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Articles de revues sur le sujet "Biological first-degree relative"
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Saito, Toshikazu, Yoshinari Katamura, Hiroki Ozawa, Shinichi Hatta et Naohiko Takahata. « Platelet GTP-binding protein in long-term abstinent alcoholics with an alcoholic first-degree relative ». Biological Psychiatry 36, no 7 (octobre 1994) : 495–97. http://dx.doi.org/10.1016/0006-3223(94)90650-5.
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SOBCZAK, S., W. J. RIEDEL, I. BOOIJ, M. AAN HET ROT, N. E. P. DEUTZ et A. HONIG. « Cognition following acute tryptophan depletion : difference between first-degree relatives of bipolar disorder patients and matched healthy control volunteers ». Psychological Medicine 32, no 3 (avril 2002) : 503–15. http://dx.doi.org/10.1017/s0033291702005342.
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Background. Serotonergic circuits have been proposed to mediate cognitive processes, particularly learning and memory. Cognitive impairment is often seen in bipolar disorders in relation to a possible lowered serotonergic turnover.Methods. We investigated the effects of acute tryptophan depletion (ATD) on cognitive performance in healthy first-degree relatives of bipolar patients (FH) (N = 30) and matched controls (N = 15) in a placebo-controlled, double-blind cross-over design. Performance on planning, memory and attention tasks were assessed at baseline and 5 h after ATD.Results. Following ATD, speed of information processing on the planning task was impaired in the FH group but not in the control group. FH subjects with a bipolar disorder type I relative (FH I) showed impairments in planning and memory, independent of ATD. In all subjects, ATD impaired long-term memory performance and speed of information processing. ATD did not affect short-term memory and focused and divided attention.Conclusions. The results suggest serotonergic vulnerability affecting frontal lobe areas in FH subjects, indicated by impaired planning. Biological vulnerability in FH I subjects is reflected in impaired planning and memory performance. In conclusion, the cognitive dysfunctions in FH subjects indicate an endophenotype constituting a possible biological marker in bipolar psychopathology. Serotonin appears to be involved in speed of information processing, verbal and visual memory and learning processes.
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Raygoza Garay, J., W. Turpin, M. Smith, A. Goethel, D. S. Guttman et K. Croitoru. « A17 ASSOCIATION BETWEEN HOST INFLAMMATION-RELATED PROTEOMICS AND GUT MICROBIOME IN HEALTHY FIRST-DEGREE RELATIVES OF CROHN’S DISEASE PATIENTS ». Journal of the Canadian Association of Gastroenterology 3, Supplement_1 (février 2020) : 20–21. http://dx.doi.org/10.1093/jcag/gwz047.016.
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Abstract Background Crohn’s disease (CD) is a chronic inflammatory condition of the gastrointestinal tract. It has been suggested that the cause of CD is due to microbial and environmental factors that induce an imbalance of the immune system in genetically susceptible individuals. The Genetic Environmental Microbial (GEM) Project is a prospective study of asymptomatic first-degree relatives (FDR) of CD patients, recruited to understand the biological and environmental determinants of disease development. Aims Here, we aim to define the relationships between the host inflammation-related proteomics and gut microbiome composition in a cohort of 320 healthy CD FDRs at the time of recruitment. Methods We measured 92 inflammation-related serum proteins using the Olink® ’Inflammation’ proteomics panel. Stool microbial composition was determined by sequencing the V4 region of the 16S rRNA. To assess the relationship between serum protein levels and the relative abundance of microbial taxa, we used a zero-inflated two-part regression model corrected for multiple-comparisons (significant association at p< 2.75 × 10–4). Results We found fifteen serum proteins that were each significantly associated with the relative abundances of one to five genera or families, depending on the analyte. Of particular interest to CD, the relative abundance of both TNF-β and LIGHT (TNFSF14) were negatively associated with the relative abundance of bacteria in the Parabacteroides genus. Both TNF-β and LIGHT are members of the Tumor Necrosis Factor (TNF) family of cytokines with roles in mucosal healing, IgA production, and in control of innate lymphoid cells (ILCs). These processes have been hypothesized to have critical roles in CD pathology. Interestingly, prior work also demonstrates that Parabacteroides distasonis enhanced colitis in a mouse model and was isolated from a gut wall-cavitating microlesion in a patient with severe CD. Other inflammation-related proteins with significant taxa associations include IL-2, IL-33, OSM, 4E_BP1, IL-1α, ARTN, AXIN1, and CDCP1. Conclusions This study highlights the associations between inflammation associated proteomics and gut microbial taxa in asymptomatic FDRs of CD patients. The mechanisms explaining this association will require further analysis. Funding Agencies CCC The Leona M. and Harry B. Helmsley Charitable Trust
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Temgoua, Mazou Ngou, Gloria Ashuntantang, Marie José Essi, Joël Nouktadie Tochie, Moussa Oumarou, Acho Fon Abongwa, Aimé Mbonda et Samuel Kingue. « Prevalence and Risk Factors for Chronic Kidney Disease in Family Relatives of a Cameroonian Population of Hemodialysis Patients : A CrossSectional Study ». Hospital Practices and Research 4, no 1 (26 janvier 2019) : 12–17. http://dx.doi.org/10.15171/hpr.2019.02.
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Background: In sub-Saharan Africa (SSA), the trend in the number of patients admitted for maintenance hemodialysis is on the rise. The identification of risk factors for chronic kidney disease (CKD) ensures adequate primary and secondary preventive measures geared at reducing the burden of CKD in low-resource settings. A family history of CKD is an established risk factor for CKD in high-income countries. However, data on family predisposition to CKD is scarce in the literature on SSA. Objective: The current study aimed to determine the prevalence and risk factors of CKD in family relatives of a Cameroonian population of hemodialysis patients (HDP) followed-up in a major hemodialysis referral center in Cameroon. Methods: The current cross-sectional study was conducted over four months on a consecutive sample of first-degree family relatives of end-stage renal disease patients undergoing maintenance hemodialysis at the hemodialysis unit of the General Hospital of Yaoundé. For each participating family relative, socio-demographic characteristics, clinical data, and biological data including fasting blood glucose, proteinuria, and serum creatinine were collected. Results: A total of 82 first-degree family relatives of HDP were recruited. The prevalence of CKD among the participants was 15.8%. The main identified risk factors for CKD were age (P = 0.0015), female gender (P = 0.0357), hypertension (P = 0.0004), regular intake of herbal remedies (P = 0.0214), and diabetes mellitus (P = 0.0019). Conclusion: Overall, the current findings suggest an urgent need for population education, routine screening of CKD, and the identification of risk factors in first-degree family relatives of HDP in Cameroon.
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Saloua, Bentaibi, Rahou Abdelilah, Chillasse Lahsen, Hammada Soumaya et Abba Elhassan. « Evaluation of Biological Water Quality by Biological Macrophytic Index in River : Application on the Watershed of Beht River ». European Scientific Journal, ESJ 13, no 27 (30 septembre 2017) : 217. http://dx.doi.org/10.19044/esj.2017.v13n27p217.
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The Biological macrophytic Index for River (IBMR) is based on the examination of aquatic plants (macrophytes) to determine the river quality, particularly its degree of eutrophication linked to nitrogen content and phosphorus in water . The aim of this study was to evaluate the biological quality of a Moroccan river through the IBMR in view to integrate it into the monitoring programs of water quality. Indeed, this method of assessment of biological water quality is under development and adaptation to the Moroccan hydro-biological context. Beht River on which we selected 13 stations, the quality was evaluated during a first sampling campaign in 2014. The results show a good representation of the trophic status of stations relative to environmental conditions of the environment such as the types of wastes, agricultural and other activities. Indeed, the stations with a strong trophic level often come downstream urban areas or near farms. The low average index values correspond to stations with little to very little polluting activities.
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Scheftner, William A., Michael A. Young, Jean Endicott, William Coryell, Louis Fogg, David C. Clark et Jan Fawcett. « Family History and Five-year Suicide Risk ». British Journal of Psychiatry 153, no 6 (décembre 1988) : 805–9. http://dx.doi.org/10.1192/bjp.153.6.805.
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Family history was examined to determine whether suicide in index patients is associated with suicidal behaviour or mental disorder in their first-degree relatives. Twenty-seven suicides occurred within 5½ years among 955 affectively disordered probands. Among 5042 proband relatives aged 18 years and older, 44 had committed suicide prior to proband entry to the study; however, only one was the relative of a proband suicide. Only two of the relatives who committed suicide were themselves related. As to attempted suicide of relatives, neither the number of attempts nor the severity of attempt was predictive of suicide in probands. Comparison of diagnosis between groups of relatives showed more drug abuse among relatives of proband suicides; this appears to be related to drug abuse among the proband suicides themselves. In contrast to the clustering of suicides within biological families found in other research, these data do not support the use of family history as a clinically useful indicator of suicidal potential in affectively disordered probands.
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Eriksson, Hanna, Karin Wirdefeldt, Signild Åsberg et Johan Zelano. « Family history increases the risk of late seizures after stroke ». Neurology 93, no 21 (23 octobre 2019) : e1964-e1970. http://dx.doi.org/10.1212/wnl.0000000000008522.
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ObjectiveTo assess the association between a family history of epilepsy and risk of late poststroke seizures (LPS).MethodsThis register-based cohort study was based on adult patients from the Swedish Stroke Register (Riksstroke) with stroke from 2001 to 2012 and no prior epilepsy. LPS (>7 days after stroke) and epilepsy were ascertained in cases and in their first-degree biological relatives by cross-referencing Riksstroke, the Multi-Generation Register, and the National Patient Register.ResultsOf 86,550 patients with stroke, a family history of epilepsy was detected in 7,433 (8.6%), and LPS (>7 days after stroke) occurred in 7,307 (8.4%). The survival-adjusted risk of LPS was higher in patients with compared to those without a family history of epilepsy: 6.8% (95% confidence interval [CI] 6.2%–7.4%) vs 5.9% (95% CI 5.7%–6.1%) at 2 years and 9.5% (95% CI 8.7%–10.3%) vs 8.2% (95% CI 8.0%–8.4%) at 5 years. In a Cox model adjusted for age, sex, and stroke type, the hazard ratio (HR) for LPS in patients with stroke with ≥1 relative with epilepsy was 1.18 (95% CI 1.09–1.28). The increased HR remained significant with adjustments for stroke severity and in multiple sensitivity analyses. A higher risk for patients with stroke with >1 relative with epilepsy was also seen but was not significant in all Cox models.ConclusionsAlthough stroke characteristics remain the most important risk factors for LPS, having a first-degree relative with epilepsy also increases the risk in a multivariate analysis. The findings highlight the need for family history assessment in patients with stroke and the need for future studies on genetic vulnerability and environmental factors that may aid in the identification of at-risk individuals.
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González Muñoza, C., M. Calafat, J. P. Gisbert, E. Iglesias, M. Minguez, B. Sicilia, M. Esteve et al. « P654 Clinical outcomes in familial versus sporadic inflammatory bowel disease diagnosed in the era of biological therapies. Prospective data from the ENEIDA registry ». Journal of Crohn's and Colitis 16, Supplement_1 (1 janvier 2022) : i567. http://dx.doi.org/10.1093/ecco-jcc/jjab232.775.
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Abstract Background It has been reported that familial aggregation occurs in 10–20% of inflammatory bowel disease (IBD) patients1. Familial IBD has been associated with disease anticipation2 and with an increased need for immunosuppressants3 and surgery4. However, most studies were performed before the widespread use of biological agents and this may impact on the need for surgery. We aimed to compare the clinical outcomes of IBD (by means of the need for biological therapy and abdominal surgery) between familial and sporadic forms of IBD in the era of biological therapies. Methods Data were extracted from the ENEIDA registry by GETECCU, a Spanish, prospectively-maintained, IBD database in which more than 80 centers are participating. Only adult patients diagnosed with IBD since 2005 and prospectively followed in the registry since diagnosis were included. Familial IBD was defined as those cases with at least one first-degree relative diagnosed with IBD. Sporadic IBD was defined as those cases with no familial relative (of any degree) with IBD. Kaplan-Meier survival curves were performed to evaluate the cumulative probabilities of remaining biologic-free and surgery-free. Log-rank test was performed to compare them between familial and sporadic IBD forms. Chi-square test was performed for the rest of variables. Results A total of 5,263 patients (2,627 Crohn’s disease [CD]; 2,636 ulcerative colitis [UC]) were included. Of them, 507 (10%) were familial cases (274 CD, 233 UC; P=0.05). The median follow-up was 38,4 and 35.5 months, respectively (P=0.086). Familial cases were younger (P=0.022) and had a higher proportion of females among UC cases (P=0.048). No differences were observed in the need for biological therapy in both CD and UC between familial and sporadic IBD. Regarding surgery, no differences were observed in the cumulative probabilities of a first intestinal resection for CD and colectomy for UC. Similar results were obtained when all the analyses were restricted to those subgroups at high-risk for surgery (i.e. CD with ileal involvement and extensive UC). Conclusion In patients diagnosed with IBD in the era of biological therapies, familial forms have the same requirements for biological agents and resectional surgery as sporadic forms. Therefore, familial aggregation does not seem to be a factor for a more aggressive disease.
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Devkota, Bishnu P., et E. Armbrecht. « Two years' observational study of racial difference of breast cancer in patients presenting to a tertiary care hospital serving indigent population ». Health Renaissance 11, no 2 (19 juin 2013) : 102–6. http://dx.doi.org/10.3126/hren.v11i2.8215.
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Background: Breast cancer is the most common malignancy after non-melanoma skin cancers and second highest cause of cancer deaths (after lung cancer) in females. Objective: To assess racial difference of breast cancer in patients presenting to a tertiary care hospital serving indigent population. Methods: Medical records of 119 Caucasians and 146 African American women with pathologically proven breast cancer who were admitted in a tertiary care hospital serving the indigent population from January 2004 to December 2006 were reviewed retrospectively. Analysis of Variance was performed for within and between group differences using SPSS 19. Results: Our study showed that mean age of cancer diagnosis was much earlier (47.6 years) in white women whose second degree relatives have breast cancer than those women whose first degree relatives have breast cancer (58.6 years). However, in the black women this differencewas not observed (p value for white is 0.002 but for black it was 0 .94). Conclusion: Family history of women with breast cancer in this study showed history of breast cancer in a second degree female relative increased the risk of breast cancer in white women; positive history was associated with earlier age of onset of the disease. We suggest future studies should look into genetic and biological markers in the second generation family members for increased risk of breast cancer. Health Renaissance, January-April 2013; Vol. 11 No.1; 102-106 DOI: http://dx.doi.org/10.3126/hren.v11i2.8215
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Miklowitz, David J., et Kiki D. Chang. « Prevention of bipolar disorder in at-risk children : Theoretical assumptions and empirical foundations ». Development and Psychopathology 20, no 3 (2008) : 881–97. http://dx.doi.org/10.1017/s0954579408000424.
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AbstractThis article examines how bipolar symptoms emerge during development, and the potential role of psychosocial and pharmacological interventions in the prevention of the onset of the disorder. Early signs of bipolarity can be observed among children of bipolar parents and often take the form of subsyndromal presentations (e.g., mood lability, episodic elation or irritability, depression, inattention, and psychosocial impairment). However, many of these early presentations are diagnostically nonspecific. The few studies that have followed at-risk youth into adulthood find developmental discontinuities from childhood to adulthood. Biological markers (e.g., amygdalar volume) may ultimately increase our accuracy in identifying children who later develop bipolar I disorder, but few such markers have been identified. Stress, in the form of childhood adversity or highly conflictual families, is not a diagnostically specific causal agent but does place genetically and biologically vulnerable individuals at risk for a more pernicious course of illness. A preventative family-focused treatment for children with (a) at least one first-degree relative with bipolar disorder and (b) subsyndromal signs of bipolar disorder is described. This model attempts to address the multiple interactions of psychosocial and biological risk factors in the onset and course of bipolar disorder.
Livres sur le sujet "Biological first-degree relative"
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Longuenesse, Béatrice. The First Person in Cognition and Morality. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198845829.001.0001.
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The book is the revised version of two lectures presented, in the spring 2017, as the Spinoza lectures in the University of Amsterdam. Both lectures explore the contrast and collaboration between two types of standpoint on the world, each of which finds expression in a specific use of the first-person pronoun “I.” One standpoint is the particular standpoint we have on the world insofar as we are spatially and temporally located, biologically unique, socially and culturally determined individuals. The other is the universally communicable standpoint we share or can hope to share with all other human beings, whatever their particular biological, social, or cultural determination. The book explores the degree to which using the first-person pronoun “I” is the expression of one or the other standpoint. The first lecture explores this question in relation to the exercise of our mental capacities in abstract reasoning and knowledge of objective facts about the world. The second lecture explores this question in relation to what we take to be our moral obligations.
Chapitres de livres sur le sujet "Biological first-degree relative"
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Deslauriers, Marguerite. « The Relation between Biological and Political Sexual Differences ». Dans Aristotle on Sexual Difference, 207–56. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780197606186.003.0005.
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Chapter Four, “The Relation between Biological and Political Sexual Differences” considers the relation between sexual difference as it manifests in male and female bodies and in the deliberative capacities of men and women. It explores two paths to establish a causal connection between the physiology of the sexes and their psychology, in particular their different moral and deliberative capacities. The first moves from the colder temperature of the female body, to compromised sensory capacities, to a defective deliberative capacity. The second moves from the colder temperature of the female to a lower degree of thumos (“spirit”), to an incapacity for rule. In this chapter I argue that the second path is better, for two reasons: first, it explains the particular defect that Aristotle attributes to women, and second, it allows us to distinguish the imperfection of women from the imperfection of natural slaves.
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Lewis, William M. « The Cast of Characters ». Dans Wetlands Explained. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195131833.003.0008.
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Through the inexorable workings of natural selection, wetlands have come to support a group of species that are especially well adapted to the physical and chemical peculiarities of saturated substrates and shallow water. These species give wetlands their distinctive biological signature and sustain the biotic functions of wetlands (Tiner 1998). The species that occupy wetlands show varying degrees of specialization. Some are so highly specialized that they can live or reproduce only in wetlands; these are called obligate wetland species. A second group contains organisms that are adapted for life in wetlands but are not restricted to wetlands; these are called facultative wetland species. Facultative wetland species show every conceivable shade of association with wetlands: they range from almost obligate to barely facultative. The distribution of obligate wetland species coincides closely with the distribution of wetlands. Thus, one could be tempted to rely heavily on obligate wetland species to find and map wetlands. Inference from obligate wetland species, however, must be tempered with caution. First, the absence of obligate wetland species does not necessarily mean absence of wetland, given that a wetland can be mostly or even entirely occupied by facultative wetland species. In addition, the degree to which a given species is a wetland obligate may not be known with absolute certainty. Where a genetic variant or an unusual set of physical conditions prevails, a species that seemed to be obligate in other situations may prove to be merely facultative and thus not diagnostic proof of the presence of wetland. The perils of absolute reliance on obligate wetland species have turned the attention of wetland mappers to the analysis of entire communities. Although community analysis can be done in a number of ways, the central idea is to score a community according to the proportionate representation of species that show a known facultative or obligate affinity with wetland conditions. The analysis of communities for the purpose of mapping and identifying wetlands has been focused almost entirely on vascular plants (grasses, forbs, shrubs, and trees). Two good reasons for this are the relative ease with which plant communities can be analyzed and the immobility of plants.
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Van Genuchten, M. Th, et E. A. Sudicky. « Recent Advances in Vadose Zone Flow and Transport Modeling ». Dans Vadose Zone Hydrology. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195109900.003.0010.
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The fate and transport of a variety of chemicals migrating from industrial and municipal waste disposal sites, or applied to agricultural lands, is increasingly becoming a concern. Once released into the subsurface, these chemicals arc subject to a large number of simultaneous physical, chemical, and biological processes, including sorption-desorption, volatilization, and degradation. Depending upon the type of organic chemical involved, transport may also be subject to multiphase flow that involves partitioning of the chemical between different fluid phases. Many models of varying degree of complexity and dimensionality have been developed during the past several decades to quantify the basic physicochemical processes affecting transport in the unsaturated zone. Models for variably saturated water flow, solute transport, aqueous chemistry, and cation exchange were initially developed mostly independently of each other, and only recently has there been a significant effort to couple the different processes involved. Also, most solute transport models in the past considered only one solute. For example, the processes of adsorption- desorption and cation exchange were often accounted for by using relatively simple linear or nonlinear Freundlich isotherms such that all reactions between the solid and liquid phases were forced to be lumped into a single distribution coefficient, and possibly a nonlinear exponent. Other processes such as precipitation-dissolution, biodegradation, volatilization, or radioactive decay were generally simulated by means of simple first- and/or zero-order rate processes. These simplifying approaches were needed to keep the mathematics relatively simple in view of the limitations of previously available computers. The problem of coupling models for water flow and solute transport with multicomponent chemical equilibrium and nonequilibrium models is now increasingly being addressed, facilitated by the introduction of more powerful computers, development of more advanced numerical techniques, and improved understanding of the underlying transport processes. One major frustrating issue facing soil scientists and hydrologists in dealing with the unsaturated zone, both in terms of modeling and experimentation, is the overwhelming heterogeneity of the subsurface environment.
Actes de conférences sur le sujet "Biological first-degree relative"
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Layton, Astrid, John Reap et Bert Bras. « A Correlation Between Thermal Efficiency and Biological Network Cyclicity ». Dans ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/es2011-54787.
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This article investigates a correlation between the thermal efficiency of ideal power cycles and a structural measure of the degree of interactions in networks known as cyclicity. Efficient design of networks that reuse materials and energy motivates the work. Corporate “take-back” plans, multi-company industrial symbioses and public recycling programs recover products, components and materials using partially closed loop networks. As resources become scarcer and more expensive, the prevalence of these networks is likely to increase, and the importance of designing efficient networks grows. Multiple structural and material flow metrics that one might use to aid network design exist. One novel approach to network design involves patterning industrial networks on ecological ones. This latter idea lays at the heart of industrial symbiosis efforts. However, neither the materials metric approach nor the bioinspired ecological patterns approach stands upon a strong theoretical base. As a test of both approaches, this work uses a structural cycling metric, cyclicity, previously used to quantify patterns in ecosystems, to quantify energy flow in ideal thermodynamic cycles. The objective is not to learn about thermodynamic cycles. Rather, the intent of the comparison is to reveal whether trends in network structure as given by cyclicity relate to the fundamental laws of thermodynamics. Familiar ideal power cycles are first redrawn as energy flow networks. Cyclicity values are then calculated for these networks. A comparison shows that thermal efficiency increases with increasing cyclicity for fixed source and sink temperatures within a cycle. This results from the practice of adding cyclical energy paths (i.e. a regenerator) to an ideal power cycle, to increase thermal efficiency. The remainder of the article comments on the potential ramifications of this finding for the design of cycling industrial networks.
Rapports d'organisations sur le sujet "Biological first-degree relative"
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Levisohn, Sharon, Maricarmen Garcia, David Yogev et Stanley Kleven. Targeted Molecular Typing of Pathogenic Avian Mycoplasmas. United States Department of Agriculture, janvier 2006. http://dx.doi.org/10.32747/2006.7695853.bard.
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Intraspecies identification (DNA "fingerprinting") of pathogenic avian mycoplasmas is a powerful tool for epidemiological studies and monitoring strain identity. However the only widely method available for Mycoplasma gallisepticum (MG) and M. synoviae (MS)wasrandom amplified polymorphic DNA (RAPD). This project aimed to develop alternative and supplementary typing methods that will overcome the major constraints of RAPD, such as the need for isolation of the organism in pure culture and the lack of reproducibility intrinsic in the method. Our strategy focussed on recognition of molecular markers enabling identification of MG and MS vaccine strains and, by extension, pathogenic potential of field isolates. Our first aim was to develop PCR-based systems which will allow amplification of specific targeted genes directly from clinical material. For this purpose we evaluated the degree of intraspecies heterogeneity in genes encoding variable surface antigens uniquely found in MG all of which are putative pathogenicity factors. Phylogenic analysis of targeted sequences of selected genes (pvpA, gapA, mgc2, and lp) was employed to determine the relationship among MG strains.. This method, designated gene targeted sequencing (GTS), was successfully employed to identify strains and to establish epidemiologically-linked strain clusters. Diagnostic PCR tests were designed and validated for each of the target genes, allowing amplification of specific nucleotide sequences from clinical samples. An mgc2-PCR-RFLP test was designed for rapid differential diagnosis of MG vaccine strains in Israel. Addressing other project goals, we used transposon mutagenesis and in vivo and in vitro models for pathogenicity to correlated specific changes in target genes with biological properties that may impact the course of infection. An innovative method for specific detection and typing of MS strains was based on the hemagglutinin-encoding gene vlhA, uniquely found in this species. In parallel, we evaluated the application of amplified fragment length polymorphism (AFLP) in avian mycoplasmas. AFLP is a highly discriminatory method that scans the entire genome using infrequent restriction site PCR. As a first step the method was found to be highly correlated with other DNA typing methods for MG species and strain differentiation. The method is highly reproducible and relatively rapid, although it is necessary to isolate the strain to be tested. Both AFLP and GTS are readily to amenable to computer-assisted analysis of similarity and construction of a data-base resource. The availability of improved and diverse tools will help realize the full potential of molecular typing of avian mycoplasmas as an integral and essential part of mycoplasma control programs.