Genetic characterization of Libyan date palm resources by microsatellite markers.

Molecular typing of 377 female date palm trees belonging to 18 Libyan cultivars and representing common genotypes in the central Libyan oasis of Al Jufrah was performed using 16 highly polymorphic microsatellite or SSR loci. A total of 110 alleles with an average of 6.88 alleles per locus were scored indicating the high level of polymorphism existing among the cultivars thus allowing their genetic fingerprinting. Moreover 28 alleles out of 110 were fixed. All the cultivars were characterized by negative values of the Fixation Index (F) due to an excess of heterozygotes with respect to HW equilibrium. The pattern of genetic diversity among cultivars was estimated by codominant genetic distances and presented by principal coordinates analysis (PCoA). The observed pattern evidences the genetic diversity existing among cultivars that allow distinguishing them easily. The average dissimilarity internal to each cultivar ranged from 0 to 21. Seven cultivars showed value zero indicating no genetic difference within cultivar in agreement with their Fixation Index (F = 1). A varietal identification key was also built using multiloci genotyping with only three microsatellite loci that identified 23 alleles in total. The possibility to attribute the unknown male plant to a cultivar was also considered and male parentage analysis was performed. Fifty-five male plants out of 63 were assigned to a definite cultivar with high confidence level. The positive result obtained in identifying males confirmed the suitability of SSR for clone fingerprinting and cultivar identification, thus opening new prospects for date palm breeding.

Negative specific heat in the canonical statistical ensemble.

According to thermodynamics, the specific heat of Boltzmannian short-range interacting systems is a positive quantity. Less intuitive properties are instead displayed by systems characterized by long-range interactions. In that case, the sign of specific heat depends on the considered statistical ensemble: Negative specific heat can be found in isolated systems, which are studied in the framework of the microcanonical ensemble; on the other hand, it is generally recognized that a positive specific heat should always be measured in systems in contact with a thermal bath, for which the canonical ensemble is the appropriate one. We demonstrate that the latter assumption is not generally true: One can, in principle, measure negative specific heat also in the canonical ensemble if the system under scrutiny is non-Boltzmannian and/or out-of-equilibrium.

Characterizing dynamics with covariant Lyapunov vectors.

A general method to determine covariant Lyapunov vectors in both discrete- and continuous-time dynamical systems is introduced. This allows us to address fundamental questions such as the degree of hyperbolicity, which can be quantified in terms of the transversality of these intrinsic vectors. For spatially extended systems, the covariant Lyapunov vectors have localization properties and spatial Fourier spectra qualitatively different from those composing the orthonormalized basis obtained in the standard procedure used to calculate the Lyapunov exponents.

Ambulatory conservative hemodynamic management of varicose veins: critical analysis of results at 3 years.

This report describes the results of our 3-year experience using ambulatory conservative hemodynamic management (ACHM) for lower extremity venous insufficiency involving the greater saphenous vein (GSV), with specific analysis of recurrence due to neoformation of vessels. We performed 289 ACHM procedures in 259 consecutive patients with GSV-related varicose veins. Follow-up clinical examination and Doppler ultrasound imaging was carried out at 3, 6, 12, 24, and 36 months in all cases to assess formation of neovessels supplied either by the superficial (A) or deep (B) venous system. Our data showed that ACHM achieved excellent improvement, with complete disappearance of varicose veins in 41.2% of cases, good improvement in 43%, fair improvement in 14.1%, and no improvement in 1.7%. The only predictor of outcome was the quality of drainage from the GSV vein. Poor drainage leads to neoformation of vessels supplied by the superficial (A) venous system. In about 50% of cases, drainage appeared spontaneously within 1 year, with a subsequent reduction in formation of neovessels. Neoformation of vessels supplied by the deep (B) venous system (10%) was independent of the quality drainage. This finding suggests that formation of these neovesseis is unrelated to the surgical method used to treat varicose veins. In patients with poor drainage of the saphenous network, neoformation of vessels supplied by the superficial (A) venous system is predictable with regard to both topography and delay. ACHM is a good tool for treatment of varicose veins, as reliable statistical prediction of mid-term results is possible using available models.

[Comparison between the CHIVA cure and stripping in the treatment of varicose veins of the legs: follow-up of 3 years]. / Comparaison entre cure C.H.I.V.A. et stripping dans le traitement des veines variqueuses des membres inférieurs: suivi de 3 ans.

OBJECTIVE: To assess three-year results following "CHIVA". DESIGN: Comparison between our results and data in the literature following stripping. SETTING: Phlebologic Surgery, 46 Datini Street, Florence, Italy. PATIENTS: 148 consecutive operated patients suffering from varicose veins (166 procedures). INTERVENTIONS: "CHIVA", as described by Franceschi and Bailly. MAIN OUTCOME MEASURES: The presence of visible varicose veins, graded in three categories, according to Hobbs and Einarsson, as shown by clinical examination. RESULTS: Very good results were obtained in 100 cases, who presented without any finding of varicose veins throughout the follow-up. Of the remaining 66, in 1 case we found a new varicose network completely developed, whereas in 65 cases only some visible residual or recurrent vessels were present. CONCLUSIONS: Significantly better results were observed in the CHIVA group compared with stripping groups (P < 0,001).

[The nimodipine therapy of acute focal cerebral ischemia (minor stroke). A clinical study with an assessment of regional cerebral blood flow by SPECT]. / Terapia con nimodipina dell'ischemia cerebrale acuta a focolaio (minor stroke). Studio clinico con valutazione del flusso cerebrale regionale tramite SPECT.

Aim of the study is the evaluation of therapeutic effectiveness of nimodipine in acute focal cerebral ischaemia. Thirty patients affected by minor ischaemic stroke divided in two randomized groups have been studied consecutively: all the patients were treated with standard therapy, nimodipine was delivered in addition only to the patients of the first group. Both clinical evaluation using Mathew scale, modified by Gelmers, and flowmetric evaluation with SPECT were performed at different times. The results haven't shown any significant statistical difference in the effectiveness of the therapy between the two groups even if a positive clinical trend was evidenced in the group treated with nimodipine. The flowmetric study has shown the poor homogeneity of the groups from a physiopathological point of view not-with-standing the two groups were similar for the clinical severity, sex, age and vascular risk factors. We conclude that is advisable to carry out further trials in which the comparison study groups are more numerous and balanced also from a physiopathological point of view.

Exposure to carcinogenic chemicals and smoking increases urinary excretion of mutagens in humans.

Urine samples from a control population and from a population of chemical workers from two chemical plants near Florence, Italy, were analyzed for the presence of mutagenic chemicals by the Salmonella/microsome test. When tested with strain TA1538, the urine of nonsmoking chemical workers showed higher mutagenic activity than that of controls in the presence of in vitro metabolic activation, but no difference was found between controls and chemical workers who both smoked. Increased mutagenic activity was observed in the group of control smokers compared to control nonsmokers, but the same effect was not observed for chemical workers. When TA100 was used as the tester strain, the chemical workers, both smoking and nonsmoking, had significantly higher mutagenic activity than controls. The mutagenic activity fell to control levels in some workers' urine after 20 d leave. Although some perturbing effects of smoking habits were observed, the results seemed to indicate the usefulness of the Salmonella/microsome test for detection of mutagens in human urine. The results also suggest that people exposed to potentially carcinogenic chemicals may show high enough traces of those chemicals and/or their metabolites in their body fluids to be detected with current mutagenesis techniques.