1,732 research outputs found
A multidisciplinary approach to evaluate the effectiveness of natural attenuation at a contaminated site
This study evaluates the natural attenuation of chlorinated hydrocarbons as remediation action in a contaminated site downtown the city of Parma (Italy). To achieve this goal, a combination of new investigation methods (bio-molecular analysis, compound specific isotope analysis, phytoscreening) has been proposed. The approach (named circular multi step) allows to: fully understand the phenomena that occur at the study site, design new investigation activities, and manage best practices. Consequently, each step of the approach improves the conceptual and numerical models with new knowledge. The activities carried out at the study site allowed to detect a contamination of perchloroethylene in a large part of the city of Parma and, of main importance, underneath a kindergarten. The results of the study did not show significant natural attenuation of chlorinated hydrocarbons and that the detected contamination could refer to the same unknown contaminant source. Furthermore, the innovative phytoscreening technique was applied to assess the presence of chlorinated hydrocarbons at the ground level. The plume spread was estimated through numerical modeling starting from potential contaminant sources. This study enhances the knowledge of groundwater flow and contamination in Parma and allows authorities to design new investigation/reclamation activities through management actions
High-speed and high-resolution 2D and 3D elemental imaging of corroded ancient glass by laser ablation-ICP-MS
In this work, laser ablation-inductively coupled plasma-mass spectrometry was used to investigate for the first time glass weathering mechanisms using high-resolution 2D and 3D elemental maps of altered layers of ancient glass. Roman archaeological glass shards, displaying several corrosion indicators, were studied using multiple raster-scanning ablation with high depth and lateral resolution. The concentration gradients of different elements were captured (in their variations from the surface to the bulk of pristine glass) by multiple ablations on degraded regions of interest to observe the dissolution of the glass network due to the hydration and leaching processes that occur during its alteration. The results indicated an enrichment of silicon and a depletion of alkaline/alkaline earth element concentration in the first few microns of depth under the surface area suggesting that a de-alkalinisation phenomenon occurs on the glass surface when ancient items have been buried under soil for extended timeframes. The layer-by-layer elemental distribution revealed also how the composition of the archaeological glass changes from the bulk to the surface, shedding light on the leaching behaviour of glass constituents during the alteration process
Factors affecting the patterns of total amount and proportions of leukocytes in Bovine milk
Differential leukocyte count (DSCC) in milk is considered important to improve knowledge of udder immune response. The investigations on milk DSCC were limited by the techniques available until recently, when a high-throughput tool to perform DSCC opened the way to explore these factors in rapid and economically sustainable ways. We hypothesized that DSCC alone does not fully describe the pattern of these cells, since the total amount is also influenced by milk yield and SCC. Therefore, this study was designed to describe DSCC and total amount of different leukocytes in milk during the course of lactation in cows differing in parity and in levels of SCC. This study considered 17,939 individual milk tests from 12 dairy herds in Lombardy Region, where DCC testing was applied in the period of February 2018\u2013December 2019 (23 months). The samples were divided into two subsets\u2014\u201chealthy\u201d (HS) with SCC 64200,000 cells/mL and \u201cinflamed\u201d (IS) with SCC >200,000 cells/mL. Cow in HS have a P + LT average between 5.0
7 108 and 3.0
7 109 cells. In IS cows, the values were 1.6
7 1010 and 2.5
7 1010. Therefore, the presence of a well-defined inflammatory process increased the overall amount of polymorphonuclear neutrophils (PMN) and lymphocytes (LYM) of 1 log, from 1
7 109 to 1
7 1010. The assessment of the total amount of PMN and LYM, to our knowledge, have never been reported in scientific literature; the values observed may be proposed as benchmarks for studies on udder immune response. When data were analyzed by days in milk (DIM),they showed that cows in first and second lactation have a significantly lower amount of PMN + LYM, when compared to cows in third and higher lactation. However, these differences are numerically not very large (7%), and suggest that, in healthy animals, the number of immune cells is kept as constant as possible. In IS, the analysis of trends based on DIM showed that both DSCC and P + LT have a significant negative trend. These data suggest that only in this group, the presence of high SCC as lactation proceeds is associated with a progressive increase in the number of macrophages. To the best of our knowledge, this is the first study describing the pattern of DSCC and the total amount of PMN + LYM in relation to parity, days in milk, and SCC, and it may be considered as the first contribution in the investigation on mammary gland immune response by the means of differential cell counts in milk
Crustal deformation and <i>AE</i> monitoring: annual variation and stress-soliton propagation
International audienceThe stress propagation through the crust can be effectively monitored by means of acoustic mission (AE) techniques (ultrasounds). The \textit{AE} intensity is indicative of the amount of stress that affects some lithospheric and/or crustal slab of some (ultimately unknown) scale size. In principle, such scale size can be different in different areas, as it depends on their respective tectonic setting, by which a variety of prime causes ought to be considered: every cause can eventually prevail over others. Two basic phenomena are here reported. If the crust behaves like a comparatively ideal elastic body, an annual variation is observed, which appears in-phase and correlated, when comparing AE records collected at the Italian site and on the Cephallonia Island. It seems being astronomically modulated, hence it should display a planetary scale. One likely explanation is in terms of the loading tide. Such interpretation can be confirmed by some additional modelling and analysis upon considering the motion of the Sun and of the Moon. A second observed effect refers to the case in which the crust feels the effect of the fatigue that reduces its elastic performance. The phenomenon can be described in terms of stress solitons that cross the area being monitored. They can be unambiguously recognised, and the possibility is therefore envisaged of eventually using them for measuring the propagation speed of stress through the crust over continental or planetary scales. The residuals, with respect to such regularly recognisable effects, of the recorded AE signals are to be investigated in a few subsequent analyses (in progress), as they appear to contain additional relevant physical information, still being much different from any simple random noise. A final recommendation ought therefore to be stressed, for setting up some array of at least a few AE recording stations to be simultaneously operated over some continental scale area and for a few years at least. Their potential applications still appear much promising and to be still focused in their complete, specific, operative and physical details and interpretation
Acoustic emission and released seismic energy
International audienceIntense crises of crustal stress appear to cross large regions, and to precede by several months the eventual occurrence of some strong earthquake within them. The phenomenon is not linear, and the stress control reflects some wide scale-size rather than local effects. The stress propagation through the crust can be effectively monitored by means of acoustic emission (AE) techniques (ultrasounds). The correlation is here investigated between crustal stress crises and the total release of seismic energy within some space domain around the AE recording site. Some clear inferences can be envisaged, although a significant diagnosis of the state of the crust within a given region ought to request arrays of simultaneously operated AE recorders. Some case histories are described dealing with the Italian peninsula and with the Cephallonia Island
Bilateral neglected posterior dislocation of the shoulder treated by reverse arthroplasty and contralateral osteochondral autograft. A case report
Bilateral posterior dislocation of the glenohumeral joint is an uncommon event, that can be missed at the initial presentation. We report the case of a 76-year old woman, who suffered a traumatic bilateral posterior dislocation, that was diagnosed three months later. She underwent surgical treatment on both shoulders in a single stage. Since the right shoulder showed a defect of the articular surface >50%, a reverse shoulder arthroplasty was performed on this side. The resected portion of the humeral head was retrieved and used as osteochondral graft to fill the reverse Hill-Sachs lesion of the left shoulder. At 18-month follow up, the patient was pain-free and had recovered excellent shoulder function on both sides: Constant score was 79 for the right shoulder and 88 for the left one. X-rays showed a grade 1 scapular notch of the right reverse prosthesis and good incorporation of the graft in the left shoulder, with no evidence of degenerative joint changes. Neglected posterior dislocations of the shoulder can be surgically treated by replacement or reconstruction. In case of bilateral injuries, the surgeon should carefully evaluate the pathoanatomy of both glenohumeral joints in order to choose and plan the most suitable procedure. If shoulder replacement is required on one side, the resected portion of the humeral head can be used as osteochondral autograft for a reconstruction procedure in the opposite side. The choice is influenced by several variables and decision-making might be challenging
Compositional changes by SIMS and XPS analyses on fresh and aged Roman-like glass
This study reports important analytical evidence of an unusual non-uniform element distribution in the superficial layers of glass matrices (from few nm up to 1 µm). The unforeseen observation was made on silica-soda-lime glass mock-ups before and after their artificial ageing, using secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) surface analysis techniques. The analyses showed a marked non-homogeneous element distribution at the glass surface. The results indicated a very low concentration of Na at the surface up to a depth of around 500 nm below the surface, where its concentration increases reaching a plateau. In addition, the profile distribution of H in the first 200 nm of the pristine glass surface indicated a diffusion of hydrogen from the surrounding environment to the glass network. Additional modifications during the glass ageing process related to external factors (such as temperature and humidity) were also identified in relation to sodium atoms, with atoms on the glass surface showing a different chemical state from those in the bulk. This study confirms that glass composition as well as glass alteration are non-homogeneous locally supporting the importance of studying glass surface as region of interaction with surrounding environment
Possible Approach to Esophageal Lung with Long Tracheobronchial Gap
Esophageal lung is a rare bronchopulmonary foregut malformation characterized by an anomalous origin of one of the main bronchi which arises from the esophagus. Less than 30 cases are reported in the literature. Therefore, there are no standardized guidelines for the treatment of this condition. We report a case of right esophageal lung diagnosed in a neonate. The patient was treated with thoracoscopic closure of the ectopic main bronchus in the neonatal period, followed by delayed pneumonectomy at 5 months of age. No prosthetic substitute was implanted in the ipsilateral hemithorax after pneumonectomy. The patient is now 4 years old and doing well, postpneumonectomy syndrome was never observed. Our strategy and the possible alternatives are discussed here
Crustal deformation and <i>AE</i> monitoring: annual variation and stress-soliton propagation
The stress propagation through the crust can be effectively monitored by means of acoustic mission (AE) techniques (ultrasounds). The extit{AE} intensity is indicative of the amount of stress that affects some lithospheric and/or crustal slab of some (ultimately unknown) scale size. In principle, such scale size can be different in different areas, as it depends on their respective tectonic setting, by which a variety of prime causes ought to be considered: every cause can eventually prevail over others. Two basic phenomena are here reported. If the crust behaves like a comparatively ideal elastic body, an annual variation is observed, which appears in-phase and correlated, when comparing AE records collected at the Italian site and on the Cephallonia Island. It seems being astronomically modulated, hence it should display a planetary scale. One likely explanation is in terms of the loading tide. Such interpretation can be confirmed by some additional modelling and analysis upon considering the motion of the Sun and of the Moon. A second observed effect refers to the case in which the crust feels the effect of the fatigue that reduces its elastic performance. The phenomenon can be described in terms of stress solitons that cross the area being monitored. They can be unambiguously recognised, and the possibility is therefore envisaged of eventually using them for measuring the propagation speed of stress through the crust over continental or planetary scales. The residuals, with respect to such regularly recognisable effects, of the recorded AE signals are to be investigated in a few subsequent analyses (in progress), as they appear to contain additional relevant physical information, still being much different from any simple random noise. A final recommendation ought therefore to be stressed, for setting up some array of at least a few AE recording stations to be simultaneously operated over some continental scale area and for a few years at least. Their potential applications still appear much promising and to be still focused in their complete, specific, operative and physical details and interpretation
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