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Valutazione degli isoenzimi della fosfatasi alcalina nel cane tramite precipitazione con lectina di germe di grano ed inibizione con tetramisolo: risultati preliminari
No full textRIASSUNTO Nel siero di cane è possibile valutare l’attività di 3 isoenzimi della fosfatasi alcalina (ALP): l’isoenzima epatico (LALP), l’isoenzima osseo (BALP) e l’isoenzima glicocorticoide- indotto (CALP) che si trova solo in questa specie. Poiché nel cane la misurazione dell’ALP totale (TALP) nel siero risulta un test poco specifico, lo studio delle forme isoenzimatiche può aiutare nell’interpretazione di un suo incremento, in particolare in corso di iperadrenocorticismo, patologie neoplastiche e croniche in genere. La quantificazione degli isoenzimi è stata eseguita su 19 campioni di plasma di cani con livelli di TALP superiori a 200 U/L (valori di riferimento 50-130 U/L) applicando la metodica che combina la precipitazione selettiva con WGL (Wheat Germ Lectin) all’inibizione chimica con tetramisolo 4,2 mM. Nel 100% dei cani con morbo di Cushing la CALP rappresentava l’isoenzima predominante, mostrando quindi una buona accuratezza (89%) e specificità (85%) diagnostiche, ed un ottima sensibilità (100%). Tra i valori di TALP e CALP non è stata evidenziata però alcuna correlazione significativa (p<0,05), così come non correlati significativamente risultano gli incrementi di LALP e CALP, riscontrati rispettivamente nell’88,9% e 11,1% dei pazienti con patologia cronica. Tale dato può essere messo in relazione ad una possibile induzione degli isoenzimi in diversi tessuti o l’induzione di enzimi a loro volta responsabili del rilascio degli isoenzimi dell’ALP dalle membrane cellulari. Nel gruppo dei pazienti neoplastici è stata evidenziata una correlazione statisticamente significativa (p<0,05) fra il valori di TALP e di LALP, che risulta l’enzima prevalente nell’80% dei soggetti. Tale risultato suggerisce la possibilità di una patologia epatica subclinica nel paziente oncologico, o un aumento del cortisolo endogeno, che induce inizialmente un incremento della LALP e successivamente della CALP. La valutazione degli isoenzimi dell’ALP attraverso questa metodica, che risulta economica e piuttosto rapida, può quindi essere utile nello screening dell’iperadrenocorticismo del cane, nonché per lo studio dei meccanismi eziopatogenetici alla base dell’iperfosfatasemia in corso di patologie croniche e neoplastiche. SUMMARY In canine serum three isoenzymes are identified: liver ALP (LALP), bone ALP (BALP), corticosteroid-induced ALP (CALP) which is present only in this species. As total ALP activity (TALP) in serum has low specificity in dog, the evaluation of isoenzymes can be useful to interpretation of hyperphosphatasemia. Nineteen canine plasma samples with TALP activity over 200 U/L (reference range for healthy dogs: 50-130 U/L) were tested and isoenzymes were determinate with an assay combining wheat germ lectin (WGL) precipitation and chemical inhibition with tetramisole 4.2 mM. The CALP is the prevalent isoenzyme in 100% of dogs with hyperadrenocorticism, showing a good accuracy (89%) and specifity (85%), and a very good sensitivity (100%). Serum total AP activity was not significantly and positively correlated (p<0.05) with CALP in patients with hyperadrenocorticism, and with LALP (88.9% of cases) and CALP (11.1% of cases) in dogs with chronic illness. This finding suggests possible induction of isoenzymes in several tissues or induction of enzymes responsible for release of ALP isoenzymes from cellular membranes. In neoplastic group, a significant correlation (p<0.05) was noted within TALP and LALP values, prevalent isoenzymes in 80% of dogs. This finding can result from subclinical liver injury in neoplastic dog, or an increment of cortisol, that induce an early LALP increase and subsequently an increase of CALP. In dogs, ALP isoenzymes determination, with this method, cheap and somewhat rapid, can result as a useful screening test for Cushing syndrome, and for study of ethiopathogenetic mechanisms of hyperphosphatasemia during chronic and neoplastic illness
Der Städtebau nach seinen künstlerichen Grundsätzen: la piazza come fondamento dell’urbanistica
Get PDFL'articolo presenta il libro di Camillo Sitte "Der Städtebau nach seinen künstlerischen Grundsätzen", pubblicato nel 1889 a Vienna, evidenziando l'importanza di tali riflessioni nella storia dell'urbanistica. Si pone l'accento in particolare sul tema della piazza
Chiral transition and deconfinement in N_f = 2 QCD
No full textThe transition is studied by means of a disorder parameter detecting
condensation of magnetic monopoles in the vacuum. The deconfining transition is
found to coincide with the chiral transition and the susceptibility \rho,
related to the disorder parameter, is consistent with a first order phase
transition
Laser acceleration of ion bunches at the front surface of overdense plasmas
No full textSUMMARY The acceleration of ions in the interaction of high intensity laser pulses
with overdense plasmas is investigated with particle-in-cell simulations. For
circular polarization of the laser pulses, high-density ion bunches moving into
the plasma are generated at the laser-plasma interaction surface. A simple
analytical model accounts for the numerical observations and provides scaling
laws for the ion bunch energy and generation time as a function of pulse
intensity and plasma density
Resonant nonlinear quantum transport for a periodically kicked Bose condensate
No full textSUMMARY Our realistic numerical results show that the fundamental and higher-order
quantum resonances of the delta-kicked rotor are observable in state-of-the-art
experiments with a Bose condensate in a shallow harmonic trap, kicked by a
spatially periodic optical lattice. For stronger confinement,
interaction-induced destruction of the resonant motion of the kicked harmonic
oscillator is predicted
The scaling equation of state of the three-dimensional O(N) universality class: N >= 4
No full textWe determine the critical equation of state of the three-dimensional O(N)
universality class, for N=4, 5, 6, 32, 64. The N=4 is relevant for the chiral
phase transition in QCD with two flavors, the N=5 model is relevant for the
SO(5) theory of high-T_c superconductivity, while the N=6 model is relevant for
the chiral phase transition in two-color QCD with two flavors. We first
consider the small-field expansion of the effective potential (Helmholtz free
energy). Then, we apply a systematic approximation scheme based on polynomial
parametric representations that are valid in the whole critical regime, satisfy
the correct analytic properties (Griffiths' analyticity), take into account the
Goldstone singularities at the coexistence curve, and match the small-field
expansion of the effective potential. From the approximate representations of
the equation of state, we obtain estimates of universal amplitude ratios. We
also compare our approximate solutions with those obtained in the large-N
expansion, up to order 1/N, finding good agreement for N \gtrsim 32
Multicritical behavior in frustrated spin systems with noncollinear order
No full textWe investigate the phase diagram and, in particular, the nature of the the
multicritical point in three-dimensional frustrated -component spin models
with noncollinear order in the presence of an external field, for instance
easy-axis stacked triangular antiferromagnets in the presence of a magnetic
field along the easy axis. For this purpose we study the renormalization-group
flow in a Landau-Ginzburg-Wilson \phi^4 theory with symmetry O(2)x[Z_2 +O(N-1)]
that is expected to describe the multicritical behavior. We compute its MS
\beta functions to five loops. For N\ge 4, their analysis does not support the
hypothesis of an effective enlargement of the symmetry at the multicritical
point, from O(2) x [Z_2+O(N-1)] to O(2)xO(N). For the physically interesting
case N=3, the analysis does not allow us to exclude the corresponding symmetry
enlargement controlled by the O(2)xO(3) fixed point. Moreover, it does not
provide evidence for any other stable fixed point. Thus, on the basis of our
field-theoretical results, the transition at the multicritical point is
expected to be either continuous and controlled by the O(2)xO(3) fixed point or
to be of first order
Modeling Web Applications by the Multiple Levels of Integrity Policy
No full textWe propose a formal method to validate the reliability of a web application, by modeling interactions among its constituent objects. Modeling exploits the recent "Multiple Levels of Integrity" mechanism which allows objects with dynamically changing reliability to cooperate within the application. The novelty of the method is the ability to describe systems where objects can modify their own integrity level, and react to such changes in other objects. The model is formalized with a process algebra, properties are expressed using the ACTL temporal logic, and can be verified by means of a model checker. Any instance of the above model inherits both the established properties and the proof techniques. To substantiate our proposal we consider several case-studies of web applications, showing how to express specific useful properties, and their validation schemata. Examples range from on-line travel agencies, inverted Turing test to detect malicious web-bots, to content cross-validation in peer to peer systems
Testability of SPP Three-Level Logic Networks in Static Fault Models
No full textRecently introduced, three-level logic Sum of Pseudoproducts (SPP) forms allow the representation of Boolean functions with much shorter expressions than standard two-level Sum of Products (SOP) forms, or other three-level logic forms. In this paper the testability of circuits derived from SPPs is analyzed. We study testability under static Fault Models (FMs),i.e., the Stuck-At Fault Model (SAFM) and the Cellular Fault Model(CFM). For SPP networks several minimal forms can be considered. While full testability can be proved in the SAFM for some forms, SPP networks in the CFM are shown to contain redundancies. Finally, we propose a method for transforming non-testable networks into testable ones. Experimental results are given to demonstrate the efficiency of the approach
Analisi della variabilità genetica in una popolazione ovina di razza massese e studio di associazione con parametri di qualità del latte
No full textRIASSUNTO Il presente lavoro ha come obiettivo la ricerca di associazioni tra marcatori microsatellite e la composizione chimica del latte. È stato condotto uno studio su 68 pecore di razza Massese provenienti da un allevamento toscano. A partire da latte fresco, sono stati valutati: composizione chimica standard, contenuto in caseina e frazioni caseiniche, proteine seriche, pH e parametri reologici. I capi sono stati sottoposti a genotipizzazione impiegando 17 marcatori microsatellite; sono, quindi, stati calcolati i valori di similarità genetica tra individui ed alcuni parametri genetici classici. Il numero medio di alleli per locus è risultato pari a 7,18 e l’eterozigosità osservata presentava variazioni tra 0,403 e 0,867 (media 0,677). La similarità genetica tra individui era 0,460. Cinque marcatori (BM8124, CSN3, BM1258, BMS468 e TGLA387) hanno mostrato una deviazione significativa dalle proporzioni di Hardy- Weinberg. Lo studio ha messo in evidenza alcuni microsatelliti con alleli significativamente associati a caratteri di composizione del latte (P<0,01). In particolare, la significatività più alta (P<0,001) è stata osservata per l’associazione dell’allele 2 del marcatore OIFNG con la a-lattoalbumina, dell’allele 10 del marcatore BL4 con il livello di immunoglobuline, dell’allele 2 del marcatore BMC1009 con il contenuto di grasso e dell’allele 9 del marcatore ILSTS42 con il parametro a30. Sono necessari ulteriori approfondimenti al fine di convalidare i risultati preliminari ottenuti nel presente lavoro e si rende necessaria l’estensione dello studio ad un numero maggiore di soggetti e la tipizzazione di un numero maggiore di loci, principalmente sui cromosomi 3 e 20 dove mappano i marcatori risultati più interessanti nella presente analisi. SUMMARY Current research aims to establish statistical associations between DNA microsatellites and milk chemical composition. Atrial was carried out on 68 Massese ewes reared in a farm of the Tuscany. The following parameters were evaluated on fresh milk: standard chemical composition, casein and its fractions, whey proteins, pH and rheological parameters. Animals were genotyped at 17 microsatellite loci. Genetic similarities among individuals and classical genetic parameters were evaluated. For each locus, average values of considered parameters were calculated in all the subjects carrying a given allele; these were compared statistically with the average values of subjects not carrying the allele, and the significance of the difference was estimated. The average number of alleles per locus resulted 7.18 and the observed heterozygosity ranged from 0.403 to 0.867 (0.677 medium value). The genetic similarity among individuals was 0.460. Five markers pointed out a significant deviation from the Hardy-Weinberg proportions (BM8124, CSN3, BM1258, BMS468 and TGLA387). The study revealed several microsatellites with alleles significantly linked to milk composition traits (P<0.01). In particular the highest significance (P<0.001) has been found for the allele 2 of OIFNG marker with a-lactoalbumin, for the allele 10 of the BL4 marker with immunoglobulins, for the allele 2 of BMC1009 with fat, and for allele 9 of ILSTS42 with a30. Further analyses are needed to validate these preliminary results, in particular increasing the number of subjects and of typed loci above all on the chromosomes 3 and 20 where the more interesting markers map