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1.
Phys Rev E ; 107(5-2): 055203, 2023 May.
Article in English | MEDLINE | ID: mdl-37328974

ABSTRACT

External kink modes, believed to be the drive of the ß-limiting resistive wall mode, are strongly stabilized by the presence of a separatrix. We thus propose a novel mechanism explaining the appearance of long-wavelength global instabilities in free boundary high-ß diverted tokamaks, retrieving the experimental observables within a physical framework dramatically simpler than most of the models employed for the description of such phenomena. It is shown that the magnetohydrodynamic stability is worsened by the synergy of ß and plasma resistivity, with wall effects significantly screened in an ideal, i.e., with vanishing resistivity, plasma with separatrix. Stability can be improved by toroidal flows, depending on the proximity to the resistive marginal boundary. The analysis is performed in tokamak toroidal geometry, and includes averaged curvature and essential separatrix effects.

2.
Phys Rev Lett ; 122(15): 155003, 2019 Apr 19.
Article in English | MEDLINE | ID: mdl-31050499

ABSTRACT

The excitation mechanism for low-n edge harmonic oscillations in quiescent H-mode regimes is identified analytically. We show that the combined effect of diamagnetic and poloidal magnetohydrodynamic flows, with the constraint of a Doppler-like effect of the ion flow, leads to the stabilization of short wavelength modes, allowing low-n perturbation to grow. The analysis, performed in tokamak toroidal geometry, includes the effects of large edge pressure gradients, associated with the local flattening of the safety factor and diamagnetic flows, sheared parallel and E×B rotation, and a vacuum region between plasma and the ideal metallic wall. The separatrix also is modeled analytically.

3.
Biochim Biophys Acta Mol Basis Dis ; 1864(6 Pt A): 2131-2142, 2018 06.
Article in English | MEDLINE | ID: mdl-29601977

ABSTRACT

Leigh syndrome (LS) associated with cytochrome c oxidase (COX) deficiency is an early onset, fatal mitochondrial encephalopathy, leading to multiple neurological failure and eventually death, usually in the first decade of life. Mutations in SURF1, a nuclear gene encoding a mitochondrial protein involved in COX assembly, are among the most common causes of LS. LSSURF1 patients display severe, isolated COX deficiency in all tissues, including cultured fibroblasts and skeletal muscle. Recombinant, constitutive SURF1-/- mice show diffuse COX deficiency, but fail to recapitulate the severity of the human clinical phenotype. Pigs are an attractive alternative model for human diseases, because of their size, as well as metabolic, physiological and genetic similarity to humans. Here, we determined the complete sequence of the swine SURF1 gene, disrupted it in pig primary fibroblast cell lines using both TALENs and CRISPR/Cas9 genome editing systems, before finally generating SURF1-/- and SURF1-/+ pigs by Somatic Cell Nuclear Transfer (SCNT). SURF1-/- pigs were characterized by failure to thrive, muscle weakness and highly reduced life span with elevated perinatal mortality, compared to heterozygous SURF1-/+ and wild type littermates. Surprisingly, no obvious COX deficiency was detected in SURF1-/- tissues, although histochemical analysis revealed the presence of COX deficiency in jejunum villi and total mRNA sequencing (RNAseq) showed that several COX subunit-encoding genes were significantly down-regulated in SURF1-/- skeletal muscles. In addition, neuropathological findings, indicated a delay in central nervous system development of newborn SURF1-/- piglets. Our results suggest a broader role of sSURF1 in mitochondrial bioenergetics.


Subject(s)
Central Nervous System/growth & development , Disease Models, Animal , Leigh Disease/genetics , Membrane Proteins/genetics , Mitochondrial Proteins/genetics , Sus scrofa/genetics , Animals , Animals, Genetically Modified , Animals, Newborn , Behavior, Animal , CRISPR-Cas Systems , Cells, Cultured , Down-Regulation , Electron Transport Complex IV/metabolism , Female , Fibroblasts , Gene Editing , Gene Knockout Techniques , Humans , Jejunum/pathology , Leigh Disease/pathology , Male , Mitochondria/pathology , Muscle, Skeletal/cytology , Muscle, Skeletal/pathology , Nuclear Transfer Techniques , Primary Cell Culture
4.
Pediatr Obes ; 13(2): 81-87, 2018 02.
Article in English | MEDLINE | ID: mdl-27900849

ABSTRACT

BACKGROUND: Technological instruments may help control paediatric obesity. OBJECTIVE: We tested whether a personalized programme based on the energy expenditure obtained from a wristband (WB) and the energy intake obtained from a smartphone application (APP) is superior to a standard approach at promoting weight loss. METHODS: We performed a randomized controlled trial in obese children aged 10-17 years. The experimental (EXP) and control (CTR) groups were given a low-energy diet and a prescription for physical activity. The EXP group was equipped with a WB and an APP and given personalized feedback every 7 days. The main outcome was weight loss at 3 months. RESULTS: The mean (standard deviation) z-score of body mass index at the enrollment was 2.20 (0.47) in the EXP (n = 16 out of 23) and 2.09 (0.34) in the CTR group (n = 14 out of 20) of children who completed the trial. The mean (95%CI) difference in weight loss at 3 months was 0.07 kg (95%CI: 2.81 to 2.96) for EXP vs. the CTR. CONCLUSION: A personalized lifestyle programme based on a WB and an APP was not superior to a standard lifestyle programme at promoting weight loss in obese children.


Subject(s)
Caloric Restriction/methods , Exercise Therapy/methods , Pediatric Obesity/therapy , Smartphone , Weight Reduction Programs/methods , Adolescent , Child , Energy Intake , Energy Metabolism , Exercise , Female , Humans , Life Style , Male , Mobile Applications
5.
Theriogenology ; 73(6): 748-57, 2010 Apr 01.
Article in English | MEDLINE | ID: mdl-19726075

ABSTRACT

The culture of early embryos in the surrogate xeno-oviduct was first developed in the early 1950s to allow transport of embryos at long distances. Later, it was applied to the study of culture requirements of the early embryo especially that of bovine origin. In this article, we review the data available on the culture of in vitro-matured and in vitro-fertilized embryos of Bos taurus, Sus scrofa, Equus caballus and Ovis aries in the surrogate sheep oviduct compared with data on in vitro culture in different media. Short-term and long-term cellular and molecular effects are described mainly for the bovine species where more extensive use of this technique has been made. A comparison with in vitro culture in various conditions and species indicate that embryos cultured in the sheep oviduct have close similarities to totally in vivo-derived embryos. The data provided demonstrate that the technique of in vivo culture in the surrogate sheep oviduct is versatile and allows a high rate of embryonic development in all species examined.


Subject(s)
Cattle/embryology , Embryo Culture Techniques/veterinary , Fallopian Tubes , Horses/embryology , Sheep/embryology , Swine/embryology , Animals , Embryo Culture Techniques/methods , Embryonic Development , Female , Fertilization in Vitro/veterinary
6.
Rays ; 25(4): 429-46, 2000.
Article in English | MEDLINE | ID: mdl-11367912

ABSTRACT

Problems concerning the use of different imaging modalities in N staging of the neck are dealt with. The peculiar features, findings, sensitivity, specificity and diagnostic accuracy of each modality in the diagnosis of nature of cervical lymphadenopathy are described, as reported in most recent reports of literature, and according to the personal experience. CT/MRI criteria commonly used to establish whether a lymph node is metastatic or benign/reactive are related to the size, morphology, density (CT), signal intensity (MRI), evidence of central necrosis and extracapsular spread. Color Doppler US is a reliable method in the diagnosis of cervical metastatic lymphadenopathy even if no parameter is highly predictive; the combination of different findings, especially cortical thickening and structural inhomogeneity with thin, compressed, displaced or non visualized hilum makes the procedure significantly sensitive and specific. Intranodal hilar vascularization on color Doppler, with high resistance arterial flow (PI > 1.5), enhances the predictive value of findings of bi-dimensional sonography. Extracapsular spread impacts on survival as well as on the number of recurrences, which increases in patients with extracapsular spread; the disease-free interval is less in these patients. The identification and definition of extracapsular spread is based on some CT/MRI criteria as: 1) lymph nodes with spiky, irregular margins; 2) loss of adipose cleavage planes around the node and thickening of adjacent fascia; 3) apparent invasion of an adjacent structures or muscles. Similarly to CT/MR, sonographic findings of extracapsular spread can be: 1) blurred margins and irregular contours; 2) invasion of an adjacent structure or muscle.


Subject(s)
Diagnostic Imaging , Head and Neck Neoplasms/pathology , Lymphatic Diseases/diagnosis , Lymphatic Metastasis/diagnosis , Humans
7.
Anticancer Res ; 18(4B): 2811-4, 1998.
Article in English | MEDLINE | ID: mdl-9713466

ABSTRACT

A one-page family history questionnaire was validated in two European areas covered by population-based cancer registries. Information on malignant tumor occurrence in first degree relatives was collected from 193 cancer patients in Trieste, Italy and from 64 in Basel, Switzerland. They were then compared with the corresponding data stored in the registries' files. The sensitivity of the questionnaire was 85% (Trieste) and 74% (Basel), the specificity was 97% in both studies and the overall accuracy 95% (Trieste) and 94% (Basel). The questionnaire is recommended for use in different geographical areas covered by population based registries for comparative analyses of cancer related family histories.


Subject(s)
Family Health , Neoplasms/epidemiology , Surveys and Questionnaires , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Pilot Projects , Reproducibility of Results , Sensitivity and Specificity
8.
J Clin Psychol ; 54(2): 143-53, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9467758

ABSTRACT

Differences in Minnesota Multiphasic Personality Inventory-2 (MMPI-2) response latencies between groups instructed to respond honestly or fake were explored. There were 120 undergraduate students who completed a computer administered MMPI-2 with instructions to either respond honestly, to underreport psychopathology, or to overreport psychopathology. Results showed that subjects required significantly more time to respond in a manner that was inconsistent with their response set when pattern of endorsement (acceptance vs. rejection) was considered and less time when pattern of endorsement was not considered. The differential response of subjects across groups suggests that response latencies are related to response styles and that future research may indicate a methodology for utilizing response latencies in assessing response validity.


Subject(s)
MMPI , Psychometrics , Truth Disclosure , Analysis of Variance , Female , Humans , Male , Reaction Time , Reproducibility of Results
9.
Int J Cancer ; 73(6): 822-7, 1997 Dec 10.
Article in English | MEDLINE | ID: mdl-9399659

ABSTRACT

We conducted a population-based cohort study in the province of Trieste, Italy, to assess whether the first-degree relatives of children with malignancies had an increased risk of cancer compared with the general population. We examined cancers occurring in all first-degree relatives of children who experienced malignancies under the age of 15 years between 1971 and 1993 (probands). A cohort of the 394 relatives of the 125 probands contributed 7,939 person-years of observation. Among the relatives as a whole, we found a statistically significant increased risk of developing all malignancies except non-melanoma skin carcinoma (21 observed relatives with cancer and 12.46 expected, for a standardized incidence ratio [SIR] of 1.69), of developing breast cancer (SIR = 3.09) and of developing haemolymphatic system neoplasms (SIR = 4.03). This was mainly due to the excess cancer risk in the relatives of probands with intracranial tumours, who showed a significant 3.1-fold risk for developing all cancers but non-melanoma skin tumours. Our findings and the previously reported steep rise in the incidence of childhood brain tumours in our area may imply that not only genetic factors but also shared environmental agents might be involved in the observed aggregation of cancer in the families of probands with intracranial tumours.


Subject(s)
Leukemia/epidemiology , Leukemia/genetics , Neoplasms/epidemiology , Neoplasms/genetics , Adolescent , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Infant, Newborn , Italy/epidemiology , Leukemia/etiology , Male , Neoplasms/etiology , Neurofibromatosis 1/etiology , Neurofibromatosis 1/genetics , Nuclear Family , Pedigree , Risk Factors , Xeroderma Pigmentosum/genetics
10.
Epidemiol Prev ; 21(3): 202-10, 1997.
Article in Italian | MEDLINE | ID: mdl-9424437

ABSTRACT

The study objectives were: 1) to analyse the incidence and death rates from cancer among children aged 0-14 years resident in the north-eastern Italian province of Trieste between 1972-1993, using data from the population-based Trieste Cancer Registry; 2) to evaluate the local diagnostic facilities by analysing the accuracy of histological diagnoses, the causes of delay in the diagnosis, and the interval between onset of symptoms and diagnosis of cancer; 3) to calculate the proportion of patients treated following the most effective therapy protocols known at the time of the tumour detection, and to compute the actuarial five-year survival rates since diagnosis. We recorded 123 new cases of cancer (93% microscopically verified) corresponding to a rate, age-standardized to the world population, of 161.9 (standard error [SE] = 15.1) per million child-years. The most common diagnostic group was that of primary brain tumours: 40 cases, rate = 51.0 (SE = 8.4). In 102 cases the diagnosis was made at hospitals in the province of Trieste, with a median time of seven days (25th-75th percentile = 1-16) between admission and diagnosis. In 37 cases the length of the interval between the advancing of the diagnostic hypothesis of cancer and the microscopic diagnosis ranged from eight to 57 days: 20% of the interval was spent in the identification of the lesion, 50% elapsed between the identification and the biopsy, and 30% was spent in performing the microscopic diagnosis. Out of 123 cases, 30 were partly treated or completely treated at centres not located in our province, i.e., at seven different Italian hospitals (14 cases), nine European hospitals (15 cases), and at one North-American centre (one case). The 40 children with brain tumours were spread among 12 institutions. The five-year survival rate increased from 52.4% (SE = 6.3) for the 63 children with cancers diagnosed in 1972-1981 to 62.5% (SE = 7.0) for the 48 with malignancies detected in 1982-1990.


Subject(s)
Neoplasms/epidemiology , Quality of Health Care/statistics & numerical data , Adolescent , Child , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , Italy/epidemiology , Male , Mortality/trends , Neoplasms/diagnosis , Neoplasms/therapy , Registries/statistics & numerical data
11.
J Pers Assess ; 65(2): 278-99, 1995 Oct.
Article in English | MEDLINE | ID: mdl-16367719

ABSTRACT

This article presents a review and critique of research on the Minnesota Multiphasic Personality Inventory (MMPI) subtle items in regard to their validity as measures of their scales' characteristics. The main categories of focus are their convergent and discriminative validity, the paradoxical effect, and the issue of whether removing these items would improve MMPI validity. Important problems in the methodologies are noted and discussed in some detail. These methodological concerns and the conflicting results across studies obscure firm conclusions on the validity of the subtle items, although strong support is lacking. However, more evidence is needed before deciding to remove these items from the MMPI; therefore, this article provides recommendations for future research.

12.
Urology ; 43(2): 235-7, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8116122

ABSTRACT

Bilateral renal artery thrombosis is a rare but traumatic injury that is most commonly caused by sudden deceleration. Traditional methods of repair (e.g., in situ repair, bypass graft, and thrombectomy) have poor success rates. This report is the first successful use of autotransplantation in a patient with bilateral renal artery thrombosis.


Subject(s)
Kidney Transplantation/methods , Renal Artery Obstruction/surgery , Renal Artery/injuries , Thrombosis/surgery , Adult , Deceleration/adverse effects , Humans , Kidney/injuries , Male , Renal Artery Obstruction/etiology , Suicide, Attempted , Thrombosis/etiology , Transplantation, Autologous
13.
Behav Res Ther ; 30(5): 513-20, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1520237

ABSTRACT

Cognitive processing of pain and fear information was examined using a methodology based on the bioinformational theory of emotion. Undergraduate volunteers (n = 48) participated in an imagery assessment procedure involving audio presentation of pain, fear, or pain plus fear experimental scripts. Action and neutral scripts were presented as control stimuli. Heart rate and self-reported affective judgements were assessed. Results indicated that pain scripts were rated more negatively, and were associated with feelings of less dominance than the other experimental scripts. Fear scripts elicited greater heart rate acceleration than either pain or pain plus fear scripts. The direction of physiological and verbal response to pain scripts and fear scripts, however, was very similar, differing only in amplitude; greater heart rate response and more negative ratings were manifested relative to action or neutral scripts.


Subject(s)
Arousal , Fear , Imagination , Pain/psychology , Adolescent , Adult , Female , Heart Rate , Humans , Male , Middle Aged
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