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1.
J Chem Phys ; 146(5): 052807, 2017 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-28178831

RESUMEN

We investigated the growth of the two phase-separating materials diindenoperylene (DIP) and buckminsterfullerene C60 with different mixing ratio in real-time and in situ by X-ray scattering experiments. We found that at room temperature, mixtures with an excess of DIP show a growth mode which is very close to the perfect layer-by-layer limit with DIP crystallites forming over the entire film thickness. An unexpected increase in the island size is observed for these mixtures as a function of film thickness. On the other hand, equimolar and C60 dominated mixtures grow with poor crystallinity but form very smooth films. Additionally, it is observed that higher substrate temperatures lead to an increase in the length scale of phase separation with film thickness.

2.
Poult Sci ; 103(11): 104163, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39153269

RESUMEN

Objective, robust, and repeatable assessments of fear responses of poultry can lead to improvements in research techniques, the validity of test results, and ultimately bird welfare. The objective of this study was to examine the effect of 2 different holding methods on broiler fear responses during the inversion test, a standardized method of assessing fear in poultry. On D15 and D34 mixed-sex broilers (N = 80) were inverted and held either by their shanks (N = 40) or feet (N = 40) at arm's length away from the experimenter for 30 s. The frequency of wing flapping, head movement, attempts to right, and vocalizations were observed from video recordings collected during the inversion test. Vocalizations at D15 and D34 were not different when comparing holding methods. Frequency of attempts to right and wing flapping at D15 were greater (P < 0.001) for birds held by their feet (0.90 and 16.6, respectively) than when they were held by their shanks (0.20 and 0.73, respectively). Similarly, on D34 wing flapping remained greater (P < 0.001) for birds held by their feet (23.8) compared to their shanks (8.1). Conversely, head movements were greater (P = 0.05) for birds held by their shanks (9.2) compared to their feet (6.3) on D15. Within both the shank and feet holding method, vocalizations at D15 were greater (30.7 and 35.6, respectively) compared to D34 (11.93 and 15.38, respectively) (P < 0.001). There was no holding method effect on head movements within each age. These results suggest that behaviors observed during the inversion test can be influenced by the inversion holding method and that handling should be standardized while conducting behavioral tests to assess fear in poultry.


Asunto(s)
Pollos , Animales , Pollos/fisiología , Masculino , Femenino , Miedo , Crianza de Animales Domésticos/métodos , Bienestar del Animal , Conducta Animal/fisiología
3.
Poult Sci ; 102(1): 102245, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36335739

RESUMEN

The skeletal integrity of chickens is an important area of research and detailed measures are needed to better understand the influence of experimental manipulation on bone health. The objective of this experiment was to compare 2 methods to measure the superficial tibiotarsus (tibia) morphology of broiler chickens collected in the wet laboratory (WL) or from digital images (DIG). The length, width at 90%, 75%, 50%, 25%, and 10% of the length, proximal and distal head width, medial, lateral, and distal intercondylar groove depth (ID), and proximal head angle were measured on the right and left tibias collected from broilers in 2 experiments (E1, E2). In both experiments, tibias had a greater width at 90% of the length when measured with the WL method compared with the DIG method (P ≤ 0.04), while tibias measured with the DIG method had a greater length, distal ID, and widths at 10%, 25%, 50%, and 75%, of the length compared with the WL method (P < 0.0001). In E1, tibias measured with the DIG method had a greater medial, lateral, and distal ID compared with the WL method (P ≤ 0.04). In E2, compared with the DIG method, tibias measured with the WL method had a greater distal head width and lateral ID, yet a shallower distal ID (P ≤ 0.03). The use of the DIG method provided more precise measures but, due to the limitations of measures from digital images and the opportunity for more accurate measures to be collected with the WL method, the WL method is recommended to measure the superficial morphology of broiler chickens because it was more accessible and practical.


Asunto(s)
Pollos , Tibia , Animales , Tibia/anatomía & histología , Pollos/anatomía & histología
4.
Poult Sci ; 102(1): 102233, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36351344

RESUMEN

Providing environmental enrichments that increase environmental complexity can benefit poultry welfare. This Poultry Science Association symposium paper is structured around four themes on 1) poultry preferences and affective states 2) species-specific behavior, including play behavior and the relationship between behavior, activity level and walking ability, 3) environmental enrichment and its relationship with indicators of welfare, and 4) a case study focusing on the application of enrichments in commercial broiler chicken production. For effective enrichment strategies, the birds' perspective matters most, and we need to consider individual variation, social dynamics, and previous experience when assessing these strategies. Play behavior can be a valuable indicator of positive affect, and while we do not yet know how much play would be optimal, absence of play suggests a welfare deficit. Activity levels and behavior can be improved by environmental modifications and prior research has shown that the activity level of broilers can be increased, at least temporarily, by increasing the environmental complexity. However, more research on impacts of enrichments on birds' resilience, on birds in commercial conditions, and on slow(er)-growing strains is needed. Finally, incorporating farmers' expertise can greatly benefit enrichment design and implementation on commercial farms.


Asunto(s)
Bienestar del Animal , Pollos , Aves de Corral , Animales , Bienestar del Animal/normas , Vivienda para Animales , Calidad de Vida , Juego e Implementos de Juego
5.
Poult Sci ; 101(6): 101833, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35421814

RESUMEN

The fast growth rate of broiler chickens is a welfare concern that has increased consumer interest in chicken from slower growing (SG) broilers. Replacing conventional (CONV) broilers with SG broilers will reduce chicken supply and SG broilers require different management practices than CONV. This study evaluated the effects of 2 stocking densities on the carcass composition and meat quality of CONV broilers that reach market weight at 42 d and SG broilers that reach market weight at 63 d. Male broilers from each strain were exclusively stocked into 16 pens at a density of either 29 kg/m2 or 37 kg/m2. Live body, carcass without giblets (WOG), and part weights were recorded and used to calculate yield. Initial and 24-hour pH, color (L*, a*, and b*), cooking loss, and Warner Bratzler shear force of the breast and thigh muscles were measured. Birds from both strains reached similar live body and carcass WOG weights. CONV had 3.4%, 13.0%, and 2.8% greater (P ≤ 0.002), carcass WOG, breast, and tenderloin yields, while SG had 2.7%, 5.0%, 7.5%, and 1.2% greater (P < 0.0001) wings, leg quarters, frame, and skin yields, respectively. CONV breast 24-h pH and cooking loss were greater (P ≤ 0.04) than SG. While SG thigh shear force was greater than CONV (P = 0.008), breast shear force was the lowest for CONV stocked at 29 kg/m2 and the greatest for SG stocked at 37 kg/m2 (P = 0.04). SG had a paler breast than CONV, while CONV had a yellower breast than SG (P < 0.0001). While SG had a redder thigh than CONV (P = 0.002), SG stocked at 29 kg/m2 had a redder breast than SG stocked at 37 kg/m2, with both CONV groups intermediate (P = 0.04). These results indicate that differences in male broiler meat quality were affected more by strain than by stocking density. Compared with CONV, SG broiler meat quality was more affected by stocking density in this study.


Asunto(s)
Pollos , Carne , Animales , Pollos/fisiología , Culinaria , Masculino , Carne/análisis , Músculo Esquelético/fisiología
6.
Poult Sci ; 102(1): 102305, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36603238

RESUMEN

Antimicrobial resistance is a threat to animal and human health. As a commensal and zoonotic bacterium, Escherichia coli has the potential to be a pathogenic source of antimicrobial resistance. The purpose of this study aimed to investigate the antimicrobial resistance profile of E. coli isolated from litter collected from pens in a broiler chicken experiment. E. coli was isolated from litter samples (n = 68 isolates) of 16 pens housing broilers to d 53 of age. Resistance to 10 antimicrobials was observed by disc diffusion. The presence of 23 antimicrobial and heavy metal resistance genes, O serogroups, and avian pathogenic E. coli (APEC-like) minimal predictor genes were identified through PCR. E. coli isolates presented the greatest resistance to cephalothin (54.4%), tetracycline (27.9%), streptomycin (29.4%), ampicillin (20.6%), colistin (13.2%), sulphonamides (8.8%), and imipenem (1.5%). Multidrug resistance to at least 3 antimicrobials was observed in 22.1% of isolates. The identified O-types of the E. coli isolates were O15, O75, O78, and O91. There was a greater likelihood that the genes groEL, aph(3)IA, silP, sull, aadA, qacEdelta1, iroN, ompTp, and hlyF were present in isolates that exhibited ampicillin resistance (P ≤ 0.05). There was a greater likelihood that the groEL gene was present in isolates resistant to ampicillin, colistin, tetracycline, sulphonamides, or cephalothin (P ≤ 0.05). Further characterizing E. coli antimicrobial resistance is essential and aids in developing effective solutions, thereby furthering the One Health objective.

7.
Poult Sci ; 100(5): 101054, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33744614

RESUMEN

Footpad dermatitis (FPD), damage and inflammation of the plantar surface of the foot, is of concern for poultry because FPD affects the birds' welfare and production value. Footpad dermatitis is painful and causes costly chicken paw downgrades, carcass condemnations, and reduced live weights. However, a universal preventative has not been found. The hypothesis was that diets containing orange corn, when compared with diets containing yellow or white corn, would reduce the severity of footpad dermatitis in broiler chickens on wet litter. When compared with yellow and white corn, orange corn contains higher quantities of carotenoids, antioxidant pigments, believed to play a role in skin and feather health. This experiment was a randomized block, 3 × 2 factorial design: orange, yellow, and white corn diets with birds raised on wet or dry litter (control group). Female Ross 708 broilers (n = 960) were used to create 4 replicates of each diet x litter treatment combination. Footpads were scored at day 19, 27, 35, and 42, following the Global Animal Partnership standard's 0-2 scale of visual increasing severity: 0 indicates minimal damage and 1 and 2 indicate mild to severe lesions and ulceration, dark papillae, and/or bumble foot. At 42 d of age, birds on the wet litter had greater severity of FPD, scores 1 and 2, compared with the control group (88 vs. 13% respectively; P < 0.0001). At 42 d of age, prevalence of more severe footpad scores, 1 or 2, was lowest on the orange corn diet (33%), followed by white corn (56%) and yellow corn (63%). Birds fed the orange corn diet had higher BW throughout the study (P = 0.004) and had fat pads and livers with higher yellow pigment deposition (P < 0.005). Litter moisture content altered microbiome composition but corn type did not. In conclusion, the main determinant of FPD in this study was exposure to wet litter. When compared with yellow and white corn, orange corn was associated with improved bird growth and reduced severity of footpad dermatitis, especially at later time points.


Asunto(s)
Citrus sinensis , Dermatitis , Enfermedades de las Aves de Corral , Alimentación Animal/análisis , Animales , Pollos , Dermatitis/veterinaria , Dieta/veterinaria , Femenino , Zea mays
8.
Poult Sci ; 99(9): 4398-4407, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32867983

RESUMEN

Consumer concern for broiler welfare has increased interest in chicken from slower growing (SG) broiler strains. Broilers from SG strains take longer to reach market weight, which may necessitate differences in management practices, such as stocking density. This study evaluated the effects of 2 stocking densities on production performance, body conformation, and welfare of broilers from 2 strains. Broilers from strains that reach market weight at age 42 D (CONV; N = 284) and at 63 D (SG; N = 284) were exclusively stocked into pens at a density of either 29 kg/m2 or 37 kg/m2. Birds were provided the same starter, grower, and finisher diets with diet phase changes occurring when SG bird body weight (BW) matched CONV. Live BW, body length, pelvic width, shank length, shank width, keel length, breast width, and breast depth were collected at 4 phases: Phase 1-chick placement, Phase 2-starter, Phase 3-grower, and Phase 4-finisher. At Phase 4, footpad dermatitis (FPD), hock burn (HB), and toe damage (TD) were scored. Feed conversion ratio (FCR) and mortality for each pen were recorded throughout the study. Final BW was similar (2.68 kg) for both strains and stocking densities of birds (P > 0.05). CONV bird FCR was 35% more efficient than SG (P < 0.0001). CONV birds had shorter bodies and shanks compared with SG birds at Phases 3 and 4 (P < 0.05). Slower growing birds stocked at 37 kg/m2 had the longest bodies and keel bones at Phase 4 (P < 0.01). Also at Phase 4, SG birds stocked at 29 kg/m2 had the lowest prevalence of HB (4%), yet the highest prevalence of TD (28%; P < 0.01). These results indicate differences in the effects of strain and stocking density on male broiler conformation, performance, and welfare and highlight the importance of tailoring management practices to the strain of broiler raised.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Pollos , Crianza de Animales Domésticos/métodos , Animales , Peso Corporal , Huesos/anatomía & histología , Pollos/anatomía & histología , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Masculino , Densidad de Población
9.
Poult Sci ; 98(9): 3578-3586, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30938804

RESUMEN

Many laying hen companies in the United States are pledging to move away from intensive conventional cages to extensive housing systems. Enriched colony cages (ECC) are a practical alternative to conventional cage systems. Scientific research is limited on the effects of ECC on hen production and welfare. Therefore, the objective of this study was to evaluate the effects of stocking density on welfare and performance with the overall outcome to provide guidance on stocking density for ECC. At 16 wk, W-36 pullets were placed into 2 commercial ECC housing systems. Within each ECC enclosure, hens were allocated into 1 of 6 stocking densities: A) 465 to 484 cm2/bird, B) 581 to 606 cm2/bird, C) 652 to 677 cm2/bird, D) 754 to 780 cm2/bird, E) 799 to 832 cm2/bird, and F) 923 to 955 cm2/bird. Body weight, egg production, mortality, and Welfare Quality data were collected each 28 d period from 17 to 68 wk. The 6 ECC stocking densities had several transient effects on production measures within age periods with no difference in hen-day production (P > 0.05). Body weight was affected by stocking density (P < 0.05) where hens raised at stocking density A (465 to 484 cm2/bird) weighed at least 25 g less than hens from other stocking densities. Stocking density differences for Welfare Quality assessments were only apparent for feather coverage. Hens raised at stocking density A (465 to 484 cm2) consistently had the poorest (P < 0.05) crop, keel, belly, back, and rump feather coverage. The keel, neck, and back body regions had poorer feather coverage when hens were raised at stocking densities B (581 to 606 cm2) and C (652 to 677 cm2) compared to hens from lower stocking densities (P < 0.05). Therefore, the minimum area per hen housed in commercial ECC systems should be 754 cm2 per bird for greater feather coverage.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bienestar del Animal , Pollos/fisiología , Vivienda para Animales , Animales , Femenino , Densidad de Población , Reproducción
10.
J Clin Psychiatry ; 43(7): 292-3, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7085590

RESUMEN

This paper reviews three cases of self-performed bilateral orchiectomy seen within a 2-year period at San Francisco General Hospital. All three cases were male to female transsexuals. The patients were not considered psychotic by the psychiatric consultant, although two patients admitted to past suicide attempts and psychiatric treatment. The patients' histories and treatment are reviewed and suggestions for diagnosis, management, and treatment planning are offered.


Asunto(s)
Castración , Automutilación/etiología , Transexualidad/complicaciones , Adulto , Castración/psicología , Carácter , Humanos , Masculino , Trastornos de la Personalidad/psicología , Psicoterapia , Automutilación/psicología , Intento de Suicidio/psicología , Transexualidad/psicología , Transexualidad/terapia
11.
Gen Hosp Psychiatry ; 2(1): 52-5, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7380250

RESUMEN

Use of physiological data displayed on Intensive Care Unit (ICU) monitors can be a valuable adjunct for the consulting psychiatrist interviewing a resistant post ingestion patient. Directing the patient's awareness to his own physiological responses at moments of repressed affect can aid in penetrating dense denial of depression and lead to better empathic contact between interviewer and patient. The equipment is unintrusive because it is part of the ICU environment, attached as standard procedure for management of such patients.


Asunto(s)
Intervención en la Crisis (Psiquiatría) , Monitoreo Fisiológico , Intento de Suicidio/psicología , Suicidio/psicología , Adulto , Consumo de Bebidas Alcohólicas , Actitud del Personal de Salud , Mecanismos de Defensa , Diazepam/envenenamiento , Humanos , Unidades de Cuidados Intensivos , Masculino , Pulso Arterial
12.
Gen Hosp Psychiatry ; 5(1): 55-61, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6840544

RESUMEN

Despite the position of the family as the basic social unit, the majority of studies of medical care utilization focus on individuals. In this preliminary study, nine families of high utilizers and 12 families of low utilizers were compared using the Moos Family Environment Scale and a semistructured interview. Significant differences were seen in structure, interactional patterns, and health-related behavior. The high utilizer families, as a whole, saw themselves as less expressive and more achievement-oriented. High utilizer children saw much more parental control than did low utilizer children. There was greater divergence in perspective between husbands and wives of high utilizing families than between spouses in low utilizing families. High utilizer families were less social than low utilizer families. There was greater use of tranquilizers and greater dissatisfaction with doctors in the high utilizer families as well.


Asunto(s)
Composición Familiar , Mal Uso de los Servicios de Salud , Servicios de Salud , Pacientes Ambulatorios/psicología , Pacientes/psicología , Logro , Adolescente , Actitud Frente a la Salud , Conflicto Psicológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoimagen , Medio Social , Socialización
13.
J Clin Rheumatol ; 1(4): 236-8, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19077985

RESUMEN

We describe a 10(1/2)-year-old black female who had severe angioedema, possibly triggered by penicillin, with respiratory distress as the initial presentation of systemic lupus erythematosus. In this patient, the Cl esterase inhibitor quantitative and functional serum levels were normal. Although there are several case reports with similar presentations in adults, this is the first case report in the pediatric age group.

14.
Med Tr Prom Ekol ; (7): 38-42, 2004.
Artículo en Ruso | MEDLINE | ID: mdl-15384396

RESUMEN

The authors obtained data demonstrating that peculiarities of each building object, wide variety of building operations at various stages of construction and constantly renewed technologies and construction materials complicate unequivocal evaluation of work conditions in building industry and require a system of occupational monitoring for health state among all construction industry occupations, in accordance with work conditions and length of service.


Asunto(s)
Arquitectura y Construcción de Instituciones de Salud , Exposición Profesional/efectos adversos , Lugar de Trabajo , Adulto , Estonia , Humanos , Persona de Mediana Edad , Factores de Tiempo
17.
Bull Menninger Clin ; 42(1): 25-34, 1978 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-630157
20.
Science ; 326(5959): 1525-9, 2009 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-20007897

RESUMEN

Organic aerosol (OA) particles affect climate forcing and human health, but their sources and evolution remain poorly characterized. We present a unifying model framework describing the atmospheric evolution of OA that is constrained by high-time-resolution measurements of its composition, volatility, and oxidation state. OA and OA precursor gases evolve by becoming increasingly oxidized, less volatile, and more hygroscopic, leading to the formation of oxygenated organic aerosol (OOA), with concentrations comparable to those of sulfate aerosol throughout the Northern Hemisphere. Our model framework captures the dynamic aging behavior observed in both the atmosphere and laboratory: It can serve as a basis for improving parameterizations in regional and global models.

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