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At least 415 records · Page 23Linked to original sources
PubMed2006

LNG decision making approaches compared.

Hazard zones associated with LNG handling activities have been a major point of contention in recent terminal development applications. Debate has reflected primarily worst case scenarios and discussion of these. This paper presents results from a maximum credible event approach. A comparison of results from several models either run by the authors or reported in the literature is presented. While larger scale experimental trials will be necessary to reduce the uncertainty, in the interim a set of base cases are suggested covering both existing trials and credible and worst case events is proposed. This can assist users to assess the degree of conservatism present in quoted modeling approaches and model selections.

Decision Making↗
PubMed2004

Functional liver recovery parallels autologous gut salvage in short bowel syndrome.

BACKGROUND/PURPOSE: Parenteral nutrition (PN) is life saving in short bowel syndrome. However, long-term parenteral nutrition is frequently complicated by a syndrome of progressive cholestatic liver disease that is considered to be irreversible beyond the early stages of cholestasis, particularly in the presence of any degree of fibrosis in the liver. The purpose of this study was to examine apparent improvement in PN-associated liver dysfunction in a cohort of children with short bowel syndrome. METHODS: A retrospective case-record review of all patients managed within a dedicated Intestinal Rehabilitation Program (IRP) identified 13 patients with short bowel who had PN-associated liver dysfunction, defined for this purpose as hyperbilirubinemia or an abnormal liver biopsy. RESULTS: At referral, 12 of the 13 patients were exclusively on PN, and one was on 50% PN. At current follow-up, 3 patients have achieved complete enteral autonomy from PN, and 7 patients have had smaller decrements in PN requirements. Specific operative procedures to improve intestinal function were undertaken in 11 patients; 4 patients also underwent cholecystectomies with biliary irrigation at the time of intestinal reconstruction. The median highest bilirubin level in these 13 patients was 10.7 mg% (range, 3.2 to 24.5 mg%). Liver biopsy results indicated that 5 patients were cirrhotic, 3 had bridging fibrosis, and 4 had severe cholestasis or lesser degrees of fibrosis. Of 10 survivors in this series, 9 patients currently have a serum bilirubin less than 1 mg% with a median bilirubin in the group of 0.6 mg% (range, 0.3 to 6.4 mg%). Twelve of the 13 patients in this series were initially referred for liver-small bowel transplantation. CONCLUSIONS: This preliminary experience suggests that PN-dependent patients with advanced liver dysfunction in the setting of the short bowel syndrome may, in some instances, experience functional and biochemical liver recovery. The latter appears to parallel autologous gut salvage in most cases. As a corollary, the authors believe that even advanced degrees of liver dysfunction should not preclude attempts at autologous gut salvage in very carefully selected patients. Such a policy of "aggressive conservatism" may help avoid the need for liver/intestinal transplantation in some patients who appear to be not responding to PN.

Adolescent↗
PubMed2005

Characteristics of HIV-1 env V3 loop sequences for subtype A1 variant spread in Eastern Europe.

OBJECTIVES: The aim of our investigation was to study the HIV-1 env V3 loop sequences of the subtype A variant of the virus actively circulating in the territory of Eastern Europe (A1-EE). DESIGN: It appears that the characteristics of HIV-1 V3 loop sequences of the thoroughly studied subtype B strains determine the viruses tropism and phenotype. We were interested to find out to what extent these trends are preserved with the subtype A isolates spread in Eastern Europe. METHODS: About 474 HIV-1 strains were isolated by cocultivation with phytohemagglutinin stimulated and interleukin-2 activated PBMC. Isolates were subtyped after distinct regions gag, pol and env were amplified by nested polymerase chain reaction. V3 sequences were studied in detail and compared with the isolates that appeared as SI or NSI in test-cultures MT-2. RESULTS: The subtype A HIV-1 strains spread in Eastern Europe appeared to have V3 loop sequences with a high level of conservatism. The consensus sequences of the SI and NSI isolates proved identical, and correspond to the phenotype markers of subtype B NSI strains. Nevertheless, the subtype A SI isolates induced active syncytium-formation processes in the MT-2 test culture. CONCLUSION: The data obtained evidenced to the following: the HIV-1 subtype A variant spread in Eastern Europe, is capable of using for interaction with receptor structures of sensitive cells the tools and mechanisms, which are significantly different from those described for subtype B.

Amino Acid Motifs↗
PubMed2006

Treatment preference patterns during a videotape decision aid for benign prostatic hyperplasia (BPH).

OBJECTIVE: As part of a study of men's responses to a videotape decision aid [Rovner DR, Wills CE, Bonham V, Williams G, Lillie J, Kelly-Blake K, Williams MV, Holmes-Rovner M. Decision aids for benign prostatic hyperplasia: applicability across race and education. Med Decis Making 2004;24:359-66], preferences for BPH treatment options were assessed. METHODS: One hundred and sixty men stratified by race and education completed a semi-structured interview that included assessments of treatment preferences. RESULTS: Most men initially and ultimately favored watchful waiting over other options, and 56.6% never changed their preference rank orders while viewing the videotape. BPH severity in context of treatment risk avoidance, efficacy, and expert opinion factors were frequently cited reasons for preference orders. Lesser education was associated with higher likelihood of changing preferences (r = -.30, p < .001), and percent increase in BPH knowledge pre- to post-videotape was weakly associated with fewer non-dominant preference shifts (r = -.19, p < .05). CONCLUSION: Conservatism regarding BPH treatment is moderated by context-specific factors, including new information. PRACTICE IMPLICATION: Counseling in a provider-patient partnership model should address both sources of variance in men's treatment preferences.

Black People↗
PubMed2005

Health, wealth and fairness based on gender: the support for ethical principles.

Sex differences in health, and the reality of a gender system, are well-known, but we know little about how this connects to opinions on fairness and desired change. This study aims to explore two principal questions: how to compare the position of women and men within-state and how to choose between-states, where a state is defined as a situation in which individuals have a particular set of resources, rights and duties, and if components in the set are altered, a new state for the same individuals appears. Based on various normative rules (monistic view or separate spheres, equity as choice or ethics of care, equity by attainment or shortfall; variants of welfarism, feminism and conservatism), a survey among Swedish public health workers was carried out. The results demonstrate a major rejection of the idea of compensation between health, power, influence and resources, and of considering past processes when judging fairness as to women and men. Moreover, most respondents believe that a biologically based difference in health is fair and reject health maximization as a guiding principle. The support for gender equality is strong when contrasted with the conservative goal, and subsists when contrasted against the Pareto criterion and trading-off health/income as well. Results that call for additional research and exchange of views include that common notions in research and policy-making are rejected by a majority, and that females and males differ considerably when judging change from a societal perspective.

Data Collection↗
PubMed2006

Macroevolution of plant defense strategies.

Theories of plant defense expression are typically based on the concepts of tradeoffs among traits and of phylogenetic conservatism within clades. Here, I review recent developments in phylogenetic approaches to understanding the evolution of plant defense strategies and plant-herbivore coevolutionary interactions. I focus particularly on multivariate defense against insect herbivores, which is the simultaneous deployment of multiple traits, often arranged as convergently evolved defense syndromes. Answering many of the outstanding questions in the biology of plant defense will require generating broad hypotheses that can be explicitly tested by using comparative approaches and interpreting phylogenetic patterns. The comparative approach has wide-spread potential to reinvigorate tests of classic hypotheses about the evolution of interspecific interactions.

Animals↗
PubMed2005

Both host-plant phylogeny and chemistry have shaped the African seed-beetle radiation.

For the last 40 years, many authors have attempted to characterize the main patterns of plant-insect evolutionary interactions and understand their causes. In the present work on African seed-beetles (Coleoptera: Bruchidae), we have performed a 10-year field work to sample seeds of more than 300 species of potential host-plants (from the family Fabaceae), to obtain bruchids by rearing. This seed sampling in the field was followed by the monitoring of adult emergences which gave us the opportunity to identify host-plant use accurately. Then, by using molecular phylogenetics (on a combined data set of four genes), we have investigated the relationships between host-plant preferences and insect phylogeny. Our objectives were to investigate the level of taxonomic conservatism in host-plant fidelity and host-plant chemistry. Our results indicate that phylogenetically related insects are associated with phylogenetically related host-plants but the phylogeny of the latter cannot alone explain the observed patterns. Major host shifts from Papilionoideae to Mimosoideae subfamilies have happened twice independently suggesting that feeding specialization on a given host-plant group is not always a dead end in seed-beetles. If host-plant taxonomy and chemistry in legumes generally provide consistent data, it appears that the nature of the seed secondary compounds may be the major factor driving the diversification of a large clade specializing on the subfamily Mimosoideae in which host-plant taxonomy is not consistent with chemical similarity.

Adaptation, Biological↗
PubMed1984

Changing times in surgical management of bronchopulmonary carcinoid tumor.

The bronchopulmonary carcinoid tumor occurs at all levels from trachea to lung periphery. It should be managed by conservatism in airway or lung resection. The long-term survival is excellent: 82% at 10 years in this series of 111 resected patients. The atypical carcinoid tumor (10% of this series) has a more ominous prognosis and requires special surgical attention. Six conceptual changes in the evolution of management of the tumor are presented (the "changing times").

Adolescent↗
PubMed1983

Why are radiologists in the UK not using computers in their departments?

The value of administrative support computers in radiology departments has been evident, particularly in the United States, for more than a decade. It is difficult to understand why so little interest appears to have developed in this country; it is, perhaps, our inherent conservatism. The advent of the inexpensive microprocessor with a wide range of program packages has set the scene for an expansion of the use of computing in a wide range of clerical tasks. This article sets out to describe the various applications which we have demonstrated to be particularly suitable for incorporation into a computer system and suggests a number of additional applications which may be appropriate to particular radiology departments.

Computers↗
PubMed2002

The role of abstract syntactic knowledge in language acquisition: a reply to Tomasello (2000).

In his paper "Do young children have adult syntactic competence?" Tomasello (Cognition 74 (2000) 209) interprets young children's conservatism in language production as evidence that early language use, and verb use in particular, are based entirely on concrete lexical representations, showing no evidence of abstract syntactic categories such as "verb" or "transitive sentence". In this reply, I argue that Tomasello's interpretation depends on three questionable premises: (a) that anyone with a robust grammatical category of verbs would use new verbs in unattested sentence constructions; (b) that there are no reasons other than lack of syntactic competence for lexical effects in language use; and (c) that children always interpret a new verb presented in the context of an action on an object as a causal action verb, and therefore as one they should use transitively. I review evidence against all of these assumptions. Tomasello's data, among others', show that children indeed learn item-specific facts about verbs and other lexical items - as they must, to become competent speakers of their native language. However, other data suggest that more abstract descriptions of linguistic input also play a role in early language use. To achieve a complete picture of how children learn their native languages, we must explore the interactions of lexical and more abstract syntactic knowledge in language acquisition.

Child, Preschool↗
PubMed2000

Internal transcribed spacer rDNA can be used to infer the phylogenetic relationships of species within the genus Nematodirus (Nematoda: molineoidea).

Sequences of the first internal transcribed spacer rDNA were characterised for four veterinary important species of gastrointestinal nematodes from the genus Nematodirus. The sequence data were combined with previously published data of the second internal transcribed spacer to determine whether these rDNA regions provided a suitable number of informative characters to determine the phylogenetic relationships of species within the genus. A total of 32 alignment positions of the first internal transcribed spacer data set and 33 characters from the second internal transcribed spacer data set were informative in phylogenetic analyses. Irrespective of whether the data from each spacer were analysed separately or combined, only one most parsimonious tree was produced, with the relationships of the four species fully resolved. In addition, several regions of conservatism in the first internal transcribed spacer sequence among the four Nematodirus species suggests that this rDNA region may also provide phylogenetic information for higher taxonomic levels within the Molineoidea.

Animals↗
PubMed1990

Koinophilia groups sexual creatures into species, promotes stasis, and stabilizes social behaviour.

In a population whose members' genomes are subject to degradation by random mutations, the heritable vigour of the most common phenotypes is unquestionable (though not necessarily optimal), and that of fringe individuals is always suspect. Natural selection will therefore support the evolution of an affinity for modal mates (i.e. koinophilia). The population's genetic make-up can then not readily be invaded by non-cryptic mutations. This imposes considerable phenotypic conservatism on sexually reproducing creatures, and inexorably canalizes them into sexually isolated, phenotypically distinct species. The model predicts, and the empiric data confirms, that the phenotypic gaps between largely monomorphic sexual species do not characterize the taxonomy of longstanding apomicts, where variation below the genus level is often continuous. The bias against the propagation of all forms of phenotypic novelty and non-conformity stabilizes social animals against selfish mutants, thus removing the barriers to the evolution of "group adaptations".

Adaptation, Biological↗
PubMed1991

General principles of antimicrobial therapy.

Treatment with antimicrobial agents must be tailored to the individual patient, the site of infection, and the etiologic organism involved. Effectiveness, toxicity, and cost are the basic considerations in choosing a drug. Because initiation of therapy often cannot be delayed until microbiologic studies have been performed, empiric treatment should be sufficiently broad to cover the most likely pathogens, based on the site of infection and the type of host. Definitive therapy may differ from initial therapy and should be instituted as soon as specific laboratory and clinical data are available. Information about allergic reactions to drugs should be elicited; because of the numerous families of antimicrobial agents currently available, most infections in patients with drug allergies can be treated with adequate substitutes. Cautious conservatism is advocated in the use of new antimicrobial agents. The effects of new agents on the microbial ecology and the hospital environment should be considered.

Anti-Bacterial Agents↗
PubMed1987

General principles of antimicrobial therapy.

Use of antimicrobial agents must be tailored to the individual patient, site of infection, and etiologic organism. The choice of drug should be based on efficacy, safety, low toxicity, and acceptable cost. Empiric therapy should be broad enough to cover the pathogens that are suspected of causing the infection, based on the site of infection and the type of host. Definitive therapy may differ from initial therapy and should be started as soon as specific laboratory and clinical data are available. Cautious conservatism is advocated with regard to the use of new antimicrobial agents. The effects of the agents on the microbial ecology and hospital environment should be considered. Judicious use is necessary to prevent antimicrobial pollution.

Anti-Bacterial Agents↗
PubMed1996

Selective surgical management of zone II gunshot injuries of the neck: a prospective study.

BACKGROUND: The management of penetrating neck trauma remains controversial, with many studies supporting either mandatory exploration or selective conservatism. METHODS AND RESULTS: This is a prospective study of 75 patients with gunshot injuries to zone II of the neck. Forty patients (53.3%) underwent immediate exploration because of clinical indications or positive initial investigations. A 7.5% incidence of unnecessary explorations, a 5% mortality rate, and average hospital stay of 10.5 days were noted. Thirty-five patients with negative clinical or investigational findings underwent observation with constant monitoring. A 5.7% incidence of missed injuries, no mortality, and an average hospital stay of 3.5 days were noted for these patients. CONCLUSIONS: We suggest that conservative management in gunshot injuries confined to zone II of the neck selectively supplemented by appropriate investigations is a viable proposition in this type of injury. Further contemporary studies reporting specifically on this injury will enable us to reach statistically significant conclusions.

Adolescent↗
PubMed1977

Paragangliomas of the neck: clinical and pathologic analysis of 116 cases.

Neck tumors developing from the paraganglion system are best called paragangliomas. They may be described further as to site of origin and as to whether they are functioning or nonfunctioning. Review was made of 116 cases in which operation for paraganglioma was performed at the Mayo Clinic. The diagnosis depends upon demonstration of a lateral neck mass, elimination of other causes, and a tumor blush on angiography. Screening tests should be done to determine whether the tumor is producing epinephrine. Surgical management should be selective, depending upon the location and involvement of surrounding structures, particularly the carotid artery system. A conservative approach is indicated for those patients whose tumor surrounds the carotid vessels, because the risk of complications is greater than the risk of leaving the tumor in the neck. Conservatism is also indicated for patients in the older age group, because of the slow growth of these tumors and the low incidence of malignancy.

Adolescent↗
PubMed1978

Modified radical mastectomy.

The recent history of operations for breast cancer indicates a growing trend toward conservatism. The modified radical mastectomy achieves the goal of removing all evidence of cancer in the breast involved and removes the regional lymph nodes for accurate staging of the disease. In addition, it provides a cosmetic result superior to that of the standard radical mastectomy. Breast reconstruction may be undertaken at a later time with excellent result. The 5 and 10 year survival rates of comparable groups of patients after modified radical mastectomy and standard radical mastectomy appear to be almost identical.

Biopsy↗
PubMed2001

Opportunities for a probabilistic risk assessment of chemicals in the European Union.

In risk assessment of new and existing substances, it is current practice to characterise risk using a deterministic quotient of the exposure concentration, or the dose, and a no-effect level. A sense of uncertainty is tackled by introducing worst-case assumptions in the methodology. Since this procedure leads to an assessment with an unknown degree of conservatism, it is advisable to deal quantitatively with uncertainties. This paper discusses the advantages and possibilities of a probabilistic risk assessment framework, illustrated with an example calculation. Furthermore, representatives of EU Member States and the chemical industry were interviewed to find out their views on applying uncertainty analysis to risk assessment of industrial chemicals.

Environmental Exposure↗