1,074 research outputs found
Bianchi I effective dynamics in Quantum Reduced Loop Gravity
The effective quantum dynamics of Bianchi I spacetime is addressed within the
statistical regularization scheme in Quantum Reduced Loop Gravity. The case of
a minimally coupled massless scalar field is studied and compared with the
effective Loop Quantum Cosmology. The dynamics provided by the two
approaches match in the semiclassical limit but differ significantly after the
bounces. Analytical and numerical inspections show that energy density,
expansion scalar and shear are bounded also in Quantum Reduced Loop Gravity and
the classical singularity is resolved for generic initial conditions in all
spatial directions.Comment: 19 pages, 23 figures, 1 tabl
Decomposable medium conditions in four-dimensional representation
The well-known TE/TM decomposition of time-harmonic electromagnetic fields in
uniaxial anisotropic media is generalized in terms of four-dimensional
differential-form formalism by requiring that the field two-form satisfies an
orthogonality condition with respect to two given bivectors. Conditions for the
electromagnetic medium in which such a decomposition is possible are derived
and found to define three subclasses of media. It is shown that the previously
known classes of generalized Q-media and generalized P-media are particular
cases of the proposed decomposable media (DCM) associated to a quadratic
equation for the medium dyadic. As a novel solution, another class of special
decomposable media (SDCM) is defined by a linear dyadic equation. The paper
further discusses the properties of medium dyadics and plane-wave propagation
in all the identified cases of DCM and SDCM
Thermography : a non invasive method to investigate thermoregulation as welfare indicator in Naked Neck broiler chickens
Graphene-Polyaniline Biosensor for Carbamate Pesticide Determination in Fruit Samples
In this study, a simple, sensitive, and low cost electrochemical biosensor for the quantitative determination of carbamate pesticides has been constructed. A composite consisting of polyaniline (PANI) and graphene oxide was electrochemically synthesised on a platinum electrode. This sensor platform was then used in the biosensor construction by electrostatic attachment of the enzyme, horseradish peroxidase (HRP) onto the surface of the Pt/GO-PANI electrode. Voltammetric results concluded that HRP immobilised on the Pt/GO-PANI composite retained its bio-electrocatalytic activity towards the reduction of H2O2 and was not changed during its immobilisation. The Pt/GO-PANI/HRP biosensor was then applied to successfully detect standard carbamate pesticides in a 0.1 M phosphate buffer (PB; pH = 6.8) solution. Various performance and stability parameters were evaluated for the Pt/GO-PANI/HRP biosensor, which included the optimal enzyme loading, effect of pH and long-term stability of the biosensor on its amperometric behaviour. The Pt/GO-PANI/HRP biosensor was finally applied to the detection of three carbamate pesticides of carbaryl, carbofuran, and methomyl using the enzyme inhibition method. Carbaryl, carbofuran, and methomyl analyses were amperometrically determined using spiked real samples of orange, pear, and grapes, within a concentration range of 0.01–0.3 mg/L. These results indicated that the biosensor is sensitive enough to detect carbamate pesticides in real fruit matrices. The detection limit for carbaryl, carbofuran, and methomyl in real fruit samples by amperometric method was determined to be 0.136 mg/L, 0.145 mg/L, and 0.203 mg/L, respectively. The application of the Pt/GO-PANI/HRP biosensor has demonstrated that the biosensor is sensitive enough for amperometric detection and could be a useful tool in the screening of these pesticides at low concentrations
The use of thermography to assess the teeth temperature during resection by grinding in piglets
Damage distribution and seismological model of the November 24, 2004, Salo' (Northern Italy) earthquake
The West side of lake of Garda, in Northern Italy, was struck by a ML=5.2 earthquake on
November 24, 2004. The felt area is rather large (from Venice to Milan) and the damaged area
consists of 66 municipalities, with a number of homeless of about 2200 and estimated direct
damages of 215 millions of euros. Most of the damaged structures are old masonry buildings and
churches, while there were almost no damage to reinforced concrete structures. The observed
distribution of macroseismic intensity shows a strong azimuthal dependence, with high intensity
level in a 10x10 km2 area located SW to the epicentre and rather large dispersion of values
(ranging from V to VII-VIII) in the first 10 km epicentral distance.
Taking into account the vulnerability level of the damaged structures and the features of the
geological formations, we tried to explain the observed damage distribution in terms of finite fault
properties of the source, despite the moderate magnitude of the event.
Thus we hypothesised a fault geometry from seismotectonic considerations and we simulated the
event by a high frequency simulation technique (Deterministic Stochastic Method, DSM). The
synthetic ground motion parameters were converted into intensity values by empirical
relationships and local geological conditions were considered to explain some discrepancies
between simulated and observed intensities. It was possible to adequately reproduce both the
observed distribution of macroseismic intensity and the ground motion recorded by an
accelerometric station located at about 13 km epicentral distance
Play Picture Making Music Emotional Enrichment (PME) as Wellness Improvement in Captive Non-Human Primates
Diabetes influences cancer risk in patients with increased carotid atherosclerosis burden
Background and aims: Atherosclerosis and cancer share several risk factors suggesting that at least in part their pathogenesis is sustained by common mechanisms. To investigate this relation we followed a group of subjects with carotid atherosclerosis at baseline up for malignancy development.Methods and results: we carried out an observational study exploring cancer incidence (study endpoint) in subjects with known carotid atherosclerosis at baseline (n = 766) without previous cancer or carotid vascular procedures. During the follow-up (160 +/- 111 weeks) 24 cancer occurred, corresponding to an overall annual incidence rate of 0.11%. 10 diagnosis of cancer occurred in individuals with a carotid stenosis >50% (n = 90) whereas 14 in patients with a carotid stenosis <50% patients (n = 676) (p < 0.001). Respect to patients without cancer, diabetes was markedly more common in subjects with cancer diagnosis during the FU (37.3%vs75.0%, p < 0.001). After controlling for classic risk factors, carotid stenosis >50% (HR = 2.831, 95%CI = 1.034-5.714; p = 0.036) and diabetes (HR = 4.831, 95%CI = 1.506-15.501; p = 0.008) remained significantly associated with cancer diagnosis.Conclusions: to our knowledge this is the first study reporting a significant risk of cancer development in subjects with diabetes and high risk of cerebrovascular events, highlighting the need of a carefully clinical screening for cancer in diabetic patients with overt carotid atherosclerosis. (C) 2019 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved
The Use of Infrared Thermography fort he Monitoring of Udder Teat Stress Caused by Milking Machines
The aim of this study was to test infrared thermography (IRT) as a possible tool for scoring teat color changes after cluster removal; thus, indirectly, to classify the short-term stress of teats caused by milking machines. Thermographic images (n = 137) from three farms were collected and evaluated to calculate the average and maximum skin surface temperatures (SSTs) at the base, center, and tip of each teat (Tavg,B, Tavg,C, Tavg,T, Tmax,B, Tmax,C, and Tmax,T). Obtained results confirmed a significant relationship between the indicators Tavg, Tmax and the levels of teat color change (level one: pink-colored teat; level two: red-colored teat; level three: blue or purple-colored teat). Nevertheless, when a teat was considered to be stressed because its scoring fell in level 3 of the color-change scale used, sensitivity and specificity in the classification of the teat status ranged respectively between 45.6% and 54.3%, and 54.4% and 59.2%, for the indicators Tavg; and 56.5% and 60.9%, and 59.7% and 61.8%, for the indicators Tmax. When a teat was considered stressed because its scoring fell between the levels 2 and 3 of the scale adopted, sensitivity and specificity were between 49.0% and 55.8%, and 58.3% and 61.8%, for the indicators Tavg; and 55.8% and 59.9%, and 60.6% and 61.4%, for the indicators Tmax. As a consequence, the low values of sensitivity and specificity do not seem to justify the development of an ad hoc infrared device for the monitoring of udder teat stress. Nonetheless, this technology can be a viable solution for a preliminary evaluation of the mechanical stress of teats if a milking system would be equipped with an infrared sensor already in place for other purposes (e.g., the monitoring of udder health status)
A monitoring system for laying hens that uses a detection sensor based on infrared technology and image pattern recognition
In Italy, organic egg production farms use free-range housing systems with a big outdoor area and a flock of no more than 500 hens. With additional devices and/or farming procedures, the whole flock could be forced to stay in the outdoor area for a limited time of the day. As a consequence, ozone treatments of housing areas could be performed in order to reduce the levels of atmospheric ammonia and bacterial load without risks, due by its toxicity, both for hens and workers. However, an automatic monitoring system, and a sensor able to detect the presence of animals, would be necessary. For this purpose, a first sensor was developed but some limits, related to the time necessary to detect a hen, were observed. In this study, significant improvements, for this sensor, are proposed. They were reached by an image pattern recognition technique that was applied to thermografic images acquired from the housing system. An experimental group of seven laying hens was selected for the tests, carried out for three weeks. The first week was used to set-up the sensor. Different templates, to use for the pattern recognition, were studied and different floor temperature shifts were investigated. At the end of these evaluations, a template of elliptical shape, and sizes of 135 \uc3\u97 63 pixels, was chosen. Furthermore, a temperature shift of one degree was selected to calculate, for each image, a color background threshold to apply in the following field tests. Obtained results showed an improvement of the sensor detection accuracy that reached values of sensitivity and specificity of 95.1% and 98.7%. In addition, the range of time necessary to detect a hen, or classify a case, was reduced at two seconds. This result could allow the sensor to control a bigger area of the housing system. Thus, the resulting monitoring system could allow to perform the sanitary treatments without risks both for animals and humans
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