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Similar Pathways (similar + pathway)
Selected AbstractsGoal Striving Within Agentic and Communal Roles: Separate but Functionally Similar Pathways to Enhanced Well-BeingJOURNAL OF PERSONALITY, Issue 3 2008Kennon M. Sheldon ABSTRACT Do agency and communion strivings provide functionally similar but predictively independent pathways to enhanced well-being? We tested this idea via a year-long study of 493 diverse community adults. Our process model, based on self-determination and motive disposition theories, fit the data well. First, the need for achievement predicted initial autonomous motivation for agentic (work and school) role-goals and the need for intimacy predicted felt autonomy for communal (relationship and parenting) goals. For both agentic and communal goals, autonomous motivation predicted corresponding initial expectancies that predicted later goal attainment. Finally, each type of attainment predicted improved adjustment or role-satisfaction over the year. Besides being similar across agency and communion, the model was also similar across race and gender, except that the beneficial effects of communal goal attainment were stronger for high need for intimacy women and Blacks. Implications for agency/communion theories, motivation theories, and theories of well-being are discussed. [source] Depositional environment of Sirius Group sediments, Table Mountain, Dry Valleys area, AntarcticaGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2002James R. Goff Outcrops and cores of the Sirius Group sediments were studied at Table Mountain, Dry Valleys area, Antarctica. These sediments form a surficial veneer at least 9.5 m thick. Three facies , a gravelly sandstone, a sandstone, and a sandy conglomerate , are mapped and described from 13 outcrops and three cores. The gravelly sandstone, constituting 13%of all cored material, is bimodal with matrix-supported clasts comprising 5,33%of the facies. Fabric analysis indicates that it was deposited primarily by lodgment from glacial ice but with minor elements of meltout and flow. The sandstone facies, constituting 77%of all cored material, is a well-sorted, fine- to medium-grained sand, which commonly has laminated bedding. It is predominantly a glaciofluvial deposit but has some glaciolacustrine elements. The sandy conglomerate, constituting 10%of all cored material, is a minor facies. It is massive and clast-supported. It was deposited in a high-energy environment suggestive of subglacial meltwater channels. Sirius Group sediments at Table Mountain are the result of wet-based ice advancing and retreating over waterlain deposits. This is consistent with an advancing ice mass in climatic conditions that were warmer than present. The majority of the sediments were deposited by alpine ice following a similar pathway to the present-day Ferrar Glacier and as such the depositional environment is one that concurs with evidence of a stable East Antarctic Ice Sheet approach. At Table Mountain, the predominantly glaciofluvial and glaciolacustrine facies is inferred to represent a more distal part of the Sirius Group environment than that seen at other outcrops in the Dry Valleys. [source] Poly(propylene carbonate), old CO2 Copolymer with New AttractivenessMACROMOLECULAR SYMPOSIA, Issue 1 2007Gerrit A. Luinstra Abstract Summary: The catalytic synthesis of poly(propylene carbonate) (PPC) from propylene oxide and CO2 is mediated by zinc glutarate and chromium salen complexes. The determined solid state structure of the zinc glutarate was taken to model the polymerisation of ethylene oxide. It has a low activation energy for a reaction path involving two zinc atoms, where one binds the nucleophilic alkoxy chain end and one activates the epoxide. A similar pathway may operate in the alternating copolymerization PO/CO2 as is shown in the homogeneous chromium salen catalyst system. The material profile was determined of PPC with 93% carbonate linkages. A study of the transparent blend with poly(lactic acid) (PLA) shows that the polymers are not miscible, but rather compatible as they are finely dispersed and show linear behaviour in the mechanic properties. The permeability of oxygen, carbon dioxide and water of the composite PPC/PLA are also reported. [source] A longitudinal study of cannabis use and mental health from adolescence to early adulthoodADDICTION, Issue 4 2000Rob McGee Aims. To examine the longitudinal association between cannabis use and mental health. Design. Information concerning cannabis use and mental health from 15 to 21 years was available for a large sample of individuals as part of a longitudinal study from childhood to adulthood. Participants. Participants were enrolled in the Dunedin Multidisciplinary Health and Development Study, a research programme on the health, development and behaviour of a large group of New Zealanders born between 1 April 1972 and 31 March 1973. Measurements. Cannabis use and identification of mental disorder was based upon self-report as part of a general assessment of mental health using a standard diagnostic interview. Daily smoking and alcohol use at age 15 were assessed by self-report. Indices of family socio-economic status, family climate and parent - child interaction were formed using information gathered from parent report and behavioural observations over early childhood. Childhood behaviour problems were assessed by parent and teacher report. Attachment to parents was assessed in adolescence. Findings. Cross-sectional associations between cannabis use and mental disorder were significant at all three ages. Both outcome variables shared similar pathways of low socio-economic status and history of behaviour problems in childhood, and low parental attachment in adolescence. Mental disorder at age 15 led to a small but significantly elevated risk of cannabis use at age 18; by contrast, cannabis use at age 18 elevated the risk of mental disorder at age 21. The latter association reflected the extent to which cannabis dependence and other externalizing disorders at age 21 were predicted by earlier level of involvement with cannabis. Conclusions. The findings suggest that the primary causal direction leads from mental disorder to cannabis use among adolescents and the reverse in early adulthood. Both alcohol use and cigarette smoking had independent associations with later mental health disorder. [source] Suicide without explicit precursors: a state of secret despair?JOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 3 2004David Canter Abstract Although it is usually assumed that all those who commit suicide give some prior indication of their intention to take their own life, there is growing evidence that a small but significant proportion of suicides occur without any clear, explicit indicators. It is proposed that these suicides share similar pathways to other suicides but that the despair involved is not expressed so clearly, often being kept secret. In order to identify such suicides and potential suicides it is helpful to have an indicator of the dominant sub-sets of constituents that are precursors to suicide. A 14-item Suicide Precursors Scale (SPS) was therefore developed. This was applied to 128 cases of suicide that occurred between January 1997 and December 2000 in Stockport (South Manchester, UK). A very high alpha coefficient of 0.98 supported the reliability and homogeneity of the SPS. A Multi-Dimensional Scaling (MDS) analysis of the SPS revealed three prototypical sub-sets of expressions of suicidal actions,illness, life circumstances, and depressive history. These are offered as coherent themes in the life of potential suicides, which may be of assistance both in determining whether an equivocal death is suicide or not, and in alerting caring agencies to the potential for suicide even when the despair is kept secret. Copyright © 2004 John Wiley & Sons, Ltd. [source] Spontaneous Redox Reactions of Dopaquinone and the Balance between the Eumelanic and Phaeomelanic PathwaysPIGMENT CELL & MELANOMA RESEARCH, Issue 4 2000E.J. LAND Eumelanogenesis and phaeomelanogenesis diverge at an early stage in pigment formation, namely at the point where dopaquinone, the initial product of tyrosine oxidation by tyrosinase, undergoes one of two types of reaction: either (1) a reductive endocyclisation in which a Michael addition of the side-chain amino group takes place; or (2) a reductive addition of cysteine to give cysteinyldopa. In the former case, the product cyclodopa, is known rapidly to undergo a redox exchange reaction with dopaquinone to yield dopachrome, the precursor of the eumelanogenic pathway. In the second instance, cysteinyldopa is regarded as leading to the formation of benzothiazoles, which are characteristic of phaeomelanin. The precursor molecule of the phaeomelanic pathway is cysteinyldopaquinone. We have examined quantitatively the role of dopaquinone in the non-enzymatic oxidation of 5-S-cysteinyldopa using pulse radiolysis and have demonstrated that the redox exchange reaction between dopaquinone and 5-S-cysteinyldopa occurs spontaneously with a rate constant of 8.8×105 M,1 sec,1. This study has also enabled an improved estimate of ,4×107 M,1sec,1 to be obtained for the rate constant of the reaction of dopaquinone with cyclodopa. Calculations utilising these figures and estimates of the rate constants for the other reactions in early melanogenesis, demonstrate that, whilst similar pathways are invoked, the phaeomelanic pathway predominates in the presence of cysteine, irrespective of the availability of dopaquinone and thus independently of the rate of tyrosinase-catalysed oxidation. This suggests that the balance between the formation of eumelanin and phaeomelanin is regulated principally by the availability of cysteine at the site of melanogenesis. [source] Change of the unbinding mechanism upon a mutation: A molecular dynamics study of an antibody,hapten complexPROTEIN SCIENCE, Issue 10 2005Raffaele Curcio Abstract We study forced unbinding of fluorescein from the wild type (WT) and a mutant [H(H58)A] of the single-chain variable-fragment (scFv) anti-fluorescein antibody FITC-E2 by molecular dynamics simulations using various pulling techniques. A large number of long simulations were needed to obtain statistically meaningful results as both the wild type and the H(H58)A mutant unbinding occurs through multiple pathways, often with metastable intermediates. For the wild type, the rate-limiting step in the unbinding process corresponds to the breaking of the non-native interactions characteristic of a specific intermediate. The H(H58)A mutation disfavors the occurrence of this intermediate. Two events where the hapten partially unbinds in the absence of pulling force are observed in extensive equilibrium simulations of the wild type, and their analysis indicates that forced unbinding and spontaneous unbinding proceed along similar pathways. The different unbinding mechanisms observed in the simulations suggest a possible reason for the difference in the experimental off-rate between the two antibodies. We predict mutations that are expected to modulate the occurrence of the unbinding intermediate. For two such new mutants [H(H58)A and S(H52)A], our predictions are validated in silico by additional simulations. The accompanying paper in this issue by Honegger et al. reports the X-ray structure of FITC-E2 with a derivative of fluorescein, which was used as the starting conformation for the work presented here. [source] Mechanisms of stretch-induced muscle damage in normal and dystrophic muscle: role of ionic changesTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005D. G. Allen Muscle damage, characterized by prolonged weakness and delayed onset of stiffness and soreness, is common following contractions in which the muscles are stretched. Stretch-induced damage of this sort is more pronounced in the muscular dystrophies and the profound muscle damage observed in these conditions may involve similar pathways. It has been known for many years that damaged muscles accumulate calcium and that elevating calcium in normal muscles simulates many aspects of muscle damage. The changes in intracellular calcium, sodium and pH following stretched contractions are reviewed and the various pathways which have been proposed to allow ion entry are discussed. One possibility is that TRPC1 (transient receptor potential, canonical), a protein which seems to form both a stretch-activated channel and a store-operated channel, is the main source of Ca2+ entry. The mechanisms by which the changes in intracellular ions contribute to reduced force production, to increased protein breakdown and to increased membrane permeability are considered. A hypothetical scheme for muscle damage which incorporates these ideas is presented. [source] | |||||||||||||