5,334 research outputs found
Analisi Morfometrica dei Cromosomi del Coniglio (Oryctolagus Cuniculus L.)
RIASSUNTOSono stati studiati i cromosomi di coniglio (Oryctolagus cuniculus L.).Il numero diploide dei cromosomi in cellule somatiche e risultato di 2 n= 44. L'analisi morfologica e metrica di essi ha permesso la distinzione in gruppi di cromosomi affini. Una tale classificazione si pensa possa essere utile in ricerche di cariologia comparata nell'ambito dei Leporidae
A New Configuration of Vertical Axis Wind Turbine: Towards the Development of a highly distributed and efficient Wind Power Generation
Preliminary results obtained for a new configuration lift based vertical-axis wind turbine are shown. The turbine rotor is a cross flow fan type made with high curvature aerodynamic profiles. A reduced scale model of the turbine rotor has been designed and preliminary tested at the Department of Aerospace Engineering of the University of Pisa (rotor diameter 250 mm, rotor height 210 mm). The reduced scale model shows an efficiency of about eighteen per cent. The rotor is of a self-starting type. Two-dimensional CFD analyses have been performed applying both the Moving Reference Frame and the Moving Mesh conditions to the grid which surrounds the rotor blades (Fluent® Rel. 6.3 and STAR-CCM+® Rel. 6.04 have been used). Noticeable scale effects have been found numerically, so, the efficiency of a full scale lift based vertical axis multi-blades optimized wind turbine is expected to be comparable with lift based horizontal-axis wind turbines
Gastaut type-idiopathic childhood occipital epilepsy and childhood absence epilepsy: a clinically significant association?
We report an unusual association between idiopathic occipital epilepsy and childhood absence epilepsy
in 2 pediatric patients. At first clinical and electroencephalographic evaluation, the patients presented
the peculiar signs of idiopathic occipital epilepsy Gastaut type: focal sensory visual seizures, migrainelike
symptoms (only in one patient) and unilateral spike–wave discharges over occipital regions. Both
children were treated with valproic acid and their seizures were rapidly controlled. After a seizure-free
period, the patients presented typical absence with ictal electroencephalographies showing 3 cycles/s
generalized and symmetrical spike–wave complexes. We discuss the possible association between these
two epileptic syndromes and its common pathophysiological mechanisms
Theoretical status of Bs-mixing and lifetimes of heavy hadrons
We review the theoretical status of the lifetime ratios τB+/τBd, τBs/τBd, τΛb/τBd and τBc and of the mixing quantities ΔMs, ΔΓs and ϕs. ΔMs and ΔΓs suffer from large uncertainties due to the badly known decay constants, while the ratio ΔΓs/ΔMs can be determined with almost no non-perturbative uncertainties, therefore it can be used perfectly to find possible new physics contributions in the mixing parameters. We suggest a very clear method of visualizing the bounds on new physics and demonstrate this by combining the latest experimental numbers on the mixing quantities quantities with theory – one already gets some hints for new physics contributions, but more precise experimental numbers are needed to draw some definite conclusions. We conclude with a ranking list of all the discussed quantities according to their current theoretical uncertainties and point out possible improvements
Managment of diabetic ketoacidosis in children and adolescents in sub-Saharan Africa: A review
Background: Diabetic ketoacidosis (DKA) is a complex metabolic state of hyperglycaemia, ketosis, and acidosis. Diabetes in sub-Saharan Africa is, in many patients a serious disease with a poor prognosis. Most deaths, however, are due to preventable causes.Objective: To improve knowledge on the management of DKA in sub-Saharan Africa.Data sources: Literature review from different published sources. Data synthesis: Health systems in sub-Saharan Africa are currently organised for the treatment of episodes of illness and not long-term conditions like diabetes. Therefore the high rates of DKA is essentially due to lack of training of health professionals, lack of facilities in most hospitals, lack of public awareness as well as lack of health education to individual patients/families. In addition erratic insulin supply coupling with infections, low parental education, poor insulin storage and lack of facilities for self monitoring of blood glucose.Conclusion: A complex unfavourable social and economic environment is the basis of the high prevalence of DKA in sub-Saharan Africa. Several episodes of DKA can be prevented by effective public awareness programmes and education to healthcare providers
Cognitive and linguistic abnormalities in benign childhood epilepsy with centrotemporal spikes
Aim: To assess the cognitive function and language ability in children with benign
partial epilepsy with centrotemporal spikes.
Methods: Twenty-five patients with benign partial epilepsy with centrotemporal
spikes were included. They were divided into two subgroups. Group I: 10 patients with rolandic
focus who were not treated. Group II: 15 patients with rolandic focus receiving treatment.
A third Group of 12 healthy subjects have been studied. All children underwent
standardized neuropsychological testing: electroencephalogram recording, Wechsler Intelligence
Scale for Children-revised, Peabody Picture Vocabulary Test-III (PPVT-III) and Boston
Naming Test (BNT), both during active disease (T1) and 2 years after recovery from epilepsy
(T2).
Results: At T1 evaluation, no significant differences in group I and II patients about
general intelligence, when compared with controls, were found. Group I and II patients
were impaired with respect to controls in the receptive and expressive vocabulary evaluated
with PCVT-III and BNT, respectively. At T2 evaluation, group I and II patients showed a normalization
of the language abnormalities.
Conclusion: Deficits of speech-related abilities can be detected in children with this type of epilepsy:
these dysfunctions seem to be independent of the effects of antiepileptic treatment and are
reversible after remission of epilepsy
An alternative approach of TUNEL assay to specifically characterize DNA fragmentation in cell model systems
DNA damage is one of the most important effects induced by chemical agents. We report a comparative analysis of DNA fragmentation on three different cell lines using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, generally applied to detect apoptosis. Our approach combines cytogenetic techniques and investigation in detached cellular structures, recovered from the culture medium with the aim to compare the DNA fragmentation of three different cell line even beyond the cells adherent to substrate. Consequently, we detect any fragmentation points on single chromosomes, whole nuclei and other cellular structures. Cells were exposed to resveratrol (RSV) and doxorubicin (Doxo), in single and combined treatments. Control and treated astrocytes showed DNA damage in condensed nuclei and detached structures. Caco-2 cells showed fragmented DNA only after Doxo-treatment, while controls showed fragmented chromosomes, indicating DNA damage in replicating cells. MDA-MB-231 cells showed nuclear condensation and DNA fragmentation above all after RSV-treatment and related to detached structures. This model proved to perform a grading of genomic instability (GI). Astrocytes show a hybrid level of GI. Caco-2 cells showed fragmented metaphase chromosomes, proving that the DNA damage was transmitted to the daughter cells probably due to an absence of DNA repair mechanisms. Instead, MDA-MB-231 cells showed few or no fragmented metaphase, suggesting a probable activation of DNA repair mechanisms. By applying this alternative approach of TUNEL test, we obtained data that can more specifically characterize DNA fragmentation for a suitable application in various fields
Experiencia didáctica con dinosaurios
Esta experiencia se realizo en la ciudad La Plata en el año 2002 en el Parque Ecológico de esa ciudad luego en el 2003, nos invitaron a participar en la institución, La Republica de los Niños de dicha ciudad, hasta mediados de 2008. La experiencia estuvo dirigida a niños entre 4 y 10 años, ofreciendo una visión sobre nuevas teorías, descripción de los diferentes taxones, procesos evolutivos de los diferentes grupos, creímos conveniente introducir otros temas relacionados, como Deriva continental, extinción de las distintas familias de dinosaurios, etc. El Taller se llevó a cabo en tres etapas: Una exposición oral, tratando principales temas como el origen de los dinosaurios, los diferentes cambios del planeta Tierra en esos períodos (tanto geográfica como climáticamente), hasta llegar a la extinción del grupo. Una segunda etapa, tratamos mediante un experimento, demostrar procesos de fosilización de estos grupos, la ultima parte de este taller, se enfoco en explicar el trabajo del paleontólogo en el campo y luego en laboratorio, esta sección era una de las mas importantes, padres y niños trabajaban juntos. El taller contó con la presencia de más de cinco mil niños y varias participaciones a diferentes establecimientos escolares y centros culturales de La Plata, Ensenada, Berisso y conurbano bonaerense.Trabajos del área Ciencias NaturalesDepartamento de Ciencias Exactas y Naturale
Medicina dell’adolescenza
L’Organizzazione Mondiale della Sanità definisce come “adolescenti” le persone di età compresa tra 10 e 19 anni. Questi minori rappresentano circa il 10-25% della popolazione a seconda dei vari paesi europei (www.euro.who.int) e poco più del 9,0% in Italia al 1° gennaio 2023 (www.istat.it). Nel nostro Paese si osserva inoltre una rapida contrazione dei soggetti in età adolescenziale in conseguenza del progressivo calo delle nascite; ad esempio, si ha una riduzione di oltre l’8% (-47.165 unità) dei bambini di 10 anni rispetto ai ragazzi di 18 anni. Una prima ovvia considerazione a questo dato di fatto è la necessità di assicurare il migliore stato possibile a questa fascia di età anche in prospettiva futura. In effetti, la maggior parte degli adolescenti in Europa è sana, ma ogni giorno oltre 3.000 di loro muoiono per cause prevenibili o curabili. Inoltre, gli adolescenti presentano cause specifiche di morbilità [lesioni non intenzionali o intenzionali, disturbi della salute mentale (depressione, abuso di sostanze, disturbi alimentari), malattie infettive, comportamenti sessuali a rischio, gravidanza e parto precoci] con conseguenze sia a breve che a lungo termine (Slobođanac M., et al. www.eapaediatrics.eu/young-eap-eap-july-2019-blog-adolescent-medicine-and-health-a-training-challenge-for-europe/).
Ne deriva la necessità di percorsi formativi dedicati pre-laurea e post-laurea, compresi quelli di educazione medica continua, in Medicina dell’adolescenza. Alcuni paesi (USA, Canada, Australia) hanno riconosciuto le esigenze specifiche di salute degli adolescenti, creando percorsi formativi anche specialistici in questo nuovo settore medico
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