Hemiprosthesis for Femoral Neck Fractures in the Elderly: A Retrospective Study of 319 Patients

Background: In geriatric patients with Pauwels types II and III femoral neck fractures, hemiprosthesis is the therapy of choice. Objectives: This study was conducted to analyze the results after cemented hemiprosthesis placement, the first year after surgery. Patients and Methods: This retrospective study was conducted on 319 patients over 70 years with displaced femoral neck fractures treated surgically at our hospital from 2007 to 2012. All medical information was available including retrospective posthospital discharge records as well as inpatient course and one-year mortality. Results: From a total of 319 patients, 78% (n = 249) were female and 22% (n = 70) were male, with the mean age of 83.6 years. Seventeen percent of the patients suffered from heart failure, 23% from diabetes, and 19% from renal insufficiency. Time to surgery averaged one day postinjury. Average operative time skin-to-skin was 50 minutes. Seventy-three percent of the patients could mobilize independently on discharge. Of the remaining patients, 2/3 had already lost independent mobilization prior to the fracture. Hospital mortality averaged 5% (national average in Germany: 8%), and 30-day and 90-day mortality rates were 5% and 15%, respectively. Within one year, 22% of the patients died (national average: 27%). Also, 14 patients were re-admitted, for contralateral prosthetic implantation (n = 7) or revision after the periprosthetic fracture (n = 5). Fifty-three percent of the patients were admitted to hospital during the year for other diseases (national average: 54%). Conclusions: Hemiprosthesis placement for displaced femoral neck fractures is a common and safe procedure. Despite recent decreases in hospital mortality, the risk of death remains more than twice as high within one year than that for uninjured patients of the same age

Determining Factors of the Czech Foreign Trade Balance: Structural Issues in Trade Creation

Using panel data for 29 industries, we test alternative specifications of Czech export and import functions. The balance of trade is primarily influenced by the real exchange rate, aggregate demand and tariff changes. Reduced growth of the Czech economy after 1996 was an important factor that has kept the balance of trade at a sustainable level in the medium-term, contributing even to the appreciation of the real exchange rate. The secondary fundamental factors, relevant for structural adjustments, a sustainable trade balance and an equilibrium exchange rate, rest, however, on supply-side characteristics such as changes in endowments of physical and human capital, inflows of FDI and growing competitiveness of domestic production. We can argue that appreciation of the real exchange rate is a handicap to Czech exports, especially to exports to non-EU countries. Nevertheless, in the EU case, the appreciation of koruna was countervailed by tariff concessions, improved quality, switchover to commodities with higher contents of value added, gains associated with FDI and growing foreign demand absorption. At the same time, appreciation of the real exchange rate has significantly opened the Czech market to imports but the unconstrained import penetration remained blocked by the growing competitiveness of Czech products in costs, prices and quality.export and import specialisation; international trade; panel data estimation; production factor intensities; sectoral trade balance.

Theoretical analysis of electronic band structure of 2-to-3-nm Si nanocrystals

We introduce a general method which allows reconstruction of electronic band structure of nanocrystals from ordinary real-space electronic structure calculations. A comprehensive study of band structure of a realistic nanocrystal is given including full geometric and electronic relaxation with the surface passivating groups. In particular, we combine this method with large scale density functional theory calculations to obtain insight into the luminescence properties of silicon nanocrystals of up to 3 nm in size depending on the surface passivation and geometric distortion. We conclude that the band structure concept is applicable to silicon nanocrystals with diameter larger than $\approx$ 2 nm with certain limitations. We also show how perturbations due to polarized surface groups or geometric distortion can lead to considerable moderation of momentum space selection rules

Enhanced low-energy γ\gamma-decay strength of 70^{70}Ni and its robustness within the shell model

Neutron-capture reactions on very neutron-rich nuclei are essential for heavy-element nucleosynthesis through the rapid neutron-capture process, now shown to take place in neutron-star merger events. For these exotic nuclei, radiative neutron capture is extremely sensitive to their $\gamma$-emission probability at very low $\gamma$ energies. In this work, we present measurements of the $\gamma$-decay strength of $^{70}$Ni over the wide range $1.3 \leq E_{\gamma} \leq 8$ MeV. A significant enhancement is found in the $\gamma$-decay strength for transitions with $E_\gamma < 3$ MeV. At present, this is the most neutron-rich nucleus displaying this feature, proving that this phenomenon is not restricted to stable nuclei. We have performed $E1$-strength calculations within the quasiparticle time-blocking approximation, which describe our data above $E_\gamma \simeq 5$ MeV very well. Moreover, large-scale shell-model calculations indicate an $M1$ nature of the low-energy $\gamma$ strength. This turns out to be remarkably robust with respect to the choice of interaction, truncation and model space, and we predict its presence in the whole isotopic chain, in particular the neutron-rich $^{72,74,76}\mathrm{Ni}$.Comment: 9 pages, 9 figure

Beta-delayed gamma decay of 26P: Possible evidence of a proton halo

Background: Measurements of $\beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform nuclear astrophysics studies. Purpose: To measure the $\beta$-delayed $\gamma$ decay of $^{26}$P and compare the results with previous experimental results and shell-model calculations. Method: A $^{26}$P fast beam produced using nuclear fragmentation was implanted into a planar germanium detector. Its $\beta$-delayed $\gamma$-ray emission was measured with an array of 16 high-purity germanium detectors. Positrons emitted in the decay were detected in coincidence to reduce the background. Results: The absolute intensities of $^{26}$P $\beta$-delayed $\gamma$-rays were determined. A total of six new $\beta$-decay branches and 15 new $\gamma$-ray lines have been observed for the first time in $^{26}$P $\beta$-decay. A complete $\beta$-decay scheme was built for the allowed transitions to bound excited states of $^{26}$Si. $ft$ values and Gamow-Teller strengths were also determined for these transitions and compared with shell model calculations and the mirror $\beta$-decay of $^{26}$Na, revealing significant mirror asymmetries. Conclusions: A very good agreement with theoretical predictions based on the USDB shell model is observed. The significant mirror asymmetry observed for the transition to the first excited state ($\delta=51(10)\%$) may be evidence for a proton halo in $^{26}$P.Comment: 15 pages, 10 figures, 7 table

Isobaric multiplet mass equation in the A=31A=31 T=3/2T = 3/2 quartets

The observed mass excesses of analog nuclear states with the same mass number $A$ and isospin $T$ can be used to test the isobaric multiplet mass equation (IMME), which has, in most cases, been validated to a high degree of precision. A recent measurement [Kankainen et al., Phys. Rev. C 93 041304(R) (2016)] of the ground-state mass of $^{31}$Cl led to a substantial breakdown of the IMME for the lowest $A = 31, T = 3/2$ quartet. The second-lowest $A = 31, T = 3/2$ quartet is not complete, due to uncertainties associated with the identity of the $^{31}$S member state. Using a fast $^{31}$Cl beam implanted into a plastic scintillator and a high-purity Ge $\gamma$-ray detection array, $\gamma$ rays from the $^{31}$Cl$(\beta\gamma)$$^{31}$S sequence were measured. Shell-model calculations using USDB and the recently-developed USDE interactions were performed for comparison. Isospin mixing between the $^{31}$S isobaric analog state (IAS) at 6279.0(6) keV and a nearby state at 6390.2(7) keV was observed. The second $T = 3/2$ state in $^{31}$S was observed at $E_x = 7050.0(8)$ keV. Isospin mixing in $^{31}$S does not by itself explain the IMME breakdown in the lowest quartet, but it likely points to similar isospin mixing in the mirror nucleus $^{31}$P, which would result in a perturbation of the $^{31}$P IAS energy. USDB and USDE calculations both predict candidate $^{31}$P states responsible for the mixing in the energy region slightly above $E_x = 6400$ keV. The second quartet has been completed thanks to the identification of the second $^{31}$S $T = 3/2$ state, and the IMME is validated in this quartet

Screening High School Students for Eating Disorders: Results of a National Initiative

Introduction: Early identification and treatment of disordered eating and weight control behaviors may prevent progression and reduce the risk of chronic health consequences. Methods: The National Eating Disorders Screening Program coordinated the first-ever nationwide eating disorders screening initiative for high schools in the United States in 2000. Students completed a self-report screening questionnaire that included the Eating Attitudes Test (EAT-26) and items on vomiting or exercising to control weight, binge eating, and history of treatment for eating disorders. Multivariate regression analyses examined sex and racial/ethnic differences. Results: Almost 15% of girls and 4% of boys scored at or above the threshold of 20 on the EAT-26, which indicated a possible eating disorder. Among girls, we observed few significant differences between ethnic groups in eating disorder symptoms, whereas among boys, more African American, American Indian, Asian/Pacific Islander, and Latino boys reported symptoms than did white boys. Overall, 25% of girls and 11% of boys reported disordered eating and weight control symptoms severe enough to warrant clinical evaluation. Of these symptomatic students, few reported that they had ever received treatment. Conclusion: Population screening for eating disorders in high schools may identify at-risk students who would benefit from early intervention, which could prevent acute and long-term complications of disordered eating and weight control behaviors

Study of the island morphology at the early stages of Fe/Mo(110) MBE growth

We present theoretical study of morphology of Fe islands grown at Mo(110) surface in sub-monolayer MBE mode. We utilize atomistic SOS model with bond counting, and interactions of Fe adatom up to third nearest neighbors. We performed KMC simulations for different values of adatom interactions and varying temperatures. We have found that, while for the low temperature islands are fat fractals, for the temperature 500K islands have faceted rhombic-like shape. For the higher temperature, islands acquire a rounded shape. In order to evaluated qualitatively morphological changes, we measured averaged aspect ration of islands. We calculated dependence of the average aspect ratio on the temperature, and on the strength of interactions of an adatom with neighbors.Comment: 6 pages, 6 figures. Proceedings of 11-th Symposium on Surface Physics, Prague 200