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PubMed1998

Average daily gain, blood metabolites, and body composition at first conception in Hereford, Senepol, and reciprocal crossbred heifers on two levels of winter nutrition and two summer grazing treatments.

Hereford (n = 48), Senepol (n = 42), and reciprocal crossbred (n = 34) heifers from two consecutive calf crops were stratified by breed, age, and BW to receive bahiagrass (Paspalum notatum) hay offered free choice and 150 mg monensin x heifer(-1) x d(-1) in addition to either 2.27 kg x heifer(-1) x d(-1) of a 75% cracked corn and 25% soybean meal mixture (CS) or .91 kg x heifer(-1) x d(-1) of soybean meal (SBM). Heifers in each treatment were divided into two winter pasture replicates and exposed to fertile bulls. In spring of each year, one-half of the heifers from each winter treatment were allotted to either a continuous (CONT) or rotational (ROTA) grazing system on bahiagrass pastures for the summer phase of the study. Heifers supplemented with CS had higher ADG from the beginning of the study to first conception than heifers fed SBM (.39 vs .31 +/- .02 kg/d; P < .01). Heifers fed CS were younger at first conception than SBM heifers (500 vs 563 +/- 32 d of age; P < .05) but had similar BW (312 vs 317 +/- 7 kg; P > .10). During the 2-yr study, a subset of Hereford (n = 12), Senepol (n = 15), and reciprocal crossbred (n = 14) heifers were subjected to urea space measurements to determine body composition at first conception. Change in body composition over time was analyzed by regression and body composition at first conception was predicted from these regressions. At first conception, percentage of empty body fat was not affected by treatment or year; however, percentage of empty body fat tended to be higher in crossbred than in Hereford and Senepol heifers (16.6 vs 14.3 and 14.4 +/- .94%; P < .10). Stepwise regression of BW, body condition score (BCS), fat thickness (determined by ultrasound), and body composition at first conception on age at first conception revealed that BCS and BW accounted for 55% of the variation in age at first conception (P < .01).

Animal Feed↗
PubMed2000

Accounting for lactation length and weaning-to-conception interval in genetic evaluations for litter size in swine.

Effects of lactation length and weaning-to-conception interval on the subsequent litter size of purebred sows were estimated using an animal model. Data on 2,847 Landrace sows with 7,125 litters born between January 1989 and May 1997 and on 1,234 Yorkshire sows with 2,999 litters born between January 1990 and May 1997 were obtained from two Canadian selection herds. Sows having a lactation of less than 14 d (MMEW) were usually not mated until their second estrus, whereas sows weaned after at least 14 d of lactation (later weaning) were usually mated on their first estrus. Litter size included both number of pigs born alive and those stillborn. Linear, quadratic, and logarithmic effects of lactation length were tested. The effect of weaning-to-conception interval on litter size was modeled using an approach based on threshold variables and an approach using segmented polynomials. Results indicated linear and logarithmic effects of lactation length on subsequent litter size for Yorkshire and Landrace breeds, respectively. Litter size decreased as weaning-to-conception interval increased up to 7 and 10 d for Yorkshire and Landrace, respectively, then increased with further increases in weaning-to-conception interval up to 35 and 30 d for the two breeds, and then remained constant. The MMEW sows did not have lower subsequent litter sizes than later-weaned sows because the negative effect of a shorter lactation was offset by the positive effect of a longer weaning-to-conception interval. However, average time spent open per parity was longer for MMEW sows than for later-weaned sows. Both lactation length and weaning-to-conception interval should be considered in models for the genetic evaluation of litter size in purebred swine. Segmented polynomials can be used to predict litter size as a continuous function of weaning-to-conception interval or to derive weaning-to-conception interval adjustment factors for litter size.

Animals↗
PubMed1997

Obstetric outcome of natural and assisted conception twin pregnancies is similar.

BACKGROUND: The risk of obstetric intervention and adverse fetal or neonatal outcome is considerably higher in multiple gestation than in singleton pregnancy. How assisted conception influences obstetric management and outcome in twin pregnancies has not been evaluated. METHODS: A survey of all twin pregnancies in Iceland and the Tayside Region, Scotland for a four year period, 1990-93, comparing twins after assisted fertilization with natural conception. RESULTS: The total number of twin pregnancies was 522, of which 453 were natural conceptions and 69 assisted. The twin rate was 1:75 among natural conceptions, but 1:5 in women having assisted fertilization. Mean gestational age in both groups was 36 weeks. Elective Cesarean section was used more often in the assisted conception group (odds ratio 2.57; p = 0.003). Induction rates did not differ to any significant degree and once labor commenced, no difference was seen between assisted and natural conception twins in the mode of delivery or neonatal short term morbidity. Birthweight, gestational length and perinatal mortality rates by conventional and extended classification were not different. CONCLUSION: After allowing for more frequent elective Cesarean section in the obstetric care of the assisted conception pregnancies, there was no major difference in obstetric and neonatal management or outcome between twins resulting from natural and assisted conception.

Adolescent↗
PubMed2004

Effect on gait and socket comfort in unilateral trans-tibial amputees after exchange to a polyurethane concept.

UNLABELLED: Trans-tibial amputees with different indications for amputation often have stump problems. Many active amputees have limits in daily life and sports activities because of pressure ulcers, friction, allergic dermatitis or volume changes. Many methods and materials have been tried to make a well-fitted socket. A new polyurethane concept had been designed with a shock absorbing effect. The purpose of this prospective study was to compare a conventional suspension with a polyurethane concept with regard to the amputees' satisfaction, socket comfort, physical capacity and to analyse the long-term effect. The total material includes 29 unilateral trans-tibial amputees. They answered a questionnaire after 2 months use of the polyurethane concept and were interviewed after 3 and 5 years. After 3 years 22 amputees and after 5 years 20 amputees used the polyurethane concept. Gait was registered in 7 amputees. Speed and symmetry index (SI) for temporal, stride and kinematics variables were used to evaluate gait. The amputees reported that the polyurethane concept was better or much better in physical capacity in 117 (67%) and socket comfort was better or much better in 119 (82%) compared with the conventional suspension. There was no obvious symmetry difference in gait variables in speed, step length, step time or single support or in kinematics knee variables. The amputees tended to walk faster, decrease in symmetry in temporal and stride variables and increase in symmetry in kinematics variables with the polyurethane concept. After 5 years 6 had died and 20 amputees of the surviving 23 used the polyurethane concept. CONCLUSIONS: The polyurethane concept increased comfort considerably and physical activity increased when the trans-tibial amputees changed from conventional suspension. Gait registration was not useful to evaluate the amputees' satisfaction or socket comfort.

Adolescent↗
PubMed1984

Effects of serum treated semen, bulls, and herdsmen-inseminators on conception to first service in large commercial dairy herds.

Semen from each of 10 Holstein bulls was extended to 15 X 10(6) total spermatozoa per dose in egg yolk-Tris and in egg yolk-Tris containing 20% (vol/vol) heat-treated heifer serum. Semen was used during 12 mo by 11 herdsmen-inseminators in four commercial dairy herds to inseminate 2820 Holstein cows on the first postpartum service. Percentage conception of cows free of clinical disorders at breeding was determined by rectal palpation at 30 to 60 days after insemination. Addition of serum to the extender did not influence percentage conception. A significant interaction of bull x seminal treatment was found. Least squares means of percentage conception to first service ranged from 45.3 to 59.9% among the 10 bulls. When bulls were classified as either high (greater than 55%), average (50 to 55%), or low conception (less than 50%), approximately 200 first services were required to classify correctly 80 to 90% of the bulls. Least squares means of conception rates ranged from 40.1 to 62.7% among the 11 herdsmen-inseminators. 1) Addition of heat-treated homologous heifer serum to the extender does not influence conception in a predictable fashion; 2) fertility inherent to the bull significantly influences conception; and 3) inseminator skill affects conception greatly.

Animals↗
PubMed1985

Effects of climatic and management factors on conception rate of dairy cattle in subtropical environment.

Breeding records, representing 12,038 inseminations at Bassett's Dairy Farm (Monticello, FL), were analyzed to document effects of environmental and management factors on fertility of dairy cattle from January 1, 1975 to December 31, 1977. Conception rates of lactating cows decreased sharply when maximum air temperature on day after insemination exceeded 30 degrees C. In contrast, conception rates for heifers did not decline until 35 degrees C. Virgin heifers had higher conception rates for all services (50%) than lactating cows (34%) and suffered only slight depression of fertility during summer months. Heifers required 1.5 services per conception compared with 2.3 for lactating cows. Relationship between conception rate and rainfall on day after insemination was negative and curvilinear. Jerseys had higher conception rates (45%) than Holstein (39%) and Brown Swiss (41%). Services per conception were 1.7, 2.0, and 1.9. Substantial decreases of fertility were associated with advancing service number. Estrous status (standing; positive heat detection patch; mounting activity), inseminator, and year of service were related to variation of conception rate. Seasonal effects on fertility of lactating cows were marked. Thus, environmental management of the postpartum cow during hot summer months is warranted to maximize fertility.

Animal Husbandry↗
PubMed1991

Milk yield variation concurrent with conception.

Milk yield data from herds at the University of Illinois and the University of Wisconsin-Madison were used to characterize milk yield fluctuations concurrent with conception. Analyses were performed on 118 Illinois and 244 Wisconsin cows; milk yields were recorded for 15 d preceding confirmed conception. Conception was confirmed by calving within 11 d of 281 d postbreeding. Each cow's difference between 7-d rolling means for a.m. and p.m. milking yield was subtracted from a.m. yields as a diurnal adjustment. A pattern matching formula that was applied to adjusted yields [( b - a]/a, where a and b were sequential milkings) produced a mean calculated value for the milking nearest conception that was different from all milkings for 15 d preceding conception in Wisconsin data only. Discriminant analysis failed to differentiate between preceding and conception inclusive sequences of adjusted milk yields. Pattern matching formulas applied to individual cow data failed to isolate more than 2% of conceptions when the threshold value was set to eliminate false positives. Results demonstrated low predictive ability for conception using concurrent milk yield fluctuations despite implications of significant mean differences for values that were enhanced by pattern matching formulas.

Animals↗
PubMed2006

Risk factors for delayed conception in Korean dairy herds.

Delayed conception is defined as an interval of greater than 90 days postpartum before a cow becomes pregnant again. In this study, the risk factors for delayed conception in Korean dairy herds were determined by evaluating several reproductive factors in individual cows. The following data was recorded from 1,012 pregnancies in eight dairy herds (designated A-H) from July 2001 to June 2006: herd, cow parity, repeated animal (cows included 2, 3, or more times), calving season, calving condition (abnormal partus), postpartum disorders (retained placenta, metabolic disorders, metritis and ovarian cysts) and conception. Logistic regression was used to evaluate the effects of these factors on delayed conception. A stepwise procedure was used to obtain the appropriate model (alpha = 0.05), which revealed the herd, metritis and ovarian cysts to be significant risk factors for delayed conception. The odds ratio showed that the likelihood of delayed conception increased by 3.3 and 2.0 fold for each incidence of metritis and ovarian cysts, respectively. Delayed conception was significantly more likely in 2 herds, in herd A by 2.0 fold and in herd B by 2.4 fold, compared with herd H. These results suggest that the prevention of postpartum metritis and ovarian cysts, as well as improved herd management, will be needed to maintain a short interval between calving and conception in Korean dairy herds.

Animals↗
PubMed2002

Selective retrieval of pre- and post-coordinated SNOMED concepts.

In general, it is very straightforward to store concept identifiers in electronic medical records and represent them in messages. Information models typically specify the fields that can contain coded entries. For each of these fields there may be additional constraints governing exactly which concept identifiers are applicable. However, because modern terminologies such as SNOMED CT are compositional, allowing concept expressions to be pre-coordinated within the terminology or post-coordinated within the medical record, there remains the potential to express a concept in more than one way. Often times, the various representations are similar, but not equivalent. This paper describes an approach for retrieving these pre- and post-coordinated concept expressions: (1) Create concept expressions using a logically-well-structured terminology (e.g., SNOMED CT) according to the rules of a well-specified information model (in this paper we use the HL7 RIM); (2) Transform pre- and post-coordinated concept expressions into a normalized form; (3) Transform queries into the same normalized form. The normalized instances can then be directly compared to the query. Several implementation considerations have been identified. Transformations into a normal form and execution of queries that require traversal of hierarchies need to be optimized. A detailed understanding of the information model and the terminology model are prerequisites. Queries based on the semantic properties of concepts are only as complete as the semantic information contained in the terminology model. Despite these considerations, the approach appears powerful and will continue to be refined.

Information Storage and Retrieval↗
PubMed2003

Coverage of oncology drug indication concepts and compositional semantics by SNOMED-CT.

OBJECTIVE: To evaluate SNOMED-CT 's ability to represent simple and compositional concepts in FDA approved oncology drug indications. METHODS: Oncology drug indications were decomposed into single and compositional concepts. SNOMED-CT's coverage of single concepts and the semantics needed to create compositional concepts were evaluated using automated and manual techniques. RESULTS: SNOMED-CT covered 86.3% of single concepts present in oncology drug indications; 11.3% of indications were covered completely. Coverage was best for concepts describing diseases, anatomy, and patient characteristics. Medications accounted for 50.5% of missing concepts. Excluding drug names, 45.2% of indications were completely represented. SNOMED-CT's semantics completely represented 60.1% of compositional expressions. CONCLUSIONS: SNOMED-CT's overall coverage of the concepts in oncology drug indications was good. Improvements or alternatives are needed for medications and semantics.

Antineoplastic Agents↗
PubMedDate not supplied

[A study on Korean concepts of relaxation].

Relaxation technique is an independent nursing intervention used in various stressful situations. The concept of relaxation must be explored for the meaning given by the people in their traditional thought and philosophy. Korean relaxation technique, wanting to become culturally acceptable and effective, is learning to recognize and develop Korean concepts, experiences, and musics of relaxation. This study was aimed at discovering Korean concepts, experiences and musics of relaxation and contributing the development of the relaxation technique for Korean people. The subjects were 59 nursing students, 39 hospitalized patients, 61 housewives, 21 rural residents and 16 researchers. Data were collected from September 4th to October 24th, 1991 by interviews or questionnaires. The data analysis was done by qualitative research method, and validity assured by conformation of the concept and category by 2 nursing scientists who had written a Master's thesis on the relaxation technique. The results of the study were summarized as follows; 1. The meaning of the relaxation concept; From 298 statements, 107 concepts were extracted and then 5 categories "Physical domain", "Psychological domain", "Complex domain", "Situation", and "environment" were organized. 'Don't have discomforts, 'don't have muscle tension', 'don't have energy (him in Korean)', 'don't have activities' subcategories were included in "Physical domain". 'Don't have anxiety', 'feel good', 'emotional stability', 'don't have wordly thoughts', 'feel one's brain muddled', 'loss of desire' subcategories were included in "physical domain" 'Comfort body and mind', 'don't have tension of body and mind', 'be sagged' 'liveliness of thoughts' subcategories were included in "Complex domain". 'Rest', 'sleep', 'others' subcategories were included in "Situation domain". And 'quite environment' & 'comfortable environment' subcategories were included in "Environmental domain". 2. The experiences of the relaxation; From 151 statements, 59 experiences were extracted. And then 9 categories--at rest after physical activities, after problem solving, fancy, bathing in the bed, situation, rest, particular time, others--were organized. 3. The musics of the relaxation; From 229 statements, 108 musics were extracted, and the 9 categories--Western classical music, semi classical music, Korean song, Korean popular classical music, song, western popular song, hymn, characteristics of music, others--were organized. In conclusion, There are some differences between Korean concepts, experiences and musics of relaxation and western concepts, experiences and musics of relaxation.

Female↗
PubMed2004

A tool for abstracting relevant classes of concepts: the Common Ancestry Summarizer.

Controlled Medical Terminologies (CMTs) are indispensable tools for present medical information systems and medical informatics researches. Concept-oriented architecture and multiple-hierarchy have been accepted as two of the desiderata of contemporary CMTs. A common problem for informaticians working with class-based methods for terminologies is to find the Most Relevant Common Ancestor (MRCA) for a group of concepts, the common ancestor which has the closest semantic distance to all the given concepts. Finding an ancestor concept to summarize a group of concepts is required to map concepts from the knowledgebase to those of appropriate granularity in CMTs. However, manually exploring the hierarchical relationships and determining the MRCA are daunting tasks due to the massive size, the multiple hierarchies and in some case the cycles of the hierarchical networks of terminologies. In our study, we developed a web-based visualization tool, the Common Ancestry Summarizer (CAS), that graphically displays the hierarchical relations of multiple concepts within CMTs, and also assist users to identify the MRCA of these concepts by identifying the Lowest Common Ancestors (LCAs). The CAS has been shown useful in organizing classes for the controlled terms used in clinical guidelines (e.g. "the bottom-up method").

Algorithms↗
PubMedDate not supplied

Professional and bureaucratic role conceptions and moral behavior among nurses.

This descriptive study tested the relationship between professional and bureaucratic role conceptions and moral behavior. It was theorized that professional-bureaucratic role conceptions of nurses, and their perceptions of the discrepancy between ideal and actual values influence the manner in which they practice and operationalize their professional values, including moral behavior. Data were obtained from 217 practicing nurses representing different positions, areas of practice, education, age, ethnic groups, and work settings. Two of the subscales of Nursing Role Conceptions (Pieta, 1976) were used to measure professional and bureaucratic role conceptions; moral behavior was measured by Judgments About Nursing Decisions (Ketefian, 1981). Professional categorical role conception was positively related to moral behavior. Professional normative role conception and professional role discrepancy were negatively related. Bureaucratic role discrepancy was found to be positively related to moral behavior. Hierarchical multiple regression analyses showed that the combination of professional normative and bureaucratic normative role conceptions, professional categorical and bureaucratic categorical role conceptions, and professional and bureaucratic role discrepancies explained greater variance in moral behavior than either one of the pairs of variables alone. The interactions between these variables were not significant.

Adult↗
PubMed1993

Pregnancy planning and pre-conception counseling. The PRAMS Working Group.

OBJECTIVE: To estimate the percentage of women with one or more of four potentially modifiable risks who could have availed themselves of pre-conception counseling. METHODS: We defined pre-conception counseling to be consultation that occurs shortly before a couple attempts conception. Thus, we assumed that to obtain pre-conception counseling, a woman must plan her pregnancy. We used data from a population-based survey of 12,452 new mothers in four states who delivered babies during 1988-1990. Mothers were contacted 3-6 months after delivery and asked about pre-conception behaviors and the planning status of their pregnancies. We estimated the percentage of women who planned their pregnancies and had an indication for pre-conception counseling related to smoking, drinking, being underweight, or delaying initiation of prenatal care. RESULTS: State-specific response rates ranged from 68-84%. Sixty percent of mothers reported that their pregnancies were planned. In general, mothers with unintended pregnancies were more likely to have an indication for pre-conception counseling than mothers with planned pregnancies. Thirty-eight percent of all mothers planned their pregnancies and had one or more indications for pre-conception counseling. An additional 30% had one or more indications for counseling but did not have a planned pregnancy. CONCLUSIONS: Despite the limited range of indications for counseling that we considered, a substantial percentage of women potentially could have used counseling. A similar percentage of women could have benefited from family planning services.

Adult↗
PubMed1996

[Analysis of the concept of care/caring-structure of attributes identified from qualitative and quantitative research].

The concept of care/caring has been recognized as the central component of nursing in the United States of America since the 1980s. Although caring is the essence and the central focus of clinical nursing, the term has several meanings, and there is no consensus regarding its definition. The concept of care/caring should be examined not only from the nurse's perspective, but also from the patient's perspective. The purpose of this research is to identify the common characteristics of the concept of care/caring from both the patient's and nurse's perspectives, and to clarify the structure of the concept of care/caring in the English articles. Thirty qualitative research papers written by 21 authors and 17 quantitative research papers written by 9 authors were sampled. From the analysis of the 47 articles, 5 categories and 13 sub-categories were identified as attributes of care/caring. The 5 categories were 1) Characteristics of Nurse, 2) Nursing Activities, 3) Patient-Nurse Relationship, 4) Caring Outcomes, and 5) Others. As the next stage of the research, the concept of care/caring in Japanese nursing should be analyzed. It must be determined whether the concept of care/caring is also the central component of nursing in Japan and if so can these identified characteristics of the concept be applied to the concept of care/caring in Japanese nursing.

Attitude of Health Personnel↗
PubMed1998

Autonomy in the rehabilitation of stroke patients in nursing homes. A concept analysis.

This article presents a concept analysis of autonomy in relation to the rehabilitation of stroke patients. Analysis of the results of a literature survey provided three important concepts of autonomy in the field of biomedical ethics: self-governance, self-realization and actual autonomy. These concepts are compared with concepts from caring sciences and summarized in a table. The results indicate the importance of the social environment (formal and informal caregivers) for the restoration of autonomy. Because of the patient's condition and context, a social concept of autonomy makes more sense in the rehabilitation of stroke patients in nursing homes than does an individual concept. The concept analysis sheds light on the fact that the majority of studies regarding patient autonomy are primarily based on theoretical reflections, not on empirical studies. More research is warranted to gather information on how patients themselves consider and appreciate autonomy during rehabilitation, to explore the views of stroke patients' formal and informal caregivers and to investigate whether a social concept of autonomy is suitable for all phases of rehabilitation. Concerning the practice of rehabilitation, no definite conclusion can be given as yet.

Aged↗
PubMed2006

Defining the Bobath concept using the Delphi technique.

BACKGROUND AND PURPOSE: The Bobath concept, based on the work of Berta and Karel Bobath, offers therapists working in the field of neurological rehabilitation a framework for their clinical interventions. It is the most commonly used approach in the UK. Although they recognize that over the last half-century the concept has undergone considerable developments, proponents of the Bobath concept have been criticized for not publishing these changes. The aim of the present study was to use the Delphi technique to enable experts in the field to define the current Bobath concept. METHOD: A four-round Delphi study design was used. The sample included all members of the British Bobath Tutor's Association, who are considered experts in the field. Initial statements were identified from the literature, with respondents generating additional statements during the study. The level of agreement was determined using a five-point Likert scale. The respondents were then provided with feedback on group opinions and given an opportunity to re-rate each statement. The level of group consensus was set at 80%. RESULTS: Fifteen experts took part. The response rate was 85% in the first round, and 93% in each subsequent round. Ten statements from the literature were rated with a further 12 generated by the experts. Thirteen statements achieved consensus for agreement and seven for disagreement. CONCLUSIONS: The Delphi study was an effective research tool, maintaining anonymity of responses and exploring expert opinions on the Bobath concept. The experts stated that Bobath's work has been misunderstood if it is considered as the inhibition of spasticity and the facilitation of normal movement, as described in some literature. They agreed that the Bobath concept was developed by the Bobaths as a living concept, understanding that as therapists' knowledge base grows their view of treatment broadens.

Central Nervous System Diseases↗
PubMed1997

Sexual self-concept and sexual risk-taking.

Data are presented from a postal survey of 474 randomly selected 16-19-year-olds from one U.K. suburban area. A 14-item Sexual Self-Concept Checklist was used to explore the structure of the differences between male and female sexual identities. Two main dimensions in male sexual self-concept emerged: the socio-emotional (romance, sensitivity, eroticism) and the relational (exploitative, seductive, experimental). Female sexual self-concept revolved around concerns with assertiveness (unwillingness to have sex before marriage, controlling when sex occurs, pretending to enjoy sex). Internally reliable scales were constructed for these aspects of the sexual self-concept and were found to relate to both sexual and other forms of risk-taking likely to endanger health. Males with a high relational emphasis in their sexual self-concept were less likely to have had sex and less likely to use alcohol or tobacco. Females with a greater assertiveness score were less likely to be virgins, had had more sexual partners and consumed more alcohol and tobacco. They were not, however, less likely to use condoms. It is concluded that models seeking to explain health behaviours in adolescence should incorporate estimates of the significance of the behaviour for stable aspects of the self-concept. It is further argued that the structure of the sexual self-concept is significantly influenced by dominant social representations of gender differences and relationships. Both identity and social representational processes need to be considered if a comprehensive model of health behaviour is to be evolved.

Adolescent↗