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PubMed1975

Environmental and managemental factors affecting conception rate in a subtropical climate.

Data representing 5,062 services during 1960 to 1971 in the Florida Agricultural Experiment Station dairy herd were analyzed by least squares to delineate factors affecting conception rates. Overall conception rate was 37.9%. From a set of 21 climatological measurements, the five selected as most important ranked (1) maximum temperature day after insemination, (2) rainfall day of insemination, (3) minimum temperature day of insemination, (4) solar radiation day of insemination, and (5) minimum temperature day after insemination. Warm months were more closely associated with lower conception rates than were cool months (33.7 compared to 40.1%); month effects appeared to be accounted for by the climatological measurements. Conception rates declined with age: heifers, 47.6%; young cows, 42.7%; older cows, 31.9%. No decline with advancing service number (1 to 5) occurred. Service sire and inseminator effects were detected as expected. Although breeds differed (Aryshires, 33.8; Brown Swiss, 34.6; and Guernseys, 37.0; Holsteins, 35.5; and Jerseys, 48.4%), there was no evidence of breed (Jerseys and Holsteins) by month or breed by season interactions nor was it possible to detect age by season interactions.

Animals↗
PubMed1976

Relationship of temperature and humidity to conception rate of Holstein cows in Hawaii.

Weather data and breeding records for a Holstein herd of 1300 cows in Hawaii were evaluated to determine effects of climate on reproductive performance. The dairy is in a coastal climate near latitude 21 degrees N. Average maximum temperature, relative humidity, and resulting temperature-humidity index for the warmest month of the year were 31 C, 44%, and 79. Average minimum temperature and attending values for the same period were 20 C, 96%, and 68. From late April to November, conception rates were correlated negatively with the average temperature-humidity index of each day of the estrous cycle beginning 11 days prior to breeding. Slopes of regression lines differed, suggesting varying sensitivity of conception rate to heat stress on different days of the cycle. The temperature-humidity index of the 2nd day prior to breeding was most closely correlated with conception rate. Conception rates declined from 66% to 35% as the index increased from 68 to 78. Only the temperature-humdity index of the 2nd day prior to breeding had a significant partial correlation coefficient when the index of the 2nd and 1st day prior to breeding, the day of breeding, and the day following breeding were each evaluated with the index of the others held constant.

Animals↗
PubMed1984

Factors affecting conception rate of Israeli Holstein cattle.

Environmental and genetic effects on reproductive performance were estimated. Data included records of 194,579 inseminations of cows and 56,132 inseminations of heifers in 200 kibbutz herds from 1980 to 1981. Conception status was ascertained by veterinary palpation if no subsequent parturition was recorded. With subsequent parturition, the insemination closest to 277 days before parturition was considered successful. Largest differences in conception rate were between cows (40.4%) and heifers (64.3%) and among insemination month for cows (23.5 to 51.5%). Heritabilities of sire effect on conception rate were .016 for cows and .006 for heifers. Correlations between heifers and cows were .64 for inseminator and .54 for service sire. Low correlation between heifers and cows for herd effect (.17) indicates a management problem; low correlation between heifers and cows for sire effect (.27) suggests a different genetic mechanism for fertility. Significant improvement may be achieved in fertility by selection of service sires, sires, and inseminators if evaluations are based on a large number of observations. However, the major increase of conception rate may be expected from reducing adverse effects of summer conditions on reproductive performance.

Animals↗
PubMed1990

Effect of fertirelin acetate or buserelin on conception rate at first or second insemination in lactating dairy cows.

The objective of this study was to determine if fertirelin acetate and buserelin, two GnRH agonists, improve conception rate when administered at the time of first or second AI in lactating dairy cows. The study consisted of a common protocol conducted at 10 commercial dairy farms. Approximately 150 cows within each dairy were assigned randomly in replicates to receive intramuscularly either no injection or injection of 25, 50, 75, or 100 micrograms fertirelin acetate or 10 micrograms buserelin immediately after AI. Cows were subjected to the reproductive management practices normal for each location. Cows at each location were palpated for pregnancy status at 35 to 60 d postinjection. No improvement in conception rate was detected in response to either agonist (control = 48%, fertirelin acetate = 41.5%, buserelin = 39.7%). Conception rate was unaffected by either days postpartum at injection or overall fertility of the individual herds. These observations do not support the routine use of doses of 25 to 100 micrograms fertirelin acetate or 10 micrograms buserelin at the time of first or second AI as a means to improve conception rate in lactating dairy cows.

Analysis of Variance↗
PubMed1990

Comparison of methods for the synchronization of estrous cycles in dairy cows. 2. Effects of progesterone and parity on conception.

Three experiments with 571 dairy cows indicated that significantly more primiparous cows given two prostaglandin F2 alpha injections 14 d apart conceived within 30 d of first AI than did cows given two injections 11 d apart (84 vs. 62%). Fewer multiparous cows given two injections 14 d apart and inseminated after estrus conceived than did cows given two injections and a progesterone intravaginal coil inserted 8 d after the first injection (42 vs. 66%). Fewer cows given one injection of prostaglandin and inseminated at estrus conceived than did cows given two injections 14 d apart and a progesterone coil (39 vs. 66%). Conception rates of cows given two prostaglandin injections were positively related to plasma progesterone concentrations 2 and 4 d before the second injection (r = .81 and .86). Cows with progesterone concentrations below 5 ng/ml, 2 d before the second prostaglandin injection, and synchronized by two prostaglandin injections or by two injections and a progesterone coil had conception rates of 36 and 63%, respectively. Cows with progesterone concentrations above 5 ng/ml had a conception rate of 75 and 46% in the two treatments, respectively. Conception after estrus synchronization depends on the method and on the plasma concentrations of progesterone. Progesterone coils may be used before AI to enhance fertility in cows with low progesterone concentrations.

Administration, Intravaginal↗
PubMed1993

Serum urea nitrogen and conception rate: the usefulness of test information.

Total of 627 AI in 332 Holstein cows in nine herds were used to examine the relationship between serum urea N and conception rate. Cows were assigned randomly to one of three isocaloric diets varying in protein degradability and content. The AI occurred from 50 to 150 DIM. Mean serum urea N for each cow from 50 to 150 DIM was used to examine conception rate and serum urea N. The clinical interpretation of serum urea N on conception rate is evaluated using Bayes theorem from two approaches (dichotomization vs. continuous). Test information resulting from dichotomization of serum urea N into high and low categories (maximizing the average of test sensitivity and specificity) is compared with likelihood ratio approaches allowing a continuous measure. Likelihood ratio test indicates that conception rate decreases with serum urea N of > 14.9 mg/dl, but dichotomized test suggests that the decrease does not occur until serum urea N is > 20 mg/dl.

Animals↗
PubMed1990

The effect of concept teaching in preparing nursing students for clinical practice.

This experimental study compared three strategies for concept teaching, using concepts basic to interpretation of electronic fetal monitor patterns. Generic baccalaureate nursing students from two different universities were randomly assigned to one of three treatment groups. After the treatments were conducted (instruction), students' ability to identify concepts on fetal monitor patterns was tested before they entered the clinical setting, and again 6 to 7 weeks later, at the end of their clinical experience. The treatment group receiving instruction using all teaching variables prescribed in the Tennyson-Cocchiarella model for concept attainment (Group 3), had a significantly higher mean at p less than .05 on the first test than the other two groups. Differences were maintained on the second test. In fact, the mean of Group 3 was the same on the first test (prior to entering the clinical setting) as the means of the other two groups after completion of the clinical experience.

Clinical Competence↗
PubMed2004

Self-care in elders with dementia: a concept analysis.

PURPOSE: The purpose of this study was to analyze the concept of self-care in elders with dementia through a review of nursing literature and to provide more understanding of the definition and perspectives of the concept of self-care notion in elders with dementia. METHODS: The technique developed by Walker and Avant was used as a guide in analyzing the concept of self-care. RESULTS: Attributes of self-care in dementia may include a single or group of actions needed for sustaining life, a personal effort to maintain functional independence while minimizing other's assistance, an outcome behavior from the person's interaction with inter-personal and/or contextual environment, and a functional ability that may decline in parallel to cognitive impairment. Antecedents of self-care in dementia may include at least presence of a certain degree of cognitive appraisal for the self-care needs, self-willingness for the self-care action, spatial and visual orientation, cultural pre-conception of the self-care behavior, presence of environmental context/equipment available for self-care, and sufficient time available. The consequences may include sustaining of life, feel of satisfaction, achieving independence, extended life expectancy, increased self-confidence, decreased caregiver distress and/or burden, savings in health care costs. DISCUSSION: Defining attributes and antecedents and consequences of self-care in dementia identified in this study provided empirical ground of a middle-range theory of self-care for a clinical population with dementia and generated possible hypotheses to be tested in future studies.

Activities of Daily Living↗
PubMed1992

The serum-ascites albumin gradient is superior to the exudate-transudate concept in the differential diagnosis of ascites.

OBJECTIVE: To compare the serum-ascites albumin gradient to the exudate-transudate concept in the classification of ascites. DESIGN: Prospective collection of ascitic fluid data from patients with well-characterized causes of ascites. SETTING: Hepatology inpatient and outpatient ward and consult service of a large, urban hospital. PATIENTS: A total of 901 paired serum and ascitic fluid samples were collected from consecutive patients with all forms of ascites. INTERVENTIONS: None. MAIN OUTCOME MEASURES: The utility of the serum-ascites albumin gradient and the old exudate-transudate concept (as defined by ascitic fluid total protein concentration [AFTP]) were compared for their ability in discriminating the cause for ascites formation. RESULTS: The albumin gradient correctly differentiated causes of ascites due to portal hypertension from those that were not due to portal hypertension 96.7% of the time. The AFTP, when used as defined in the old exudate-transudate concept, classified the causes of ascites correctly only 55.6% of the time. This resulted in part because the AFTP of most spontaneously infected samples (traditionally expected to be exudates) was low, and the AFTP of most cardiac ascites samples (traditionally expected to be transudates) was high. CONCLUSIONS: The exudate-transudate concept should be discarded in the classification of ascites. The serum-ascites albumin gradient is far more useful than the AFTP as a marker for portal hypertension, but the latter remains a useful adjunct in the differential diagnosis of ascites.

Albumins↗
PubMed2006

[Factors influencing student nurses' emotions toward children and their concept of motherhood].

The purpose of this study is to investigate the factors influencing the emotions of student nurses toward children in order to apply the results to their practical training, since the opportunity for contact with children has been decreasing in recent years due to the declining birth rate. 278 student nurses completed a self-administered anonymous questionnaire that consisted of their background, such as living with children and experience of contact with children, their learning process, such as finished lectures and nursing training in child and maternal care or not, 28 items from Hanazawa's scale of emotions toward children, and 27 items for the concept of motherhood. The obtained data was analyzed using the SPSS 12.0J for Windows with the Spearman's correlation coefficient, Mann-Whitney U test and Kruskal Wallis test. The valid recovery was 121 (43.5%). The negative point for the concept of motherhood was significantly lower in the group that had finished nursing training in child and maternal care than in the group without such training. On the other hand, living with children and experience of contact with children did not influence their emotions toward children or concept of motherhood. The results of this study suggest that the experiences that student nurses have some deliberate and active contacts with children and mothers during their nursing training in child and maternal care have an influence on their concept of motherhood.

Attitude↗
PubMed1999

A research programme for testing the biological homology concept.

The classical homology concept has served as a heuristic principle for organizing the enormous wealth of information on comparative anatomical patterns across a wide range of organisms. However, the classical homology concept reaches its limit as knowledge of the evolutionary, genetic and developmental processes that underlie these anatomical patterns increases. The biological homology concept places the known anatomical patterns into a mechanistic context and asserts that character identity is based on common variational properties in this chapter a research programme for testing the biological homology concept that involves the following steps is outlined: (1) identifying of two or more putative homologues is a clade; (2) determining the phylogenetic distribution of the putative homologues; (3) describing the intra- and interspecific variation patterns of each putative homologue; (4) describing the development of each putative homologue, and determining if modes of development and distribution of homologues are phylogenetically congruent; and (5) providing and testing a model of how differences in modes of development between putative homologues effect differences in variational tendencies. The goal is to demonstrate a link between developmental and variational differences of two homologues.

Animals↗
PubMed1998

Investigating a concept-based tool to enhance the process of curriculum development: an example for healthcare education.

This paper reports on a first exploration carried out in the CoMET (COncept Modelling Environment for Teachers) project to investigate the educational potential of a concept-based toolkit developed in the GALEN project. In particular, on whether such tools can offer a basis to support and enhance healthcare curriculum development. We first adapted part of the toolkit by developing a front-end user friendly interface to access the conceptual knowledge. We then collected data from an empirical study. Preliminary results suggest that the concept-based approach of the CoMET tools is viable and has several potential benefits for educational activities. Directions for further work in the use of the concept-based tool for teaching as well as learning are also discussed.

Artificial Intelligence↗
PubMedDate not supplied

[Considerations on the concept of epilepsy].

This leading article is written bearing in mind the disparities between different texts and studies on epilepsy. These concern the concept and the definition of epilepsy, although there is now little disparity in the classification of crises and syndromes. We also consider the increasing tendency to include other disorders with their own names and characteristics within the concept of epilepsy. Many of these disorders are also characterized by mental retardation, dementia and neurological deterioration. This contributes to maintain the sombre, ominous concept implicit in the world 'epilepsy' for centuries and is a major factor in the social discrimination of people with epilepsy. We suggest a concept and definition of the disorder differentiating it from epileptic crises and other processes.

Epilepsy↗
PubMed1999

Evaluation of a type definition for representing nursing activities within a concept-based terminologic system.

A terminology model is a conceptual representation that is optimized for the management of terminologic definitions. The purpose of this study was to evaluate one component of a terminology model, a type definition for nursing activity concepts. Two research questions were examined: 1) What percentage of nursing activity terms includes the three essential properties of the type definition (Delivery Mode, Activity Focus, and Recipient)? and 2) Can the nursing activity terms be reliably decomposed into the three elements of the type definition? The sample comprised 1039 non-redundant nursing activity terms collected from the health records of patients hospitalized for an AIDS-related condition. Each nursing activity term was decomposed into the three elements of the type definition by three raters. Percent agreement among the raters ranged from 91.5% to 96.2%. All terms included either an Explicit (82.0%) or Implicit (18.0%) Delivery Mode. Activity Focus was present in 95.1% of the terms in the sample. Recipient was coded as Explicit in 19.2%, Implicit in 75.9%, and Ambiguous in 4.8% of the nursing activity terms in the data set. Mapping among nursing terminologies and convergence of nursing terms within large concept-based health care terminologies has been hindered by the lack of a robust concept representation. A type definition is an essential component of such a representation. Further research is needed to refine the type definition and to incorporate it within a terminology model for nursing concepts.

Humans↗
PubMed1999

[Influence of pre-conception pregnancy planning in women with diabetes mellitus I on the number of spontaneous abortions and major congenital malformations in their children].

OBJECTIVE: The study assesses the relationship between pre-conception pregnancy planning and number of spontaneous abortions and major congenital malformations in their children. MATERIALS AND METHODS: 138 pregnancies in women with type 1 diabetes without complications or only with simple retinopathy (White B, C, D) were analyzed. Women were treated in the Outpatient Family Planning Center in Warsaw between 1988 and 1998. Thirty women were planning the pregnancy prior to conception, 108 registered already when pregnant. The groups compared did not differ statistically in age, duration of diabetes or diabetic angiopathy. Mean values of HbA1C in consecutive trimesters were: 6.40%, 5.84%, 5.67% in the group of patients planning the pregnancy and 6.99%, 6.29%, 6.15% in the non-planning group. The differences were statistically significant (p < 0.05, p < 0.05, p < 0.01). RESULTS: In the pre-conception group there were no spontaneous abortions and no and major congenital malformations. Mean value of HbA1C in early pregnancy was significantly higher in women with spontaneous abortions than in the remaining women in the non-planning group (respectively 7.9% and 6.9%). Also, mean value of HbA1C in early pregnancy was significantly higher in women who gave birth to children with major congenital malformations than in women had healthy children (respectively 8.23% and 6.81%, p < 0.05). CONCLUSION: Pre-conception pregnancy planning improves metabolic control during pregnancy and decreases the rate of spontaneous abortions and major congenital malformations.

Abortion, Spontaneous↗
PubMed1999

[A dispute about the concept of 'disease' in Dutch Journal of Medicine, 1863].

Professor Schrant, in his inaugural lecture held in Leiden in 1862, brought under discussion the views held at that time about the concept of 'disease'. These were determined on the one hand by empiricism, experience gained at the bedside and the dissecting table, and on the other by the 'ontological disease concept' which saw disease as an autonomous being with characteristic properties. Schrant, however, regarded diseases as a physiological experiment happening by coincidence, as an 'abnormal way of life of the animal body'. This view was criticized in the Nederlandsch Tijdschrift voor Geneeskunde by, among others, the pathologist Koster in Utrecht, who wished to regard disease as an abstraction, a concept required to designate a group of symptoms and organic alterations by a single word. Assigning the concept of disease its own identity alarmed him. At present the discussion is not closed, but owing to the stormy developments in diagnostics and treatment in medical practice there is no longer leisure for medical-philosophical discussions.

Disease↗
PubMed2000

[Testing, estimating, "significance"--concept and language of medical biometry].

The justification for the application of medical treatments and diagnostic methods has gained importance during the last decades. Together with scientific argumentations also the concepts of medical statistics have found a widespread use and are nowadays indispensible tools for clinical research. In publications of clinical trials, epidemiological investigations and animal experiments p-values, statistical tests and confidence intervals help the reader to evaluate the significance and relevance of the provided results. A prerequisite is a clear understanding of the concepts underlying these methodological terms. This paper presents the basic concepts of medical statistics and demonstrates the conclusions that can be drawn with the aid of these concepts.

Biometry↗
PubMedDate not supplied

[August Weismann's concept of germ plasma as the basic reason for the inadequacy of neo-Darwinism].

Neo-Darwinism is a result of synthesis of Darwinian concept of natural selection with Weismannian concept of germ plasma. The concept of germ plasma is based on a hypothesis that phenotypic traits are completely determined by genes. Hence, neo-Darwinism describes evolution as a process of alternation of gene frequencies under the effect of natural selection. This is an inadequate approach to the study of evolution. In the course of evolution, genes change their functions, whereas phenotypic characters change their corresponding genes. As a result, every step of evolutionary transformation changes the structure of phenotype-to-genotype correspondence. Therefore, phenotypic evolution cannot be described in genetic terms, the same as to human languages cannot be translated one into another whenever the meaning of words is constantly changing. Consequently, Weismannian germ-plasma concept adequately describes the relation of characters to genes only during stasis, but is inapplicable to evolution.

Animals↗