document gives an idea about how we dealt to protect patients with colorectal cancer at Salah Azaiez Institute during COVID 19 pandemic.
Asunto(s)
COVID-19/prevención & control , Neoplasias Colorrectales/terapia , Control de Infecciones/métodos , Protocolos de Quimioterapia Combinada Antineoplásica , Instituciones Oncológicas , Humanos , Huésped Inmunocomprometido , SARS-CoV-2 , TúnezRESUMEN
INTRODUCTION: Colorectal cancer (CRC) is at present the third most common malignancy in the world. With changes in lifestyle its incidence and mortality have increased during last decades. AIM: To explore the association between red meat, processed meat and risk of colorectal cancer. METHODS: We performed a case-control study, conducted from February to March 2019 at Salah Azaiez institute. One hundred and two subjects were enrolled. RESULTS: The case group included 52.9% males and 47.1% females. The control group enrolled 49%males and 51% females. The median age was 56 years old in the two groups. 63% of patients were stage I-III disease and 37% have a metastatic disease. The mean Body mass index was 24,76 Kg/m2 in CRC group was 27,39Kg/m2 in controls. CRC cases were more likely than controls to have a family history of CRC and a lower education level. There was a significant difference between cases and controls for socio-economic level and geographic origin. Ninety point two percent of cases and 76.5% of controls consume red meats, no significant association was observed between moderate red meat intake and colorectal cancer risk (p 0,063). However, a high total day meat consumption (> 100 g) was significantly associated with a high risk of CRC compared to low consumption ( <50 g) ( p=0.023). In contrast no significant association was observed when comparing all cooking methods of meet. 51% of cases and 23,5% of controls intake processed meats. Processed meat was positively associated with CRC (p 0,004). CONCLUSION: Our findings suggest that higher consumptions of red meat, the consumption of industrially processed meat increased the risk of CRC.