Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
1.
J Dairy Sci ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38554821

RESUMO

The use of sensor-based measures of rumination time as a parameter for early disease detection has received significant attention in scientific research. This study aimed to assess the accuracy of health alerts triggered by a sensor-based accelerometer system within 2 different management strategies on a commercial dairy farm. Multiparous Holstein cows were enrolled during the dry-off period and randomly allocated to conventional (CON) or sensor-based (SEN) management groups at calving. All cows were monitored for disorders for a minimum of 10 DIM following standardized operating procedures (SOPs). The CON group (n = 199) followed an established monitoring protocol on the farm. The health alerts of this group were not available during the study but were later included in the analysis. The SEN group (n = 197) was only investigated when the sensor system triggered a health alert, and a more intensive monitoring approach according to the SOPs was implemented. To analyze the efficiency of the health alerts in detecting disorders, the sensitivity (SE) and specificity (SP) of health alerts were determined for the CON group. In addition, all cows were divided into 3 subgroups based on the status of the health alerts and their health status, to retrospectively compare the course of rumination time. Most health alerts (87%, n = 217) occurred on DIM 1. For the confirmation of diagnoses, health alerts showed SE and SP levels of 71% and 47% for CON cows. In SEN cows, a SE of 71% and 75% and SP of 48% and 43% were found for the detection of ketosis and hypocalcemia, respectively. The rumination time of the subgroups was affected by DIM and the interaction between DIM and the status of health alert and health condition.

2.
Phys Rev Lett ; 129(9): 093402, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36083677

RESUMO

We investigate ultracold collisions in a novel mixture of ^{6}Li and ^{53}Cr fermionic atoms, discovering more than 50 interspecies Feshbach resonances via loss spectroscopy. Building a full coupled-channel model, we unambiguously characterize the ^{6}Li-^{53}Cr scattering properties and yield predictions for other isotopic pairs. In particular, we identify various Feshbach resonances that enable the controlled tuning of elastic s- and p-wave ^{6}Li-^{53}Cr interactions. Our studies thus make lithium-chromium mixtures emerge as optimally suited platforms for the experimental search of elusive few- and many-body regimes of highly correlated fermionic matter, and for the realization of a new class of ultracold polar molecules possessing both electric and magnetic dipole moments.

3.
Rev Sci Tech ; 41(1): 100-106, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35925632

RESUMO

Insects play a crucial role in research. Many laboratories are developing technologies to control insect vectors or agricultural pests by using genetic modifications that either reduce insect reproduction or increase refractoriness to disease transmission. Those tools include gene-drive elements that may spread such genetic traits in a selfsustaining and cost-effective manner. Since international research collaborations are nowadays routine, movement of genetically modified insects between laboratories under different regulatory jurisdictions is very common. This article describes the requirements and guidelines for transportation of genetically modified insects for research. The author draws upon the experience gained by an Italian laboratory, in its role as a research centre involved in shipments of wild and modified mosquitoes, within an international research consortium developing sustainable tools for malaria control.


Les insectes jouent un rôle essentiel dans la recherche. Nombre de laboratoires mettent actuellement au point des technologies qui visent à lutter contre les insectes vecteurs de maladies ou ravageurs des cultures, en introduisant des modifications génétiques dont le but est de limiter la reproduction des insectes ou de les rendre résistants à la transmission des maladies. Ces outils font appel au guidage génétique, qui permet la transmission héréditaire de ces traits de manière durable et peu onéreuse. Dans le contexte actuel où les collaborations scientifiques au niveau international sont devenues systématiques, les transferts d'insectes génétiquement modifiés entre laboratoires de différents pays sont désormais très fréquents. L'auteur décrit les dispositions réglementaires et les directives applicables au transport d'insectes génétiquement modifiés à des fins de recherche. Il s'appuie sur l'expérience acquise par un laboratoire italien doté du statut de centre de recherche et qui, à ce titre, participe aux expéditions de moustiques sauvages et génétiquement modifiés dans le cadre d'un consortium scientifique international pour la mise au point d'outils durables de lutte contre le paludisme.


Los insectos son un elemento fundamental para la investigación. Numerosos laboratorios están desarrollando técnicas destinadas a combatir a insectos que actúan como vectores o constituyen plagas agrícolas empleando modificaciones genéticas que bien frenan la reproducción del insecto o bien confieren mayor resistencia a la transmisión de enfermedades. Entre tales herramientas figuran elementos de genética dirigida que posibilitan la propagación de esos rasgos genéticos de manera a la vez autosostenida y rentable. Teniendo en cuenta lo habituales que son hoy en día las iniciativas de investigación que entrañan colaboración internacional, el traslado de insectos genéticamente modificados entre laboratorios sujetos a diferentes jurisdicciones reglamentarias es también algo muy común. El autor expone los requisitos y directrices que rigen el transporte de insectos genéticamente modificados con fines de investigación, basándose en la experiencia de un laboratorio italiano que, como parte de un consorcio internacional de investigación que elabora herramientas sostenibles de lucha antipalúdica, cumple funciones de centro de investigación en cuanto al transporte de mosquitos salvajes o modificados.


Assuntos
Culicidae , Malária , Animais , Animais Geneticamente Modificados , Culicidae/genética , Insetos/genética , Laboratórios , Malária/prevenção & controle , Malária/veterinária , Mosquitos Vetores
4.
Eur Rev Med Pharmacol Sci ; 26(2): 558-572, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35113432

RESUMO

OBJECTIVE: The aim of this study was to assess the impact of glucose control, diabetes-related complications and cardiometabolic risk factors on the risk of diabetic foot ulcers (DFUs) and DFU complications in Albanian adult inpatients with T2D. PATIENTS AND METHODS: We conducted a retrospective case-control study on 482 Albanian adult inpatients with T2D. DFU was defined as a full-thickness skin lesion requiring ≥14 days for healing and was classified at the time of hospital admission. Demographic and biochemical parameters of the study participants, the presence of comorbidities and diabetes-related complications at the time of hospital admission were evaluated through a retrospective chart review. RESULTS: Mean age of study participants was 54.8±10.7 years. Participants (284 males and 198 females) were divided into two groups: DFU (cases; n=104) and non-DFU (controls; n=378). Multivariate analysis (performed by a logistic regression model) revealed that the most relevant independent variables associated with DFU were BMI [OR=0.62; p=0.007], HDL-cholesterol [OR=0.00; p<0.0001], triglycerides [OR=7.48; p=0.0004], cigarette smoking [OR=26.46; p=0.005], duration of diabetes [OR=1.53; p<0.0001], fasting plasma glucose (FPG) [OR=1.06; p<0.0001], systolic blood pressure (SBP) [OR=1.13; p=0.0004] and insulin therapy alone [OR=0.11; p=0.02]. ROC curve analysis showed that FPG (AUC=0.83), glycated hemoglobin (HbA1c) (AUC=0.75), triglycerides (AUC=0.78) and HDL-cholesterol (AUC=0.82) were the most reliable biomarkers able to detect DFU. In the DFU group, the most relevant independent variables associated with previous minor lower-extremity amputations (LEAs) were represented by HbA1c [OR=1.47; p=0.03], age <55 years [OR=0.12; p=0.05] and female sex [OR=4.18; p=0.03]; whereas the most relevant independent variables associated with diabetic peripheral neuropathy (DPN) were HbA1c [OR=1.70; p=0.006], SBP [OR=1.08; p=0.05], BMI [OR=1.20; p=0.03] and lack of cigarette smoking [OR=0.07; p=0.01]. Correlation analysis (performed through the nonparametric Spearman's rank correlation test or through the parametric Pearson test, as appropriate) revealed a significant positive relationship between HbA1c and FPG (r=0.58; p<0.0001), ulcer surface area (r=0.50; p<0.0001), ulcer grade (r=0.23; p=0.02), minor LEAs (r=0.20; p=0.04), DPN (r=0.41; p<0.0001), and metformin therapy alone (r=0.72; p<0.0001). There was a significant inverse correlation between HbA1c and insulin therapy alone (r=-0.31; p=0.01) and combined metformin and insulin therapy (r=-0.60; p<0.0001). Both DFU and non-DFU groups exhibited suboptimal mean LDL-cholesterol levels (>100 mg/dl) and mean HbA1c values >7.5%. Moreover, in DFU group HbA1c values were markedly elevated (≥10%) particularly in patients with a grade 3 ulcer and an ulcer surface area ≥4 cm2, as well as in patients with history of minor LEAs and in patients affected by DPN. CONCLUSIONS: The present study suggested that longer duration of diabetes, cigarette smoking, lower HDL-cholesterol levels, poor glucose control, and elevated triglyceride and SBP values may all represent major risk factors for the development of DFU in Albanian patients with T2D. Thus, community interventions and health policies aimed to improve the management of diabetes and related cardiometabolic risk factors should be urgently implemented in Albania, in order to prevent DFUs and other diabetes complications in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Pé Diabético/diagnóstico , Pé Diabético/epidemiologia , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
5.
Neuropsychol Rehabil ; 31(3): 414-431, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31855105

RESUMO

Understanding of emotional adjustment after stroke is limited. Under one-third of stroke survivors reporting emotional problems receive support. The aim of this study was to explore the process of emotional adjustment post-stroke and investigate the role played by participation in an online stroke community. We applied thematic analysis to 124 relevant posts within 114 discussion threads, written by 39 survivors and 29 carers. The contribution of online community engagement to emotional adjustment was explored using the Social Support Behaviour Code. Stroke survivors share common experiences of emotional adjustment and may not necessarily reach complete acceptance. Positive and negative trajectories of emotional adjustment were identified. Survivors progressed along, or moved between, positive and negative pathways not in a time-dependent manner but in response to "trigger events," such as physical setbacks or anti-depressant treatment, which may occur at any chronological time. An adapted version of Suhr's 1990 Social Support Behaviour Code showed that support provided through the online community took many forms, including advice, teaching, empathy and normalization of concerns. Participation in the stroke community was itself deemed to be a positive "trigger event." There is need to improve awareness of emotional adjustment and their "triggers" amongst stroke survivors, carers and clinicians.


Assuntos
Ajustamento Emocional , Acidente Vascular Cerebral , Cuidadores , Humanos , Pesquisa Qualitativa , Acidente Vascular Cerebral/complicações , Sobreviventes
6.
Endocr Res ; 40(3): 127-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774471

RESUMO

OBJECTIVES: Insulin resistance and central obesity have been implicated in the pathogenesis of hypoadiponectinemia in obesity. The aim of this study is to evaluate circulating post-prandial adiponectin in relation to glucose and insulin metabolism, indexes of insulin resistance and sensitivity and, indexes of body fat accumulation and distribution in obese men. METHODS: Twenty-eight non-diabetic men underwent an OGTT followed by an oral fat load and were studied at baseline and for 5 h post-prandially for serum adiponectin, glucose and insulin. Insulin resistance was estimated by Homeostasis model assessment (HOMA) and insulin sensitivity by Matsuda index. Body fat accumulation and distribution were evaluated by anthropometric indexes and multiple slices MRI of the abdomen and hip. RESULTS: Adiponectin was negatively correlated to insulin levels. Fasting and area under the curve (AUC) adiponectin levels were negatively correlated to HOMA (both p < 0.01) and positively to Matsuda index (both p < 0.05). Negative correlations between fasting adiponectin and total fat (r = -0.408, p < 0.05), AUC adiponectin and subcutaneous, visceral and total fat (r = -0.375, -0.413 and -0.475 respectively, all p < 0.05) at L3-L4 were found, and negative correlations between fasting adiponectin and subcutaneous (r = -0.402, p < 0.05) and total fat (r = -0.491, p < 0.05) and between AUC adiponectin and subcutaneous and total fat (r = -0.506 and -0.547, respectively, both p < 0.01) were present at L4-L5. CONCLUSIONS: Circulating adiponectin is inversely correlated to both visceral and subcutaneous fat in non-diabetic men, implying that both compartments are important for adiponectin levels. The best correlation is found at measurement site L4-L5.


Assuntos
Adiponectina/sangue , Adiposidade/fisiologia , Jejum/sangue , Gordura Intra-Abdominal/anatomia & histologia , Gordura Subcutânea/anatomia & histologia , Idoso , Glicemia , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologia
8.
Pathol Oncol Res ; 21(2): 477-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25367072

RESUMO

The correct identification of HER2-positive cases is a key point to provide the most appropriate therapy to breast cancer (BC) patients. We aimed at investigating the reproducibility and accuracy of HER2 expression by immunohistochemistry (IHC) in a selected series of 35 invasive BC cases across the pathological anatomy laboratories in Tuscany, Italy. Unstained sections of each BC case were sent to 12 participating laboratories. Pathologists were required to score according to the Food and Drug Administration (FDA) four-tier scoring system (0, 1+, 2+, 3+). Sixteen and nineteen cases were HER2 non-amplified and amplified respectively on fluorescence in situ hybridization. Among 192 readings of the 16 HER2 non-amplified samples, 153 (79.7%) were coded as 0 or 1+, 39 (20.3%) were 2+, and none was 3+ (false positive rate 0%). Among 228 readings of the 19 HER2 amplified samples, 56 (24.6%) were scored 0 or 1+, 79 (34.6%) were 2+, and 93 (40.8%) were 3+. The average sensitivity was 75.4%, ranging between 47% and 100%, and the overall false negative rate was 24.6%. Participation of pathological anatomy laboratories performing HER2 testing by IHC in external quality assurance programs should be made mandatory, as the system is able to identify laboratories with suboptimal performance that may need technical advice. Updated 2013 ASCO/CAP recommendations should be adopted as the widening of IHC 2+ "equivocal" category would improve overall accuracy of HER2 testing, as more cases would be classified in this category and, consequently, tested with an in situ hybridisation method.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica/métodos , Imuno-Histoquímica/normas , Controle de Qualidade , Receptor ErbB-2/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Reações Falso-Positivas , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Hibridização in Situ Fluorescente/normas , Itália , Patologia Clínica/normas , Guias de Prática Clínica como Assunto/normas , Receptor ErbB-2/genética , Reprodutibilidade dos Testes , Estados Unidos
9.
Br J Dermatol ; 168(3): 513-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23013061

RESUMO

BACKGROUND: Oncological research has focused on evaluating oestrogen receptors (ERs) in oestrogen-related tumours, and understanding the potential role of ERs in the pathophysiology of cancer. OBJECTIVES: To investigate the significance of oestrogen receptor beta (ERß) in melanoma. METHODS: We prospectively evaluated ERß expression in malignant melanoma (MM) tissue and adjacent healthy skin by quantitative immunohistochemistry at the Department of Dermatology of the University of Florence, from 1998 to 2010. RESULTS: ERß was detected with varying staining intensity in the 66 malignant melanocytic lesions. After adjusting for age and sex, we found that ERß expression was significantly lower in melanoma tissue compared with adjacent healthy skin (P < 0·0001). We also found significantly lower ERß levels in thick melanoma tissue compared with thin melanoma tissue. In addition, there was a positive association between Breslow thickness and the difference of ERß expression between healthy tissue and melanoma tissue (P = 0·0004). Consistent with sex differences in melanoma survival, men showed significantly lower levels of ERß than women in both melanoma (P = 0·05) and healthy tissues (P = 0·02). CONCLUSIONS: ERß expression is inversely associated with Breslow thickness and is significantly influenced by sex in MM.


Assuntos
Receptor beta de Estrogênio/fisiologia , Melanoma/etiologia , Neoplasias Cutâneas/etiologia , Análise de Variância , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Masculino , Melanoma/metabolismo , Sobrepeso/metabolismo , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Estudos Prospectivos , Fatores Sexuais , Neoplasias Cutâneas/metabolismo
10.
Endocr J ; 55(3): 439-53, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18323676

RESUMO

The recently identified gastric hormone ghrelin was initially described as a natural Growth Hormone Secretagogue Receptor ligand. Apart from ghrelin's first discovered action, which was the stimulation of Growth Hormone release, implications for many other functions have been reported. It seems that ghrelin exhibits an important role in conditions related to processes regulating nutrition, body composition and growth, as well as heart, liver, thyroid or kidney dysfunction. In this review, current available knowledge about ghrelin's role in various pathological conditions is presented.


Assuntos
Doença/etiologia , Grelina/fisiologia , Animais , Cirurgia Bariátrica , Fenômenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/metabolismo , Sistema Cardiovascular/patologia , Diabetes Mellitus/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Transtornos do Crescimento/etiologia , Hormônio do Crescimento/deficiência , Hormônio do Crescimento/metabolismo , Humanos , Fígado/patologia , Fígado/fisiologia , Neoplasias/etiologia , Obesidade/etiologia , Obesidade/cirurgia , Insuficiência Renal/etiologia , Doenças da Glândula Tireoide/etiologia
11.
Neuropediatrics ; 38(4): 200-3, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18058629

RESUMO

Megalencephaly (MEG), or enlargement of the brain, can either represent a familial variant with normal cerebral structure, or a rare brain malformation associated with developmental delay and neurological problems. MEG has been split into two subtypes: anatomical and metabolic. The latter features a build-up inside the cells owing to metabolic causes. Anatomical MEG has been detected in many different conditions, including many overgrowth syndromes. In 2004 Mirzaa et al. reported five non-consanguineous patients with a new MCA/MR syndrome characterized by severe congenital MEG with polymicrogyria (PMG), postaxial polydactyly (POLY) and hydrocephalus (HYD). The authors argued that these findings identified a new and distinct malformation syndrome, which they named MPPH. We report on a new case of MPPH, the first to be described after the original series (Mirzaa et al., 2004).


Assuntos
Encéfalo/anormalidades , Deficiências do Desenvolvimento/complicações , Hidrocefalia/complicações , Malformações do Desenvolvimento Cortical/complicações , Polidactilia/complicações , Feminino , Humanos , Hidrocefalia/patologia , Lactente , Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/patologia , Polidactilia/patologia , Tomografia Computadorizada por Raios X/métodos
12.
Phys Rev Lett ; 99(1): 010403, 2007 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-17678142

RESUMO

We produce a Bose-Einstein condensate of 39K atoms. Condensation of this species with a naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intraspecies interactions at Feshbach resonances. We explore the tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39K condensate is interesting for future experiments requiring a weakly-interacting Bose gas.

13.
Oral Dis ; 13(4): 419-25, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17577330

RESUMO

OBJECTIVE: Orofacial granulomatosis (OFG) is a rare condition characterized by non-caseating granulomas in the orofacial region. Protease-Activated Receptors (PARs) play a role in inflammatory diseases in diverse human tissues. The aim of the study was to investigate the expression of PAR-1, PAR-2, MMP-2, MMP-9, COX-1, and COX-2 in tissues taken from OFG patients. METHODS: PAR-1, PAR-2, MMP-2, MMP-9, COX-1, and COX-2 expression was evaluated by immunohistochemistry in biopsies taken from oral Crohn's disease (five cases), Melkersson-Rosenthal syndrome (MRS) (six cases), cheilitis granulomatosa (five cases) and normal oral mucosa (five cases). RESULTS: PAR-1 was observed in mononuclear inflammatory cells in edematous/lichenoid lesions, whereas a strong PAR-2 immunostaining was detected in epithelioid histiocytes and giant cells in granulomatous lesions, irrespective of the clinical features (Crohn vs MRS). MMPs and COX-2 were expressed in the inflammatory component of edematous/lichenoid lesions and markedly overexpressed in granulomatous lesions. COX-1 was weakly and variably expressed in both edematous/lichenoid and granulomatous lesions. CONCLUSION: Thus, PAR-1 and PAR-2 expressions were related to the intensity and type of inflammatory response but not to the type of clinical lesion. Simultaneous overexpression of PARs, MMPs and COXs suggests synergism among these proinflammatory receptors and enzymes.


Assuntos
Granulomatose Orofacial/patologia , Receptor PAR-1/análise , Receptor PAR-2/análise , Adolescente , Adulto , Idoso , Criança , Doença de Crohn/patologia , Ciclo-Oxigenase 1/análise , Ciclo-Oxigenase 2/análise , Edema/patologia , Células Epitelioides/patologia , Feminino , Células Gigantes/patologia , Histiócitos/patologia , Humanos , Leucócitos Mononucleares/patologia , Erupções Liquenoides/patologia , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Síndrome de Melkersson-Rosenthal/patologia , Pessoa de Meia-Idade , Doenças da Boca/patologia , Mucosa Bucal/patologia , Estudos Retrospectivos
14.
Biochim Biophys Acta ; 1763(5-6): 442-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16750865

RESUMO

Recent data shed light on two novel aspects of the mitochondria-Ca2+ liaison. First, it was extensively investigated how Ca2+ handling is controlled by mitochondrial shape, and positioning; a playground also of cell death and survival regulation. On the other hand, significant progress has been made to explore how intra- and near-mitochondrial Ca2+ signals modify mitochondrial morphology and cellular distribution. Here, we shortly summarize these advances and provide a model of Ca2+-mitochondria interactions.


Assuntos
Sinalização do Cálcio , Mitocôndrias/metabolismo , Animais , Evolução Biológica , Retículo Endoplasmático/metabolismo , Humanos
16.
Phys Rev Lett ; 94(18): 183201, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15904366

RESUMO

We have observed Feshbach resonances in collisions between ultracold 52Cr atoms. This is the first observation of collisional Feshbach resonances in an atomic species with more than one valence electron. The zero nuclear spin of 52Cr and thus the absence of a Fermi-contact interaction leads to regularly spaced resonance sequences. By comparing resonance positions with multichannel scattering calculations we determine the s-wave scattering length of the lowest (2S+1)Sigma(+)(g) potentials to be 112(14) a(0), 58(6) a(0), and -7(20) a(0) for S=6, 4, and 2, respectively, where a(0)=0.0529 nm.

17.
Arch Ital Biol ; 143(1): 1-12, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15844665

RESUMO

In the present experiment the instruction to relax was given to awake highly (Highs) and non hypnotizable subjects (Lows), while their heart rate, respirogram and skin resistance were recorded together with electroencephalogram, electroculogram and corrugator electromiogram. At the beginning of the experiment, Highs exhibited no significant difference in heart rate (HR), respiratory frequency (RF) and heart rate variability (HRV) with respect to Lows, but showed a higher EEG alpha and theta1 power. During the session, both groups decreased their heart rate, but changes were significant only in Lows, which increased significantly also the parasympathetic component of their HRV (high frequency, HF). In both groups, EEG showed alpha, beta2 and theta2 power decrements; theta1 activity decreased only in Lows, while gamma power increased in Highs and decreased in Lows. Results suggest that Highs and Lows used different cognitive strategies in the elaboration of the relaxation request and that Highs performed the task through a higher integrative activity.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Córtex Cerebral/fisiologia , Cognição/fisiologia , Estado de Consciência/fisiologia , Relaxamento/fisiologia , Adolescente , Adulto , Eletroencefalografia , Eletroculografia , Feminino , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Hipnose , Masculino , Fenômenos Fisiológicos Respiratórios , Sugestão
18.
Phys Rev Lett ; 94(10): 103201, 2005 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-15783485

RESUMO

We employ radio-frequency spectroscopy on weakly bound (6)Li(2) molecules to precisely determine the molecular binding energies and the energy splittings between molecular states for different magnetic fields. These measurements allow us to extract the interaction parameters of ultracold (6)Li atoms based on a multichannel quantum scattering model. We determine the singlet and triplet scattering lengths to be a(s) = 45.167(8)a(0) and a(t) = -2140(18)a(0) (1a(0) = 0.052 917 7 nm), and the positions of the broad Feshbach resonances in the energetically lowest three s-wave scattering channels to be 83.41(15), 69.04(5), and 81.12(10) mT.

19.
Biochim Biophys Acta ; 1660(1-2): 164-70, 2004 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-14757232

RESUMO

Human red blood cells (RBC) can be studied by means of whole-cell and nystatin-perforated patch-clamp techniques. In 85% of the whole-cell experiments (n=86) and 69% of the perforated-patch recordings (n=13), steps to positive potentials, from a holding potential of 0 mV, induced a slow-activating non-inactivating persistent outward current which reverted at about 0 mV. The current activation phase fitted well with a two-component exponential curve. Half-maximal conductance was reached at about 42 mV. Na+ and K+ carried this current, which was not affected by 20 nM charybdotoxin or 20 mM TEA, but was reduced following a partial substitution of extracellular Cl- by tartrate. This current has characteristics similar to the single-channel currents already described in RBC and may be involved in the rapid adaptations of these cells in the circulation.


Assuntos
Eritrócitos/química , Canais Iônicos/química , Cloretos/farmacologia , Humanos , Potenciais da Membrana , Nistatina , Técnicas de Patch-Clamp
20.
Phys Rev Lett ; 91(19): 193201, 2003 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-14611578

RESUMO

We have measured the deca-triplet s-wave scattering length of the bosonic chromium isotopes 52Cr and 50Cr. From the time constants for cross-dimensional thermalization in ultracold atomic samples, we have determined the magnitudes |a(52Cr)|=(170+/-39)a(0) and |a(50Cr)|=(40+/-15)a(0), where a(0)=0.053 nm. By measuring the rethermalization rate of 52Cr over a wide temperature range and comparing the temperature dependence with the effective-range theory and numerical single-channel calculations, we have obtained strong evidence that the sign of a(52Cr) is positive. Rescaling our 52Cr model potential to 50Cr strongly suggests that a(50Cr) is positive also.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA