bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmaceutical Innovation and U.S. Cancer Survival, 1992-2003: Evidence from Linked SEER-MEDSTAT Data
Authors: Lichtenberg Frank R.
Published: April 2008

This study examines the impact of pharmaceutical innovation and other factors on the survival of U.S. cancer patients during the period 1992-2003. In particular, it investigates whether cancer survival rates increased more for those cancer sites that had the largest increases in the proportion of chemotherapy treatments that were "new" treatments. We control for other types of medical innovation, i.e. other pharmaceutical innovation, and innovation in surgical procedures, diagnostic radiology procedures, and radiation oncology procedures.Data on observed survival rates, the number of people diagnosed, mean age at diagnosis, and stage distribution are obtained from the National Cancer Institutes SEER public-use data. Estimates of rates of innovation in chemotherapy and other treatment and diagnostic procedures are constructed from the MEDSTAT MarketScan database and other data sources. Treatment innovation indicators based on MEDSTAT data are likely to be useful, albeit noisy, indicators of the treatment innovation experienced by patients in SEER registries. This sampling error is likely to bias the coefficients on the treatment innovation measures towards zero.We compute weighted least-squares estimates of 6 versions of a survival model, based on different survival intervals and functional forms. The chemotherapy vintage coefficient is positive and significant in every model. This indicates that the cancer sites whose chemotherapy vintage (measured by the share of post-1990 treatments) increased the most during the period 1992-2003 tended to have larger increases in observed survival rates, ceteris paribus.We estimate how much lower the survival rate from all cancer sites combined would have been during 1993-2001 in the absence of post-1992 chemotherapy innovation. The estimates indicate that chemotherapy innovation accounted for 74% of the increase in the 1-year observed survival rate for all cancer sites combined during the period 1992-2001. Chemotherapy innovation accounted for smaller fractions of the increases in the 2-year and 3-year observed survival rates for all cancer sites combined during the same period: 51% and 29%, respectively.The coefficients on measures of non-pharmaceutical medical innovation (in radiation oncology, diagnostic radiology, and surgery innovation) are generally not significant. However these measures may be less reliable than the drug innovation measure. They were based upon the year in which the AMA established a new procedure code, which may be a far less meaningful indicator of innovation than the year in which the FDA first approved a drug. This topic warrants further research.
Estimating the Impact of Medical Innovation: A Case Study of HIV Antiretroviral Treatments
Authors: Duggan Mark G , Evans William N
Published: April 2008

As health care consumes a growing share of GDP, the demand for better evidence regarding the effects of health care treatments and how these vary across individuals is increasing. Estimating this with observational data is difficult given the endogeneity of treatment decisions. But because the random assignment clinical trials (RACTs) used in the FDA approval process only estimate average health effects and do not consider spending, there is no good alternative. In this study we use administrative data from California's Medicaid program to estimate the impact of HIV antiretroviral treatments (ARVs). We use data on health care utilization to proxy for health status and exploit the rapid takeup of ARVs following their FDA approval. Our estimate of a 68 percent average mortality rate reduction is in line with the results from RACTs. We also find that the ARVs lowered short-term health care spending by reducing expenditures on other categories of medical care. Combining these two effects we estimate the cost per life year saved at $19,000. Our results suggest an alternative method for estimating the real-world effects of new treatments that is especially well-suited to those treatments that diffuse rapidly following their approval.
Finite Element Simulation of Rough Rice Kernel (Oryza sativa L.) cv. Fajer Drying
Authors: Rafiee Shahin , Omid Mahmoud , Yadollahinia Alireza
Published: April 2008

This study was conducted to present a mathematical model with numerical solutions to predict the mass distributions inside a cross sectional area of an individual Fajer variety of rough rice (Oryza Sativa L.) kernel as a function of drying time considering the effects of coupled heat and mass transfer processes. The modified Luikov's equation was used for the simulation of drying kinetics of a single rough rice grain. The applied drying models with simultaneous heat and mass diffusion in biological materials were developed by finite element method. A finite element formulation and solution of a set of nonlinear coupled conductive heat and diffusive moisture transfer equation to improve grain drying simulation of axisymmetric bodies is presented. Axisymmetric linear triangular elements with two degrees of freedom per node were used to discretize the rice grain. Moisture distribution inside the individual rough rice kernel was produced by the model. Good agreement was observed when the output of nonlinear model was compared to experimental data.
New Mathematical Model of Solar Flux Radiation for Double-Pitched Roof Surface
Authors: Harimi Mohamed , Yeo Kiam Beng , Othman Nordin
Published: April 2008

The aim of this research is to simplify an existing model (model-1) of solar flux radiation containing many parameters as compared to a new mathematical model (model-2) using just two independent variables, time and roof's angle of inclination. The impact of the solar radiation on the surface of the roof in Sabah (state of Malaysia) has been examined under different orientations and slopes by means of model-1 at different time of the day. Furthermore, the data of solar flux radiation computed using model-1 has been explored to develop the model-2 from which the correlation coefficient of 0.87 was achieved using regression analysis. It has been proven statistically using the t-test that the difference between the existing model-1 and the proposed model-2 is not significant. The new mathematical model-2 developed can be applied for a double-pitched roof at any given orientation in the area of Sabah only, where the slope of the roof and the local time have to be taken from 0 to 75 degrees and from 7 hrs to 17 hrs, respectively. Additionally, the method used in the derivation of this new model can also be employed for other states of Malaysia as well as other countries. From a technical point of view, the architects or designers can use the proposed model for a quick estimation of solar flux radiation, to identify the type of insulations to be applied under the roof or above the ceiling, as well as the size area of the natural ventilation and the decision-making on the thermal system to be employed, either as an active or a passive cooling system.
Optimization of a Continuous Process for the Recovery of Lactic Acid Using Differential Evolution Algorithm
Authors: Rahman Imran , Ahmad Arsalan , Kumar Prakash , Kulkarni Bhaskar D.
Published: April 2008

Purified lactic acid is used for production of biodegradable polymer. Esterification with methanol and subsequent hydrolysis in distillation column using cation exchange resin as catalyst to produce purified lactic acid has obvious advantages. In this paper, we present a theoretical study on optimization of industrial production (1000 t/year) of pure lactic acid using differential evolution (DE), a robust global optimization technique. The objective function is to minimize the overall cost with a view to obtain the optimized values of the decision variables: esterification reaction temperature, number of stages, feed location, reflux ratio, catalyst weight, number of reactive stages and position of reactive stages for hydrolysis.
A Modeling and Optimization Tool for the Expandable Polystyrene Batch Process
Authors: Heikkinen Mikko , Nurminen Ville , Hiltunen Teri , Hiltunen Yrjö
Published: April 2008

Expandable Polystyrene (EPS), a material of the insulation productions and packages, is commonly produced in a batch process. The control of the batch process is based on predefined process recipes and process parameters such as mixing properties. The EPS production has to be able to satisfy the aims and quality requirements of the markets, which causes additional demands on the process control. In this paper we demonstrate the optimization and modeling application for the EPS-batch process. The application consists of a production optimization tool and a simulation tool for the process parameters based on the Multi-Layer Perceptron network (MLP) with retrain properties. The software can be used at the operational level as well as at the process management level. The features are programmed into standalone software built up in the Matlab environment and it is tailored for the needs of the EPS production company StyroChem Ltd. The results show that the application can offer an efficient tool to economize production and storage costs.
Influence of Vortex-Finder Diameter on Axial Gas Flow in Simple Cyclone
Authors: Horvath Andras , Jordan Christian , Harasek Michael
Published: April 2008

Several types of flow patterns in cyclones were found in recent publications. As a means for structuring the findings the publications were split up into two classes. Each class represented a certain feature of the axial velocity profile of the gas flow inside the cyclone. Class V represents cyclones with a maximum of the axial velocity at the vortex core of the cyclone, whereas Class W represents cyclones with an axial velocity profile that resembles an upside down W. This class has a local minimum of axial velocity at the vortex core or even displays backflow.The geometries of the cyclones belonging either to Class V or to Class W showed only small relative differences. It was assumed that the diameter of the vortex finder had a great influence on the class membership. This influence was simulated and measured for different basic geometries. The goal of this work was to develop the basics for reliable simulation results using the preprocessor GAMBIT and the finite volume CFD code FLUENT (which also serves as a postprocessor). Laser Doppler Anemometry (LDA) experiments were carried out on a laboratory scale cyclone to verify simulation results.In addition the results of cyclones which were investigated in previously published papers were used as a basis for developing a method of simulation, to validate numerical results and class membership. The prediction of pressure drop over the cyclone is overestimated by FLUENT (regarding the test cases). It was proven experimentally that downstream geometry (pipes etc.) has a great influence on flow profiles inside the cyclone. The axial flow profile can change dramatically if the pipes downstream the vortex finder are removed. A Class V cyclone displaying a maximum of axial velocity at the vortex core can change to a Class W cyclone with a minimum of axial velocity at the vortex core.
Dynamic Behaviour of Thermally Coupled Distillation Arrangements: Effect of the Interconnection Flowrate
Authors: Miranda-Galindo Erick Yair , Segovia - Hernández Juan Gabriel
Published: April 2008

Thermally coupled distillation sequences can provide significant energy savings with respect to the operation of conventional distillation columns. Coupled sequences exhibit a complex structure, with recycle streams, that appear to affect their controllability properties. One potential solution to this problem has been suggested through the operation of complex schemes under conditions that do not provide minimum energy consumption. The basic idea is that if one changes the value of the interconnection flowrate, the control properties might change as well. In this work, we analyze the dynamic behavior of two coupled structures under different operating points, including the one with minimum energy consumption. The control analysis properties are analyzed with the application of the singular value decomposition technique in all frequency domains. The results show that the controllability properties of distillation sequences may change significantly depending on the selected value of interconnection flowrate.
Conflict and Production: An Application to Natural Resources
Authors: Wick Katharina
Published: April 2008

I present a Stackelberg model of conflict, in which contestants have limited endowments to be put in two separate sectors, thus incorporating salient features of many conflicts. The model is applied to the case of conflict over natural resources. Consistent with amounting empirical evidence regarding a so-called "resource curse," I find that the relation between conflict intensity and resource rents is non-monotonous, and that the economy's income growth rate may be negatively affected by resource abundance.
Millers, Commission Agents and Collusion in Grain Markets: Evidence from Basmati Auctions in North India
Authors: Banerji A. , Meenakshi J.V.
Published: April 2008

This paper undertakes structural estimation of asymmetric auction models in a market for basmati, and detects the presence of a cartel consisting of a large (in market share) local miller and commission agents purchasing for large distant millers. The contracts between the distant millers and their commission agents help to explain the specific form that collusion takes. Simulations indicate that (i) the cartel gains considerably by colluding, over the competitive outcome; (ii) however, sellers (farmers) do not lose significantly under collusion when the commission agents bid. The paper also shows that efficient collusion, the form of collusion commonly assumed in the literature, does not explain the data well.
The Economics of Workaholism: We Should Not Have Worked on This Paper
Authors: Hamermesh Daniel S. , Slemrod Joel B
Published: April 2008

A large literature examines the addictive properties of such behaviors as smoking, drinking alcohol, gambling and eating. We argue that for some people addictive behavior may apply to a much more central aspect of economic life: working. Although workaholism raises some of the same health-related concerns as other addictions, compared to most of the more familiar addictions it is more likely to be a problem of higher-income individuals and is more likely to generate negative spillovers onto individuals around the workaholic. Using the Retirement History Survey and the Panel Study of Income Dynamics, we show that high-income, highly educated people exhibit behavior that is consistent with workaholism with regard to retiringthey are more likely to postpone earlier plans for retirement. The theory and evidence suggest that the presence of workaholism calls for a more progressive income tax system than otherwise, although other more targeted policies may be part of optimal policy.
Risk Attitude in Real Decision Problems
Authors: Botti Fabrizio , Conte Anna , Di Cagno Daniela Teresa , D'Ippoliti Carlo
Published: April 2008

We use data from 298 showings of the television program "Affari Tuoi," which involves contestants making decisions between risky prospects with possible prizes of up to half a million euros, to estimate three models of decision-making under risk: Expected Utility, Rank-Dependent Expected Utility and Regret-Rejoice. We find that Regret-Rejoice does not significantly improve upon Expected Utility, while Rank-Dependent outperforms it. Interestingly, we find that the CARA specification fits significantly better than the conventionally-adopted CRRA specification. Crucially, we find a significant role for unobserved heterogeneity, implying that our estimates provide more superior estimates of risk attitude and of probability weighting than other studies.
The Shape of Demand: What Does It Tell Us about Direct-to-Consumer Marketing of Antidepressants?
Authors: Meyerhoefer Chad D. , Zuvekas Samuel H
Published: April 2008

Much of the debate surrounding Direct-to-Consumer Advertising (DTCA) of pharmaceuticals centers on whether DTCA conveys useful information to consumers or indiscriminately increases requests for the advertised medication. By identifying how DTCA changes the shape of the demand curve for antidepressants, we seek to infer the promotional objectives of manufacturers. Using data from the 1996-2003 Medical Expenditure Panel Survey (MEPS), we find that advertising shifts the demand curve for antidepressants outward and rotates it counter-clockwise. DTCA increases the probability that an individual will initiate use of antidepressants, particularly when out-of-pocket medication costs are low, but does not necessarily increase utilization levels among those already taking antidepressants. This is consistent with a promotional campaign that seeks to alert consumers to the product's existence, but conveys no real information that would allow them to learn their true match with the product.
Did 'Targets and Terror' Reduce Waiting Times in England for Hospital Care?
Authors: Propper Carol , Sutton Matt , Whitnall Carolyn , Windmeijer Frank
Published: April 2008

Waiting times have been a central concern in the English NHS, where care is provided free at the point of delivery and is rationed by waiting time. Pro-market reforms introduced in the NHS in the 1990s were not accompanied by large drops in waiting times. As a result, the English government in 2000 adopted the use of an aggressive policy of targets coupled with the publication of waiting times data at the hospital level and strong sanctions for poor performing hospital managers. This regime has been dubbed targets and terror. We estimate the effect of the English target regime for waiting times for hospital care after 2001 by a comparative analysis with Scotland, a neighbouring country with the same healthcare system that did not adopt the target regime. We estimate difference-in-differences models of the proportion of people on the waiting list who waited over 6, 9 and 12 months. Comparisons between England and Scotland are sensitive to whether published or unpublished data are used but, regardless of the data source, the targets and terror regime in England lowered the proportion of people waiting for elective treatment relative to Scotland.
Local Network Effects and Complex Network Structure
Authors: Sundararajan Arun
Published: April 2008

This paper presents a model of local network effects in which agents connected in a social network each value the adoption of a product by a heterogeneous subset of other agents in their neighborhood, and have incomplete information about the structure and strength of adoption complementarities between all other agents. I show that the symmetric Bayes-Nash equilibria of this network game are in monotone strategies, can be strictly Pareto-ranked based on a scalar neighbor-adoption probability value, and that the greatest such equilibrium is uniquely coalition-proof. Each Bayes-Nash equilibrium has a corresponding fulfilled-expectations equilibrium under which agents form local adoption expectations. Examples illustrate cases in which the social network is an instance of a Poisson random graph, when it is a complete graph, a standard model of network effects, and when it is a generalized random graph. A generating function describing the structure of networks of adopting agents is characterized as a function of the Bayes-Nash equilibrium they play, and empirical implications of this characterization are discussed.
Counter Marginalization of Information Rents: Implementing Negatively Correlated Compensation Schemes for Colluding Parties
Authors: Celik Gorkem
Published: April 2008

A principal contracts with a productive agent whose production cost is private information and with an insurer who can insure the principal against variations in the payment to the agent. The insurer and the agent can collude in their responses to the principal's contract. Non-cooperative play of the principal's contract constitutes the outside option for the colluding parties. In this setup, we characterize the implementable outcomes for the principal. We then identify the optimal implementable outcome under the assumption that the principal faces a budget constraint. The optimal outcome provides the principal with "partial" insurance. For higher realizations of the production cost, the budget may not be exhausted even though the principal is not directly concerned with the unspent portion of the monetary funds.
On the Effect of Risk Aversion in Two-Person, Two-State Finance Economies
Authors: Berden Caroline , Peters Hans
Published: April 2008

The effect of replacing an agent in a two-person two-state finance economy by a more risk averse agent is studied. It is established under which conditions the other agent benefits or looses in equilibrium from dealing with a more risk averse agent. If one agent becomes more risk averse, then the equilibrium allocation moves towards that agent's certainty line. Whether or not that is beneficial for the other agent depends on the location of the endowment point.
Identification of Individual Demands from Market Data under Uncertainty
Authors: Carvajal Andres , Riascos Alvaro Jose
Published: April 2008

We show that, even under incomplete markets, the equilibrium manifold identifies individual demands everywhere in their domains. Under partial observation of the manifold, we determine maximal subsets of the domains on which identification holds. For this, we assume conditions of smoothness, interiority and regularity. It is crucial that there be date-zero consumption. As a by-product, we develop a duality theory under incomplete markets.
Conflict and Consensus: A Theory of Control in Organisations
Authors: Banerjee Priyodorshi
Published: April 2008

A principal, requiring a team to implement a project by proposing and jointly executing a technique, may benefit from choosing one with internal disharmony. When superior policy proposition by a member is rewarded with unitary executive control, the benefit of control is increasing in the degree of conflict. Hence, the presence of discord can raise incentives to take effort towards technique proposition by inducing competition for control, and thereby enhance average proposal quality. The principal may thus choose a fractious team when the losses from lower consensus in project execution are limited. These effects can be exacerbated in large teams, and lead to teamwork dominating individual production.
Backward Integrated Information Gatekeepers and Independent Divisions in the Product Market
Authors: Chen Jihui
Published: April 2008

This paper examines the welfare effects of vertical integration by an "information gatekeeper" into the product market it serves. Both the integrated gatekeeper and competing firms in the product market earn higher profits, but social welfare declines.
When Stackelberg and Cournot Equilibria Coincide
Authors: Colombo Luca , Labrecciosa Paola
Published: April 2008

We take a new look at the comparison between the Stackelberg equilibrium and the Cournot equilibrium. We show that, when the elasticity of the inverse market demand equals the curvature of the inverse market demand weighted by the Lerner Index, a generic Stackelberg leader sets the same quantity and earns the same profit as a generic Stackelberg follower. When the curvature of the inverse market demand equals the total number of firms in the industry, a coincidence among the quantities produced by a first mover, a second mover, and a generic firm facing Cournot competition occurs.
Public/Private Joint Service Delivery in American Counties: Institutional Theory of Local Governance and Government Capacity
Authors: Jeong Moon-Gi
Published: April 2008

The question of who should provide public services has continued to gain attention among scholars and practitioners. Existing studies on public service delivery have primarily focused on the `make' or `buy' decision, resulting in their lack of knowledge in public/private joint service delivery, especially at the county level. This study fills the research lacuna by incorporating the institutional theory of local governance and government capacity. Using the 2002 ICMA Survey on Local Governments' Alternative Service Delivery, this study examines what factors account for the adoption of public/private joint service delivery in American counties. Probit analysis is employed to estimate county choice of joint service delivery in 2002. Overall, the findings suggest that the reformed political structure has a modest influence on joint service delivery. The findings also suggest that government capacity has negative influence on joint service delivery.
Mineralogy and Geochemistry of the Nižná Boca Sb-Au Hydrothermal Ore Deposit (Western Carpathians, Slovakia)
Authors: Smirnov Alexander , Pršek Jaroslav , Chovan Martin
Published: April 2008

Mineralogy and Geochemistry of the Nižná Boca Sb-Au Hydrothermal Ore Deposit (Western Carpathians, Slovakia)

Samples from hydrothermal Sb-Au mineralization in the area SE of Nižná Boca village in the N&iAzke Tatry Mountains were investigated using a variety of geochemical and mineralogical methods. Ore minerals typically occur in N-S striking quartz-carbonate veins hosted by an I-type biotite granodiorite to tonalite of Variscan Age (the Ďumbier Type). Paragenetic associations in the deposit are comparable to other mineralizations of the same type in the Ďumbierske Nízke Tatry Mountains. A quartz-arsenopyrite, pyrite stage of mineralization is the oldest with a calculated temperature of formation of about 445°C. It is followed by a quartz-carbonate-stibnite, zinkenite stage and, in turn, a quartz-carbonate-sphalerite-galena, boulangerite-gold stage. The gold typically contains between 9-18 wt.% Ag regardless of mineral association. No evidence for further generations of gold was found although it is possible that some gold was remobilized from the structure of the auriferous arsenopyrite. The Au and Ag content of the bulk ore ranges from 0.53 g.t-1to 20.2 g.t-1and from 0.9 g.t-1to 31.2 g.t-1, respectively. A tetrahedrite-chalcopyrite stage is followed by a barite-hematite stage - the youngest assemblage in the deposit. Fluid inclusions from the first mineralization stage are usually less than 3 μm in size and contain less than 3.6 wt.% CO2; salinity, density and homogenization temperature range from 2.7-16.3 wt.% NaCl(eq), 0.85-1.03 g.cm-1and 128-280°C, respectively.
The Selected Shape-Memory Characteristics of the Ni-Ti Alloy in Thermo-Mechanical Loading Conditions
Authors: KUŚ Krzysztof
Published: April 2008

The Selected Shape-Memory Characteristics of the Ni-Ti Alloy in Thermo-Mechanical Loading Conditions

This paper deals with the testing work to examine some selected shape-memory characteristics (mainly recovery and permanent strains) in the Ni-Ti alloy during the thermomechanical cycling. The variations of shape memory effect (SME) were assessed using a special bending set-up, and discussed with respect to different thermo-mechanical loading profiles. The required phase-transformation temperatures of the alloy under examination were achieved by applying the annealing process at different temperatures for different times. The phase transformation behavior was observed using a differential scanning calorimeter (DSC). The X-ray diffractometry (XRD) was employed to identify phases present after the annealing heat treatment. It was found that the nature of a transformation cycle during two applied thermo-mechanical loading profiles (especially, the stress during reverse phase transformation), and also changes developed in the microstructure of a cycled material can affect behavior of strains.
Effect of Simulated Microgravity on Sexual Development of Female Japanese Quail
Authors: Škrobánek P. , Baranovská M. , Šárniková B. , Juráni M.
Published: April 2008

Hypodynamia is a method to simulate weightlessness (microgravity) in the laboratory conditions. The objective of this study was to investigate the influence of chronic hypodynamia on the growth and development of the ovary and oviduct, plasma estradiol and progesterone concentration, and the onset of egg-laying in Japanese quail. The ovary weight gradually increased with age in both groups. However, the experimental birds subjected to hypodynamia showed a significant reduction in ovary weight relative to age-matched control between 21 and 42 days of age (P < 0.05). The number of yellow follicles with a diameter of less than 10 mm, between 10 and 15 mm and more than 15 mm was similar in both groups from 49 days to the end of experiment. The control birds had significantly longer oviduct than those of the test group from 28 to 63 days (P < 0.05) with the exception of day 49. The quail reared under hypodynamia laid their first egg about three days later than control. Plasma progesterone concentration in experimental quail was significantly reduced between 28 and 49 days (P < 0.05). Plasma estradiol concentration increased progressively with age in both groups. The differences between the groups were not significant at any age. These findings suggest that although hypodynamia negatively affects some of the examined variables, the female Japanese quail is able to grow and develop normally under conditions of simulated weightlessness.
Selenium Dynamics in the Blood of Beef Cows and Calves Fed Diets Supplemented with Organic and Inorganic Selenium Sources and the Effect on their Reproduction
Authors: Slavík P. , Illek J. , Rajmon R. , Zelený T. , Jílek F.
Published: April 2008

The objective of this study was to compare the effects of feed supplementation with sodium selenite or selenized yeast on serum Se levels and reproduction indicators in cattle. In three beef herds young heifers, cows in late pregnancy, and their calves were randomly grouped by 6. In Herd 1, the mean Se serum levels were 51.01 μg l-1 in heifers, 32.12 μg l-1 in cows in late pregnancy, and 29.07 μg l-1 in their calves. In Herd 2, 27.42 μg l-1 (heifers), Z22.9 μg l-1 (late pregnancy), and 23.46 μg l-1 (calves). In Herd 3, 27.07 μg l-1 (heifers), 22 μg l-1 (late pregnant cows), and 31.05 μg l-1 (calves). Over a 6-month period, the animals in Herd 1 were given selenium yeast supplement; in Herd 2 sodium selenite, whereas Herd 3 served as a negative control. Afterwards, a second blood sample was taken. The mean Se serum levels were as follows: Herd 1 (selenium yeast): 90.73 μg l-1 in late pregnant cows ( p < 0.01), 57.99 μg l-1 in calves (p < 0.01); Herd 2 (sodium selenite): 42.08 μg l-1 (late pregnant cows p < 0.01), 37 μg l-1 (calves p < 0.05); Herd 3 (control) 25.77 μg l-1 (late pregnant cows), 32.85 μg l-1 (calves). A significant difference was also observed in the second blood sample taken in both the late pregnant cows and the calves between the Herds 1 and 2 (late pregnant cows p < 0.01, calves p < 0.01). No significant differences were demonstrated between the groups. Herds 1 and 2 showed an improvement in their health status, as compared with the previous period, neither in reproduction indicators nor in the weight gain of the calves.
Transplantation of Mitral Allograft into the Tricuspid Position - a Sheep Experimental Model
Authors: Mokráček A. , Hlubocký J. , Burkert J. , Vojáček J. , Šulda M. , Vambera M. , Kursa J. , Kroupová V. , Kobylka P. , Špatenka J.
Published: April 2008

Our research was focused on finding the optimal technique of cryopreserved mitral allograft implantation into the tricuspid valve position in a sheep experiment. We prepared 20 cryopreserved mitral valve allografts preoperatively. These were implanted into the tricuspid position in 20 sheep via right thoracotomy, using extracorporeal circulation with cardioplegic heart arrest. We consider the transventricular papillary muscle fixation to be the best technique for obtaining optimal allograft geometry and long-term durability. We evaluated the valve function by epicardial echo before and after implantation, respectively. The findings were confirmed by haemodynamic measurements as well. It was proved that mitral allografts, harvested, processed, and stored according to the Cardiovascular Tissue Bank Protocol remained mechanically strong enough for implantation into the tricuspid position. It was demonstrated that the mitral allograft transplantation into the tricuspid position is feasible. The immediate postoperative haemodynamic performance was excellent in all animals. The mid-term results are currently being evaluated - prior to the possible application of the technique in humans at our institutions.
Resistance to Antibiotics in Strains of Staphylococcus spp., Enterococcus spp. and Escherichia coli Isolated from Rectal Swabs of Pigs
Authors: Kolář M. , Bardoň J. , Vágnerová I. , Sauer P. , Koukalová D. , Petrželová J. , Čekanová L. , Pospíšil R.
Published: April 2008

The study aimed at determining the level of resistance of selected bacterial species (Staphylococcus spp., Enterococcus spp., Escherichia coli) isolated from rectal swabs of pigs to antimicrobial agents. The tested strains were isolated from piglets aged 7 to 30 days. Bacterial species were identified by standard microbiological techniques and susceptibility to antibiotics was determined quantitatively by the standard microdilution method. Resistance of the Staphylococcus aureus strain to oxacillin was confirmed by detection of the mecA gene and PBP2a. A total of 115 Staphylococcus spp. isolates were collected. In the case of Staphylococcus aureus, the methicillin-resistant strain (MRSA) was identified. Moreover, higher frequency of coagulase-negative staphylococci with minimum inhibitory concentration of oxacillin ≥ 0.5 mg/l was noticed. Inducible resistance to clindamycin in the Staphylococcus hominis strain was also detected. The strains of Enterococcus spp. (61 isolates) exhibited high resistance to tetracycline (98.5%), erythromycin (86.8%) and chloramphenicol (54.4%). Vancomycin-resistant enterococci were not isolated. In the case of Escherichia coli strains (111 isolates), higher frequency of resistant strains to tetracycline (81.1%) and ampicillin (62.2%) was documented. Resistance to fluoroquinolones and production of broad-spectrum β-lactamases was not noticed. The presented study may be considered as a pilot project assessing the prevalence of resistant bacteria in piglets kept on a single farm. It demonstrated the presence of resistant strains of Staphylococcus spp., including one MRSA strain, Enterococcus spp. and Escherichia coli. These strains may be present as a result of postnatal colonization with both bacterial microflora of dams and environmental microflora.
Prevalence of Coccidian Species in the Water Buffalo (Bubalus Bubalis) in the Province of Afyon, Turkey
Authors: Nalbantoglu S. , Sari B. , Cicek H. , Karaer Z.
Published: April 2008

The objective of this study was to identify the coccidian species present in water buffaloes in the vicinity of Afyon. Faecal samples were collected directly from the rectum of a total of 104 water buffaloes, and examined in the laboratory using Sheather's saturated sugar solution. Faecal samples found to contain Eimeria species were mixed with a solution of 2.5% potassium dichromate, left at room temperature in petri dishes until the oocysts sporulated, and then examined in order to identify the species. Eleven different Eimeria species and one Isospora species were identified in 78 (75%) out of the 104 water buffaloes as follows: E. zuernii (55.1%), E. auburnensis (44.9%), E. bovis (44.9%), E. ellipsoidalis (28.2%), E. ankarensis (16.7%), E. subspherica (16.7%), E. alabamensis (11.5%), E. cylindrica (10.3%), E. bareillyi (5.1%), E. canadensis (5.1%), E. brasiliensis (3.8%), and Isospora spp. (46.2%). With this study, species causing coccidiosis in water buffaloes in the province of Afyon were identified for the first time, and Isospora spp. in the water buffalo is reported for the first time.
Serological Investigations of Brucellosis in Cattle, Farmers and Veterinarians in the Kars District of Turkey
Authors: Otlu S. , Sahin M. , Atabay H. I. , Unver A.
Published: April 2008

The prevalence of brucellosis was investigated in cattle, farmers and veterinarians in the Kars district of Turkey between 2004 - 2006. In order to achieve this, a total of 407 serum samples of cattle from 27 herds having history of abortions were examined for Brucella antibodies by RBPT and SAT. In addition, the sera collected from 246 farmers (130 males and 116 females) and 28 veterinarians in the same district were analysed serologically by RBPT, SAT and ELISA. Of the cattle sera analysed, 134 (32.92%) and 141 (34.64%) were determined as positive by RBPT and SAT, respectively. Thirty-two (13%), 35 (14.22%) and 44 (17.88%) of the farmers' sera were found positive for brucellosis by RBPT, SAT and ELISA, respectively. There was no significant difference between sexes for Brucella seropositivity. Of the 28 sera from veterinarians, 13 (46.42%) were positive by the three serological tests. The high prevalence of brucellosis both in cattle and humans suggests that brucellosis is common in this area. Preventive and control measures should be implemented and pursued more strictly to reduce and/or eradicate brucellosis from the area.
Purulent Trunk Dermatitis in a Male Ceylon Elephant (Elephas maximus maximus)
Authors: Vodička R.
Published: April 2008

The study describes the therapy of purulent trunk dermatitis in an aggressive male Ceylon elephant (Elephas maximus maximus). The elephant was immobilized 4 times with 1.7 ml Large Animal (LA) Immobilon i.m. within 50 days. The anaesthetic action was antagonised with 1.7 ml LA Revivon + 8.0 ml Naloxone i.v. and 0.5 ml LA Revivon + 6.0 ml Naloxone i.m. From skin lesions the following pathogens were isolated: Staphylococcus spp., Streptococcus spp. and Candida tropicalis. Local therapy consisted of the debridement of the affected skin, application of antibiotics and skin antiseptics. Depot penicillin, vitamins, probiotics and autogenous yeast vaccine were administered generally. In haematological indicators the biggest changes were found in the numbers of white blood cells and segmented neutrophils. Markedly low zinc concentrations were found repeatedly. Despite the non-standard steps we took (repeated anaesthesia during a short time, non-compliance with the recommendations for the administration of some drugs, etc.) and difficult handling (aggressive, uncontrollable elephant, no restraint chute), it proved possible to treat such a case in this manner.
Synthetic Culture Media Evaluated for the Detection of Coliform Bacteria in Milk, Cheese and Egg Melange
Authors: Szita G. , Gyetvai B. , Szita J. , Gyenes M. , Solymos N. , Soos L. , Hajos A. , Toth P. , Bernáth S.
Published: April 2008

Simple synthetic culture media of liquid and solid form (X broth and X agar) were tested for selective isolation of coliform bacteria. Selectivity is based on the ability of coliform bacteria to grow when the minimal medium contains simple inorganic substances as nitrogen and carbon supply. Selectivity of the media was tested by inoculation of pure cultures of different microbes belonging to the genera of Staphylococcus, Bacillus and Pseudomonas and the family Enterobacteriaceae and was found to be complete in this range. The comparative investigation of milk, camembert cheese and egg melange samples in the traditional and new media proved good applicability of X broth and X agar for an effective and selective detection of coliform bacteria. When testing pasteurized milk samples, X agar detected coliforms in significantly higher counts than violet red-bile-lactose agar.
AFL Research in the L2 Classroom and Evidence of Usefulness: Taking Formative Assessment to the Next Level
Authors: Colby-Kelly Christian , Turner Carolyn E.
Published: April 2008

Abstract:

Recent trends in classroom evaluation seek innovative formative assessment intended to benefit learning, called assessment for learning (AFL), largely unresearched in the second language (L2) classroom (Rea-Dickins, 2004). This paper calls for taking L2 testing research to the next level, investigating the ‘usefulness’ ( Bachman & Palmer, 1996 ; Bachman, 2005 ) of formative assessment and AFL. We present data and preliminary results of a study of assessment practices in pre-university English for Academic Purposes (EAP) classes; participants include 9 teachers and 42 students. We describe five types of feedback from speaking tasks, and the assessment bridge, the area of classroom practice linking assessment, teaching and learning. A mixed-methods approach was used, including curriculum document analysis, questionnaires, interviews and classroom observations.
Assessment for Learning: Integrating Assessment, Teaching, and Learning in the ESL/EFL Writing Classroom
Authors: Lee Icy
Published: April 2008

Abstract:

Assessment for learning (AfL) is a relatively new concept in ESL/EFL writing. In AfL, learning is a goal in its own right, and assessment is the means to achieving the goal. Despite an emphasis on assessment the concept AfL appears to suggest, in implementing AfL teachers need to integrate teaching, learning and assessment rather than focus exclusively on how to assess student writing per se. This article aims to discuss the key concepts of AfL with reference to writing and provide practical suggestions to help ESL/EFL writing teachers implement AfL in their own classroom.
Central Retinal Artery Occlusion With Cilioretinal Artery Sparing After Semaglutide Injection
Authors: Shabto Julie M. , Oh Jin Kyun , Sharma Tarun
Published: February 2025

This case report highlights a temporal relationship between the use of a glucagon-like peptide-1 receptor (GLP-1) agonist and the occurrence of central retinal artery occlusion.
Aligning Alzheimer Disease Biology With Care
Authors: Ketchum Fred B. , Chin Nathaniel A. , Grill Joshua D.
Published: February 2025

This Viewpoint discusses the potential benefits and drawbacks of a biological, rather than clinical, framework for the diagnosis of Alzheimer disease.
Prognostication and Biomarker Potential of C26:0 Lysophosphatidylcholine in Adrenoleukodystrophy
Authors: Billington Charles J. , Rayannavar Arpana , Tryon Rebecca , Kaye Tory , Gupta Ashish , Lund Troy C. , Lteif Aida , Adriatico Katherine L. , Orchard Paul J. , Miller Bradley S. , Pillai Nishitha R.
Published: February 2025

This cohort study conducted among Minnesota children diagnosed with adrenoleukodystrophy through newborn screening examines correlation of C26:0 lysophosphatidylcholine (C26LPC) with clinical phenotype over 5 years and recommends adjusting early childhood surveillance regimens in children with lower C26LPC levels.
Can Vaginal Seeding Improve Health Outcomes of Infants Born by Cesarean Delivery?
Authors: Hourigan Suchitra K. , Mueller Noel T. , Dominguez-Bello Maria Gloria
Published: February 2025

This Viewpoint discusses microbiome restoration by vaginal seeding in infants born by cesarean delivery and the potential of vaginal seeding to mitigate diseases associated with cesarean birth.
Analysis of the elements of metacommunity structure in a Mediterranean basin: implications in the framework of global change
Authors: Tierno-Cinque Alejandra , Tierno de Figueroa José Manuel , Luzón-Ortega Julio Miguel , López-Rodríguez Manuel Jesús
Published: February 2025

Metacommunity studies have been gaining in importance in recent decades due to their relevance when interpreting community dynamics. The elements of metacommunity structure (EMS), i.e. coherence, turnover and boundary clumping, are used to assess the assembly of metacommunities. In the present study we analysed the EMS of the Guadiana Hydrographic Demarcation, a prominant seasonal basin located in the southern Iberian Peninsula characterised by a Mediterranean climate, with dry reaches and disconnected pools frequent in streams during the summer. We studied the EMS of the four different taxocoenoses used to assess the ecological status of streams and rivers according to the European Water Framework Directive (diatoms, macrophytes, macroinvertebrates and fishes), both independently of each other and taken together. These analyses were carried out using three different approaches: (1) using a gradient from reciprocal averaging analysis; (2) following a geographical gradient; and (3) following an environmental gradient. We found that the four groups of organisms analysed had either a Clementsian metacommunity structure or a similar structure. When all groups were considered together, the structure of the metacommunity was Clementsian or quasi-Clementsian. Thus, in the framework of the current global change scenario, communities in this basin may be vulnerable to increasing isolation due to more frequent and larger dry periods; consequently, management measures should be considered.
Impact of Resistance Training on Bone During 40% Caloric Restriction in Growing Female Rats
Authors: Sumida Ken D. , Smithers Daniel L. , Gerston Aaron , Lagerborg Kim A. , Jaque S. Victoria , Caporaso Fred
Published: February 2025

There is a growing trend in the use of severe caloric restrictive diets among normal weight young females that can jeopardize bone health. Using an animal model, the purpose of this study was to determine whether resistance training (RT) could maintain bone health during a 6-week severe caloric restrictive (CR) diet in growing female rats. Twenty-four female rats (~ 8 weeks old) were randomly divided into the following groups: sedentary rats fed a normal diet (N = 8), sedentary rats fed a 40% CR diet (D = 8), and an RT group fed a 40% CR diet (DT = 8). The DT group climbed a vertical ladder four consecutive times (per exercise session) with weights appended to their tail 3 days/week for a total of 6 weeks. Tibial bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry scans and bone mechanical properties were measured. After 6 weeks, the body mass (Mean ± SD) of CR-fed groups (D & DT = 202.8 ± 10.7 g) was significantly lower than N (275.5 ± 25.3 g). Tibial BMD (g/cm2) for D (0.196 ± 0.012) was significantly lower vs. N (0.213 ± 0.013), resulting in a 7.9% decline. The tibial BMD for DT (0.206 ± 0.009) resulted in a 3.3% decline compared to N that was not significantly different. Bone mechanical properties were significantly greater for DT compared to D, but not significantly different compared to N. Resistance training has the potential to maintain bone health during severe caloric restriction in growing female rats.
Sequentially timed all-optical mapping photography with thin-plate-based spectral broadening for advanced laser ablation system compatibility
Authors: Shimada Keitaro , Sun Huijie , Saiki Takao , Ito Yusuke , Nakagawa Keiichi
Published: February 2025

Sequentially timed all-optical mapping photography (STAMP) is a powerful technique for capturing the poorly reproducible ablation dynamics induced by ultrashort laser pulses. However, its application in ablation visualization is limited by system complexities and the need for a broad probe wavelength band. In this paper, we present a compact STAMP solution employing thin-plate-based spectral broadening, which enables seamless integration into conventional narrowband pump-probe imaging systems for laser ablation. The system is organized into three modules: spectral broadening using a CaF2 thin plate, pulse stretching with a grating pair or spectrum shuttle, and 2D spectral imaging using a spectral filtering system. This setup allows for the single-shot acquisition of 24-frame sequential images, with a temporal window of up to 400 ps in the 515-nm wavelength band, which corresponds to the second harmonic of Yb-based lasers. The system demonstrated ultrafast imaging of laser ablation in glass using the 800-nm fundamental band of a Ti:sapphire laser for ablation and the 515-nm band generated via optical parametric amplification for probing. Finally, the system applicability to narrow-bandwidth light sources was validated by integrating the packaged STAMP system into a Yb:KGW laser setup and extending the second harmonic’s bandwidth from 5 to 9 nm. The compatibility of this STAMP system with various laser ablation systems opens new avenues for investigating complex ablation dynamics, offering single-shot imaging in a more accessible and versatile format.