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In this paper, we calculate the diagonal contributions W(R, s = 0) of the imaginary part of the microsopic optical potential at negatives energies, where W(R, s) = Σlj(2j+1)/4π Im∆Σlj(r, r′, ω), with R = 1/2.(r + r′) corresponding to the radius and shape of Im∆Σ, and s = r - r′. To do it, the microscopic optical potential has been calculated by using the nuclear structure approach which is based on the Green function method. The coupling between the particle and collective phonon has been performed to calculate the dynamic part of the optical potential. It has been found that the imaginary part at negative energies is very small as expected. The calculated W(R, 0) is maximum on the surface and deacreases to zero in the interior.

We present a combined experimental and theoretical study of surface-related magnetic states in TiO 2. Our experiments on nano-sized thin films of pure TiO 2 have suggested that the observed room-temperature magnetism originates from defects, in particular, from the surface of thin films as well as from point defects, such as oxygen vacancies located mainly at the surface. Clarifying this phenomenon is very important for harnessing magnetic properties of pristine TiO 2 films in future spintronic applications but a detailed experimental investigation is very demanding. Therefore, quantum-mechanical density functional theory calculations were performed for (i) bulk anatase TiO 2 , (ii) bulk-like TiO 2 -terminated vacancy-free (001) surfaces, (iii) vacancy-containing TiO-terminated (001) surfaces, (iv) TiO 0.75 -terminated (001) surfaces with additional 25% surface oxygen vacancies, as well as (v) oxygen-terminated (001)-surfaces. Our fixed-spin-moment calculations identified both the bulk and the bulk-like terminated vacancy-free TiO 2 -terminated (001) surfaces as non-magnetic. In contrast, oxygen vacancies in the case of TiO-terminated and TiO 0.75 -terminated (001) surfaces lead to ferromagnetic and rather complex ferrimagnetic states, respectively. The spin-polarized atoms are the Ti atoms (due to the d -states) located in the surface and sub-surface atomic planes. Last, the O-terminated surfaces are also magnetic due to the surface and sub-surface oxygen atoms and sub-surface Ti atoms (but their surface energy is high). [ABSTRACT FROM AUTHOR]

Introduction: Adherence to dual antiplatelet therapy (DAPT) is critical after drug-eluting stent(DES) placement. We aimed to assess patient’s knowledge, rates of DAPT adherence, trends in DAPT use over time, and patient‐level factors associated with nonadherence in the patient with acute coronary syndrome (ACS). Methods: ACS patients who received one or more DES between May and September 2018from two hospitals in Vietnam and used DAPT after stent placement were eligible for a direct interview to assess patient’s knowledge on disease and DAPT. Telephone interviews were conducted one, three, and six months following discharge. Nonadherence was defined as premature discontinuation of DAPT. Factors related to nonadherent patients were analyzed using the chi-square test. Results: Of the 200 patients identified, 154 (77%) participated. Of the ten questions related to knowledge, the mean score of correct answers was 8.2 ± 2.3, and 71.7% had good knowledge.Adherence to DAPT was high at one month (94.2%) but declined by three months (44.2%) and then by six months (46.8%). Aspirin adherence was 99.3%-100% throughout. Three factors associated with nonadherence of DAPT following DES placement by six months included: rural location, linactive occupation, and inadequate knowledge on disease and DAPT (p

AbstractWe choose to examine founder succession as a benchmark of the entrepreneurial transition phenomenon and employ bibliometric analyses of 151 articles on founder succession research published in peer-reviewed journals from 1997 to 2021 to provide a systematic assessment of the existing literature. Keyword co-occurrence analyses map out important topics and hot trends in this research. Co-authorship network analyses clarify the community of renowned scholars working on this literature stream and their co-authorship preferences. Their citation patterns and various bibliometric parameters clearly exhibit the emergence of founder succession as a potential literature. Finally, discussion of findings and recommendations for future research are discussed.

Experimentally it is shown that without any oxygen manipulation for TiO2, a strong room temperature ferromagnetism could be expected only in ultra-thin films, with the ideal thickness below 100 nm. Both bulks and nano-powders of TiO2 are diamagnetic, indicating that the surface and its nano-sublayers play very important roles in tailoring the magnetic properties in this type of compound. To shed a new light on the defect-related magnetism in the typical case of anatase TiO2 surfaces, we have performed a series of quantum-mechanical calculations for TiO2 slabs containing Ti or O vacancies in different distances from the (001) surface. The lowest formation energies were obtained for the Ti vacancies in the first sub-surface layer and the O vacancies within the surface. The computed magnetic states reflect complicated structural relaxations of atoms influenced by both the surface and vacant atomic positions. O atoms cannot contribute much to magnetic moment when Ti vacancies are isolated and far from the surface. Ti vacancies in TiO2 are only metastable. The formation energy of Ti interstitials is lower than for Ti vacancies since high-temperature annealing, especially with a lot of O2 available that would fill up O-related defects, and as a result, eliminate most of Ti vacancies. Lower temperatures, less O2, and shorter exposure times may enable not only partial elimination of Ti vacancies but also can facilitate their diffusion into different states of aggregations. In the ferromagnetic films (i.e. thin films below 100 nm), it looks like that the O atoms are located closer to the Ti vacancies. [ABSTRACT FROM AUTHOR]

Orange‐red‐emitting Eu3+‐doped Ca9Gd(PO4)7 phosphors have been obtained by a sol‐gel technique. These phosphors, excited by UV (270 nm) and near UV light (394 nm), emit orange‐red light in the range of 580–710 nm. The Ca9Gd(PO4)7:7 mol% Eu3+ phosphor annealed at 1100 °C shows the highest PL intensity. Judd‐Ofelt analysis reveals that the neighbor surroundings of Eu3+ ions are asymmetric, and the lowest asymmetry value is found at the dopant ratio of 7 mol%. The optimal phosphor excited by the wavelength of 394 nm displays an excellent thermal stability (∼76.4 % at 160 °C) with an activation energy of 0.163 eV. The corresponding CIE chromaticity coordinates (x; y) and color purity are calculated to be (0.5849; 0.3635) and 84.6 %, respectively. The quantum efficiency values of the Ca9Gd(PO4)7:Eu3+ phosphors coated on UV and near‐UV chips are 87.4 % and 5.1 %, respectively. It is the first time that the QE values of Ca9Gd(PO4)7:Eu3+‐based red and blue‐emitting LEDs are reported. [ABSTRACT FROM AUTHOR]

Background: An endotracheal tube cuff pressure between 20 and 30 cmH2O is recommended to prevent ventilator-associated respiratory infection (VARI). We aimed to evaluate whether continuous cuff pressure control (CPC) was associated with reduced VARI incidence compared with intermittent CPC., Methods: We conducted a multicenter open-label randomized controlled trial in intensive care unit (ICU) patients within 24 hours of intubation in Vietnam. Patients were randomly assigned 1:1 to receive either continuous CPC using an automated electronic device or intermittent CPC using a manually hand-held manometer. The primary endpoint was the occurrence of VARI, evaluated by an independent reviewer blinded to the CPC allocation., Results: We randomized 600 patients; 597 received the intervention or control and were included in the intention to treat analysis. Compared with intermittent CPC, continuous CPC did not reduce the proportion of patients with at least one episode of VARI (74/296 [25%] vs 69/301 [23%]; odds ratio [OR] 1.13; 95% confidence interval [CI] .77-1.67]. There were no significant differences between continuous and intermittent CPC concerning the proportion of microbiologically confirmed VARI (OR 1.40; 95% CI .94-2.10), the proportion of intubated days without antimicrobials (relative proportion [RP] 0.99; 95% CI .87-1.12), rate of ICU discharge (cause-specific hazard ratio [HR] 0.95; 95% CI .78-1.16), cost of ICU stay (difference in transformed mean [DTM] 0.02; 95% CI -.05 to .08], cost of ICU antimicrobials (DTM 0.02; 95% CI -.25 to .28), cost of hospital stay (DTM 0.02; 95% CI -.04 to .08), and ICU mortality risk (OR 0.96; 95% CI .67-1.38)., Conclusions: Maintaining CPC through an automated electronic device did not reduce VARI incidence., Clinical Trial Registration: NCT02966392., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)