2,937 research outputs found
Surface characterization
The biocompatibility of commercially pure titanium and its alloys is closely related to their surface properties, with both the composition of the protecting oxide film and the surface topography playing an important role. Surfaces of commercially pure titanium and of the two alloys Ti-6Al-7Nb and Ti-6Al-4V (wt %) have been investigated following three different pretreatments: polishing, nitric acid passivation and pickling in nitric acid-hydrogen fluoride. Nitric acid treatment is found to substantially reduce the concentration of surface contaminants present after polishing. The natural 4-6 nm thick oxide layer on commercially pure titanium is composed of titanium oxide in different oxidation states (TiO2, Ti2O3 and TiO), while for the alloys, aluminium and niobium or vanadium are additionally present in oxidized form (Al2O3, Nb2O5 or V-oxides). The concentrations of the alloying elements at the surface are shown to be strongly dependent on the pretreatment process. While pickling increases the surface roughness of both commercially pure titanium and the alloys, different mechanisms appear to be involved. In the case of commercially pure titanium, the dissolution rate depends on grain orientation, whereas in the case of the two alloys, selective α-phase dissolution and enrichment of the β-phase appears to occur. © 1999 Kluwer Academic Publisher
A new study of Mg(,n)Si angular distributions at = 3 - 5 MeV
The observation of Al gives us the proof of active nucleosynthesis in
the Milky Way. However the identification of the main producers of Al is
still a matter of debate. Many sites have been proposed, but our poor knowledge
of the nuclear processes involved introduces high uncertainties. In particular,
the limited accuracy on the Mg(,n)Si reaction cross
section has been identified as the main source of nuclear uncertainty in the
production of Al in C/Ne explosive burning in massive stars, which has
been suggested to be the main source of Al in the Galaxy. We studied
this reaction through neutron spectroscopy at the CN Van de Graaff accelerator
of the Legnaro National Laboratories. Thanks to this technique we are able to
discriminate the (,n) events from possible contamination arising from
parasitic reactions. In particular, we measured the neutron angular
distributions at 5 different beam energies (between 3 and 5 MeV) in the
\ang{17.5}-\ang{106} laboratory system angular range. The presented results
disagree with the assumptions introduced in the analysis of a previous
experiment.Comment: 9 pages, 9 figures - accepted by EPJ
Impact of Age on the Effectiveness and Safety of Insulin Glargine 300 U/mL: Results from the REALI European Pooled Data Analysis
Introduction: Patients aged ≥ 65 years continue to be underrepresented in clinical studies related to type 2 diabetes mellitus (T2DM). Accordingly, the REALI pooled analysis was performed to evaluate the effectiveness and safety of insulin glargine 300 U/mL (Gla-300) across different age subgroups, using data from 14 interventional and non-interventional studies. Methods: Pooled efficacy and safety data were collected from 8106 European patients with uncontrolled T2DM who were initiated on or switched to Gla-300 injected once daily for 24 weeks. Patients were categorised into five age subgroups: < 50 (N = 727), 50–59 (N = 2030), 60–69 (N = 3054), 70–79 (N = 1847) and ≥ 80 years (N = 448). Results: Mean baseline haemoglobin A1c (HbA1c) decreased linearly from the youngest (9.10%) to the oldest (8.46%) age subgroup. Following Gla-300 initiation, there were similar HbA1c reductions across age groups, with a least squares mean (95% confidence interval) change in HbA1c from baseline to week 24 of − 1.09% (− 1.18 to − 1.00), − 1.08% (− 1.14 to − 1.03), − 1.12% (− 1.17 to − 1.07), − 1.18% (− 1.24 to − 1.12) and − 1.11% (− 1.23 to − 0.99) in the < 50, 50–59, 60–69, 70–79 and ≥ 80 years subgroups, respectively. The incidences and event rates of reported hypoglycaemia were overall low. Compared to younger age subgroups, lower incidences of symptomatic hypoglycaemia occurring at any time of the day (5.9 vs. 7.6–9.4% for the younger subgroups) or during the night (0.5 vs. 1.6–2.5%) were recorded in patients aged ≥ 80 years. By contrast, the highest incidence of severe hypoglycaemia occurring any time of the day was reported in the subgroup aged ≥ 80 years (1.1 vs. 0.1–0.6% for the younger age subgroups). Conclusion: Gla-300 initiated in patients with uncontrolled T2DM provides glycaemic improvement with a favourable safety profile across a wide range of ages
Glycaemic Control with Insulin Glargine 300 U/mL in Individuals with Type 2 Diabetes and Chronic Kidney Disease: A REALI European Pooled Data Analysis
Introduction: Management of type 2 diabetes mellitus (T2DM) in patients with chronic kidney disease is complex. Using the REALI European pooled database, we determined the impact of baseline renal function on the effectiveness and safety of insulin glargine 300 U/mL (Gla-300) initiated in adults with inadequately controlled T2DM. Methods: Data from 1712 patients with available estimated glomerular filtration rate (eGFR) at baseline were pooled from six 24-week prospective studies. Patients who received once-daily subcutaneous injections of Gla-300 were classified into four renal function subgroups, according to baseline eGFR: ≥ 90 (N = 599), 60–89 (N = 786), 45–59 (N = 219), and 15–44 mL/min/1.73 m2 (N = 108). Results: Compared to those with baseline eGFR ≥ 60 mL/min/1.73 m2, patients with lower eGFR values tended to be older, had a longer T2DM duration, and were more likely to present diabetic complications. After 24 weeks of Gla-300 therapy, the least-squares mean (95% confidence interval) decrease in haemoglobin A1c (HbA1c) from baseline (− 1.14% [− 1.28 to − 1.00], − 1.21% [− 1.34 to − 1.08], − 1.19% [− 1.36 to − 1.01], and − 0.99% [− 1.22 to − 0.76]) and the proportion of patients achieving HbA1c < 7.5% (53.3%, 51.3%, 49.5%, and 51.5%) were comparable in the ≥ 90, 60–89, 45–59, and 15–44 mL/min/1.73 m2 subgroups, respectively. Although the incidence of hypoglycaemia was overall low, more patients in the eGFR 15–44 mL/min/1.73 m2 subgroup experienced hypoglycaemia at night or at any time of the day compared with higher eGFR subgroups. There were no notable differences between the renal function subgroups in the changes in Gla-300 daily dose and body weight from baseline to week 24. Conclusion: Although an eGFR of 15–44 mL/min/1.73 m2 was associated with a slightly increased risk of hypoglycaemia among patients with inadequately controlled T2DM, Gla-300 provided glycaemic improvement with an overall favourable safety profile regardless of baseline eGFR
Spin controlled atom-ion inelastic collisions
The control of the ultracold collisions between neutral atoms is an extensive
and successful field of study. The tools developed allow for ultracold chemical
reactions to be managed using magnetic fields, light fields and spin-state
manipulation of the colliding particles among other methods. The control of
chemical reactions in ultracold atom-ion collisions is a young and growing
field of research. Recently, the collision energy and the ion electronic state
were used to control atom-ion interactions. Here, we demonstrate
spin-controlled atom-ion inelastic processes. In our experiment, both
spin-exchange and charge-exchange reactions are controlled in an ultracold
Rb-Sr mixture by the atomic spin state. We prepare a cloud of atoms in a
single hyperfine spin-state. Spin-exchange collisions between atoms and ion
subsequently polarize the ion spin. Electron transfer is only allowed for
(RbSr) colliding in the singlet manifold. Initializing the atoms in various
spin states affects the overlap of the collision wavefunction with the singlet
molecular manifold and therefore also the reaction rate. We experimentally show
that by preparing the atoms in different spin states one can vary the
charge-exchange rate in agreement with theoretical predictions
On FPL configurations with four sets of nested arches
The problem of counting the number of Fully Packed Loop (FPL) configurations
with four sets of a,b,c,d nested arches is addressed. It is shown that it may
be expressed as the problem of enumeration of tilings of a domain of the
triangular lattice with a conic singularity. After reexpression in terms of
non-intersecting lines, the Lindstr\"om-Gessel-Viennot theorem leads to a
formula as a sum of determinants. This is made quite explicit when
min(a,b,c,d)=1 or 2. We also find a compact determinant formula which generates
the numbers of configurations with b=d.Comment: 22 pages, TeX, 16 figures; a new formula for a generating function
adde
Characterization of Large Volume 3.5 x 8 inches LaBr3:Ce Detectors
The properties of large volume cylindrical 3.5 x 8 inches (89 mm x 203 mm)
LaBr3:Ce scintillation detectors coupled to the Hamamatsu R10233-100SEL
photo-multiplier tube were investigated. These crystals are among the largest
ones ever produced and still need to be fully characterized to determine how
these detectors can be utilized and in which applications. We tested the
detectors using monochromatic gamma-ray sources and in-beam reactions producing
gamma rays up to 22.6 MeV; we acquired PMT signal pulses and calculated
detector energy resolution and response linearity as a function of gamma-ray
energy. Two different voltage dividers were coupled to the Hamamatsu
R10233-100SEL PMT: the Hamamatsu E1198-26, based on straightforward resistive
network design, and the LABRVD, specifically designed for our large volume
LaBr3:Ce scintillation detectors, which also includes active semiconductor
devices. Because of the extremely high light yield of LaBr3:Ce crystals we
observed that, depending on the choice of PMT, voltage divider and applied
voltage, some significant deviation from the ideally proportional response of
the detector and some pulse shape deformation appear. In addition, crystal
non-homogeneities and PMT gain drifts affect the (measured) energy resolution
especially in case of high-energy gamma rays. We also measured the time
resolution of detectors with different sizes (from 1x1 inches up to 3.5x8
inches), correlating the results with both the intrinsic properties of PMTs and
GEANT simulations of the scintillation light collection process. The detector
absolute full energy efficiency was measured and simulated up to gamma-rays of
30 Me
Rationale and methodology for a European pooled analysis of postmarketing interventional and observational studies of insulin glargine 300 U/mL in diabetes: Protocol of REALI project
Introduction Type 2 diabetes mellitus (T2DM) is a common and heterogeneous disease. Using advanced analytic approaches to explore real-world data may identify different disease characteristics, responses to treatment and progression patterns. Insulin glargine 300 units/mL (Gla-300) is a second-generation basal insulin analogue with preserved glucose-lowering efficacy but reduced risk of hypoglycaemia. The purpose of the REALI pooled analysis described in this paper is to advance the understanding of the effectiveness and real-world safety of Gla-300 based on a large European patient database of postmarketing interventional and observational studies. Methods and analysis In the current round of pooling, REALI will include data from up to 10 000 subjects with diabetes mellitus (mostly T2DM) from 20 European countries. Outcomes of interest include change from baseline to week 24 in haemoglobin A 1c, fasting plasma glucose, self-measured plasma glucose, body weight, insulin dose, incidence and rate of any-time-of-the-day and nocturnal hypoglycaemia. The data pool is being investigated using two complementary methodologies: a conventional descriptive, univariate and multivariable prognostic analysis; and a data-mining approach using subgroup discovery to identify phenotypic clusters of patients who are highly associated with the outcome of interest. By mid-2019, deidentified data of 7584 patients were included in the REALI database, with a further expected increase in patient number in 2020 as a result of pooling additional studies. Ethics and dissemination The proposed study does not involve collection of primary data. Moreover, all individual study protocols were approved by independent local ethics committees, and all study participants provided written informed consent. Furthermore, patient data is deidentified before inclusion in the REALI database. Hence, there is no requirement for ethical approval. Results will be disseminated via peer-reviewed publications and presentations at international congresses as data are analysed
Glycaemic Control with Insulin Glargine 300 U/mL in Individuals with Type 2 Diabetes and Chronic Kidney Disease: A REALI European Pooled Data Analysis
INTRODUCTION:
Management of type 2 diabetes mellitus (T2DM) in patients with chronic kidney disease is complex. Using the REALI European pooled database, we determined the impact of baseline renal function on the effectiveness and safety of insulin glargine 300 U/mL (Gla-300) initiated in adults with inadequately controlled T2DM.
METHODS: Data from 1712 patients with available estimated glomerular filtration rate (eGFR) at baseline were pooled from six 24-week prospective studies. Patients who received once-daily subcutaneous injections of Gla-300 were classified into four renal function subgroups, according to baseline eGFR: ≥ 90 (N = 599), 60–89 (N = 786), 45–59 (N = 219), and 15–44 mL/min/1.73 m2 (N = 108).
RESULTS: Compared to those with baseline eGFR ≥ 60 mL/min/1.73 m2, patients with lower eGFR values tended to be older, had a longer T2DM duration, and were more likely to present diabetic complications. After 24 weeks of Gla-300 therapy, the least-squares mean (95% confidence interval) decrease in haemoglobin A1c (HbA1c) from baseline (− 1.14% [− 1.28 to − 1.00], − 1.21% [− 1.34 to − 1.08], − 1.19% [− 1.36 to − 1.01], and − 0.99% [− 1.22 to − 0.76]) and the proportion of patients achieving HbA1c < 7.5% (53.3%, 51.3%, 49.5%, and 51.5%) were comparable in the ≥ 90, 60–89, 45–59, and 15–44 mL/min/1.73 m2 subgroups, respectively. Although the incidence of hypoglycaemia was overall low, more patients in the eGFR 15–44 mL/min/1.73 m2 subgroup experienced hypoglycaemia at night or at any time of the day compared with higher eGFR subgroups. There were no notable differences between the renal function subgroups in the changes in Gla-300 daily dose and body weight from baseline to week 24.
CONCLUSION:
Although an eGFR of 15–44 mL/min/1.73 m2 was associated with a slightly increased risk of hypoglycaemia among patients with inadequately controlled T2DM, Gla-300 provided glycaemic improvement with an overall favourable safety profile regardless of baseline eGFR
Does Gender Influence the Effectiveness and Safety of Insulin Glargine 300 U/ml in Patients with Uncontrolled Type 2 Diabetes? Results from the REALI European Pooled Analysis
Introduction: Gender differences in risk factors and treatment outcomes for type 2 diabetes mellitus (T2DM) may exist. We used the REALI European database to investigate whether there were gender-specific differences in baseline characteristics and clinical outcomes among patients with inadequately controlled T2DM initiated on insulin glargine 300 U/ml (Gla-300). // Methods: Data were pooled from 14 multicentre, prospective, interventional and non-interventional studies. Impact of gender on glycaemic control, insulin dose, body weight and hypoglycaemia was evaluated after 12 and 24 weeks of Gla-300 treatment. // Results: Women (N = 3857) were older than men (N = 4376) (median age, 65.0 versus 63.0 years), with greater mean body mass index (32.5 versus 31.6 kg/m2) and lower median estimated glomerular filtration rate (77.5 versus 84.0 ml/min/1.73 m2). Peripheral arterial disease and a history of myocardial infarction were more frequent in men (20.1% versus 11.7% and 12.0% versus 5.8%, respectively). At baseline, mean haemoglobin A1c (HbA1c) was 8.74% in men and 8.79% in women. Least square (LS) mean (95% CI) reduction in HbA1c from baseline to week 24 was − 1.17% (− 1.21 to − 1.13) in men and − 1.07% (− 1.11 to − 1.02) in women, resulting in a LS mean difference of − 0.10% (− 0.15 to − 0.05; p < 0.0001). At 24 weeks, 21.6% of women and 27.2% of men achieved target HbA1c of < 7.0% (p < 0.001; chi-square). Reported incidence for symptomatic (8.5% versus 8.7%) and severe (0.3% versus 0.5%) any-time-of-the-day or symptomatic (2.4% versus 1.8%) and severe (0.1% versus 0.2%) nocturnal hypoglycaemia was overall low and comparable between men and women. Changes in daily Gla-300 dose and body weight were also similar. // Conclusion: Despite some gender differences in baseline characteristics, Gla-300 treatment improved glycaemic control, with overall low hypoglycaemia incidences in both men and women. However, women had statistically significantly lower HbA1c reductions than men, although these differences were clinically modest
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