401 research outputs found

    Deflection and Friction Performance of Waste-Wooden Block Pavements

    Get PDF
    The use of waste wood for road light pavements is essential for environmental and economic sustainability.The paper investigates the mechanical performance of pavements built with waste wood elements discarded from Sardinia manufacture (Italy). Without structural value, mainly Sardinian wood is used for combustion and heating due to the characteristics of dimensional irregularity, non-homogeneity, and the presence of defects. Even small urban and forest furniture comes from foreign markets. Landscape reasons, emissions reduction, and environmental integration with the local context could encourage its use if reliable techniques are available.The study first analyzed the structural response of a portion of pavementmade with waste wood bricks (pine and Eucalyptus). Subsequently, a Finite Element simulation of the pavement has been validated with the tests' results. The experimental pavement was created with Interlocked Block Pavement (IBP) technique, using brick elements 13 x 6 x 10 cm. The behavior of the pavement was analyzed in situ with dynamic deflection tests using the Falling Weight Deflectometer test (FWD). Further tests performed in the laboratory investigated the friction of the wood pavement surface. The simulation results show that the wooden pavement elements do not differ substantially from the classic concrete IBP and HMA cracked pavement. The mean deflections are greater than 19%, while the vertical stress on the foundation layer is equivalent. As with the classic concrete IBP, the results largely depend on the bearing capacity of the substrate and the degree of interlocking.Friction tests show good values with mean values of 53 divided by 64 BPN. The most significant values were observed in the elements eucalyptus. The direction of the wood fibers also influences the results: about 3 points in the case of pine and over 7 points in the case of Eucalyptus. The study shows how the use of wood for the pavement with elements is sustainable and practicable due to the minor and low-traffic roads while also guaranteeing permeability and low-cost maintenance

    Pyroclastic Stones as Building Materials in Medieval Romanesque Architecture of Sardinia (Italy): Chemical-Physical Features of Rocks and Associated Alterations

    Get PDF
    The paper discusses the chemical-physical-petrographic features and decay processes of San Nicola Church (11th−14th century) building materials, one of the most representative Medieval Churches in Sardinia, stylistically attributable to the Romanesque architecture. The monument was built up into two stages and shows a characteristic size uniformity of the ashlars. The masonry is mainly made up of rhyodacitic pyroclastites belonging to the Sardinian Eocene-Miocene magmatic phase (38–15 My). These volcanic rocks were widely used in Medieval architecture for the excellent workability, but its minero-petrographic features greatly favor the decay, due to the action of chemical-physical alteration processes. Although the alteration degree and macroscopic forms of decay vary from zone to zone in the monument, according to the different compositional features of the volcanic stones, weathering and exposure condition, the pyroclastic rocks are generally affected by greater alteration than other igneous lithotypes, due to their petrographic-volcanological characteristics (e.g., low-medium welding grade, medium-high porosity). The results concerning mineralogical and petrographic features, respectively, carried out by the application of X-Ray Powder Diffraction (XRPD), Optical Microscope (OM), and Scanning Electron Microscope (SEM) techniques, both on fresh building rocks and associated alterations, are here presented and discussed. Furthermore, the relationships between fresh pyroclastites and alteration processes affecting these rocks will be discussed

    Relationship between milk urea, blood plasma urea and body condition score in primiparous browsing goats with different milk yield level

    Get PDF
    Abstract. The aim of this study was to investigate the relationships among milk urea, blood plasma urea, milk yield and body condition score (BCS) in primiparous goats fed at pasture. Ninety goats of Sarda breed were used and, on the basis of their yield level, divided in three groups of 30 animals each, low (LY), intermediate (IY) and high milk yield (HY). Daily milk yield, milk protein content, milk urea, plasma total protein and albumin, plasma urea and BCS were measured at monthly intervals from 45 days in milking (45 DIM) to 165 DIM. Milk yield level affected protein concentration of milk and plasma, whereas albumin showed no variation. Plasma and milk urea showed a high correlation (P<0.001) despite of the yield level; plasma urea was always lower than milk urea. BCS decreased on 75 DIM and again after 135 DIM, and it was not affected by the milk yield level. Because milk urea and plasma urea were closely correlated and not influenced by the yield level, the study pointed out that measurement of milk urea could be utilized to evaluate urea metabolism also for browsing goats

    Microsatellite instability in ovarian neoplasms.

    Get PDF
    Microsatellite instability has been observed in a variety of sporadic malignancies, but its existence in sporadic ovarian cancer has been the subject of conflicting reports. We have performed a polymerase chain reaction-based microsatellite analysis of DNAs extracted from the neoplastic and non-neoplastic tissues of 41 ovarian cancer patients. Tumour-associated alterations were observed in seven (17%) of these cases. Clinicopathological correlations revealed that: (1) alterations among tumours classified as serous adenocarcinomas occurred with relatively low frequency (2/24 or 8%); (2) most of the tumours with microsatellite alterations (5/7 or 71%) were of less common histopathological types (epithelial subtypes such as endometrioid and mixed serous and mucinous, or non-epithelial types such as malignant mixed Müllerian or germ cell tumours); (3) tumour-associated alterations were observed in 3/4 (75%) of the patients with stage I tumours vs 4/37 (11%) of the patients with stage II, III and IV tumours (P = 0.01); (4) tumour-associated microsatellite instability was found to occur with similar frequencies among patients with and without clinical features suggestive of familial disease, including positive family history, early onset, or multiple primary tumours. In summary, we have observed microsatellite alterations in the neoplastic tissues of ovarian cancer patients with diverse genetic backgrounds and clinicopathological features. The pattern of alterations is consistent with the possibility that multiple mechanisms may be responsible for microsatellite instability in ovarian neoplasms

    Relationship between different livestock managements and stress response in dairy ewes

    Get PDF
    The gradual diffusion of intensive and semi-intensive production systems, especially in dairy sheep breeds, has led to the growing concern of consumers about the life conditions of farmed animals. Space allowance and structures of sheep houses are described as the main potential sources of discomfort for housed flocks, together with inappropriate milking procedures and human–animal interactions. The aim of the present study was to evaluate whether the structure relative to milking room could represent a stressor in Sarda dairy ewes. Animals were divided into two groups according to their farm of origin. Group A (n = 40) was from a farm whose milking room was an old warehouse with a waiting area limited and located outdoors and at a different level with respect to the milking room. The passageway of the entrance in the milking room was narrow and perpendicular to the milking positioning so the animal must bend 90° to enter in the room. Group B (n = 40) was from a farm whose milking room was wide and modern with a large waiting area located at the same level. From all animals blood samples were collected at T0 (2 h before milking procedure at 06:00), at T1 (immediately after the animals entered the milking room, about 08:00) and at T2 (after milking procedure). In addition plasma cortisol and glucose values were evaluated. Statistical analysis showed significant effect of milking room (P &lt; 0.001) and of sampling time (P &lt; 0.05) on cortisol and glucose levels. The results obtained in the present study suggest that, in addition to milking, the characteristics of the room where this procedure occurs represent stressful stimuli that could influence negatively the productivity and welfare of dairy ewes

    Relationship between different livestock managements and stress response in dairy ewes

    Get PDF
    Abstract. The gradual diffusion of intensive and semi-intensive production systems, especially in dairy sheep breeds, has led to the growing concern of consumers about the life conditions of farmed animals. Space allowance and structures of sheep houses are described as the main potential sources of discomfort for housed flocks, together with inappropriate milking procedures and human–animal interactions. The aim of the present study was to evaluate whether the structure relative to milking room could represent a stressor in Sarda dairy ewes. Animals were divided into two groups according to their farm of origin. Group A (n=40) was from a farm whose milking room was an old warehouse with a waiting area limited and located outdoors and at a different level with respect to the milking room. The passageway of the entrance in the milking room was narrow and perpendicular to the milking positioning so the animal must bend 90∘ to enter in the room. Group B (n=40) was from a farm whose milking room was wide and modern with a large waiting area located at the same level. From all animals blood samples were collected at T0 (2h before milking procedure at 06:00), at T1 (immediately after the animals entered the milking room, about 08:00) and at T2 (after milking procedure). In addition plasma cortisol and glucose values were evaluated. Statistical analysis showed significant effect of milking room (P&amp;lt;0.001) and of sampling time (P&amp;lt;0.05) on cortisol and glucose levels. The results obtained in the present study suggest that, in addition to milking, the characteristics of the room where this procedure occurs represent stressful stimuli that could influence negatively the productivity and welfare of dairy ewes.</p

    Effect of body condition score, treatment period and month of the previous lambing on the reproductive resumption of melatonin-treated sarda breed sheep during spring

    Get PDF
    Stakeholders place great emphasis upon rationalizing the management and rearing techniques which are utilized within sheep farms. The present study aimed to investigate factors which may improve the reproductive performance of melatonin-treated Sardinian sheep via a series of three trials. The first trial (n = 100) investigated the effect of melatonin treatment alongside body condition score (BCS), the second trial (n = 150) investigated the effect of treatment alongside the date of treatment (treatment period) and the third trial (n = 150) investigated the effect of treatment alongside the previous lambing of the ewes. The findings indicated that melatonin is an effective tool for anticipating and improving the reproductive activity of in Sarda breed sheep during the springtime. Furthermore, to obtain optional results, melatonin implantation should be conducted in April, in ewes that have a BCS of >2.5 and that have passed their third month of lactation. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Polymorphisms of the melatonin receptor 1A (MTNR1A) gene influence the age at first mating in autumn-born ram-lambs and sexual activity of adult rams in spring

    Get PDF
    The aim of this study was to determine whether polymorphisms of the melatonin receptor 1A (MTNR1A) gene influence the age at first mating in autumn-born ram-lambs and influence the out-of-season sexual activity of adult rams. In experiment 1, 24 Rasa Aragonesa ram-lambs born in September were genotyped for their RsaI and MnlI allelic variants of the MTNR1A gene, and the date of their first mounting with ejaculation after a period of semen collection training was documented. In experiment 2, the reproductive behavior, testicle size, and plasma testosterone concentrations of 18 adult rams (6 rams for each RsaI genotype) were recorded at the beginning (March) and end (May) of the seasonal anestrus. The number of days of training to achieve the first mating with ejaculation in T/T (C/C: 85.17 ± 12.08 C/T: 86.60 ± 18.87; T/T; 26.50 ± 24.50 d; P < 0.05), and G/G ram-lambs (G/G: 51.57 ± 14.99; A/G: 95.58 ± 10.95 d; P < 0.05) was significantly fewer than it was in the other genotypes. Likewise, for the RsaI genotype, 55% of the vulva-sniffing (P < 0.001), 48% of the approaches (P < 0.01), 48% of the mountings (P < 0.05) and 49% total activities (P < 0.001) were performed by T/T rams in March, and 50% of the sexual events in May (P < 0.001). For the Mnll variant, G/G rams performed a significantly (P < 0.001) larger proportion of the vulva-sniffing (41%), approaches (46%) and total activities (40%) in March, and 52% of the vulva-sniffing (P < 0.001), 43%, of the approaches (P < 0.001), 46% of the mountings (P < 0.05), and 47% of the total activities (P < 0.001) in May. Scrotal circumference, testicular volume, and plasma testosterone concentrations did not differ significantly among genotypes. Results confirmed that the polymorphisms of the MTNR1A gene sequence can influence reproductive performance in young and adult rams. Autumn-born ram-lambs that carried the T/T or G/G genotype had an advanced ability to reproduce, and T/T or G/G adult rams exhibited the most intense reproductive behavior. Genotyping might be a useful procedure for identifying the correct and rational use of rams in modern sheep farming

    End-User Development for eXtended Reality using a multimodal Intelligent Conversational Agent

    Get PDF
    In the past years, both the research community and commercial products have proposed various solutions aiming to support end-user developers (EUDevs), namely users without extensive programming skills, to build and customize XR experiences. However, current tools may not fully eliminate the potential for user errors or misunderstandings. In this paper, we present EUD4XR, a methodology consisting of an intelligent conversational agent to provide contextual help, to EUDevs, during the authoring process. The key characteristics of this agent are its multimodality, comprehending the user’s voice, gaze, and pointing, combined with the environment status. Moreover, the agent could also demonstrate concepts, suggest components, and help explain errors further to reduce misunderstandings for end-user developers of VR/XR
    • …
    corecore