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OBJECTIVE: Late-onset sepsis (occurring after 3 days of age) is an important problem in very low birth weight (VLBW) infants. To determine the current incidence of late-onset sepsis, risk factors for disease, and the impact of late-onset sepsis on subsequent hospital course, we evaluated a cohort of 6956 VLBW (401-1500 g) neonates admitted to the clinical centers of the National Institute of Child Health and Human Development Neonatal Research Network over a 2-year period (1998-2000). METHODS: The National Institute of Child Health and Human Development Neonatal Research Network maintains a prospective registry of all VLBW neonates admitted to participating centers within 14 days of birth. Expanded infection surveillance was added in 1998. RESULTS: Of 6215 infants who survived beyond 3 days, 1313 (21%) had 1 or more episodes of blood culture-proven late-onset sepsis. The vast majority of infections (70%) were caused by Gram-positive organisms, with coagulase-negative staphylococci accounting for 48% of infections. Rate of infection was inversely related to birth weight and gestational age. Complications of prematurity associated with an increased rate of late-onset sepsis included patent ductus arteriosus, prolonged ventilation, prolonged intravascular access, bronchopulmonary dysplasia, and necrotizing enterocolitis. Infants who developed late-onset sepsis had a significantly prolonged hospital stay (mean length of stay: 79 vs 60 days). They were significantly more likely to die than those who were uninfected (18% vs 7%), especially if they were infected with Gram-negative organisms (36%) or fungi (32%). CONCLUSIONS: Late-onset sepsis remains an important risk factor for death among VLBW preterm infants and for prolonged hospital stay among VLBW survivors. Strategies to reduce late-onset sepsis and its medical, social, and economic toll need to be addressed urgently.

30 pages, 8 figures, 1 table, supporting information https://doi.org/10.1371/journal.pone.0308461.-- Data Availability: The data underlying the results presented in the study are available through ONC’s Oceans 3.0 data management system (https://data.oceannetworks.ca/home)

Depression is perhaps the most frequent cause of emotional suffering in later life and significantly decreases quality of life in older adults. In recent years, the literature on late-life depression has exploded. Many gaps in our understanding of the outcome of late-life depression have been filled. Intriguing findings have emerged regarding the etiology of late-onset depression. The number of studies documenting the evidence base for therapy has increased dramatically. Here, I first address case definition, and then I review the current community- and clinic-based epidemiological studies. Next I address the outcome of late-life depression, including morbidity and mortality studies. Then I present the extant evidence regarding the etiology of depression in late life from a biopsychosocial perspective. Finally, I present evidence for the current therapies prescribed for depressed elders, ranging from medications to group therapy.

BACKGROUND: Controversy exists about the timing of the initiation of parenteral nutrition in critically ill adults in whom caloric targets cannot be met by enteral nutrition alone. METHODS: In this randomized, multicenter trial, we compared early initiation of parenteral nutrition (European guidelines) with late initiation (American and Canadian guidelines) in adults in the intensive care unit (ICU) to supplement insufficient enteral nutrition. In 2312 patients, parenteral nutrition was initiated within 48 hours after ICU admission (early-initiation group), whereas in 2328 patients, parenteral nutrition was not initiated before day 8 (late-initiation group). A protocol for the early initiation of enteral nutrition was applied to both groups, and insulin was infused to achieve normoglycemia. RESULTS: Patients in the late-initiation group had a relative increase of 6.3% in the likelihood of being discharged alive earlier from the ICU (hazard ratio, 1.06; 95% confidence interval [CI], 1.00 to 1.13; P=0.04) and from the hospital (hazard ratio, 1.06; 95% CI, 1.00 to 1.13; P=0.04), without evidence of decreased functional status at hospital discharge. Rates of death in the ICU and in the hospital and rates of survival at 90 days were similar in the two groups. Patients in the late-initiation group, as compared with the early-initiation group, had fewer ICU infections (22.8% vs. 26.2%, P=0.008) and a lower incidence of cholestasis (P<0.001). The late-initiation group had a relative reduction of 9.7% in the proportion of patients requiring more than 2 days of mechanical ventilation (P=0.006), a median reduction of 3 days in the duration of renal-replacement therapy (P=0.008), and a mean reduction in health care costs of €1,110 (about $1,600) (P=0.04). CONCLUSIONS: Late initiation of parenteral nutrition was associated with faster recovery and fewer complications, as compared with early initiation. (Funded by the Methusalem program of the Flemish government and others; EPaNIC ClinicalTrials.gov number, NCT00512122.).

In this review, we examine the oft-made claim that peer-relationship difficulties in childhood predict serious adjustment problems in later life. The article begins with a framework for conceptualizing and assessing children's peer difficulties and with a discussion of conceptual and methodological issues in longitudinal risk research. Following this, three indexes of problematic peer relationships (acceptance, aggressiveness, and shyness/withdrawal) are evaluated as predictors of three later outcomes (dropping out of school, criminality, and psychcpathology). The relation between peer difficulties and later maladjustment is examined in terms of both the consistency and strength of prediction. A review and analysis of the literature indicates general support for the hypothesis that children with poor peer adjustment are at risk for later life difficulties. Support is clearest for the outcomes of dropping out and criminality. It is also clearest for low acceptance and aggressiveness as predictors, whereas a link between shyness/withdrawal and later maladjustment has not yet been adequately tested. The article concludes with a critical discussion of the implicit models that have guided past research in this area and a set of recommendations for the next generation of research on the risk

Using 6 longitudinal data sets, the authors estimate links between three key elements of school readiness--school-entry academic, attention, and socioemotional skills--and later school reading and math achievement. In an effort to isolate the effects of these school-entry skills, the authors ensured that most of their regression models control for cognitive, attention, and socioemotional skills measured prior to school entry, as well as a host of family background measures. Across all 6 studies, the strongest predictors of later achievement are school-entry math, reading, and attention skills. A meta-analysis of the results shows that early math skills have the greatest predictive power, followed by reading and then attention skills. By contrast, measures of socioemotional behaviors, including internalizing and externalizing problems and social skills, were generally insignificant predictors of later academic performance, even among children with relatively high levels of problem behavior. Patterns of association were similar for boys and girls and for children from high and low socioeconomic backgrounds.

Apolipoprotein E is immunochemically localized to the senile plaques, vascular amyloid, and neurofibrillary tangles of Alzheimer disease. In vitro, apolipoprotein E in cerebrospinal fluid binds to synthetic beta A4 peptide (the primary constituent of the senile plaque) with high avidity. Amino acids 12-28 of the beta A4 peptide are required. The gene for apolipoprotein E is located on chromosome 19q13.2, within the region previously associated with linkage of late-onset familial Alzheimer disease. Analysis of apolipoprotein E alleles in Alzheimer disease and controls demonstrated that there was a highly significant association of apolipoprotein E type 4 allele (APOE-epsilon 4) and late-onset familial Alzheimer disease. The allele frequency of the APOE-epsilon 4 in 30 random affected patients, each from a different Alzheimer disease family, was 0.50 +/- 0.06; the allele frequency of APOE-epsilon 4 in 91 age-matched unrelated controls was 0.16 +/- 0.03 (Z = 2.44, P = 0.014). A functional role of the apolipoprotein E-E4 isoform in the pathogenesis of late-onset familial Alzheimer disease is suggested.

The apolipoprotein E type 4 allele (APOE-epsilon 4) is genetically associated with the common late onset familial and sporadic forms of Alzheimer's disease (AD). Risk for AD increased from 20% to 90% and mean age at onset decreased from 84 to 68 years with increasing number of APOE-epsilon 4 alleles in 42 families with late onset AD. Thus APOE-epsilon 4 gene dose is a major risk factor for late onset AD and, in these families, homozygosity for APOE-epsilon 4 was virtually sufficient to cause AD by age 80.

Since the last comprehensive review in 1974, the Health Belief Model (HBM) has continued to be the focus of considerable theoretical and research attention. This article presents a critical review of 29 HBM-related investigations published during the period of 1974-1984, tabulates the findings from 17 studies conducted prior to 1974, and provides a summary of the total 46 HBM studies (18 prospective, 28 retrospective). Twenty-four studies examined preventive-health behaviors (PHB), 19 explored sick-role behaviors (SRB), and three addressed clinic utilization. A "significance ratio" was constructed which divides the number of positive, statistically-significant findings for an HBM dimension by the total number of studies reporting significance levels for that dimension. Summary results provide substantial empirical support for the HBM, with findings from prospective studies at least as favorable as those obtained from retrospective research. "Perceived barriers" proved to be the most powerful of the HBM dimensions across the various study designs and behaviors. While both were important overall, "perceived susceptibility" was a stronger contributor to understanding PHB than SRB, while the reverse was true for "perceived benefits." "Perceived severity" produced the lowest overall significance ratios; however, while only weakly associated with PHB, this dimension was strongly related to SRB. On the basis of the evidence compiled, it is recommended that consideration of HBM dimensions be a part of health education programming. Suggestions are offered for further research.

Apolipoprotein E, type epsilon 4 allele (APOE epsilon 4), is associated with late-onset familial Alzheimer's disease (AD). There is high avidity and specific binding of amyloid beta-peptide with the protein ApoE. To test the hypothesis that late-onset familial AD may represent the clustering of sporadic AD in families large enough to be studied, we extended the analyses of APOE alleles to several series of sporadic AD patients. APOE epsilon 4 is significantly associated with a series of probable sporadic AD patients (0.36 +/- 0.042, AD, versus 0.16 +/- 0.027, controls [allele frequency estimate +/- standard error], p = 0.00031). Spouse controls did not differ from CEPH grandparent controls from the Centre d'Etude du Polymorphisme Humain (CEPH) or from literature controls. A large combined series of autopsy-documented sporadic AD patients also demonstrated highly significant association with the APOE epsilon 4 allele (0.40 +/- 0.026, p < or = 0.00001). These data support the involvement of ApoE epsilon 4 in the pathogenesis of late-onset familial and sporadic AD. ApoE isoforms may play an important role in the metabolism of beta-peptide, and APOE epsilon 4 may operate as a susceptibility gene (risk factor) for the clinical expression of AD.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLate-Metal Catalysts for Ethylene Homo- and CopolymerizationSteven D. Ittel, Lynda K. Johnson, and Maurice BrookhartView Author Information DuPont Central Research & Development, Wilmington, Delaware 19880-0328 Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290 Cite this: Chem. Rev. 2000, 100, 4, 1169–1204Publication Date (Web):March 25, 2000Publication History Received13 September 1999Published online25 March 2000Published inissue 1 April 2000https://pubs.acs.org/doi/10.1021/cr9804644https://doi.org/10.1021/cr9804644research-articleACS PublicationsCopyright © 2000 American Chemical SocietyRequest reuse permissionsArticle Views17048Altmetric-Citations2823LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Alkyls,Catalysts,Hydrocarbons,Ligands,Nickel Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTN-Heterocyclic Carbenes in Late Transition Metal CatalysisSilvia Díez-González†, Nicolas Marion‡†, and Steven P. Nolan*†§View Author Information Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain, and School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9ST, U.K.*[email protected]†Institute of Chemical Research of Catalonia.‡Present address: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.§University of St Andrews.Cite this: Chem. Rev. 2009, 109, 8, 3612–3676Publication Date (Web):July 9, 2009Publication History Received24 February 2009Published online9 July 2009Published inissue 12 August 2009https://pubs.acs.org/doi/10.1021/cr900074mhttps://doi.org/10.1021/cr900074mreview-articleACS PublicationsCopyright © 2009 American Chemical SocietyRequest reuse permissionsArticle Views36042Altmetric-Citations2763LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Addition reactions,Catalysts,Chemical reactions,Hydrocarbons,Ligands Get e-Alerts

Emerging adulthood is proposed as a new conception of development for the period from the late teens through the twenties, with a focus on ages 18-25. A theoretical background is presented. Then evidence is provided to support the idea that emerging adulthood is a distinct period demographically, subjectively, and in terms of identity explorations. How emerging adulthood differs from adolescence and young adulthood is explained. Finally, a cultural context for the idea of emerging adulthood is outlined, and it is specified that emerging adulthood exists only in cultures that allow young people a prolonged period of independent role exploration during the late teens and twenties.

Discourse in Late Modernity sets out to show that critical discourse analysis is strongly positioned to address empirical research and theory-building across the social sciences, particularly research and theory on the semiotic/linguistic aspects of the social world. It situates critical discourse analysis as a form of critical social research in relation to diverse theories from the philosophy of science to social theory and from political science to sociology and linguistics. First, the authors clarify the ontological and epistemological assumptions of critical discourse analysis - its view of what the social world consists of and how to study it - and, in so doing, point to the connections between critical discourse analysis and critical social scientific research more generally. Secondly, they relate critical discourse analysis to social theory, by creating a research agenda in contemporary social life on the basis of narratives of late modernity, particularly those of Giddens, Habermas, and Harvey as well as feminist and postmodernist approaches. Thirdly, they show the relevance of sociological work in the analysis of discursive aspects of social life, drawing on the work of Bourdieu and Bernstein to theorise the dialectic of social reproduction and change, and on post-structuralist, post-colonial and feminist work to theorise the dialectic of complexity and homogenisation in contemporary societies. Finally, they discuss the relationship between systemic-functional linguistics and critical discourse analysis, showing how the analytical strength of each can benefit from the other. * Sets out a new and distinctive theoretical grounding and research agenda for critical discourse analysis * Interdisciplinary in scope * Draws on a broad range of theories and approaches

The lives of people from age eighteen to twenty-nine change dramatically but recently this has change has become more profound and a new stage of life has developed. Known as "emerging adulthood", this stage is distinct from both the adolescence that precedes it and the young adulthood that comes in its wake. Rather than marrying and becoming parents in their early twenties, most people in industrialized societies now postpone these transitions until at least their late twenties. This book identifies and labels this period of limbo, exploration, instability, possibility, and self-focus. An increasing number of emerging adults emphasize the importance of meaningful and satisfying work to a degree not seen in prior generations. Marrying later and exploring more casual sexual relationships have created different hopes and fears concerning long-term commitments and the differences between love and sex. Emerging adults also face the challenge of defending their non-traditional lifestyles to parents and others outside their generation who have made more traditional choices. In contrast to previous portrayals of emerging adults, the book's research shows that they are particularly skilled at maintaining contradictory emotions - they are confident while still being wary, and optimistic in the face of large degrees of uncertainty.

Endotoxin, a constituent of Gram-negative bacteria, stimulates macrophages to release large quantities of tumor necrosis factor (TNF) and interleukin-1 (IL-1), which can precipitate tissue injury and lethal shock (endotoxemia). Antagonists of TNF and IL-1 have shown limited efficacy in clinical trials, possibly because these cytokines are early mediators in pathogenesis. Here a potential late mediator of lethality is identified and characterized in a mouse model. High mobility group-1 (HMG-1) protein was found to be released by cultured macrophages more than 8 hours after stimulation with endotoxin, TNF, or IL-1. Mice showed increased serum levels of HMG-1 from 8 to 32 hours after endotoxin exposure. Delayed administration of antibodies to HMG-1 attenuated endotoxin lethality in mice, and administration of HMG-1 itself was lethal. Septic patients who succumbed to infection had increased serum HMG-1 levels, suggesting that this protein warrants investigation as a therapeutic target.

OBJECTIVE: To compare the language abilities of earlier- and later-identified deaf and hard-of-hearing children. METHOD: We compared the receptive and expressive language abilities of 72 deaf or hard-of-hearing children whose hearing losses were identified by 6 months of age with 78 children whose hearing losses were identified after the age of 6 months. All of the children received early intervention services within an average of 2 months after identification. The participants' receptive and expressive language abilities were measured using the Minnesota Child Development Inventory. RESULTS: Children whose hearing losses were identified by 6 months of age demonstrated significantly better language scores than children identified after 6 months of age. For children with normal cognitive abilities, this language advantage was found across all test ages, communication modes, degrees of hearing loss, and socioeconomic strata. It also was independent of gender, minority status, and the presence or absence of additional disabilities. CONCLUSIONS: Significantly better language development was associated with early identification of hearing loss and early intervention. There was no significant difference between the earlier- and later-identified groups on several variables frequently associated with language ability in deaf and hard-of-hearing children. Thus, the variable on which the two groups differed (age of identification and intervention) must be considered a potential explanation for the language advantage documented in the earlier-identified group.

Cognitive load theory was introduced in the 1980s as an instructional design theory based on several uncontroversial aspects of human cognitive architecture. Our knowledge of many of the characteristics of working memory, long-term memory and the relations between them had been well-established for many decades prior to the introduction of the theory. Curiously, this knowledge had had a limited impact on the field of instructional design with most instructional design recommendations proceeding as though working memory and long-term memory did not exist. In contrast, cognitive load theory emphasised that all novel information first is processed by a capacity and duration limited working memory and then stored in an unlimited long-term memory for later use. Once information is stored in long-term memory, the capacity and duration limits of working memory disappear transforming our ability to function. By the late 1990s, sufficient data had been collected using the theory to warrant an extended analysis resulting in the publication of Sweller et al. (Educational Psychology Review, 10, 251–296, 1998). Extensive further theoretical and empirical work have been carried out since that time and this paper is an attempt to summarise the last 20 years of cognitive load theory and to sketch directions for future research.

Between 1974 and 1990 more than thirty countries in southern Europe, Latin America, East Asia, and Eastern Europe shifted from authoritarian to democratic systems of government. This global democratic revolution is probably the most important political trend in the late twentieth century. In The Third Wave, Samuel P. Huntington analyzes the causes and nature of these democratic transitions, evaluates the prospects for stability of the new democracies, and explores the possibility of more countries becoming democratic. The recent transitions, he argues, are the third major wave of democratization in the modem world. Each of the two previous waves was followed by a reverse wave in which some countries shifted back to authoritarian government. Using concrete examples, empirical evidence, and insightful analysis, Huntington provides neither a theory nor a history of the third wave, but an explanation of why and how it occurred.Factors responsible for the democratic trend include the legitimacy dilemmas of authoritarian regimes; economic and social development; the changed role of the Catholic Church; the impact of the United States, the European Community, and the Soviet Union; and the snowballing phenomenon: change in one country stimulating change in others. Five key elite groups within and outside the nondemocratic regime played roles in shaping the various ways democratization occurred. Compromise was key to all democratizations, and elections and nonviolent tactics also were central. New democracies must deal with the torturer problem and the praetorian problem and attempt to develop democratic values and processes. Disillusionment with democracy, Huntington argues, is necessary to consolidating democracy. He concludes the book with an analysis of the political, economic, and cultural factors that will decide whether or not the third wave continues. Several Guidelines for Democratizers offer specific, practical suggestions for initiating and carrying out reform. Huntington's emphasis on practical application makes this book a valuable tool for anyone engaged in the democratization process. At this volatile time in history, Huntington's assessment of the processes of democratization is indispensable to understanding the future of democracy in the world.