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1.
Rev Sci Instrum ; 93(9): 093508, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182487

RESUMO

This paper describes two new helical arrays of magnetic coils recently installed inside the TJ-II vacuum vessel. Their main objective is the precise measurement of the spatial periodicity of the magnetohydrodynamic perturbations usually found in the TJ-II plasmas. Given the high probability of coil failures due to the harsh plasma environment and in view of the extremely difficult access to the TJ-II vessel interior for maintenance, the coil system has been divided in two quasi-identical helical arrays. Both arrays consist of 32 triaxial sensors measuring orthogonal components of the local magnetic field along an ideal helical path whose trajectory runs close to the plasma edge. A description of the main characteristics of coils and arrays as well as their nominal positioning along an ideal helical path, inside the vessel, is given. A precise experimental determination of the real spatial orientation of the coils is performed by comparing the signals measured in current ramp-up and ramp-down experiments with calculations based on a filamentary model for the TJ-II magnetic coils. After this fine calibration procedure, it is possible to analyze the dependence of the amplitude of the measured magnetic field and its fluctuations as a function of the coil distance to the last closed flux surface. The study of the phase evolution of the parallel and perpendicular oscillatory components is also enabled. Finally, two examples of mode number determination are shown. One corresponds to a low frequency mode appearing in pure electron cyclotron resonance heating plasma, and the other one shows several modes observed during combined injection of both co and counter neutral beams and identified as shear Alfvén waves.

2.
Eat Weight Disord ; 26(2): 703-707, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32146595

RESUMO

PURPOSE: This cross-sectional study aimed at comparing the quality of life (Qol), the prevalence of psychiatric diagnosis and pharmacological treatment in 104 candidates to bariatric surgery according to the degree of obesity (class 2 vs. class ≥ 3 obesity). METHODS: All surgical candidates underwent a detailed psychiatric interview based on DSM-5 criteria, including sociodemographic, clinical, psychological and psychiatric data. Participants completed the Binge Eating Scale (BES) and the 12-Item Short Form Health Survey (SF-12). RESULTS: Overall, bariatric candidates reported a significant impairment in the physical (PCS 38.8 [95% CI 36.2-41.5]) and mental (MCS 42.2 [95% CI 40.4-43.9]) components of Qol compared to population norms (p < 0.001 for both). Subjects with class 2 obesity scored significantly lower in the MCS compared to those with class 3 (38.7 (8.1) vs. 43.6 (8.4), p = 0.008). No other statistically significant differences were found between the two groups in terms of sociodemographic and clinical variables. CONCLUSION: These data support the usefulness of Qol assessment in bariatric candidates as a sensible screening parameter, especially in patients with lower BMI, in whom MCS could identify the need for early psychosocial intervention. LEVEL OF EVIDENCE: Level III, case-control analytic study.


Assuntos
Cirurgia Bariátrica , Transtornos Mentais , Obesidade Mórbida , Índice de Massa Corporal , Estudos Transversais , Humanos , Qualidade de Vida
3.
Reprod Domest Anim ; 52(4): 632-639, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28378464

RESUMO

The aim of this research has been to evaluate the presence of anomalies in the ovarian cycle activity during postpartum and to verify whether 72-hr dietary fasting during the dominance phase, the phase before ovulation, might modify the ovarian follicle population. The presence of anomalies in ovarian cycle activity has been evaluated in 30 Italian Friesian cows starting from 20 days postpartum until 211 days of lactation. Long oestrus and brief dioestrus or scarce luteal activity have been the main anomalies found through measuring progesterone concentrations in the whey. Until 100 days of lactation, the BCS values of the problematic animals have been significantly lower than those in animals with normal ovarian activity. After 100 days of lactation, the ovarian anomalies continued to appear despite the fact that all the animals have reached comparable BCS values. Starting from the results of this trial, the effect of 72-hr dietary fasting on dominant follicles has been studied in six cows. Ultrasonography revealed that the diameter of the follicles at 71 days postpartum has been significantly lower than at 181 days. A 72-hr dietary restriction at 101 and 211 days postpartum did not affect the size of the dominant follicle. However, at 101 days postpartum, half of the animals presented follicular cysts. The effect of fasting differed if the animal has been in early postpartum or 211 days of lactation. Further researches are necessary to understand how different metabolic conditions can modify the follicular population but on the other hand the study shows the utility for farmers and field veterinarians of monitoring the resumption of the ovarian cycle postpartum through the whey progesterone concentrations.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Folículo Ovariano/fisiologia , Animais , Composição Corporal , Dieta/veterinária , Feminino , Lactação/fisiologia , Leite/química , Ovulação , Período Pós-Parto , Progesterona/análise
4.
Rev Sci Instrum ; 87(11): 11D304, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910389

RESUMO

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.

5.
J Dairy Sci ; 96(5): 3023-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23522680

RESUMO

The aim of this study was to evaluate the hypothalamic-pituitary-adrenal (HPA) axis activity of Holstein-Friesian and crossbreed F1 heifers by analysis of the cortisol concentrations in hair samples. Cortisol, the primary hormone of the HPA axis, is the biological endpoint for the investigation of the HPA response. The study was conducted on 290 prepubertal heifers; 142 heifers were pure Holstein-Friesian and 148 were crossbreed F1 heifers obtained from the 3-way rotational system with Swedish Red and Montbéliarde breeds. Extraction was performed on the hair using methanol, and cortisol concentrations were determined by a radioimmunoassay method. Cortisol concentrations measured in regrown hair of crossbreed F1 heifers were significantly lower than those in hair of Holstein-Friesian heifers. This result helps us to better understand the differences in HPA activity and allostatic load between Holstein-Friesian and crossbreed F1 heifers and allows us to better assess the adaptability of these animals to the environment and the importance of crossbreed traits for profitability in dairy farming.


Assuntos
Cabelo/química , Hidrocortisona/sangue , Animais , Cruzamento , Bovinos/fisiologia , Feminino , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Radioimunoensaio/veterinária
6.
Rev Sci Instrum ; 80(7): 073502, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19655948

RESUMO

A Doppler reflectometer system has recently been installed in the stellarator TJ-II. The system is optimized for the Q-band (33-50 GHz) and the high-curvature plasmas produced in TJ-II. The launch angle of the microwave beam can be controlled by a steerable mirror to obtain angles between +/-20 degrees enabling the measurement of perpendicular wave numbers in the range of 3-15 cm(-1). The available angular range allows for comparisons between positive and negative values and additionally for calibration of the system. Localization and k(perpendicular)-estimation is done via the three-dimensional ray/beam-tracing code TRUBA. First measured spectra and radial profiles of the perpendicular velocity of plasma density fluctuations are presented.

7.
Dement Geriatr Cogn Disord ; 16(4): 296-300, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14512727

RESUMO

Object and action naming and comprehension were tested in frontotemporal dementia (frontal variant, FTD), in Alzheimer's disease (AD) and in controls. Although lower scores were obtained by all groups, we can confirm that actions were proportionally more impaired in FTD. The correlation between action naming deficit and severity of dementia was stronger in this group than in AD. The correlation analysis also suggested that the naming disorder was different in nature in FTD (mostly a dysexecutive deficit) and in AD (mostly a linguistic disorder). Our explanation is that since verbs are supposed to be more demanding of executive resources than nouns, a higher sensitivity to verbs should be expected in any brain pathology, but mostly in FTD in which executive resources are typically reduced.


Assuntos
Demência/psicologia , Comportamento Verbal , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Demência/fisiopatologia , Lobo Frontal , Humanos , Desempenho Psicomotor , Semântica
8.
J Dairy Sci ; 85(10): 2699-704, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12416825

RESUMO

Theoretical cheese yield can be estimated from the milk fat and casein or protein content of milk using classical formulae, such as the VanSlyke formula. These equations are reliable predictors of theoretical or actual yield based on accurately measured milk fat and casein content. Many cheese makers desire to base payment for milk to dairy farmers on the yield of cheese. In small factories, however, accurate measurement of fat and casein content of milk by either chemical methods or infrared milk analysis is too time consuming and expensive. Therefore, an empirical test to predict cheese yield was developed which uses simple equipment (i.e., clinical centrifuge, analytical balance, and forced air oven) to carry out a miniature cheese making, followed by a gravimetric measurement of dry weight yield. A linear regression of calculated theoretical versus dry weight yields for milks of known fat and casein content was calculated. A regression equation of y = 1.275x + 1.528, where y is theoretical yield and x is measured dry solids yield (r2 = 0.981), for Cheddar cheese was developed using milks with a range of theoretical yield from 7 to 11.8%. The standard deviation of the difference (SDD) between theoretical cheese yield and dry solids yield was 0.194 and the coefficient of variation (SDD/mean x 100) was 1.95% upon cross validation. For cheeses without a well-established theoretical cheese yield equation, the measured dry weight yields could be directly correlated to the observed yields in the factory; this would more accurately reflect the expected yield performance. Payments for milk based on these measurements would more accurately reflect quality and composition of the milk and the actual average recovery of fat and casein achieved under practical cheese making conditions.


Assuntos
Queijo , Indústria de Laticínios , Lipídeos/análise , Proteínas do Leite/análise , Leite/química , Animais , Caseínas/análise , Bovinos , Feminino , Modelos Lineares , Reprodutibilidade dos Testes
9.
Theriogenology ; 58(5): 899-910, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12212890

RESUMO

The effect of an acute energy deficit on the hormone balance of dominant follicles was studied in six normally-cycling, high-yielding Italian Friesian cows at 60 and 90 days after calving. At 60 days after calving, the cows, which had been fed according to their maintenance and production requirements, were synchronized and follicular fluid was collected from the dominant follicles under ultrasound guidance. At 90 days after calving, the same protocol was used on the same cows, which had been subjected to an acute dietary restriction since the day of the second prostaglandin treatment for synchronization. At the follicular level, the dietary restriction caused a significant reduction (P < 0.05) in the concentration of estradiol-17beta and a significant increase (P < 0.05) in NEFA. There were no significant differences in follicular diameter, follicular concentrations of progesterone, and Insulin-like Growth Factor-I (IGF-I). The amount of IGFBP2 and IGFBP3 in follicular fluid increased. The results suggest that an acute dietary restriction induces substantial changes at the dominant follicle level, despite the fact that the recruitment and selection phase occurred before the cows' diet was restricted.


Assuntos
Bovinos/metabolismo , Ingestão de Energia , Privação de Alimentos , Folículo Ovariano/metabolismo , Animais , Composição Corporal , Estradiol/análise , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/sangue , Feminino , Líquido Folicular/química , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Fator de Crescimento Insulin-Like I/análise , Folículo Ovariano/anatomia & histologia , Progesterona/análise
10.
J Neurol Neurosurg Psychiatry ; 70(1): 22-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11118243

RESUMO

OBJECTIVES: Patients with Alzheimer's disease (AD) showing a selective impairment of episodic and semantic memory have recently been classified as affected by focal temporal lobe dysfunction (FTLD) and considered as a distinct subgroup of patients affected by a particular form of AD. The aim was to compare the cerebral perfusion of patients with AD with FTLD and patients with AD with the more typical profile of diffuse cognitive impairment (dAD). METHODS: Ten patients with AD with FTLD, 14 patients with AD with dAD, and 12 normal controls were studied. All the 24 patients with AD underwent a complete neuropsychological assessment. SPECT examination with [(99m)Tc]-HMPAO, using a four head brain dedicated tomograph, was performed in patients and controls. Tracer uptake was quantified in 27 regions of interest (ROIs), including lateral and mesial temporal areas. Mean counts in the 27 ROIs of controls, patients with FTLD and those with dAD were compared using an ANOVA for repeated measures with Bonferroni's correction. A logistic regression analysis, followed by a receiver operating characteristic (ROC) analysis, was also applied to select SPECT patterns which significantly differentiated patients with FTLD and those with dAD. RESULTS: Two scintigraphic patterns of abnormalities, shaping a double dissociation between the FTLD and dAD groups, emerged: a bilateral mesial temporal hypoperfusion, characteristic of FTLD and a posterior parietal (and temporal parietal) hypoperfusion characteristic of patients with dAD. CONCLUSIONS: These scintigraphic findings provide further support to the hypothesis that FTLD is not a mere stage but a distinct anatomoclinical form of AD. The combination of neuropsychological tests and [(99m)Tc]-HMPAO SPECT may be very useful in identifying patients with FTLD from the wider group of patients with dAD. This issue is particularly worthwhile, as there is increasing evidence that patients with FTLD have a slower rate of cognitive decline.


Assuntos
Doença de Alzheimer/fisiopatologia , Circulação Cerebrovascular/fisiologia , Transtornos Cognitivos/fisiopatologia , Lobo Temporal/fisiopatologia , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Análise de Variância , Transtornos Cognitivos/diagnóstico por imagem , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Lobo Temporal/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único
13.
Ital J Neurol Sci ; 16(6): 387-9, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8626216

RESUMO

In a patient who developed clinical signs of intracranial hypertension, bilateral papilledema and diplopia, in association with mild hypotension, hyponatremia and hyperkalemia, the hypothesis of Addison's disease was raised and confirmed. Substitutional therapy led to complete recovery. The present paper represents the first report of pseudotumor cerebri as the only clinical sign of an Addisonian crisis.


Assuntos
Doença de Addison/complicações , Pseudotumor Cerebral/etiologia , Doença de Addison/diagnóstico , Doença de Addison/tratamento farmacológico , Adolescente , Feminino , Humanos , Hidrocortisona/uso terapêutico , Imageamento por Ressonância Magnética , Pseudotumor Cerebral/diagnóstico
14.
J Neurol ; 242(6): 359-66, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7561963

RESUMO

Twenty-three patients with Alzheimer's dementia (AD) in relatively early stages and 40 patients with other cognitive disorders of vascular or degenerative aetiology underwent neuropsychological examination and [99mTc]-HM PAO single photon emission computed tomography (SPECT). In contrast to the commonly accepted notion of a posterior temporoparietal reduction of tracer uptake as the typical SPECT pattern of AD, the most consistent feature found in the SPECT images of our AD patients was a hippocampal uptake deficit, associated with a variable degree of temporal, parietal and frontal deficit (extending from the posterior to the anterior regions), according to the severity of the disease. These results support the theory of AD as a "hippocampal dementia", at least in the early stages. Neuropsychological tests were found to be somewhat more specific and more accurate than SPECT in distinguishing AD from non-AD cases.


Assuntos
Doença de Alzheimer/diagnóstico , Compostos de Organotecnécio , Oximas , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Humanos , Testes Neuropsicológicos , Estudos Retrospectivos , Tecnécio Tc 99m Exametazima
15.
Int J Neurosci ; 78(1-2): 9-20, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7829295

RESUMO

It is still controversial whether verbal and pictorial stimuli are independently processed and stored in memory, as assumed by the dual code hypothesis, or a single code is used both for verbal and for pictorial stimuli, as assumed by the verbal loop hypothesis and by the propositional code hypothesis. According to the first hypothesis, verbal and pictorial memory are independently disrupted by brain damage, whereas according to the second hypothesis a co-occurrence of verbal and pictorial memory disorders are usually observed. To test these contrasting predictions, we constructed a verbal and a pictorial memory task very similar with respect to testing procedures and to material to be memorized and we administered them to 33 left and 27 right brain-damaged patients and to 21 normal controls. The following results were obtained: 1) Disorders of verbal and of pictorial memory were dissociated by brain injury in about one-third of our patients; 2) A consistent relationship was observed between laterality of lesion and type of selective memory impairment, since word recognition was selectively impaired by left and picture recognition by right brain injury; 3) However, only on the test of verbal memory was a significant difference between right and left brain-damaged patients obtained, whereas on the test of pictorial memory only a nonsignificant trend in the opposite direction was observed. These data are in favor of the dual code hypothesis and suggest that the links between left hemisphere and verbal code may be stronger than the relationship between right hemisphere and pictorial code.


Assuntos
Encefalopatias/fisiopatologia , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Lateralidade Funcional/fisiologia , Transtornos da Memória/fisiopatologia , Comportamento Verbal/fisiologia , Percepção Visual/fisiologia , Adulto , Idoso , Encefalopatias/complicações , Humanos , Transtornos da Memória/etiologia , Rememoração Mental/fisiologia , Pessoa de Meia-Idade
16.
Cancer Genet Cytogenet ; 76(2): 106-11, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7923057

RESUMO

The short area of chromosome 17 is a frequent target for deletions in human tumors, including breast cancer. We have investigated by restriction fragment polymorphism analysis the pattern of loss of heterozygosity (LOH) at four loci on 17p13.1-17pter in a panel of 110 primary human breast carcinomas. A copy of the p53 gene was lost in 23% of the informative cases. Point mutations in the p53 gene were statistically associated with LOH at the same locus (p = 0.003) but not at other loci on 17p13.3-17pter. A second region bordered by the loci D17S5/D17S28 (17p13.3) and D17S34 (17pter) is also affected by LOH, independent of point mutations in the p53 gene. We propose the presence of a second tumor suppressor gene within this region. In support of this hypothesis is the significant association (p = 0.005) between LOH at the D17S5/D17S28, but not at the TP53 or D17S34 loci, and tumors having a high S-phase index.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 17 , Genes Supressores de Tumor/genética , Fase S/genética , Alelos , Deleção Cromossômica , Genes p53 , Heterozigoto , Humanos , Mutação Puntual/genética , Reação em Cadeia da Polimerase
18.
Pathol Res Pract ; 190(1): 69-76, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8065991

RESUMO

Twelve pathologists independently examined and classified a set of 25 cases of non palpable breast lesions selected from the archival files of the Pathology Department in Florence. A final consensus diagnosis was reached for all cases at a slide seminar. Individual diagnoses were first combined in 3 broad categories (benign lesion, in situ and invasive carcinoma), then compared to each other and then to the "consensus". Results show that among these 12 pathologists there was complete agreement in 14 cases. Discrepancies for the other 11 cases varied in the number of pathologists and diagnostic categories involved. Overall agreement was excellent (median kappa 0.86) but cases of potentially harmful errors were evident. The authors discuss these findings in the frame of a breast cancer screening program planning.


Assuntos
Neoplasias da Mama/patologia , Doenças Mamárias/patologia , Erros de Diagnóstico , Feminino , Humanos , Reprodutibilidade dos Testes
20.
Clin Chim Acta ; 217(1): 63-73, 1993 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-8222284

RESUMO

We have undertaken a systematic study of primary human breast tumor DNAs to identify and characterize frequently occurring somatic mutations. Loss of heterozygosity (LOH) was found on chromosomes 1p (37%), 1q (20%), 3p (30%), 7 (41%), 13q (30%), 17p (49%), 17q (29%) and 18q (34%) in our tumor DNA panel. Specific subsets of tumors could be defined based on the particular collection of mutations they contained. One goal of these studies has been to determine whether there is a significant association between specific mutations and clinical parameters of the disease. We have found that LOH on chromosome 17p in tumor DNAs is associated with breast tumors having a high proliferative index and that LOH on chromosome 7 is associated with patients having a poor prognosis. Our analysis of chromosome 17 suggests that there may be as many as four tumor suppressor genes affected in primary human breast tumors.


Assuntos
Neoplasias da Mama/genética , Animais , Neoplasias da Mama/patologia , DNA de Neoplasias/genética , Variação Genética , Humanos , Camundongos , Camundongos Transgênicos , Mutação
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