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1.
Chem Rev ; 119(14): 8262-8290, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30707011

RESUMO

Classically closo-carborane anions, particularly [HCB11H11]- and [HCB9H9]-, and their derivatives have primarily been used as weakly coordinating anions to isolate reactive intermediates, platforms for stoichiometric and catalytic functionalization, counteranions for simple Lewis acid catalysis, and components of materials like liquid crystals. The aim of this article is to educate the reader on the contemporary nonclassical applications of these anions. Specifically, this review will cover new directions in main group catalysis utilized to achieve some of the most challenging catalytic reactions such as C-F, C-H, and C-C functionalizations that are difficult or impossible to realize with transition metals. In addition, the review will cover the utilization of the clusters as dianionic C σ-bound ligands for coordination chemistry, ligand substituents for coordination chemistry and advanced catalyst design, and covalently bound spectator substituents to stabilize radicals. Furthermore, their applications as solution-based and solid-state electrolytes for Li, Na, and Mg batteries will be discussed.

2.
Reprod Domest Anim ; 49(6): 1063-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25293406

RESUMO

Profitability of a beef operation is determined by the proportion of cows attaining pregnancy early in the breeding season and those that are pregnant at the end of breeding season. Many factors, including temperament, contribute to those reproductive parameters. The objective of this study was to evaluate effects of temperament on reproductive performance of beef cows. In Experiment 1, Angus and Angus-cross beef cows (n = 1546) from eight locations were assigned a body condition score (BCS; 1 = emaciated; 9 = obese) and chute exit and gait score (1 = slow exit, walk; calm temperament; 2 = jump, trot or run; excitable temperament). Cows were grouped with bulls (1 : 25 to 1 : 30; with satisfactory breeding potential and free of venereal disease) for an 85-day breeding season. Pregnancy status and stage of gestation were determined (transrectal palpation) 35 days after the end of the breeding season. Controlling for BCS (p < 0.01) and handling facility (p < 0.0001) and handling facility by temperament score interaction (p < 0.001), breeding season pregnancy rate was lower in excited versus calm cows [88.6% (798/901) vs 94.1% (607/645); p < 0.001]. Cows with an excitable temperament took 24 more days to become pregnant compared to calm cows (median days to pregnancy, 35 vs 59 days; p < 0.0001). In Experiment 2, Angus and Angus-cross beef cows (n = 1407) from 8 locations were assigned scores for body condition and chute exit and gait (as described in Experiment 1) and assigned to bulls (breeding sound and free of venereal disease; 1 : 25 to 1 : 30) for 85 days. Pregnancy status was determined by transrectal palpation at 2 and 6 months after the onset of the breeding season. Controlling for BCS (p < 0.05), pregnancy loss was higher in excited versus calm cows [5.5% (36/651) vs 3.2% (20/623), p < 0.0001]. In conclusion, beef cows with an excitable temperament had significantly lower reproductive performance than calmer cows. The modified two-point chute exit-gait scoring method was repeatable and identified cattle with an excitable temperament.


Assuntos
Comportamento Animal , Bovinos/fisiologia , Reprodução/fisiologia , Temperamento/fisiologia , Animais , Composição Corporal , Feminino , Gravidez , Estresse Fisiológico
3.
Theriogenology ; 77(8): 1624-31, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22289222

RESUMO

The objective was to determine whether timed artificial insemination (TAI) 56 h after removal of a Controlled Internal Drug Release (CIDR, 1.38 g of progesterone) insert would improve AI pregnancy rate in beef heifers compared to TAI 72 h after CIDR insert removal in a 5-days CO-Synch + CIDR protocol. Angus cross beef heifers (n = 1098) at nine locations [WA (5 locations; n = 634), ID (2 locations; n = 211), VA (one location; n = 193) and WY (one location; n = 60)] were included in this study. All heifers were given a body condition score (BCS; 1-emaciated; 9-obese), and received a CIDR insert and 100 µg of gonadorelin hydrochloride (GnRH) on Day 0. The CIDR insert was removed and two doses of 25 mg of dinoprost (PGF(2α)) were given, first dose at CIDR insert removal and second dose 6 h later, on Day 5. A subset of heifers (n = 629) received an estrus detector aid at CIDR removal. After CIDR removal, heifers were observed thrice daily for estrus and estrus detector aid status until they were inseminated. Within farm, heifers were randomly allocated to two groups and were inseminated either at 56 h (n = 554) or at 72 h (n = 544) after CIDR removal. All heifers were given 100 µg of GnRH at AI. Insemination 56 h after CIDR insert removal improved AI pregnancy rate compared to insemination 72 h (66.2 vs. 55.9%; P < 0.001; 1 - ß = 0.94). Locations, BCS categories (≤ 6 vs. > 6) and location by treatment and BCS by treatment interactions did not influence AI pregnancy rate (P > 0.1). The AI pregnancy rates for heifers with BCS ≤ 6 and > 6 were 61.8 and 60.1%, respectively (P > 0.1). The AI pregnancy rates among locations varied from 54.9 to 69.2% (P > 0.1). The AI pregnancy rate for heifers observed in estrus at or before AI was not different compared to heifers not observed in estrus [(65.4% (302/462) vs. 52.7% (88/167); P > 0.05)]. In conclusion, heifers inseminated 56 h after CIDR insert removal in a 5-days CO-Synch + CIDR protocol had, on average, 10.3% higher AI pregnancy rate compared to heifers inseminated 72 h after CIDR insert removal.


Assuntos
Bovinos/fisiologia , Inseminação Artificial/veterinária , Taxa de Gravidez , Progesterona/administração & dosagem , Administração Intravaginal , Animais , Preparações de Ação Retardada/administração & dosagem , Sincronização do Estro/métodos , Feminino , Inseminação Artificial/métodos , Gravidez , Fatores de Tempo
4.
Adolescence ; 30(119): 677-83, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7484351

RESUMO

Nurses employed by schools and health departments have varying responsibilities for curricula related to menstruation, menarche, and sexuality. Nevertheless, the school nurse is usually a source of information on these subjects whether employed full-time in school health or also participating in other nursing roles in the community. This survey examines the involvement of school nurses in curricula related to human reproduction including contraception. Data about their involvement in these classroom topics provides a basis for evaluating their roles and making recommendations for subsequent continuing education programs for school health nurses.


Assuntos
Atitude do Pessoal de Saúde , Currículo , Serviços de Enfermagem Escolar , Educação Sexual/organização & administração , Adolescente , Criança , Anticoncepcionais , Educação Continuada em Enfermagem , Feminino , Humanos , Masculino , Menstruação/fisiologia , Pais , Reprodução/fisiologia , Serviços de Saúde Escolar/organização & administração , Serviços de Enfermagem Escolar/educação
5.
J Sch Health ; 63(10): 417-20, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8133644

RESUMO

In January 1991, 135 school districts and six specialty schools in North Carolina were surveyed to obtain data regarding the performance of specific health-related procedures in the school setting. Results indicate a patchwork approach to meeting the special health care needs of these children, and that a variety of school personnel as well as parents and health professionals are involved in coordinating and performing the procedures. Teachers and teacher assistants perform these health-related procedures 44% of the time. Registered nurses coordinate the care, including assessment, care planning, and supervision to assure continued competence of the care provider and safety for the student less than 45% of the time. Some 13 school districts reported having no school nurse services. Efforts have begun to legislate a statewide policy with appropriations for a registered nurse to provide an initial evaluation of the student's needs, develop care plan, and provide ongoing supervision of services to assure that safe, appropriate care is being provided to all students with special health-related needs in North Carolina.


Assuntos
Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Serviços de Saúde Escolar/estatística & dados numéricos , Adolescente , Criança , Humanos , North Carolina , Pais , Serviços de Enfermagem Escolar/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Ensino/estatística & dados numéricos
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