bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk factor analysis for pneumococcal meningitis in adults with invasive pneumococcal infection
Authors: BURCKHARDT I. , BURCKHARDT F. , VAN DER LINDEN M. , HEEG C. , REINERT R. R. 
Published: January 2010

SUMMARYPneumococcal meningitis is a subgroup of invasive pneumococcal disease with a case-fatality rate of up to 30% and long-term sequelae in more than 50% of cases in adults in developed countries. We aimed to determine risk factors for this particular form of pneumococcal disease. We conducted a prospective population-based laboratory study of invasive pneumococcal disease in adults in North-Rhine-Westphalia, Germany from February 2001 to August 2006. All isolates underwent serotyping and susceptibility testing at the National Reference Centre for Streptococci in Aachen, Germany. Data were analysed using multiple linear regression. A total of 1043 isolates from bacteraemia and 131 isolates from meningitis were included into the study. Serotype 23F and being female were independent risk factors for pneumococcal meningitis. Being ⩾60 years and serotype 1 were associated with a reduced odds ratio. Season, penicillin and macrolide resistance were not statistically associated with CNS involvement.
Sumset and Inverse Sumset Theory for Shannon Entropy
Authors: TAO TERENCE 
Published: January 2010

Let G = (G, +) be an additive group. The sumset theory of Plünnecke and Ruzsa gives several relations between the size of sumsets A + B of finite sets A, B, and related objects such as iterated sumsets kA and difference sets A − B, while the inverse sumset theory of Freiman, Ruzsa, and others characterizes those finite sets A for which A + A is small. In this paper we establish analogous results in which the finite set A ⊂ G is replaced by a discrete random variable X taking values in G, and the cardinality |A| is replaced by the Shannon entropy H(X). In particular, we classify those random variables X which have small doubling in the sense that H(X1 + X2) = H(X) + O(1) when X1, X2 are independent copies of X, by showing that they factorize as X = U + Z, where U is uniformly distributed on a coset progression of bounded rank, and H(Z) = O(1).When G is torsion-free, we also establish the sharp lower bound $\Ent(X+X) \geq \Ent(X) + \frac{1}{2} \log 2 - o(1)$, where o(1) goes to zero as H(X) → ∞.
REAL THETA CHARACTERISTICS AND AUTOMORPHISMS OF A REAL CURVE
Authors: BISWAS INDRANIL , GADGIL SIDDHARTHA 
Published: January 2010

AbstractLet X be a geometrically irreducible smooth projective curve defined over ℝ, of genus at least 2, that admits a nontrivial automorphism, σ. Assume that X does not have any real points. Let τ be the antiholomorphic involution of the complexification xℂ of X. We show that if the action of σ on the set 𝒮(X) of all real theta characteristics of X is trivial, then the order of σ is even, say 2k, and the automorphism $\tau \circ \widehat {\sigma }^k$ of Xℂ has a fixed point, where $\widehat {\sigma }^k$ is the automorphism of X×ℝℂ defined by σ. We then show that there exists X with a real point and admitting a nontrivial automorphism σ, such that the action of σ on 𝒮(X) is trivial, while X/〈σ〉≠ℙ1ℝ. We also give an example of X with no real points and admitting a nontrivial automorphism σ, such that the automorphism $\tau \circ \widehat {\sigma }^k$ has a fixed point, the action of σ on 𝒮(X) is trivial, and X/〈σ〉≠ℙ1ℝ.
VOCAL RIPIENISTS AND J. S. BACH'S MASS IN B MINOR
Authors: PARROTT ANDREW 
Published: January 2010

ABSTRACTDespite its apparent lack of an early performance history, the Mass in B minor proves fertile ground for an investigation of J. S. Bach's expectations of choral performance, not merely on account of the work's sheer number of choruses but because of their individual origins and stylistic diversity. By systematically exploring each movement with an understanding of how eighteenth-century vocal concertists and ripienists traditionally functioned, we may be better placed to assess whether or not this ‘great’ work carries any implications of vocal forces that are exceptionally ‘great’ (numerically) in Bach's terms. Key underlying strands of argument concerning the size and distribution of Bach's choir are reviewed in an Appendix, alongside newly introduced items of evidence.
Is conventional agricultural research fit for the purpose of supporting ecological agriculture? A case study of an attempted transition in Sweden
Authors: Eksvärd Karin 
Published: January 2010

AbstractIn order to increase ecological horticulture in Sweden, it is necessary to increase productivity while reducing working hours. To improve the relevance of research results as a base for such transitions, a Participatory Learning and Action Research (PLAR) group was added to a conventional research project that aimed to find options for using green manure as a multifunctional tool in vegetable production. The project consisted of four work packages looking at different aspects of a system of interest defined by researchers. The PLAR group sought to evaluate the agronomic outcome of the conventional research outputs but came to add qualitative experience of using the different manuring methods tried. The article reports on the evaluation of the PLAR activities as well as on issues of cooperation and understanding The difficulties and constrains that arose revealed the limitations of conventional research as a means for supporting ecological horticulture transitions, but using PLAR as an ‘add on method’ is also shown to be inadequate for helping producers effect the transitions required. Discussion on the robustness of the data generated and the stability of the approach show the importance of using approaches that are fit for practice when extending research to develop ecological horticulture to include participation with practitioners. Moving from conventional research approaches to trans-disciplinary approaches is not easy and includes the need to relate the contextual knowledge of farmers to the abstract knowledge of scientists.
Allocating Conservation Resources Under The Endangered Species Act
Authors: Langpap Christian , Kerkvliet Joe 
Published: January 2010

AbstractWe explore the allocation of recovery funds to species listed under the Endangered Species Act. We simulate outcomes from allocations based on the U.S. Fish and Wildlife Service's priority rankings and on rankings used in U.S. states' Wildlife Action Plans developed under the Congressional Wildlife Conservation and Restoration Program. We find that these criteria yield modest improvements over the FWS's current allocations and that documented inconsistencies in these allocations do not have a detrimental impact on the effectiveness of conservation spending. We also find that alternative policy goals—promoting recovery or preventing extinction—imply a tradeoff between increasing the number of Improving species and reducing the number of Extinct species of roughly 2:1.
Developing Variable Unit‐Structure Premium Rate Differentials in Crop Insurance
Authors: Knight Thomas O. , Coble Keith H. , Goodwin Barry K. , Rejesus Roderick M. , Seo Sangtaek 
Published: January 2010

AbstractFederal crop insurance programs offer producers the option of insuring farm units individually or as an aggregate unit. Existing programs offer a fixed 10% discount for most growers taking coverage at the aggregate level. This article describes an analysis of risk changes when units are aggregated. The methods described here, which base unit aggregation discounts on observable farm characteristics, are approved for implementation into the Federal Crop Insurance Program.
Are Intraday Volume and Volatility U‐Shaped After Accounting for Public Information?
Authors: Eaves James , Williams Jeffrey 
Published: January 2010

AbstractNo matter how pronounced intraday patterns may appear, it is difficult to account for cross‐correlations among related assets when those assets trade continuously and simultaneously. Futures contracts are auctioned periodically and sequentially on the Tokyo Grain Exchange (TGE). Even though intraday TGE volume is U‐shaped, intraday volatility is closer to L‐shaped. After accounting for the public information in immediately preceding auctions for the same commodity, for earlier trading in other commodities, and for trading on overseas markets open overnight in Tokyo, the intraday patterns are effectively flat. Thus, the timing of privately informed traders cannot be the source of intraday patterns.
Meat Meets Meta: A Quantitative Review of the Price Elasticity of Meat
Authors: Gallet Craig A. 
Published: January 2010

AbstractThe price elasticity of meat has been estimated in numerous studies that utilize a variety of disparate modeling procedures. In light of differences in the literature, a meta‐analysis is performed to assess the sensitivity of the meat price elasticity to a number of characteristics, including the type of meat, specification of demand, nature of data, estimation method, characteristics of the publication outlet, and location of demand. The results from estimating linear and Box‐Cox meta‐regressions, coupled with different panel data treatments, reveal that these characteristics have differing influence on the reported price elasticity.
Technology Adoption and Technical Efficiency: Organic and Conventional Dairy Farms in the United States
Authors: Mayen Carlos D. , Balagtas Joseph V. , Alexander Corinne E. 
Published: January 2010

AbstractWe compare productivity and technical efficiency of organic and conventional dairy farms in the United States. We address self‐selection into organic farming by using propensity score matching and explicitly test the hypothesis that organic and conventional farms employ a single, homogeneous technology. Utilizing the 2005 Agricultural Resource Management Survey on Dairy Costs and Returns Report (ARMS) data, we reject the homogeneous technology hypothesis and find that the organic dairy technology is approximately 13% less productive. However, we find little difference in technical efficiency between organic and conventional farms when technical efficiency is measured against the appropriate technology.
Revisiting the Evaluation of Robust Regression Techniques for Crop Yield Data Detrending
Authors: Finger Robert 
Published: January 2010

AbstractUsing a Monte Carlo experiment, the performance of the ordinary least squares (OLS) and the MM‐estimator, a robust regression technique, is compared in an application of crop yield detrending. Assuming symmetric as well as skewed crop yield distributions, we show that the MM‐estimator performs similarly to OLS for uncontaminated time series of crop yield data, and clearly outperforms OLS for outlier‐contaminated samples. In contrast to earlier studies, our analysis suggests that robust regression techniques, such as the MM‐estimator, should be reconsidered for detrending crop yield data.
The Role of Theoretical Restrictions in Forecasting with Inverse Demand Models
Authors: Klaiber H. Allen , Holt Matthew T. 
Published: January 2010

AbstractIn recent years, the theoretical restrictions of consumer demand have been examined in post‐sample forecasting exercises. However, this work has uniformly ignored associated curvature restrictions. In this paper we evaluate a series of Normalized Quadratic Inverse Demand System (NQIDS) specifications by using rolling windows and generating one‐ to four‐step ahead forecasts. Data for eleven categories of South Atlantic fish spanning 1980 through 2001 are used in estimation. In addition to the NQIDS, we also examine the forecasting performance of a Cobb–Douglas model with autoregressive errors. We find that the best predictions are achieved using a composite forecast.
Apolipoproteins in the discrimination of atherosclerotic burden and cardiac function in patients with stable coronary artery disease
Authors: Patel Jeetesh V. , Abraheem Abraheem , Creamer John , Gunning Mark , Hughes Elizabeth A. , Lip Gregory Y.H. 
Published: January 2010

AimsTo compare the performance of apolipoproteins (Apo) and oxidized LDL against routine clinical lipid profiles in the discrimination of atherosclerotic burden and cardiac function in stable coronary artery disease (CAD) patients.Methods and resultsUsing a cross‐sectional approach, we measured oxidized LDL, Apo AI and B in 199 patients (34–81 years) with stable symptomatic CAD. The discrimination of (i) atherosclerotic burden (coronary atheroma scores, the number of diseased coronary vessels), and (ii) cardiac function [NYHA classification, left‐ventricular systolic dysfunction (LVSD)] were judged using receiver operating characteristic (ROC) curves. The ratio of Apo AI to B was correlated to oxidized LDL (Spearman, r = 0.37, P < 0.001); however, oxidized LDL was unrelated to measures of cardiac function or CAD severity. Concentrations of Apo AI decreased from 1.38 to 1.20 g/L with increasing atheroma scores (P = 0.02), while triglyceride levels increased from 1.50 to 2.23 mmol/L (P = 0.016). High‐density lipoprotein (HDL) cholesterol and Apo AI levels were higher among those with heart failure (P = 0.002), and increased ordinally with NYHA class (P = 0.005). On ROC analysis, reduced levels of Apo AI and HDL cholesterol were discriminators for patients in the upper quartile for atheroma score (P < 0.004). Raised indices of HDL were associated with heart failure (P < 0.002).ConclusionApo AI levels are a consistent discriminator of atherosclerotic burden among patients with stable CAD. However, heart failure presents an element of confounding in the diagnostic and prognostic utility of Apo monitoring among these patients.
Sutureless Aortic Valve Replacement via Partial Sternotomy
Authors: Martens Sven , Zierer Andreas , Ploss Anja , Sirat Sami , Miskovic Aleksandra , Moritz Anton , Doss Mirko 
Published: January 2010

Objective For elderly patients with symptomatic aortic valve stenosis, aortic valve replacement with tissue valves is still the treatment of choice. Stentless valves were introduced to clinical practice for better hemodynamic features as compared with stented tissue valves. However, the implantation is more complex and time demanding, especially in minimal invasive aortic valve replacement. We present our clinical data on 22 patients having received a sutureless ATS 3f Enable aortic bioprosthesis via partial upper sternotomy. Methods The procedure was performed using CPB with cardioplegic arrest. After resection of the stenotic aortic valve and debridement of the annulus, the valve was inserted and released. Mean age was 79 years, and mean logistic Euroscore was 13. Subvalvular myectomy was performed in two patients. Prosthetic valve sizes were 19 mm (n = 1), 21 mm (n = 7), 23 mm (n = 6), 25 mm (n = 6), and 27 mm (n = 2). Results Implantation of the valve required 10 ± 6 minutes. Cardiopulmonary bypass and aortic crossclamp time were 87 ± 16 and 55 ± 11 minutes, respectively. Early mortality (<90 days) was 9% (2 patients). No paravalvular leakage was detected intraoperatively or in follow-up echocardiography. The mean transvalvular gradients were 9 ± 6 mm Hg at discharge and 8 ± 2 mm Hg at 1-year follow-up. Conclusions Sutureless valve implantation via partial sternotomy is feasible and safe with the ATS 3f Enable bioprosthesis. Reduction of cardiopulmonary bypass and aortic crossclamp time seems possible with increasing experience. Hemodynamic data are very promising with low gradients at discharge and after 12 month. Sutureless valve implantation via minimal invasive access may be an alternative treatment option for elderly patients with high comorbidity.
Acute Feasibility Study of a Novel Device for the Treatment of Mitral Regurgitation in a Normal Canine Model
Authors: Takaseya Tohru , Fumoto Hideyuki , Saraiva Roberto M. , Shiose Akira , Arakawa Yoko , Park Margaret , Rao Santosh , Dessoffy Raymond , Kramer Larry D. , Juravic Mark , Lombardi Pierluca , Fukamachi Kiyotaka 
Published: January 2010

Objective The purpose of this study was to evaluate the implantability of a novel epicardial mitral annuloplasty device and its ability to reduce the septal-lateral (S-L) dimension of the mitral annulus. Methods The devices were implanted on the beating heart in 2 healthy dogs (the 24-mm long device in dog A and the 27-mm and 24-mm standard devices in dog B) by sliding the anterior arm onto the floor of the transverse sinus and positioning the posterior arm just apical to the atrioventricular groove on the left ventricular posterolateral wall. The devices were secured with titanium helical tacks driven through the device into the ventricular wall. Two-dimensional epicardial echocardiograms were performed before and after device implantation to evaluate the degree of mitral regurgitation (MR) and the S-L dimension. Results Device implantation was uneventful, taking only ~30 seconds to deploy. MR (1 +) in both dogs at baseline was reduced to zero after implant. The reductions in S-L dimension in systole for the 24-mm device were 7.5% in dog A and 30.5% in dog B. For the 27-mm device in dog B, S-L reduction in systole was 29.9%. The leaflet coaptation length was increased in both cases. Conclusions The new device was effective in reducing S-L dimension and 1 + MR without requiring the use of cardiopulmonary bypass. We are currently evaluating this device for the treatment of MR in a rapid-pacing canine heart failure model.
Comparison of Minithoracotomy versus Sternotomy in 304 Consecutive Tricuspid Valve Operations
Authors: Lee Teng C. , Desai Bhargavi S. , Milano Carmelo , Jaggers James , Glower Donald D. 
Published: January 2010

Objective The relative outcomes of sternotomy versus thoracotomy for tricuspid valve operation were examined over a 22-year period. Methods Three hundred four consecutive patients undergoing tricuspid valve operation using right minithoracotomy (THORC group; n = 124) versus median sternotomy (STERN group; n = 180) between 1985 and 2007 were retrospectively analyzed. Minithoracotomy used a 6-cm incision with femoral venous cannulation and augmented venous return. Sternotomy patients undergoing aortic valve, coronary bypass, or other procedure not feasible through a right minithoracotomy were excluded. Results Both groups were similar except that STERN patients had an earlier operative year. Combined mitral and tricuspid valve operation was performed in 70% (214/304) of patients. The tricuspid valve was repaired in 59% (180/304) of patients. Previous sternotomy was present in 56% (171/304) of patients. The mean cardiopulmonary bypass times were longer in the THORC group (216 vs. 167 minutes, <P < 0.0001). THORC was associated with a lower 30-day mortality (2% vs. 11%, P = 0.007), less atrial fibrillation (18% vs. 34%, P = 0.0025), less renal failure (3% vs. 11%, P = 0.016), and shorter length of stay (11 vs. 15 days, P = 0.012), although these differences were less apparent in more recent years. Stroke (3% vs. 2%, P = 0.72), respiratory failure (7% vs. 31%, P = 0.06), and infection rates (11% vs. 16%, P = 0.25) were similar. Five-year survival was also similar (63% vs. 64%, P = 0.84). Conclusions Given the limitations of a large, retrospective experience, minithoracotomy versus sternotomy is associated with low short-term morbidity and mortality, with advantages of avoiding sternotomy and minimizing mediastinal dissection in an otherwise high-risk group of patients.
On the stability and control of unicycles
Authors: Sharp Robin S. 
Published: January 2010

A mathematical model of a unicycle and rider, with a uniquely realistic tyre force and moment representation, is set up with the aid of multibody modelling software. The rider’s upper body is joined to the lower body through a spherical joint, so that wheel, yaw, pitch and roll torques are available for control. The rider’s bandwidth is restricted by low-pass filters. The linear equations describing small perturbations from a straight-running state are shown, which equations derive from a parallel derivation yielding the same eigenvalues as obtained from the first method. A nonlinear simulation model and the linear model for small perturbations from a general trim (or dynamic equilibrium) state are constructed. The linear model is used to reveal the stability properties for the uncontrolled machine and rider near to straight running, and for the derivation of optimal controls. These controls minimize a cost function made up of tracking errors and control efforts. Optimal controls for near-straight-running conditions, with left/right symmetry, and more complex ones for cornering trims are included. Frequency responses of some closed-loop systems, from the former class, demonstrate excellent path-tracking qualities within bandwidth and amplitude limits. Controls are installed for path-following trials. Lane-change and clothoid manoeuvres are simulated, demonstrating good-quality tracking of longitudinal and lateral demands. Pitch torque control is little used by the rider, while yaw and roll torques are complementary, with the former being more useful in transients, while the latter has value also in steady states. Wheel torque is influential on lateral control in turning. Adaptive control by gain switching is used to enable clothoid tracking up to lateral accelerations greater than 1 m s
−2
. General control of the motions of a virtual or robotic unicycle will be possible through the addition of more comprehensive adaptation to the control scheme described.
The Stromal Chloroplast Deg7 Protease Participates in the Repair of Photosystem II after Photoinhibition in Arabidopsis
Authors: Sun Xuwu , Fu Tingjiao , Chen Ning , Guo Jinkui , Ma Jinfang , Zou Meijuan , Lu Congming , Zhang Lixin 
Published: January 2010

Abstract
Light is the ultimate source of energy for photosynthesis; however, excessive light leads to photooxidative damage and hence reduced photosynthetic efficiency, especially when combined with other abiotic stresses. Although the photosystem II (PSII) reaction center D1 protein is the primary target of photooxidative damage, other PSII core proteins are also damaged and degraded. However, it is still largely unknown whether degradation of D1 and other PSII proteins involves previously uncharacterized proteases. Here, we show that Deg7 is peripherally associated with the stromal side of the thylakoid membranes and that Deg7 interacts directly with PSII. Our results show that Deg7 is involved in the primary cleavage of photodamaged D1, D2, CP47, and CP43 and that this activity is essential for its function in PSII repair. The double mutants deg5 deg7 and deg8 deg7 showed no obvious phenotypic differences under normal growth conditions, but additive effects were observed under high light. These results suggest that Deg proteases on both the stromal and luminal sides of the thylakoid membranes are important for the efficient PSII repair in Arabidopsis (Arabidopsis thaliana).
Managing construction waste on‐site through system dynamics modelling: the case of Hong Kong
Authors: Li Hao Jian , Hill Martyn James , Yin Shen Li 
Published: January 2010

PurposeThe purpose of this paper is to provide a decision support tool for construction waste on‐site to achieve better construction and demolition waste management.Design/methodology/approachSystem dynamics methodology is adopted for developing the model.FindingsThe model of managing construction waste on‐site is established. The interconnections of the main activities are included into the model with focus on planning and management where information about the future trend is for better decision making.Practical implicationsConstruction waste generation is dynamic and interactive. Therefore, the model developed can be used as a flexible tool to help practitioners to understand the causes and effects.Originality/valueSince the model allows the users to fine‐tune the input parameters, it is flexible to adjust the model to better reflect the reality according to different conditions. This is an advantage over other static models.