27 research outputs found
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part I. Primary batteries
No full textSome non-stoichiometric Mo oxides have been tested as cathodes for primary Li cells. Their performance has been evaluated as a function of current density, electrolyte, temperature, cathode porosity and formulation. Specific capacities exceeding 0.4·Ah g−1 could be reached at low rates. As found with MoO3, these oxides give rise to the formation of ternary phases of the type LimyMomO3m−1. Li+ insertion in the lattices allows structure retention for Li/Mo ratios lower than 0.7–0.8, whereas higher Li+ contents result in the appearance of new phases
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part III. cells based on Mo18O52
No full textThe non-stoichiometric Mo18O52 oxide, based on the MoO3 structure, was tested as a cathode material in both primary and secondary Li cells. It may intercalate reversibly in its layered structure up to 1.2 Li/Mo (at 0.5–1.0 mA cm−2), so forming ternary phases.
In the solid matrix Li+ ion diffusion is relatively fast (D≈10−9 cm2 s−1) and gives rise to a structure in which Li+ is tetrahedrally coordinated by oxygen. This oxide shows a high rate capability and can also act as a cathode material for secondary batteries in the low-rate range. The resemblance to the parent oxide MoO3 is obviously marked but differences were found with regard to the effect of additives and to the recharge efficiency, due to some structural difference
Nonaqueous Batteries with BiF3 Cathodes
No full textLi cells based on BiF3 cathodes have been tested. In particular, the effect ofcathode formulation and compacting pressure, nature of the solution, temperature,and current density have been evaluated. Through x-ray analysis, cyclicvoltammetry, and coulometric analysis it was possible to ascertain that BiF3is reduced to Bi and then to Li3Bi. During the first reduction process, ternaryphases of the LixBiF3 type are probably formed. Li/BiF3 cells can give practicalenergy densities in excess of 200 W-hr/kg at the rate of 0.5 mA/cm
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part II. Secondary batteries
No full textMo4O11, Mo8O23 and Mo9O26 have been examined as cathodes for secondary lithium cells. These oxides can form ternary phases from which Li+ can be almost quantitatively recovered on charge, for limited e/Mo values (e.g. 0.8 for Mo8O23). Higher values of e/Mo make the reduction process irreversible due to the destruction of the original lattices. Cyclic voltammetry experiments have shown that these oxides can maintain their reversible behaviour for many cycles, provided the cathodic scanning is limited. Cycling of prismatic Li/Mo8O23 cells has confirmed that this oxide can behave reversibly with good voltage retention even at discharge depths near the limiting valu
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part IV. Factors influencing the performance of Li/Mo8O23 batteries
No full textMo8O23 was further investigated as a cathode material suitable for secondary Li batteries. Within the channels present in the basic slabs of its ReO3-type structure, it can accept up to 1.0 Li+/Mo through an octahedrical coordination of Li+ by O. The oxide performance in primary cells was seen to be largely dependent on cathode formulation and solution volume. As a secondary cathode it give single-cycle recharge efficiencies as high as 95% at 1.0 mA cm−2 and 0.5 e/Mo. Prolonged cycling in button cells at 1.0 and 2.0 mA cm−2 also gives satisfactory results. X-ray analysis shows that after cycling the structure does not suffer from significant distortion
Genetic analyses of HIV-1 pol sequences from Zimbabwean patients
No full textThis study analysed the sequence of HIV-1 pol gene derived from Zimbabwean infected patients. Sequence analysis, performed on 8 samples, revealed that sequences were classified as subtype C (n=5), subtype B (n=2) and CRF01-AE (n=1). Two patients, treated with a therapeutic regimen containing NRTI/NNRTI, harboured drug resistance mutations in HIV-1 DNA. Phylogenetic analysis performed on subtype C sequences showed that our strains were aggregated in different clusters depending on the country of origin
Reactivation of Toxoplasma gondii in HIV-infected population from rural area of Zimbabwe
No full textComparison of clinical characteristics of tuberculosis between two age groups at an Italian Tertiary Hospital
No full textDifferences in clinical characteristics and outcome between elderly (>60 years) and younger (18–59 years) tuberculosis (TB) patients were retrospectively evaluated. Alcohol abuse, radiological evidence of cavitation, and cough at presentation were more frequent among younger patients. Older patients were more likely to have comorbidities, disseminated TB, longer duration of symptoms and higher TB-related mortality (19 vs 0%). Very old patients (≥80 years) showed increased liver toxicity and hospital acquired infections compared to patients aged 60–79 year
Clinical characteristics, management and health related quality of life in young to middle age adults with COVID-19
No full textBackground: The outbreak of COVID-19 has rapidly spread to Italy, including Pesaro-Urbino province. Data on young to middle age adults with COVID-19 are lacking. We report the characteristics, management and health-related quality of life (HRQoL) in patients with COVID-19 aging ≤50 years. Methods: A retrospective analysis was performed in all patients ≤50 years with a confirmed diagnosis of COVID-19 admitted to Emergency department (ED) of San Salvatore Hospital in Pesaro from February 28th to April 8th, 2020. Data were collected from electronical medical records. HRQoL was investigated after 1 month from hospital discharge using the SF-36 questionnaire. Outcomes were evaluated between hospitalized and not hospitalized patients. Results: Among 673 patients admitted to the ED and diagnosed with COVID-19, 104 (15%) were ≤ 50 years old: 74% were discharged at home within 48 h, 26% were hospitalized. Fever occurred in 90% of the cases followed by cough (56%) and dyspnoea (34%). The most frequent coexisting conditions were hypertension (11%), thyroid dysfunction (8%) and neurological and/or mental disorders [NMDs] (6%). Mean BMI was 27. Hypokalaemia and NMDs were significantly more common in patients who underwent mechanical ventilation. Regardless of hospitalization, there was an impairment in both the physical and mental functioning. Conclusions: Overweight and hypertension are frequent conditions in young to middle age adults with COVID-19. Hypokalaemia and NMDs are commonly associated with progressive disease. A significant impact on HRQoL in the early stage of post-discharge is common in this population
Maintaining gait stability during dual walking task: effects of age and neurological disorders
No full textBACKGROUND: Dual task paradigm is a common mechanism of daily life, and it is often used for investigating the effect on cognitive processing of motor behavior. AIM: In the present study we investigate the dual task interference during walking on upright gait stability. DESIGN: Cross-sectional study. SETTING: Inpatient neurorehabilitation unit and children neurorehabilitation unit. POPULATION: Eighty-five subjects were enrolled, divided into five groups: healthy young, healthy elderly, children with typical development, children with cerebral palsy and adults with stroke in subacute phase. METHODS: All subjects had to walk through a pathway during which they had to hear a sound, turn the head to watch a number and verbalize it. Subjects wore an accelerometer on their lumbar spine to measure upright gait stability have been assessed by means of the Root Mean Square (RMS) of the trunk acceleration. RESULTS: All subjects showed a reduced speed when performing a dual task with respect to single task. This reduction was significantly different among groups (F(4,81) =12.253, P<0.001, effect size 0.377). The RMS appeared to be increased along the latero-lateral axis, and reduced along the anterio-posterior and the cranio-caudal axes during the dual task walking. CONCLUSIONS: These accelerations were significantly related to the changes in speed that were managed in a different way in subjects affected by cerebral palsy and stroke. CLINICAL REHABILITATION IMPACT: The information obtained in this study may be used to support specific rehabilitation techniques in subjects with poor balance ability
