DFT insights into LaFeO3 with Mn substitution: A promising path to energy-efficient magneto-optical applications.

In recent years, the demand for electronic materials has significantly increased, driven by industrial needs and the pursuit of cost-efficient alternatives. This comprehensive study investigates the effects of Mn substitution on LaFeO3 through the implementation of the GGA approach in density functional theory. The research findings demonstrate remarkable consistency with the experimental outcomes reported in the existing literature pertaining to the studied compounds. However, this study unveils novel insights into the mechanical and optical characteristics of the doped structures, which have not been previously reported. The structural stability is rigorously examined through multiple stability criteria, encompassing structural optimization, tests of elastic stability, and enthalpy of formation calculations. Furthermore, the electronic and optical properties of the compounds exhibit exceptional improvements in conductivity and reflectivity as a result of the doping process. The band structure analysis reveals the presence of a Moss-Burstein shift. Investigation of the magnetic properties indicates an increase in the magnetic moment value due to the Fe-Mn degeneracy resulting from increased Mn content. Mechanical analysis of the elastic moduli B, G, and Y demonstrates an enhanced strength and metal-like conductivity, attributed to the induced anharmonicity. Moreover, the internal strain factor suggests a higher degree of bond flexibility, implying potential applications of these compounds in flexible electronics.

Thermal, electro-magnetic and thermoelectric investigation of CoNb1-x Ti x Sn (x = 0, 0.75, 0.5, 1) half-Heusler alloy.

In this work, structural, thermal, electro-magnetic and thermoelectric attributes of CoNb1-x Ti x Sn (x = 0, 0.75, 0.5, 0.25, 0) alloys have been investigated using density functional theory (DFT). The structural reforms, brought to CoNbSn, portray the increase in its rigidity when increasing the Ti content substituted at the Nb site. They also remodel the character of the alloy from semiconducting paramagnetic to half-metallic ferromagnetic nature. By investigating elastic properties that are interlinked with structural optimizations and enthalpy of formation, studied alloys displayed stable structure. Thermoelectric properties such as Seebeck coefficient (S), electrical conductivity (σ/τ) and power factor (S 2 σ/τ), are calculated based on the Boltzmann transport theory. Results revealed that for x = 0.75 in CoNb1-x Ti x Sn, a temperature dependent switch from n-type to p-type is observed. According to the results obtained, CoNb1-x Ti x Sn alloys could have potential thermoelectric applications.

Normal outcome of pregnancy in chronic myeloid leukemia treated with interferon-alpha in 1st trimester: report of 3 cases and review of the literature.

Three patients with chronic myeloid leukemia (CML) in chronic phase received interferon-alpha during pregnancy, starting from the 1st trimester. No maternal complications were reported. The 3 patients delivered normal looking babies apart from one baby who was found to have transient mild thrombocytopenia. Subsequently these children were followed for 30, 12, and 4 months and all had normal growth and development.

Study of colorectal cancer in Qatar.

OBJECTIVE: To study the epidemiology of colorectal cancer in Qatar and compare it with other parts of the world. To collect demographic data on colorectal cancer in Qatar (age and sex distribution) and to collect anatomic pathology data on colorectal cancer in Qatar. METHODS: Retrospective analysis of data collected from hospital records was used to review the incidence and prevalence of colorectal cancer in Qatar. During the period 1994-1998, one hundred and twenty patients with colorectal cancer were seen at Hamad General Hospital. RESULTS: Mean annual incidence was 24 patients/year. Forty-five patients were Qataris and 75 were non Qataris. Of the Qatari patients 26 (58%) were males and 19 (42%) females, male/female ratio was 1.4:1. Nine (20%) patients were under the age of 40 years, the presenting symptoms, physical signs and the stage of the disease were similar to other studies. Descending and sigmoid colon was the most common anatomical site affected. The most common histopathological type was adenocarcinoma. CONCLUSION: The overall incidence of colorectal cancer in Qatar is lower than most of the industrial countries, this may be due to certain factors such as young population, high intake of fruits and vegetables and the life style of the people in Qatar. The incidence in the people below the age of 40 years is higher than industrial countries and, in males due to the demographic structure of the population in Qatar.

The effect of a copper intra-uterine contraceptive device on the microbial ecology of the female genital tract.

Bacteria isolated from 108 intra-uterine contraceptive devices (IUCD) removed from patients with pelvic inflammatory disease (PID), haemorrhage, pregnancy and from asymptomatic women, and from the genital tracts of 66 healthy controls not wearing an IUCD, were studied. No significant differences were found in the types of micro-organisms or isolation rates from IUCDs removed from women in the various clinical groups. The isolation rate of anaerobic bacteria from IUCDs removed from asymptomatic wearers was significantly lower than that from controls, with the exception of the isolation rate of actinomyces which was significantly higher in IUCD wearers and A. israelii was recovered only from IUCDs. The isolation rates of the different bacterial species varied with the duration of the device in utero. The presence of a copper IUCD altered the bacterial flora of the female genital tract. The insertion of such a device and the ecological changes that follow play a crucial role in the development of PID.

PIP: The bacterial flora of the cervix and vagina were examined in 108 patients who had copper IUDs removed and in 66 controls at the Maternity Hospital and Maternal Welfare Clinics in Kuwait. The IUDs removed were the Nova-T, Copper 7, and Cu 250. 15 of the women having IUDs removed had pelvic inflammatory disease; 21 had irregular bleeding; 11 had suprapubic pain, vaginal discharge, or uterine perforation; and 51 were asymptomatic. Actinomyces species, particularly Actinomyces israelii, and Arachnia propionica were isolated from 16 of the IUD wearers but only 2 of the controls. Lactobacillus species were isolated from 10 of the IUD wearers and 25 of the controls. Anaerobic cocci were isolated from 13 device wearers and 12 controls. Except for Actinomyces, anaerobic bacteria were isolated from controls more often than from the IUD wearers. Copper is known to have an antibacterial effect on gram-positive anaerobes, and even Actinomyces was absent from IUD wearers who had worn the device less than a year, i.e., during the period of maximum copper release. Moreover, no significant difference was found in the patients in the different clinical groups. The presence of an IUD does promote colonization of the genital tract by Actinomyces. However, other factors must be considered in the development of pelvic inflammatory disease. The creation of an acidic environment by some bacteria, such as Lactobacillus, may promote the growth of some pathogens, while inhibiting the growth of others. Furthermore, the insertion of an IUD breaches the protective barrier of the cervical mucus, and the IUD tail creates a transmission link into the uterus.