bluuebunny/crossref_metadata_2025 huggingface dataset:
Co-composting of distillery and winery wastes with sewage sludge
Authors: Bustamante M.A. , Paredes C. , Moral R. , Moreno-Caselles J. , Pérez-Murcia M.D. , Pérez-Espinosa A. , Bernal M.P.
Published: July 2007

The winery and distillery wastes (grape stalk and marc (GS and GM, respectively), wine lees (WL) and exhausted grape marc (EGM)) are produced in great amounts in the Mediterranean countries, where their treatment and disposal are becoming an important environmental problem, mainly due to their seasonal character and some characteristics that make their management difficult and which are not optimised yet. Composting is a treatment widely used for organic wastes, which could be a feasible option to treat and recycle the winery and distillery wastes. In this experiment, two different piles (pile 1 and 2) were prepared with mixtures of GS, GM, EG and sewage sludge (SS) and composted in a pilot plant by the Rutgers static pile composting system. Initially, GS, GM and EGM were mixed, the pile 1 being watered with fresh collected vinasse (V). After 17 days, SS was added to both piles as a nitrogen and microorganisms source. During composting, the evolution of temperature, pH, electrical conductivity, total organic C, total N, humic acid-like C and fulvic acid-like C contents, C/N ratio, cation exchange capacity and germination index of the mixtures were studied. The addition of V in pile 1 produced higher values of temperature, a greater degradation of the total organic C, higher electrical conductivity values and similar pH values and total N contents than in pile 2. The addition of this effluent also increased the cation exchange capacity and produced a longer persistence of phytotoxicity. However, both piles showed a stabilised organic matter and a reduction of the phytotoxicity at the end of the composting process.
The Effect of Foreign Direct Investment on Domestic Capital Formation, Trade, and Economic Growth in a Transition Economy: Evidence from China
Authors: Xu Gang , Wang Ruifang
Published: July 2007

Studies of the effects of foreign direct investment (FDI) in the developing countries have reported many conflicting results. In this study, we test the effects of inward FDI on China's domestic capital formation, exports, imports, and GDP growth. To that end, we estimated four econometric equations using a data set covering the 1980-1999 period. A key finding of our research is that it was in the 1990s that inward FDI began to exert a significant effect in the Chinese economy. Our regression results show that the inflow of FDI has stimulated domestic investment in China. The growing presence of FDI appears to have enhanced the investment efficiency in the Chinese economy. Inward FDI is also found to have significantly increased China's exports and imports. The policy implications of our main findings are discussed. Several methodological issues pertaining to FDI research in China are also discussed.
Kinetics and Fluid Dynamics for Oil Residue Hydroconversion in Commercial Software
Authors: Yamada T S , Guirardello R
Published: July 2007

The current work is a computational simulation, with the geometry of the Parr reactor series 4581, of a multiphase system with two fluids (hydrocarbon and hydrogen) and two domains (tank and impeller) for the kinetics of residue catalytic hydrocracking. The fluid dynamics modeling is based on the SPH process and the fundamental equations of mass balance and momentum quantities in an isothermal system. The turbulence phenomena are considered through the k-? model for the hydrocarbon and ``disperse phase zero equation" for the hydrogen. The chemical reactions are modeled by the means of a reactional net based on the pseudo components concept, with their loads and products separated according to the commercial cuts, schematized with six parallel reactions, three thermal and three catalytic, with pseudo-first order reaction rates. The domains are composed of hydrocarbon as a general fluid (a mixture of pseudo components + catalyst = ``slurry phase") and the hydrogen as an ideal gas.
Soot Activation Energy for a Xylene-Fueled CVD Reactor
Authors: Wasel Wahed , Kuwana Kazunori , Saito Kozo
Published: July 2007

The past attempts of Arrhenius plots of carbon nanotube (CNT) yield (or CNT length) to obtain the overall activation energy for CNT formation under changing reaction temperature conditions have created substantial errors. Here we propose an inverse method to accurately account for the effect of temperature on gas-phase reactions and species composition. The overall activation energy of soot formation for a xylene-based CVD reactor was calculated and successfully compared with the measured gas-phase concentration data. Our proposed inverse method is expected to help improve the performance of CVD reactors and optimize its design.
Understanding the Effect of the Transition Period during the Air Gasification of Dried Sewage Sludge in a Fluidized Bed Reactor
Authors: Aznar María , González Ángel E. , Manyà Joan J , Sánchez José L. , Murillo M Benita
Published: July 2007

Air gasification of dried sewage sludge (DSS) in a fluidized bed has been studied as an effective alternative for the management of this material in a usable way. Nevertheless, one of the major issues in this technology is to deal with the tar formed during the process. To minimize the tar production, it is very important to optimize the operating conditions. In a previous work (Manyà et al., Energy Fuels, Vol. 19, 629636, 2005) some unexpected results, in which tar production increases with the equivalence ratio, have been obtained. As it has been mentioned in that work, tar production could present unexpected trends while the bed composition changes from sand to a mixture of char and sand. Ashes contained in char have catalytic active metals which could promote gasification reactions. As the char content in the bed increases, the catalytic activity in the reactor could increase too, until the steady state is achieved. The aim of this work is to characterize the non-stationary period and its influence on the overall results obtained from gasification tests. Experiments have been carried out in a laboratory-scale BFB reactor at atmospheric pressure and at a reactor temperature of 1123 K with an equivalent ratio of 30%. Results show that at the beginning of the experiments the tar production was higher, until the steady state is reached. The gasification study has been enhanced with an analysis of tar composition by means of GC/MS and GC/FID. An effect of the transition period has been observed in tar composition also. The nitrogen aromatics percent increased with time whereas the polycyclic aromatic hydrocarbon decreased.
Reconstructing Gene Regulatory Networks with Bayesian Networks by Combining Expression Data with Multiple Sources of Prior Knowledge
Authors: Werhli Adriano V , Husmeier Dirk
Published: July 2007

There have been various attempts to reconstruct gene regulatory networks from microarray expression data in the past. However, owing to the limited amount of independent experimental conditions and noise inherent in the measurements, the results have been rather modest so far. For this reason it seems advisable to include biological prior knowledge, related, for instance, to transcription factor binding locations in promoter regions or partially known signalling pathways from the literature. In the present paper, we consider a Bayesian approach to systematically integrate expression data with multiple sources of prior knowledge. Each source is encoded via a separate energy function, from which a prior distribution over network structures in the form of a Gibbs distribution is constructed. The hyperparameters associated with the different sources of prior knowledge, which measure the influence of the respective prior relative to the data, are sampled from the posterior distribution with MCMC. We have evaluated the proposed scheme on the yeast cell cycle and the Raf signalling pathway. Our findings quantify to what extent the inclusion of independent prior knowledge improves the network reconstruction accuracy, and the values of the hyperparameters inferred with the proposed scheme were found to be close to optimal with respect to minimizing the reconstruction error.
Using Literature and the Arts to Teach Nursing
Authors: Freeman Linda H , Bays Cathy
Published: July 2007

Faculty consistently build on the basic sciences of the pre-nursing curriculum to teach nursing content. They less frequently build on a literature and arts foundation. Both medical and nursing literature contain numerous, specific examples of how literature and arts can be used in courses. This paper provides a rationale for using literature and the arts to teach nursing, an overview of use and research findings from a review of the literature, and a table illustrating how faculty select teaching strategies incorporating literature and the arts.
The Gender Pay Gap
Authors: Blau Francine D , Kahn Lawrence M
Published: July 2007

After decades of near constancy at 40 cents on the dollar, the gender pay gap has declined markedly. Francine Blau and Lawrence Kahn document these developments and explore the reasons both for the remaining gender pay gap and changes in the gap over time.
A Meaningful Second Commitment Period for the Kyoto Protocol
Authors: Olmstead Sheila M , Stavins Robert N
Published: July 2007

Robert Stavins and Sheila Olmstead propose ways to modify the Kyoto Protocol for its second commitment period (2012-2016) so that it will provide a way forward that is scientifically sound, economically rational, and politically pragmatic.
Letter: Why Not Just Ask the Dolphins?
Authors: Kendall Todd D
Published: July 2007

Adam Smith's methodology -- and the modern economist's -- is one of theory, led by observation. Alternative methodologies, including opinion surveys of businessmen are no more likely to generate useful answers than this time-tested epistemology.
Global Climate Change: A Challenge to Policy
Authors: Arrow Kenneth J
Published: July 2007

Kenneth J. Arrow explains why something must be done to limit global warming even if the Stern Report inadequately discounted future costs.
Distributed Generation Capacity Evaluation Using Combined Genetic Algorithm and OPF
Authors: Harrison Gareth P , Piccolo Antonio , Siano Pierluigi , Wallace A. Robin
Published: July 2007

A range of techniques has been proposed to define the optimal locations and capacities of distributed generation (DG) as a means of ensuring that the maximum amount of DG can be connected to existing and future networks. However, there are limitations inherent in these methods, not least in finding the best combination of sites for connecting a predefined number of DGs. Here, a method combining optimal power flow and genetic algorithms aims to meet this requirement. Its use would be in enabling Distribution Network Operators to search a network for the best sites and capacities available to strategically connect a defined number of DGs among a large number of potential combinations. Some applications of the proposed methodology confirmed its effectiveness in sitting and sizing an assigned number of DG units.
Forecasting Influent-Effluent Wastewater Treatment Plant Using Time Series Analysis and Artificial Neural Network Techniques
Authors: Al-Asheh Sameer , Mjalli Farouq Sabri , Alfadala Hassan E.
Published: July 2007

We consider the problem of predicting the future behavior of wastewater treatment plant quality indicators by creating prediction models using historical plant data. One of the main aims of this work is to be able to predict plant operational situations in advance so that corrective actions can be taken in time. Sets of historical plant data, such as BOD, COD and TSS were collected for a local wastewater treatment plant in Doha, the capital of the State of Qatar. These variables characterize the performance of any wastewater treatment plant and can be considered as quality indicators of the plant performance. Data were collected over a period of 4 years for the influent and effluent streams of the station. The plant influent and effluent predictions were performed using different techniques. These include time-series analysis, where the ARIMA (Autoregressive Integrated Moving Average) model was implemented in this case, and two Artificial Neural Networks (ANN) algorithms, namely Adaptive Linear Neuron networks (ADALINE) and Multi-layer Feedforward (ML-FF) neural networks. The predictions from the three techniques were presented and compared. The ML-FF model predictions proved to be more reliable than that of the equivalent ARIMA predictions followed by the ADALINE predictions, particularly for the finial effluent stream variables.
Prediction of Biomedical Waste Load at Centralized Treatment Facility
Authors: Katoch Surjit Singh , Kumar Vineet
Published: July 2007

The Local Municipal Corporation operates a centralized treatment facility (CTF) to facilitate effective and safe disposal of hazardous biomedical waste generated from various health care facilities (HCFs) in a region. Managing these wastes is a challenging task due to unpredictable variation in amount of waste received at a CTF. In this paper a mathematical model is presented that predicts the load on CTF as a function of bed occupancy of some representative hospitals in the region. Models are available to predict waste generated from a particular hospital in terms of bed occupancy; however, it is difficult to predict total waste received at CTF that also includes wastes from HCFs other than hospitals. To develop the model, data for the waste generated at source and for waste incinerated at CTF were collected for two consecutive years on daily basis. It was observed that two hospitals are representative of the rate of biomedical waste generation in the region from all HCFs. In two consecutive years, there were significantly different trends in overall waste incinerated at CTF. The reason for variation in waste load at CTF was observed to be due to uneven load on the HCFs in two consecutive years.
Simulation of Free Chlorine Decay and Adaptive Chlorine Dosing by Discrete Time-Space Model for Drinking Water Distribution System
Authors: Muslim Abrar , Li Qin , Tadé Moses O.
Published: July 2007

An ideal drinking water distribution system (DWDS) must supply safe drinking water with free chlorine residual (FCR) in the form of HOCl and OCl- at a required concentration level. The FCR as a disinfectant decreases over time due to chemical reactions in the bulk phase and at the pipe wall in the DWDS. In order to supply drinking water with the FCR concentration within the safety range of 0.2-0.6 mg/l at the points of water consumption, it is important to develop a dynamic model of the FCR using a discrete time-space model (DTSM) that accounts for free chlorine transport in the axial direction by convection, diffusion and the decay kinetic. A DTSM has been developed using Finite Difference Method (FDM) to predict the FCR in single pipes in the DWDS. The DTSM has been computed using Matlab 7.0.1 and tested with step inputs and rectangular pulse inputs to estimate the FCR at any point in the pipes over time. Data found in the literature have been used to validate the DTSM. The modelling and simulation study shows that the water velocity significantly affects the FCR concentration distribution along the pipe. Due to the fluctuation of the drinking water demand, a model-based adaptive chlorine dosing scheme is proposed to control the proper injection of chlorine.
Dynamic Simulation of Reactive Batch Distillation Column for Ethyl Acetate Synthesis
Authors: Patel Rahul , Singh Kailash , Pareek Vishnu , Tadé Moses O.
Published: July 2007

A detailed mathematical dynamic model of reactive batch distillation column is formulated for ethyl acetate synthesis and presented in terms of differential and algebraic equations (DAEs). These DAEs are solved using fourth order Runge-Kutta method in MATLAB® to obtain the detailed column dynamics. The simulation results provide the dynamics of reboiler and distillate compositions, reboiler temperature, ethyl acetate purity in the accumulated distillate and conversion of the reactants. These results are analyzed to derive the optimum operating policy, i.e., reflux ratio and batch time.
Numerical Simulation of Electrolyte Two-Phase Flow Induced by Anode Bubbles in an Aluminum Reduction Cell
Authors: Zhou Naijun , Xue Yuqing , Chen John J J , Taylor Mark.P.
Published: July 2007

In the production process of aluminium reduction cells, the anode bubble laden layer has several important influences on the performance of the aluminium reduction cells. Especially for a "drained cathode cell", without the agitating of movement of the melted metal, the bath flow field could be more important. In this paper, the electrolyte two-phase flow fields were studied by using numerically simulation method based on a two-phase turbulence model combining the k - ? model and the Discrete Random Walk model. The results show that: the motion of the bubbles mostly exists within a thin layer under the anode, which results in inducing local electrolyte to flow around the anode in various circulation flows; the flow field in the anode-cathode space can be divided into three regions with different characters; the results also show the Driving action of bubbles is closely related to the current density, inclination of anode and the anode-cathode distance. In general, the increasing in the current density increases the electrolyte velocity and the turbulent kinetic energy. The decrease in ACD significantly enhances the uniformity of the electrolyte flow field in the anode-cathode space. The increase in anode inclination angle increases the velocity of the electrolyte in the anode-cathode space, which would be beneficial to improving the diffusion and dissolution of the alumina and reducing the resistance between the anode and cathode.
Alcohol Control Policies and Youth Alcohol Consumption: Evidence from 28 Years of Monitoring the Future
Authors: Carpenter Christopher S , Kloska Deborah D , O'Malley Patrick , Johnston Lloyd
Published: July 2007

We provide the first historical comparative analysis of the effects of Minimum Legal Drinking Ages (MLDA), beer taxes, and "Zero Tolerance" (ZT) underage drunk driving laws on the drinking behaviors of high school seniors using confidential area-identified data from the 1976-2003 waves of the Monitoring the Future (MTF) Surveys. We estimate reduced form models of drinking participation and heavy episodic drinking that account for state and year fixed effects. Our findings confirm that nationwide increases in the MLDA in the late 1970s and 1980s and adoption of ZT laws in the 1990s both significantly reduced alcohol consumption by high school seniors, with larger effects for the MLDA than for ZT laws. Higher beer taxes are also estimated to reduce youth drinking participation. Overall, the results confirm that a variety of types of government intervention can have important effects on youth alcohol consumption.
Cross and Double Cross: Comparative Statics in First Price and All Pay Auctions
Authors: Hopkins Ed , Kornienko Tatiana
Published: July 2007

This paper analyses comparative statics for first price auctions and all pay auctions with independent private values. In all pay auctions, bidders with low values will respond to a stochastically higher (in the sense of likelihood ratio dominance) distribution of types by playing less aggressively while high value bidders bid more. In the first price auction, a similar change results in all types playing more aggressively. Furthermore, we show that a decrease in dispersion of values, in the sense of a refinement of second order stochastic dominance, although also associated with an increase in competitiveness, may in addition result in less aggressive play by bidders with high values in both auction forms. We also find similar considerations in an oligopoly game with incomplete information: stochastically lower costs can lead to higher prices.
Best Agendas in Multi-Issue Bargaining
Authors: Flamini Francesca
Published: July 2007

We study the agenda selection problem faced by a multi-issue committee when there can be (small) delays between the negotiations of different issues. We show that the presence of these delays affects the interplay of the forces in the bargaining game and solves the indeterminacy of equilibria. In particular, a unique SPE can be established among sequential bargaining procedures. In equilibrium, players discuss the most important issue first.
A Profile of Americans’ Media Use and Political Socialization Effects: Television and the Internet's Relationship to Social Connectedness in the USA
Authors: German Daniel , Lally Caitlin
Published: July 2007

This research project traces the media use habits of children and adults. Over time, television consumption is increasing even though computer and Internet activities are also rapidly increasing. The American people are consuming greater amounts of electronic media while traditional newspaper use is declining. It appears that people are not connecting face to face as much as in the past and live more and more in the individualized world of media. Furthermore, a digital divide based on socio-economic status and race is evident. Blacks use television more than Whites and Hispanics and African Americans and Hispanics use the computer less than Whites. Both of the developments of increased media use and the digital divide do not bode well for (1) building the social capital of connectedness, and (2) widening access to political information which fuels democracy. The political socialization process and hence American political culture are developing new patterns which should be carefully monitored in the future.
Spinitectus mariaisabelae n. sp. (Nematoda: Cystidicolidae) from the intestine of the freshwater fish Profundulus punctatus (Cyprinodontiformes) in Mexico
Authors: Caspeta-Mandujano J. , Cabañas-Carranza G. , Salgado-Maldonado G.
Published: July 2007

Spinitectus mariaisabelae n. sp. is described from the intestine of Profundulus punctatus (Günther) (Pisces, Cyprinodontiformes) from the Suchiapa River, State of Chiapas, Mexico. It is characterized largely by the bifurcate distal tip of the larger (left) spicule, spination of the cuticle separated into 4 longitudinal sectors, more or less regularly spaced rings of spines, and by the position of the excretory pore just posterior to the 7th ring of visible spines. By having the rings of spines divided into 4 sectors, the new species resembles 8 of the 15 American species; however, they can be easily distinguished by the number of spines in the first ring. S. mariaisabelae differs from all its American congeners by possessing a bifurcate distal tip of the left spicule, a unique feature among Spinitectus spp.
Impact of praziquantel baiting on intestinal helminths of foxes in southwestern Germany
Authors: Romig T. , Bilger B. , Dinkel A. , Merli M. , Thoma D. , Will R. , Mackenstedt U. , Lucius R.
Published: July 2007

Fox baits containing 50 mg praziquantel were distributed by aircraft in a 3000 km2 area of southwestern Germany from 1995 to 1999. 20 baits / km2 were initially distributed at intervals of six to twelve weeks. Starting from a prebaiting prevalence of 64 % (95 % C.I. 59–69), a level of 15 % (C.I. 10–21) was reached after 18 months. Further decreasing the frequency and discontinuing the bait distribution caused a surge to 55 % (C.I. 49–61) within 36 months. Other cestode species (Taenia spp., Mesocestoides spp.) showed similar responses, while the prevalence of ascarid nematodes did not decline during baiting. New infections of fox cubs with E. multilocularis, but not with other cestodes, drastically decreased after one year. Prevalences of fox helminths in an external control area remained stable. Our data suggest that repeated praziquantel treatment of free ranging foxes is suitable to reduce the prevalence of E. multilocularis in a large area.
On a cancellation rule for subdirect products of lattice ordered groups and of GMV-algebras
Authors: Jakubík Ján
Published: July 2007

The notion of internal subdirect decomposition can be defined in each variety of algebras. In the present note we prove the validity of a cancellation rule concerning such decompositions for lattice ordered groups and for GMV-algebras. For the case of groups, this cancellation rule fails to be valid.
Oscillation and stability of nonlinear discrete models exhibiting the Allee effect
Authors: Elabbasy E. , Saker S. , El-Metwally H.
Published: July 2007

In this paper, we consider the discrete nonlinear delay population model exhibiting the Allee effect (*)
$$x_{n + 1} = x_n \exp \left( {a + bx_{n - \tau }^p - cx_{n - \tau }^q } \right),$$
where a, b and c are constants and p, q and τ are positive integers. First, we study the local stability of the equilibrium points. Next, we establish some oscillation results of nonlinear delay difference equations with positive and negative coefficients and apply them to investigate the oscillatory character of all positive solutions of equation (*) about the positive steady state x
* and prove that every nonoscillatory solution tends to x
*.
Some remarks on functions with values in probabilistic normed spaces
Authors: Goleţ Ioan
Published: July 2007

In this paper we consider an enlargement of the notion of the probabilistic normed space. For this new class of probabilistic normed spaces we give some topological properties. By using properties of the probabilistic norm we prove some differential and integral properties of functions with values into probabilistic normed spaces. As special cases, results for deterministic and random functions can be obtained.
A note on exponent of convergence of zeros of entire functions
Authors: Lahiri B. , Banerjee Dibyendu
Published: July 2007

If f(z) is an entire function with ρ
1 > 0 as its exponent of convergence of zeros and if 0 ≤ α < ρ
1, then we prove the existence of entire functions each having α as its exponent of convergence of zeros.
New Data on the Post-Impact Material in Radiolarian Horizons in Outer Flysh Carpathians and Search for a Source Crater
Authors: Paul Zbigniew , Halas Stanislaw , Wójtowicz Artur
Published: July 2007

In the Outer Carpathians in Barnasiówka radiolarian shale formation, there is an intercalation underlied by bentonite. There were found very rare elements and minerals in this intercalation. It was recognized that this horizon has been filled with products of a big object collision with Earth. The age of the manganese-iron intercalation was determined by potassium-argon (K-Ar) dating of illites to be (89.3±1.2) Ma. Similar age, (85.2±0.6) Ma, was found for the post-impact glass from the Boltysh crater in Ukraine. It was concluded that the formation of this intercalation was synchronous with the Boltysh crater formation at the Cenomanian/Turonian boundary. The research for the K-Ar age of the crater creation in Logoisk (Belarus) established its formation to (124.2±1.2) Ma ago.
Do We Need Asymmetric Organocatalysis?
Authors: Dalko Peter I.
Published: July 2007

Asymmetric organocatalysis is a 'fast lane' of the chemical highway: the progress in the last decade is simply spectacular. This introductory article summarizes basic principles, historical background, and discusses basic catalyst classes and reaction types.
Catalytic, Asymmetric Inverse Electron Demand Hetero Diels-Alder Reactions of o-Benzoquinone Derivatives and Ketene Enolates
Authors: Paull Daniel H. , Wolfer Jamison , Grebinski James W. , Weatherwax Anthony , Lectka Thomas
Published: July 2007

We present an array of [4+2] cycloaddition reactions between ketene enolates, catalytically derived from acid chlorides and cinchona alkaloid nucleophilic catalysts in the presence of stoichiometric base, and o-benzoquinone derivatives. These cycloaddition reactions proceed with
excellent stereochemical control (up to >99% ee). In fact, for both the o-benzoquinone imide and the o-benzoquinone diimide manifolds, these Diels-Alder reactions occurred with uniformly >99% ee. The wide scope of this methodology provides access to a diverse
range of biologically and synthetically useful chiral products, including ?-hydroxyesters, non-natural ?-amino acids, quinoxalinones, and many others, all with remarkable, catalytic control of regio- and stereochemistry.
(S)- and (R)-5-Pyrrolidin-2-yl-1H-tetrazoles: Enantiomeric Organocatalysts of Broad Utility in Organic Synthesis
Authors: Longbottom Deborah A. , Franckevičius Vilius , Ley Steven V.
Published: July 2007

This mini-review concerns the broad application of (S)- and (R)-5-pyrrolidin-2-yl-1H-tetrazoles as organocatalysts. A summary of methods for their synthesis is followed by a discussion of the general reaction mechanism and subsequent analysis of each reaction type for
which they have proved to be efficient catalytic species. Where relevant, a comparison is made with other organocatalysts in similar asymmetric reaction processes.
The Amino Thiourea-Catalyzed Asymmetric Nucleophilic Reactions
Authors: Takemoto Yoshiji , Miyabe Hideto
Published: July 2007

Bifunctional amino thiourea-catalyzed asymmetric additions of several nucleophiles into electron-deficient unsaturated compounds such as nitroolefins, ?,?-unsaturated imides, imines, and azodicarboxylates are described. We discovered that bifunctional thioureas bearing a
tertiary amino group significantly accelerated several nucleophilic addition reactions of active methylene compounds to electron-deficient double bonds. In these reactions, a strong hydrogen-bonding ability of the thiourea moiety as well as an appropriate Brønsted basicity of the tertiary
amine is crucial for high enantioselectivity. This dual activation of both nucleophiles and electrophiles by the bifunctional thiourea expanded the applicability of the thiourea-catalyzed enantioselective reaction. In addition, these organocatalyzed asymmetric reactions were successfully applied
to the concise asymmetric synthesis of natural products and medicinal candidates such as epibatidine, baclofen, and CP-99,994.
Gender and Transportation Access among Community-Dwelling Seniors
Authors: Dupuis Josette , Weiss Deborah R. , Wolfson Christina
Published: July 2007

Purpose:This study estimates the prevalence of problems with transportation in a sample of community-dwelling seniors residing in an urban setting and investigates the role that gender plays in the ability of seniors to remain mobile in their communities.

Design and Methods:Data collected as part of a study assessing the prevalence and consequences of unmet needs for community-based services in a random sample of 839 elderly aged 75 years and older were employed in bivariate and multivariable analyses.

Results:The prevalence of problems with transportation was 23 per cent, with 33 per cent of females and 10 per cent of males categorized as having problems with transportation. Of those subjects categorized as having problems with transportation, 88 per cent were women. In addition to being predominantly women, those who reported problems with transportation were older, in poorer health, and had lower income and income satisfaction.

Implications:Problems with transportation are an important issue facing seniors; women, in particular. These results highlight the differences in aging as experienced by women and men with respect to social effects, needs, and the significance attached to the experience.
The low frequency of defective TPMT alleles in Turkish population: A study on pediatric patients with acute lymphoblastic leukemia
Authors: Tumer Tugba Boyunegmez , Ulusoy Gulen , Adali Orhan , Sahin Gurses , Gozdasoglu Sevgi , Arinç Emel
Published: July 2007

6‐Mercaptopurine (6MP) is an essential anticancer drug used in the treatment of childhood acute lymphoblastic leukemia (ALL). Thiopurine methyltransferase (TPMT) polymorphisms are the major determinants of interindividual differences in the severe toxicity or efficacy of 6MP. Four variant alleles, TPMT*2, TPMT*3A, TPMT*3B, and TPMT*3C, are responsible over the 80% of low or undetectable enzyme activity. The frequencies of these variants were investigated among 106 children with ALL in Turkish population. TPMT*3A and TPMT*3C were the only deficiency alleles detected in Turkish population with an allele frequency of 0.9% for both. While *3C allele frequency in Turkish population was found to be very similar to Asian and other Caucasian populations, *3A allele frequency was significantly (P < 0.05) lower. So far, studies showed that the genetic polymorphisms of other drug metabolizing enzymes like CYP2E1, CYP1A1, GSTM1/ T1 in Turkish population were similar to Caucasian populations. However, we found that the distribution of TPMT polymorphisms in Turkish population was significantly lower than those in other Caucasians like British, French, and Italian whereas the distributions of TPMT variants were found to be very similar to Kazak population which is also Caucasian in ethnic origin. In this study, the clinical histories of the patients in the sample population were also examined, retrospectively. The patients with heterozygous or homozygous mutant genotypes had developed severe neutropenia and infection during 6MP therapy. The study provides the first data on the frequency of common TPMT variants in the Turkish population, based on analysis of pediatric patients with ALL. Am. J. Hematol. 82:906–910, 2007. © 2007 Wiley‐Liss, Inc.
Reduced intensity compared with high dose conditioning for allotransplantation in acute myeloid leukemia and myelodysplastic syndrome: A comparative clinical analysis
Authors: Flynn Catherine M. , Hirsch Betsy , DeFor Todd , Barker Juliet N. , Miller Jeffrey S. , Wagner John E. , Blazar Bruce R. , Burns Linda J. , MacMillan Margaret L. , Arora Mukta , Weisdorf Daniel
Published: July 2007

We evaluated the efficacy of hematopoietic stem cell transplantation (HSCT) using reduced intensity (RI) vs. myeloablative (MA) conditioning for patients with acute myeloid leukemia (AML) and myelodysplastic syndrome. Thirty two patients (median age 54) who underwent a RI HSCT (2000–2003) were compared with 187 patients (median age 39) who received a MA transplant (1990–2003). Neutrophil engraftment was more rapid in the RI group (median 11.5 vs. 21 days). Platelet recovery was similar and graft failure was infrequent. The incidence of graft‐versus‐host disease (GVHD) and treatment‐related mortality was similar though relapse was more frequent after RI conditioning (RR 2.2 [95% CI = 1.1–4.6] P = 0.03). At 2 years, disease‐free survival (DFS) (31% vs. 30%, P > 0.1) and overall survival (33% vs. 35%, P > 0.1) were comparable between RI and MA groups, respectively. We suggest that RI allografts can yield satisfactory DFS both for older as well as younger patients with pre‐existing comorbidities, who are ineligible for MA allografts. Advances in GVHD management and new approaches for relapsed or refractory disease are necessary to improve these outcomes. Am. J. Hematol. 82:867–872, 2007. © 2007 Wiley‐Liss, Inc.
Autosomal recessive mental retardation syndrome with anterior maxillary protrusion and strabismus: MRAMS syndrome
Authors: Basel‐Vanagaite Lina , Rainshtein Limor , Inbar Dov , Gothelf Doron , Hennekam Raoul , Straussberg Rachel
Published: July 2007

We report on a family in whom the combination of mental retardation (MR), anterior maxillary protrusion, and strabismus segregates. The healthy, consanguineous parents (first cousins) of Israeli‐Arab descent had 11 children, 7 of whom (5 girls) were affected. They all had severe MR. Six of the seven had anterior maxillary protrusion with vertical maxillary excess, open bite, and prominent crowded teeth. None of the sibs with normal intelligence had jaw or dental anomalies. The child with MR but without a jaw anomaly was somewhat less severely retarded, had seizures and severe psychosis, which may point to his having a separate disorder. Biochemical and neurological studies, including brain MRI and standard cytogenetic studies, yielded normal results; fragile X was excluded, no subtelomeric rearrangements were detectable, and X‐inactivation studies in the mother showed random inactivation. We have been unable to find a similar disorder in the literature, and suggest that this is a hitherto unreported autosomal recessive disorder, which we propose to name MRAMS (mental retardation, anterior maxillary protrusion, and strabismus). © 2007 Wiley‐Liss, Inc.
Osseous dysplasia with severe short stature, multiple dislocations, and delayed bone age: Report on a second Lebanese patient
Authors: Mégarbané André
Published: July 2007

We describe a young girl with severe pre‐ and postnatal short stature, bilateral dislocation of hips, knees and elbows, and right clubfoot. Skeletal investigations disclosed an anisospondyly, the absence of ossification of the odontoid apophysis and of fusion of the neural arches of the cervical vertebrae, abnormal L3 and L4 vertebrae, partial agenesis of the coccyx, abnormal and sub‐luxated radial heads, bilateral dislocation of the hips, dysplastic acetabulae, pseudoacetabulae, hypoplasia of the femoral heads, short femoral necks, short long bones with thin diaphyses, widening of the medullary canal and thinning of the cortical one, slightly enlarged metaphyses, and diffuse osseous demineralization. Bone age was delayed. The girl's parents are first cousins. Differential diagnoses are discussed and the possibility is raised that this might be a second patient with clinical features indicating an entity recently described in a young Lebanese boy [Mégarbané and Ghanem (2004); Am J Med Genet Part A 130A: 107–109]. A clinical follow‐up of the latter patient is also reported. © 2007 Wiley‐Liss, Inc.
Degradation of poly(L‐lactide) films under ultraviolet‐induced photografting and sterilization conditions
Authors: Janorkar Amol V. , Metters Andrew T. , Hirt Douglas E.
Published: July 2007

The degradation of polymers under ultraviolet (UV) irradiation has been a great concern for biomaterial and agricultural applications. The major objective of this research was to study the effect of UV irradiation on the representative bulk and surface properties of poly (L‐lactide) (PLA) films. Two UV sources with different spectral outputs and intensities were chosen so that one of them could be used for surface modification and the other could be used for UV sterilization of the PLA films. The results established that the molecular weight of PLA decreased significantly during irradiation from the photografting lamp under atmospheric conditions. Irradiation through a Pyrex container was shown to minimize polymer degradation during UV exposure from the photografting lamp. The PLA films UV‐irradiated under the sterilization lamp for 12 h revealed a similar reduction in the molecular weight and no change in the surface hydrophilicity. However, significantly less photodegradation was observed under the sterilization lamp when the samples were held in a Pyrex container. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Der Gravitations‐Stoß
Authors: Thüring B.
Published: July 2007

Die folgenden Ausführungen wollen ein Beitrag zum Problem des Zusammenstoßes von Galaxien sein. Der einfache Fall zweier Systeme von je zwei sich in Kreisbahnen umeinander bewegenden kugelförmigen Massen, welche in zunächst großer gegenseitiger Entfernung aufeinander zufliegen und im „Zusammenstoß”︁ sich durchdringen, wird numerisch streng integriert. Es wird gezeigt, daß die Bewegung der beiden Systeme trotz alleiniger Gravitationswirkung den Gesetzen des physikalischen Stoßes gehorcht. Nach dem „Gravitations‐Stoß”︁ bewegen sich die beiden Systeme in geänderten Richtungen und mit geänderten energetischen Zuständen weiter. Das einfache Modell wird schließlich galaktischen Größenverhältnissen angepaßt.
Strahlenoptische Ausbreitung in Medien mit statistisch verteilten Inhomogenitäten II. Streuung in kleine Winkelbereiche
Authors: Scheffler H.
Published: July 2007

Die Verteilung der Richtungen und seitlichen Verschiebungen der Strahlen eines ursprünglich parallelen Bündels nach Durchlaufen eines turbulenten Mediums mit unregelmäßigen Schwankungen des Brechungsindex wird für den Fall kleiner Ablenkungswinkel hergeleitet für Medien mit (a) konstantem mittlerem Brechungsindex und homogener Turbulenz, sowie (b) langsam veränderlichem mittlerem Brechungsindex und nichthomogener Turbulenz.
Über den Zusammenhang zwischen der Anzahl der extragalaktischen Objekte und der scheinbaren Helligkeit (Mitteilungen des Astrophysikalischen Observatoriums Potsdam Nr. 71)
Authors: Mattig W.
Published: July 2007

Im Rahmen der relativistischen Kosmologie wird für den Fall des verschwindenden kosmologischen Gliedes A ein strenger Zusammenhang zwischen der Anzahl der extragalaktischen Objekte und der bolometrischen Helligkeit angegeben.
Visuelle Beobachtungen des Mars 1954 und 1956
Authors: Heintz W. D.
Published: July 2007

Beobachtungen aus zwei Periheloppositionen des Mars (1956 auch mit Filtern) werden zu einer Karte zusammengestellt und dazu Veränderungen während des Beobachtungszeitraumes, die Südpolumgebung, Wolken, Schleier und Polkappen gesondert erwähnt. Die Marskanäle sind als großenteils reell, wenngleich nicht unbedingt als sehr schmale scharfe Gebilde anzusprechen.
Über die Erkennbarkeit unaufgelöster Doppelsterne aus dem spektralen Intensitätsverlauf (Mitteilungen des Astrophysikalischen Observatoriums Potsdam Nr. 73)
Authors: Lamla E.
Published: July 2007

Mit Hilfe der aus spektralphotometrischen Beobachtungen von Einzelsternen gewonnenen spektralen Intensitätsverläufe des verschmierten Kontinuums verschiedener Spektraltypen und Leuchtkraftgruppen im Wellenlängenbereich 300 ≦ λ ≦ 1060 mμ werden rechnerisch Intensitätsverteilungen von Doppelsternen ermittelt, um sie mit denjenigen von Einzelsternen zu vergleichen. Dadurch soll festgestellt werden, ob und in welchem Spektralbereich auf Grund einer Spektralphotometrie der kontinuierlichen Strahlung unaufgelöster Doppelsterne ihr Doppelsterncharakter erkannt werden kann. Es zeigt sich, daß dies in extremen Wellenlängenbereichen möglich sein wird. Abschließend werden einige beobachtete Intensitätsverteilungen von Doppelsternen diskutiert, insbesondere die des Bedeckungsveränderlichen ϵ Aur.
Über die spektrale Intensitätsverteilun und die Leuchtkraftverteilung von Sternsystemen
Authors: Lamla E.
Published: July 2007

Mit Hilfe der aus vorliegenden Spektralphotometrien gewonnenen Standard‐Intensitätsverteilungen von Einzelsternen verschiedener Spektraltypen und Leuchtkraftgruppen werden die Intensitätsverteilungen von Sternsystemen – Kugelhaufen und elliptische Nebel – berechnet und mit den vorliegenden Beobachtungen verglichen. Die erforderlichen Leuchtkraftverteilungen (LKV) werden aus Extrapolationen der aus der Beobachtung bekannten LKV der hellsten Sterne der Kugelhaufen (Population II) unter der Bedingung gewonnen, daß mit den LKV die beobachteten Daten über Gesamtmasse und Gesamtleuchtkraft dieser Systeme durch die Rechnung gut wiedergegeben werden können. Zur Ermittlung der LKV der E‐Nebel muß eine Annahme über die Form der Farbenhelligkeitsdiagramme gemacht werden. Es gelingt, die Intensitätsverteilungen der E‐Nebel mit LKV zu ermitteln, die sowohl der reinen Population II als auch der „alten”︁ Population I entsprechen. Insbesondere tritt in der mit Sternen der Population I berechneten Intensitätsverteilung ein Balmersprung auf, der bei Annahme der reinen Population II nicht zu erwarten ist. Dadurch ist u. U. die Möglichkeit gegeben, auf Grund des Intensitätsverlaufes im UV entscheiden zu können, zu welcher Population die Sterne eines E‐Nebels zu zählen sind. Neben der Darstellung der beobachteten Intensitätsverläufe durch die Rechnung werden auch die anderen integralen Zustandsparameter der Sternsysteme bestimmt. Entsprechende Rechnungen sind für das lokale System der Sterne der näheren Sonnenumgebung durchgeführt worden.
Über das Turbulenzspektrum der thermischen Konvektion in der Sonne
Authors: Schmeidler F.
Published: July 2007

Das Turbulenzspektrum einer infolge thermischer Instabilität konvektiven Gasmasse weicht vom Spektralgesetz der hydrodynamischen Turbulenz ab, weil das Spektrum wesentlich durch die thermische Auftriebskraft bestimmt wird. Der Mechanismus der Konvektion bringt es mit sich, daß sich aus einem aufsteigenden heißen Element durch Wärmeabgabe an die Umgebung ein größeres Element bildet, aus diesem wieder ein noch größeres etc. Der Durchmesser der größten Elemente ist ungefähr gleich der Skalenhöhe der Temperaturänderung. Die Geschwindigkeit der Elemente ist proportional zum Quadrat ihres Durchmessers. Für die kleinsten Elemente ergibt sich das hydrodynamische Spektralgesetz als Grenzfall. Die Energiedissipation kann gegenüber der gesamten Turbulenzenergie vernachlässigt werden, solange die größten Elemente sich in guter Näherung adiabatisch verhalten.
Programmgesteuerte Berechnung von Librationsbahnen
Authors: Thüring B.
Published: July 2007

Auf Grund von programmgesteuerten Rechnungen an der Univac‐Factronic in Frankfurt a. M. wird für das ebene problème restreint die Existenz von Doppel‐Librationen um die Librationspunkte L4 und L5 gezeigt. Eine Untersuchung der schon früher entdeckten spiralartigen Form der Librationsbahnen lehrt ferner, daß die Librationen als Übergangsbewegungen von äußeren zu inneren Bahnen des gestörten Körpers (bzw. umgekehrt) anzusehen sind und daß die Anzahl der Übergangslibrationen von dem Massenverhältnis der beiden massigen Körper abhängt. Für die Trojaner des Sonnen systems ergibt sich (unter gewissen Voraussetzungen) eine Minimalanzahl von 22 (einfachen) Librationen.
Untersuchungen über SX Cassiopeiae. I (Mitteilungen des Astrophysikalischen Observatoriums Potsdam Nr. 79)
Authors: Günther O.
Published: July 2007

Beobachtungen des Verfassers werden mit den visuellen Beobachtungen von Dugan zu einer visuellen Normallichtkurve vereinigt. Die verbesserte Periode ist 36d.56732, ein neues Normalminimum J. D. 243 3963d.281.

Es wird gezeigt, daß Bahnen von bewegten Gasmassen, die für ein vereinfachtes Modell von SX Cas berechnet wurden, weitgehend den spektrographischen Beobachtungen entsprechen.
Zum Stoß schneller interstellarer Wasserstoffwolken
Authors: Zimmermann H.
Published: July 2007

Es wird der Zusammenstoß zweier interstellarer Wolken mit einer Relativgeschwindigkeit von 100 km/sec und die daran sich anschließende Abkühlung der auf etwa 105°K erhitzten Materie betrachtet. Dazu werden die auftretenden Elementarprozesse unter Voraussetzung reinen Wasserstoffes einzeln diskutiert und die erforderlichen Wirkungsquerschnitte zum Teil neu berechnet. Es zeigt sich, daß in verhältnismäßig kurzer Zeit die Temperatur stark abnimmt, während der Ionisationsgrad des Wasserstoffs einem Maximum zustrebt und dann nur langsam wieder kleiner wird. Die räumliche Dichte hingegen steigt stetig an.
Strahlenoptische Ausbreitung in Medien mit statistisch verteilten Inhomogenitäten III. Strahlenverlauf und Intensitätsschwankungen als MARKOFF‐Prozeß (Mitteilungen des Astrophysikalischen Observatoriums Potsdam Nr. 85)
Authors: Scheffler H.
Published: July 2007

Der Verlauf der Richtungen und seitlichen Verschiebungen von Strahlen beim Durchsetzen eines Mediums mit statistisch verteilten Brechungsindexschwankungen wird als vierdimensionaler MARKOFF‐Prozeß behandelt. Die Verteilung der Streuwinkel und Strahlversetzungen ist als Übergangswahrscheinlichkeit des Prozesses Lösung der KOLMOGOROFF‐Gleichung und wird für den Fall kleiner Strahlablenkungen ermittelt. Hieran schließt sich die in ähnlicher Weise mögliche Gewinnung der Verteilung der Intensitätsschwankungen am Ende der turbulenten Schicht für den Fall kleiner Streuwinkel und die Berechnung der Korrelationsfunktion der räumlichen Struktur der Intensitätsschwankungen in Ebenen senkrecht zur Einfallsrichtung der Strahlen. Abschließend wird der Übergang zu einem beliebigen anisotropen Feld der Brechungsindexschwankungen und dessen Spektraldarstellung an Stelle der Beschreibung durch Korrelationsfunktionen ausgeführt.