The Stock Market Valuation of R&D Leaders

We examine future excess returns, earnings variability and stock volatility of R&D Leaders and Followers. Drawing on the business strategy literature, which makes a clear distinction between R&D Leaders and Followers, we show that R&D Leaders do earn significant future excess returns, while R&D Followers just earn average returns. We further document that R&D Leaders generate higher future sales growth, and return-on-assets than Followers. We also tackle the perennial question of whether the excess returns subsequent to R&D are due to mispricing or risk, and show that only a small part of the returns can be attributed to risk compensation. Finally, it has been documented that R&D expenditures are strongly associated with future earnings volatility, suggesting that R&D is less reliable (verifiable) an asset than physical capital. We show that the association between R&D intensity and future earnings volatility of R&D Leaders is not lower than that of R&D Followers. Thus, penetrating the population of R&D firms to distinguish between R&D Leaders and Followers, we bridge the chasm between the major findings of the economics/finance strand and the accounting body of R&D research

STEM Education Practices: Examination of the Argumentation Skills of Pre-service Science Teachers

The aim of this research is to examine the pre-service science teachers’ progress in structuring their argumentation components during the STEM education practices. In the research were worked with 9 pre-service science teachers who are 3rd grade students and took the course of 'Science Laboratory Practices' in a state university. The research is a case study. In the research, structured and unstructured activities were applied for 9 weeks. In structured practices, instructions were followed to show how simple machines are constructed. Unstructured practices were based on the design of pre-service science teachers. The data of the research is obtained through voice recordings, unstructured observation. Argumentation components were examined according to the descriptive analysis approach. As a result of analysis of obtained data; pre-service science teachers have made great progress in constructing argumentation components (claim, evidence, reasoning and rebuttal), and the average score of the rebuttal was found to be lower than the other components. The results obtained from this study demonstrate that STEM education is an effective approach to improving the argumentation skill. Argumentation takes part in engineering design processes which have great importance in STEM practices; given its major role in identifying problems, development of possible solutions and determination, evaluation and discussion of most plausible ones. Therefore argumentation approach can be included as part of STEM education. Keywords: STEM education, argumentation, science education, pre-service science teacher

Perturbation theory in a framework of iteration methods

In a previous paper (J. Phys. A 36, 11807 (2003)), we introduced the `asymptotic iteration method' for solving second-order homogeneous linear differential equations. In this paper, we study perturbed problems in quantum mechanics and we use the method to find the coefficients in the perturbation series for the eigenvalues and eigenfunctions directly, without first solving the unperturbed problem.Comment: 13 page

Czy łagodny stan przedrzucawkowy powoduje sztywność tętnic i przebudowę komory serca poprzez zapalenie?

Background: A link between preeclampsia (PE) and excessive maternal morbidity and mortality is a commonly recognized fact. Moreover, it has been suggested that chronic inflammatory state connected with PE contributes to accelerated atherosclerosis. There is also an association between PE and maternal cardiac remodeling and biventricular diastolic dysfunction. The aim of the study was to investigate the presence of impaired myocardial performance and increased arterial stiffness in patients who experienced a mild case of PE five years previously. Methods: The study included forty PE patients (40 women; mean age 33.75±7.95) and 27 healthy volunteers (27 women; mean age 36.44±10.45)Transthoracic echocardiography, including Doppler echocardiography combined with tissue Doppler imaging (TDI), and aortic stiffness index (AoSI), aortic distensibility (AoD), and aortic elastic modulus (AoEM) values were measured in each study participant. Results: There was a statistically significant increase in hsCRP, aortic stiffness index, and aortic elastic modulus in PE patients as compared to controls (2.43±1.91 vs. 3.80±2.06, p=0.007; 3.09±2.41 vs. 7.32±6.89, p=0.001; 2.89±2.11 vs. 7.00± 6.83, p=0.001), while a significant decrease was observed in the aortic strain and distensibility (respectively, 22.35±15.99 vs. 12.24±9.22, p=0.005; 11.17±9.68 vs. 6.13±4.99, p=0.018). No differences between the two groups were observed with regard to the left ventricular myocardial performance index (MPI) (0.55±0.16 vs. 0.53± 0.19, p= 0.630). Conclusions: To the best of our knowledge, this has been the first study to demonstrate impaired aortic elasticity and unaffected myocardial performance index in patients with mild PE. Moreover, these effects turned out to be significantly correlated with inflammation.Wstęp: Istnieje powiązanie pomiędzy stanem przedrzucawkowym (PE) a nadmierną zachorowalnością i śmiertelnością. Ponadto, sugeruje się, że przewlekły stan zapalny udzielający się w PE przyczynia się do przyspieszenia miażdżycy. Istnieje również związek między PE przebudowy mięśnia sercowego ze strony matki i dwukomorową dysfunkcją rozkurczową. Zaplanowaliśmy ocenić w tym badaniu, czy nie została osłabiona wydolność mięśnia sercowego oraz zwiększenie sztywności tętnic u pacjentek, które pięć lat wcześniej miały łagodny przypadek PE. Metody: W badanie włączonych zostało czterdzieści pacjentek (40 kobiet; średnia wieku 33,75±7,95) oraz 27 zdrowych ochotniczek (27 kobiet: średnia wieku: 36,44±10,45). Każda z pacjentek została zbadana za pomocą echokardiografii przezklatkowej, w tym echokardiografii dopplerowskiej w połączeniu z tkankową echokardiografią dopplerowską (TDI). Zostały również zmierzone takie wartości, jak wskaźnik sztywności aorty (AoSI), rozciągliwość aorty, a także moduł sprężystości aorty (AoEM). Wyniki: Stwierdzono statystycznie istotny wzrost hsCRP, wskaźnika sztywności aorty i modułu sprężystości aorty u pacjentów z PE w porównaniu z grupą kontrolną (2,43±1,91vs. 3,80±2,06, p=0.007; 3,09±2,41 vs. 7,32±6,89, p=0,001; 2,89±2,11 vs. 7,00± 6,83, p=0,001), natomiast znaczne zmniejszenie zaobserwowano w odkształceniu aorty i jej rozciągliwości (odpowiednio 22,35±15,99 vs. 12,24±9,22, p= 0,005; 11,17±9,68 vs. 6,13±4,99, p=0.018). Nie wystąpiły różnice pomiędzy tymi dwoma grupami w odniesieniu do wskaźnika wydolności mięśnia sercowego lewej komory (0,55± 0,16 vs 0,53± 0,19, p=0,630). Wnioski: Stwierdziliśmy po raz pierwszy w tym badaniu, że wystąpiły osłabiona elastyczność aorty i niezmieniony wskaźnik wydolność mięśnia sercowego (MPI) u pacjentek z łagodnym PE, ponadto, efekty te były znacząco skorelowane ze stanem zapalnym

The Stock Market Valuation of R&D Leaders

We examine future excess returns, earnings variability and stock volatility of R&D Leaders and Followers. Drawing on the business strategy literature, which makes a clear distinction between R&D Leaders and Followers, we show that R&D Leaders do earn significant future excess returns, while R&D Followers just earn average returns. We further document that R&D Leaders generate higher future sales growth, and return-on-assets than Followers. We also tackle the perennial question of whether the excess returns subsequent to R&D are due to mispricing or risk, and show that only a small part of the returns can be attributed to risk compensation. Finally, it has been documented that R&D expenditures are strongly associated with future earnings volatility, suggesting that R&D is less reliable (verifiable) an asset than physical capital. We show that the association between R&D intensity and future earnings volatility of R&D Leaders is not lower than that of R&D Followers. Thus, penetrating the population of R&D firms to distinguish between R&D Leaders and Followers, we bridge the chasm between the major findings of the economics/finance strand and the accounting body of R&D research

d-Dimensional generalization of the point canonical transformation for a quantum particle with position-dependent mass

The d-dimensional generalization of the point canonical transformation for a quantum particle endowed with a position-dependent mass in Schrodinger equation is described. Illustrative examples including; the harmonic oscillator, Coulomb, spiked harmonic, Kratzer, Morse oscillator, Poschl-Teller and Hulthen potentials are used as reference potentials to obtain exact energy eigenvalues and eigenfunctions for target potentials at different position-dependent mass settings.Comment: 14 pages, no figures, to appear in J. Phys. A: Math. Ge

Perovskite Nanoparticles

2D perovskite nanoparticles have a great potential for using in optoelectronic devices such as Solar Cells and Light Emitting Diodes within their tuneable optic and structural properties. In this chapter, it is aimed to express “relation between chemical structures and photo-physical behaviours of perovskite nanoparticles and milestones for their electronic applications”. Initially, general synthesis methods of perovskite nanoparticles have been explained. Furthermore, advantages and disadvantages of the methods have been discussed. After the synthesis, formation of 2D perovskite crystal and effects on shape factor, particle size and uniformity of perovskite have been explained in detail. Beside these, optic properties of luminescent perovskite nanoparticles have been summarized a long with spectral band tuning via size and composition changes. In addition, since their different optical properties and relatively more stable chemical structure under ambient conditions, a comprehensive compilation of opto-electronic applications of 2D perovskite nanoparticles have been prepared

Study of a class of non-polynomial oscillator potentials

We develop a variational method to obtain accurate bounds for the eigenenergies of H = -Delta + V in arbitrary dimensions N>1, where V(r) is the nonpolynomial oscillator potential V(r) = r^2 + lambda r^2/(1+gr^2), lambda in (-infinity,\infinity), g>0. The variational bounds are compared with results previously obtained in the literature. An infinite set of exact solutions is also obtained and used as a source of comparison eigenvalues.Comment: 16 page

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised