bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Active Gold Nanoclusters on Iron Oxide Supports for CO Oxidation
Authors: Herzing Andrew A. , Kiely Christopher J. , Carley Albert F. , Landon Philip , Hutchings Graham J.
Published: September 2008

Gold nanocrystals absorbed on metal oxides have exceptional properties in oxidation catalysis, including the oxidation of carbon monoxide at ambient temperatures, but the identification of the active catalytic gold species among the many present on real catalysts is challenging. We have used aberration-corrected scanning transmission electron microscopy to analyze several iron oxide–supported catalyst samples, ranging from those with little or no activity to others with high activities. High catalytic activity for carbon monoxide oxidation is correlated with the presence of bilayer clusters that are ∼0.5 nanometer in diameter and contain only ∼10 gold atoms. The activity of these bilayer clusters is consistent with that demonstrated previously with the use of model catalyst systems.
Internally Generated Cell Assembly Sequences in the Rat Hippocampus
Authors: Pastalkova Eva , Itskov Vladimir , Amarasingham Asohan , Buzsáki György
Published: September 2008

A long-standing conjecture in neuroscience is that aspects of cognition depend on the brain's ability to self-generate sequential neuronal activity. We found that reliably and continually changing cell assemblies in the rat hippocampus appeared not only during spatial navigation but also in the absence of changing environmental or body-derived inputs. During the delay period of a memory task, each moment in time was characterized by the activity of a particular assembly of neurons. Identical initial conditions triggered a similar assembly sequence, whereas different conditions gave rise to different sequences, thereby predicting behavioral choices, including errors. Such sequences were not formed in control (nonmemory) tasks. We hypothesize that neuronal representations, evolved for encoding distance in spatial navigation, also support episodic recall and the planning of action sequences.
Human-Specific Gain of Function in a Developmental Enhancer
Authors: Prabhakar Shyam , Visel Axel , Akiyama Jennifer A. , Shoukry Malak , Lewis Keith D. , Holt Amy , Plajzer-Frick Ingrid , Morrison Harris , FitzPatrick David R. , Afzal Veena , Pennacchio Len A. , Rubin Edward M. , Noonan James P.
Published: September 2008

Changes in gene regulation are thought to have contributed to the evolution of human development. However, in vivo evidence for uniquely human developmental regulatory function has remained elusive. In transgenic mice, a conserved noncoding sequence (
HACNS1
) that evolved extremely rapidly in humans acted as an enhancer of gene expression that has gained a strong limb expression domain relative to the orthologous elements from chimpanzee and rhesus macaque. This gain of function was consistent across two developmental stages in the mouse and included the presumptive anterior wrist and proximal thumb. In vivo analyses with synthetic enhancers, in which human-specific substitutions were introduced into the chimpanzee enhancer sequence or reverted in the human enhancer to the ancestral state, indicated that 13 substitutions clustered in an 81–base pair module otherwise highly constrained among terrestrial vertebrates were sufficient to confer the human-specific limb expression domain.
Flood or Drought: How Do Aerosols Affect Precipitation?
Authors: Rosenfeld Daniel , Lohmann Ulrike , Raga Graciela B. , O'Dowd Colin D. , Kulmala Markku , Fuzzi Sandro , Reissell Anni , Andreae Meinrat O.
Published: September 2008

Aerosols serve as cloud condensation nuclei (CCN) and thus have a substantial effect on cloud properties and the initiation of precipitation. Large concentrations of human-made aerosols have been reported to both decrease and increase rainfall as a result of their radiative and CCN activities. At one extreme, pristine tropical clouds with low CCN concentrations rain out too quickly to mature into long-lived clouds. On the other hand, heavily polluted clouds evaporate much of their water before precipitation can occur, if they can form at all given the reduced surface heating resulting from the aerosol haze layer. We propose a conceptual model that explains this apparent dichotomy.
Response to Comment on "Fire-Derived Charcoal Causes Loss of Forest Humus"
Authors: Wardle David A. , Nilsson Marie-Charlotte , Zackrisson Olle
Published: September 2008

We find the suggestion that substantial charcoal loss occurred in the humus-charcoal mixtures implausible and discuss why complexing of soluble carbon released from the mixtures by underlying mineral soil should be minor. This exchange highlights our limited knowledge about charcoal effects on native soil carbon, indicating that strong advocacy for charcoal addition to offset CO2emissions remains premature.
Apobec3
Encodes
Rfv3
, a Gene Influencing Neutralizing Antibody Control of Retrovirus Infection
Authors: Santiago Mario L. , Montano Mauricio , Benitez Robert , Messer Ronald J. , Yonemoto Wes , Chesebro Bruce , Hasenkrug Kim J. , Greene Warner C.
Published: September 2008

Recovery from Friend virus 3 (
Rfv3
) is a single autosomal gene encoding a resistance trait that influences retroviral neutralizing antibody responses and viremia. Despite extensive research for 30 years, the molecular identity of
Rfv3
has remained elusive. Here, we demonstrate that
Rfv3
is encoded by
Apobec3. Apobec3
maps to the same chromosome region as
Rfv3
and has broad inhibitory activity against retroviruses, including HIV. Not only did genetic inactivation of
Apobec3
convert
Rfv3
-resistant mice to a susceptible phenotype, but
Apobec3
was also found to be naturally disabled by aberrant messenger RNA splicing in
Rfv3
-susceptible strains. The link between
Apobec3
and neutralizing antibody responses highlights an
Apobec3
-dependent mechanism of host protection that might extend to HIV and other human retroviral infections.
The Crystal Structure of a Mammalian Fatty Acid Synthase
Authors: Maier Timm , Leibundgut Marc , Ban Nenad
Published: September 2008

Mammalian fatty acid synthase is a large multienzyme that catalyzes all steps of fatty acid synthesis. We have determined its crystal structure at 3.2 angstrom resolution covering five catalytic domains, whereas the flexibly tethered terminal acyl carrier protein and thioesterase domains remain unresolved. The structure reveals a complex architecture of alternating linkers and enzymatic domains. Substrate shuttling is facilitated by flexible tethering of the acyl carrier protein domain and by the limited contact between the condensing and modifying portions of the multienzyme, which are mainly connected by linkers rather than direct interaction. The structure identifies two additional nonenzymatic domains: (i) a pseudo-ketoreductase and (ii) a peripheral pseudo-methyltransferase that is probably a remnant of an ancestral methyltransferase domain maintained in some related polyketide synthases. The structural comparison of mammalian fatty acid synthase with modular polyketide synthases shows how their segmental construction allows the variation of domain composition to achieve diverse product synthesis.
The Tobacco Strategy Entrenched
Authors: Cranor Carl F.
Published: September 2008

Doubt Is Their Product
. How Industry's Assault on Science Threatens Your Health.
By David Michaels
. Oxford University Press, Oxford, 2008. 384 pp. $27.95, £14.99. ISBN 9780195300673.

The author describes the prevalence and effectiveness of industry efforts to promote doubt and fan controversy in order to undermine research that supports public health and environmental regulations.
Boys with a Simple Delayed Puberty Reach Their Target Height
Authors: Cools B.L.M. , Rooman R. , Op De Beeck L. , Du Caju M.V.L.
Published: September 2008

Introduction: Final height in boys with delayed puberty is thought to be below target height. This conclusion, however, is based on studies that included patients with genetic short stature. We therefore studied final height in a group of 33 untreated boys with delayed puberty with a target height >–1.5 SDS. Methods: Standing height, sitting height, weight and arm span width were measured in each patient. Final height was predicted by the method of Greulich and Pyle using the tables of Bailey and Pinneau for retarded boys at their bone age (PAH1) and the tables of Bailey and Pinneau for average boys plus six months (PAH2). Results: Mean final height (175.8 ± 6.5 cm) was appropriate for the mean target height (174.7 ± 4.5 cm). The prediction method of Bailey and Pinneau overestimated the final height by 1.4 cm and the modified prediction method slightly underestimated the final height (–0.15 cm). Conclusion: Boys with untreated delayed puberty reach a final height appropriate for their target height. Final height was best predicted by the method of Bailey and Pinneau using the tables for average boys at their bone age plus six months.
Circulating Levels of High-Sensitivity C-Reactive Protein and Soluble Markers of Vascular Endothelial Cell Activation in Growth Hormone-Deficient Adolescents
Authors: Lanes Roberto , Marcano Henry , Villaroel Omar , Gunczler Peter , Morillo Edgar , Paoli Mariela , Perez Marvelys , Maulino Nora , Palacios Anselmo
Published: September 2008

Background/Aims: Significant endothelial dysfunction as determined by lower flow-mediated vasodilation of the brachial artery was recently reported by us in growth hormone-deficient (GHD) adolescents. The circulating concentrations of markers of vascular endothelial cell and platelet activation and their relationship to inflammatory markers have not been previously evaluated in this group of patients. Objective: To assess the relationship between circulating levels of high-sensitivity C-reactive protein (CRP) and soluble markers of vascular endothelial cell activation in GHD adolescents. Design/Methods: Twenty-eight GHD children on GH treatment with a chronological age of 15.7 ± 2.6 years and 16 untreated GHD adolescents with a chronological age of 16.6 ± 3.3 years were studied. Concentrations of CRP, as an inflammatory marker, were measured in all patients and the association between CRP and the fasting soluble markers of vascular endothelial cell activation intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin and P-selectin levels was evaluated. Sixteen healthy adolescents with a mean chronological age of 15.1 ± 2.2 years served as controls. Results: CRP and P-selectin levels were significantly higher in untreated GHD adolescents than in treated GHD subjects or in healthy controls (p < 0.02), while VCAM-1 concentrations were increased in both untreated and treated GHD adolescents when compared to controls (p < 0.007). E-selectin and ICAM-1 levels were similar in all three groups. CRP was found to be associated with BMI (r: 0.62; p < 0.001), P-selectin (r: 0.43; p < 0.01), E-selectin (r: 0.27; p < 0.03), ICAM-1 (r: 0.23; p < 0.05) and VCAM-1 (r: 0.40; p < 0.001) concentrations in untreated GHD adolescents and with P-selectin (r: 0.88; p < 0.001) and E-selectin (r: 0.29; p < 0.01) in treated GHD subjects. A weak inverse association was observed in a subgroup of patients between brachial artery endothelium-dependent dilation and P-selectin (r: –0.56; p < 0.07). Conclusions: Low-grade inflammation as manifested by increased circulating levels of CRP seems to be associated with the early activation of vascular endothelial cells in GHD adolescents
Increased Fetal Plasma and Amniotic Fluid Erythropoietin Concentrations: Markers of Intrauterine Hypoxia
Authors: Teramo Kari A. , Widness John A.
Published: September 2008

Tissue hypoxia is the major stimulus of erythropoietin (EPO) synthesis in fetuses and adults. Since EPO does not cross the placenta and is not stored, fetal plasma and amniotic fluid levels indicate EPO synthesis and elimination. Acutely, the rate and magnitude of the increase in plasma EPO levels correlate with the intensity of hypoxia. Amniotic fluid EPO levels correlate with cord plasma levels in normal and abnormal pregnancies, with fetal plasma EPO levels in humans averaging 2.6 times higher than the corresponding amniotic fluid EPO levels. Recent experimental and clinical studies demonstrate that EPO has neuroprotective effects related to its anti-apoptotic and vascular growth-promoting properties. Although under basal conditions the fetal kidneys are the main site of EPO production, during hypoxia recent experimental data indicate an important role of the placenta. Amniotic fluid EPO levels have been shown to increase exponentially during fetal hypoxia in preeclamptic, diabetic and Rh-immunized pregnancies, to correlate inversely with cord blood pH, pO2 and base excess and to predict neonatal morbidities and NICU admission. As an indicator of chronic intrauterine hypoxia, fetal EPO measurements have increased our knowledge about the pathogenesis and importance of intrauterine growth restriction, macrosomia, diabetic pregnancy, prolonged pregnancy, meconium staining, fetal hemorrhage, fetal anemia, maternal smoking and alcohol consumption, abnormal fetal heart rate and abnormal Doppler flow patterns. While the clinical utility of fetal amniotic fluid and plasma EPO measurements in the management of high-risk pregnancies and their offspring is promising, adequately powered clinical trials are urgently needed.
Another Abnormal Trait in the Serotonin Metabolism Path in Intrauterine Growth-Restricted Infants
Authors: Hernandez-Rodriguez Jorge , Meneses Laura , Herrera Rocio , Manjarrez Gabriel
Published: September 2008

Background: The present study was aimed to obtain information on the interaction kinetics of L-tryptophan (L-Trp) with plasma albumin from normal, intrauterine growth-restricted (IUGR) and nutritionally recovered (NR) newborn infants. Methods: A case study cohort was planned in 37 newborns during the first 3 months of life. At birth two groups were formed. The first group included 20 newborns with IUGR. The control group (C) included 17 appropriate for gestational age newborns. At 30 days of age, 9 infants of the IUGR group showed a return to normal of the anthropometric parameters, these infants formed the NR group. Free, bound and total L-Trp were measured. To assess binding kinetics albumin was freed of fatty acids and tested in mole to mole samples from IUGR, NR and control babies. Results: Plasma free L-Trp was increased, Kd (dissociation constant) elevated and Bmax (maximal binding)decreased in IUGR patients up to postnatal day 90. These changes remained even after nutritional recovery. Conclusions: Abnormal kinetics of L-Trp binding to albumin explains the increased availability of this precursor amino acid in the plasma of IUGR infants. This finding corroborates previous results in IUGR rats and newborn babies, indicating enhanced potential for brain serotonergic synthesis.
Fetal Growth Influences Lymphocyte Subset Counts at Birth: The Generation R Study
Authors: Duijts Liesbeth , Bakker-Jonges Liesbeth E. , Labout Joost A.M. , Jaddoe Vincent W.V. , Hofman Albert , Steegers Eric A.P. , van Dongen Jacques J.M. , Hooijkaas Herbert , Moll Henriëtte A.
Published: September 2008

Background: Preterm born and low-birth-weight infants are at risk for severe infections in infancy. It has been suggested that these infants have an immature immune system. Objective:To assess the associations of gestational age, birth weight and fetal growth with absolute lymphocyte subset counts at birth. Methods: This study was conducted in 571 infants participating in the Generation R Study, a population-based prospective cohort study from fetal life onwards. Gestational age and birth weight were obtained from midwives and hospital registries. Fetal growth was defined as increase in weight between late pregnancy and birth. Lymphocytes and T lymphocyte subset counts in cord blood were determined by 6-color flow cytometry. Multivariate linear regression models with adjustment for gender, maternal education, smoking, alcohol use, fever and mode of delivery were applied. Results: Per week increase of gestational age, T, B and NK lymphocyte counts increased with 3, 5 and 6%, respectively (p < 0.05). Helper, cytotoxic and naive T lymphocyte counts increased with 3, 4 and 5%, respectively (p < 0.05), but memory T lymphocyte counts did not. Increased birth weight and fetal growth were significantly associated with higher B lymphocyte counts, independent of gestational age, but not with the other lymphocyte subset counts. Conclusions: Lymphocyte subset counts increase with prolonged gestation, suggesting an ongoing development of the immune system. Birth weight and fetal growth seem to influence only B lymphocyte counts.
Causes and Circumstances of Neonatal Deaths in 108 Consecutive Cases over a 10-Year Period at the Children’s Hospital of Lucerne, Switzerland
Authors: Berger T.M. , Hofer A.
Published: September 2008

Background: Neonatal deaths still represent the largest percentage of overall childhood mortality. Many deaths of neonates are preceded by end-of-life decisions; however, decision-making practices have been reported to vary widely from country to country. Objectives: To analyze principal causes and circumstances of all consecutive neonatal deaths at our institution over a 10-year period. Methods: All neonates who had died either in the delivery room (DR) or the neonatal intensive care unit (NICU) between January 1, 1997 and December 31, 2006 were identified. Demographic information, principal causes and circumstances of death were abstracted from the individual medical records. Results: There were approximately 72,000 live births in the catchment area of our center with 15,150 deliveries occurring at the Women’s Hospital of Lucerne. Of the 108 deaths identified, 29 occurred in the DR (DR mortality rate 0.2%) and 79 in the NICU (NICU mortality rate 2.3%). The majority of DR deaths occurred in the setting of primary nonintervention and were related to extreme prematurity (n = 20), lethal congenital malformations (n = 6) and trisomy 13 (n = 2). One patient with severe perinatal asphyxia died despite full resuscitative efforts. In the NICU, overall mortality rate was inversely related to gestational age (GA). Cardiovascular and respiratory system failures were the predominant causes of death in premature infants with a GA <32 weeks, whereas CNS catastrophes accounted for the majority of deaths in the more mature NICU population. End-of-life decisions were common with less than 10% of deaths occurring despite maximal intensive care. Conclusions: In our perinatal center, primary nonintervention and redirection of care are the most common circumstances of death in neonates. This reflects our belief that, apart from futility, quality-of-life considerations are an important part of decision making in neonatology.
Effects of Dietary Conjugated Linoleic Acid in Advanced Experimental Polycystic Kidney Disease
Authors: Scatliff Candice E. , Bankovic-Calic Neda , Ogborn Malcolm R. , Aukema Harold M.
Published: September 2008

Background/Aims: Several dietary interventions, including those involving conjugated linoleic acid (CLA), slow progression of polycystic kidney disease (PKD) when initiated in the early stages of disease in Han:SPRD-cy rats. However, in humans, kidney disease is often undetected until extensive renal injury has developed. The objective of this study therefore was to determine whether initiating dietary CLA intervention in advanced PKD would slow disease progression. Methods: Adult male Han:SPRD-cy rats with advanced kidney disease were fed diets with or without 1% CLA for 16 weeks. Disease progression was assessed by serum urea, proteinuria, and creatinine clearance, and morphological and immunohistochemical measurements for pathologic change. Results: Renal injury was lower in the PKD rats given CLA compared to those given the control diet as indicated by a reduction in inflammation (42% less), fibrosis (28% less), oxidative damage (30% less) and proliferating cells (35% less). Diet had no effect on body, kidney, or liver weight, serum urea, serum creatinine, creatinine clearance, proteinuria, or cyst volume. Conclusions: Late dietary intervention with CLA reduced some disease-associated pathologies, but did not alter renal function in adult Han:SPRD-cy rats. The long-term anti-inflammatory, antioxidant, and antiproliferative benefits of CLA in advanced kidney disease remain to be determined.
Sex Chromatin in Hair Roots
Authors: Schmid W.
Published: September 2008

A simple method is described by which sex chromatin can be studied in the cells of the external root sheath of single hairs. From a human capital hair many thousands of scorable nuclei can be obtained. Since this material is suitable for orcein staining, preparations are ready for analysis within a few minutes. Qualitative and quantitative results are presented from control persons and multiple-X individuals. The method is most convenient for studies in various mammals, and samples of results are given for some rodent and carnivore species.
Chronology and Pattern of Human Chromosome Replication
Authors: Sofuni T. , Sandberg A.A.
Published: September 2008

The autoradiographic behavior of normal male and female chromosomes in blood leukocytes at various stages in the DNA synthesis period (S period) has been investigated with 3H-thymidine. One X chromosome in female cells and the Y in male cells do not replicate their DNA or do so to a limited extent, 12 h before metaphase, when most of the other chromosomes are undergoing replication at a substantial rate. Asynchrony among the chromosomes is evident at that time. Furthermore, the X in female cells and the Y in male cells are the last chromosomes to finish their DNA replication. The replication of an elongated No. 1 autosome in a patient with primary amenorrhea has been compared to that of its normal homolog. The secondary constriction area, particularly prominent in the elongated No. 1, is the last area to finish replication in both the abnormal and normal No. 1 autosomes and is one of the latest segments in the human complement to finish replication. The leukocyte generation time was found to be 18 h or more in the presence of phytohemagglutinin (PHA). The data presented further delineate the time sequence and pattern of chromosomal replication in normal human leukocytes.
Variation in Relative Lengths of Early- and Late-Replicating Portions of X Chromosomes of the Chinese Hamster (Cricetulus griseus)
Authors: Corey M.J. , Boyes J.W. , Yerganian G.
Published: September 2008

In the Chinese hamster comparison of heterochromatic and euchromatic arms of X1 and X2 chromosomes and an autosomal pair (No. 3) of similar length by means of relative regression coefficients has indicated that the heterochromatic, or late-replicating, elements vary less per unit length than euchromatic elements of similar length and, therefore, do not maintain a constant percentage of the total complement length.
High throughput thin film materials science
Authors: Barber Z. H. , Blamire M. G.
Published: September 2008

Combinatorial techniques, in which a library of chemical formulations is scanned for specific activity, have been used extensively to expedite the discovery phase of pharmaceutical compounds. Such techniques have more recently come to prominence in relation to the discovery of novel functional inorganic materials using methods of thin film deposition. Here the aim is to prepare a thin film sample containing a spread of compositions so that localised measurements can explore a range of properties across the phase diagram. The application of high throughput thin film techniques to the optimisation of materials properties has its roots in earlier studies which exploited position-dependent process variables to assist optimisation protocols. Indeed, we argue here that one of the biggest challenges facing combinatorial materials science is to ensure that property variations can be ascribed solely to composition changes, by achieving sufficient control over the inevitable variation in other process parameters. This review provides a discussion of the range of parameters, including composition, which can be controllably varied as a function of position during thin film growth. In addition to the growth techniques themselves, we discuss the requirements placed on materials diagnostics and property measurements, which are essential for the high throughput capability to be realised.
Effect of gauge length in superplastic tensile tests
Authors: Bate P. S. , Ridley N. , Sotoudeh K.
Published: September 2008

There is an incentive to obtain data on the mechanical behaviour of superplastic materials to model superplastic forming processes, in particular to help reduce forming times. The usual method involves tensile tests at elevated temperatures without extensometry. However, inhomogeneous deformation has a large effect on the apparent stress–strain behaviour and elongation to failure. Strain distributions have been measured in tensile specimens of superplastic Al–4·5Mg alloy with different gauge lengths, and on a non-superplastic Al–1Mn alloy, all tested at 530°C. There was considerable drawing-in of material from the specimen ends to the gauge in the superplastic alloy, but not in the Al–Mn material. The draw-in meant that the apparent elongation of the Al–4·5Mg alloy almost doubled when the gauge length to width ratio was reduced from 4 to 1 and the apparent stress–strain behaviour was also significantly affected by the gauge geometry.
Development of hypoeutectoid graphitic steel for wires
Authors: Banerjee K. , Venugopalan T.
Published: September 2008

Hypoeutectoid graphitic steels with BN as prime nucleating site for graphite nucleation were developed for improvement of drawability of wires. Al2O3 also acted as nucleation site for graphite. The steel chemistry has played an important role for BN formation and thus dictated the behaviour of graphite formation and tensile properties after graphitising annealing. The steels are with a low yield ratio of ∼0·5 while percentage elongation is in the range of 23–25% and percentage reduction in area is in the range of 45–51%.
Assimilation of French-Canadian Names into New England Speech: Notes from a Vermont Cemetery
Authors: Adams Michael
Published: September 2008

AbstractHeadstones in St Mary's Cemetery in Middlebury, Vermont, and entries in the marriage repertoire of the Church of the Assumption of the Blessed Virgin Mary in the same town illustrate patterns of Canadian French accommodation to New England phonology as French-speaking immigrants established themselves there, as well as French-Canadian adaptation to New England identity and the social motivations for allowing given and family names to mark cultural assimilation and, alternatively, resisting change of name as such a marker.
Rational Fear or Represented Malaise: A Crucial Test of Two Paradigms Explaining Fear of Crime
Authors: Elchardus Mark , De Groof Saskia , Smits Wendy
Published: September 2008

In explanations offered for fear of crime, two different paradigms can be distinguished. The first considers fear of crime as a rational reaction to crime and victimization; the other views such fear as a representation of more general feelings of malaise. The paradigms suggest different research strategies and offer different explanations for the same empirical observations. The choice of paradigm therefore determines the meaning of the empirical findings and hence the policy implications that can be drawn from them. In this article, the authors describe the paradigms, illustrate the way in which they offer different explanations for the same observations, and try to empirically discriminate between them on the basis of crucial tests. The tests are performed on data for the Flemish (Belgian) population aged nineteen to thirty-six. The results support the view that fear of crime or feelings of insecurity should be seen mainly as a consequence of, on one hand, general feelings of malaise, vulnerability, and helplessness that can have many origins and, on the other hand, exposure to processes of communication that highlight crime and the risk of victimization.
Patriarchy? Paternalism? Motherhood Discourses in Trials of Crimes against Children
Authors: Gurevich Liena
Published: September 2008

This article analyzes two recent trials of women accused of killing their infants. The legal strategies that employ gender of the defendant as a resource for constructing narratives of the offense are explored. This is achieved through analysis of discourses of the transcripts of the defendants' trials. Two salient discourses, patriarchal and paternalist, are identified in the article. Patriarchal discourses are characterized by the equation of womanhood and motherhood and by the overtness of the ranking of men over women. The paternalist gender management expresses itself in deference to the professional discourses that define motherhood— medical, psychiatric, and administrative. The evidence presented suggests that maternal trials of crimes against children provide a conduit for discussion of the issues that matter—the place and importance of motherhood in contemporary society. What is taking place in these trials reflects cultural neurosis over the ambiguity with regard to the definitions of the foundational relationship of mother and child. The article suggests that the trials of mothers accused of harming their children are symbolic of the problems involved in the contemporary regulation of mothering.
Facilitators and Advocates: How Mainline Protestant Clergy Respond to Homosexuality
Authors: Cadge Wendy , Wildeman Christopher
Published: September 2008

This article analyzes how thirty mainline Protestant clergy who addressed homosexuality in their local congregations positioned themselves within their congregations on the issue. Regardless of their positions, all of the pastors first situated the root causes of religious and broader societal conflicts over homosexuality in an emotion, fear, which they understood as their congregants' fears of sexuality, gay and lesbian people, misinterpreting scripture, and the unknown. Based on their understandings of these fears, clergy then drew from their individual cultural “toolkits” to construct personal “strategies of action” via personal identities as facilitators, quiet advocates, or more outward advocates around homosexuality in their congregations. The authors analyze the processes by which clergy constructed these identities, with particular attention to the strategies of action attendant within each identity category. This analysis advances substantive knowledge about how clergy respond to homosexuality in local congregations and theoretical knowledge about how religious leaders construct personal identities as one “strategy of action” (among many) when addressing controversial social issues in local religious organizations.
Working Connections: Shop Floor Networks and Union Leadership
Authors: Grannis Rick , Smith David A. , Stepan-Norris Judith
Published: September 2008

Leadership is not a unitary phenomenon. While many variations are possible, leadership comes in at least two forms: Emergent leaders who represent those whom they lead and imposed leaders who do not derive their authority from those they lead. This is especially true of the workplace. Management leaders, while often selected from among workers, are imposed on them from above; in contrast, union leadership claims to emerge from and to represent those they intend to lead. Union leadership, however, has embedded within it an apparent contradiction. A labor union needs to be as effective in mobilizing workers as it is democratic in representing them. This article explores the microfoundations of representative and effective leadership by analyzing workplace social networks and shows that, in our setting at least, aspiring union representatives are situated to represent well while aspiring forepersons are not. Thus, the structures of informal social networks in work groups create a social fabric that allows unions to simultaneously be a “town hall” and an “army.”
Stem Cell Identification and Sorting Using the Hoechst 33342 Side Population (SP)
Authors: Goodell Margaret A.
Published: September 2008

This unit describes the use of Hoechst 33342 to identify and purify murine hematopoietic stem cells, the so‐called side population. Three properties of the dye contribute to the ability to distinguish stem cells in this way. Hoechst is a DNA‐binding dye. It has at least two binding modes that result in different spectral properties, allowing resolution of multiple populations by viewing fluorescence at two wavelengths simultaneously. The ability to discriminate SP cells is based on the differential efflux of the dye by a multi‐drug‐like transporter. Particular attention is given to the critical aspects of Hoechst concentration, cell concentration, staining time, and staining temperature.
Use of Microsphere‐Supported Phospholipid Membranes for Analysis of Protein‐Lipid Interactions
Authors: Gilbert Gary E.
Published: September 2008

Many proteins bind to phospholipid membranes in order to gain or modify function. As an example, blood coagulation proteins must bind to phosphatidylserine‐containing membranes in order to gain procoagulant activity. The flow cytometry approaches described in this unit provide versatile assays for equilibrium and kinetic binding studies to measure essential membrane‐binding properties. These assays are rapid, require only small quantities of the protein of interest, and can evaluate binding interactions in complex, physiological mixtures, including blood plasma and tissue culture media.
Multiplexed SNP Genotyping Using Primer Single‐Base Extension (SBE) and Microsphere Arrays
Authors: Deshpande Alina , Valdez Yolanda , Nolan John P.
Published: September 2008

Single‐nucleotide polymorphisms (SNPs), genome sites with single‐base sequence differences between individual chromosomes, are the most common type of genetic variation. Single‐base changes can result in disease phenotypes, confer susceptibility or resistance to toxins or pathogens, or serve as markers for distinct allelic segments of DNA, making SNPs an important emerging tool in both basic and clinical research. This unit presents detailed protocols for multiplexed SNP genotyping using primer single‐base extension (SBE) adapted to microspheres and flow cytometry. The methods described are best suited for typing a modest number of SNPs in a large number of samples. The Basic Protocol describes extension of the genotyping primers by one nucleotide, a labeled dideoxyribonucleotide that reveals the nucleotide base at that position on the template strand. The extended primers are then captured onto microspheres bearing an oligonucleotide “address” that is the reverse complement of a sequence on the 5′ end of the genotyping primers and subsequently measured using flow cytometry.
BeadCons: Detection of Nucleic Acid Sequences by Flow Cytometry
Authors: Horejsh Douglas , Martini Federico , Capobianchi Maria Rosaria
Published: September 2008

Molecular beacons are single‐stranded nucleic acid structures with a terminal fluorophore and a distal, terminal quencher. These molecules are typically used in real‐time PCR assays, but have also been conjugated with solid matrices. This unit describes protocols related to molecular beacon–conjugated beads (BeadCons), whose specific hybridization with complementary target sequences can be resolved by cytometry. Assay sensitivity is achieved through the concentration of fluorescence signal on discrete particles. By using molecular beacons with different fluorophores and microspheres of different sizes, it is possible to construct a fluid array system with each bead corresponding to a specific target nucleic acid. Methods are presented for the design, construction, and use of BeadCons for the specific, multiplexed detection of unlabeled nucleic acids in solution. The use of bead‐based detection methods will likely lead to the design of new multiplex molecular diagnostic tools.
Scientific Uncertainty in Social Debates Around Risk
Authors: Driedger S. Michelle
Published: September 2008

Quantitative risk assessments based on scientific understandings of a risk issue are often used in managing risk controversies in a policy domain. However, in several areas of risk, particularly in an environment and health domain, managing uncertainties in scientific knowledge is difficult and complex. It is important to understand how the production and use of scientific evidence can be understood as a social process and how scientific evidence may be used in regulatory decision making.
Risk and the Media
Authors: Mistry Bhavnita , Driedger S. Michelle
Published: September 2008

The news media has long been recognized as an important social player in civil society in shaping public discourse concerning current events, particularly in the communication of science, policy, and risk issues. While the media may not tell us what our thoughts should be, it has considerable power in influencing the same by virtue of what it does, and does not, report. This article explores how the media report and frame risk issues.
Considerations in Planning for Successful Risk Communication
Authors: Jardine Cynthia G.
Published: September 2008

Successful risk communication does not occur serendipitously—it is the result of careful planning and consideration of multiple needs and objectives. Some considerations for planning for successful risk communication are presented here. However, this list is neither fully comprehensive nor exhaustive. The best overall guidance is to try to view the risk through the eyes of those who may legitimately and rationally view the nature and consequences of the risk differently. Evoking an empathetic understanding of different perspectives of risk, together with the application of good judgment about the nature of the risk, is ultimately the key to initiating a productive dialogue on risks.
Stakeholder Participation in Risk Management Decision Making
Authors: Jardine Cynthia G.
Published: September 2008

Stakeholder participation in risk management processes is becoming increasingly recognized as a means of producing decisions that are responsive to varying interests and values, including those of the community. Some considerations for planning for successful stakeholder involvement are outlined. Goals against which stakeholder participation efforts can be evaluated are also provided. However, the “right” process of participation must be determined on the basis of the nature of the risk and the impact of the decision.
Axiomatic Measures of Risk and Risk‐Value Models
Authors: Jia Jianmin , Dyer James S. , Butler John C.
Published: September 2008

This article provides a review of risk and risk‐value models that lead to decision making by explicitly trading off between risk and value. We begin with a discussion of a preference‐dependent measure of risk that is compatible with traditional expected utility theory, and therefore lends itself to an examination of how individuals perceive risky gambles as well as how they choose among them. Further, this risk measure can be the basis for generalizing models of decision making based on the intuitively appealing notion of trading off between risk and value. Based on the two‐attribute expected utility axioms, this risk‐value framework has much more flexibility in modeling preferences than the traditional single‐attribute expected utility theory. Specifically, we describe three useful classes of decision models: moments risk‐value models, exponential risk‐value models, and generalized disappointment models. These decision models unify two streams of research: one in developing preference models and the other in modeling risk judgments. They can also provide prescriptive guidance for those people who are willing to deviate from the traditional expected utility preference models and make their decisions based on risk‐value trade‐offs, as in financial decision making.
Precautionary Principles: Definitions, Issues, and Implications for Risky Choices
Authors: Ricci Paolo F.
Published: September 2008

This paper deals with several legal and risk‐based aspects of making precautionary decision in the public interest. It addresses European Union, US, and other statements of regulatory precaution that have been used to make environmental decisions. The purpose of this article is to discuss how the methods in quantitative risk analysis (QRA) can help understand the impact of prospective a precautionary decisions by providing a sound risk management framework
Use of Decision Support Techniques for Information System Risk Management
Authors: Buckshaw Donald L.
Published: September 2008

Identifying and understanding security risks for information system design or evaluation is very challenging. Making decisions about accepting or mitigating these risks through a rational, traceable, and understandable process is even harder. Quantitative risk analysis techniques can help stakeholders understand and communicate risk‐informed design decisions even when the stakeholders have conflicting objectives. Quantitative risk analysis also helps stakeholders understand security, cost, and functionality trade‐off decisions in repeatable process. This paper discusses the roles of stakeholders in risk analysis, the advantages and disadvantages of quantitative risk analysis, basic cyber risk decision support concepts and processes, and the mathematical definitions of risk for information systems. This paper recommends the use of properly constructed quantitative risk analysis models and discourages the use of semiquantitative risk analysis models.
Air Pollution Risk
Authors: Smith Richard L.
Published: September 2008

This article reviews the literature on health effects of air pollution, with a primary focus on time series studies but also covers prospective studies and case‐crossover designs. It also covers some of the controversies created by these studies and concludes with a brief review of air pollution standards in the United States.
Change Point Analysis
Authors: West Ronnie Webster
Published: September 2008

This entry provides a brief introduction to the statistical methodology called
change point analysis
, which is oft used in risk assessment. The goal of change point analysis is to model changes in the characteristics of a response variable over a range of a predictor variable. The discussion below is framed by two simple examples from the risk assessment literature where the response characteristic of interest is the mean response. The examples illustrate two simple change point methods for detecting the location of the change point in terms of the predictor variable and the nature of the change in the mean response before and after the change point. More complicated change point methods are also discussed briefly.
Detection Limits
Authors: Helsel Dennis R.
Published: September 2008

Detection limits are established within a chemical laboratory to designate low‐level data that cannot be distinguished from a zero concentration. Higher limits also are used to denote data with low, nonzero concentrations that are too imprecise to report as distinct numbers. Data below both types of limits are reported to the customer as a “nondetect” (<10). Here, the definitions and uses of detection limits are outlined, and methods for using nondetect data in exposure assessments are explained.
Environmental Carcinogenesis Risk
Authors: Ryan Louise
Published: September 2008

A significant proportion of cancer cases are likely to be attributable to the environment, especially when broadly interpreted to include lifestyle choices such as smoking and diet, as well as chemical exposures encountered in the workplace, air, water, or in our food. This entry briefly reviews risk analytic aspects of environmental carcinogenesis.
Environmental Hazard
Authors: Beaubier Jeff , Nussbaum Barry D.
Published: September 2008

An environmental hazard is any condition, process, or state adversely affecting the environment. Environmental hazards manifest as physical or chemical pollution in air, water, and soils. Environmental hazards can cause widespread harm to humans and the physical environment. Three specific ones are discussed: lead, an element historically used in many products causing neurological problems; PCBs, or polychlorinated biphenyls, a group of nearly indestructible molecules with cancer‐causing properties; Asbestos, a widely used flame retardant which leads to cancers with long latency periods.
Environmental Health Risk
Authors: Khalili Nasrin R.
Published: September 2008

Risk is defined as the probability that a substance or situation will produce harm under specified conditions. Risk can be assessed with regards to safety, human health, ecology, public welfare, and goodwill. Environmental risk assessment involves both risk assessment and management of natural and technological hazards by estimating the potential impact of a chemical, physical, microbiological, or psychosocial hazard on a specified human population or ecological system. Environmental health assessment focuses on the aspects of public health and is concerned with the factors (contaminants and hazards), circumstances (exposure scenarios), and conditions in the environment. Health risk assessment process utilizes a series of assumptions, preferably in a conservative range, about the chemical hazards, exposure scenarios, and the toxicological factors in order to characterize the risks with a minimum level of uncertainty. The environmental health risk assessment provides guidelines for assessing human health risks from environmental hazards.
Statistics for Environmental Mutagenesis
Authors: Piegorsch Walter W.
Published: September 2008

In experiments studying the effects of environmental stimuli on biological organisms, major endpoints of interest include damage to genetic components such as deoxyribonucleic acid (DNA). DNA damage as represented by mutagenic insult(s) is perhaps the most varied of any toxicological endpoint, since the potential mechanisms of genetic damage are so numerous. Statistical issues associated with mutagenicity experiments include construction of models to characterize dose–response and other features of genetic damage, sample size determinations/study design, and the selection of statistical approaches associated with these models and methods; these are briefly discussed
Environmental Health Risk Assessment
Authors: Stern Alan H.
Published: September 2008

Quantitative health risk assessment is a tool for making predictions about the impact of substances in the environment on health. Despite the use of scientific principles and a reliance on the most appropriate data from the scientific literature, risk assessment, in the strict sense of the word, is not, by itself, a science. Two different forms of quantitative risk assessment are practiced. One form can be referred to assafety assessment, which seeks to identify the largest level of exposure or dose that can be reasonably expected to be without adverse effect. The other form seeks to quantify the risk associated with any exposure or dose of an environmental agent. In the United States, this form of risk assessment is generally applied to carcinogens. The classical structure of formal environmental health risk assessments comprises of four interdependent steps: hazard identification; dose–response assessment; exposure assessment; and risk characterization. Recent advances in conducting environmental health risk assessments include the use of the benchmark dose approach in lieu of the no observed adverse effect level (NOAEL)/lowest observed adverse effect level (LOAEL) determination, the use of probabilistic analysis in place of single value estimates for risk assessment variables, and progress toward harmonization of cancer and noncancer endpoints.
Environmental Risk Regulation
Authors: Hammitt James K.
Published: September 2008

Environmental risk regulation is intended to limit the harm that individuals and firms would otherwise inflict on others by releasing pollutants to the environment. Regulation requires characterizing the harm from alternative levels of pollution, setting standards to govern the level of a pollutant in the environment, and choosing a regulatory mechanism to govern the compliance behavior of polluters.