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1.
Phys Rev Lett ; 128(13): 136801, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426705

RESUMO

The diffusion of photogenerated holes is studied in a high-mobility mesoscopic GaAs channel where electrons exhibit hydrodynamic properties. It is shown that the injection of holes into such an electron system leads to the formation of a hydrodynamic three-component mixture consisting of electrons and photogenerated heavy and light holes. The obtained results are analyzed within the framework of ambipolar diffusion, which reveals characteristics of a viscous flow. Both hole types exhibit similar hydrodynamic characteristics. In such a way the diffusion lengths, ambipolar diffusion coefficient, and the effective viscosity of the electron-hole system are determined.

2.
Photoacoustics ; 30: 100472, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36950519

RESUMO

Ultrahigh-frequency acoustic-phonon resonators usually require atomically flat interfaces to avoid phonon scattering and dephasing, leading to expensive fabrication processes, such as molecular beam epitaxy. Mesoporous thin films are based on inexpensive wet chemical fabrication techniques that lead to relatively flat interfaces regardless the presence of nanopores. Here, we report mesoporous titanium dioxide-based acoustic resonators with resonances up to 90 GHz, and quality factors from 3 to 7. Numerical simulations show a good agreement with the picosecond ultrasonics experiments. We also numerically study the effect of changes in the speed of sound on the performance of the resonator. This change could be induced by liquid infiltration into the mesopores. Our findings constitute the first step towards the engineering of building blocks based on mesoporous thin films for reconfigurable optoacoustic sensors.

3.
Res Vet Sci ; 136: 127-137, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33609970

RESUMO

Reproductive cycling in fattening gilts can be associated with undesirable effects, such as estrus-related aggressive behavior, reduced feed intake and, in production systems where gilts are co-housed with entire males, unwanted pregnancy. Immunization against Gonadotrophin Releasing Factor (IM) can temporarily suppress ovarian activity, including related negative consequences on animal welfare and productivity. Feed intake has been shown to be higher after IM, resulting in both increased growth and increased carcass fat. A series of studies was conducted to confirm these effects on production and look at their dynamics over time. Three trials were performed to a similar design, each involving 240 gilts divided into 4 experimental groups at 12 weeks of age. One group remained untreated while the others had the two dose, IM course completed 8, 6 or 4 weeks before harvest, which was on a single day at 24, 25 or 26 weeks of age depending on the study. Feed intake was measured daily and bodyweight weekly, allowing growth parameters to be calculated on a weekly basis and for specific longer periods. Carcass weight, backfat depth and lean meat percentage were recorded at harvest. No effects were observed before the second application of the immunological product (V2) and completion of the IM course. Starting in the second week after V2 all IM groups showed a marked and consistent increase in Average Daily Feed Intake (ADFI), typically peaking at over 120% of the control group 3 to 4 weeks after V2 and then slowly declining, but still remaining elevated at 8 weeks. Weekly Average Daily Gain (ADG) showed a similar pattern but with a faster decline, resulting in the initially favorable impact on feed efficiency becoming less favorable as the V2 to harvest interval (V2H) progressed. Carcass weights were higher in IM gilts and backfat depths were greater, with the effects increasing with increasing V2H. Correspondingly, carcass lean meat percentage tended to decrease, although the higher carcass weights meant that the absolute weight of lean meat remained similar or higher. Carcass yield was generally unaffected by IM, but some between-group differences were statistically significant, and it is possible that different factors predominated at different times after V2, creating a complex relationship with V2H duration. The optimum IM protocol will depend on local conditions and production objectives but, as a generalization and assuming ad libitum feeding, a shorter V2H will favor efficient growth, while a longer duration will maximize carcass changes, such as increased fat coverage. It is suggested that the growth performance changes seen after IM in gilts might be viewed as a process of adjustment to a heavier and fatter target body type.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Imunização/veterinária , Carne/análise , Sus scrofa/fisiologia , Animais , Feminino , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/imunologia , Fatores de Tempo
4.
J Pediatr Surg ; 30(6): 781-5, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7666306

RESUMO

To evaluate the effect of fundoplication on the gastric emptying (GE) of liquids, the authors studied 96 male Wistar rats divided into three main groups: group E (early postoperative), formed by 32 rats that received physiological saline as a test meal and whose gastric emptying was evaluated 8 days after surgery; group L (late postoperative), which received the same test meal but was evaluated 29 days after surgery; and group G (glucose), which received 5% glucose in water and was studied 8 days after surgery. Each group was subdivided in two subgroups of 16 animals: in one (atropine), the animals received intravenous (I.V.) atropine sulfate (0.3 mg/100 mg rat weight) 60 minutes before GE test; the other subgroup (controls) received I.V. physiological saline. In both subgroups 8 animals had been submitted to fundoplication and 8 to sham operation. Every test meal, containing 6 mg% red phenol, was infused by gravity through a metallic catheter. Gastric retention was determined by measuring the concentration of the marker in the liquid recovered from the stomach 10 minutes after infusion. In the animals of group E, fundoplication increased the gastric emptying of physiological saline, both in the control and the atropine subgroups. In the L group, gastric retention values were similar in fundoplication and sham-operated rats, suggesting an adaptation of the stomach to the fundoplication. In the G group, fundoplication enhanced GE among the control animals, but not among those receiving I.V. atropine sulfate. These results support the importance of gastric emptying studies in every patient to be submitted to fundoplication.


Assuntos
Fundoplicatura , Esvaziamento Gástrico , Adaptação Fisiológica , Animais , Atropina , Masculino , Período Pós-Operatório , Ratos , Ratos Wistar , Cloreto de Sódio , Estômago/fisiologia
5.
Arq Gastroenterol ; 18(4): 183-7, 1981.
Artigo em Português | MEDLINE | ID: mdl-7347599

RESUMO

The histopathologic aspects of the intrahepatic dysplasic bile ducts (cholangiodysplasia) found in two brothers, one of them asymptomatic, are discussed. This entity is characterized by interlobular bile ducts proliferation and portal fibrosis, without cholestasis but with chronic active cholangitis. The differential diagnosis and the probable genesis of the cholangiodysplasias are discussed.


Assuntos
Doenças dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos/anormalidades , Ductos Biliares Intra-Hepáticos/patologia , Pré-Escolar , Humanos , Lactente , Fígado/patologia , Masculino
6.
Rev Lat Am Enfermagem ; 5(Suppl): 51-7, 1997 May.
Artigo em Português | MEDLINE | ID: mdl-9481362

RESUMO

Through an epidemiological examination, the authors searched for co-morbidities and for psychiatric diagnoses related to alcohol. So, patients attended in a Psychiatric ward at an Emergency Service from 1988 to 1991 were investigated. The aim was to identify clinical diseases and another incidents that assault this population. The diagnoses examined were the ones related to alcohol, according to CID-9 (291; 303; 305.0) and the ones associated that do not belong to psychiatry 1835 cases were observed with diagnoses related to alcohol and among them 487 (26.5%) were concerning to the groups 291-303-305.0, which were associated to another psychiatric diagnoses. The larger frequency occurred in the groups 340-349 (Another central nervous system disorders) and 800-859 (Lesions and traumatic complications) with 80 (16.4%) patients, respectively. Through data observation by year, authors found that among the diagnoses related to alcohol (with clinical diagnoses associated), the 303 (Alcohol dependence syndrome) was the one that had the larger number of patients with 326 (67%) cases, followed by the 291 (Alcohol psychoses) with 117 (24%) cases and the 305.0 (Alcohol) with 44 cases (9%). In the period, the psychiatric diagnoses 303 and 291 appeared more frequently associated to the group of clinical diagnoses 340-349, with 55 (11.2%) and 12 (2.4%) cases respectively and the 305.0 had the group 800-859 with 10 (2%) cases as the more frequent.


Assuntos
Alcoolismo/complicações , Serviços de Emergência Psiquiátrica , Hospitalização/estatística & dados numéricos , Hospitais Gerais , Transtornos Mentais/complicações , Adolescente , Adulto , Idoso , Brasil , Criança , Comorbidade , Grupos Diagnósticos Relacionados , Feminino , Hospitalização/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Rev Lat Am Enfermagem ; 1(Suppl): 69-83, 1993 Dec.
Artigo em Português | MEDLINE | ID: mdl-7663735

RESUMO

The study's goal was to investigate the scientific production in Brazil's southeast region during 1987 to 1991 period. To do thal, letters were sent to 15 nursing schools that we had the address or through personal contact with someone from the institutions, asking a list of their scientific production during the period above stated. In order to be included in the study, the article had to meet some criteria that were established as important for a quantitative evaluation and classification. After that, qualitative classification was done by the article's tile using nine categories. The total of publications found were 2237 articles from which, 1585 were from nursing schools in the state of São Paulo, 222 from hospitals in the city of São Paulo, 296 from Federal University of Minas Gerais' School of Nursing and 134 from nursing schools in Rio de Janeiro.


Assuntos
Pesquisa em Enfermagem/estatística & dados numéricos , Brasil , Humanos , Pesquisa em Enfermagem/classificação , Pesquisa em Enfermagem/tendências , Editoração/classificação , Editoração/estatística & dados numéricos , Editoração/tendências , Escolas de Enfermagem , Inquéritos e Questionários
8.
Rev Esc Enferm USP ; 32(4): 314-24, 1998 Dec.
Artigo em Português | MEDLINE | ID: mdl-10614480

RESUMO

The present study have found out the number of patients assisted at the sector of Psychiatric Urgencies (SUP) and at the Midwifery Clinic of the University Hospital at Ribeirão Preto (HC), with the diagnosis 648.4 (Mental Disorders in Pregnancy, Childbirth and Puerperium), according to CID-9, from 1988 to 1993. Authors searched for reports containing informations on the care provided in these services. The sample was formed by women from 15 to 29 old years, whose disorders include psychotic disorders, depressive cases with or without attempts of suicide and non-specified mental disorders. Some of this disorders showed in comorbidity with others diagnostics. Resulting showed the need of nurses paying more attention to manifestations of these disorders and search for means to enable the identifications in the care provided at emergencies.


Assuntos
Serviços de Emergência Psiquiátrica/estatística & dados numéricos , Serviços de Saúde Materna/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Complicações na Gravidez/epidemiologia , Transtornos Puerperais/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Comorbidade , Feminino , Hospitais Universitários , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/enfermagem , Avaliação das Necessidades , Diagnóstico de Enfermagem , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/enfermagem , Transtornos Puerperais/diagnóstico , Transtornos Puerperais/enfermagem
9.
Rev Esc Enferm USP ; 30(1): 25-32, 1996 Apr.
Artigo em Português | MEDLINE | ID: mdl-8716338

RESUMO

The authors discuss positivism foundations; the most remarkable influences to comtian's philosophy structuration; how Comte's ideas, as doctrine in so far as method, dominate society's thoughts, passing beyond XIX century and reaching XX century; and how the positivist doctrine and empirical method influenced Nursing conceptions about science and about human being/environment/disease.


Assuntos
Pesquisa em Enfermagem/história , Filosofia em Enfermagem/história , Filosofia/história , Brasil , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , América do Norte
10.
Int J Gynecol Cancer ; 16(3): 1055-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16803485

RESUMO

The objective of this study was to assess whether human papillomavirus (HPV) detection with hybrid capture II (HC II) can help predict the presence and the nature, glandular or squamous, of histologic cervical lesions in women referred due to atypical glandular cells (AGC) or high-grade squamous intraepithelial lesion (HSIL). A total of 247 women were included. Referral Pap smears comprised AGC (51 cases), AGC plus HSIL (28 cases), adenocarcinoma in situ (10 cases), and HSIL (158 cases). All patients were tested for high-risk HPV with HC II and had a histologic assessment of their cervix. Histologic analysis showed 38 women with (15.3%) cervicitis, 194 with (75.5%) squamous lesions, and 15 with (9.2%) glandular neoplasia. The overall rate of high-risk HPV detection was 77%. Almost 70% of AGC-HPV-negative patients did not have a pathologically proven cervical neoplasia, whereas 76% of women with AGC-HPV-positive result were diagnosed with a squamous or glandular neoplasia. Most (95%) of the lesions in patients with AGC-HSIL were of squamous nature, and HPV detection did not contribute to their differentiation from glandular lesions. We conclude that in women with AGC, HPV positivity strongly correlated with the presence of glandular or squamous cervical lesion but did not help distinguishing women with squamous from those with glandular neoplasia.


Assuntos
Carcinoma de Células Escamosas/virologia , Programas de Rastreamento/métodos , Papillomaviridae/isolamento & purificação , Doenças do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/virologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Sondas de DNA de HPV , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/epidemiologia , Neoplasias Epiteliais e Glandulares/virologia , Neoplasias de Células Escamosas/epidemiologia , Neoplasias de Células Escamosas/virologia , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/virologia , Valor Preditivo dos Testes , Doenças do Colo do Útero/diagnóstico , Doenças do Colo do Útero/epidemiologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia
11.
Pediatr Radiol ; 20(3): 163-5; discussion 169, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2191265

RESUMO

Fourteen children with adrenal cortical carcinoma were evaluated by ultrasonography. The neoplasms, 2.5 cm-19 cm in maximum diameter, were all well circumscribed. The four smaller lesions were either homogeneously hypoechoic (2 patients) or generally hyperechoic (2 patients). In the 10 patients with larger tumors, a complex predominantly echogenic pattern was demonstrated, eight of which contained radiating linear echoes, the "scar sign". This finding, although not specific, when present in a large adrenal mass, is suggestive of a cortical carcinoma. Associated findings of vascular invasion or retroperitoneal adenopathy supported the diagnosis of a malignant adrenal neoplasm in 3 patients.


Assuntos
Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Ultrassonografia
12.
Pediatr Radiol ; 20(8): 571-4, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2250998

RESUMO

Four children with benign intraperitoneal lipomatous tumors (mesenteric lipoma, mesenteric lipoblastoma, omental lipoblastoma and mesenteric mesenchymoma) are reported. The ultrasonographic findings of these unusual pediatric masses are described and correlated with their conventional radiologic and pathologic appearance. The pre-operative diagnosis of these entities can be suggested by these features.


Assuntos
Lipoma/diagnóstico por imagem , Neoplasias Peritoneais/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lipoma/patologia , Masculino , Mesenquimoma/diagnóstico por imagem , Mesenquimoma/patologia , Mesentério , Omento , Neoplasias Peritoneais/patologia , Radiografia , Ultrassonografia
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