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We complete the study of the model introduced in [11]. It is a two-color urn model with multiple drawing and random (non-balanced) time-dependent reinforcement matrix. The number of sampled balls at each time-step is random. We identify the exact rates at which the number of balls of each color grows to infinity and define two strongly consistent estimators for the limiting reinforcement averages. Then we prove a Central Limit Theorem, which allows to design a statistical test for such averages., arXiv admin note: text overlap with arXiv:2102.06287

The rich-get-richer rule reinforces actions that have been frequently chosen in the past. What happens to the evolution of individuals’ inclinations to choose an action when agents interact? Interaction tends to homogenize, while each individual dynamics tends to reinforce its own position. Interacting stochastic systems of reinforced processes have recently been considered in many papers, in which the asymptotic behavior is proven to exhibit almost sure synchronization. In this paper we consider models where, even if interaction among agents is present, absence of synchronization may happen because of the choice of an individual nonlinear reinforcement. We show how these systems can naturally be considered as models for coordination games or technological or opinion dynamics.

Objective No studies analyzing the role of dementia as a risk factor for mortality in patients affected by COVID-19. We assessed the prevalence, clinical presentation and outcomes of dementia among subjects hospitalized for COVID19 infection. Design Retrospective study. Setting COVID wards in Acute Hospital in Brescia province, Northern Italy. Participants We used data from 627 subjects admitted to Acute Medical wards with COVID 19 pneumonia. Measurements Clinical records of each patients admitted to the hospital with a diagnosis of COVID19 infection were retrospectively analyzed. Diagnosis of dementia, modalities of onset of the COVID-19 infection, symptoms of presentation at the hospital and outcomes were recorded. Results Dementia was diagnosed in 82 patients (13.1%). The mortality rate was 62.2% (51/82) among patients affected by dementia compared to 26.2% (143/545) in subjects without dementia (p

In 2019, the international student competition Urban Farm invited students from all over the world and different disciplines to join forces in order to reconvert three abandoned buildings into productive structures using soil-less technologies. One of the target locations was the abandoned school of Orzes village, in the Italian Alps, a mountain area that, along the last decades, has experienced lack of job opportunities and depopulation processes. Building on these social and economic obstacles, a landscape and collective re-generation project was designed in order to offer a new local economic identity, creating a network of indoor farms within abandoned buildings and targeting the production and processing of medicinal mushrooms and herbs. Such a network, called DolomiNet, defined the Orzes School as an administrative reference and productive model to be replicated and exported on the several abandoned buildings within the region. Furthermore, it allowed for the creation of a training and research centre within the former school, where future network members could be trained and investigation on new pharmaceutical products and lighting technologies could take place. The three pillars of innovation of the project stands on the following elements: 1) the forest biosystem: a sustainable productive model inspired by forest connections and based on CO2-O2 exchange among mushroom and plant growing chambers; 2) the green exoskeleton: a bioclimatic greenhouse applied on the building external shell with the double function of increasing productive volumes and provide thermal insulation to the building; 3) coofarming app: an immediate communication system between farmers and administrative centre, which concurrently guarantee a remote control of cultivation parameters.

Twenty-eight freshwater crayfish were collected from 8 streams and one small lake in the province of South Tyrol (North Italy) from autumn 1999 to spring 2001, in order to investigate the presence of branchiobdellidans. At 6 of the streams the white clawed crayfish (Austropotamobius pallipes italicus) was collected, while the noble crayfish (Astacus astacus), the exotic species: signal crayfish (Pacifastacus leniusculus) and spiny-cheek crayfish (Orconectes limosus) were respectively caught at the other 2 streams and at the lake. Except for O. limosus, branchiobdellidans were observed on all crayfish examined. On noble crayfish, specimens of Branchiobdella italica and Branchiobdella hexodonta were found on the same host. Branchiobdella italica was largely recovered from all white clawed crayfish. The specimens of signal crayfish were found to carry only Xironogiton victoriensis.

The methods of mortality analysis in Italian polluted sites (IPS) are described. The study concerned 44 IPSs; each one included one or more municipalities. Mortality at municipality level was studied in the period 1995-2002, using the following indicators: crude rate, standardized rate, standardized mortality ratio (SMR), and SMR adjusted for an ad hoc deprivation index. Regional populations were used as reference for indirect standardization. The deprivation index was constructed using the 2001 national census variables representing the following socioeconomic domains: education, unemployment, dwelling ownership, overcrowding. Mortality indicators were computed for 63 single or grouped causes. The results for all the 63 analysed causes of death are available for each IPS, and in this Chapter the results for each IPS for causes selected on the basis of a priori evidence of risk from local sources of environmental pollution are presented. The procedures and results of the evidence evaluation have been published in the 2010 Supplement of EpidemiologyPrevention devoted to SENTIERI.

In Italy, complete municipality-level data on specific-cause mortality have been available at central level since 1980; Italy's National Institute of Statistics (Istat) collects data from all municipalities using two sources: i) the Office of Vital Statistics; and ii) the Civil Status Office. The Office of Vital Statistics records data on events such as births, deaths and migration for the population with official residence in the municipality, with the aim of describing the resident population's structure and composition. The Civil Status Office records data on the demographic dynamics (not only marital status but also causes of death); the data refer to the population living in the municipality, independently of official residence. Changes in the status of a municipality (e.g., the creation of a new municipality or the unification of diverse municipalities) are often not recorded simultaneously by these two offices, so that the data do not correspond.

Continuous and intermittent administration of inhalational anesthetics has been successfully employed for treating pain during labor. We conjectured that intermittent sevoflurane administration would be effective for pain relief during labor without side effects to the mother or fetus. Fifty parturients breathed a mixture of 2–3% sevoflurane, oxygen and air before each uterine contraction began. The patients assessed the quality of analgesia by using a visual analogue scale (0–10) before the administration of sevoflurane and after each uterine contraction. All parturients but one were satisfied, demonstrating a mean visual analogue score before and after sevoflurane administration of 8.7±1.1 and 3.3±1.5, respectively. Apgar scores at 1 and 5min were 9 (range 5–9) and 10 (range 8–10), respectively. Our findings suggest that sevoflurane could be effective for the treatment of labor pain.

The uptake of 6-H3 thymidine in the optic tectum and the forebrain of the newt following injury to one of the two nervous areas, shows a marked proliferative response in the telencephalon in the presence of a lesion on the right optic tectum, and a poor response of the optic tectum after a lesion on the right telencephalic lobe. A similar proliferative response is also obtained when the specimens received only the cold shock. In both experimental conditions maximum uptake is obtained after 7 days. It is assumed that the matrix cells of the forebrain and the undifferentiated cells of the optic tectum respond differently to the regeneration factor released by the nervous tissue following a lesion or a cold shock.

In this study we examined the changes in cortical layers when Methylazoxymethanol-acetate (MAM) was injected on 13th, 15th and 17th day of gestation (MAM13, MAM15, MAM17). Prenatal MAM administration prevents neuron precursor proliferation; the subsequent cell number decrease is followed by an increase in size of surviving cells. When MAM was injected on 13th or 15th day of gestation the significant decrease in cell density, in II and III zone (MAM13) and in the upper layers (MAM15), was compensated by a proportional increase in cell size and synaptic density. When MAM was injected on 17th embryonal day it did not cause a significant change in the neuron density and soma size was not altered while the distribution of cell size among layers showed significant differences with respect to the controls. Our findings of some area and synaptic density show that the cell surface increase is proportional to the decrease in cell number and that in the surviving cells there is a rearrangement in synaptic connections that compensate for the cellular density decrease.

The telencephalic proliferative response has been studied in adult newts after lesion on the central nervous system. Both in the animals injured on the optic tectum and in those on the telencephalon a telencephalic proliferative response was observed, localized in the dorsal pallial areas and in the striatum. Quantitative analysis of the proliferative activity of the matrix cells present in the telencephalon showed a different response pattern. In the animals lesioned on the telencephalon the labelled cells are much more numerous in the injured hemisphere than in the healthy one and these cells persists at a high level even in the specimens fixed 90 days after the lesion. In this case no labelled cells are observed in the midbrain. The number of labelled cells in the animals lesioned on the optic tectum was identical in both telencephalic hemispheres; this number decreases from 15 to 30 days after the injury and at 90 days labelled cells are not observed. These data confirm the presence of a neuronotrophic factor released in the ependymal fluid and active on the telencephalic periventricular matrix cells but not on the undifferentiated cells of the grey layers of the optic tectum. It is also assumed that the proliferation of matrix cells of an injured area causes the formation of glial cells and neurons, such proliferation in an intact zone is oriented to differentiation of glial cells alone.

The localization and proliferative response of optic tectum matrix cells has been studied in adult newt following an experimental lesion on an optic lobe. The results show that 15 days after the lesion the cells in division, autoradiographically labelled, are located in the periventricular layer. Thirty days after the lesion the labelled cells are also found in the innermost grey layers; at 90 days the injured optic tectum regains the cytoarchitecture characteristic of this centre, with labelled cells, whether in the external or in the internal pyriform layers. In all the stages the labelled cells are also found in the periventricular layers of the controlateral optic tectum, in the dorsal pallium and in the striatum. The quantitative data exhibit the existence of a direct relationship between the number of proliferating cells in the injured optic lobe and the extent of the lesion. These data show the possibility of active cellular proliferation for the reconstruction of the lesioned nervous area and for restoration of the characteristic histological structure.

A method for the determination of rhenium on various supports is reported in which the separation is carried out without dissolution of the sample. The procedure may also be used when interfering species are present. It is shown that the elaboration of the data allows information to be obtained about the state of the rhenium and its interaction with the support.

The paper presents the results of a long study on the reliability of thin film conductors and cross-overs metallization for hybrid circuits. Three failure mechanisms are examined: electromigration, humidity corrosion and mechanical fatigue, which affect the complex hybrid circuits as a consequence of the current load, of the humidity and the electrical load and of the mechanical stresses induced by the encapsulant. For the humidity corrosion a new general quantitative formulation is proposed which relate temperature, polarization and R.H. with medium time to fail. The agreement between the proposed formulation and the results is verified both on unencapsulated and on encapsulated components and give an activation energy for NiCr-Au or TiPdAu materials of g f = 0.53 eV . Finally same cautelative design rules are proposed in order to have an acceptable reliability level from the design.

The vibrational, electronic (reflectance) and EPR spectra, as well as the magnetic properties of the garnet Ca 2 NaNi 2 V 3 O 12 and its solid solution Ca 2 NaMg 2-x Ni x V 3 O 12 were investigated. The results show that a fraction of the vanadium (V) ions can be replaced by vanadium (IV), depending on the thermal history of the samples. Besides, the existence of some kind of antiferromagnetic interactions as well as the presence of a Ni spin forbidden transition in the electronic spectrum can be inferred. Likewise, the vibrational study suggests that in the case of garnets, the Raman spectroscopy would be a very useful tool to study the substitutional processes in this type of material.

Plastic scintillator counters made of long slabs (200×20 cm 2 ) of different thickness have been tested with 120 cm long plexiglas light guides coupled to 58 AVP photomultipliers. The accuracies achieved in measuring the time of flight of 600 MeV/ c protons, which hit the counter at different distances from the photo-multiplier, range from 350 to 450 ps fwhh. The impact position of the particles is determined along the counter by the time difference, as measured from the two opposite ends, with an accuracy ranging from 4.5 to 5.5 cm fwhh.

After keeping specimens of Rana esculenta at 4 degrees C for 24 hrs., the Authors removed a plug of right optic tectum. Thirty days later they injected 6-H3 thymidine and on the 200th day after surgery sacrificed the animals. With this technique it is possible to show the high regenerative capacity of the optic tectum; in fact, it is possible to observe reconstruction of the typical cellular and fibre layers of the removed nervous area. The origin of the cellular elements which supported this regenerative process and the possible connection between these results and restoration of the hemotrophic embryonic conditions due to absence of the blood-brain barrier, consequent on the cold treatment, is discussed.

A polyclonal antiserum against androgens, i.e., testosterone, 5alpha-dihydrotestosterone and androstenedione, was tested to reveal target neurons of endogenous androgens in the hypothalamus of both intact and castrated male rats. Paraffin sections of hypothalamus and testis were immunostained by using Avidin-Biotin Complex method and 3-3' diaminobenzidine to visualize the immunoperoxidase complex. Conventional control experiments for method and antiserum specificity were performed. The antiserum proved to be specific for androgens, i.e., testosterone, 5alpha-dihydrotestosterone and androstenedione. The nuclear labeling observed in tissues stained by this procedure is consistent with the hypothesis that the labeled neurons contained DHT, which is the main testosterone metabolite active in the cell nucleus. The antiserum was effective in staining not only the hypothalamic neurons of intact males with normal serum levels of testosterone but also the hypothalamic neuron of castrated males with very low serum levels of testosterone. Evidence is presented indicating that the immunostaining technique represents a more specific and sensitive method to identify target neurons of endogenous androgens than autoradiography.

The ultrastructural distribution of alkaline phosphatase and Na+, K+-ATPase on the brain capillaries in Rana esculenta was investigated. Alkaline phosphatase activity appears both on the luminal and abluminal walls of the endothelial capillary cells; Na+, K+-ATPase is, instead, only present on the abluminal side. This different enzymatic distribution indicates that endothelial cells of the brain capillaries are polarized and the luminal and abluminal endothelial membranes are functionally different. The role of these two enzymatic activities is discussed in relation to the blood-brain barrier.

Titanium dioxide samples, containing iron (up to 8%), heated at 1273 K in air, have been investigated by X-ray diffraction, thermogravimetry, magnetic susceptibility measurements and chemical analysis. The results show that iron is incorporated as Fe(III) in a limited amount (up to 1.2–1.4 Fe atoms/100 Ti atoms) in the rutile structure. The iron in excess with respect to the solubility limit, reacts with TiO2 giving Fe2TiO5. The analysis of the magnetic susceptibility measurements, performed in a wide temperature range (100–800 K) shows that the incorporation of Fe(III) ions in the rutile structure is not random since pair or higher order clusters of iron ions are present with metal-metal interactions. When the samples are thermally treated in hydrogen, the incorporated iron ions are reduced by a two step process Fe(III) → Fe(II) → Fe(0). The first reaction takes place in solid solution, the second with segregation of the metal. The metallic particles interact with the oxide surface, giving a SMSI causing a reduction of the TiO2 matrix. The effect of the incorporated species on the TiO2 unit cell volume is also discussed.

The authors removed from Lacerta viridis specimens part of the dorsal hippocampus of one telencephalic hemisphere. The animals were sacrificed 110 and 260 days after the operation; 24 hours before the operation on the encephalon, each was dosed with 6--3H thymidine. An examination of the historadiographic slides showed a clear remedial process in the operated area which, 260 days after has renewed in thickness but was still minus its characteristic cellular layer. The area of the telencephalon affected by the remedial process was examined by the authors and they have put forward the hypothesis that in relation to the type of operation performed, said area is localized prevalently in the dorsal hippocampus of the caudal half of the telencephalic hemispherg. The authors have also shown that the remedial procress, though attenuated is still in progress. 260 days after the operation.

We have investigated the structure and the cholinesterase features of the brain capillaries in two adult Amphibians (Rana esculenta and Bufo bufo). We found that brain capillaries are un-fenestrated and the endothelial cell edges are joined by tight junctions. The brain capillaries in both species are characterized by high levels of AChE. This enzyme is only localized in the basal membrane, whereas we have found the reaction product neither in the endoplasmatic reticulum nor in the Golgi apparatus. On the contrary the brain capillaries are deprived of BuChE. Only in one experiment traces of reaction product were found. The significance of this datum and the non-nervous role of cholinesterase is discussed.

The authors removed a simple plug from the dorsal hippocampus, or from the dorsal hippocampus and part of the medial hippocampus in a telencephalic hemisphere in specimens of Lacerta viridis. The specimens were sacrificed some time after the operation after administration of 6-3 H thymidina. The examination of the emulsified slides showed that in these experimental condition no reparative process is observed, except for an impressive proliferation of cells and fibres which, from the meninx, bridges the cortical gap and, penetrating the telencephalic ventricle, attaches itself to the surrounding nerve tissue. The authors also described a limited cellular proliferation in the ependima of the telencephalic ventricles as a result of resection of the medial hippocampus; this observation is interpreted as a phenomenum connected to compensatory hypertrophy.

The permeability of cerebral vessels to exogenous peroxidase was studied in the newt. The reaction product was found only inside the cerebral or pial blood vessels. Electron microscope investigations revealed the presence of reaction product along the luminal area of vessels and in some parts of the intercellular spaces at the level of tight junctions joining endothelial cells. On the basis of the ultrastructural peroxidase localization, the presence of a brain-blood barrier in Triturus is discussed.

A histochemical light and electron microscopy study of acetylcholinesterase (AChE) was carried out on the regenerating opic tectum of adult newt. A plug of optic tectum was removed and 15 days later [6-H3] thymidine was injected. Ninety days after the lesion the brain was removed, treated for histochemical AChE-detection and autoradiographic analysis. This double treatment showed the capacity of these adult amphibians to regenerate the nervous tissue through the proliferation of undifferentiated elements and their subsequent differentiation into neurons as is shown by the presence of cells both labelled by [6-H3] thymidine and by the AChE-reaction product.

The permeability of the newt cerebral capillaries to lanthanum ion has been studied after perfusion with mannitol solutions of increasing molarity. In the control specimens lanthanum deposits were limited to the luminal side of the capillaries and tracer did not spread to the pericapillary spaces due to the tight junctions. Treatment with hypertonic solutions of mannitol (0.25M, 0.5M, 1M) caused opening of the blood brain barrier with a progressive increase in lanthanum between the endothelial cell edges, in the basal lamina and in the extracellular spaces of the nervous parenchyma in relation to the molarity of the mannitol solution. The spread of lanthanum is probably due to opening of the tight junctions between the endothelial cells, since pinocytotic vesicles labelled with tracer were not evident.

The Authors studied the antibacterial activity "in vitro" and "in vivo" of cefuroxime, cefamandole and cephalexin on the Gram-positive and Gram-negative bacterial strains of recent isolation. The results showed a greater antibacterial activity of cefuroxime than the other two cephalosporins, mainly on the Gram-negative beta-lactamase producing bacterial strains.