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PubMed1984

Italian occupational health: concepts, conflicts, implications.

This paper examines Italy's worker-based model for occupational health, especially its key concepts and its relation to social conflict. It briefly reviews the history of three approaches to occupational health in Italy: university-based, industry-based, and government-based. It then analyzes the worker-based approach, which emerged in the late 1960s and early 1970s as worker groups and trade unions mobilized around new concepts of occupational health. Five key concepts are discussed: the workers' homogeneous group; workers' subjectivity; the use of contract language; the development of local occupational health institutions; and the use of occupational hazard risk maps. The analysis illustrates how the social processes of mobilization and institutionalization affected the ideas and structures of Italian occupational health. Worker mobilization in Italy produced ideological changes in the nation's occupational health system, institutional changes in universities and governments, and legislative changes at national and local levels. The institutionalization of reforms, however, created new conflicts and problems and tended to restrict worker participation and promote expert intervention. The paper concludes with a brief outline of the history of occupational health approaches in the United States and then discusses the implications of the five Italian concepts for US occupational health policy.

Attitude↗
PubMed1999

The efficiency concept in pharmacodynamics.

The classic approach to describe the pharmacological response to a drug is to analyse its concentration-effect relationship, using a variety of possible models such as maximum effect (Emax) models or sigmoid Emax models. The aim of this review is to discuss an alternative way of describing the pharmacological effect in terms of effect per unit of drug concentration, instead of simple effect. This variable is called efficiency, analogous with concepts used in other fields. The pharmacodynamic model for efficiency is derived from the sigmoid Emax model and is dependent on the same parameters. Since the sigmoid Emax model incorporates 'the law of diminishing returns', requiring ever higher concentrations to increase the effect by a given percentage, efficiency is bound to decrease with increasing concentrations. However, as a mathematical consequence of its derivation from the sigmoid Emax model, efficiency also has a maximum value, which can be expressed as a function of the slope factor (s) and drug concentration associated with half the maximum effect (C50), provided that the slope factor is greater than 1. The efficiency concept is potentially applicable to all drugs and particularly useful for those that follow concentration-effect relationships according to Emax or sigmoid Emax models. Most experience has been obtained with loop diuretics, especially with furosemide (frusemide). Slow administration of furosemide, leading to slow excretion of the drug, has been shown, in many studies, to significantly increase the total diuretic effect per amount of drug recovered in urine. In this review, some examples of the applicability of the efficiency concept to other drugs, such as antibacterials, opioids and antineoplastics, are discussed. In addition to pharmacodynamically varying efficiency, other saturable processes, such as the formation of active metabolites and saturable transport, may form a basis for the application of the efficiency concept. The efficiency of a drug dosage may also be influenced by tolerance and counter-regulation produced by the drug. All these factors contribute to schedule dependency. It is concluded that the shape of the time course of drug presentation to its site of action is an independent determinant of overall response. The possibility of adjusting the drug input profile to maximise therapeutic effect per dose and to separate cumulated therapeutic from cumulated adverse effects should be considered in designing administration schedules and in drug development.

Biological Availability↗
PubMed2006

Effect of different river water quality model concepts used for river basin management decisions.

n this research the applicability of two different water quality concepts, a QUAL2E-based and a RWQM1-based water quality model is evaluated in terms of management decisions. The Dender river in Belgium serves as a case study for the application of the methodology. By using sensitivity analysis on both model concepts the important processes are revealed. Further, the differences between the predictions for a future scenario are analysed. The scenario chosen here is a reduction in fertiliser use of 90%, which reduces the diffuse pollution. This way, the advantages or disadvantages of using one concept against the other for this scenario are formulated. It was found that the QUAL-based models are more focussing on algae processes while the RWQM1 also takes into account processes in the sediment. Further the QUAL-based models are easier to calibrate, especially when only a small amount of data is available. Both concepts lead to more or less the same conclusions. However for some periods the differences become important and to reduce the uncertainty in those periods, more efforts should be spent in calibration and in better detection of parameters concerning sediment processes and diffusion.

Belgium↗
PubMed2001

Role of biotransformation in conceptal toxicity of drugs and other chemicals.

Many developmental toxicants and teratogens require prior metabolism to reactive species or free radicals to exert toxicity. Thus the knowledge of conceptal biotransformation is absolutely critical in understanding toxicity of these chemicals. Due to extremely low content of cytochrome P450 in the embryo and other conceptal tissues, the research focus in recent years has steadily shifted toward enzymes capable of peroxidative oxidation of xenobiotics. At least three enzymes viz. lipoxygenase, peroxidase and prostaglandin synthase, each capable of peroxidative xenobiotic metabolism, occur in conceptal tissues of man and laboratory animals in biologically significant amounts. This review mainly summarizes the available information on the enzymatic bioactivation of teratogens and developmental toxicants belonging to diverse classes such as drugs, pesticides, environmental contaminants, industrial and other chemicals. Additionally, some discussion is devoted toward issues such as drug-drug interactions. The emerging new information on the peroxidative glutathione conjugate formation from xenobiotics is also presented. A critical need for gathering more information on this subject using different enzyme preparations from human conceptal tissues is stressed to avoid tragedies in the future.

Animals↗
PubMedDate not supplied

The relationship between language and disease concepts.

The Sapir-Whorf hypothesis, well-known in anthropological linguistics, postulates that language may not only describe the world we inhabit but also mould the way we experience it. This paper argues that an individual's language may similarly determine his conception of disease. Possible relationships between linguistic features and disease concepts are cited for the Eskimo, the Navaho, and the Chines, and it is suggested that, in European languages, the extensive use of spatial metaphors to express abstract concepts may encourage a more rigid categorization of disease and inhibit the ability to conceive of multiple factors in disease causation. The use of nouns rather than verbs to express the idea of illness could lead to a static view of disease and tends to separate illnesses as distinct entities rather than defining them as aspects of bodily functioning. The bipolar structure of Indo-European languages, setting subject against predicate and noun against verb, may play a part in the persistence of the mind-body dichotomy and restrict the holistic perception of man with nature. These linguistic features, in leading to a conception of disease as a rigidly defined, unchanging, unicausal thing, may encourage an over-use of surgery and lead to difficulty in perceiving social and psychological factors in disease.

Attitude of Health Personnel↗
PubMed1992

African-American, Anglo-American, and Anglo-Canadian grade 4 children's concepts of old people and of extended family.

A cross-national study of 104 fourth grade children's concepts of old people and extended family was conducted in Canada and the United States, using the Children's Attitudes Toward the Elderly Scale (CATE), and a modified version of the Gilby and Pederson (1982) Family Concept Interview. Both Anglo-American and African-American children were included in the U.S. sample. Results indicated that Anglo-American and Anglo-Canadian children were significantly more similar in their attitudes toward the elderly and their concepts of family than African-American and Anglo-American children. In comparison with the other two cultural groups, Anglo-American children were significantly more likely to include extended family members in their concept of who is family; Anglo-Canadian children had a significantly higher level of age discrimination ability; and African-American children showed a trend toward more positive attitudes toward older people. Overall findings of negative attitudes toward old people were consistent with earlier studies. The implications of children's ageist attitudes for increasingly aging Western societies are noted, particularly given impoverished children's potential need for extrafamilial social supports.

Black or African American↗
PubMed1978

Decision-sharing in elementary school children: effects on body-concept and anxiety.

To determine the effects of teacher-directed and decision-sharing models of instruction on the development of body-concept and reduction of anxiety 99 Greensboro public school children in Grades 3 and 4 participated in either a movement program in which the teacher made all the decisions or in a program where they shared in the decision-making. The Cheffers adaptation of Flanders' Interaction Analysis System was used to verify the two treatments. The dependent variables were measured by Osgood's semantic differential for body-concept measures, and Sarason's General Anxiety Scale for Children. There was no significant difference between the groups for improvement in body-concept. Also, girls have more positive concepts about their bodies than do boys. Anxiety scores indicated that levels in fourth-grade children appear to be reduced when exposed to a teacher-directed model. However, a decision-sharing approach had a significant effect on reducing anxiety levels in third-grade children.

Anxiety↗
PubMed1980

Spatial concept learning in preschool children: motoric experiences and verbal repetition as adjuncts to passive listening.

32 preschool children were matched by age, sex, and pretest scores on spatial concept knowledge. Four groups were (a) instruction (see and hear) only, (b) verbal repetition, (c) fine motor treatment (hand manipulation), and (d) gross motor treatment (body movement). The 11 spatial concepts studied were in front of, behind, beside, on top of, under, around, through, right, left, forward, and backward. There was no difference in performance between groups given instruction only and verbal repetition. The motoric groups learned more than the non-motoric groups. Older children knew more concepts initially but did not learn more new concepts than younger children.

Age Factors↗
PubMed1991

Empathy, others-concept, and prosocial orientation.

The relationship between 56 nursing students' empathy and their others-concept was investigated to establish ties to a broader construct, prosocial orientation. The female Caucasian nursing students were rated for empathy by two clinical instructors. They were also given the Paired Hands Test to assess their others-concept. The students with the higher empathy ratings had more positive others-concepts. The responses of the low empathy group to the Paired Hands Test indicated a much stronger tendency to perceive and interpret social interactions negatively. Besides practical implications for nurses and other helping professionals, these findings have theoretical ramifications as well. Others-concept has been shown previously to be related to a cluster of variables such as positive social behavior and moral judgment. Evidence of the relationship to empathy helps to tie this cluster to the prosocial orientation construct as a base for further research.

Adult↗
PubMed1992

Relationships between scores on the DIAL-R concepts scale and SRA scores.

42 children, brought for preschool screening from rural north central Kansas school districts, were administered the concepts area of the Developmental Indicators for the Assessment of Learning--Revised, and after the children had started school, the SRA scores were collected from their files. The 20 boys were absent more often than the 22 girls during Kindergarten. There was no sex difference on the concepts area of the DIAL--R. In Grade 1 girls had higher SRA Composite scores. The scores on the DIAL--R concepts area correlated (.36 to .68) with Kindergarten SRA scores and Grade 1 SRA scores, in part, because the DIAL--R concepts area covers the material presented and learned in Kindergarten and screens for material presented in Grade 1. Screening devices may be a useful first step in developing comprehensive assessment plans for children.

Achievement↗
PubMed1996

Relationship between circulating progesterone and conception at the first postpartum estrus in young primiparous beef cows.

The objective of this study was to determine whether patterns of change in concentration of progesterone in circulation of primiparous beef cows were related to conception rates at the first postpartum estrus. Data were collected over 2 yr from crossbred primiparous 2-yr-old cows (n = 77). Cows were artificially inseminated when estrus was detected between 3 and 20 (yr 1) or 3 and 23 (yr 2) wk after parturition. Cows were exposed to intact bulls for 32 (yr 1) or 21 d (yr 2) after the periods of AI, and estrus detection also occurred during the period when natural mating occurred. After parturition, blood samples were collected twice weekly to determine time of transient (less than 1 wk) and sustained increases (more than 1 wk) in progesterone of more than 1 ng/mL of serum. Mean times from parturition to transient increase in progesterone, first estrus, conception, and sustained increase in progesterone were 91, 100, 108, and 105 d, respectively. Sixty-four percent of the cows conceived as a result of AI at the first estrus that was detected after parturition, 32% conceived at a subsequent estrus, and 4% failed to conceive. In 31.1% of the cows, a transient increase in progesterone was not detected before the first estrus after calving. Conception as a result of AI at the first estrus after calving was less if a transient increase in progesterone did not precede estrus (76 vs 41%; P < .01). These data indicate that the majority of cows have increases in progesterone before the first postpartum estrus. If the transient pre-estrus increase in progesterone occurs in postpartum cows, there seems to be an enhanced conception rate as compared with cows without the increase in progesterone before their first estrus following parturition.

Aging↗
PubMed2005

Effect of administration of human chorionic gonadotropin after artificial insemination on concentrations of progesterone and conception rates in beef heifers.

The objective of this study was to determine whether administration of hCG approximately 5 d after AI would increase plasma progesterone concentrations and conception rates in beef heifers. Heifers from two locations (Location 1: n = 347, BW = 367 +/- 1.72 kg; Location 2: n = 246, BW = 408 +/- 2.35 kg) received melengestrol acetate (0.5 mg.heifer(-1).d(-1)) for 14 d and an injection of PGF2alpha (25 mg i.m.) 19 d later. Heifers were observed for estrus continuously during daylight from d 0 to 4.5 after PGF2alpha and artificially inseminated approximately 12 h after the onset of estrus. Half of the heifers inseminated at Location 1 were assigned randomly to receive an injection of hCG (3,333 IU i.m.) 8 d after PGF2alpha, and a blood sample was collected from all heifers 14 d after PGF2alpha for progesterone analysis. Half of the heifers inseminated at Location 2 were administered hCG on d 9 after PGF2alpha, and a blood sample was collected from all heifers 17 d after PGF2alpha. Heifers at Location 1 had a 94% synchronization rate, exhibited estrus 2.45 +/- 0.03 d after PGF2alpha, and received hCG 5.55 +/- 0.03 d after AI. Heifers at Location 2 had an 85% synchronization rate, exhibited estrus 2.69 +/- 0.03 d after PGF2alpha, and received hCG 6.31 +/- 0.03 d after AI. Progesterone concentrations were greater (P < 0.01) for hCG-treated heifers than for controls at both locations (8.6 vs. 4.6 ng/mL for treatment vs. control at Location 1, and 11.2 vs. 5.6 ng/mL for treatment vs. control at Location 2). Pregnancy status was determined by ultrasound approximately 50 d after AI. Conception rates (65 vs. 70% for treatment vs. control, respectively) did not differ at Location 1. Conception rates tended (P = 0.10) to be increased with hCG treatment at Location 2 (61 vs. 50% for treatment vs. control, respectively). A second experiment was conducted with 180 heifers at a third location to determine the effects of hCG administration 6 d after timed insemination at approximately 60 h after PGF2alpha in heifers synchronized as in Exp. 1. Pregnancy rate to timed AI did not differ between hCG-treated (62%) and control heifers (59%). Final pregnancy rate after timed AI and bull exposure (92%) was not affected by treatment. In summary, administration of hCG 5 to 6 d after AI did not improve conception or pregnancy rates at two out of three locations evaluated, suggesting insufficient progesterone is not a major factor contributing to early pregnancy failure in beef heifers.

Animals↗
PubMed2006

Conception rates to artificial insemination in primiparous, suckled cows exposed to the biostimulatory effect of bulls before and during a gonadotropin-releasing hormone-based estrus synchronization protocol.

The objective of these studies was to evaluate whether exposing primiparous, suckled beef cows to the biostimulatory effect of bulls alters breeding performance associated with an estrus synchronization protocol that included GnRH followed 7 d later by PGF(2alpha) and fixed-time AI (TAI). This was a composite analysis of 3 experiments that evaluated (1) the effects of bull exposure at different days after calving (yr 1); (2) the biostimulatory effects of bull excretory products (yr 2); and (3) the biostimulatory effects of familiar and unfamiliar bulls (yr 3) on the resumption of ovarian cycling activity. In all studies, cows were exposed (biostimulated; n = 94) or not exposed (nonbiostimulated; n = 67) to bulls or excretory products of bulls for at least 60 d before the beginning of the estrus synchronization protocol. Average calving day did not differ among years and was 52 +/- 5 d. Year did not affect the proportions of biostimulated and nonbiostimulated cows that were cycling at the beginning of the estrus synchronization protocol; however, a greater (P < 0.001) proportion of biostimulated than nonbiostimulated cows were cycling at this time. In each year, cows were given GnRH followed by PGF(2alpha) 7 d later. Cows were observed for estrus twice daily (am and pm) after PGF(2alpha). Cows that exhibited estrus before 54, 60, and 64 h after PGF(2alpha) were inseminated by AI 12 h later in yr 1, 2, and 3, respectively. Cows that failed to show estrus were given GnRH and TAI at 62, 72, and 72 h after PGF(2alpha) in yr 1, 2, and 3, respectively. Conception rates were determined by transrectal ultrasonography 35 d after TAI in each year. The percentages of cows that exhibited estrus after PGF(2alpha) and before TAI, the interval from PGF(2alpha) to estrus, and the percentages of cows inseminated 12 h after estrus or at TAI did not differ between biostimulated and nonbiostimulated cows and were 51%, 54.7 +/- 7.3 h, 35%, and 65%, respectively. Conception rates for cows bred by AI 12 h after estrus did not differ between biostimulated and nonbiostimulated cows; however, the TAI conception rate was greater (P < 0.05) for biostimulated cows (57.6%) than for nonbiostimulated cows (35.6%). We conclude that TAI conception rates in an estrus synchronization protocol that includes GnRH followed 7 d later by PGF(2alpha) may be improved by the biostimulatory effect of bulls in postpartum, primiparous cows.

Animals↗
PubMedDate not supplied

Historical concept analysis of empathy.

An analysis of the concept empathy was performed on archival, narrative accounts of Civil War nursing care using concept analysis strategies. Archival model cases are presented with elucidation of critical attributes, antecedents and consequences, and empirical referents of the concept. The antecedent phenomena of patient cues and consequent phenomena of patient responses serve to clarify instances of nurse empathy and establish preliminary and terminal boundaries of the concept. Empirical referents of the critical attributes identification, introjection, and intervention further explicate this abstract construct. Analysis of contrary, related, and borderline cases extracted from the historical accounts serve to clarify empathy. Most notable to the analysis is the existence of nursing interventions as a critical attribute and the nature of patient responses. Preliminary examination of the model cases indicates patient outcomes improve when empathy is extant in the interaction.

Empathy↗
PubMed1990

Clomiphene treatment for women with unexplained infertility: placebo-controlled study of hormonal responses and conception rates.

One hundred and eighteen patients with unexplained infertility were treated with clomiphene (Clomid, Merrell) in a randomized placebo-controlled cross-over study lasting up to 3 months with each preparation. Compared with placebo, clomiphene led overall to a 66% increase in mid-luteal serum progesterone levels (from mean 43 nmol/l to 71 nmol/l, p less than 0.001) and a 53% rise in the 3-month cumulative conception rate (from 14.6% to 22.33%, p less than 0.05). The greatest relative increase in conception rates with clomiphene was in women with infertility lasting more than 3 years (3-month rates from 2.9% to 14.4%, p less than 0.05). Differences in conception rates were not related to the rises in progesterone, and there was no carryover effect of clomiphene into the following placebo cycles in terms of progesterone levels or conceptions. The findings suggest that couples with unexplained infertility of less than 3 years duration are essentially normal, but with more than 3 years duration there is often a subtle disorder of ovulation that is corrected by clomiphene therapy.

Adult↗
PubMed1989

Does endorsement of the disease concept of alcoholism predict humanitarian attitudes to alcoholics?

It has been widely assumed that the disease concept of alcoholism is a powerful vehicle for the promotion of humanitarian attitudes to alcoholics. However, Crawford and Heather have argued that individual differences in attitudes to alcoholics are liable to be a reflection of broader attitudes to deviancy rather than a function of endorsement/rejection of a disease conception. This argument was subjected to empirical scrutiny by means of a questionnaire distributed to 200 members of the public. The questionnaire (1) measured attitudes to four deviant groups--alcoholics, drug addicts, compulsive gamblers, and juvenile delinquents--and (2) recorded whether respondents endorsed or rejected a disease conception of these deviant conditions. Attitudes to the non-alcoholic deviant groups were better predictors of humanitarian attitudes to alcoholics than was endorsement of a disease conception of alcoholism.

Adolescent↗
PubMed2005

Straw-thawing method interacts with sire and extender to influence sperm motility and conception rates of dairy cows.

Influence of interactions of straw-thawing method with sire and extender type (milk or egg yolk-based) on postthaw sperm motility and conception rates of dairy cows was assessed. In experiment 1, sperm from 10 Holstein sires were frozen in egg yolk citrate and heated whole-milk extenders using a split-ejaculate technique. Straws were thawed in a 37 degrees C water bath with or without 3 min of exposure to a 37 degrees C warming plate while wrapped in a paper towel (air-thaw). Percentage of motile sperm was assessed after 1 min and 3 h of incubation at 37 degrees C. In experiment 2, sperm from 3 Holstein sires were frozen in egg-yolk citrate and a nonheated whole milk extender using a split-ejaculate technique. Straws were thawed and motility was assessed as in experiment 1. Conception rates (n = 475) were compared in a single herd of Holstein cows after thawing straws in 35 degrees C water for 45 s or after air-thawing by wiping straws with a paper towel upon removal from the storage vessel and placing directly into the insemination gun. In each experiment, interactions between thaw method and sire, extender type, or both, indicated that conditions may be created that facilitate sperm tolerance of air-thaw procedures. When a significant thaw method effect was detected in either experiment, air-thaw was consistently associated with the lesser measure of sperm motility, conception, or both. In conclusion, although some sire x extender combinations seem to be tolerant of air-thaw procedures, other combinations are more sensitive, resulting in reduced postthaw sperm survival, conception rates of cows, or both, in response to air-thaw.

Animals↗
PubMed2006

Time and incidence of ovulation and conception rates after incorporating estradiol cypionate into a timed artificial insemination protocol.

Two experiments were conducted to determine the effect of estradiol cypionate (ECP), when incorporated into a conventional GnRH-PGF(2alpha)-GnRH timed artificial insemination protocol (Ovsynch), on systemic estradiol (E(2)), time and incidence of ovulation, luteal development, and conception rate in Holstein cows. Our objective was to determine if administration of 0.25 mg of ECP at the time of the second GnRH injection would effectively synchronize ovulation and increase conception rate. In Experiment 1, lactating Holstein cows (n = 23; 58.7 +/- 1.2 d in milk) were synchronized with PGF(2alpha) (at d -10). Ten days later, Ovsynch was initiated with the administration of 100 mug of GnRH (d 0) followed by PGF(2alpha) on d 7. On d 9, cows were assigned randomly to be treated with either GnRH + 0.25 mg of ECP (OVS-ECP; n = 11) or GnRH and 1 mL of cottonseed oil (OVS-C; n = 12). Ovarian activity was monitored by ultrasonography on d 0, 7, and 9. To determine the time of ovulation, ultrasound examinations were conducted at 12 and 20 h posttreatment and then at least every 3 h until either 36 h posttreatment or ovulation was observed. Blood samples were collected on d 0, 7, 9, and 16 for progesterone analysis. Blood samples also were collected at the time of treatment (d 9, 0 h) and at 6, 12, 20, and 28 h for E(2) analysis. Incidence of ovulation did not differ between treatments. Mean ovulation time relative to the second GnRH administration was similar between treatments. Serum progesterone concentration did not differ between treatments at any time. Serum E(2) concentration was not different at the time of treatment (0 h); however, mean E(2) concentration was greater for the OVS-ECP group at 6 and 12 h after treatment compared with OVS-C. In Experiment 2, lactating dairy cows (n = 333) in 3 commercial herds were randomly assigned to OVS-ECP (n = 169) or OVS-C (n = 164). Cows were inseminated 22 to 24 h posttreatment. Conception rates did not differ between treatments. Estradiol cypionate treatment was successful in increasing serum E(2) when administered at the time of the second dose of GnRH in the Ovsynch protocol. Conception rates, however, were not affected by treatment.

Animals↗