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1.
Brain Res ; 1772: 147666, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34571012

RESUMO

The brain activity changes during infancy that underpin the emergence of functional motor skills, such as reaching and stepping, are not well understood. The current study used functional near-infrared spectroscopy (fNIRS) to examine the hemodynamic response across the frontal, mid-coronal plane (sensorimotor cortex) and external occipital protuberance (cerebellar cortex) regions of typically developing infants (5 to 13 months) during reach-to-grasp or supported treadmill stepping behaviour. Motor ability was assessed using the third edition of the Motor Subscale of the Bayley Scales of Infant Development (BSID-III). Infants with enhanced motor ability demonstrated greater oxy-hemoglobin (HbO) concentration in the contralateral anterior mid-coronal and frontal-dorsal areas during right-handed reach-to-grasp. During bilateral reaching behavior, infants with enhanced motor ability showed greater HbO increases in right frontal-dorsal regions and lower HbO increases in left anterior mid-coronal areas. In contrast, infants' motor ability was associated with changes in de-oxyhemoglobin (HbR) concentration in the ipsilateral anterior mid-coronal, contralateral frontal and left external occipital protuberance regions during left-handed reaching behavior. These relationships between upper limb hemodynamics and infant motor ability are consistent with increased lateralization and cognitive-motor coupling as motor skills emerge. During stepping behavior, infants with enhanced motor ability demonstrated smaller increases in HbR concentration in the bilateral external occipital protuberance region consistent with an emerging efficiency as cruising and independent stepping behavior is still nascent. Together, the current results identify several distinct neural markers of functional motor ability during infancy that may be relevant to diagnostic testing and rehabilitation of developmental movement disorders.


Assuntos
Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Desenvolvimento Infantil/fisiologia , Hemodinâmica/fisiologia , Destreza Motora/fisiologia , Córtex Cerebral/fisiologia , Feminino , Humanos , Lactente , Masculino , Córtex Motor , Oxiemoglobinas/metabolismo , Desempenho Psicomotor/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Córtex Sensório-Motor , Espectroscopia de Luz Próxima ao Infravermelho , Extremidade Superior/irrigação sanguínea , Extremidade Superior/crescimento & desenvolvimento
2.
J Anim Sci ; 95(7): 3003-3011, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727107

RESUMO

The instrument grading assessment portion of the National Beef Quality Audit (NBQA) - 2016 allows the unique opportunity to evaluate beef carcass traits over the course of a year. One week of instrument grading data was collected each month from 5 beef processing corporations encompassing 18 facilities from January 2016 through December 2016 ( = 4,544,635 carcasses). Mean USDA yield grade (YG) was 3.1 with 1.37 cm fat thickness (FT), 88.9 cm LM area, 393.6 kg HCW, and 2.1% KPH. Frequency distribution of USDA YG was 9.5% YG 1, 34.6% YG 2, 38.8% YG 3, 14.6% YG 4, and 2.5% YG 5. Increases in HCW and FT since the NBQA-2011 were major contributors to differences in mean YG and the (numerically) increased frequency of YG 3, 4, and 5 carcasses found in the current audit. Mean marbling score was Small, and the distribution of USDA quality grades was 4.2% Prime, 71.4% Choice, 21.7% Select, and 2.7% other. Frequency of carcasses grading Prime on Monday (6.43%) was numerically higher than the average frequency of carcasses grading Prime overall (4.2%). Monthly HCW means were 397.6 kg in January, 397.2 kg in February, 396.5 kg in March, 389.3 kg in April, 384.8 kg in May, 385.0 kg in June, 386.1 kg in July, 394.1 kg in August, 399.1 kg in September, 403.9 kg in October, 406.5 kg in November, and 401.9 kg in December. Monthly mean marbling scores were Small in January, Small in February, Small in March, Small in April, Small in May, Small in June, Small in July, Small in August, Small in September, Small in October, Small in November, and Small in December. Both mean HCW and mean marbling score declined in the months of May and June. The month with the greatest numerical frequency of dark cutters was October (0.74%). Comparison of overall data from in-plant carcass and instrument grading assessments revealed close alignment of information, especially for YG (3.1 for in-plant assessment versus 3.1 for instrument grading) and marbling (Small for in-plant assessment versus Small for instrument grading). These findings allow the beef industry access to the greatest volume of beef value-determining characteristics for the U.S. fed steer and heifer population than ever reported, resulting in potentially more precise targeting of future quality and consistency efforts.


Assuntos
Bovinos/fisiologia , Carne Vermelha/normas , Animais , Composição Corporal , Bovinos/crescimento & desenvolvimento , Feminino , Masculino , Inquéritos e Questionários , Estados Unidos
3.
J Anim Sci ; 95(7): 2993-3002, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727109

RESUMO

The National Beef Quality Audit (NBQA)-2016 used in-plant cooler assessments to benchmark the current status of the fed steer and heifer beef industry in the United States. In-plant cooler assessments ( = 9,106 carcasses) were conducted at 30 facilities, where approximately 10% of a single day's production were evaluated for USDA quality grade (QG) and yield grade (YG) factors. Frequencies of evaluated traits were 66.5% steer and 33.4% heifer sex classes and 82.9% native, 15.9% dairy-type, and 1.2% estimated breed types. Mean USDA YG factors were 1.42 cm for adjusted fat thickness, 89.5 cm for LM area, 390.3 kg for HCW, and 1.9% for KPH. Mean USDA YG was 3.1, with a frequency distribution of 9.6% YG 1, 36.7% YG 2, 39.2% YG 3, 12.0% YG 4, and 2.5% YG 5. Mean USDA QG traits were Small for marbling score, A for overall maturity, A55 for lean maturity, and A for skeletal maturity. Mean USDA QG was Select with a frequency distribution of QG of 3.8% Prime, 67.3% Choice, 23.2% Select, and 5.6% lower score. Lower score included dark cutter (1.9%), blood splash (0.1%), and hard bone, which are USDA overall maturity scores of C or older (1.8%). Marbling score distributions were 0.85% Slightly Abundant or greater, 7.63% Moderate, 23.54% Modest, 39.63% Small, 23.62% Slight, and 0.83% Traces or less. Carcasses that were Choice or Select and USDA YG 2 or 3 accounted for 70.7% of the carcasses evaluated. Compared with the previous NBQA, we found a numerical increase in mean USDA YG, USDA QG, adjusted fat thickness, HCW, LM area, and marbling score with an increase in dairy-type carcasses and percentage of carcasses grading USDA Prime and Choice as well as frequency of USDA YG 4 and 5. The findings from this study will be used by all segments of the industry to understand and improve the quality of fed steer and heifer beef that is being produced.


Assuntos
Bovinos/fisiologia , Carne Vermelha/normas , Animais , Composição Corporal , Cruzamento , Bovinos/crescimento & desenvolvimento , Feminino , Masculino , Inquéritos e Questionários , Estados Unidos
4.
Transl Anim Sci ; 1(2): 229-238, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32704647

RESUMO

The National Beef Quality Audit-2016 (NBQA-2016) was conducted to assess current transportation, mobility, and quality characteristics of U.S. fed steers and heifers. Data were collected at 17 beef processing facilities between March and November 2016. About 8,000 live cattle were evaluated for transportation and mobility, and about 25,000 carcasses were evaluated on the slaughter floor. Cattle were in transit to the slaughter facility for a mean duration of 2.7 h from a mean distance of 218.5 km using trailers with dimensions ranging from 17.84 m2 to 59.09 m2. Area allotted per animal averaged 1.13 m2 and ranged from 0.85 m2 to 2.28 m2. A total of 96.8% of cattle received a mobility score of 1 (walks easily, no apparent lameness). Identification types (35.1% had multiple) were lot visual tags (61.5%), individual tags (55.0%), electronic tags (16.9%), metal-clip tags (9.2%), bar-coded tags (0.05%), wattles (0.01%), and other (2.6%). Cattle were black-hided (57.8%), Holstein (20.4%), red-hided (10.5%), yellow-hided (4.8%), gray-hided (2.9%), brown-hided (1.3%), and white-hided (1.1%). Unbranded hides were observed on 74.3% of cattle; 18.6% had brands located on the butt, 6.3% on the side, and 1.3% on the shoulder (values exceed 100% due to multiple brands). For hide-on carcasses, 37.7% displayed no mud or manure; specific locations for mud or manure were legs (40.8%), belly (33.0%), tail region (15.5%), side (6.8%), and top-line (3.9%). Cattle without horns represented 83.3% of the sample, and cattle that did have horns measured: < 2.54 cm (5.5%), 2.54 to 12.7 cm (8.3%), and > 12.7 cm (2.9%). Carcasses without bruises represented 61.1% of those sampled, whereas 28.2% had 1, 8.2% had 2, 2.1% had 3, and 0.3% had 4 bruises. Of those carcasses with a bruise, the bruise was located on the loin (29.7%), round (27.8%), chuck (16.4%), rib (14.4%), and brisket/plate/flank (11.6%). Frequencies of offal condemnations were livers (30.8%), lungs (18.2%), viscera (16.3%), hearts (11.1%), heads (2.7%), and tongues (2.0%). Compared to NBQA-2011, fewer cattle were identified for traceability, fewer were black-hided, a greater number were Holstein cattle, more with no brand and no horns, fewer without bruises, more liver, lung, and viscera condemnations, and fewer heads and tongues were condemned. The NBQA remains an influential survey for the U.S. beef industry to provide benchmarks and strategic plans for continued improvement of beef quality and consistency.

5.
Transl Anim Sci ; 1(4): 570-584, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32704679

RESUMO

The National Beef Quality Audit-2016 marks the fourth iteration in a series assessing the quality of live beef and dairy cows and bulls and their carcass counterparts. The objective was to determine the incidence of producer-related defects, and report cattle and carcass traits associated with producer management. Conducted from March through December of 2016, trailers (n = 154), live animals (n = 5,470), hide-on carcasses (n = 5,278), and hide-off hot carcasses (n = 5,510) were surveyed in 18 commercial packing facilities throughout the United States. Cattle were allowed 2.3 m2 of trailer space on average during transit indicating some haulers are adhering to industry handling guidelines for trailer space requirements. Of the mixed gender loads arriving at processing facilities, cows and bulls were not segregated on 64.4% of the trailers surveyed. When assessed for mobility, the greatest majority of cattle surveyed were sound. Since the inception of the quality audit series, beef cows have shown substantial improvements in muscle. Today over 90.0% of dairy cows are too light muscled. The mean body condition score for beef animals was 4.7 and for dairy cows and bulls was 2.6 and 3.3, respectively. Dairy cattle were lighter muscled, yet fatter than the dairy cattle surveyed in 2007. Of cattle surveyed, most did not have horns, nor any visible live animal defects. Unbranded hides were observed on 77.3% of cattle. Carcass bruising was seen on 64.1% of cow carcasses and 42.9% of bull carcasses. However, over half of all bruises were identified to only be minor in severity. Nearly all cattle (98.4%) were free of visible injection-site lesions. Current results suggest improvements have been made in cattle and meat quality in the cow and bull sector. Furthermore, the results provide guidance for continued educational and research efforts for improving market cow and bull beef quality.

6.
Environ Entomol ; 42(5): 942-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24331605

RESUMO

Acrobasis nuxvorella Neunzig (pecan nut casebearer) is a monophagous herbivore of Carya illinoinensis (Wang.) K. Koch (pecan); both are indigenous to North America, where Carya has evolved for ≈60 million years. We hypothesized that this close association may have resulted in a parallel evolution allowing casebearer to use pecan volatiles to synchronize seasonality. Casebearer overwinters in diapause as a first-instar larva in a hibernaculum attached to a dormant pecan bud. Larval emergence from this structure after diapause or postdiapause quiescence coincides with the onset of pecan bud growth in the spring, and this interaction was the subject of this study. Dormant pecan twigs with hibernacula-infested buds were exposed to a water control or pecan volatiles from 'Western Schley' cultivar, and monitored to observe larval response by using a microcalorimeter. Initial testing showed that metabolic heat produced by overwintering larvae remained low and unchanged when exposed to water vapor and significantly increased within a few hours after exposure to volatiles from new pecan foliage. This shows that these larvae in hibernacula are in a physiologically suppressed state of diapause or postdiapause quiescence, from which they detect and respond to these pecan volatiles. Further studies to quantify larval responses showed that 90 and 80% of the larvae became active and emerged from their hibernacula ≈6 d after exposure to Western Schley and 'Wichita' volatiles, respectively. Mixtures of 13 sesquiterpenes from those pecan volatiles were identified to induce physiological activity within larvae after hours of exposure, followed some days later by larval emergence from hibernacula. Host volatiles, to our knowledge, have not previously been reported to induce early instar larvae in hibernacula to rouse from a state of physiological arrest to resume normal growth and development. This also has potential for use in pest management.


Assuntos
Carya/metabolismo , Diapausa de Inseto , Mariposas/crescimento & desenvolvimento , Feromônios/metabolismo , Animais , Larva/crescimento & desenvolvimento , Controle Biológico de Vetores , Estações do Ano
7.
Ecotoxicology ; 22(3): 528-37, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23455995

RESUMO

Spiders are a principal arthropod group that preys on numerous pests of vegetables and other crops. In this study, we determined the effects of the two most commonly used insecticides, spinosad and λ-cyhalothrin, on diversity of spiders on cabbage in south Texas. In two seasons (fall 2008 and spring 2009), we collected a total of 588 spiders belonging to 53 species in 11 families from spinosad and λ-cyhalothrin-treated cabbages and the untreated control plants. A great majority of spiders were collected from the pitfall traps (554) where only a few (34) were collected from the blower/vacuum sampling. In the insecticide-treated plots, there were significantly fewer spider individuals, species and families than in untreated fields. Spinosad had significantly less effect on spiders in total individuals, number of species and families than λ-cyhalothrin. The effects of the two insecticides were further demonstrated by the Shannon-Weiner index (H') and the hierarchical richness index (HRI). Spider diversity in the spinosad-treated plots were not significantly different from that in the untreated fields but were greater than those in λ-cyhalothrin-treated plots in both seasons when measured by H' values. In contrast, the H' values of spider's diversity in the λ-cyhalothrin-treated plots were significantly lower than spinosad-treated and untreated plots. High values of HRI for spider richness in the spinosad-treated plots suggested that spinosad had less effect on spiders than λ-cyhalothrin. We concluded that spinosad was more compatible with spiders on cabbage compared to λ-cyhalothrin and that this information should be used when developing insecticide resistance management strategies.


Assuntos
Inseticidas/toxicidade , Macrolídeos/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Aranhas/efeitos dos fármacos , Animais , Conservação dos Recursos Naturais , Combinação de Medicamentos , Densidade Demográfica , Dinâmica Populacional , Especificidade da Espécie , Texas
8.
Environ Entomol ; 40(4): 889-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22251690

RESUMO

Two synthetic sex pheromones have been developed and are currently used to detect the flight of the pecan nut casebearer, Acrobasis nuxvorella Neunzig, the most damaging pest of pecan [Carya illinoinensis (Wangenh.) K. Koch]. One pheromone (referred to as standard) is attractive to moths in the southern United States, but not in Mexico. The other pheromone (referred to as Mexican) is attractive to moths in the southern United States and in Mexico. These two pheromones have been implemented by producers as an important tool in monitoring the activity of this pest and have allowed for more efficient pesticide use. In the future, these pheromones could be used as a means of population reduction through pheromone based control methods. Trapping data taken over a 3-yr period were used to determine if phenological differences exist between pheromone types of pecan nut casebearer. The relative abundance of each pheromone type at several locations in the United States also was evaluated. Results of this study indicate that no phenological differences exist between the two pheromone types studied in the United States and that significantly more males are attracted to field-deployed pheromone traps baited with the standard pheromone than to traps baited with the Mexican pheromone.


Assuntos
Carya/parasitologia , Voo Animal , Mariposas/fisiologia , Feromônios/fisiologia , Análise de Variância , Animais , Feminino , Masculino , Densidade Demográfica , Estados Unidos
9.
Mult Scler ; 16(7): 801-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20621951

RESUMO

BACKGROUND: Interferon-beta1b (IFN-beta1b), an effective treatment for multiple sclerosis (MS), lessens disease severity in MS patients. However, the mechanisms of its immunoregulatory and anti-inflammatory effects in MS remain only partially understood. Matrix metalloproteinases (MMP) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) are involved in blood brain barrier disruption and formation of MS lesions. Th1/Th17 cytokines e.g. interleukins IL-12p40, IL-17, and IL-23, are associated with MS disease activity and are significant players in pathogenesis of MS. OBJECTIVE: During a 1-year prospective study, we serially measured serum MMP-8, MMP-9, TIMP-1, IL-12p40, IL-17, and IL-23 in 24 patients with relapsing-remitting MS. We compared the results to clinical course and to brain magnetic resonance imaging. IFN-beta1b decreased serum MMP-8 and MMP-9 (not TIMP-1). RESULTS: The sustained treatment with IFN-beta1b attenuated the pro-inflammatory environment by significantly reducing the serum IL-12p40, IL-23, and showed a trend for decreasing IL-17. Decreased serum MMP-8, MMP-9, IL-12 and IL-23 levels were correlated with a decrease in the number of contrast-enhanced T2-weighted lesions. CONCLUSION: Early treatment of MS with IFN-beta1b may stabilize clinical disease by attenuating levels of inflammatory cytokines and MMPs. Serial measurement of inflammatory mediators may serve as sensitive markers to gauge therapeutic responses to IFN-beta1b during the first year of treatment.


Assuntos
Fatores Imunológicos/uso terapêutico , Interferon beta/uso terapêutico , Subunidade p40 da Interleucina-12/sangue , Interleucina-23/sangue , Metaloproteinase 8 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon beta-1b , Interleucina-17/sangue , Louisiana , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla Recidivante-Remitente/enzimologia , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/patologia , Estudos Prospectivos , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/sangue , Resultado do Tratamento , Adulto Jovem
10.
Environ Entomol ; 39(5): 1593-600, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22546457

RESUMO

Multiple species of Pseudacteon phorid flies (Diptera: Phoridae) are currently being released throughout the southern United States to aid biological control of red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae). It is anticipated that these flies will interfere with S. invicta foraging, allowing native ant assemblages to outcompete S. invicta for available resources. Numerous studies have shown a decrease in S. invicta foraging intensity when exposed to phorids. This study documents a behavioral change in phorid-exposed S. invicta colonies at a phorid release site in central Texas. Significant differences in forager size ratios were detected between phorid-exposed and phorid-absent colonies. A similar phenomenon was recently documented in the native range of these insects in South America as well. Experimental manipulation of ratios of S. invicta worker sizes has been shown to have important effects on colony success. This newly documented phorid-mediated S. invicta colony-level effect represents a significant shift in S. invicta foraging dynamics and may provide an additional mechanism by which phorids can influence S. invicta populations in their United States range.


Assuntos
Formigas/parasitologia , Dípteros/fisiologia , Controle Biológico de Vetores , Animais , Formigas/anatomia & histologia , Formigas/fisiologia , Agentes de Controle Biológico , Demografia , Comportamento Alimentar , Texas
11.
J Econ Entomol ; 94(1): 180-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11233111

RESUMO

A range of infestation levels of the whitefly Bemisia argentifolii Bellows & Perring were established across experimental field plots of cantaloupe by varying insecticide treatments to evaluate the relationships between whitefly density and crop yield and quality. High levels of whitefly adults and immatures were associated with significant reductions in fruit yield, a decrease in fruit size, and an increase in the percentage of fruits with sooty mold. Yield loss rates (kg/ha/adult or nymph) decreased in a nonlinear fashion with increasing whitefly numbers. Estimated economic injury levels varied as a function of whitefly density, whitefly stage, control cost, crop cultivar, and crop season. Estimates of economic injury levels for one ($31.2/ha), five ($156/ha), and 10 ($312/ha) insecticide treatments ranged from 0.02 to 0.39, from 0.12 to 1.96, and from 0.24 to 3.92 adults/leaf, and from 0.20 to 5.43, from 0.98 to 27.17, and from 1.97 to 54.35 nymphs/6.45 cm2, respectively.


Assuntos
Produtos Agrícolas/economia , Frutas , Hemípteros , Animais , Frutas/parasitologia , Densidade Demográfica
12.
Soc Sci Res ; 29(3): 356-81, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14653265

RESUMO

This paper examines the quality and comparability of child care data obtained from eight waves of data from four nationally representative data sources: the National Longitudinal Survey of Youth (1986 and 1988), the Survey of Income and Program Participation (1986, 1987, 1988, and 1990), the National Child Care Survey, and the National Survey of Families and Households. We examine whether different study designs and survey techniques for asking questions about child care produce similar results on both the levels and determinants of child care. We identified four main sources of difference in the data sets that could impact the quality and comparability of child care research: when the interview is conducted; screening questions used to determine who is asked about child care; the population of parents and children represented in the survey; and the way child care questions are asked. Our findings indicate that summer interviews and screening on mother's work status produce the largest differences in the levels and effects of child care across these studies. Even after removing the effects of summer interviews and screening questions, however, substantial differences exist across the studies.


Assuntos
Cuidado da Criança/história , Inquéritos Epidemiológicos , Estatística como Assunto/história , Criança , Pré-Escolar , História do Século XX , Humanos , Estados Unidos
13.
Science ; 273(5282): 1641b-2b, 1996 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-17835031
15.
Science ; 213(4512): 1057, 1981 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-17741076
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