The paper discusses the preparation of multicomponent thin films of Cu-Ti composite with desired elemental composition using the pulsed magnetron co-sputtering technology. The technological goal ...described in the paper was deposition the Cu-Ti composite with elemental ratio of about 50/50 at%, which is close to the eutectic point from the Cu-Ti alloy system. A large difference in the sputtering yield (about seven-fold) of Cu and Ti metals was challenging, because of the features of used power supplies. Desired concentrations of the Ti and Cu elements were obtained as a result of application of multimagnetron sputtering system, where magnetrons were equipped with the Ti or Cu targets. Additionally, pulse power supply was used together with the pulse width modulation controller. Moreover, the article presents investigations of structural and mechanical properties of deposited Cu, Ti and Cu-Ti films with elemental composition of ca. 50/50 at.%. It was found that the two component Cu0.5Ti0.5 thin films were composed of Cu4Ti3 nanocrystallites built-in an amorphous matrix. As compared to the pure Cu and Ti thin films, the prepared composite exhibited improved hardness and better elasticity reflected in lower values of the Young's modulus. The results of nanoindentation investigations showed that the Cu0.5Ti0.5 composite thin film was characterized by the hardness of 7.59 GPa.
•A multi-magnetron co-sputtering system was scaled on the Cu-Ti case study.•The Cu-Ti material were selected due to the large difference in the sputtering yield.•A desired chemical composition of ca. 50/50 at.% of Cu/Ti thin film was obtained.•The Cu0.5Ti0.5 thin films composed from Cu4Ti3 nanocrystallites built in an amorphous matrix.•The Cu0.5Ti0.5 composite, as compared to Cu and Ti thin films, showed improved hardness and better elasticity.
An extensive clinical development program (comprising two phase 2 and five phase 3 trials) has demonstrated the efficacy and safety of ceftazidime-avibactam in the treatment of adults with ...complicated intra-abdominal infection (cIAI), complicated urinary tract infection (cUTI), and hospital-acquired pneumonia (HAP), including ventilator-associated pneumonia (VAP). During the phase 3 clinical program, updated population pharmacokinetic (PK) modeling and Monte Carlo simulations using clinical PK data supported modified ceftazidime-avibactam dosage adjustments for patients with moderate or severe renal impairment (comprising a 50% increase in total daily dose compared with the original dosage adjustments) to reduce the risk of subtherapeutic drug exposures in the event of rapidly improving renal function. The modified dosage adjustments were included in the ceftazidime-avibactam labeling information at the time of initial approval and were subsequently evaluated in the final phase 3 trial (in patients with HAP, including VAP), providing supportive data for the approved U.S. and European ceftazidime-avibactam dosage regimens across renal function categories. This review describes the analyses supporting the ceftazidime-avibactam dosage adjustments for renal impairment and discusses the wider implications and benefits of using modeling and simulation to support dosage regimen optimization based on emerging clinical evidence.
Hydrogen is an efficient source of clean and environmentally friendly energy. However, because it is explosive at concentrations higher than 4%, safety issues are a great concern. As its applications ...are extended, the need for the production of reliable monitoring systems is urgent. In this work, mixed copper-titanium oxide ((CuTi)Ox) thin films with various copper concentrations (0-100 at.%), deposited by magnetron sputtering and annealed at 473 K, were investigated as a prospective hydrogen gas sensing material. Scanning electron microscopy was applied to determine the morphology of the thin films. Their structure and chemical composition were investigated by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The prepared films were nanocrystalline mixtures of metallic copper, cuprous oxide, and titanium anatase in the bulk, whereas at the surface only cupric oxide was found. In comparison to the literature, the (CuTi)Ox thin films already showed a sensor response to hydrogen at a relatively low operating temperature of 473 K without using any extra catalyst. The best sensor response and sensitivity to hydrogen gas were found in the mixed copper-titanium oxides containing similar atomic concentrations of both metals, i.e., 41/59 and 56/44 of Cu/Ti. Most probably, this effect is related to their similar morphology and to the simultaneous presence of Cu and Cu
O crystals in these mixed oxide films. In particular, the studies of surface oxidation state revealed that it was the same for all annealed films and consisted only of CuO. However, in view of their crystalline structure, they consisted of Cu and Cu
O nanocrystals in the thin film volume.
Bina Darma University is an educational institution that has the obligation to provide leave rights for its employees and lecturers. For the process of implementing, managing, calculating, replacing ...leave will be the task of the Directorate of Human Resources (DSDM). DSDM has provisions regarding rules for granting leave or permission not to work. Employees and lecturers who will apply for leave must submit the application in writing using the leave application form. The application of this manual method has several weaknesses, namely lack of efficiency, takes a long time because it has not been computerized. Also less effective in the work process, because of the many uses of paper so difficult to control the approval of the application especially if the applicant and the approver is not in the workplace location. Based on these conditions a system is needed to assist in the regulation of leave and permit applications for employees and lecturers. The method used in developing this system is the Rapid Application Development (RAD) method. There are three phases in RAD namely planning, design workshops and implementation.
•CuTi-containing catalyst derived from hydrotalcite-like used for NOx removal.•Cu can be categorized into surface and bulk species of the CuTi-containing catalyst.•Surface Cu is active site, while ...bulk Cu possesses adsorption property.•Lewis acid sites actively contribute to the catalytic performance.•Nitrates, acetate and formate are evidenced as key intermediates for NOx removal.
A series of hydrotalcite-based CuxTi1 (x=2, 3, 4, 5)-mixed oxide catalysts have been synthesized by homogeneous precipitation and tested in the selective catalytic reduction (SCR) of NO by C3H6 in the presence of excess oxygen. Cu atoms can be categorized into surface and bulk species. The surface Cu species are the active sites while the bulk Cu species possess adsorption property for nitrogen species, and such bulk Cu species varies from CuxTiyOz to CuO with increasing Cu content. The Cu3Ti1 catalyst with the highest amount of surface copper and Lewis acid sites exhibits the best catalytic performance due to its improved electrophilicity of CuxTiyOz, which enhance the adsorption capability of nitrogen species. In situ infrared characterization revealed that nitrates in terms of bridging, bidentate and chelating species are reactive toward acetate and formate, and they are the key intermediates produced during the SCR of NO.
In this communication, the synthesis of the Ca
3
CuTi
4
O
12
(CCTO) ceramic by a conventional solid-state reaction method is reported. The XRD analysis confirms an orthorhombic structure with average ...crystallite size and lattice strain are about 96.5 nm and 0.116% respectively. Field emission scanning electron microscope (FESEM) analysis confirms both weight and atomic percentage of all constituent elements and agglomeration rate of grains (D
SEM
/D
SC
= 7.4); which may be a possible reason for the observed elevated dielectric constant. No trace of phase transition is observed from the Raman lines; so, the observed giant dielectric constant may not be related to the displacement of Ti ions. The energy bandgap is about 3.72 eV, which may suitable for photovoltaic applications. The semiconducting nature is confirmed from the both Nyquist and Cole-Cole plots. Thermistor constant (β), sensitivity factor (α), and stability factor of the sample were calculated; which confirms the characteristics of the NTC thermistor.
In a recent multicenter population pharmacokinetic study of ciprofloxacin administered to children suffering from complicated urinary tract infection (cUTI), the apparent volume of distribution (V) ...and total plasma clearance (CL) were decreased by 83.6% and 41.5% respectively, compared to healthy children. To understand these differences, a physiologically-based pharmacokinetic model (PBPK) for ciprofloxacin was developed for cUTI children. First, a PBPK model in adults was developed, modified incorporating age-dependent functions and evaluated with paediatric data generated from a published model in healthy children. Then, the model was then adapted to a cUTI paediatric population according to the degree of renal impairment (KF) affecting renal clearance (CLRenal,) and CYP1A2 clearance (CLCYP1A2). Serum and urine samples obtained from 22 cUTI children were used for model evaluation. Lastly, a parameter sensitivity analysis identified the most influential parameters on V and CL. The PBPK model predicted the ciprofloxacin exposure in adults and children, capturing age-related pharmacokinetic changes. Plasma concentrations and fraction excreted unchanged in urine (fe) predictions improved in paediatric cUTI patients once CLrenal and CLCYP1A2 were corrected by KF. The presented PBPK model for ciprofloxacin demonstrates its adequacy to simulate different dosing scenarios to obtain PK predictions in a healthy population from 3 months old onwards. Model adaptation of CLRenal and CLCYP1A2 according to KF explained partially the differences seen in the plasma drug concentrations and fe vs time profiles between healthy and cUTI children. Nevertheless, it is necessary to further investigate the disease-related changes in cUTI to improve model predictions.
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Urinary tract infections (UTIs) are one of the leading causes of multidrug-resistance (MDR) spread and infection-related deaths.
is by far the main causative agent. We conducted a prospective study ...on complicated urinary tract infections (cUTIs) i) to monitor the high-risk clones that could be compromising the therapeutic management and ii) to compare the cUTI etiology with uncomplicated infections (uUTIs) occurring in the same period and health area.
154 non-duplicated
recovered from cUTIs in 2020 at the Hospital Universitario Central de Asturias (Spain) constituted the study collection.
Most cUTI isolates belonged to phylogroup B2 (72.1%) and met the uropathogenic (UPEC) status (69.5%) (≥3 of
,
,
, and
genes). MDR was exhibited by 35.7% of the isolates, similarly to data observed in the uUTI collection. A significant difference observed in cUTI was the higher level of fluoroquinolone resistance (FQR) (47.4%), where the pandemic clonal groups B2-CC131 and B2-ST1193 (CH14-64) comprised 28% of the 154
, representing 52.1% of the FQR isolates. Other prevalent FQR clones were D-ST69 (CH35-27), D-ST405 (CH37-27), and B2-ST429 (CH40-20) (three isolates each). We uncovered an increased genetic and genomic diversity of the CC131: 10 different virotypes, 8 clonotypes (CH), and 2 STs. The presence of
was determined in 12 (7.8%) isolates (all CC131), which showed 10 different core genome (cg)STs and 2
H types (
H30 and
H602) but the same set of chromosomal mutations conferring FQR (
p.S83L,
p.D87N,
p.S80I,
p.E84V, and
p.I529L). In addition, the plasmidome analysis revealed 10 different IncF formulae in CC131 genomes.
We proved here that non-lactose fermenting screening, together with the detection of O25b (
O25b), H4 (
), and H5 (
) genes, and phylogroup and clonotyping assignation, is a reasonable approach that can be easily implemented for the surveillance of emerging high-risk clones associated with FQR spread in cUTIs, such as the uncommonly reported O25b:H4-B2-ST9126-CC131 (CH1267-30). Since
CC131 and ST1193 are also involved in the community uUTIs of this health area, interventions to eradicate these MDR clones, along with surveillance for other emerging ones, are essential for antibiotic use optimization programs.
Molecular dynamic simulation was used to study mechanism of self-propagating waves of explosive crystallization (devitrification) in the CuTi metallic glass. Processes in thin rectangular samples ...composed of one to two million atoms were simulated and compared with experimental data. It was shown that the nucleation of primary crystalline clusters occurs homogeneously due to spontaneous fluctuations of atomic structure; the clusters not <50–100 atoms (~ 8–10 nm in diameter) have good chance to grow into steady crystalline grain. Self-propagating front of crystallization can be initiated locally from one end of the glassy sample; it propagates across the whole sample accompanied by a thermal wave, due to the exothermic effect of devitrification. Temperature rises in the front of this wave from 500 to 550 K up to 665–714 K; the thickness of preheated zone is about 20 nm, the thickness of amorphous-to-crystalline transition zone ~ 1 nm, the propagating velocity is 40 m/s. The uniform heating of the whole sample above 600 K leads to spontaneous nucleation and growth of many crystalline grains, which cause a self-heating of the sample similar to a thermal explosion.
•We apply molecular dynamic simulation to study explosive devitrification of CuTi.•Primary crystalline clusters nucleate homogeneously, critical size 50–100 atoms.•Devitrification (crystallization) front self-propagates accompanied by thermal wave.•Uniform pre-heating results in thermal-explosive self-heating crystallization.•Results of MDS confirm existence of explosive crystallization in metallic glasses.
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