104,424 research outputs found
Detection of digital and interdigital dermatitis in holstein friesian dairy cows by means of infrared thermography
No full textDiseases of the bovine foot are a serious threat to dairy cows welfare and productivity. Commonly divided in infectious and non-infectious depending on their aetiology, infectious lesions include digital dermatitis, interdigital dermatitis, heel horn erosion, and foot rot, whereas the most common non-infectious lesions are sole ulcer, toe ulcer, sole haemorrhage, and white line dis-ease. Infrared thermography (IRT) has been adopted in livestock studies for different analyses such as metabolic responses to thermal stress and the diagnosis of inflammatory processes. The aim of this study was to evaluate the potential usefulness of infrared thermography as a non-invasive tool to rapidly screen digital and interdigital dermatitis (DD and ID) in dairy cows. Forty-eight healthy cows and forty-eight cows affected by DD and ID on central and interdigital regions of the hind feet were enrolled. Feet were cleansed to reduce biases and artifacts and left to dry for five minutes to restore normal blood flow. Thermography images of the hind feet were then collected using a digital infrared camera. Foot temperature was measured in four regions: central area of the hind foot (R1), interdigital area of the hind foot (R2), lateral (R3) and medial (R4) claw in the hind foot. Higher temperature values were found in the central (R1) and interdigital area (R2) compared to lateral (R3) and medial (R4) areas in both healthy and diseased cows (P<0.001). Moreover, cows affected by DD and ID showed higher foot temperature values compared to healthy cows in the R1 and R2 regions (P<0.001). Results from the present study show that IRT could be a useful diagnostic tool for the detection of DD and ID in dairy cows. The obtained results suggest that IRT could contribute in defining the localization of areas of increased inflammation and could be useful for veterinary podologists, permitting to act directly on the lesion detected by thermography rather than on the whole foot
Catene di appalti e modelli di organizzazione e gestione della sicurezza sul lavoro: contenuti e limiti della traslazione dello statuto della responsabilità dalla persona fisica all’ente collettivo
No full textThe article aims at addressing the issue of the shift of the liability models in procurement chains from the natural person to the corporation. Drawing from the complexity inherent in the fragmentation of production activities and the coexistence of many corporations with employer status, the article proposes a modulation of the principal’s key duties based on the summa divisio between “internalized” and “outsourced” procurements, giving importance to the compliance programs for risk organization and management which, in a complex matter such as this, can make it possible to shift the center of gravity from the event to prevention and safety organization of the workplace in line with the principles of the corporate organizational fault and the due limitations of the corporate supervision duties to the extent of labour criminal law.Il saggio affronta il tema della traslazione dalla persona fisica all’ente dello statuto della responsabilità nelle catene di appalti. Traendo le mosse dalla considerazione della complessità insita nella frammentazione della produzione e nella coesistenza di diversi enti con qualifica datoriale, si propone una modulazione dei doveri caratteristici della società committente in base alla summa divisio tra appalti “internalizzati” ed “esternalizzati” attribuendo rilievo centrale al ruolo dei modelli di organizzazione e gestione del rischio i quali, in una materia complessa come questa, possono consentire di spostare il baricentro dalla realizzazione dell’evento alla prevenzione e all’organizzazione della sicurezza nel rispetto del principio di colpevolezza organizzativa e della conseguente limitazione dei doveri di vigilanza dell’ente agli effetti del diritto penale del lavoro
Tuning ultrafast electron injection dynamics at organic-graphene/metal interfaces
No full textThe properties of novel and prospective 2D materials are dramatically influenced by the interaction with a substrate. For example, the electronic hybridization of silicene states on Ag(111) or graphene ones on Ni(111) disrupts the Dirac fermions of the freestanding layers. This calls for efficient approaches to tune the interaction strength at the interface. Here we focus on the case of graphene functionalized by organic molecules and grown on Ni(111) and on the interfacial charge transfer dynamics. This is investigated by X-ray resonant photoemission spectroscopy, that is able to measure electron transfer rates occurring within few femtoseconds, and by a theoretical framework based on density-functional theory [1,2].
We use 4,4’-bipyridine as the prototypical molecule for these explorations as the energy level alignment of core-excited molecular orbitals allows ultrafast injection (τ=4fs) of electrons from the substrate to the molecule adsorbed on epitaxial graphene/Ni(111), which is characterized by a strong hybridization between C and metal states. We demonstrate that this interface can be decoupled by the addition of a second layer of graphene, where the one in contact with the metal acts as a buffer layer and the one in contact with the molecule is less hybridized with Ni underneath. As a result, the ultrafast injection of electrons from the substrate to the molecule is ∼4 times slower on weakly coupled bilayer graphene than on epitaxial graphene. Through our experiments and calculations, we can attribute this to a difference in the density of states close to the Fermi level between graphene and bilayer graphene. We therefore show how graphene coupling with the substrate influences charge transfer dynamics between organic molecules and graphene interfaces.
[1] G. Fratesi, C. Motta, M. I. Trioni, G. P. Brivio, and D. Sánchez-Portal, J. Phys. Chem. C 118, 8775 (2014)
[2] D. Cvetko, G. Fratesi, G. Kladnik, A. Cossaro, G.P. Brivio, L. Venkataraman, and A. Morgante, Phys. Chem. Chem. Phys. 18, 22140 (2016)
[3] A. Ravikumar, G. Kladnik, M. Müller, A. Cossaro, G. Bavdek, L. Patera, D. Sánchez-Portal, L. Venkataraman, A. Morgante, G. P. Brivio, D. Cvetko, and G. Fratesi, Nanoscale 10, 8014 (2018)
Individuazione di standard di prevenzione del rischio e regole di compliance nel giudizio su d. lgs. 231/2001
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