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Showing papers by "University of Connecticut published in 1998"


Journal ArticleDOI
TL;DR: In this article, the authors reconceptualize the firm-level construct absorptive capacity as a learning dyad-level measure, relative absorptive capacities, and test the model using a sample of pharmaceutical-biotechnology R&D alliances.
Abstract: Much of the prior research on interorganizational learning has focused on the role of absorptive capacity, a firm's ability to value, assimilate, and utilize new external knowledge. However, this definition of the construct suggests that a firm has an equal capacity to learn from all other organizations. We reconceptualize the firm-level construct absorptive capacity as a learning dyad-level construct, relative absorptive capacity. One firm's ability to learn from another firm is argued to depend on the similarity of both firms' (1) knowledge bases, (2) organizational structures and compensation policies, and (3) dominant logics. We then test the model using a sample of pharmaceutical–biotechnology R&D alliances. As predicted, the similarity of the partners' basic knowledge, lower management formalization, research centralization, compensation practices, and research communities were positively related to interorganizational learning. The relative absorptive capacity measures are also shown to have greater explanatory power than the established measure of absorptive capacity, R&D spending. © 1998 John Wiley & Sons, Ltd.

4,627 citations


Book
13 Mar 1998
TL;DR: Garrett as mentioned in this paper showed that globalization has strengthened the relationship between the political power of the left and organized labour and economic policies that reduce market-generated inequalities of risk and wealth, and macroeconomic outcomes in the era of global markets have been as good or better in strong left-labour regimes ('social democratic corporatism') as in other industrial countries.
Abstract: Geoffrey Garrett challenges the conventional wisdom about the domestic effects of the globalization of markets in the industrial democracies: the erosion of national autonomy and the demise of leftist alternatives to the free market. He demonstrates that globalization has strengthened the relationship between the political power of the left and organized labour and economic policies that reduce market-generated inequalities of risk and wealth. Moreover, macroeconomic outcomes in the era of global markets have been as good or better in strong left-labour regimes ('social democratic corporatism') as in other industrial countries. Pessimistic visions of the inexorable dominance of capital over labour or radical autarkic and nationalist backlashes against markets are significantly overstated. Electoral politics have not been dwarfed by market dynamics as social forces. Globalized markets have not rendered immutable the efficiency-equality trade-off.

1,470 citations


Journal ArticleDOI
TL;DR: Among men with symptoms of urinary obstruction and prostatic enlargement, treatment with finasteride for four years reduces symptoms and prostate volume, increases the urinary flow rate, and reduces the probability of surgery and acute urinary retention.
Abstract: Background Finasteride is known to improve urinary symptoms in men with benign prostatic hyperplasia, but the extent to which the benefit is sustained and whether finasteride reduces the incidence of related events, including the need for surgery and the development of acute urinary retention, are not known. Methods In this double-blind, randomized, placebo-controlled trial, we studied 3040 men with moderate-to-severe urinary symptoms and enlarged prostate glands who were treated daily with 5 mg of finasteride or placebo for four years. Symptom scores (on a scale of 1 to 34), urinary flow rates, and the occurrence of outcome events were assessed every four months in 3016 men. Prostate volume was measured in a subgroup of the men. Complete data on outcomes were available for 2760 men. Results During the four-year study period, 152 of the 1503 men in the placebo group (10 percent) and 69 of the 1513 men in the finasteride group (5 percent) underwent surgery for benign prostatic hyperplasia (reduction in risk with finasteride, 55 percent; 95 percent confidence interval, 41 to 65 percent). Acute urinary retention developed in 99 men (7 percent) in the placebo group and 42 men (3 percent) in the finasteride group (reduction in risk with finasteride, 57 percent; 95 percent confidence interval, 40 to 69 percent). Among the men who completed the study, the mean decreases in the symptom score were 3.3 in the finasteride group and 1.3 in the placebo group (P<0.001). Treatment with finasteride also significantly improved urinary flow rates and reduced prostate volume (P<0.001). Conclusions Among men with symptoms of urinary obstruction and prostatic enlargement, treatment with finasteride for four years reduces symptoms and prostate volume, increases the urinary flow rate, and reduces the probability of surgery and acute urinary retention.

1,060 citations


Journal ArticleDOI
TL;DR: The objective of this work is to survey and put in perspective the existing IMM methods for target tracking problems, with special attention to the assumptions underlying each algorithm and its applicability to various situations.
Abstract: The Interacting Multiple Model (IMM) estimator is a suboptimal hybrid filter that has been shown to be one of the most cost-effective hybrid state estimation schemes. The main feature of this algorithm is its ability to estimate the state of a dynamic system with several behavior modes which can "switch" from one to another. In particular, the IMM estimator can be a self-adjusting variable-bandwidth filter, which makes it natural for tracking maneuvering targets. The importance of this approach is that it is the best compromise available currently-between complexity and performance: its computational requirements are nearly linear in the size of the problem (number of models) while its performance is almost the same as that of an algorithm with quadratic complexity. The objective of this work is to survey and put in perspective the existing IMM methods for target tracking problems. Special attention is given to the assumptions underlying each algorithm and its applicability to various situations.

1,024 citations


Journal ArticleDOI
06 Mar 1998-Science
TL;DR: Overexpression of EDG-1 induced exaggerated cell-cell aggregation, enhanced expression of cadherins, and formation of well-developed adherens junctions in a manner dependent on SPP and the small guanine nucleotide binding protein Rho.
Abstract: The sphingolipid metabolite sphingosine-1-phosphate (SPP) has been implicated as a second messenger in cell proliferation and survival. However, many of its biological effects are due to binding to unidentified receptors on the cell surface. SPP activated the heterotrimeric guanine nucleotide binding protein (G protein)-coupled orphan receptor EDG-1, originally cloned as Endothelial Differentiation Gene-1. EDG-1 bound SPP with high affinity (dissociation constant = 8.1 nM) and high specificity. Overexpression of EDG-1 induced exaggerated cell-cell aggregation, enhanced expression of cadherins, and formation of well-developed adherens junctions in a manner dependent on SPP and the small guanine nucleotide binding protein Rho.

1,004 citations


Journal ArticleDOI
TL;DR: A review of the weaknesses in interpretation and the choice of information that has been used to argue against atmospheric Hg contamination can be found in this paper, where the authors examine the weaknesses of the information used to support the prevailing scientific view that natural geologic sources are the principal contributors of Hg.
Abstract: Elevated levels of mercury in aquatic environments remote from industrial sources have been broadly attributed to long-range atmospheric transport and deposition of anthropogenic Hg. Evidence in support of this prevailing scientific viewglobal biogeochemical Hg models, sedimentary archives of historic Hg fluxes, and geographic trends in soil Hghave been challenged as being insuf ficiently rigorous to rule out the alternative explanation that natural geologic sources are the principal contributors of Hg in remote locations. In this review, we examine the weaknesses in interpretation and the choice of information that has been used to argue against atmospheric Hg contamination. Analytical advances in measuring trace levels of environmental Hg have greatly narrowed estimates of natural Hg fluxes, providing a clear measure of the relative magnitude of anthropogenic Hg emissions and deposition. Recent experimental results indicate that diagenetic processes cannot explain the mounting number of lake sediment an...

972 citations


Book ChapterDOI
01 Jan 1998
TL;DR: In most cultures, there are strong standards regarding sexual behavior which differ for men and women, and cultural differences also affect the extent to which early sexual behavior is considered acceptable.
Abstract: Developing and implementing successful interventions often depend upon effectively addressing ethnicity and social class factors, as these influence sexual behavior and its risks. Sexual attitudes differ across cultures. In most cultures, there are strong standards regarding sexual behavior which differ for men and women. Cultural differences also affect the extent to which early sexual behavior is considered acceptable.

919 citations


Journal ArticleDOI
TL;DR: Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC), the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay.
Abstract: Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC) assay, the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay. There was a weak but significant linear correlation between serum ORAC and serum FRAP. There was no correlation either between serum ORAC and serum TEAC or between serum FRAP and serum TEAC. The effect of dilution on the serum TEAC value and the use of inhibition percentage at a fixed time, without considering the length of inhibition time in the quantitation of results, adversely affected the Randox-TEAC assay. The FRAP assay is simple and inexpensive but does not measure the SH-group-containing antioxidants. The ORAC assay has high specificity and responds to numerous antioxidants. By utilizing different extraction techniques in the ORAC assay, one can remove serum proteins and also make some gross differentiation between aqueous and lipid-soluble antioxidants. However, the ORAC assay requires ∼60 min more than the FRAP or Randox-TEAC assay to quantitate results.

873 citations


Journal ArticleDOI
TL;DR: There was suggestive evidence for a protective locus on chromosome 4 near the alcohol dehydrogenase genes, for which protective effects have been reported in Asian populations.
Abstract: Alcohol dependence is a leading cause of morbidity and premature death. Several lines of evidence suggest a substantial genetic component to the risk for alcoholism: sibs of alcoholic probands have a 3-8 fold increased risk of also developing alcoholism, and twin heritability estimates of 50-60% are reported by contemporary studies of twins. We report on the results of a six-center collaborative study to identify susceptibility loci for alcohol dependence. A genome-wide screen examined 291 markers in 987 individuals from 105 families. Two-point and multipoint nonparametric linkage analyses were performed to detect susceptibility loci for alcohol dependence. Multipoint methods provided the strongest suggestions of linkage with susceptibility loci for alcohol dependence on chromosomes 1 and 7, and more modest evidence for a locus on chromosome 2. In addition, there was suggestive evidence for a protective locus on chromosome 4 near the alcohol dehydrogenase genes, for which protective effects have been reported in Asian populations.

726 citations


Journal ArticleDOI
TL;DR: The data suggest that OT abnormalities may exist in autism, and that more direct investigation of central nervous system OT function is warranted, after making inferences to central OT functioning from peripheral measurement.

686 citations


Journal ArticleDOI
01 May 1998-BJUI
TL;DR: Although selenium shows no protective effects against the primary endpoint of squamous and basal cell carcinomas of the skin, the selenum-treated group had substantial reductions in the incidence of prostate cancer, and total cancer incidence and mortality that demand further evaluation in well-controlled prevention trials.
Abstract: Objective To test if supplemental dietary selenium is associated with changes in the incidence of prostate cancer. Patients and method A total of 974 men with a history of either a basal cell or squamous cell carcinoma were randomized to either a daily supplement of 200 μg of selenium or a placebo. Patients were treated for a mean of 4.5 years and followed for a mean of 6.5 years. Results Selenium treatment was associated with a significant (63%) reduction in the secondary endpoint of prostate cancer incidence during 1983–93. There were 13 prostate cancer cases in the selenium-treated group and 35 cases in the placebo group (relative risk, RR=0.37, P=0.002). Restricting the analysis to the 843 patients with initially normal levels of prostate-specific antigen (≤4 ng/mL), only four cases were diagnosed in the selenium-treated group and 16 cases were diagnosed in the placebo group after a 2 year treatment lag, (RR=0.26 P=0.009). There were significant health benefits also for the other secondary endpoints of total cancer mortality, and the incidence of total, lung and colorectal cancer. There was no significant change in incidence for the primary endpoints of basal and squamous cell carcinoma of the skin. In light of these results, the ‘blinded’ phase of this trial was stopped early. Conclusions Although selenium shows no protective effects against the primary endpoint of squamous and basal cell carcinomas of the skin, the selenium-treated group had substantial reductions in the incidence of prostate cancer, and total cancer incidence and mortality that demand further evaluation in well-controlled prevention trials.

Journal ArticleDOI
TL;DR: In this article, the authors quantified the carbon (C and ni- trogen (N) content of the forest floor and the top 15 cm of mineral soil and the rate of midsummer net N mineralization beneath six different tree species.
Abstract: In a northwestern Connecticut forest, we quantified the carbon (C) and ni- trogen (N) content of the forest floor and the top 15 cm of mineral soil and the rate of midsummer net N mineralization beneath six different tree species. There were large in- terspecific differences in forest floor depth and mass, in the size and distribution of C and N pools at varying soil depths, and in rates of midsummer net N mineralization and nitri- fication. Forest floor mass ranged from 3.2 kg/m 2 to 11.0 kg/m 2 and was smallest beneath sugar maple and largest beneath hemlock. The pool size of C in the forest floor ranged from 1.1 kg/m 2 to 4.4 kg/m 2 while the N content of the forest floor ranged from 83 g/m 2 to 229 g/m 2 . Forest floor C and N pools were smallest beneath sugar maple and highest beneath hemlock. Soil C:N ratios (range: 14.8-19.5) were lower beneath sugar maple, red maple, and white ash than beneath beech, red oak, and hemlock, whereas the opposite was true of the midsummer rate of net N mineralization (range: 0.91-2.02 g·m 22 ·28 d 21 ). The rate of net nitrification was positively correlated with the rate of net N mineralization. Interspecific differences in litter production and quality explain the large differences among species in the size of the forest floor C and N pools and in net N mineralization rates. The differences in the size and distribution of C and N pools beneath the different species suggest that the mechanisms regulating the process of species replacement in these forests will mediate the effects of anthropogenic, environmental changes in soil C and N dynamics.

Journal ArticleDOI
01 Jun 1998-Immunity
TL;DR: It is conceivable that in a less polymorphic era, when adaptive immune response was but a distant gleam in the evolutionary eye, the interaction of HSPs with macrophage-like cells, leading to stimulation of the macrophages to secrete IL-1 and other messengers, was the primary “innate” defense mechanism.

Journal ArticleDOI
TL;DR: In this article, the dewetting of polystyrene films on a silicon substrate is investigated as a function of film thickness, and the average amplitude of these undulations increases exponentially up to the film rupture point where the film's average amplitude becomes comparable to $h, as predicted by a capillary wave instability model.
Abstract: Dewetting of polystyrene films on a silicon substrate is investigated as a function of film thickness $h$. We observe the nucleation of holes in the early stage of dewetting for relatively thick films $(hg100\AA{})$, as observed previously, but the breakup of thinner films occurs through the growth of uniformly distributed surface undulations (``spinodal dewetting''). The average amplitude $\ensuremath{\delta}h$ of these undulations increases exponentially up to the film rupture point where $\ensuremath{\delta}h$ becomes comparable to $h$, as predicted by a capillary wave instability model.

Journal ArticleDOI
TL;DR: In this paper, the available information on the nuclear-fusion cross sections that are most important for solar energy generation and solar neutrino production is reviewed and analyzed, and best values for the low-energy cross-section factors and, wherever possible, estimates of the uncertainties are provided.
Abstract: We review and analyze the available information on the nuclear-fusion cross sections that are most important for solar energy generation and solar neutrino production. We provide best values for the low-energy cross-section factors and, wherever possible, estimates of the uncertainties. We also describe the most important experiments and calculations that are required in order to improve our knowledge of solar fusion rates.

Journal ArticleDOI
TL;DR: Alcohol, marijuana, and cocaine dependence and habitual smoking are all familial, and there is evidence of both common and specific addictive factors transmitted in families.
Abstract: Background Alcoholism and substance dependence frequently co-occur. Accordingly, we evaluated the familial transmission of alcohol, marijuana, and cocaine dependence and habitual smoking in the Collaborative Study on the Genetics of Alcoholism. Methods Subjects (n=1212) who met criteria for both DSM-III-R alcohol dependence and Feighner definite alcoholism and their siblings (n=2755) were recruited for study. A comparison sample was also recruited (probands, n=217; siblings, n=254). Subjects were interviewed with the Semi-Structured Assessment for the Genetics of Alcoholism. The familial aggregation of drug dependence and habitual smoking in siblings of alcohol-dependent and non–alcohol-dependent probands was measured by means of the Cox proportional hazards model. Results Rates of alcohol, marijuana, and cocaine dependence and habitual smoking were increased in siblings of alcohol-dependent probands compared with siblings of controls. For siblings of alcohol-dependent probands, 49.3% to 50.1% of brothers and 22.4% to 25.0% of sisters were alcohol dependent (lifetime diagnosis), but this elevated risk was not further increased by comorbid substance dependence in probands. Siblings of marijuana-dependent probands had an elevated risk of developing marijuana dependence (relative risk [RR], 1.78) and siblings of cocaine-dependent probands had an elevated risk of developing cocaine dependence (RR, 1.71). There was a similar finding for habitual smoking (RR, 1.77 in siblings of habitual-smoking probands). Conclusions Alcohol, marijuana, and cocaine dependence and habitual smoking are all familial, and there is evidence of both common and specific addictive factors transmitted in families. This specificity suggests independent causative factors in the development of each type of substance dependence.

Journal ArticleDOI
TL;DR: In this article, the authors used a simple model to determine whether VAs are likely to lead to efficient environmental protection and found that the overall impact on environmental quality could be positive or negative, depending on the allocation of bargaining power, the magnitude of the background threat, and the social cost of funds.

Journal ArticleDOI
TL;DR: In this article, the synthesis, characterization, and applications of porous manganese oxides during the last two years have been discussed, including the synthesis of porous tunnel structures, layered structures, and related materials.
Abstract: This review concerns the synthesis, characterization, and applications of porous manganese oxides during the last two years The synthesis of porous tunnel structures, layered structures, and related materials is discussed Both microporous and mesoporous systems materials are covered here Characterization discussed here focuses around structural studies The focus of the application sections include electrochemical and catalytic studies

Journal ArticleDOI
TL;DR: It is indicated that postpartum depression had a small but significant effect on children's cognitive and emotional development.


Journal ArticleDOI
TL;DR: In this article, the theoretical foundation of the psychological contract and its dimensions is further developed, and the dimensions of psychological contracts (stability, scope, tangibility, focus, time frame, particularism, multiple agency and volition) highlight the differences and similarities among alternative employment arrangements.
Abstract: In this paper, we have endeavored to integrate the literature on psychological contracts with the literature on contingent work arrangements We have further developed the theoretical foundation of the psychological contract and its dimensions After reviewing previous work on contingent employment, we illustrate how the dimensions of psychological contracts (stability, scope, tangibility, focus, time frame, particularism, multiple agency and volition) highlight the differences and similarities among alternative employment arrangements in a meaningful and parsimonious manner In doing so, we have sought to offer an alternative to the categorization of employment arrangements that has, thus far, made comparisons across studies difficult In addition, we argue that the dimensions of psychological contracts, more so than the content of these contracts, are more generalizable across various types of work arrangements, as well as across different types of jobs and across national boundaries Copyright © 1998 John Wiley & Sons, Ltd

MonographDOI
TL;DR: In this paper, the authors discuss the social movements and culture in Sweden, from the sixties to the nineties, from populism to the popular front, and the movements of black music from the New Negro to civil rights.
Abstract: Introduction 1. On social movements and culture 2. Taking traditions seriously 3. Making an alternative popular culture: from populism to the popular front 4. The movements of black music: from the New Negro to civil rights 5. Politics and music in the 1960s 6. From the sixties to the nineties: the case of Sweden 7. Structures of feeling and cognitive praxis.


Journal ArticleDOI
13 Feb 1998-Science
TL;DR: Experimental removal of mice, which eat moth pupae, demonstrated that moth outbreaks are caused by reductions in mouse density that occur when there are no acorns, and Experimental acorn addition increased mouse density.
Abstract: In eastern U.S. oak forests, defoliation by gypsy moths and the risk of Lyme disease are determined by interactions among acorns, white-footed mice, moths, deer, and ticks. Experimental removal of mice, which eat moth pupae, demonstrated that moth outbreaks are caused by reductions in mouse density that occur when there are no acorns. Experimental acorn addition increased mouse density. Acorn addition also increased densities of black-legged ticks, evidently by attracting deer, which are key tick hosts. Mice are primarily responsible for infecting ticks with the Lyme disease agent. The results have important implications for predicting and managing forest health and human health.

Journal ArticleDOI
TL;DR: In this article, soil acidity and exchangeable cations in the forest floor and upper 7.5 cm of mineral soil beneath the canopies of individual trees of six different species in a mixed-species forest in northwestern Connecticut.
Abstract: We quantified soil acidity and exchangeable cations in the forest floor and upper 7.5 cm of mineral soil beneath the canopies of individual trees of six different species in a mixed-species forest in northwestern Connecticut. Soil pH decreased in a sequence starting with sugar maple (Acer saccharum) . white ash (Fraxinus americana) . red maple (Acer rubrum) . beech (Fagus grandifolia) . red oak (Quercus rubra) . eastern hemlock (Tsuga canadensis). The differences among species were largest in the forest floor and the top 7.5 cm of mineral soil. Exchangeable Ca and Mg in the 0-7.5 cm mineral soil layer were significantly higher beneath sugar maple than all other species, with the exception of white ash. There were negligible differences among species in the quantity of exchangeable Ca and Mg in the forest floor. In the 0-7.5 cm mineral soil layer, exchangeable Ca was positively correlated with the content of unweathered Ca in the parent material, but the relationship differed among species. There was a large increase in exchangeable Ca in the soils beneath sugar maple but a negligible increase in the soils beneath hemlock and red maple. Exchangeable Al and Fe were highest beneath hemlock and lowest beneath sugar maple. The differences in pH and exchangeable cations between sugar maple and hemlock are likely due to interspecific differences in the introduction of acidity (e.g., organic acids) and Ca uptake and allocation. Observing an association between tree species and specific soil chemical properties within mixed-species stands implies that changes in the distribution and abundance of tree species alters the spatial and temporal pattern of soil acidity and cation cycling in this forest.

Journal ArticleDOI
TL;DR: Smoking and diabetes have been identified as risk factors, especially diabetics with poor metabolic control, a long duration of the disease, and extensive subgingival calculus.
Abstract: Recent epidemiologic surveys and studies have provided important information on the prevalence, extent, and severity of periodontal diseases in the United States. Over 50% of adults had gingivitis on an average of 3 to 4 teeth. Subgingival calculus was present in 67% of the population. Adult periodontitis, measured by the presence of periodontal pockets ≥ 4 mm, was found in about 30% of the population on an average of 3 to 4 teeth. Severe pockets ≥ 6 mm were found in less than 5% of the population. Attachment loss ≥ 3 mm was found in 40% of the population. Gingival recession accounted for a significant amount of attachment loss. The prevalence of early-onset periodontitis ranged from less than 1% in 14- to 17-year-olds to 3.6% in young adults aged 18 to 34. Extensive and severe periodontitis was much more prevalent in minorities, people with less than a high school education, and those who had seen a dentist infrequently and had subgingival calculus. Smoking and diabetes have been identified as risk facto...

Journal ArticleDOI
Wei Li1
TL;DR: The authors proposed a new model of ethnic settlement, the ethnoburb, in which one ethnic minority group has a significant concentration, but does not necessarily comprise a majority, and analyzed the demographic profiles and socioeconomic characteristics of the Chinese population in Los Angeles to understand its role as a global economic outpost.
Abstract: This paper proposes a new model of ethnic settlement, the ethnoburb. Ethnoburbs are suburban ethnic clusters of residential areas and business districts in large American metropolitan areas. They are multi-ethnic communities, in which one ethnic minority group has a significant concentration, but does not necessarily comprise a majority. The paper operationalises the ethnoburb model via an analysis of the demographic profiles and socioeconomic characteristics of the ethnoburban Chinese population in Los Angeles in order to understand the ethnoburb's role as a global economic outpost. This analysis also highlights social stratification by country of origin, and the micro-geographies of neighbourhood and workplace, features which reveal the ethnoburb's character as an urban mosaic.

Journal ArticleDOI
TL;DR: In this article, strain gradient plasticity theory is used to model materials undergoing small-scale indentations, and a strong effect of including strain gradients in the constitutive description is found with hardness increasing by a factor of two or more over the relevant range of behavior.
Abstract: Indentation tests at scales on the order of one micron have shown that measured hardness increases significantly with decreasing indent size, a trend at odds with the size-independence implied by conventional plasticity theory. In this paper, strain gradient plasticity theory is used to model materials undergoing small-scale indentations. Finite element implementation of the theory as it pertains to indentation modeling is briefly reviewed. Results are presented for frictionless conical indentations. A strong effect of including strain gradients in the constitutive description is found with hardness increasing by a factor of two or more over the relevant range of behavior. The results are used to investigate the role of the two primary constitutive length parameters in the strain gradient theory. The study indicates that indentation may be the most effective test for measuring one of the length parameters.

Journal Article
TL;DR: A comparison of a traditional outreach intervention and an innovative social network model, termed "a peer-driven intervention" (PDI), suggests that given guidance and nominal incentives, IDUs can play a more extensive role in community outreach efforts than the traditional model allows.
Abstract: OBJECTIVE: Since 1985, community outreach efforts to combat acquired immunodeficiency syndrome (AIDS) among injecting drug users (IDUs) in the United States have overwhelmingly depended on a provider-client model that relies on staffs of professional outreach workers. We report on a comparison of this traditional outreach model with an innovative social network model, termed "a peer-driven intervention" (PDI). The latter provides IDUs with guidance and structured incentives that permit them to play a much more active role in the outreach process, thereby harnessing peer pressure on behalf of human immunodeficiency virus (HIV) prevention efforts. METHODS: We compare the performance of a traditional outreach intervention (TOI) and a PDI that were implemented in medium-sized towns in eastern and central Connecticut. Comparisons are based on the number and representativeness of IDUs recruited at each site, the effectiveness of HIV prevention education, compliance rates with AIDS risk reduction recommendations, and relative cost. The analyses are based on 522 initial interviews and 190 six-month follow-up interviews conducted during the first two years of each intervention's operation. RESULTS: Both interventions produced significant reductions in HIV risk behaviors, as measured using self-reports. The PDI outperformed the traditional intervention with respect to the number of IDUs recruited, the ethnic and geographic representativeness of the recruits, and the effectiveness of HIV prevention education. In addition, the costs of recruiting IDUs into the intervention and educating them about HIV in the community was only one-thirtieth as much in the PDI as in the traditional intervention. CONCLUSIONS: The findings suggest that given guidance and nominal incentives, IDUs can play a more extensive role in community outreach efforts than the traditional model allows. The findings also suggest that both interventions reduce HIV-associated risk behaviors, but the PDI reaches a larger and more diverse set of IDUs, and does so at much less expense.

Journal ArticleDOI
TL;DR: It is concluded that BMPs induce noggin transcription in Ob cells, a probable mechanism to limit BMP action in osteoblasts.
Abstract: Bone morphogenetic proteins (BMPs) induce the differentiation of cells of the osteoblastic lineage and enhance the function of the osteoblast. Growth factors are regulated by binding proteins, but there is no information about binding proteins for BMPs in skeletal cells. Noggin specifically binds BMPs, but its expression by cells of the osteoblastic lineage has not been reported. We tested for the expression of noggin and its induction by BMP-2 in cultures of osteoblast-enriched cells from 22-d-old fetal rat calvariae (Ob cells). BMP-2 caused a time- and dose-dependent increase in noggin mRNA and polypeptide levels, as determined by Northern and Western blot analyses. The effects of BMP-2 on noggin transcripts were dependent on protein, but independent of DNA synthesis. BMP-2 increased the rates of noggin transcription as determined by nuclear run-on assays. BMP-4, BMP-6, and TGF-beta1 increased noggin mRNA in Ob cells, but basic fibroblast growth factor, platelet- derived growth factor BB, and IGF-I did not. Noggin decreased the stimulatory effects of BMPs on DNA and collagen synthesis and alkaline phosphatase activity in Ob cells. In conclusion, BMPs induce noggin transcription in Ob cells, a probable mechanism to limit BMP action in osteoblasts.