Artificial Anisotropy in Ge2Sb2Te5 Thin Films after Femtosecond Laser Irradiation

Ge₂Sb₂Te₅ (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density.     

Amniocentesis in pregnant HIV-infected patients. Absence of mother-to-child viral transmission in a series of selected patients

Objectives

To assess the risk of vertical transmission in HIV-infected pregnant women undergoing diagnostic amniocentesis, and to identify possible predictive factors.

Study design

This was a single center retrospective study. The records of 330 HIV-infected pregnant women booked in our antenatal clinic from 31 January 2001 to 31 January 2006 were analyzed. Women who actually underwent diagnostic amniocentesis (“amniocentesis performed” group) were compared to those eligible for amniocentesis but who did not undergo the procedure (“amniocentesis withheld” group).

Results

During the time period, 318 liveborn babies were delivered (9 HIV infected (2.8%)). Thirty-four women (35 fetuses) were eligible for diagnostic amniocentesis. Amniocentesis was performed in 11 (32.4%) of these women (12 fetuses, none infected among the 9 liveborns) and withheld in 23 (67.6%) women. Among the 19 liveborn babies in this latter group, 1 (5.3%) was infected. There was no statistical difference in vertical transmission rate between the whole cohort of HIV-infected pregnant women and the group of women eligible for amniocentesis; or between the women who actually had or did not have an amniocentesis.The women who did undergo amniocentesis all received highly active antiretroviral combination therapy with three drugs; all but two had an undetectable HIV viral load, only one had immunosuppression and none had HCV co-infection.

Conclusion

No vertical transmission was observed in a group of nine liveborn babies after amniocentesis performed in selected HIV-infected pregnant women. In the presence of high genetic risk during pregnancy, amniocentesis can be considered after proper patient counselling.     

Structure,Mechanical and Magnetic Properties of Selective Laser Melted Fe-Si-B Alloy

Original 1CP powder was studied and it was founded that powder material partially consists of the amorphous phase, in which crystallization begins at 450 °C and ends at 575 °C. Selective laser melting parameters were investigated through the track study, and more suitable ones were found: laser power P = 90, 120 W; scanning speed V = 1200 mm/s. Crack-free columnar elements were obtained. The sample obtained with P = 90 W, contains a small amount of amorphous phase. X-ray diffraction of samples shows the presence of α-Fe(Si) and Fe₂B. SEM-image analysis shows the presence of ordered Fe₃Si in both samples. Annealed samples show 40% less microhardness; an annealed sample containing amorphous phase shows higher soft-magnetic properties: 2.5% higher saturation magnetization, 35% higher residual magnetization and 30% higher rectangularity coefficient.     

Factors for Effective Identification of Patients at Nutritional Risk in Clinical Practice: Thematic Analysis of Qualitative Research

IntroductionDespite the high prevalence of malnutrition in patients at all levels of healthcare, early prevention and treatment of malnourished patients are often neglected and overlooked in clinical practice. The aim of this systematic literature review was to identify the factors considered most important by healthcare professionals in the identification and treatment of malnourished patients or those at risk of malnutrition.MethodsA systematic literature review of qualitative research was conducted. Documents published in scientific journals in English from 2011 to 2021 were searched in the PubMed (MEDLINE), CINAHL and ProQuest databases. The results were analysed with a thematic analysis of qualitative research findings.ResultsFrom the search set of 1010 results, 7 sources were included in the final analysis. Factors identified by health professionals as important in the identification and treatment of malnourished patients in clinical practice were grouped into five themes: unclear organizational structure; indefinite structure of nutritional care; poor continuity of nutritional care; lack of knowledge and skills of health professionals; lack of time and human resources.ConclusionsHealth policy must provide resources for nutritional care for patients at all levels of health care on the initiative of the highest professional bodies at the state level. To improve the nutritional care of patients in clinical practice, the management of health care institutions must promote and enable the professional and organizational establishment of clinical nutrition as a regular medical activity of the institution, develop clinical nutritional pathways, and promote evidence-based clinical practice and interprofessional collaboration.