bluuebunny/crossref_metadata_2025 huggingface dataset:
Average Age at Death
Authors: Kravitz Howard M.
Published: July 2005

This article describes the fallacy of “average age at death”, a common misuse of age data for summarizing mortality experience and estimating life expectancy. An example is presented to illustrate this fallacy. Considerations that should be taken into account for more accurate analysis of these data are reviewed.
Double Sampling
Authors: Rao Poduri S. R. S.
Published: July 2005

Double sampling is of practical importance for the estimation of population characteristics from sample surveys and for other purposes. This approach for the estimation of stratum weights and the mean of the auxiliary variable for ratio and regression estimators is presented. Its applications for the ratio estimation with subsampling the nonrespondents in a survey, for determining sample sizes in analytical surveys, and for multistage and successive sampling are also described.
Establishment Surveys With Population Survey–Generated Sampling Frames
Authors: Sirken Monroe , Shimizu Iris
Published: July 2005

When stand‐alone sampling frames list all establishments and size measures, the Hansen–Hurwitz (HH) pps estimator is generally used to estimate the volume of transactions between establishments and households. The network sampling (NS) version of the HH estimator depends on a population‐survey‐generated establishment frame, which lists establishments that have transactions with households in a population sample survey and the number of transactions that establishments have with survey households. The NS estimator is a competitor of the HH estimator whenever stand‐alone frames of good quality are unavailable and, as this article indicates, the NS estimator may be competitive with the HH estimator when stand‐alone and population‐survey‐generated frames are flawless.
Interpenetrating Samples
Authors: Ghosh Subir
Published: July 2005

This article presents an overview of interpenetrating sampling (IPS), also known as interpenetrating subsampling and replicated sampling. IPS was introduced in the pioneering contribution of P.C. Mahalanobis. It was originally proposed in assessing the nonsampling errors as the so‐called “interviewer errors”. IPS provides a quick, simple, and effective way of estimating the variance of an estimator even in a complex survey. In fact, IPS is the foundation of modern resampling methods like Jackknife, bootstrap, and replication methods. In IPS, three basic principles of experimental designs, namely, randomization, replication, and local control, are used. IPS is used extensively not only in agriculture, but also in social sciences, demography, epidemiology, public health, and many other fields.
Sampling With and Without Replacement
Authors: Hsia Jason
Published: July 2005

Sampling with replacement is a class of sampling procedures in which the selected elements are replaced in the selection pool following each “draw” and may be reselected on subsequent draws. In contrast, sampling without replacement is a class of procedures in which the already selected elements are not replaced in the pool and cannot be selected again.
Superpopulation Models in Survey Sampling
Authors: Dorfman Alan H. , Valliant Richard
Published: July 2005

In sampling from a finite population, we often find it reasonable to posit a probability model (“superpopulation model”) that characterizes relations among variables that pertain to the units of the population. Such a model enables us to make inferences about population characteristics based on sample measurements and “auxiliary information”. In effect, we use the model to predict values for those units of the population that have not been sampled. In such prediction‐based (or model‐based) sampling and inference, it is important to guard against problems arising from model failure. Selecting a balanced sample or weighted balanced sample provides bias protection in the important case of estimating means or totals. Robust variance estimators guard against misapprehension of the variance structure.
Youden Squares and Row–Column Designs
Authors: Gupta Sudhir
Published: July 2005

Often several other factors potentially contribute to the variability of the observed response in addition to the treatments or factors under investigation. For example, gender, age, and center may also affect the blood pressure of patients in a placebo‐controlled hypertensive clinical trial. The technique of blocking is used to control the experimental error variation due to these types of extraneous sources. Two sources can be controlled using a Youden square or a row–column design, the rows and columns comprising two different systems of blocking. This article provides the details for the least squares analysis of these designs. Designs having variance balance, supplemented balance, row‐orthogonality, adjusted‐orthogonality, designs for factorial experiments, and computer algorithms for constructing designs are also briefly discussed.
B
liss,
C
hester
I
ttner
Authors: Holford Theodore R. , White C.
Published: July 2005

Born in 1899 in Springfield, OH; died in 1979. Bliss is best known for work on probit (probability integral transformation) analysis, much of it in collaboration with R.A. Fisher, and also for playing a major role in founding the International Biometric Society.
B
yar,
D
avid
P
.
Authors: Piantadosi Steven
Published: July 2005

Born in 1938 in Lockland, OH; died in 1991 in Washington D.C. Byar was a leading clinical trials methodologist and proponent of structured experiments for making treatment inferences. He played an important role in teaching and advocating the strengths of clinical trials through his positions at the National Cancer Institute. He also made substantial contributions to epidemiology and studies of disease prevention.
Centers for Disease Control and Prevention (CDC)
Authors: Reynolds Gladys H.
Published: July 2005

The Centers for Disease Control & Prevention (CDC) evolved from a small mosquito‐eradication effort in World War II to being the USA's primary agency in the promotion of health and the prevention of disease. Initial efforts focused on prevention and control of unnecessary morbidity and mortality from infectious diseases of public health importance, such as malaria, polio, smallpox, toxic shock syndrome, Legionnaires' disease, and more recently, AIDS, Ebola virus, Hantavirus, monkeypox, and SARS. These responsibilities have expanded to include contemporary threats to health, such as lead‐paint poisoning, environmental, and occupational hazards. The National Center for Health Statistics (NCHS) became a part of the CDC in 1987.
C
ochran,
W
illiam
G
emmell
Authors: Dempster A.P.
Published: July 2005

Born 1909, Rutherglen, Scotland; died 1980 Orleans, MA. Leading contributor to the British–American school of applied statistics during a period of rapid development of the field across the middle decades of the twentieth century.
de
F
inetti,
B
runo
Authors: Lindley Dennis V.
Published: July 2005

Bruno de Finetti (1906–1985) is appreciated today for his view of probability as a measure of your belief in the truth of a proposition, the requirement that your beliefs be coherent, expressed through the laws of probability, and the connection between beliefs and frequency by means of his notion of exchangeability.
E
uropean Federation of Statisticians in the Pharmaceutical Industry (
EFPSI
)
Authors: Godley Mick , Jørgensen Merete
Published: July 2005

The Federation is open to nationally constituted groups of statisticians who are working in or for the pharmaceutical industry. The Federation was constituted in 1992, and in 2004, includes eleven member groups. EFSPI is engaged in statistical aspects of research, development, production, and postmarketing surveillance of drugs, biologics, and medical devices.
G
avarret,
L
ouis–
D
enis–
J
ules
Authors: Matthews J. Rosser
Published: July 2005

Gavarret (1809–1890) was medically qualified. In 1840, he published an influential book on medical statistics drawing on the probabilistic results of S.D. Poisson concerning the sampling error of a proportion.
G
uy,
W
illiam
A
ugustus
Authors: Armitage Peter
Published: July 2005

Guy wrote on medical statistics in the mid‐nineteenth century and helped to popularize the work of P. C. A. Louis. He is commemorated in the Guy Medal of the Royal Statistical Society.
H
alley,
E
dmond
Authors: Asmar Lina
Published: July 2005

Edmond Halley was born on November 8, 1656 in Haggerton, UK. He was a major English, astronomer, mathematician, and physicist, who was also interested in demography, insurance mathematics (Actuarial Methods), geology, oceanography, geography, and navigation. Moreover, he was considered an engineer and a social statistician whose life was filled with the thrill of discovery. In 1705, he reasoned that the periodic comet—now known as Halley's comet—that appeared in 1456, 1531, 1607, and 1682, was the same comet that appears every 76 years, and accurately predicted that it would appear again in December 1758. His most notable achievements were his discoveries of the motion of stars, which were then considered fixed, and a scheme for computing the motion of comets and establishing their periodicity in elliptical orbits. Edmond Halley died on January 14, 1742 in Greenwich, UK.
H
ill,
A
ustin
B
radford
Authors: Doll R.
Published: July 2005

Born 1897; died 1991. A. Bradford Hill introduced the principle of randomization in clinical trials. He was influential in establishing the link between smoking and lung cancer, and as a result of this research drew up guidelines for reaching a positive conclusion about causality. These criteria have come to be widely used in epidemiology and, on occasion, the law.
Biostatistics, History of
Authors: Matthews J. Rosser
Published: July 2005

Methodologic developments since the seventeenth century work of Graunt are considered in four phases: nineteenth century developments in social and medical statistics; the work of Karl Pearson and the biometric school; Fisher's methods of hypothesis testing; and the postwar rise of epidemiologic studies.
I
rwin,
J
oseph
O
scar
Authors: Armitage Peter
Published: July 2005

After periods of work under Karl Pearson and R. A. Fisher, Oscar Irwin joined the staff of the Medical Research Council in 1931 and thereafter became the leading mathematical statistician in British medical research. He had a wide range of theoretical interests, including the use of the characteristic function, the development of the exact test for the 2 × 2 table, and the Waring distributions. His biometric interests included bioassay, factor analysis, accident proneness, and carcinogenicity experiments.
L
ancaster,
H
enry
O
liver
Authors: Armitage Peter
Published: July 2005

Oliver Lancaster (1913–2001) was a distinguished Australian medical statistician. He was unique in having held university chairs in both medical and mathematical statistics, in making important contributions to the history of quantitative medicine, and in his pioneering work in the bibliography of statistics.
Leukemia Clusters
Authors: Bithell John F.
Published: July 2005

Clusters of cases of childhood leukaemia have been reported near nuclear installations. They are difficult to explain in terms of the level of environmental radiation, and viral etiologies have been suggested. The selective nature of the data makes rigorous analysis difficult. Evidence for a general tendency of leukaemia to cluster is equivocal.
Martini, Paul
Authors: Dengler H. J.
Published: July 2005

Paul Martini (1889–1964) was a distinguished professor of internal medicine, working in Munich, Berlin and (from 1932) in Bonn. His 1932 book on therapeutic research was influential in encouraging the application of statistical methods. Later, he expressed reservations about double‐blind (as distinct from single‐blind) trials.
M
edicines and
H
ealthcare
P
roducts
R
egulatory
A
gency (
MHRA
) (Formerly
MCA
)
Authors: Evans Stephen J. W. , Day Simon J.
Published: July 2005

In April 2003, the UK Medicines Control Agency and Medical Devices Agency merged to form the Medicines and Healthcare products Regulatory Agency (MHRA). Most of the statistical work is confined to the Medicines Sector of this new Agency. Statisticians are involved in assessing clinical trial documentation submitted by pharmaceutical companies as applications for marketing authorizations. They are also involved in pharmacovigilance monitoring of currently marketed products.
Neyman,Jerzy
Authors: Chiang Chin Long
Published: July 2005

Jerzy Neyman, one of the principal architects of modern statistics, was Director of the Statistical Laboratory, University of California, Berkeley. He was born on April 16, 1894, into a Polish family in Bendery, Russia, and died on August 5, 1981, in Berkeley, California, at the age of 87. With Neyman's passing, history closed a chapter on the early development of this important scientific field.
Pharmaceutical Industry, Statistics In
Authors: Senn Stephen
Published: July 2005

The role of the statistician is traced from early, basic research through the various stages of drug development leading to phase III clinical trials and phase IV postmarketing surveillance. Specific areas of activity, and statistical topics of particular interest, are listed. Examples are taken from the development of drug for treating asthma, and work on project prioritization. Future trends will be affected by financial constraints, by a need to specialize that may lead to work being done by contract research organizations, by the need for speed, and by the need for marketing to be more “evidence‐based”.
R
asch,
G
eorg
Authors: Andersen Erling B.
Published: July 2005

Georg Rasch (1901–1980) worked at the State Serum Institute and the University of Copenhagen, where he was Professor of Statistics from 1962 to 1972. He worked in various fields of mathematics and applied statistics, especially in intelligence testing. He developed factor analysis and introduced latent trait models.
R
emington,
R
ichard
D
Authors: Woolson R. F.
Published: July 2005

Richard Remington (1931–1992) was a leading public health statistician who played a major role in linking biostatistics and epidemiology to public health research and policy. He held senior appointments at the Universities of Michigan, Texas, and Iowa. At Iowa, he served as Interim President of the University in 1987–1988 and founded the Institute for Health, Behavior, and Environmental Policy in 1992. He had a major research interest in the public health impact of hypertension and served on many NIH committees. He coauthored, with M.A. Schork, a popular textbook.
Statistical Review for Medical Journals, Guidelines for Authors
Authors: Rubinstein Lawrence V.
Published: July 2005

Various individuals and groups have suggested guidelines for authors, governing the format and content of statistical reporting in medical articles. The present article presents guidelines for clinical trials, based closely on those of the CONSORT group. The headings are as follows: Introduction; Methods, Protocol Design; Methods, Treatment Assignment; Methods, Treatment Blinding; Methods, Quality Control; Results, Follow‐up Schedule, and Loss to Follow‐up; Results, Analysis; and Comment.
S
tocks,
P
ercy
Authors: Armitage Peter
Published: July 2005

Stocks left an academic post in medical statistics to become the Chief Medical Statistician at the General Register Office in London for 17 years. He played a leading part in revisions of the
International Classification of Diseases
and later worked on studies of cancer epidemiology.
Teaching Statistics to Physicians
Authors: Murray Gordon D.
Published: July 2005

Some familiarity with statistics is important for physicians, for both research and routine practice. Teaching needs are reviewed for three groups: practitioners, casual researchers, and professional researchers. Requirements for undergraduate and postgraduate courses are discussed.
Geisser,Seymour
Authors: Christensen Ronald , Johnson Wesley
Published: July 2005

Seymour Geisser was a leading proponent of the importance of prediction in the practice of statistics, as well as a leading exponent of multivariate analysis. He pioneered several important areas of statistical endeavor, such as the now popular method for validating statistical models called cross‐validation, and the equivalent method of predictive sample reuse. He also pioneered the areas of Bayesian multivariate analysis and discrimination, Bayesian diagnostics for statistical prediction and estimation models, Bayesian interim analysis, and testing for Hardy–Weinberg equilibrium using forensic DNA data.
Health Care Technology Assessment
Authors: Sheldon Trevor A.
Published: July 2005

Health technology assessment is a scientific exercise to provide evidence for health care decision makers who wish to ensure that the introduction of health technologies, such as drugs and devices, is managed in order to control costs and optimize the benefits. Health technology assessment (HTA) is the process of assessing the effectiveness, cost‐effectiveness and, more broadly, the medical, social, ethical, and economic implications of the use of a health technology in practice. Thus, it ranges from the very technical activities of investigating the reliability of a diagnostic test, through the evaluation of the cost‐effectiveness and safety of a drug all the way to policy analysis. The results are used to inform the decisions of health care policymakers, funders and providers of health care, and by the public.
Hollow Microcapillary Arrays in Thin Plastic Films
Authors: Hallmark B. , Mackley M. R. , Gadala‐Maria F.
Published: July 2005

Microcapillary film (MCF) is a new material, produced by a continuous extrusion process, that has hybrid product characteristics linked to polymer foam, polymer film and single hollow‐fibre extrusions. MCFs have unique properties which, combined with their ease of production, may lead to exciting new developments and applications in the physical and engineering sciences, medicine and the life sciences.
Mixing Entropy Difference between Liquid and Crystal of Zr Base Amorphous Alloys
Authors: Chi B. Q. , Jiang Q.
Published: July 2005

A relation between ΔS and n of bulk Zr base metallic glasses (BMGs) is developed, where ΔS denoted the mixing entropy difference between the liquid and the crystal, n is component number. In terms of this relation, n > 4 ‐ 5 does not evidently increases ΔS which is related to the glass forming ability. The results are consistent with the corresponding critical cooling rates coming from the experiments.
Cast NiTi Shape‐Memory Alloys
Authors: Ortega A. M. , Tyber J. , Frick C. P. , Gall K. , Maier H. J.
Published: July 2005

The purpose of this study is to build a fundamental understanding of the relationship between the structure and properties of cast nickel‐titanium (NiTi). The structure of the cast material will be analyzed at various scales and will be related to the properties of the cast material such as transformation temperatures, stress‐strain behavior, and recovery properties. This study demonstrates that cast NiTi can possess excellent shape‐memory properties.
Processing of Net‐shaped Nanocrystalline Fe‐Ni Material
Authors: Lee J.‐S. , Cha B.‐H. , Kang Y.‐S.
Published: July 2005

Development of nanoparticulate materials technology is essential to processing of highly functional nanoparticulate materials and components with small and complex shape. This paper provides an overview on our recent investigations on the processing of net‐shaped nanocrystalline Fe‐Ni powder and related material property such as mechanical property. The key‐processing concept is the synthesis of nanopowders and subsequent consolidation with controlled microstructure by using powder injection molding (PIM) process. Especially, the pressureless sintering process is inevitable for consolidation of the PIMed nanopowder. The present review focuses on the densification process and related mechanical property of the PIMed Fe‐Ni nanopowder in association with microstructural evolution and diffusion process.
TEM Study of Precipitates in Melt‐Spun Mg‐Zn‐Y‐La Alloys
Authors: Rao J. , Kawamura Y. , Inoue K.
Published: July 2005

Recently, nano‐crystalline MgZn1Y2 alloys exhibiting excellent tensile yield strength elongation ratio have been developed as a consequence of preliminary investigations of alloy compositions using melt‐spun ribbons. Their results show that the novel long‐period hexagonal atomic configurations in the Mg‐Ln‐Zn alloys as well as the atomic scale enrichment of Ln and Zn elements into the misfit atomic array sites indicates the possibility that a high‐strength Mg‐based alloy is developed by the control of the novel structure and the atomic scale segregation mode.
Functionalized Cluster‐Assembled Magnetic Nanostructures for Applications to high Integration‐Density Devices
Authors: Perez A. , Dupuis V. , Tuaillon‐Combes J. , Bardotti L. , Prevel B. , Bernstein E. , Mélinon P. , Favre L. , Hannour A. , Jamet M.
Published: July 2005

This paper presents recent results on the preparation and characterization of original magnetic nanostructures from nanoclusters preformed in the gas phase. Magnetic binary‐clusters (i.e. Co‐Sm, Co‐Pt, Co‐Ag) with rather well controlled sizes, structures and compositions, are prepared in the gas phase using a combined laser vaporization‐rare gas condensation source and subsequently deposited at low energy (LECBD : Low Energy Cluster Beam Deposition) on various functionalized substrates to grow cluster‐assembled magnetic nanostructures exhibiting specific magnetic properties. Especially a high magnetic anisotropy and consequently a high magnetic blocking temperature compatible with future applications to high density memory devices and spin electronics are expected. In this context of applications, 2D‐organized arrays of functionalized binary‐cluster assembled dots are prepared by LECBD on FIB‐functionalized substrates (FIB: Focussed Ion Beam) with the ultimate objective to reach areal densities in the range of the Tbits/in2.
Fabrication and Properties of Hybrid SiCp‐Cf/Al Composite for Tribological Applications
Authors: Imielinska K. , Le Petitcorps Y.
Published: July 2005

In the present work fabrication of the new hybrid SiCp/Cf/Al‐Si composite, candidate for tribological applications (e.g. brake discs), has been proposed. The composite was obtained by pressure infiltration of continuous 3D carbon fibre preform with SiCp/Al‐Si particulate composite. The presence of carbon preform acted as a filter for liquid SiCp/Al‐Si composite and permitted the formation of surface layer rich in SiC (up to 50%) which resulted in the reduction of weight loss in dry sliding over steel as well as in minimizing the smearing effect of aluminum on the counterface surface which resulted in the reduction of heating on the sliding surface. Due to the presence of continuous carbon fibres the thermal expansion coefficient of hybrid composite has been reduced by a factor of two as compared with that of SiC/Al‐Si composite.
Preparation of Dense Nanocrystalline Silicon Carbide Ceramics by Sinter Forging in the Presence of a Liquid Phase
Authors: Wetzel K. , Rixecker G. , Kaiser G. , Aldinger F.
Published: July 2005

Dense SiC materials from ultrafine starting powders may be obtained with very limited grain growth if uniaxial hot pressing with concurrent lateral flow of the sample is applied. This process, termed sinter forging, allows to decouple the kinetics of densification and grain growth owing to the elimination of the largest and most persistent population of pores by viscous deformation under the action of shear forces.
Process Chain for Tailoring the Refractive Index of Thermoplastic Optical Materials using Ceramic Nanoparticles
Authors: Ritzhaupt‐Kleissl E. , Böhm J. , Haußelt J. , Hanemann T.
Published: July 2005

Interconnections between active optical devices like laser diodes and polymer optical fibres are a crucial factor of optical damping due to coupling losses at the interfaces. Tailoring the refractive index of thermoplastic polymers can diminish these damping losses. The use of modified thermoplastics in an injection moulding process allows a high throughput and therefore a cost effective method for manufacturing passive optical parts with improved properties.
The Versatile Thiophene: An Overview of Recent Research on Thiophene‐Based Materials
Authors: Barbarella G. , Melucci M. , Sotgiu G.
Published: July 2005

In the last few years, thiophene‐based materials, which are semiconductor and fluorescent compounds, have become a highly interdisciplinary field of research, with diverse studies ranging from the fabrication of electronic and optoelectronic devices to the selective detection of biopolymers. This article presents a survey of the papers published in the last two years and concludes with the authors' views on future developments.
Bulking and Foaming in France: The 1999–2001 Survey
Authors: Graveleau Laure , Cotteux Eric , Duchène Philippe
Published: July 2005

To assess bulking in French wastewater treatment plants we developed a three‐topic approach, including analysis of i) technical assistance annual reports, ii) a questionnaire, and iii) microscopic sample observations. A seasonal effect was very apparent on the average SVI (mL/g). Three situations appear to promote bulking according to statistical analysis and operators' comments: i) low‐organic loading or rapid variation in organic loading, ii) raw sewage dilution or hydraulic loading variation, iii) rapid high‐organic loading. Phosphorus removal by metallic salt addition leads to an average SVI reduction of 40 mL/g.

Two situations in the sludge treatment process, which call for improvement, are:

– The maintaining a high MLSS concentration in the aeration tank due to the limitation of sludge evacuation,

– When storing sludge for several days or weeks in sludge thickening tank, thereby favoring the formation of septic compounds, which are subsequently reintroduced in the influent.

Our study highlights Type 0092 as the most frequent filamentous microorganism observed followed by Microthrix parvicella. Thiothrix spp. ranks third.
Non‐famous Scum Bacteria: Biological Characterization and Troubleshooting
Authors: Lemmer Hilde , Lind George , Müller Elisabeth , Schade Margit
Published: July 2005

Scum biocenoses in activated sludge nutrient removal plants besides “nocardioform actinomycetes” and “Microthrix parvicella” frequently accommodate other conspicuous organisms such as Eikelboom types 0041/0675, 0581, 0092, and 1851, as well as “Nostocoida limicola”‐like organisms. In the scum fraction of high load plants often bacteria of type 1863 and non‐filamentous actinomycetes are found. Many of these morphologically distinguishable scum bacteria are so‐called morphotypes belonging to various groups or genera of bacteria as was proved by fluorescence in situ hybridization (FISH). Aim of this paper is to summarize our respective actual findings and the difficulties to provide practitioners with effective troubleshooting measures for these organisms.
Population Structure and Chemical EPS Analyses of Activated Sludge and Scum
Authors: Müller Elisabeth , Lind George , Lemmer Hilde , Wilderer Peter A.
Published: July 2005

The objective of this study was to quantify scum bacteria by FISH‐technique and to correlate their numbers to the hydrophobicity and EPS compounds extracted from sludge and scum. Screening experiments from various wastewater treatment plants (WWTPs) demonstrated that in most plants examined “Microthrix parvicella” was found in high numbers both in activated sludge and scum. Further nocardioform actinomycetes and type 1863 identified as Acinetobacter spp. could be characterized as important scum bacteria growing in low numbers in activated sludge and being enriched in scum layers. On the basis of these screening results, one nocardioform actinomycetes/Acinetobacter spp.‐dominated WWTP1 and one “M. parvicella”‐dominated WWTP2 were selected for detailed investigations. In actinomycetes/Acinetobacter‐dominated WWTP1 both lipophilic substances in the EPS and hydrophobic cell surfaces stabilized the scum layer. In “M. parvicella”‐ dominated WWTP2 the hydrophobic cell surfaces of these organisms were responsible for the hydrophobic sludge properties and sludge floating. In both of the selected WWTPs the detected lipophilic substances in the EPS improved growth rate and development of hydrophobic cell surfaces and therefore promoted scum processes.
Effect of Coagulant Dosing on Physicochemical and Microbiological Characteristics of Activated Sludge and Foam Formation
Authors: Lánský Milan , Ruz̆ic̆ková Iveta , Benáková Andrea , Wanner Jir̆í
Published: July 2005

The paper examines the effect of coagulant dosing on stable biological foam formation and occurrence of filamentous microorganisms. Physicochemical (surface charge, extracellular polymers concentration and composition) and biological parameters (sedimentation characteristics, microscopical analysis) were determined for this purpose. Coagulant dosing was found to suppress biological foam formation and filamentous microorganisms Microthrix parvicella presence in activated sludge.Close connection between sludge volume index and EPS amount was detected during experiment.
Measurement of Foam Quality of Activated Sludge in MBR Process
Authors: Nakajima Jun , Mishima Iori
Published: July 2005

MBR (membrane bioreactor) process has been applied to wastewater treatment plants recently. It is well known that the most important point of the optimum maintenance is control of membrane clogging in the process. Suitable indices for operation and maintenance in MBR are desired to predict the timely cleaning period and carry out the effective cleaning of the membrane. A large amount of foam is sometimes produced in MBR facilities. Some foam seems to be produced by extracellular protein that is known to cause the membrane clogging. Therefore measurement methodology of foam quality produced by activated sludge in MBR process and characteristics of its extracellular polymer substances (EPS) were studied. The conclusions were: (1) EPS was able to be extracted by steaming treatment on the optimum condition at 105 °C for 30 minutes. (2) Bingham viscosity and yield stress of activated sludge were measured. The yield stress was contributed by EPS and this suggested that EPS was one important factor for foaming. (3) The measurement of foam quality using a video camera showed good performance. The foaming power and the foam stability increased proportionally with the concentration of protein in EPS. It was clear that the protein concentration in EPS was strongly related to the foam quality and quantity. (4) The foaming power decreased by addition of MLSS. This decrease was caused by adsorption of EPS to MLSS. Foaming in an aeration tank will be an index for membrane cleaning requirement.
Lipase Activities in Activated Sludge and Scum – Comparison of New and Conventional Techniques
Authors: Schade Margit , Lemmer Hilde
Published: July 2005

Lipase activities in activated sludge and scum were determined by both conventional in vitro methods and in situ measurements using the ELF (enzyme labeled fluorescence)‐technology where enzyme activity can be observed right at the site of activity. Activities were determined in a two‐stage municipal wastewater treatment plant (WWTP) as well as in three one‐stage WWTP's. In the high load first stage (F:M ratio given as mass of BOD5 related to mass of mixed liquor suspendid solids and day: 0.64 kg kg−1 d−1) of the two‐stage municipal WWTP being dominated by nocardioform actinomycetes lipase activity was somewhat higher in activated sludge as compared to scum. In contrast activities in the low load second stage (F:M ratio 0.02…0.05 kg kg−1 d−1) were significantly higher in the scum fraction. High lipase activities were measured in the one‐stage WWTP 2 being dominated by “Microthrix parvicella”. In situ ELF‐technology assigned the lipase activity to “M. parvicella” filaments with high activity in sludge and reduced activity in scum. In WWTP 3 with alternating dominance of actinomycetes and “M. parvicella” in scum both in vitro and in situ measurements revealed lower activities when actinomycetes were dominating. This suggests their lower degradation activity of long‐chain fatty acids (oleate, palmitate). AlCl3 addition in a pilot scale activated sludge treatment plant led to a significant decrease of lipase activity of the dominating “M. parvicella” filaments which could readily be monitored by both techniques after only two days of dosage.
Foaming Estimation Tests in Activated Sludge Systems
Authors: Torregrossa Michele , Viviani Gaspare , Vinci Valentino
Published: July 2005

Persistent biological foaming phenomena in activated sludge systems due to excess of filamentous microorganisms with hydrophobic properties, such as GALO, Microthrix parvicella and others, are frequently reported everywhere. Nevertheless, even if the number of plants affected by this trouble is high, presently there are no suitable general methods to evaluate properly the phenomenon. This paper reports on the results of a series of foam tests (Scum Index, Foam Rating), of hydrophobicity measurements of activated sludge (mixed liquor and foam) and measurements of extension of aeration tank covered by foam surfaces.

The data obtained by using the above indicated methods are clearly correlated with the capability of activated sludge to produce foam. Nevertheless a different coherence between foam test measurement data and foam coverage of aeration tanks was encountered in comparison to that between hydrophobicity measurement data and foam coverage of aeration tanks due to the hydraulic regime of surface.
The Oxidation State of a Protein Observed Molecule‐by‐Molecule
Authors: Schmauder Ralf , Librizzi Fabio , Canters Gerard W. , Schmidt Thomas , Aartsma Thijs J.
Published: July 2005

We report the observation of the redox state of the blue copper protein azurin on the single‐molecule level. The fluorescence of a small fluorophore attached to the protein is modulated by the change in absorption of the copper center via fluorescence resonance energy transfer (FRET). In our model system, the fluorescence label Cy5 was coupled to azurin from Pseudomonas aeruginosa via cysteine K27C. The Cy5 fluorescence was partially quenched by the absorption of the copper center of azurin in its oxidized state. In the reduced state, absorption is negligible, and thus no quenching occurs. We report on single‐molecule measurements, both in solution by using fluorescence correlation spectroscopy (FCS) combined with fluorescence intensity distribution analysis (FIDA), and on surfaces by using wide‐field fluorescence microscopy.
Inflammation and the etiology of type 2 diabetes
Authors: Sjöholm Åke , Nyström Thomas
Published: July 2005

Type 2 diabetes is increasingly common worldwide and is beginning to strike younger age groups. Almost 90% of all patients with diabetes show insulin resistance, which also precedes the first symptoms of diabetes. The mechanisms underlying the development of insulin resistance are not well understood. In recent years, several studies have been published that implicate subclinical chronic inflammation as an important pathogenetic factor in the development of insulin resistance and type 2 diabetes. This opens new perspectives for diagnosis and treatment of early insulin resistance and incipient glucose intolerance.

Surrogate markers for this low‐grade chronic inflammation include CRP, IL‐6 and TNF‐α. Some antidiabetic agents, for example, glitazones that reduce insulin resistance, and insulin itself, reduce inflammation. Conversely, antiinflammatory drugs (ASA/NSAID) may improve glucose tolerance. Vasoactive drugs that are often prescribed to people with diabetes, for example, statins and ACE inhibitors/angiotensin receptor antagonists, also counteract inflammation and reduce the risk of type 2 diabetes. More specific and sensitive biomarkers should be identified, which may predict early disturbances in insulin sensitivity and cardiovascular risk. Also, inflammatory signalling pathways need to be explored in greater detail, and may form the basis of drugable targets against the epidemic of insulin resistance and atherosclerosis. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis of Leprapinic Acid, Calycine and Analogues by Sequential “[3+2] Cyclization/Suzuki/Lactonization” Reactions
Authors: Ahmed Zafar , Albrecht Uwe , Langer Peter
Published: July 2005

Calycine and analogues were prepared on the basis of Suzuki cross‐coupling reactions of γ‐alkylidene‐α‐hydroxybutenolides – readily available by cyclization of 1,3‐dicarbonyl dianions or 1,3‐bis(silyl enol ether)s with oxalyl derivatives – and subsequent boron tribromide‐mediated lactonization. Leprapinic acid was prepared by chemoselective boron tribromide‐mediated deprotection of permethylated leprapinic acid. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Conformational Study of GPI Anchors: the Common Oligosaccharide GPI Anchor Backbone
Authors: Chevalier Franck , Lopez‐Prados Javier , Perez Serge , Martín‐Lomas Manuel , Nieto Pedro M.
Published: July 2005

The solution three‐dimensional structure of pseudopentasaccharide 6, which constitutes the product from the GPI‐PLD cleavage of a GPI anchor, has been studied using a protocol which involves a systematic search of the conformational space around the glycosidic linkages, a thorough molecular dynamics study with explicit water molecules and a full NMR analysis study of intramolecular hydrogen bonding in solution. The results indicate that 6 exists in an extended conformation with a considerable flexibility compatible with a hinge‐like conformational motion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Nifedipine pretreatment reduces vibration‐induced vascular damage
Authors: Curry Brian D. , Govindaraju Sandya R. , Bain James L. W. , Zhang Lin Ling , Yan Ji‐Geng , Matloub Hani S. , Riley Danny A.
Published: July 2005

A rat‐tail vibration model of hand‐arm vibration was employed to test whether preemptive administration of nifedipine (5 mg/kg) to block vasoconstriction prevents vibration‐induced arterial damage. The tails of vibrated and nifedipine‐pretreated vibrated Sprague‐Dawley rats were exposed continuously to 4 h of 60‐HZ vibration at 49 m/s2 rms. In nonvibrated anesthetized rats, the ventral tail arteries were bathed for 15 min in situ in 1 mM epinephrine or 1 mM norepinephrine to induce structural changes indicative of intense vasoconstriction. Arteries were processed for light and electron microscopy 45 min after treatment. Compared to sham control, 4‐h vibration significantly (P < 0.01) reduced lumen size, generated endothelial disruption (7.0 ± 2.6%), elevated nuclear factor of activated T cells c3 (NFATc3) expression in endothelial and smooth muscle cells, and increased smooth muscle cell vacuolization. The findings demonstrate that blockage of vibration‐induced vasoconstriction with nifedipine prevents acute vascular damage. Smooth muscle and endothelial cells structurally altered by vasoconstriction are rendered susceptible to damage by vibration. Muscle Nerve, 2005
Dimethyl sulfone in human cerebrospinal fluid and blood plasma confirmed by one‐dimensional 1H and two‐dimensional 1H‐13C NMR
Authors: Engelke Udo F. H. , Tangerman Albert , Willemsen Michèl A. A. P. , Moskau Detlef , Loss Sandra , Mudd S. Harvey , Wevers Ron A.
Published: July 2005

1H‐NMR spectroscopy at 500 MHz was used to confirm that a previously unidentified singlet resonance at 3.14 ppm in the spectra of cerebrospinal fluid and plasma samples corresponds to dimethyl sulfone (DMSO2). A triple resonance inverse cryogenic NMR probe, with pre‐amplifier and the RF‐coils cooled to low temperature, was used to obtain an 1H‐13C HSQC spectrum of CSF containing 8 µM (753 ng/ml) DMSO2. The 1H‐13C correlation signal for DMSO2 was assigned by comparison with the spectrum from an authentic reference sample. In plasma and CSF from healthy controls, the concentration of DMSO2 ranged between 0 and 25 µmol/l. The concentration of DMSO2 in plasma from three of four patients with severe methionine adenosyltransferase I/III (MAT I/III) deficiency was about twice the maximum observed for controls. Thus, DMSO2 occurs as a regular metabolite at low micromolar concentrations in cerebrospinal fluid and plasma. It derives from dietary sources, from intestinal bacterial metabolism and from human endogenous methanethiol metabolism. Copyright © 2005 John Wiley & Sons, Ltd.
A simulation‐based study of wireless sensor network middleware
Authors: Wolenetz Matthew , Kumar Rajnish , Shin Junsuk , Ramachandran Umakishore
Published: July 2005

Future wireless sensor networks (WSNs) will transport high‐bandwidth, low‐latency streaming data, and will host sophisticated processing, such as image fusion and object tracking,in‐networkon sensor network nodes. Recent middleware proposals provide capabilities for in‐network processing, reducing energy drain based on communication costs alone. However, hosting complex processing on WSN nodes incurs additional processing energy and latency costs that impact network lifetime and application performance. There is a need for a WSN planning framework to explore energy saving and application performance trade‐offs for models of future sensor networks that account for processing costs in addition to communication costs. In this work, we present a simulation framework to analyze the interplay between resource requirements for compute‐ and communication‐intensive in‐network processing for streaming applications. We simulate a surveillance application workload with middleware capabilities for data fusion, adaptive policy‐driven migration of data fusion computation across network nodes, and prefetching of streaming data inputs for fusion processing. Our study sheds light on application figures of merit such as latency, throughput, and lifetime with respect to migration policy and node CPU and radio characteristics. Copyright © 2005 John Wiley & Sons, Ltd.
Node placement for triangular mesh generation by Monte Carlo simulation
Authors: Zhang Hanzhou , Smirnov Andrei V.
Published: July 2005

A new approach of node placement for unstructured mesh generation is proposed. It is based on the Monte Carlo method to position nodes for triangular or tetrahedral meshes. Surface or volume geometries to be meshed are treated as atomic systems, and mesh nodes are considered as interacting particles. By minimizing system potential energy with Monte Carlo simulation, particles are placed into a near‐optimal configuration. Well‐shaped triangles or tetrahedra can then be created after connecting the nodes by constrained Delaunay triangulation or tetrahedrization. The algorithm is simple, easy to implement, and works in an almost identical way for 2D and 3D meshing. Copyright © 2005 John Wiley & Sons, Ltd.
Photofabrication of surface relief gratings from azobenzene containing perfluorocyclobutane aryl ether polymer
Authors: Chun Chaemin , Ghim Jieun , Kim Mi‐Jeong , Kim Dong Yu
Published: July 2005

An azobenzene based perfluorocyclobutane (PFCB) aryl ether polymer, poly[4‐(phenylazo)triphenylamine‐1,2‐hexafluorocyclobutyl ether], was synthesized by using a palladium catalyzed amination reaction and the 2π + 2π cyclodimerization of 4‐[(trifluorovinyl)oxy]bromobenzene. This polymer was designed and synthesized to permit azo chromophores to be incorporated, thus introducing photoinduced dynamic behavior into the PFCB containing polymer structure. The polymer exhibited a Tg of about 122 °C, and the maximum absorption of the azo chromophores was 407 nm in the film state. A thin film was prepared through a spin coating process, and the rapid growth of diffraction efficiency was then achieved by irradiation with an interference beam. The efficient formation of holographic surface relief gratings was also verified from AFM images, which show regularly defined and aligned grating structures. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3525–3532, 2005
Synthesis of poly(vinylidene fluoride) (PVdF)/silica hybrids having interpenetrating polymer network structure by using crystallization between PVdF chains
Authors: Ogoshi Tomoki , Chujo Yoshiki
Published: July 2005

High transparent and homogeneous poly(vinylidene fluoride) (PVdF)/silica hybrids were obtained by using an in‐situ interpenetrating polymer network (IPN) method. The simultaneous formation of PVdF gel resulting from the physical cross‐linking and silica gel from sol–gel process prevented the aggregation of PVdF in silica gel matrix. To form the physical cross‐linking between PVdF chains, the cosolvent system of dimethylformaide (DMF) and γ‐butyrolactone was used. The obtained PVdF/silica hybrids had an entangled combination of physical PVdF gel and silica gel, which was called a “complete‐ IPN” structure. The physical cross‐linking between PVdF chains in silica gel matrix was confirmed by differential scanning calorimetry (DSC) measurements. The miscibility between PVdF and silica phase was examined by scanning electron microscopy (SEM) and tapping mode atomic force microscopy (TM‐AFM) measurements. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3543–3550, 2005
Synthesis and characterization of a poly(N‐isopropylacrylamide) with β‐cyclodextrin as pendant groups
Authors: Liu Yu‐Yang , Fan Xiao‐Dong , Zhao YA‐Bing
Published: July 2005

A novel linear poly(N‐isopropylacrylamide) (PNIPA) with β‐cylodextrin (β‐CD) moiety (PNIPA‐β‐CD) was synthesized by the conjugation of β‐CD carrying amino groups (EDA‐β‐CD) onto PNIPA with epoxy groups (P(NIPA‐co‐GMA), Mn = 3.86 × 104), and the related reaction conditions are investigated. PNIPA‐β‐CD was characterized by means of IR, NMR and UV spectroscopes, element analysis, and differential scanning calorimetry (DSC). The number‐average molecular weight (Mn) and the β‐CD content of the obtained PNIPA‐β‐CD are 4.87 × 104 and 18.8 wt %, respectively. PNIPA‐β‐CD can not only respond to temperature stimuli but also include guest molecules. Lower critical solution temperature (LCST) of aqueous PNIPA‐β‐CD solution is similar to that of PNIPA. The association constant (Ka) for PNIPA‐β‐CD with methyl orange (MO) is 2.4 × 103 L mol−1 at pH 1.4, which is comparable to that of EDA‐β‐CD (Ka = 2.9 × 103 L mol−1). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3516–3524, 2005
Photovoltaic behavior of structures based on nanocrystalline semiconductor oxides
Authors: Vigil E. , Zumeta I. , Ayllón J. A. , González B. , Domènech X. , Domínguez C.
Published: July 2005

Contributions to the improvement of TiO2 photoelectrodes are presented. When using as underlying layer a thin film obtained by microwave‐activated chemical bath deposition (MW‐CBD), photoelectrodes with a two‐layer TiO2 structure supersede the one‐layer structure. This is explained on the basis of TiO2‐conducting oxide contact. Also, the TiO2 sensitization issue is considered. A new simple way to sensitize TiO2 with copper oxide is used. This technology is perspective for trying to eliminate liquid electrolyte in DSSC and possibly, for water photolysis. Photoelectrodes formed with a copper oxide–porous TiO2 heterostructure work in the visible part of the spectrum and require no bias for photocurrent generation. Photovoltaic behavior is characterized by the spectral photocurrent dependence and time response. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electromechanical Transducers at the Nanoscale: Actuation and Sensing of Motion in Nanoelectromechanical Systems (NEMS)
Authors: Ekinci K. L.
Published: July 2005

Electromechanical devices are rapidly being miniaturized, following the trend in commercial transistor electronics. Miniature electromechanical devices—now with dimensions in the deep sub‐micrometer range—are envisioned for a variety of applications as well as for accessing interesting regimes in fundamental physics. Among the most important technological challenges in the operation of these nanoelectromechanical systems (NEMS) are the actuation and detection of their sub‐nanometer displacements at high frequencies. In this Review, we shall focus on this most central concern in NEMS technology: realization of electromechanical transducers at the nanoscale. The currently available techniques to actuate and detect NEMS motion are introduced, and the accuracy, bandwidth, and robustness of these techniques are discussed.