Evaluation of the impact of anthropogenic activities on arsenic, cadmium, chromium, mercury, lead, and polycyclic aromatic hydrocarbon levels in seafood from the Gulf of Naples, Italy.

The principal aim of this study was to monitor the occurrence of some metals and polycyclic aromatic hydrocarbons (PAHs) in fish and mussels from the Gulf of Naples. A comparison with previous researches of the same area was carried out, and the intakes of these compounds through the diet and their effect on the tolerable intake values (when available) were assessed. Cadmium (Cd), chromium (Cr), and lead (Pb) were detected by flameless atomic absorption spectroscopy (Cd, Cr, and Pb); arsenic (As) and mercury (Hg) were detected by applying the hydride method. PAHs were detected by high-performance liquid chromatography. Widespread contamination was found. Among the metals, Hg showed the highest maximum levels of 284.94 ng/g wet weight (ww) in fish and 480.00 ng/g ww in mussels. Chrysene, phenanthrene, fluoranthene, anthracene, and benzo[k]fluoranthene were the most common PAHs in fish, whereas benzo[a]anthracene, pyrene, phenanthrene, acenaphthylene, and acenaphthene were the most frequently occurring compounds in mussels. The concentrations of As, Cr, Hg, Pb, and PAHs in fish were found to decrease over a period of 30 years, whereas the Cd levels remained constant. The Hg, Pb, and PAH levels in mussels increased over the period 2010 to 2016. Finally, the average consumption of mussels led to the highest effect on the Tolerable Daily Intake of Hg, which was exceeded by 19%.

Lifelong Aerobic Exercise Reduces the Stress Response in Rats.

The aim of this study was to analyze the effects of lifelong aerobic exercise (AE) on the adaptive response of the stress system in rats. It is well known that hypothalamic-pituitary-adrenal axis (HPA) activity differs when triggered by voluntary or forced exercise models. Male Wistar rats belonging to exercise (E) or control (C) groups were subjected to chronic AE, and two cutoff points were established at 8 (middle age) and 18 months (old age). Behavioral, biochemical and histopathological studies were performed on the main components/targets of the stress system. AE increased adrenal sensitivity (AS), brain corticosterone (CORT) and corticotropin-releasing factor (CRF), but had no effect on the thymus, adrenal glands (AGs) weight or plasma CORT. In addition, AE exerted no effect on the sympathetic tone, but significantly reduced anxiety-related behavior and emotionality. Aging decreased AS and deregulated neuroendocrine feedback, leading to an anxiogenic state which was mitigated by AE. Histopathological and morphometric analysis of AGs showed no alterations in middle-aged rats but adrenal vacuolization in approximately 20% old rats. In conclusion, lifelong AE did not produce adverse effects related to a chronic stress state. On the contrary, while AE upregulated some components of the HPA axis, it generated an adaptive response to cumulative changes, possibly through different compensatory and/or super compensatory mechanisms, modulated by age. The long-term practice of AE had a strong positive impact on stress resilience so that it could be recommended as a complementary therapy in stress and depression disease.

Cities and regions in Britain through hierarchical percolation.

Urban systems present hierarchical structures at many different scales. These are observed as administrative regional delimitations which are the outcome of complex geographical, political and historical processes which leave almost indelible footprints on infrastructure such as the street network. In this work, we uncover a set of hierarchies in Britain at different scales using percolation theory on the street network and on its intersections which are the primary points of interaction and urban agglomeration. At the larger scales, the observed hierarchical structures can be interpreted as regional fractures of Britain, observed in various forms, from natural boundaries, such as National Parks, to regional divisions based on social class and wealth such as the well-known North-South divide. At smaller scales, cities are generated through recursive percolations on each of the emerging regional clusters. We examine the evolution of the morphology of the system as a whole, by measuring the fractal dimension of the clusters at each distance threshold in the percolation. We observe that this reaches a maximum plateau at a specific distance. The clusters defined at this distance threshold are in excellent correspondence with the boundaries of cities recovered from satellite images, and from previous methods using population density.

On the problem of boundaries and scaling for urban street networks.

Urban morphology has presented significant intellectual challenges to mathematicians and physicists ever since the eighteenth century, when Euler first explored the famous Königsberg bridges problem. Many important regularities and scaling laws have been observed in urban studies, including Zipf's law and Gibrat's law, rendering cities attractive systems for analysis within statistical physics. Nevertheless, a broad consensus on how cities and their boundaries are defined is still lacking. Applying an elementary clustering technique to the street intersection space, we show that growth curves for the maximum cluster size of the largest cities in the UK and in California collapse to a single curve, namely the logistic. Subsequently, by introducing the concept of the condensation threshold, we show that natural boundaries of cities can be well defined in a universal way. This allows us to study and discuss systematically some of the regularities that are present in cities. We show that some scaling laws present consistent behaviour in space and time, thus suggesting the presence of common principles at the basis of the evolution of urban systems.

Multifractal to monofractal evolution of the London street network.

We perform a multifractal analysis of the evolution of London's street network from 1786 to 2010. First, we show that a single fractal dimension, commonly associated with the morphological description of cities, does not suffice to capture the dynamics of the system. Instead, for a proper characterization of such a dynamics, the multifractal spectrum needs to be considered. Our analysis reveals that London evolves from an inhomogeneous fractal structure, which can be described in terms of a multifractal, to a homogeneous one, which converges to monofractality. We argue that London's multifractal to monofractal evolution might be a special outcome of the constraint imposed on its growth by a green belt. Through a series of simulations, we show that multifractal objects, constructed through diffusion limited aggregation, evolve toward monofractality if their growth is constrained by a nonpermeable boundary.

Exploring the evolution of London's street network in the information space: a dual approach.

We study the growth of London's street network in its dual representation, as the city has evolved over the past 224 years. The dual representation of a planar graph is a content-based network, where each node is a set of edges of the planar graph and represents a transportation unit in the so-called information space, i.e., the space where information is handled in order to navigate through the city. First, we discuss a novel hybrid technique to extract dual graphs from planar graphs, called the hierarchical intersection continuity negotiation principle. Then we show that the growth of the network can be analytically described by logistic laws and that the topological properties of the network are governed by robust log-normal distributions characterizing the network's connectivity and small-world properties that are consistent over time. Moreover, we find that the double-Pareto-like distributions for the connectivity emerge for major roads and can be modeled via a stochastic content-based network model using simple space-filling principles.

Gravity versus radiation models: on the importance of scale and heterogeneity in commuting flows.

We test the recently introduced radiation model against the gravity model for the system composed of England and Wales, both for commuting patterns and for public transportation flows. The analysis is performed both at macroscopic scales, i.e., at the national scale, and at microscopic scales, i.e., at the city level. It is shown that the thermodynamic limit assumption for the original radiation model significantly underestimates the commuting flows for large cities. We then generalize the radiation model, introducing the correct normalization factor for finite systems. We show that even if the gravity model has a better overall performance the parameter-free radiation model gives competitive results, especially for large scales.

Limited urban growth: London's street network dynamics since the 18th century.

We investigate the growth dynamics of Greater London defined by the administrative boundary of the Greater London Authority, based on the evolution of its street network during the last two centuries. This is done by employing a unique dataset, consisting of the planar graph representation of nine time slices of Greater London's road network spanning 224 years, from 1786 to 2010. Within this time-frame, we address the concept of the metropolitan area or city in physical terms, in that urban evolution reveals observable transitions in the distribution of relevant geometrical properties. Given that London has a hard boundary enforced by its long standing green belt, we show that its street network dynamics can be described as a fractal space-filling phenomena up to a capacitated limit, whence its growth can be predicted with a striking level of accuracy. This observation is confirmed by the analytical calculation of key topological properties of the planar graph, such as the topological growth of the network and its average connectivity. This study thus represents an example of a strong violation of Gibrat's law. In particular, we are able to show analytically how London evolves from a more loop-like structure, typical of planned cities, toward a more tree-like structure, typical of self-organized cities. These observations are relevant to the discourse on sustainable urban planning with respect to the control of urban sprawl in many large cities which have developed under the conditions of spatial constraints imposed by green belts and hard urban boundaries.

Aberrant right subclavian artery: incidence and correlation with other markers of Down syndrome in second-trimester fetuses.

OBJECTIVE: To assess the incidence of aberrant right subclavian artery (ARSA) and other strong markers of Down syndrome and their correlation in a large population of second-trimester Down syndrome fetuses assessed in a tertiary referral center. METHODS: Presence or absence of ARSA and other major ultrasound markers of Down syndrome was assessed in a population of 106 second-trimester Down syndrome fetuses referred to our unit for expert assessment and/or termination of pregnancy after karyotyping performed for positive first- or second-trimester screening or advanced maternal age or on maternal request. All cases in which the diagnosis of Down syndrome followed the ultrasound detection of major anomalies or soft markers were excluded from the study, as were all cases with a gestational age less than 14 + 0 weeks. We searched for the ARSA on the three vessels and trachea view using color or power Doppler. All fetuses underwent a thorough anatomic assessment and fetal echocardiography. The other Down syndrome markers assessed were: absent or hypoplastic nasal bone (NB-), defined as length < 5(th) centile; nuchal fold ≥ 5 mm; and mild pyelectasis (> 5 mm). In addition, the presence of major cardiac and extracardiac defects was recorded. A correlation analysis was then performed in order to investigate possible associations between markers and/or major anomalies. Postmortem or postnatal diagnostic confirmation was available in all cases. RESULTS: The mean (SD) gestational age at ultrasound assessment was 20.4 (4.1) weeks. The incidence of the various variables in the population of Down syndrome fetuses was: ARSA, 25%; NB-, 43%; nuchal fold ≥ 5 mm, 16%; pyelectasis, 17%; major heart defects, 41%; atrioventricular septal defect, 25%; and extracardiac anomaly, 24%. The presence of ARSA did not correlate with any of the other variables. The only positive correlations (P < 0.05) were between NB- and pyelectasis, and between cardiac and extracardiac defects. CONCLUSIONS: This represents the largest Down syndrome population assessed for ARSA. In this series, the incidence of ARSA was 25%, lower than previously reported in much smaller series. Its presence did not correlate with the presence of any other marker or major anomaly, including heart defects.

Role of four-dimensional ultrasound (spatiotemporal image correlation and sonography-based automated volume count) in prenatal assessment of atrial morphology in cardiosplenic syndromes.

OBJECTIVE: To assess the diagnostic role of four-dimensional ultrasound using spatiotemporal image correlation and Sonography-based Automated Volume Count (STIC-SonoAVC) in the identification of the morphology of the atrial appendages in cases with cardiosplenic syndrome. METHODS: This was a retrospective investigation of 22 fetuses with cardiosplenic syndromes seen at our institution over a 5-year period from January 2004. As control groups, 10 normal fetuses, five cases with a non-isomeric atrioventricular septal defect and five cases with other congenital heart diseases were also analyzed. For all fetuses, one or more cardiac volume datasets were available for offline analysis. Two-dimensional and four-dimensional echocardiography was carried out in all cases at the time of diagnosis using high quality three-dimensional equipment. Dedicated software was used to assess chamber morphology using the SonoAVC technique, which allows the creation of casts of hollow structures. Two different operators used the software. The first performed all steps up to positioning of the region of interest box. The second operator, who was blinded to clinical information, then rendered the cardiac chambers using the SonoAVC technique. This operator then used the rendered image to subjectively assess atrial morphology. RESULTS: Suitable rendered images of the cardiac chambers could be produced in 40/42 fetuses. In two cases of left atrial isomerism, advanced (34 weeks) and early (13 weeks) gestational age made it impossible to obtain adequate rendered images. In the remaining 40 cases (13 cases of left atrial isomerism, seven cases of right atrial isomerism, five cases of non-isomeric atrioventricular septal defect, five cases of other congenital heart diseases and 10 normal fetuses), atrial morphology was correctly identified by evaluation of the rendered images. CONCLUSION: Four-dimensional ultrasound with SonoAVC rendering allows correct identification of the morphology of atrial appendages in all cases of cardiosplenic syndromes in which an adequate cardiac volume dataset can be obtained for analysis.

Extracting directed information flow networks: an application to genetics and semantics.

We introduce a general method to infer the directional information flow between populations whose elements are described by n-dimensional vectors of symbolic attributes. The method is based on the Jensen-Shannon divergence and on the Shannon entropy and has a wide range of application. We show here the results of two applications: first we extract the network of genetic flow between meadows of the seagrass Poseidonia oceanica, where the meadow elements are specified by sets of microsatellite markers, and then we extract the semantic flow network from a set of Wikipedia pages, showing the semantic channels between different areas of knowledge.

[The surveillance of occupational risks. Problems and perspectives of the recent legislative framework after the national preliminary survey]. / I dati sanitari aggregati e di rischio dei lavoratori sottoposti a sorveglianza sanitaria. Risultati preliminari dello studio pilota nazionale sulle comunicazioni ex art. 40. D.lgs 81/2008.

BACKGROUND: Legislation in Italy concerning health, safety and prevention at the workplace recently established a new data communication standard OBJECTIVES: The findings are reported of a specific survey on 18 Local Health Units (ASL) over the entire Italian territory, aimed at identifying the critical points in data management and analyze the available information. METHODS: The occupational health physician for each company must collect and transmit information on the number of workers submitted to health surveillance protocols to the Local Health Unit. Information must be divided by risk factor and gender Local health Units then transmit the data to the Regions and finally to the Italian National Institute for Occupational Safety and Prevention (ISPESL). RESULTS: A sample of 22.977 companies was studied, providing information on about 410,009 workers undergoing health surveillance protocols. Carrying or moving heavy loads, exposure to noise, VDU and chemical substances were the most frequent risk factors. The difference between genders was significant in risk allocation, with exposures to VDU and biological agents prevalently among females. CONCLUSIONS: The information thus collected suffered from a lack of data organization and completeness in the sample under study, but nevertheless provides preliminary evidence of a map of occupational risks on a national basis, confirming the potential for the new law (D.Lgs 81/2008) to investigate health safety and prevention at the workplace.

Network properties of written human language.

We investigate the nature of written human language within the framework of complex network theory. In particular, we analyze the topology of Orwell's "1984" focusing on the local properties of the network, such as the properties of the nearest neighbors and the clustering coefficient. We find a composite power law behavior for both the average nearest neighbor's degree and average clustering coefficient as a function of the vertex degree. This implies the existence of different functional classes of vertices. Furthermore, we find that the second order vertex correlations are an essential component of the network architecture. To model our empirical results we extend a previously introduced model for language due to Dorogovtsev and Mendes. We propose an accelerated growing network model that contains three growth mechanisms: linear preferential attachment, local preferential attachment, and the random growth of a predetermined small finite subset of initial vertices. We find that with these elementary stochastic rules we are able to produce a network showing syntacticlike structures.

[Voluminous ectopic polycystic ovaries in Mayer-Rokitansky-Küster-Hauser syndrome]. / Voluminose ovaie policistiche ectopiche nella sindrome di Mayer-Rokitansky-Küster-Hauser.

We report the case of a 20-year-old woman with primary amenorrhea, normally developed sexual characteristics, infantile external genitals and absence of vaginal orifice. Blood chemistry studies showed elevated serum levels of gonadotropin, estrogens, testosterone, 17OH-progesterone, prolactin and TSH and low concentrations of FT(3) and FT(4). Cytogenetic karyotyping and in situ fluorescence hybridization revealed a 46,XX karyotype and the presence of Barr chromatin body. Laparoscopy disclosed absence of a vagina, apparently normal, enlarged tubes, multifolicular ectopic gonads and symmetric bilateral uterine buds. Diagnostic work-up included skeletal radiography, renal ultrasonography, intravenous pyelography, pelvic echography, pelvic phlebography and magnetic resonance imaging studies to demonstrate possible associations between the genitourinary and skeletal anomalies. Based on the clinical and laboratory findings, a diagnosis of Mayer-Rokitansky-Küster-Hauser syndrome was established, associated with the presence of enlarged ectopic polycystic ovaries in the abdominal cavity.

Cytokeratin 20-expressing M cells in tonsils take up particulate antigen. A site for the delivery of vaccines against oral pathogens?

Quantitative and qualitative control of oral bacterial flora is a major issue in oral pathology and in the prophylaxis against cavities. Recent findings suggest that it is possible to induce local immune responses delivering antigens on palatine tonsils. M cells play an important role in the start of the immune response. These cells are located in the epithelia overlaying mucosal lymphoid follicles and are responsible for the uptake of particulate antigens. The identification of reliable markers for M cell is therefore extremely important. Since it has been reported that tonsillar immunization leads to the secretion of high levels of specific salivary antibody, we undertook a study to identify a marker for tonsillar M cells in order to plan strategies of oral immunization against oral pathogens. We studied cytokeratin 20 expression in rabbit tonsils by immunofluorescence and confocal microscopy. Cytokeratin 20 immunoreactive cells were observed in all samples examined. These cells were identified as M cells as they co-expressed vimentin, a well-known marker of rabbit M cells, and they actively uptook particulate material. It is therefore possible to hypothesize the use of tonsil M cells as a possible site for antigen delivery of particle-based vaccines against oral pathogens.

Dihydronicotinamide adenine dinucleotide diaphorase in the central nervous system of the crested newt.

By using a histochemical procedure, the distribution of neurons containing dihydronicotinamide adenine dinucleotide diaphorase (NADPHd) was examined in the brain, retina and olfactory epithelium of the urodele amphibian Triturus carnifex. Positive nerve fibers and terminals were observed throughout the brain and cell bodies were seen within the telencephalon, optic tectum, brain stem, cerebellum and spinal cord. In the retina, NADPHd labeling was localized in the outer segment of photoreceptors and in some amacrine cells as well as in the outer and inner plexiform layers. In the olfactory epithelium, NADPHd labeling was found in the olfactory neurons. By comparing NADPHd distribution with nitric oxide synthase (NOS) immunoreactivity (using a polyclonal antiserum raised against mouse cerebellar NOS) it was found that NADPHd labeling and NOS immunoreaction patterns generally matched. The organization of NADPHd and NOS containing neurons in the central nervous system of the crested newt, which is simpler than in other vertebrates investigated, shows some peculiarities, such as the occurrence of NADPHD in the pinealocytes of the epiphysis, nucleus rubber of the brain stem and eminentia cerebellaris ventralis of the cerebellum.