Effects of Deposition Temperature and Working Pressure on the Thermal and Nanomechanical Performances of Stoichiometric Cu3N: An Adaptable Material for Photovoltaic Applications.

The pursuit of efficient, profitable, and ecofriendly materials has defined solar cell research from its inception to today. Some materials, such as copper nitride (Cu3N), show great promise for promoting sustainable solar technologies. This study employed reactive radio-frequency magnetron sputtering using a pure nitrogen environment to fabricate quality Cu3N thin films to evaluate how both temperature and gas working pressure affect their solar absorption capabilities. Several characterization techniques, including X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), Raman spectroscopy, scanning electron microscopy (SEM), nanoindentation, and photothermal deflection spectroscopy (PDS), were used to determine the main properties of the thin films. The results indicated that, at room temperature, it is possible to obtain a material that is close to stoichiometric Cu3N material (Cu/N ratio ≈ 3) with (100) preferred orientation, which was lost as the substrate temperature increases, demonstrating a clear influence of this parameter on the film structure attributed to nitrogen re-emission at higher temperatures. Raman microscopy confirmed the formation of Cu-N bonds within the 628-637 cm-1 range. In addition, the temperature and the working pressure significantly also influence the film hardness and the grain size, affecting the elastic modulus. Finally, the optical properties revealed suitable properties at lower temperatures, including bandgap values, refractive index, and Urbach energy. These findings underscore the potential of Cu3N thin films in solar energy due to their advantageous properties and resilience against defects. This research paves the way for future advancements in efficient and sustainable solar technologies.

Synthesis and stimulated luminescence property of Zn(BO2)2:Tb3.

Zinc borate, Zn(BO2)2, doped with different concentrations of terbium (0.5-8mol%) was synthesized and polycrystalline samples were characterized by Scanning Electron Microscopy and X-Ray Diffraction. The Zn(BO2)2 was formed in the pure samples sintered at 750 and 800°C which has the body centered cubic structure, and a ZnB4O7 primitive orthorhombic phase was present. The thermoluminescent intensity was dependents on the thermal treatment (250-500°C) and also on the impurity concentration. The linear dose-response was obtained between 0.022-27.7Gy and 0.5-50Gy when the samples were exposed to beta and gamma radiation, respectively. The complex structure of the glow curves was analyzed by the Computerized Glow Curve Deconvolution method. The kinetics parameters were calculated assuming the general order kinetics model describing accurately the TL process. The glow curves of Tb3+-doped zinc borate phosphor were well deconvolved by six glow peaks. Zinc borate with 8mol% of impurity concentration exhibited an intense radioluminescent emission. The radioluminescent spectra show their maximum bands at 370, 490, 545 and 700nm related to the terbium ion in the zinc borate. These obtained results suggest that the terbium doped zinc borate is a promising phosphor for use in radiation dosimetry because of its high TL sensitivity to the ionizing radiation.

The PI3K inhibitor GDC-0941 combines with existing clinical regimens for superior activity in multiple myeloma.

The phosphatidylinositol 3'-kinase (PI3K) pathway is dysregulated in multiple myeloma (MM); we therefore tested a highly selective class I PI3K inhibitor, GDC-0941, for anti-myeloma activity. Functional and mechanistic studies were first performed in MM cell lines, then extended to primary MM patient samples cultured in vitro. GDC-0941 was then assessed as a single agent and in various combinations in myeloma tumor xenograft models. We show p110 α and ß are the predominant PI3K catalytic subunits in MM and that a highly selective class I PI3K inhibitor, GDC-0941, has robust activity as a single agent to induce cell cycle arrest and apoptosis of both MM cell lines and patient myeloma cells. Mechanistic studies revealed an induction of cell cycle arrest at G0/G1, with decreased phospho-FoxO1/3a levels, decreased cyclin D1 and c-myc expression, and an increase in the cell cycle inhibitor, p27kip. Induction of apoptosis correlated with increased expression of the pro-apoptotic BH3-only protein BIM, cleaved caspase 3 and cleaved poly (ADP-ribose) polymerase (PARP). In vitro, GDC-0941 synergized with dexamethasone (Dex) and lenalidomide (combination index values of 0.3-0.4 and 0.4-0.8, respectively); in vivo GDC-0941 has anti-myeloma activity and significantly increases the activity of the standard of care agents in several murine xenograft tumor models (additional tumor growth inhibition of 37-53% (Dex) and 22-72% (lenalidomide)). These data provide a clear therapeutic hypothesis for the inhibition of PI3K and provide a rationale for clinical development of GDC-0941 in myeloma.

Marginal validity of syndromic management for reproductive tract infections among pregnant women in Jamaica.

We assessed the validity of a syndromic case management approach for reproductive tract infections (RTIs) among 371 pregnant women attending antenatal care facilities in Kingston, Jamaica, using an algorithm previously validated in high-risk Jamaican women. For our antenatal attenders, the algorithm had low sensitivities for all RTIs (66.7% for cervicitis, 35.4% for trichomoniasis, 11.1% for bacterial vaginosis (BV) and 24% for candidiasis). Specificities for BV (88.9%) and candidiasis (81.1%) were higher than for cervicitis (62.8%) and trichomoniasis (68.5%). The positive predictive values were lower than 36% for all diagnoses, especially BV (6.9%). Syndromic management of RTIs in pregnant women was problematic using a clinical algorithm that had worked well for high-risk women. Syndromic management for RTIs in Jamaican antenatal clinics is only a temporary solution until more simple and affordable diagnostic tests for RTIs are developed and/or until laboratory support and clinical care can be upgraded at antenatal clinics.

Vaginal infections in pregnant women in Jamaica: prevalence and risk factors.

Trichomoniasis, bacterial vaginosis (BV) and candidiasis are reproductive tract infections (RTIs) of the vagina. We conducted a cross-sectional study in 4 prenatal clinics in Kingston, Jamaica, to estimate the prevalence of these infections and the risk factors that may facilitate their transmission among pregnant women. Of the 269 women studied, 18.0% had culture-positive trichomoniasis, 44.1% had BV (Nugent score > or = 7) and 30.7% were positive for candidiasis by wet mount. A multiple logistic regression analysis showed that having a malodorous discharge was associated with trichomoniasis (odd ratios [OR]=3.9, confidence intervals [CI]=1.04-14.7) and BV (OR=3.4, CI=1.3-8.7). Women who took action to prevent HIV infection had lower BV prevalence (OR=0.34, CI=0.12-0.98). Women who were employed were less likely to have any of the infections (OR=0.61, CI=0.36-1.03). The strong association of a symptomatic presentation with trichomoniasis and BV suggests the merit of considering syndromic management of vaginitis in this population.