Effectiveness Cost of HIV rapid tests in Italy and Europe

In the United States, about a quarter of the estimated 1.1 million people living with human immunodeficiency virus (HIV) are not aware of their HIV status. HIV tests in communities with outreach settings can be an effective strategy to identify people with unidentified HIV infection. The spread of innovative rapid tests represents an additional opportunity in the field of HIV prevention. HIV rapid tests represent an excellent diagnostic tool to reach the rural or poor population where accessibility to test is limited or populations with high-risk infection. Cost-effectiveness point of view, this service always has the potential for early diagnosis by affecting lower hospital spending, preventing clinically aggravated cases with decreased CD4 and acquired immunodeficiency. The study analyses the characteristics of rapid tests by evaluating what can be used in Europe and Italy from case studies. The sensitivity, specificity and project needs are the main factors of choice in testing project

On the Role of Support in Metallic Heterogeneous Catalysis: A Study of Unsupported Nickel\u2013Cobalt Alloy Nanoparticles in Ethanol Steam Reforming

(Co, Ni) bimetallic nanoparticles have been prepared by reducing Ni and Co chloride solutions with sodium borohydride. The obtained materials have been characterized as cast and/or after annealing by means of XRD, magnetic measurements, IR spectroscopy, FE-SEM and TEM microscopies. The resulting nanomaterials, originally amorphous, crystallize into the cubic structure cF4-Cu as homogeneous (Co, Ni) solid solution alloy and with the additional presence of Boron containing phases due to the residual preparation impurities. The bimetallic nanoparticles are active in ethanol conversion in the presence of steam. For low Boron catalysts, the addition of Nickel to Cobalt nanoparticles improves the catalytic activity in ethanol steam reforming allowing yields as high as 87% at 773 K, at high space velocities (GHSV 324,000 h 121 ). The performances of the catalytic unsupported nanoparticles with a Ni/Co atomic ratio equal to 0.26 appear to be better than those of conventional supported catalysts. The state of Boron impurities affect catalytic activity of bimetallic (Co, Ni) NPs. Carbonaceous materials, such as carbon nanotubes and graphitic carbon, form on the catalyst surface upon reaction. Graphical Abstract: [Figure not available: see fulltext.]

Near-infrared emitting colloidal PbS nanoplatelets : lateral size control and optical spectroscopy

Two dimensional (2D) colloidal PbS nano platelets (NPLs) with a thickness of 1.8-2.8 nm have been synthesized using a single-molecule precursor approach with lead octadecylxanthate. The lateral dimensions were tuned by varying the reaction temperature, growth time, and capping ligands. Transmission electron microscopy and X-ray diffraction reveal that the NPLs have an orthorhombic crystal structure rather than the rocksalt phase usually reported for bulk and nanostructured PbS. The 1.8 nm thickness, in combination with the tunable lateral dimensions, results in a blue-shifted absorption peak at 71S-730 nm and a 48-68 nm narrow emission spectrum with a surprisingly small, 18 nm Stokes shift at room temperature. The fluorescence lifetime of these PbS NPLs is 2 orders of magnitude shorter than the typical lifetime in OD colloidal PbS quantum dots, highlighting the advantageous properties of colloidal 2D nanostructures that combine strong transversal with weak lateral confinement

Facile Chemical Synthesis of Doped ZnO Nanocrystals Exploiting Oleic Acid

Zinc oxide nanocrystals (ZnO-NCs) doped with transition metal elements or rare earth elements can be probed for magnetic resonance imaging to be used as a molecular imaging technique for accurate diagnosis of various diseases. Herein, we use Mn as a candidate of transition metal elements and Gd as a presenter of rare earth elements. We report an easy and fast coprecipitation method exploiting oleic acid to synthesize spherical-shaped, small-sized doped ZnO-NCs. We show the improved colloidal stability of oleate-stabilized doped ZnO-NCs compared to the doped ZnO-NCs synthesized by conventional sol-gel synthesis method, i.e., without a stabilizing agent, especially for the Mn dopant. We also analyze their structural, morphological, optical, and magnetic properties. We are able to characterize the persistence of the crystalline properties (wurtzite structure) of ZnO in the doped structure and exclude the formation of undesired oxides by doping elements. Importantly, we determine the room-temperature ferromagnetism of the doped ZnO-NCs. This oleate-stabilized coprecipitation method can be subjected as a standard procedure to synthesize doped and also co-doped ZnO-NCs with any transition metal elements or rare earth elements. In the future, oleate-stabilized Gd/Mn-doped ZnO-NCs can be exploited as magnetic resonance imaging (MRI) contrast agents and possibly increase the signal intensity on T1-weighted images or reduce the signal intensity on T2-weighted images

Pushing Stoichiometries of Lithium-Rich Layered Oxides Beyond Their Limits

Lithium-rich layered oxides (LRLOs) are opening unexplored frontiers for high-capacity/high-voltage positive electrodes in Li-ion batteries (LIBs) to meet the challenges of green and safe transportation as well as cheap and sustainable stationary energy storage from renewable sources. LRLOs exploit the extra lithiation provided by the Li1.2TM0.8O2 stoichiometries (TM = a blend of transition metals with a moderate cobalt content) achievable by a layered structure to disclose specific capacities beyond 200-250 mA h g(-1) and working potentials in the 3.4-3.8 V range versus Li. Here, we demonstrate an innovative paradigm to extend the LRLO concept. We have balanced the substitution of cobalt in the transition-metal layer of the lattice with aluminum and lithium, pushing the composition of LRLO to unexplored stoichiometries, that is, Li-1.2(+x)(Mn,Ni,Co,AI)(0.8-x)O2-delta. The fine tuning of the composition of the metal blend results in an optimized layered material, that is, Li1.28Mn0.54Ni0.13Co0.02Al0.03O2-delta, with outstanding electrochemical performance in full LIBs, improved environmental benignity, and reduced manufacturing costs compared to the state-of-the-art

Nanozymes based on octahedral platinum nanocrystals with {111} surface facets: glucose oxidase mimicking activity in electrochemical sensors

The ability of shape-controlled octahedral Pt nanoparticles to act as nanozyme mimicking glucose oxidase enzyme is reported. Extended {111} particle surface facets coupled with a size comparable to natural enzymes and easy-to-remove citrate coating give high affinity for glucose, comparable to the enzyme as proven by the steady-state kinetics of glucose electrooxidation. The easy and thorough removal of the citrate coating, demonstrated by X-ray photoelectron spectroscopy analysis, allows a highly stable deposition of the nanozymes on the electrode. The glucose electrochemical detection (at -0.2 V vs SCE) shows a linear response between 0.36 and 17 mM with a limit of detection of 110 mu M. A good reproducibility has been achieved, with an average relative standard deviation (RSD) value of 9.1% (n = 3). Similarly, a low intra-sensor variability has been observed, with a RSD of 6.6% (n = 3). Moreover, the sensor shows a long-term stability with reproducible performances for at least 2 months (RSD: 7.8%). Tests in saliva samples show the applicability of Pt nanozymes to commercial systems for non-invasive monitoring of hyperglycemia in saliva, with recoveries ranging from 92 to 98%