A Modified Super-Efficiency in the Range Directional Model

The range directional model (RDM) relaxes the assumption of non-negativity of inputs and outputs in the conventional data envelopment analysis (DEA) with the aim of evaluating the efficiency of a decision-making unit (DMU) when some data are negative. Although the concept of super-efficiency in the RDM contributes to enhancing discriminatory power, the formulated model may lead to the infeasibility problem for some efficient DMUs. In this paper, we modify the super-efficiency RDM (SRDM) model to overcome the infeasibility problem occurring in such cases. Our method leads to a complete ranking of the DMUs with negative data for yielding valuable insights that aid decision makers to better understand the findings from a performance evaluation process. The contribution of this paper is fivefold: (1) we detect the source of infeasibility problems of SRDM in the presence of negative data, (2) the proposed model in this study yields the SRDM measures regardless of feasibility or infeasibility of the model, (3) when feasibility occurs, the modified SRDM model results in the scores that are the same as the original model, (4) we differentiate the efficient units to improve discriminatory power in SRDM, and (5) we provide two numerical examples to elucidate the details of the proposed method

Colorimetric detection of chromium(VI) ions in water using unfolded-fullerene carbon nanoparticles

Water pollution caused by hexavalent chromium (Cr(VI)) ions represents a serious hazard for human health due to the high systemic toxicity and carcinogenic nature of this metal species. The optical sensing of Cr(VI) through specifically engineered nanomaterials has recently emerged as a versatile strategy for the application to easy-to-use and cheap monitoring devices. In this study, a one-pot oxidative method was developed for the cage opening of C60 fullerene and the synthesis of stable suspensions of N-doped carbon dots in water–THF solutions (N-CDs-W-THF). The N-CDs-W-THF selectively showed variations of optical absorbance in the presence of Cr(VI) ions in water through the arising of a distinct absorption band peaking at 550 nm, i.e., in the transparency region of pristine material. Absorbance increased linearly, with the ion concentration in the range 1–100 µM, thus enabling visual and ratiometric determination with a limit of detection (LOD) of 300 nM. Selectivity and possible interference effects were tested over the 11 other most common heavy metal ions. The sensing process occurred without the need for any other reactant or treatment at neutral pH and within 1 min after the addition of chromium ions, both in deionized and in real water sam-ples

Strain balancing of MOVPE InAs/GaAs quantum dots using GaAs0.8P0.2

MOVPE growth of stacked InAs/ GaAs QDs with and without GaAs 0.8 P 0.2 strain balancing layers has been studied. The GaAsP layers reduce the accumulated strain whilst maintaining the electrical characteristics. This should enable closer stacking of QD layers leading to higher gain and improved laser performance

Strain Balancing of Metal-Organic Vapour Phase Epitaxy InAs/GaAs Quantum Dot Lasers

Incorporation of a GaAs0.8P0.2 layer allows strain balancing to be achieved in self-assembled InAs/GaAs quantum dots (QDs) grown by metal organic vapor phase epitaxy. Tuneable wavelength and high density are obtained through growth parameter optimization, with emission at 1.27 μm and QD layer density 3 × 10 10 cm-2. Strain balancing allows close vertical stacking (30 nm) of the QD layers, giving the potential for increased optical gain. Modeling and device characterization indicates minimal degradation in the optical and electrical characteristics unless the phosphorus percentage is increased above 20%. Laser structures are fabricated with a layer separation of 30 nm, demonstrating low temperature lasing with a threshold current density of 100 A/cm2 at 130 K without any facet coating

Charge control in InP/GaInP single quantum dots embedded in Schottky diodes

We demonstrate control by applied electric field of the charge states in single self-assembled InP quantum dots placed in GaInP Schottky structures grown by metalorganic vapor phase epitaxy. This has been enabled by growth optimization leading to suppression of formation of large dots uncontrollably accumulating charge. Using bias- and polarization-dependent micro-photoluminescence, we identify the exciton multi-particle states and carry out a systematic study of the neutral exciton state dipole moment and polarizability. This analysis allows for the characterization of the exciton wavefunction properties at the single dot level for this type of quantum dots. Photocurrent measurements allow further characterization of exciton properties by electrical means, opening new possibilities for resonant excitation studies for such system.Comment: 7 pages, 4 figure

High-powEr Phosphorous-based DFB Lasers for Cold Atom Systems (HELCATS)

No abstract available

Education and training needs, methods, and tools

The importance of education and training in the domain of power and energy systems targeting the topics of cyber-physical energy systems/smart grids is discussed in this chapter. State-of-the art laboratory-based and simulation-based tools are presented, aiming to address the new educational needs

Impact of health literacy and self-care behaviors on health-related quality of life in Iranians with type 2 diabetes: a cross-sectional study

Background: Regarding the importance of health literacy as a key factor in self-care, appropriate understanding of health information by patients with type 2 diabetes mellitus (T2DM) is fundamental for better management of risk factors, which can also benefit their quality of life. This study aimed to describe the relationship between health literacy (HL), and self-care behaviors with health-related quality of life (HRQL) in patients with T2DM. Methods: A cross-sectional survey was done in Iran in 2019. Patients were recruited randomly from health centers by medical records (n = 192, 55.2 male, mean age 58.12 years). The data collection included demographic form, health literacy questionnaire, diabetes self-care behavior questionnaire, and world health organization�s Quality of Life-BREF (WHOQOL-BREF). Analyses were adjusted for confounders using hierarchical regression analysis. Results: HL as predictor variables explained 47.5 of variance in overall HRQL (p value < 0.001), reading health information was the strongest HL dimension (β = 0.478). Self-care behaviors explained an additional 13.6 of the HRQL variance. In total, 65.5 of the variation in the HRQL is explained by the HL, self-care behavior, and the demographic variables. Conclusion: We found that more almost two-third of the HRQL explained by the HL and self-care behaviors. Given the importance of health literacy and self-care behaviors in the quality of life in patients with T2DM, adoption of health-promoting behaviors and increasing health literacy can be beneficial for promoting quality of life among these patients. © 2020, The Author(s)

Randomized, double-blind comparison of once-weekly dalbavancin versus twice-daily linezolid therapy for the treatment of complicated skin and skin structure infections

Background. Dalbavancin, a novel lipoglycopeptide with a pharmacokinetic profile that allows weekly dosing, is active against gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The efficacy of dalbavancin for treatment of skin and skin structure infections (SSSIs) was demonstrated in a phase 2 study. Methods. In a phase 3 noninferiority study, patients with complicated SSSIs, including infections known or suspected to involve MRSA, were randomized (ratio, 2:1) in a double-blind manner to receive dalbavancin (1000 mg given intravenously on day 1 and 500 mg given intravenously on day 8) or linezolid (600 mg given intravenously or intravenously/orally every 12 h for 14 days). Efficacy was assessed by determining clinical and microbiological responses at the end of therapy and at the test-of-cure visit. Relapses were identified by additional follow-up ~1 month later. Results. MRSA was identified in 51% of patients from whom a pathogen was isolated at baseline. Dalbavancin and linezolid demonstrated comparable clinical efficacy in the clinically evaluable population at the test-of-cure visit (88.9% and 91.2% success, respectively). The rate of clinical success at the end of therapy was >90% in both arms. Less than 1.0% of patients in either treatment arm experienced relapse after the test-of-cure visit. Both treatments yielded successful microbiological response in excess of 85% among microbiologically evaluable patients at end of therapy and at the test-of-cure visit for all pathogens combined, for all S. aureus strains, and for MRSA. Gastrointestinal symptoms were among the most common adverse events in both arms. A higher proportion of patients in the linezolid arm reported adverse events that were judged by the investigator to be probably/possibly related to treatment (dalbavancin arm, 25.4% of subjects; linezolid arm, 32.2% of subjects). Conclusions. Two doses of dalbavancin (1000 mg given on day 1 followed by 500 mg given on day 8) were as well tolerated and as effective as linezolid given twice daily for 14 days for the treatment of patients with complicated SSSI, including those infected with MRSA.Peer reviewe