bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Bariatric Surgery on Pancreatic Lipid Metabolism and Blood Flow
Authors: Honka Henri , Koffert Jukka , Hannukainen Jarna C. , Tuulari Jetro J. , Karlsson Henry K. , Immonen Heidi , Oikonen Vesa , Tolvanen Tuula , Soinio Minna , Salminen Paulina , Kudomi Nobu , Mari Andrea , Iozzo Patricia , Nuutila Pirjo
Published: March 2015

Context:

Bariatric surgery leads to a rapid and sustained weight loss often accompanied with improvement in glucose homeostasis.

Objective:

The objective of this study was to investigate the effects of bariatric surgery on pancreatic lipid metabolism, blood flow, and glycemic control.

Design:

This was a longitudinal study.

Setting:

The study was conducted in a clinical research center.

Participants:

This study included 27 morbidly obese and 15 healthy control subjects.

Interventions:

Measurements were performed using positron emission tomography with the palmitate analog 14(R,S)-[18F]fluoro-6-thia-heptadecanoic acid and radiowater ([15O]H2O) and computed tomography. In morbidly obese subjects, positron emission tomography/computed tomography imaging studies were performed before and 6 months after bariatric surgery (either Roux-en-Y gastric bypass or sleeve gastrectomy).

Main Outcome Measures:

Pancreatic fat and fat-free volume, fatty acid uptake and blood flow were measured as well as parameters of β-cell function, glucose tolerance, and insulin sensitivity.

Results:

Six months after bariatric surgery, 23% excess weight loss was observed (P < .0001), and diabetes remission was seen in 7 of 10 patients. When compared with preoperative values, after surgery, notable decreases in pancreatic fat volume (P < .01), fatty acid uptake, and blood flow (both P < .05) were seen, whereas no change was seen in pancreatic fat-free volume. The decrease in pancreatic fat volume and the preservation of blood flow were associated with favorable glucose homeostasis and β-cell function.

Conclusions:

Bariatric surgery elicits marked alterations in pancreatic lipid metabolism and blood flow, which may contribute to the observed improvement in glucose homeostasis and remission of type 2 diabetes.
17β-Estradiol Increases Persistent Na+ Current and Excitability of AVPV/PeN Kiss1 Neurons in Female Mice
Authors: Zhang Chunguang , Bosch Martha A. , Qiu Jian , Rønnekleiv Oline K. , Kelly Martin J.
Published: March 2015

In vitro slice studies have revealed that there are significant differences in the spontaneous firing activity between anteroventral periventricular/periventricular preoptic nucleus (AVPV/PeN) and arcuate nucleus (ARC) kisspeptin (Kiss1) neurons in females. Although both populations express similar endogenous conductances, we have discovered that AVPV/PeN Kiss1 neurons express a subthreshold, persistent sodium current (INaP) that dramatically alters their firing activity. Based on whole-cell recording of Kiss1-Cre-green fluorescent protein (GFP) neurons, INaP was 4-fold greater in AVPV/PeN vs ARC Kiss1 neurons. An LH surge-producing dose of 17β-estradiol (E2) that increased Kiss1 mRNA expression in the AVPV/PeN, also augmented INaP in AVPV/PeN neurons by 2-fold. Because the activation threshold for INaP was close to the resting membrane potential (RMP) of AVPV/PeN Kiss1 neurons (−54 mV), it rendered them much more excitable and spontaneously active vs ARC Kiss1 neurons (RMP = −66 mV). Single-cell RT-PCR revealed that AVPV/PeN Kiss1 neurons expressed the requisite sodium channel α-subunit transcripts, NaV1.1, NaV1.2, and NaV1.6 and β subunits, β2 and β4. Importantly, NaV1.1α and -β2 transcripts in AVPV/PeN, but not ARC, were up-regulated 2- to 3-fold by a surge-producing dose of E2, similar to the transient calcium current channel subunit Cav3.1. The transient calcium current collaborates with INaP to generate burst firing, and selective blockade of INaP by riluzole significantly attenuated rebound burst firing and spontaneous activity. Therefore, INaP appears to play a prominent role in AVPV/PeN Kiss1 neurons to generate spontaneous, repetitive burst firing, which is required for the high-frequency-stimulated release of kisspeptin for exciting GnRH neurons and potentially generating the GnRH surge.
The War on Poverty's Experiment in Public Medicine: Community Health Centers and the Mortality of Older Americans
Authors: Bailey Martha J. , Goodman-Bacon Andrew
Published: March 2015

This paper uses the rollout of the first Community Health Centers (CHCs) to study the longer-term health effects of increasing access to primary care. Within ten years, CHCs are associated with a reduction in age-adjusted mortality rates of 2 percent among those 50 and older. The implied 7 to 13 percent decrease in one-year mortality risk among beneficiaries amounts to 20 to 40 percent of the 1966 poor/non-poor mortality gap for this age group. Large effects for those 65 and older suggest that increased access to primary care has longer-term benefits, even for populations with near universal health insurance. (JEL H75, I12, I13, I18, I32, I38, J14)
The Limits of Price Discrimination
Authors: Bergemann Dirk , Brooks Benjamin , Morris Stephen
Published: March 2015

We analyze the welfare consequences of a monopolist having additional information about consumers' tastes, beyond the prior distribution; the additional information can be used to charge different prices to different segments of the market, i.e., carry out “third degree price discrimination.” We show that the segmentation and pricing induced by the additional information can achieve every combination of consumer and producer surplus such that: (i) consumer sur plus is nonnegative, (ii) producer surplus is at least as high as profits under the uniform monopoly price, and (iii) total surplus does not exceed the surplus generated by efficient trade. (JEL D42, D83, L12)
Noise Levels in Twenty Selected Cinema Theatres in Visakhapatnam City, Andhra Pradesh, India
Authors: Rao N Someswara , Ajay B , Ramesh B Santosh , Naidu G Gowri , Krishna L Pattabi Rama , Krishna L Mohana
Published: March 2015

Cinema is the most important media for entertainment and relaxation in India. Noise is an important pollutant in cinema theaters. People are ignorant of the ill effects of noise. Frequent exposure to loud music can lead to selective hearing loss at some frequencies depending on age and gender and the common ear disorders are tinnitus and hyperacousis. The noise levels in twenty selected cinema theatres playing different types of movies in Visakhapatnam city, Andhra Pradesh, India were measured using CYGNET 2001 and a questionnaire survey was done to determine the effect of noise on the audience. The LAeq levels ranged from 78 to 93 dB (A) in the twenty selected cinema theatres and the corresponding the 8-hour daily exposure LAeq8h levels are in the range 73 to 87 dB (A). The LAeq levels in eleven theatres (55%) are above 85 dB (A), in eight theatres (40%) the levels are between 80–85 dB (A) and one theatre (5%) the level is less than 80 dB (A). At eight theatres, about 65% of audience in the age group of 40 years and above expressed mild to severe headache and tinnitus whereas 10% of audience above age of 30 years expressed slight uneasiness.
From Aerodynamics towards Aeroacoustics: A Novel Natural Velocity Decomposition for the Navier-Stokes Equations
Authors: Morino Luigi , Gradassi Paolo
Published: March 2015

A novel formulation for the analysis of viscous incompressible and compressible aerodynamics/aeroacoustics fields is presented. The paper is primarily of a theoretical nature, and presents the transition path from aerodynamics towards aeroacoustics. The basis of the paper is a variant of the so-called natural velocity decomposition, as v = ▿φ + w, where w is obtained from its own governing equation and not from the vorticity. With the novel decomposition, the governing equation for w and the generalized Bernoulli theorem for viscous fields assume a very elegant form. Another improvement pertains to the so-called material covariant components of w: For inviscid incompressible flows, they remain constant in time; minor modifications occur when we deal with viscous flows. In addition, interesting simplifications of the formulation are presented for almost-potential flows, namely for flows that are irrotational everywhere except for thin vortex layers, such as boundary layers and wakes. It is shown that, if the thickness is very small, the exact formulation for almost-potential flows is approximately equal to that for quasi-potential flows (zero-thickness wake), as modified by the Lighthill transpiration velocity correction. Simple numerical applications to the flow around a disk and to jet aerodynamics/aeroacoustics (Kelvin-Helmholtz instabilities) are included.
On the Extrapolation of Acoustic Waves from Flow Simulations with Vortical out Flow
Authors: Wright M. C. M. , Morfey C. L.
Published: March 2015

Feri Farassat was one of the pioneers of the use of the Ffowcs Williams & Hawkings formulation of Lighthill's acoustic analogy as a way to extrapolate radiated waves from simulations of unsteady flows. Current computational limits mean that volume source terms are often neglected, causing inaccurate acoustical predictions when entropy fluctuations or vorticity pass across the extrapolation surface. The derivation of the Ffowcs Williams–Hawkings equation is modified to allow the equivalent surface sources to be distributed over a transition layer of finite thickness rather than being confined to a single layer, in order to reduce the effect of vorticity exiting the computational domain.
The Scaling of Broadband Shock-Associated Noise with Increasing Temperature
Authors: Miller Steven A. E.
Published: March 2015

A physical explanation for the saturation of broadband shock-associated noise (BBSAN) intensity with increasing jet stagnation temperature has eluded investigators. An explanation is proposed for this phenomenon with the use of an acoustic analogy. To isolate the relevant physics, the scaling of BBSAN peak intensity level at the sideline observer location is examined. The equivalent source within the framework of an acoustic analogy for BBSAN is based on local field quantities at shock wave – shear layer interactions. Propagation of sound through the jet shear layer is predicted with an adjoint vector Green's function solver of the linearized Euler equations. The combination of the equivalent source and adjoint vector Green's function allows for correct predictions of the saturation of BBSAN with increasing stagnation pressure and stagnation temperature. The sources and vector Green's function have arguments involving the steady Reynolds-Averaged Navier-Stokes solution of the jet. It is proposed that saturation of BBSAN with increasing jet temperature occurs due to a balance between the amplification of the sound propagation through the shear layer and the source term scaling.
The Use of an Adjoint Method for Optimization of Blowing in a Convergent-Divergent Nozzle
Authors: Sikarwar Nidhi , Morris Philip J.
Published: March 2015

This paper describes an adjoint optimization method. It is used to determine the blowing distribution in the diverging section of a convergent-divergent nozzle that gives a desired pressure distribution in the nozzle. The study is motivated by a noise reduction concept described by Morris et al. [11, 12] in which distributed blowing in the nozzle divergent section is used to repro- duce the effect of the corrugated seals developed by Seiner et al. [15, 14]. Both approaches reduce broadband shock-associated noise by allowing the nozzle to operate closer to an on-design condition. In addition, streamwise vortices are produced that break up the large scale structures in the jet and reduce mixing noise in the peak noise radiation direction. The design of the distributed blowing involves many parameters: Both in the injector geometry and operating conditions. This design problem is ideally suited to the adjoint optimization method. The present paper provides a framework for this design process. The paper develops both the direct and adjoint problems and their associated boundary conditions. Two simple example problems are described. In the first, a prescribed blowing distribution is imposed and the resulting pressure distribution in the nozzle is calculated. This pressure distribution is used as the target or desired distribution and the required distributed blowing to achieve this target, starting from zero blowing, is determined using the adjoint method. In the second case blowing is introduced in a convergent-divergent nozzle containing a shock. The adjoint method is used to determine the blowing distribution required to eliminate the shock.
Some Elegant Derivations Employing Generalized Functions
Authors: Hardin Jay C.
Published: March 2015

This note presents three derivations utilizing generalized function theory. These derivations are much more straightforward than are those employing conventional techniques which illustrate the power of generalized function theory.
Open Rotor Noise Prediction Using the time Domain Formulations of Farassat
Authors: Dunn Mark H. , Tinetti Ana F. , Nark Douglas M.
Published: March 2015

During his career at the NASA Langley Research Center (LaRC), Feridoun (Feri) Farassat (1944–2011) made significant contributions to the understanding of open rotor (OR) noise generating mechanisms and to the development of OR aeroacoustic prediction technology. His time domain solutions of the Ffowcs Williams and Hawkings equation for surfaces in arbitrary motion are valid over all flight speeds ranging from subsonic through transonic to supersonic, and have led to the creation of several open rotor noise prediction programs. Two of these solutions, known as Formulation 1A and Formulation 3, are described here and have been implemented in the open rotor noise prediction codes ASSPIN (Advanced Subsonic and Supersonic Propeller Induced Noise) and ASSPIN2. Validation studies comparing noise predictions made with these codes to measured noise data are presented for a full-scale, single-rotation propfan at cruise conditions and for sub-scale, contra-rotating rotors at take-off conditions. In his later years, Farassat collaborated with the authors on the development of level 1 (non-CFD) blade aerodynamics codes for providing low-cost, time domain, blade surface pressure data for ASSPIN2 input. Use of the level 1 aerodynamics codes and their interaction with ASSPIN2 are demonstrated with noise radiation studies for a model SR7 open rotor at take-off and cruise conditions.
Numerical Determination of Equivalent Reflected Blast Parameters Acting on Circular Cross Sections
Authors: Qasrawi Yazan , Heffernan Pat J. , Fam Amir
Published: March 2015

A number of experimenters observed that the blast shockwave loads experienced by circular cross sections were lower than the predicted loads. These observations revealed a gap in the understanding of the interaction between blasts and structures. The question of quantifying these reduced loads for purposes of analysis and design presented itself for investigation. This paper presents the numerical investigation of the blast reflection reduction due to diffraction around a circular cross section using the commercial software ANSYS Autodyn. The investigation focused on the effects of the cross section's diameter and the explosion's scaled distance on the reflected blast pressure and impulse. Nine numerical gauge points recorded pressure-time and impulse-time histories at regular radial intervals around the front quarter of the circular section. The model's results agreed with incident and reflected pressure and impulse design values. The results indicated that as the diameter of the section increased the peak reflected pressure and impulse at the point of incidence rapidly approached the design values. The results also indicated that both the pressure and the impulse varied sinusoidally between a maximum at the point of incidence and a minimum, approximately equal to the incident pressure and impulse, at the side of the section. Using a sinusoidal curve fit to obtain equivalent reflected pressure and impulse values showed that the actual pressure and impulse acting on a circular cross section were approximately half the recommended design values. The results supported the obvious advantages of designing circular members to resist blast loading. Simplified equations are proposed for calculating the equivalent pressure and impulse acting on circular sections from the standard design values.
A Systems View of Vehicle Landmine Survivability
Authors: Cimpoeru S.J. , Phillips P. , Ritzel D.V.
Published: March 2015

The protection of vehicle occupants against landmines is a systems problem which must consider multiple failure paths that can lead to occupant injuries. The response of a vehicle to underbelly blast from a landmine can be divided into three categories: 1) hull response to an immediate external blast load; 2) internal vehicle dynamics; and 3) global vehicle motions. Vehicle survivability is a broad and complex topic which is discussed in these terms and examples of protective subsystem elements are included. This paper argues that decomposing a complex blast protection system into its components from a systems point of view should contribute to the enhanced survivability of vehicle occupants.
Molecular phylogenetics and generic assessment in the tribe Pavetteae (Rubiaceae)
Authors: De Block Petra , Razafimandimbison Sylvain G. , Janssens Steven , Ochoterena Helga , Robbrecht Elmar , Bremer Birgitta
Published: March 2015

This is the first phylogenetic study focused on the Pavetteae, one of the most species‐rich and morphologically diverse tribes within the coffee family (Rubiaceae). Fifteen of the 17 currently recognized genera, represented by 85 taxa, were sequenced for rps16, trnT‐F and ITS and analysed using Bayesian inference and maximum likelihood methods. The monophyly of the Pavetteae is confirmed. Four major lineages are identified, but their phylogenetic relationships are not fully resolved. The continental African genera Rutidea, Nichallea and Tennantia, the Madagascan genera Homollea and Robbrechtia, and the paleotropical genus Pavetta are monophyletic. Other genera are paraphyletic in their current circumscriptions and the following changes are made: Homolliella is placed in synonymy with Paracephaelis, and Coleactina and Dictyandra with Leptactina , resulting in four new combinations. The large paleotropical genus Tarenna is shown not to be monophyletic. In the future, the name Tarenna should not be used for continental African species. Most of these could be transferred to the hitherto monospecific genus Cladoceras, but other species might constitute altogether new genera. The relationship between the monophyletic Asian‐Pacific and Madagascan Tarenna species remains unclear. The phylogeny of the Madagascan genera of the Pavetteae is largely unresolved and the largest Madagascar‐centred genus Coptosperma was not recovered as monophyletic. The low resolution for the Madagascan taxa can be considered as an indication of rapid radiation. Further molecular and morphological studies are necessary to clarify the phylogeny of the Pavetteae, especially regarding the African Tarenna species and the Madagascan genera of the tribe.
Human Capital and Labor Productivity in North Caucasian Federal District of Russia
Authors: Комарова  , Komarova Anna , Кальянов  , Kalyanov Aleksandr
Published: March 2015

A technique based on Russia regions’ economic development analysis (on the

example of human capital and labor productivity in the North Caucasian Federal

District of Russia) by means of creation of econometric models related to labor

productivity in regions of the North Caucasian Federal District of Russia has

been realized. It has been shown that such a factor as an employed population’s

education level is the important one in determining the labor productivity in the

regions of the North Caucasian Federal District of Russia.
Human Capital Influence on Labor Productivity in Far Eastern Federal District
Authors: Комарова  , Komarova Anna
Published: March 2015

A technique based on development of econometric models related to labor

productivity in regions of the Far Eastern Federal District of Russia has been

realized. It has been shown that such a factor as an employed population’s

education level is the important one in determining the labor productivity in the

regions of the Far Eastern Federal District of Russia.
Production and Sales’ Volume Planning Based on Marginal Data Analysis
Authors: Аверина  , Averina Tatyana
Published: March 2015

Logical and convenient methods of economic theory often remain unclaimed in

the area of management accounting and analysis. For example an obstacle to

the use of marginal revenue and marginal cost comparison method may be

difficulties associated with the assembly of these indicators’ equations. This

paper contains an example of using regression analysis for separation the cost

related to constant and variable components, for assembly of marginal data

equations in order to determine the optimum volume of output.
Early surveillance of ceramic-on-metal total hip arthroplasty
Authors: Hill J. C. , Diamond O. J. , O’Brien S. , Boldt J. G. , Stevenson M. , Beverland D. E.
Published: March 2015

Ceramic-on-metal (CoM) is a relatively new bearing combination for total hip arthroplasty (THA) with few reported outcomes. A total of 287 CoM THAs were carried out in 271 patients (mean age 55.6 years (20 to 77), 150 THAs in female patients, 137 in male) under the care of a single surgeon between October 2007 and October 2009. With the issues surrounding metal-on-metal bearings the decision was taken to review these patients between March and November 2011, at a mean follow-up of 34 months (23 to 45) and to record pain, outcome scores, radiological analysis and blood ion levels. The mean Oxford Hip Score was 19.2 (12 to 53), 254 patients with 268 hips (95%) had mild/very mild/no pain, the mean angle of inclination of the acetabular component was 44.8o(28oto 63o), 82 stems (29%) had evidence of radiolucent lines of > 1 mm in at least one Gruen zone and the median levels of cobalt and chromium ions in the blood were 0.83 μg/L (0.24 μg/L to 27.56 μg/L) and 0.78 μg/L (0.21 μg/L to 8.84 μg/L), respectively. The five-year survival rate is 96.9% (95% confidence interval 94.7% to 99%).

Due to the presence of radiolucent lines and the higher than expected levels of metal ions in the blood, we would not recommend the use of CoM THA without further long-term follow-up. We plan to monitor all these patients regularly.

Cite this article: Bone Joint J 2015;97-B:300–5.
Ultrasound-guided gradual reduction using flexion and abduction continuous traction for developmental dysplasia of the hip
Authors: Fukiage K. , Futami T. , Ogi Y. , Harada Y. , Shimozono F. , Kashiwagi N. , Takase T. , Suzuki S.
Published: March 2015

We describe our experience in the reduction of dislocation of the hip secondary to developmental dysplasia using ultrasound-guided gradual reduction using flexion and abduction continuous traction (FACT-R). During a period of 13 years we treated 208 Suzuki type B or C complete dislocations of the hip in 202 children with a mean age of four months (0 to 11). The mean follow-up was 9.1 years (five to 16). The rate of reduction was 99.0%. There were no recurrent dislocations, and the rate of avascular necrosis of the femoral head was 1.0%. The rate of secondary surgery for residual acetabular dysplasia was 19.2%, and this was significantly higher in those children in whom the initial treatment was delayed or if other previous treatments had failed (p = 0.00045). The duration of FACT-R was significantly longer in severe dislocations (p = 0.001) or if previous treatments had failed (p = 0.018).

This new method of treatment is effective and safe in these difficult cases and offers outcomes comparable to or better than those of standard methods.

Cite this article: Bone Joint J 2015;97-B:405–11.
The effect of severing a normal S1 nerve root to use for reconstruction of an avulsed contralateral lumbosacral plexus
Authors: Zhu L. , F. Zhang  , Yang D. , Chen A.
Published: March 2015

The aim of this study was to evaluate the feasibility of using the intact S1 nerve root as a donor nerve to repair an avulsion of the contralateral lumbosacral plexus. Two cohorts of patients were recruited. In cohort 1, the L4–S4 nerve roots of 15 patients with a unilateral fracture of the sacrum and sacral nerve injury were stimulated during surgery to establish the precise functional distribution of the S1 nerve root and its proportional contribution to individual muscles. In cohort 2, the contralateral uninjured S1 nerve root of six patients with a unilateral lumbosacral plexus avulsion was transected extradurally and used with a 25 cm segment of the common peroneal nerve from the injured leg to reconstruct the avulsed plexus.

The results from cohort 1 showed that the innervation of S1 in each muscle can be compensated for by L4, L5, S2 and S3. Numbness in the toes and a reduction in strength were found after surgery in cohort 2, but these symptoms gradually disappeared and strength recovered. The results of electrophysiological studies of the donor limb were generally normal.

Severing the S1 nerve root does not appear to damage the healthy limb as far as clinical assessment and electrophysiological testing can determine. Consequently, the S1 nerve can be considered to be a suitable donor nerve for reconstruction of an avulsed contralateral lumbosacral plexus.

Cite this article: Bone Joint J 2015; 97-B:358–65.
Recovery of health-related quality of life in a United Kingdom hip fracture population
Authors: Griffin X. L. , Parsons N. , Achten J. , Fernandez M. , Costa M. L.
Published: March 2015

Hip fracture is a global public health problem. The National Hip Fracture Database provides a framework for service evaluation in this group of patients in the United Kingdom, but does not collect patient-reported outcome data and is unable to provide meaningful data about the recovery of quality of life.

We report one-year patient-reported outcomes of a prospective cohort of patients treated at a single major trauma centre in the United Kingdom who sustained a hip fracture between January 2012 and March 2014.

There was an initial marked decline in quality of life from baseline measured using the EuroQol 5 Dimensions score (EQ-5D). It was followed by a significant improvement to 120 days for all patients. Although their quality of life improved during the year after the fracture, it was still significantly lower than before injury irrespective of age group or cognitive impairment (mean reduction EQ-5D 0.22; 95% confidence interval (CI) 0.17 to 0.26). There was strong evidence that quality of life was lower for patients with cognitive impairment. There was a mean reduction in EQ-5D of 0.28 (95% CI 0.22 to 0.35) in patients <  80 years of age. This difference was consistent (and fixed) throughout follow-up. Quality of life does not improve significantly during recovery from hip fracture in patients over 80 years of age (p = 0.928). Secondary measures of function showed similar trends.

Hip fracture marks a step down in the quality of life of a patient: it accounts for approximately 0.22 disability adjusted life years in the first year after fracture. This is equivalent to serious neurological conditions for which extensive funding for research and treatment is made available.

Cite this article: Bone Joint J 2015;97-B:372–82.
Errata
Authors: Haddad F. S.
Published: March 2015

DF Hamilton, R Burnett, JT Patton, CR Howie, M Moran, AHRW Simpson, P Gaston. Implant design influences patient outcome after total knee arthroplasty. Bone Joint J 2015;97-B:64–70.
Impact of Leading Presenting Symptoms on the Diagnostic Performance of High-Sensitivity Cardiac Troponin T and on Outcomes in Patients with Suspected Acute Coronary Syndrome
Authors: Biener Moritz , Mueller Matthias , Vafaie Mehrshad , Katus Hugo A , Giannitsis Evangelos
Published: March 2015

BACKGROUND

Diagnostic performance of high-sensitivity cardiac troponin T (hs-cTnT) varies depending on presenting symptoms in patients with suspected acute coronary syndrome (ACS).

METHODS

We compared performance measures of hs-cTnT among patients admitted to the emergency department with typical chest pain (angina), dyspnea, and atypical symptoms and assessed outcomes by leading presenting symptoms.

RESULTS

A total of 658 patients suspected of ACS and presenting with typical chest pain (n = 241, 36.6%), dyspnea (n = 142, 21.6%), or atypical symptoms (n = 275, 41.8%) were included. Diagnostic accuracy of hs-cTnT on admission was higher among patients with typical chest pain compared to those with atypical symptoms [area under the curve (AUC) 0.823 vs AUC 0.776 vs AUC 0.705, P > 0.05 and P = 0.04]. Absolute concentration changes within 6 h improved accuracy among all subgroups, with the smallest added benefit in typical chest pain and dyspnea (ΔAUC, 0.078; P = 0.02 and 0.05, P > 0.05). During 1-year follow-up, dyspnea was associated with a higher risk of death (hazard ratio, 2.36; 95% CI, 1.26–4.43, P = 0.008) and death/AMI (hazard ratio, 2.23; 95% CI, 1.21–4.11, P = 0.01) compared to typical chest pain. Optimal discriminating values for hs-cTnT were higher among patients presenting with dyspnea compared to those with typical chest pain (91.2 vs 14.1 ng/L, P < 0.001).

CONCLUSION

The diagnostic performance of hs-cTnT in patients with suspected ACS depends on the leading presenting symptom. Patients admitted with dyspnea represent a high-risk cohort in which the diagnosis of ACS is less frequent and with inferior performance of serial hs-cTnT measurements. Higher hs-cTnT cutoffs at baseline and absolute changes after 6 h help to identify non-STEMI (ST segment elevation myocardial infarction) in this population.
Book Reviews
Authors: Senff Sarah , Lazaroo Natalie , Glass Penelope
Published: March 2015

Staging Social Justice: Collaborating to Create Activist Theatre, edited by Norma Bowles and Daniel-Raymond Nadon (2013) Carbondale, IL: Southern Illinois University Press, 328 pp. ISBN 0 8093 3238 8, p/bk, $35.00.

‘We’re People Who Do Shows’: Back to Back Theatre – Performance Politics Visibility, edited by Helena Grehan and Peter Eckersall (2013) Aberystwyth: Performance Research Books, ISBN 9 7819 0649 9037, 288 pp., p/bk, $86

Theatre of Good Intentions: Challenges and Hopes for Theatre and Social Change by Dani Snyder-Young (2013) Palgrave Macmillan, New York, ISBN 9 7811 3729 3022, Ebook, US$78.85
A collaborative study on social transformation: Educational Volunteers Foundation of Turkey and Oluşum Drama Institute
Authors: Özbek Gökçen , Aslan Naci , Söken Ali
Published: March 2015

Educational Volunteers Foundation of Turkey (TEGV) was founded with the aim of supporting the primary education provided by the government. One of the main objectives of TEGV is to create and implement educational programmes and extracurricular activities for socially/economically disadvantaged children, so they can acquire skills, knowledge and attitudes to support their development while learning to resist any kind of discrimination. In 2003, considering the aims of the foundation and the outcomes of the drama education, a collaboration was established between TEGV and Oluşum Drama Institute (ODI). A ten-week drama programme was developed with the aim of helping children to acquire basic personal skills such as self-confidence, empathy, self-development and creativity. This ongoing programme is being assessed at the end of every term, and revision is being conducted according to the results and the feedback. The results gathered from different locations reveal that the drama programme is successfully reaching its goals.
Education through theatre: Typologies of Science Theatre
Authors: Chemi Tatiana , Kastberg Peter
Published: March 2015

Theatre, with its borderline praxis between entertainment and reflection, offers a precious opportunity to deliver difficult scientific or social issues within scientific dilemmas to all kinds of target groups, such as youngsters. But what makes Science Theatre an obvious choice for communicating natural science issues and dilemmas? What lies beneath this label? Is this concept at all new? The research agenda of the present article is centred on exploring the multifaceted phenomenon of Science Theatre. As a unifying device, we propose to approach Science Theatre from the point of view of communication theory. This allows us to transform the amorphous matter of the wide variety of Science Theatre performances into analytically manageable prototypes, as well as providing a robust base for exploring the affordances of different types of Science Theatre.
Public-Private Partnership as a Path to Affordable Healthcare in Emerging Markets
Authors: Chou Jacquelyn W. , Lakdawalla Darius N. , Vanderpuye-Orgle Jacqueline
Published: March 2015

The BRICS countries (Brazil, Russia, India, China, and South Africa) have experienced tremendous economic and health gains in recent decades. Two of the major health challenges faced by the BRICS and other low and middle income countries are decreasing inequity in health outcomes and increasing affordability of health insurance. One fiscally sustainable option for the BRICS governments is a public subsidy system for private health insurance plans. This essay lays out the potential applicability and impacts of public subsidies for private health insurance plans, as well as opportunities and challenges for implementation, in the BRICS countries. Overall, providing public subsidies rather than health insurance would enable the BRICS governments to avoid the open-ended financial liabilities that have plagued advanced economies, while still expanding access to health insurance and encouraging the develoment of a robust private health insurance market. We conclude by suggesting an array of pilot programs that could serve as the seeds for publicly subsidized health insurance schemes within the BRICS markets.
Ein vereinfachter optischer Aufbau für den Autofokus eines Mikroskops mittels einer verstellbaren Linse
Authors: Müller Thomas , Pösch Andreas , Reithmeier Eduard
Published: March 2015

Bei der Inspektion von Oberflächen mittels Lichtmikroskopie muss auf die korrekte Bauteilpositionierung geachtet werden, da Mikroskope meist nur einen sehr geringen Schärfentiefebereich aufweisen. Bauteile mit gekrümmten Oberflächen erfordern stets eine Fokussierung, damit sich scharfe Abbildungen ergeben. Dieser Artikel stellt eine vereinfachte Möglichkeit zur Fokussierung bei mikroskopischen Messungen dar. Der vorgeschlagene Aufbau benötigt lediglich ein Mikroskopobjektiv, eine Linse mit konstanter Brennweite und eine Linse mit variabler Brennweite. Durch diesen Aufbau lässt sich die axiale Fokusposition gezielt verändern. In diesem Beitrag wird beschrieben, wie sich durch korrekte Platzierung der Komponenten ein konstanter Abbildungsmaßstab und Gesichtsfeld bei der axialen Fokusverschiebung erreichen lassen. Außerdem werden verschiedene Algorithmen zur automatisierten Fokussierung in Zusammenhang mit dem vorgeschlagenen Aufbau an mikrostrukturierten Oberflächen evaluiert.
Zur Theorie der Vielfachstreuung geladener Teilchen
Authors: Sauter F. , Wanke H.
Published: March 2015

Durch strenge Umwandlung der beim Problem der Vielfachstreuung auftretenden Integralgleichung in eine Differentialgleichung läßt sich ein konsequentes Näherungsverfahren zur Ermittlung der Winkelabhängigkeit der Streuintensität angeben. Dieses Verfahren führt in erster Näherung zu einer Lösungsfunktion, aus der sich ein wohlbestimmter Wert für das mittlere Quadrat des Streuwinkels ergibt. Zahlenmäßig liegt er in der gleichen Größenordnung wie der Ausdruck, zu dem man aus der Molièreschen Theorie kommt, wenn man dort die Formel für die Streuintensität nach dem ersten Glied mit der Gauß-Funktion abbricht. Es wird darauf hingewiesen, daß die Art der Abspaltung dieses ersten Gliedes bei Molière weitgehend willkürlich ist, während das hier durchgeführte Verfahren zur Ermittlung der Größe ϑ̅2 völlig zwangsläufig erscheint.
Über die Erhaltungssätze der Physik
Authors: Jordan Pascual
Published: March 2015

Die Arbeit bemüht sich, eine Verbindung herzustellen zwischen dem neuerdings von verschiedenen Verfassern befürworteten Versuch, über die fünfdimensional-projektive Relativitätstheorie hinaus eine sechsdimensionale Zusammenfassung der physikalischen Grundgesetze anzubahnen, und der aus empirischen Tatsachen entstandenen Vermutung, daß ein bislang noch unberücksichtigt gebliebener Erhaltungssatz für die „Neutron-Ladung“ (Wigner) existiert. Beides scheint darauf hinzuweisen, daß die Invarianzgruppe der physikalischen Grundgesetze umfassender ist, als bislang angenommen wurde. Eine bestimmte Präzisierung dieser Vermutung wird erläutert.
Turbulenz und Temperatur der Sonnenchromosphäre
Authors: Unsöld A.
Published: March 2015

Es wird gezeigt, daß in der Sonnenatmosphäre turbulente Strömungen bestehen, deren Geschwindigkeit von ∼ 2 km/sec in der umkehrenden Schicht auf ∼ 15 km/sec in der mittleren und höheren Chromosphäre zunimmt. Die Temperatur (verstanden als Anregungstemperatur kleiner Termdifferenzen, kinetische und Elektronentemperatur) der Chromosphäre ergibt sich zu ∼ 3800° K. Redmans Messungen von Profilen chromosphärischer Linien, aus denen er auf eine Temperatur von ∼ 30 000° geschlossen hatte, können auch anders interpretiert werden. — Soweit die Mach-Zahl der solaren Turbulenz die Eins überschreitet, handelt es sich nicht mehr um ein rein hydrodynamisches Phänomen; es setzt vielmehr die Bildung fadenartiger Protuberanzen ein, die offenbar geringere Energiedissipation aufweisen. Dieses plasmaphysikalische Phänomen dürfte allgemeinere astrophysikalische Bedeutung haben.
Über die Störstellen- und Eigenhalbleitung intermetallischer Verbindungen
Authors: Justi E. , Lautz G.
Published: March 2015

Im Gegensatz zu den allgemein bekannten Widerstandsminima bei den Überstrukturen der Edelmetallegierungen zeigen sich im System Cd—Sb bei den intermetallischen Verbindungen sehr hohe Maxima des elektrischen Widerstandes. Dieser Effekt wird in der vorliegenden Arbeit hinsichtlich seiner Strukturabhängigkeit experimentell und theoretisch näher untersucht. Dabei ergibt sich, daß beim CdSb die Brillouin-Zonen mit Elektronen gerade voll aufgefüllt sind, so daß reinstes und stöchiometrisch zusammengesetztes CdSb als echter Eigenhalbleiter aufgefaßt werden kann.

Durch geringe Zusätze anderer Metalle zu CdSb können Störstellenhalbleiter erzeugt werden, deren Widerstandsverhalten bei Zimmertemperatur in Abhängigkeit von der Zusammensetzung näher untersucht wird. Die möglichen Fälle einer Überschuß- und Mangelhalbleitung werden im Anschluß an die theoretischen Erkenntnisse über die Brillouin-Zonenstruktur eingehend diskutiert.

Dieser vollständig neue Halbleitertyp zeigt eine Reihe besonderer Eigenschaften, die ihn von den bisher bekannten Halbleiterarten unterscheiden. So zeigt die elektrische Leitfähigkeit am Schmelzpunkt eine sprunghafte Verbesserung, wie sie im Rahmen unserer theoretischen Deutung zu erwarten ist. Durch einen Überschuß der einen oder anderen Metallkomponente wird beim CdSb in jedem Fall ein Überschußleiter erzeugt.

Die theoretische Deutung aller Effekte ist nur unter besonderen Annahmen über die bisher nicht ausreichend bekannte Kristallstruktur möglich. Da die erforderlichen Voraussetzungen mit den bekannten Strukturuntersuchungen verträglich sind und zudem die beobachteten elektrischen Anomalien erklären können, ist an ihrer grundsätzlichen Gültigkeit nicht zu zweifeln.

Schließlich wird in der vorliegenden Arbeit auf die Effekte beim CdSb hingewiesen, die sich durch das Auftreten einer metastabilen Verbindung Cd3Sb2 ergeben. Je nach der Abkühlgeschwindigkeit der geschmolzenen Legierungen erhält man einen verschieden hohen Anteil des Cd3Sb2 mit heterogen ausgeschiedenem Sb. Aus diesem Grunde werden für die Herstellung der Legierungen besondere Methoden angegeben.
Eine Ionenquelle
Authors: Kamke Detlef
Published: March 2015

Es wird eine Ionenquelle für Gasionen beschrieben, mit welcher 700 µA Wasserstoff-Ionenstrom von 20 keV Energie bei einem Leistungsaufwand von 90 Watt erzielt wurden.
Über gittertheoretische Berechnung der Energie von Störstellen in einfachen Ionenkristallen
Authors: Brauer Peter
Published: March 2015

Die Gittertheorie der einfachen Ionenkristalle wird auf Störstellen, die durch Fehlbau an Gitterpunkten entstehen, angewandt. Unter Benutzung grundlegender Ergebnisse von Mott und Littleton werden die Verzerrung und die Polarisation von Steinsalzgittern berechnet, die durch Einbau eines Fremdions auf einem Gitterplatz oder Ausbau eines Gitterions entstehen. Die durch Verzerrung und Polarisation des Kristalls geänderte Energie des Ions am fraglichen Gitterplatz und die daraus folgende Ausbauarbeit wird berechnet. Auf Anwendungen wird hingewiesen. Das Problem des Einbaus des Tl+ in NaCl und KCl wird ausführlich behandelt mit dem Resultat, daß Tl+-Ionen freiwillig in KCl, nicht aber in NaCl eingebaut werden, was mit dem experimentellen Ergebnis von Pringsheim u. a. in Übereinstimmung ist.
Zur Begründung der Masse-Ladungs-Renormalisierung und ihre Anwendung auf das Maxwell-Feld
Authors: Salecker H.
Published: March 2015

Im ersten Teil wird am Beispiel der Quantenelektrodynamik gezeigt, daß die in der Quantentheorie der Wellenfelder zur Umgehung der bekannten Divergenzschwierigkeiten oft benutzten Renormalisierungsvorschriften von Massen und Kopplungskonstanten zwangsläufig aus der vorhandenen Theorie folgen. Diese Vorschriften müssen vor jedem Vergleich mit der Erfahrung durchgeführt werden, gleichgültig, ob die Theorie Divergenzen enthält oder nicht. Dies ergibt sich, wenn man die physikalische Bedeutung der einzelnen Bestandteile der vorkommenden Massen und Kopplungskonstanten sowie die durch die Benutzung der Störungsrechnung bedingten Erfordernisse genau beachtet. Hierbei wird eine ganz entsprechende Behandlung der Lichtquantenselbstenergie nahegelegt, die im zweiten Teil durchgeführt wird. Dabei wird die (unbeobachtbare) Ruhmasse des kraftfreien Lichtquants, die bisher ebenso wie die Ruhmasse des beobachtbaren Lichtquants gleich 0 gesetzt wurde, unbestimmt gelassen und nur verlangt, daß die Ruhmasse des beobachtbaren Lichtquants verschwindet. Dann hat man bei der Lichtquantenselbstenergie ganz entsprechend wie bei der Selbstenergie des Elektrons vorzugehen. Hierbei bleibt die Eichinvarianz der allein beobachtbaren Theorie mit Wechselwirkung erhalten, während die wechselwirkungsfreie Theorie nicht eichinvariant ist. Bei dieser Behandlung werden verschiedene Schwierigkeiten bei der Quantisierung und der Vakuumpolarisation (Lichtquantenselbstenergie) vermieden, die durch die bisher immer verlangte Eichinvarianz der kraftfreien Theorie bedingt waren. Das Maxwell-Feld läßt sich nun genau so renormalisieren wie etwa das Elektron-Positron-Feld.
Die Einzelstreuung von Elektronen an Atomkernen
Authors: Kinzinger E. , Bothe W.
Published: March 2015

Es werden Messungen der Einzelstreuung von 245-keV-Elektronen in Metallfolien beschrieben. Die Elektronenstrahlen wurden mit einem Bandgenerator erzeugt. Der Einfluß der Vielfachstreuung wurde experimentell und theoretisch diskutiert. Die Einzelstreumessungen wurden durchgeführt als Relativmessungen von Ni, Ag und Au zu Al, als Messung der Winkelverteilung für Al und als Absolutmessung des Streuquerschnittes von Al für den Streuwinkel 50°. Ergebnisse: Für Al werden die Mottschen Absolutwerte des Streuquerschnittes über den Winkelbereich ϑ = 30° - 150° bestätigt, für die höheren Elemente ebenso für ϑ < 70°. Für die höheren Elemente und für ϑ > 70° sind die gemessenen Streuquerschnitte kleiner als die theoretischen. Die Abweichungen nehmen mit ϑ und Z zu und erreichen 37% für Au bei 150°. Die möglichen Ursachen für diese Abweichungen werden diskutiert.
Die Lebensdauer isomerer Kerne
Authors: Stech Berthold
Published: March 2015

Auf der Grundlage des Einteilchenmodells der Kerne werden Formeln für die elektrische und magnetische Multipolstrahlung eines Nukleons abgeleitet und die vorkommenden Integrale berechnet. Die Zuordnung der Terme nach dem Einteilchenmodell mit starker Spin-Bahn-Kopplung führt insbesondere bei den magnetischen 24-Pol-Übergängen (g9/2 ↔ P1/2; h11/2 ↔ d3/2; i13/2 ↔ f5/2)zu einer mit den Experimenten übereinstimmenden Energieabhängigkeit der Übergangswahrscheinlichkeit. Die theoretischen Übergangswahrscheinlichkeiten sind jedoch um einen nahezu konstanten Faktor (≈ 30) zu groß.
Über die Ionisations- und Rekombinationsprozesse in einem Plasma und die Ionisationsformel der Sonnenkorona
Authors: Elwert Gerhard
Published: March 2015

Befindet sich ein Plasma nicht im thermodynamischen Gleichgewicht, so ist zur Berechnung seines Ionisationsgrades die Kenntnis der Zahl der Elementarprozesse der Ionisation und Rekombination erforderlich. Es sind dies einerseits die Photoionisation und die Ionisation durch Elektronenstöße, andererseits die Rekombination unter Aussendung von Lichtquanten und durch Dreierstöße. Für jeden dieser vier Prozesse werden Formeln angegeben. Die Stoßionisationen und Photorekombinationen werden genauer diskutiert. Durch Gleichsetzung ihrer Zahl ergibt sich eine verschärfte Ionisationsformel für die Sonnenkorona, aus der man mit Hilfe des bekannten Intensitätsverhältnisses der grünen und roten Koronalinie die Temperatur der Sonnenkorona bestimmen kann. Die Genauigkeit dieser Temperaturbestimmung wird abgeschätzt.
Vergleich solarer Erscheinungen mit der Veränderlichkeit von Sternen in Gasnebeln
Authors: Binge Hans-Jost
Published: March 2015

Die vorliegenden Untersuchungen über die RW Aurigae-Veränderlichen machen es wahrscheinlich, daß diese Sterne einen sonnenähnlichen Charakter haben. Dadurch liegt es nahe, die Besonderheiten dieser Sterne durch eine der Fleckenaktivität der Sonne analoge, aber viel stärkere Erscheinung zu erklären. Es wird in dieser Arbeit gezeigt, daß die Beobachtungen sich dadurch gut verstehen lassen.

Im Anschluß daran wird versucht, die Aktivität der Sonne durch äußere Einflüsse, wie sie für die RW Aurigae-Sterne angenommen werden, auf mechanischem Wege zu erklären.
Die Rolle der Ausstrahlungsbedingung bei komplexer Wellenzahl und ihre Bedeutung für das Problem der Oberflächenwelle
Authors: Haug Albert
Published: March 2015

Es wird gezeigt, daß die Sommerfeldsche Ausstrahlungsbedingung die Eindeutigkeit der Lösungen der Wellengleichung Δu + k2u = 0 im Gesamtraume nicht nur bei reeller, sondern auch bei komplexer Wellenzahl k gewährleistet. Der Eindeutigkeitsbeweis läßt sich unter gewissen Voraussetzungen auf zwei Halbräume erweitern. Schließlich folgt daraus, daß die Sommerfeldsche Oberflächenwelle mit der Ausstrahlungsbedingung nicht im Widerspruch steht.
Der Einfluß von Zweierstößen auf die molekulare Gasströmung
Authors: Hiby J. W. , Pahl M.
Published: March 2015

Die im I. Teil entwickelte Näherungsmethode, die Kinetik relativ seltener Zweierstöße in molekularen Strömungen zu behandeln, wird in geeigneter Abwandlung auf weitere Formen von Strömungswiderständen ausgedehnt: Spaltkanal zwischen ebenen, parallelen Platten, kreisrunde Lochblende, kurze Röhre sowie poröse Medien. Der Leitwert F eines Spaltkanals nimmt (im molekularen Strömungsbereich) mit zunehmendem Gasdruck p viel stärker ab als der einer langen Röhre; dagegen ergibt sich bei der Lochblende eine lineare Zunahme von F mit p. Beide Ergebnisse stimmen mit Messungen von Gaede14 bzw. Knudsen30 überein. Bei kurzen Röhren und bei geknickten Röhren mit kurzer Teilstücklänge ist stets lineare Druckabhängigkeit für F gegeben; Vorzeichen und Betrag des Proportionalitätsfaktors hängen jedoch in empfindlicher Weise vom Verhältnis Röhrenlänge/Durchmesser ab. Die voneinander abweichenden Meßwerte verschiedener Autoren für diesen Proportionalitätsfaktor bei der molekularen Durchströmung von porösen Medien lassen sich demnach auf Unterschiede in der Porenstruktur zurückführen.
Die Bindungsenergien und Massen der Atomkerne A = 17 bis A = 32
Authors: Cappeller U.
Published: March 2015

Aus dem derzeit vorliegenden Beobachtungsmaterial über die Energietönung von Kernreaktionen werden in Anlehnung an die Ewaldsche Massenleiter die Bindungsenergien und Massen der Atomkerne A = 17 bis A = 32 neu berechnet.