bluuebunny/crossref_metadata_2025 huggingface dataset:
Amines by Reduction
Authors: Cartolano Anthony R. , Vedage Gamini A.
Published: May 2005

Amines are derivatives of ammonia in which one or more of the hydrogens is replaced with an alkyl, aryl, cycloalkyl, or heterocyclic group. When more than one hydrogen has been replaced, the substituents can either be the same or different. Amines are classified as primary, secondary, or tertiary depending on the number of hydrogens that have been replaced. Many different types of nitrogen‐containing compounds can be reduced to amines. In practice, however, nitriles or nitro compounds are usually used because they are the most easily obtained starting materials. There are several commercial processes for reducing nitro or nitrile groups to amines. Most large volume aromatic and aliphatic amines are made by continuous high pressure catalytic hydrogenation. Nitro compounds can also be reduced in good yields with iron and hydrochloric acid in the Bèchamp process. Aromatic amines are usually made by hydrogenating the corresponding nitro compound, whereas the aliphatic amines generally start with the corresponding nitrile. In the Bèchamp process, nitro compounds are reduced to amines in the presence of iron and an acid. This is the oldest commercial process for preparing amines, and is still used in the dyestuff industry. The method of reducing aromatic nitro compounds with divalent sulfur is known as Zinin reduction. This reaction is carried out in a basic media using sulfides, polysulfides, or hydrosulfides as the reducing agent. Amines, nitro compounds, nitriles, and the various solvents and reagents used in the preparation of amines by reduction vary widely in the hazards they may pose. Some of these materials are acutely toxic by ingestion, inhalation, or absorption through the skin. Others are skin irritants or sensitizers. Still others, by chronic exposure, may cause damage to organs such as the liver or may be carcinogenic. No general rules can govern their safe use in all cases. Regulations governing the safe handling and shipping of amines are given in U.S. Department of Transportation publications. Specific information on safe handling and hazards can be found in the Material Safety Data Sheet for a given material.
Fluid Mechanics
Authors: Tavoularis Stavros
Published: May 2005

Fluid mechanics encompasses the description and prediction of the motion of fluids. The physical principles and associated mathematical equations that are the basis of theoretical study are presented and the types of approximations employed for the study of different flow phenomena are explained. Special flow configurations and phenomena discussed include internal flows, flows near solid walls, flows past immersed bodies, free shear flows, compressible flows, flow instability and secondary flows, flows through porous media, non‐Newtonian flows and two‐phase flows. Essentials of computational fluid dynamics and flow measurement instrumentation and techniques are also presented.
Hydroxycarboxylic Acids
Authors: Datta Rathin
Published: May 2005

Hydroxycarboxylic acids are an important group of chemicals, with several members that are commercially manufactured in large volumes and have a wide range of applications. Two α‐hydroxycarboxylic acids, lactic and glycolic, and a derivative of γ‐hydroxycarboxylic acid γ‐butyrolactone are discussed in detail because of their relative commercial importance, both current and future. General classes of reactions that these acids undergo are also discussed, with specific examples of those reactions that are or could become commercially important.

Current manufacturing processes for lactic and glycolic acids and γ‐butyrolactone are briefly outlined, with estimates of the production volume and market size for various applications. For lactic acid production and manufacture of its derivatives for biodegradable polymers, new processes are emerging, and some of the recent patents and emerging technologies are highlighted. Some of the important uses of hydroxycarboxylic acids are related to environmentally friendly products and processes such as biodegradable plastics for consumer products and nontoxic and easily degradable solvents, cleaning agents, plasticizers, etc. The emergence of new technologies for efficient and economical manufacture of these chemicals, combined with these product opportunities, could make these hydroxycarboxylic acids very large‐volume chemicals of global commercial importance.
Hydrogen Chloride
Authors: Hisham Mohamed W. M. , Bommaraju Tilak V. ,   Updated by Staff
Published: May 2005

Hydrogen chloride, a gas at ambient temperature and pressure, is very soluble in water. Hydrogen chloride can be produced by direct reaction of the elements, by reaction of metal chlorides and acids, and as a by‐product from many chemical manufacturing processes such as those for chlorinated hydrocarbons. Over 90% of the hydrogen chloride produced in the United States is as a by‐product from various chemical processes. HCl is produced as a by‐product in the manufacture of chlorofluorohydrocarbons, aliphatic and aromatic hydrocarbons, production of high surface area silica, and the manufacture of phosphoric acid and esters of phosphoric acid. Crude by‐product HCl is generally contaminated with impurities of the process. A wide variety of techniques are employed to treat the HCl streams to obtain either anhydrous HCl or hydrochloric acid. Technologies have been developed for burning or pyrolyzing waste organics and recovering the chlorine values as hydrogen chloride.

Hydrogen chloride and its aqueous solution, muriatic acid, find application in many industries. In general, anhydrous HCl is consumed for its chlorine value, whereas aqueous hydrochloric acid is often utilized as a nonoxidizing acid, in metal‐cleaning operations, chemical manufacturing, petroleum well activation, and the production of food and synthetic rubber. Most of the HCl produced is consumed captively either in integrated operations, eg, chlorinated methane plants, or in separate HCl‐consuming operations at the same location.
Ocean Raw Materials
Authors: Cruickshank Michael J.
Published: May 2005

Inorganic raw materials are defined as any mineral deposit found in the marine environment. The ocean is host to a variety and quantity of inorganic raw materials equaling or surpassing the resources of these materials available on land. The mineral resources include industrial minerals, mineral sands, phosphorites, metalliferous oxides, hydrothermal metalliferous sulfides, and dissolved minerals, as well as geothermal resources, gas hydrates precious corals, and some algae. The resources are classified as unconsolidated, consolidated, or fluid materials that are chemically enriched in certain elements and are found in or on the seabeds of the continental shelves and ocean basins. With few exceptions these materials are similar to traditional mineral deposits on land. A significant source of minerals for sustainable recovery in the future may be ocean waters, which include nearly all the known elements in some degree of solution. Commercialization of production of dissolved minerals from seawater is limited to freshwater, magnesium, magnesium compounds, salt, bromine, and heavy water, ie, deuterium oxide. There are four basic methods of mining solid minerals: scraping the surface, excavating a pit or trench, removal through a borehole in the form of a slurry or fluid, and tunneling into the deposit. An apparently significant advantage to recovery of mineral raw materials from the marine environment is the benign effects of these activities when compared to the recovery of the same materials from land.
Rubber Compounding
Authors: Rodgers Brendan , Waddell Walter H. , Solis Scott , Klingensmith William
Published: May 2005

Rubber compounding is the complex, multidisiplinary science of selecting and blending the optimum combination of elastomer and other ingredients that meet the performance, processing, environmental, and cost requirements for rubber goods made and used in commerce. Chemical and physical properties of the wide variety of elastomers and ingredients available in making rubber goods are provided. Vulcanization, oils, plasticizers, general compounding, curing, fillers, latex, and testing are discussed.
Silk
Authors: Kaplan David L.
Published: May 2005

Silks are naturally spun fibrous proteins most often associated with the silkworm and spiders. Silk fibers are unusual in combining strength, toughness, and compressibility. The proteins are characterized primarily by a β‐sheet secondary structure consisting of a highly crystalline region as well as regions of lower crystallinity. Silkworm cocoon fibers have been used in textiles for thousands of years. Spider silk, of which there are many different types, has not been domesticated. Water‐soluble silk proteins are synthesized and stored in the silk glands until spun into fibers, at which point they become insoluble in water. The spinning process is regulated by the organism and involves the extrusion of the soluble silk in a liquid crystalline state through spinnerets. Silks are stable to approximately 230°C. Membranes have been formed from silks that provide a useful means to explore secondary structure and to entrap enzymes. Worldwide production of silkworm silk for textiles is expected to increase. Future applications depend on the success of biotechnology to provide adequate production levels of specifically tailored silk compositions.
Herbicides, Biotechnology
Authors: Duke Stephen O. , Scheffler Brian E. , Boyette C. Douglas , Lydon John , Oliva Anna
Published: May 2005

Biotechnology can be used to enhance the management weeds in several ways. Crops have been made resistant to herbicides by inserting transgenes that impart herbicide resistance into the plant genome. Glyphosate‐, glufosinate‐, and bromoxynil‐resistant crops are commercialized in North America. This technology has been highly successful, transforming weed management in several major crops. Selection for mutations that impart herbicide resistance to crops has also been successfully used to generate herbicide‐resistant crops. There are several living microbial products for the biocontrol of weeds. These agents have not been very successful, but work is being conducted to improve them with biotechnology methods. The use of crops that produce their own herbicides (allelopathy) has been even less successful. Biotechnological approaches are being used to generate crops that can poison weeds with less or without synthetic chemical inputs. Research on natural phytotoxins from plants (allelochemicals) has also provided lead compounds for herbicide discovery.
Self‐Decomposable Distributions
Authors: Kotz Samuel
Published: May 2005

The basic definition of self‐decomposable distributions is presented and a brief mention of their applications is made.
Dependence,Kent–O'Quigley Measure
Authors: Nadarajah Saraless , Kotz Samuel
Published: May 2005

A dependence measure attributable to Kent and O'Quigley and some of its properties are discussed.
Elliptical Distributions, Extremal Type
Authors: Nadarajah Saraless , Kotz Samuel
Published: May 2005

Two new elliptical distributions—based on the Gumbel and Fréchet extreme value distributions—are discussed.
Engineering Statistics
Authors: Vardeman Stephen B.
Published: May 2005

In this entry, we seek to put into perspective some of the ways in which statistical methods contribute to modern engineering practice.
International Monetary Fund (
IMF
)
Authors: Carson Carol S.
Published: May 2005

The IMF acts as a center for the collection and exchange on macroeconomic statistics for its near universal membership. These statistics are used to assist the IMF in economic consultations aimed at fostering international financial stability. Activities are closely coordinated with other international organizations. Statistical activities also include the development of macroeconomic accounting standards, dissemination standards, assessments of statistical capacity, and technical advice.
Kriging, Simple Indicator
Authors: Solow Andrew
Published: May 2005

Simple indicator kriging is a method for interpolation in a binary random field. The method is based on estimates of the first two moments of the field. It has been shown to perform well when the binary field is formed by clipping a Gaussian random field.
Mean,Searls' Estimators of
Authors: Nadarajah Saraless , Kotz Samuel
Published: May 2005

Some extensions of Searls' estimator of population mean are discussed.
Multivariate Symmetry and Asymmetry
Authors: Serfling Robert J.
Published: May 2005

Univariate symmetry has interesting and diverse forms of generalization to the multivariate case. Here several leading concepts of multivariate symmetry—spherical, elliptical, central, and angular—are examined and various closely related notions discussed. Methods for testing the hypothesis of symmetry and approaches for measuring the direction and magnitude of skewness are reviewed.
Multivariate Uniformity,
L
iang–
F
ang–
H
ickernell–
L
i Test of
Authors: Nadarajah Saraless , Kotz Samuel
Published: May 2005

A test of multivariate uniformity attributable to Liang, Fang, Hickernell, and Li is discussed.
P
earson Type
VII
Distribution on the Unit Sphere
Authors: Nadarajah Saraless , Kotz Samuel
Published: May 2005

A new distribution referred to as the Pearson type VII distribution is introduced and some of its properties discussed.
Ranking and Selection Procedures
Authors: Panchapakesan S.
Published: May 2005

We first provide a brief account of the beginnings and the early developments in the field of ranking and selection theory. The basic formulations and generalization of goals are then discussed. This is followed by a brief summary of subsequent developments.
Justice,Rawlsian Theory of
Authors: Senn Stephen
Published: May 2005

The contribution of American philosopher John Rawls'sTheory of Justiceto the ethics of social and economic distribution is reviewed briefly. Parallels with insurance are drawn. Its relevance to decision‐making for groups of individuals is considered, and an application to clinical trials is briefly considered. Some problems with the theory are touched on.
Spacings, Linear Combinations of
Authors: Huffer Fred W. , Lin Chien‐Tai
Published: May 2005

Problems involving the distribution of linear combinations of spacings occur in many areas of statistics. This article gives expressions for the density and distribution function of an arbitrary linear combination of spacings. General methods are also presented for computing the distribution of the maximum or minimum of any finite collection of linear combinations of spacings. When the coefficients of the linear combinations are rational, these methods can be implemented on computer algebra systems to produce exact symbolic expressions for the distributions. These expressions can be used to compute numerical answers accurate to any required degree of precision.
Self‐Selected Samples
Authors: Rutherford Andrew
Published: May 2005

The term “Self‐Selected Samples” is explained. The nature of selection with respect to such samples is described, its relation to other sampling techniques is considered briefly and a distinction between strong and weak selection is made. Strong self‐selected samples are not representative of the population of interest and may very likely differ on pertinent factors. Hence, there are serious problems in generalizing inferences from self‐selected samples to their populations. A very brief outline is provided for three statistical approaches to problems with self‐selected samples: the use of covariates, mixture modeling, and selection modeling.
MonteCarlo Methods
Authors: Gentle James E.
Published: May 2005

Monte Carlo simulation is one of the most important tools in all fields of science. Monte Carlo methods are experiments that use samples of numbers that appear to be random, although the numbers are generated by deterministic computer algorithms. These “pseudorandom” samples can be used in solving a wide range of problems, including both deterministic problems such as evaluating a definite integral and problems in which there is a random component such as studying and comparing the performance of statistical procedures under various assumptions about the underlying distribution.
Communications and Radar, Detection in
Authors: Varshney Pramod K. , Viswanathan R.
Published: May 2005

Signals arriving at a communication or a radar receiver are stochastic in nature and therefore many optimum processing techniques have been developed on the basis of statistical models for these signals. Here, we describe various signal detection procedures that are employed in communications and radar systems. Fundamentals of discrete‐time and continuous‐time matched filtering are introduced. Applications to demodulation of digital modulation signals, single and multiple‐pulse radar target detection, constant false alarm rate processing for radar, and netted radar systems are presented.
Banking, Statistics in
Authors: Hand David J.
Published: May 2005

Mathematical models in the investment banking and financial markets sectors have been the focus of concentrated research effort for several decades, but the application of statistical methods is a relatively new development. In contrast, in retail banking, statistical models have been applied for over 40 years, though of late their level of sophistication and complexity has increased dramatically. Both developments are a result of increased computer power. A large range of types of statistical tools are being applied, but especially tools concerned with predicting default risk at various levels. Given the increased competition, the current harsh economic climate, and toughening legislative environment, it seems likely that the demand for objective statistical methods will become even greater in the future.
Telephone Survey Methodology
Authors: Link Michael W.
Published: May 2005

Telephone survey methods are widely used for the cost‐effective and timely collection of data in sample surveys. Although telephone survey designs can vary on a number of dimensions, including how populations are sampled, technology employed, and protocol followed, nearly all involve issues of sampling design, questionnaire development, case management, interviewer training, quality control monitoring, and data processing. The mode does face a number of challenges, including the increase in the sheer volume of telephone numbers, the growing use of call screening devices and cellular telephones, and the proliferation of telemarketing.
Stochastic Resonance
Authors: Bulsara Adi R.
Published: May 2005

Noise is usually considered a nuisance or a laboratory curiosity, better avoided, in most practical applications. However, certain nonlinear dynamic systems in nature (the most ubiquitous of these being, of course, the central nervous system) appear to utilize the background noise as an aid to the analysis of low‐intensity signals embedded in the noise floor. A phenomenon known as stochastic resonance (SR) has been studied in the context of this amplification of weak signals in a noise background; the effect is only one of a plethora of diversified behavior that is displayed by nonlinear dynamic systems in the presence of noise, and can actually lead to an energy transfer from the noise floor to the signal feature (in the response), under the appropriate operating conditions.
Tukey,JohnWilder
Authors: Brillinger David R.
Published: May 2005

John Tukey was one of the great statistical scientists of the twentieth century. He introduced algorithms, concepts, language, philosophy, and techniques. He made important contributions to government, to industry and to science.
Linear Sensitivity Measure
Authors: Balakrishnan N. , Chandrasekar B.
Published: May 2005

In this article, we first present the linear sensitivity measure as introduced by Tukey [7]. Then, we present some properties of it established by Nagaraja [5] and also describe the multiparameter version of it as proposed by Chandrasekar and Balakrishnan [2]. Finally, we present some illustrative examples.
Statistical Signal Processing
Authors: Kannan Nandini , Kundu Debasis
Published: May 2005

Statistical signal processing is an important area of research with extensive applications in the fields of communication theory, array processing, seismology, and medical diagnosis. The goal of signal processing is to recover characteristics of the underlying process from observed data. The random nature of the signals underscores the need for statistical techniques in model formulation, estimation, and data analysis. A brief discussion of two models that have been widely studied in the signal processing literature is provided. In addition, different methods of estimation are presented, and some unique characteristics of these models are highlighted.
Lead
Authors: Sutherland Charles A. , Milner Edward F. , Kerby Robert C. , Teindl Herbert , Melin Albert , Bolt Hermann M.
Published: May 2005

The article contains sections titled:

1.

Introduction

2.

Properties

3.

Occurrence

4.

Production

4.1.

Ore Concentration

4.2.

Smelting

4.2.1.

Sintering Reduction Process

4.2.1.1.

Downdraft Sintering

4.2.1.2.

Updraft Sintering

4.2.1.3.

Products of Sinter Roasting

4.2.2.

Reduction in the Blast Furnace

4.2.2.1.

Process Description

4.2.2.2.

Lead Blast Furnaces

4.2.2.3.

Products of the Lead Blast Furnace

4.2.2.4.

Imperial Smelting Process

4.3.

Roast Reaction Processes

4.4.

Direct Smelting Reduction Processes

4.4.1.

Air Flash Smelting

4.4.2.

Oxygen Flash Smelting

4.4.2.1.

Kivcet Process

4.4.2.2.

Boliden Kaldo Process

4.4.2.3.

Outokumpu Process

4.4.3.

Air ‐ Slag Bath Smelting, the Isasmelt Process

4.4.4.

Oxygen ‐ Slag Bath Smelting, QSL Process

4.5.

Other Lead Processes

5.

Refining of Lead Bullion

5.1.

Pyrometallurgical Refining

5.1.1.

Decoppering

5.1.2.

Removal of Arsenic, Tin, and Antimony

5.1.3.

Removal of Noble Metals

5.1.4.

Dezincing

5.1.5.

Debismuthizing

5.1.6.

Final Refining and Casting of Lead

5.1.7.

Processing of Intermediate Products of Pyrometallurgical Refining

5.2.

Electrolytic Refining of Lead Bullion

6.

Recovery of Secondary Lead from Scrap Materials

6.1.

Battery Types and Composition

6.2.

Battery Breaking and Processing Feed Preparation

6.3.

Smelting of Battery Scrap Materials

6.4.

Future Trends

7.

Uses of Lead

8.

Economic Aspects

8.1.

Lead Concentrate Schedules

8.2.

Lead Statistics

9.

Toxicology and Occupational Health

9.1.

Sources of Lead Exposure

9.1.1.

Drinking Water

9.1.2.

Atmosphere

9.1.3.

Soil

9.1.4.

Diet

9.1.5.

Occupational Exposure

9.2.

Absorption and Excretion

9.3.

Effects

9.3.1.

Acute Effects

9.3.2.

Hematologic Effects

9.3.3.

Neurological Effects

9.3.4.

Renal Effects

9.3.5.

Reproduction Effects

9.3.6.

Carcinogenicity

9.4.

Indices for Monitoring Lead Exposure

9.4.1.

Lead in Blood

9.4.2.

Teeth and Hair

10.

Control of Lead Emissions

10.1.

In‐Plant Lead Emissions

10.2.

Ambient Lead Emissions
Social class and adult education
Authors: Nesbit Tom
Published: May 2005

The author introduces the importance of class, providing a historical overview of the concept and discussing its applicability to the study of adult education.
Class in the classroom
Authors: Malcolm Janice
Published: May 2005

This chapter considers how class helps to construct the identity and ultimately the teaching of certain groups of educators, and it explores ways of making class explicit in the teacher education classroom.
Social movements, class, and adult education
Authors: Walters Shirley
Published: May 2005

Social movements in South Africa, often organized around class‐related issues, provide rich material to illustrate how class, intertwined with other social categories, shapes organizational and educational practices.
Class and gender
Authors: Hart Mechthild
Published: May 2005

Everyone is dependent on caring labor. Because women's labor is financially beneficial to global capitalism, gender is inseparable from class, regardless of the specific national or cultural contexts.
Sequential experimental design strategy for rapid kinetic modeling of chemical synthesis
Authors: Issanchou Sébastien , Cognet Patrick , Cabassud Michel
Published: May 2005

In this work, an optimum experimental design strategy has been developed to increase the reliability of chemical reaction engineering models when few experiments are to be performed. The strategy has been used for heterogeneous liquid–liquid reactions carried out in a batch reactor. The specific case of alkaline hydrolysis of n‐amylacetate has been selected to illustrate the proposed methodology, allowing experiments to be carried out to identify the associated kinetic parameters. The kinetic parameters that arise from the model system of ordinary differential equations have been estimated by weighted least squares and a D‐optimum sequential design has been implemented to reduce the volume of the joint confidence region of the parameters. Estimates and their uncertainty obtained at the end of the strategy, as well as the generalization ability of the prediction model, are presented and discussed. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Synthesis and In Vitro Antioxidant Activity of some New Fused Pyridine Analogs
Authors: Al‐Omar Mohamed A. , Youssef Khairia M. , El‐Sherbeny Magda A. , Awadalla Sit. Albanat A. , El‐Subbagh Hussein I.
Published: May 2005

A new series of pyrano[3,2‐c]pyridines, pyrazolo[4,3‐c]pyridines, and pyrido[4,3‐d]pyrimidines were synthesized and screened for their in vitro antioxidant activity. Compounds 13, 14, 15, 23, 29, 30, and 31 exhibited the most active oxygen free‐radical scavenger activity with percentage inhibitions of 99.4, 99.6, 99.8, 97.3, 99.0, 99.3, and 99.5 %; respectively, which is comparable to the curcumin potency. Most of the tested compounds proved to be safe towards peripheral multinuclear neutrophils (PMNs). The detailed synthesis and antioxidant activity data are reported.
Three‐year follow‐up after intravascular γ‐radiation for in‐stent restenosis in saphenous vein grafts
Authors: Rha Seung‐Woon , Kuchulakanti Pramod , Ajani Andrew E. , Cheneau Edouard , Pinnow Ellen E. , Canos Daniel A. , Torguson Rebecca , Pichard Augusto D. , Satler Lowell F. , Kent Kenneth M. , Ramee Steven , Teirstein Paul , Lindsay Joseph , Waksman Ron
Published: May 2005

The Washington Radiation for In‐Stent Restenosis Trial in Saphenous Vein Grafts (SVG WRIST) demonstrated safety and efficacy of intravascular radiation therapy (IRT) for the treatment of in‐stent restenosis (ISR) in SVG at 12 months. In this study, we aimed to examine whether the safety and efficacy of IRT is durable up to 36 months. One hundred twenty patients with diffuse ISR in SVG underwent balloon angioplasty, laser or atherectomy ablation, and/or additional stenting. After successful intervention, patients were randomly assigned in a double‐blind fashion to intravascular treatment with a ribbon containing either iridium (Ir)‐192 (n = 60) or nonradioactive seeds (n = 60). The prescribed dose at 2 mm from the source was either 14 or 15 Gy in vessels 2.5–4.0 mm or 18 Gy in vessels > 4.0 mm in diameter. At 36 months, target lesion revascularization (TLR; 43% vs. 66%; P = 0.02) and target lesion revascularization‐major adverse cardiac event (TLR‐MACE; 49% vs. 71%; P = 0.02) rates continued to be lower in the IRT group, but both target vessel revascularization (TVR; 59% vs. 71%; P = 0.17) and TVR‐MACE (63% vs. 77%; P = 0.11) rates were not. In SVG WRIST, patients with ISR treated with IRT had a marked reduction in the need for repeat TLR at 36 months, with sustained clinical benefit at 3 years despite late recurrences, which were more pronounced in the radiation group. © 2005 Wiley‐Liss, Inc.
Utility of the Ammonia‐Free Birch Reduction of Electron‐Deficient Pyrroles: Total Synthesis of the 20S Proteasome Inhibitor, clasto‐Lactacystin β‐Lactone
Authors: Donohoe Timothy J. , Sintim Herman O. , Sisangia Leena , Ace Karl W. , Guyo Paul M. , Cowley Andrew , Harling John D.
Published: May 2005

A new synthesis of the 20S proteasome inhibitor clasto‐lactacystin β‐lactone is described. Our route to this important natural product involves the partial reduction of an electron deficient pyrrole as a key step. By judicious choice of enolate counterion, we were able to exert complete control over the stereoselectivity of the reduction/aldol reaction. Early attempts to complete the synthesis by using a C‐4 methyl substituted pyrrole are described in full, together with our attempts to promote regioselective elimination of a tertiary alcohol. The lessons learnt from this first approach led us to develop another, and ultimately successful, route that introduced the C‐4 methyl group at a late stage in the synthesis. Our successful route is then described and this contains several highly stereoselective steps including a cis‐dihydroxylation and an enolate methylation. The final synthesis proceeds in just 13 steps and in 15 % overall yield making it an extremely efficient route to this valuable compound.
Absolute Configuration of C2‐Symmetric Spiroselenurane: 3,3,3′,3′‐Tetramethyl‐1,1′‐spirobi[3 H,2,1]Benzoxaselenole
Authors: Petrovic Ana G. , Polavarapu Prasad L. , Drabowicz Jozef , Zhang Yingru , McConnell Oliver J. , Duddeck Helmut
Published: May 2005

The enantiomers of 3,3,3′,3′‐tetramethyl‐1,1′‐spirobi[3 H,2,1]benzoxaselenole have been separated on a chiral preparative chromatographic column. The experimental vibrational circular dichroism (VCD) spectra have been obtained for both enantiomers in CH2Cl2. The theoretical VCD spectra have been obtained by means of density functional theoretical calculations with the B3 LYP density functional. From a comparison of experimental and theoretical VCD spectra, the absolute configuration of an enantiomer with positive specific rotation in CH2Cl2 at 589 nm is determined to be R. This conclusion has been verified by comparing results of experimental optical rotatory dispersion (ORD) and electronic circular dichroism (ECD) to predictions of the same properties using the B3 LYP functional for the title compound.
Coxsackievirus and adenovirus receptor is essential for cardiomyocyte development
Authors: Asher Damon R. , Cerny Anna M. , Weiler Sarah R. , Horner James W. , Keeler Marilyn L. , Neptune Mychell A. , Jones Stephen N. , Bronson Roderick T. , DePinho Ronald A. , Finberg Robert W.
Published: May 2005

The coxsackievirus and adenovirus receptor (CAR) is a transmembrane protein that is known to be a site of viral attachment and entry, but its physiologic functions are undefined. CAR expression is maximal in neonates and wanes rapidly after birth in organs such as heart, muscle, and brain, suggesting that CAR plays a role in the development of these tissues. Here, we show that CAR deficiency resulted in an embryonic lethal condition associated with cardiac defects. Specifically, commencing ∼10.5 days postconception (dpc), CAR−/− cardiomyocytes exhibited regional apoptosis evidenced by both histopathologic features of cell death and positive staining for the apoptotic marker cleaved caspase 3. CAR−/− fetuses invariably suffered from degeneration of the myocardial wall and thoracic hemorrhaging, leading to death by 11.5 dpc. These findings are consistent with the view that CAR provides positive survival signals to cardiomyocytes that are essential for normal heart development. genesis 42:77–85, 2005. © 2005 Wiley‐Liss, Inc.
Utilisation of scattered light for excimer laser beam monitoring
Authors: Hermann A , Kaemling A , Ach F , Fischer C , Viöl W
Published: May 2005

The investigated new online beam monitoring system is
based on the detection of scattered light emitted from a
deflecting mirror in a UV laser beam guidance system. The
scattered light from the mirror is projected on a detector and the
captured data is evaluated by a software. The deflecting
dielectric mirrors used as scattered light source were analysed
with noncontact AFM measurements to predict the expected scattered
light intensity. To test the quality of the measurement technique,
the profiles detected by scattered light were compared with
directly captured profiles. The investigated laser systems emit
wavelengths in the VUV/DUV domain: the fluorine laser at
λ=157 nm, the argon fluoride laser at λ=193 nm,
and the krypton fluoride laser at λ=248 nm. One of the big
advantages of this beam monitoring system is that the laser beam
remains unaffected by the measurement. The system is also capable
of localising the beam and detecting power fluctuations in real
time with high temporal and spacial resolution. An online
measurement during a machining process is therefore possible.
Study of experimental and numerical simulation of laser ablation in
stainless steel
Authors: Khalil A A I , Sreenivasan N
Published: May 2005

In this paper, we present an experimental and
theoretical study of pulse laser ablation of stainless steel
target. Various parameters, such as laser power, pulse duration,
enthalpy and heat capacity are used. The evaluation of which
software will be suitable for the ablation processes has been
done. The possibility to find micro-craters and microdefects was
noted by using Reflection Optical Microscope (ROM). The ablation
process induced by lasers is a collective phenomenon: that
basically involves two phenomena: the laser radiation-with matter
interaction and the dynamic of the ablation plume. A numerical
solution is derived and stimulated for 2-D laser ablation process.
Only the solid – liquid phase change is considered. This study
contributes to a better understanding of the physical processes
involved in the laser ablation targets.
Temperature-tuning Yb:YAG microchip lasers
Authors: Dong Jun , Ueda Ken-ichi
Published: May 2005

Based on the quasi-three-level system, a theoretical
model of diode-laser end-pumped fundamental continuous-wave (CW)
Yb3+:YAG microchip lasers is proposed. The fluorescence
concentration quenching effect, the temperature dependent
mechanical and optical properties and the absorption efficiency of
the host have been taken into account in the model. The
theoretical results of the numerical calculations are in good
agreement with those of experiments. The effects of the
concentration of the Yb3+:YAG crystal, the thickness of the
Yb3+:YAG crystal, the temperature and the transmission of the
output coupler on the laser performance (threshold and output
power) are addressed. The optimization of the concentration and
the thickness for the Yb3+:YAG crystal microchip laser is
presented. The effects of the temperature and the pump power
intensity on the optical-to-optical efficiency are discussed. The
output power can be scaled by increase the working area of the
laser gain medium. This modeling is not only applicable to
Yb3+:YAG crystal microchip laser but also to other
quasi-three-level microchip lasers.
Effect of Free Trimethylaluminum Content in Methylaluminoxane on Performances of Bis(salicylaldiminate)nickel(II)‐Based Catalysts for Ethylene Polymerization
Authors: Carlini Carlo , De Luise Valentina , Grillo Fernandes Elizabeth , Martinelli Marco , Raspolli Galletti Anna Maria , Sbrana Glauco
Published: May 2005

Summary: The performances of ethylene polymerization catalysts based on III and commercial methylaluminoxane were investigated by reducing the content of free trimethylaluminum in methylaluminoxane by its reaction with 2,6‐di‐tert‐butylphenol. This allowed optimization of the formulation of the catalyst, affording a high‐molecular‐weight linear polyethylene (PE) with a productivity [(1 900 kg of PE/(mol of Ni × h)], ten‐fold higher than that previously achieved for the same system adopting commercial methylaluminoxane not pre‐treated with the above phenol derivative.

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Aqueous RAFT Polymerization of Acrylamide and N,N‐Dimethylacrylamide at Room Temperature
Authors: Convertine Anthony J. , Lokitz Brad S. , Lowe Andrew B. , Scales Charles W. , Myrick Leslie J. , McCormick Charles L.
Published: May 2005

Summary: The first example of a room temperature reversible addition‐fragmentation chain transfer polymerization conducted directly in aqueous media is detailed. Under these conditions acrylamide and N,N‐dimethylacrylamide may be polymerized in a controlled fashion to near quantitative conversions employing a difunctional trithiocarbonate chain transfer agent (CTA). Hydrolysis studies conducted at pH 5.5 suggest that the CTA is stable up to approximately 50 °C.

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Gel‐to‐Sol and Sol‐to‐Gel Transitions Utilizing the Interaction of α‐Cyclodextrin with Dodecyl Side Chains Attached to a Poly(acrylic acid) Backbone
Authors: Tomatsu Itsuro , Hashidzume Akihito , Harada Akira
Published: May 2005

Summary: By utilizing the interaction of α‐cyclodextrin (α‐CD) with dodecyl side chains in polymers of x mol‐% dodecyl‐modified poly(acrylic acid) (p(AA/C12(x))), systems that undergo gel‐to‐sol and sol‐to‐gel transitions were successfully constructed. Rheological experiments indicated that addition of α‐CD to the hydrogel of p(AA/C12(5)) caused a drastic decrease in the viscosity, while addition of oligo(α‐CD) to the solution of p(AA/C12(2)) led to a remarkable increase in the viscosity.

Photographs for a gel‐to‐sol transition upon addition of α‐CD to 5.0 g · L−1 p(AA/C12(5)).

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Photographs for a gel‐to‐sol transition upon addition of α‐CD to 5.0 g · L−1 p(AA/C12(5)).
Synthesis and Characterization of Thermally Curable Benzoxazine‐Functionalized Polystyrene Macromonomers
Authors: Kiskan Baris , Colak Demet , Muftuoglu Ali Ekrem , Cianga Ioan , Yagci Yusuf
Published: May 2005

Summary: Thermally curable benzoxazine ring‐containing polystyrene macromonomers were synthesized and characterized. 1,4‐Dibromo‐2,5‐bis(bromomethyl)benzene and 1,4‐dibromo‐2‐(bromomethyl)benzene were used as initiators in the atom transfer radical polymerization of styrene. The resulting polymers were used in combination with 3‐aminophenylboronic acid hemisulfate, for a Suzuki coupling. The obtained polymers, with amino groups in the middle or end of the chains, were reacted with formaldehyde and phenol to yield benzoxazine ring‐containing macromonomers. In addition to the glass transition temperature of the polystyrene segment observed at ca. 105 °C, differential scanning calorimetry thermograms exhibit an exotherm at ca. 276 °C corresponding to the oxazine thermal polymerization. Both macromonomers undergo thermal curing with the formation of thermosets having polystyrene segments.

Structure of the benzoxazine‐functionalized polystyrene.

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Structure of the benzoxazine‐functionalized polystyrene.
Osteopontin induces multiple changes in gene expression that reflect the six “hallmarks of cancer” in a model of breast cancer progression
Authors: Cook Amy C. , Tuck Alan B. , McCarthy Susan , Turner Joel G. , Irby Rosalyn B. , Bloom Gregory C. , Yeatman Timothy J. , Chambers Ann F.
Published: May 2005

Tumor progression is a multistep process, which enables cells to evolve from benign to malignant tumors. This progression has been suggested to depend on six essential characteristics identified as the “hallmarks of cancer,” which include: self‐sufficiency in growth signals, insensitivity to growth‐inhibitory signals, evasion of apoptosis, limitless replicative potential, sustained angiogenesis, and tissue invasion and metastasis. Osteopontin (OPN) is an integrin‐binding protein that has been shown to be associated with the progression of several cancer types, and to play an important functional role in various aspects of malignancy, particularly tissue invasion and metastasis. Here we studied genes regulated by OPN in a model of human breast cancer using oligonucleotide microarray technology by comparing the gene‐expression profiles of 21NT mammary carcinoma cells transfected to overexpress OPN versus mock‐transfected control cells. From over 12,000 human genes, we identified 99 known human genes differentially regulated by OPN whose expression changed by at least 1.5‐fold and showed statistically significant differences in mean expression levels between groups. Functional classification of these genes into the hallmarks of cancer categories showed that OPN can affect the expression of genes involved in all six categories in this model. Furthermore, we were able to validate the expression of 18/19 selected candidate genes by quantitative real‐time PCR, further supporting our microarray findings. This study provides the first evidence that OPN can lead to numerous gene expression changes that influence multiple aspects of tumor progression and malignant growth. © 2005 Wiley‐Liss, Inc.
The effect of PPARγ ligands on UV‐ or chemically‐induced carcinogenesis in mouse skin
Authors: He Guobin , Muga Stephanie , Thuillier Philippe , Lubet Ronald A. , Fischer Susan M.
Published: May 2005

Peroxisome proliferator‐activated receptor γ (PPARγ) is a ligand activated transcription factor. There have been suggestions that PPARγ ligands may have utility in preventing tumor development in rodent mammary glands and colon. The recent finding that mice lacking one allele of the PPARγ gene were significantly more susceptible to 7,12‐dimethylbenz[a]anthracene (DMBA)‐induced skin carcinogenesis compared to wild‐type mice highlights mouse skin as another potential organ in which PPARγ ligands may be effective as chemopreventive agents. In this study, we assessed the effect of two PPARγ ligands (rosiglitazone and troglitazone) on UV and DMBA/12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐induced mouse skin carcinogenesis, two of the most commonly used mouse skin carcinogenesis models. Unexpectedly, neither rosiglitazone (dietary 200 ppm) nor troglitazone (topical 100 μg) significantly inhibited UV‐induced skin tumor development in SKH‐1 hairless mice. Likewise, dietary rosiglitazone did not statistically significantly inhibit DMBA/TPA‐induced skin tumor development. Interestingly, dietary troglitazone significantly inhibited basal level keratinocyte proliferation as shown by 5‐bromo‐2′‐deoxyuridine (BrdU) labeling, but it had no effect on TPA‐induced epidermal cell proliferation. Northern blot analysis showed that PPARγ expression was extremely low in normal mouse epidermis and was virtually undetectable in skin tumors. Collectively, our data suggest that PPARγ ligands may not be useful in the prevention of chemically or UV‐induced skin tumors. © 2005 Wiley‐Liss, Inc.
Association of non‐starch polysaccharides and ferulic acid in grain amaranth (Amaranthus caudatus L.) dietary fiber
Authors: Bunzel Mirko , Ralph John , Steinhart Hans
Published: May 2005

The association of ferulic acid, an alkali‐extractable phenolic acid in amaranth (Amaranthus caudatus L., Amaranthaceae) insoluble fiber (trans‐ferulic acid: 620 μg·g–1, cis‐ferulic acid: 203 μg·g–1), and non‐starch polysaccharides was investigated. Enzymatic hydrolysis of insoluble amaranth fiber released several feruloylated oligosaccharides that were separated using Sephadex LH‐20‐chromatography and reversed phase‐high performance liquid chromatography (RP‐HPLC). Three compounds were unambiguously identified: O‐(6‐O‐trans‐feruloyl‐β‐D‐galactopyranosyl)‐(1→4)‐D‐galactopyranose, O‐(2‐O‐trans‐feruloyl‐α‐L‐arabinofuranosyl)‐(1→5)‐L‐arabinofuranose, and O‐α‐L‐arabinofuranosyl‐(1→3)‐O‐(2‐O‐trans‐feruloyl‐α‐L‐arabinofuranosyl)‐(1→5)‐L‐arabinofuranose. These feruloylated oligosaccharides show that ferulic acid is predominantly bound to pectic arabinans and galactans in amaranth insoluble fiber. 5‐O‐trans‐Feruloyl‐L‐arabinofuranose was the only compound isolated in pure form from an acid hydrolyzate. This compound may have its origin from pectic arabinans but also from arabinoxylans.
Evidence for the γ‐relaxation in the light scattering spectra of poly (n‐hexyl methacrylate) near the glass transition
Authors: Savin Daniel A. , Patterson Gary D. , Stevens James R.
Published: May 2005

The full range of relaxation processes present in optically pure poly‐(n‐hexyl methacrylate) (PHMA) was studied using Rayleigh–Brillouin and photon correlation spectroscopy (PCS). Brillouin shifts, linewidths, and Landau–Placzek ratios (LPR) were measured over the temperature range from −11 to 21 °C. The Brillouin splitting and linewidth were consistent with previous studies of PHMA, but the LPR was much lower, indicating that the scattered light primarily comes from intrinsic density fluctuations. Relaxation functions of the same PHMA sample were measured using PCS over the temperature range 0.5–52.5 °C. The average relaxation times calculated from a Williams–Watts fit follow a VFT temperature dependence, with the stretching parameter β decreasing with decreasing temperature. The distribution of relaxation times reveals a merging of the α and β‐relaxations over this temperature range, and the temperature dependent width confirms that there are at least two processes with separate temperature dependences. Furthermore, there appears a process at short times in the correlation function window at low temperatures. This upturn at the fastest relaxation times is attributed to the γ‐relaxation present in higher order methacrylate polymers. The effect of the γ‐relaxation is discussed in terms of the dynamic behavior over 12 decades in time. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1504–1519, 2005
Deformation and molecular orientation in films of metallocene polypropylene, ethylene–butylene rubber, and their 80/20 (w/w) blend revealed by the simultaneous kinetic measurement of microscopic infrared dichroism, macroscopic stress, and mesoscale strain
Authors: Naka Yoshihito , Nemoto Norio , Song Yihu
Published: May 2005

Simultaneous kinetic measurement of microscopic infrared dichroism, macroscopic stress, and mesoscale strain was used to study the deformation mechanisms of metallocene polypropylene (MPP), ethylene–butylene rubber (EBR), and their blend (MPP/EBR = 80/20 w/w). As with pure MPP, the molecular orientation in the blend is dominated by the necking of the isotactic polypropylene matrix. During the necking passage through the mesoscale sampling area, the molecular orientation of the polypropylene matrix in the blend is smaller than that in the pure polypropylene film at the same level of mesoscale strain. However, the orientation of the EBR dispersed phase in the blend is larger than that in the pure EBR film. This may result from the partial miscibility of the two ingredients in the amorphous phases and their resultant strong interfacial interaction. The large stress supported by the MPP matrix extends to the island of the EBR domain and leads to its large deformation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1520–1531, 2005
On double barrier quantum well conductance effects due to exchange and correlation
Authors: Hasbun J. E.
Published: May 2005

Conductance investigations in double barrier resonant tunneling (DBRT) structures under an applied voltage usually make use of the BenDaniel–Duke equation (BDK), coupled to the Poisson equation, to incorporate electron interactions through the Hartree term in a self‐consistent way. By including an extra self‐consistency condition, it is possible to go beyond the Hartree approximation and include exchange and correlation (EC) effects through the local density approximation (LDA). In this paper, the inclusion of EC effects is made by means of the analytically parametrized υinf
xc of Hedin and Lundqvist. A comparison with previous work that excludes such effects is carried out for the energy spectrum as well as for the field dependent conductance in a GaAs/AlGaAs DBRT structure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Peculiarities of resonances of elastic and magnetoelastic waves in (111)‐oriented two‐layered structure
Authors: Gareyeva Z. V. , Doroshenko R. A. , Vakhitov R. M. , Ryakhova O. G.
Published: May 2005

The dimensional resonant frequency of elastic and magnetoelastic waves in bilayered structure: magnetic film‐non‐magnetic elastic substrate have been explored. The diagrams of resonant frequencies dependences upon material parameters of a system such as wave resistances, layers thicknesses have been constructed. Violation of the equidistant arrangement of resonant frequency harmonics for a composite bilayered structure has been shown. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)