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 CoNb_1-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 CoNb_1-x Ti _x Sn, a temperature dependent switch from n-type to p-type is observed. According to the results obtained, CoNb_1-x Ti _x Sn alloys could have potential thermoelectric applications.

Tuberculosis Presenting as Immune Thrombocytopenia: A case report and review of the literature

Various hematological abnormalities commonly occur in active tuberculosis (TB) but thrombocytopenia is exceed-ingly rare and immune thrombocytopenic purpura (ITP) is reported in only a few cases. A 28-year-old male pre-sented with thrombocytopenia-induced epistaxis and gen-eralized purpura that did not respond to intravenous im-munoglobulin but did resolve after antituberculous treat-ment The characteristics of this rarely documented asso-ciation are reviewed.

Cryptococcal Meningitis in a Patient with Hepatitis C Cirrhosis Presenting with Acute Demyelinating Polyneuropathy of the Guillian-Barre Type

Cryptococcal meningitis is a rare disease that can affect both immunocompetent and immunocompromised patients. A patient presenting with proximal muscle weakness was found to have cryptococcal meningitis. Nerve conduction studies (NCV) confirmed the proximal weakness as acute demyelinating polyradiculoneuropathy. During treatment the patient developed drug-related acute renal failure. He was then treated successfully with an alternative drug. A discussion of cryptococcal. meningitis and its treatment is presented.

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.

Interferon ALFA (INF-α) use during pregnancy: A case report in chronic myeloid leukemia and a review literature

A patient with Philadelphia chromosome positive chronic myeloid leukemia (CML) being treated with INF-a conceived during treatment which continued for the whole course of her pregnancy. A female infant was born at 40th week of gestation and was found to have a platelet count of 56 x 109/L which returned to normal after two weeks.

A literature review of similar cases showed no abnormalities in the infants of mothers receiving INF-a during pregnancy. The safety of INF-a during pregnancy requires further study before its routine use during pregnancy can be recommended.

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.