A new method for the joint visualization of vascular structures and connective tissues: Corrosion casting and 1 N NaOH maceration

Corrosion casting combined with scanning electron microscopy (SEM) has been widely used to study the morphofunctional aspects of microcirculation in many organs. In this study, we present an optimization of the corrosion casting (CC) technique associating it with NaOH 1 N maceration method to obtain a clear visualization of the relationships existing between the microvascular architecture of an organ and its extracellular matrix. Briefly, experiments were performed macerating the tissue previously injected with a low viscosity acrylic resin in 1 N NaOH and then observing it at SEM. In this study, we present an application of this technique to better evaluate the extracellular components of the vascular wall in medium-sized and capillary vessels both in skin and in kidney. The results obtained yielded clear images of the three-dimensional layout of medium-sized and capillary vessels in comparison with the extracellular environment. Furthermore, detailed information was obtained on the three-dimensional layout of fibers constituting the walls of venules, arterioles, and capillaries. In addition, the tubular collagenic structures surrounding the excretory tubules of the kidney and the dermal glands of the skin were depicted and their relationships with their vascular supply described in detail. © 2006 Wiley-Liss, Inc

Histology and ultrastructure of a tissue-engineered collagen meniscus before and after implantation

The collagen meniscus implant (CMI) is a tissue-engineering technique designed to stimulate regeneration of meniscus-like tissue in cases of irreparable tears or previous meniscectomy. CMI morphology was investigated before and after implantation by light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). In a case series biopsy specimens were harvested from four patients who underwent a second arthroscopic look 6 months after placement of the CMI. CMI sections appeared composed of parallel connective laminae of 10-30 mu m, connected by smaller bundles (5-10 mu m). This connective network formed lacunae with diameters between 40 and 60 mu m. At greater magnification, the walls of the lacunae demonstrated tightly packed and randomly distributed collagen fibrils, with diameters ranging from 73 to 439 nm. In the biopsy specimens, the lacunae were filled with connective tissue that contained newly formed vessels and fibroblast-like cells, presenting an abundant rough endoplasmic reticulum and several mitochondria. In the extracellular matrix, the collagen fibrils showed uniform diameters (126 nm +/- 32 nm). The original structure of CMI was still recognizable, and no inflammatory cells were detected within the implant. The morphological findings of this case series demonstrate that CMI provides a three-dimensional scaffold suitable for colonization by precursor cells and vessels and leading to the formation of a fully functional tissue

Model-Based Control of Torque and Nitrogen Oxide Emissions in a Euro {VI} 3.0 L Diesel Engine through Rapid Prototyping

In the present paper, a model-based controller of engine torque and engine-out Nitrogen oxide (NOx) emissions, which was previously developed and tested by means of offline simulations, has been validated on a FPT F1C 3.0 L diesel engine by means of rapid prototyping. With reference to the previous version, a new NOx model has been implemented to improve robustness in terms of NOx prediction. The experimental tests have confirmed the basic functionality of the controller in transient conditions, over different load ramps at fixed engine speeds, over which the average RMSE (Root Mean Square Error) values for the control of NOx emissions were of the order of 55-90 ppm, while the average RMSE values for the control of brake mean effective pressure (BMEP) were of the order of 0.25-0.39 bar. However, the test results also highlighted the need for further improvements, especially concerning the effect of the engine thermal state on the NOx emissions in transient operation. Moreover, several aspects, such as the check of the computational time, the impact of the controller on other pollutant emissions, or on the long-term engine operations, will have to be evaluated in future studies in view of the controller implementation on the engine control unit

In Vitro Activity of Essential Oils Against Planktonic and Biofilm Cells of Extended-Spectrum β-Lactamase (ESBL)/Carbapenamase-Producing Gram-Negative Bacteria Involved in Human Nosocomial Infections

The aim of this study was to analyze the antibacterial activity of four essential oils (EOs), Melaleuca alternifolia, Eucalyptus globulus, Mentha piperita, and Thymus vulgaris, in preventing the development and spread of extended-spectrum -lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae, metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa and carbapenemase (KPC)-producing Klebsiella pneumoniae. A total of 60 strains were obtained from the stock collection from the Microbiology Laboratory of Hesperia Hospital, Modena, Italy. Twenty ESBLproducing E. coli, 5 K. pneumoniae, 13 KPC-producing K. pneumoniae, and 20 MBL-producing P. aeruginosa were cultured and reconfirmed as ESBL and carbapenamase producers. Polymerase chain reaction was used for the detection of genes responsible for antibiotic resistance (ESBL and KPC/MBL). Antibacterial activity of the EOs was determined using the agar disk diusion assay, and minimal inhibitory concentrations (MICs) were also evaluated. Lastly, adhesion capability and biofilm formation on polystyrene and glass surfaces were studied in 24 randomly selected strains. M. alternifolia and T. vulgaris EOs showed the best antibacterial activity against all tested strains and, as revealed by agar disk diusion assay, M. alternifolia was the most eective, even at low concentrations. This eect was also confirmed by MICs, with values ranging from 0.5 to 16 g/mL and from 1 to 16 g/mL, for M. alternifolia and T. vulgaris EOs, respectively. The EOs’ antibacterial activity compared to antibiotics confirmed M. alternifolia EO as the best antibacterial agent. T. vulgaris EO also showed a good antibacterial activity with MICs lower than both reference antibiotics. Lastly, a significant anti-biofilm activity was observed for the two EOs (*P < 0.05 and **P < 0.01 for M. alternifolia and T. vulgaris EOs, respectively). A good antibacterial and anti-biofilm activity of M. alternifolia and T. vulgaris EOs against all selected strains was observed, thus demonstrating a future possible use of these EOs to treat infections caused by ESBL/carbapenemase-producing strains, even in association with antibiotics

Asymmetric Labor Markets, Southern Wages, and the Location of Firms

This paper studies the behavior of firms towards weak labor rights in developing countries (South). A less than perfectly elastic labor supply in the South gives firms oligopsonistic power tempting them to strategically reduce output to cut wages. In an open economy, competitors operating in perfectly competitive labor markets meanwhile enjoy less aggressive competitors and raise output. Finally, competition effect reduces the ex-post output of a relocating firm. These effects reduce relative profitability of the South casting doubts on traditional beliefs that multinationals are attracted to regions with lower wages. Adopting a minimum wage unambiguously enhances Southern competitiveness and welfare

Accounting for Extreme Events in the Economic Assessment of Climate Change

Extreme events are one of the main channels through which climate and socio- economic systems interact. It is likely that climate change will modify their probability distributions and their consequences. The long-term growth models used in climate change assessments, however, cannot capture the effects of short-term shocks; they thus model extreme events in a very crude manner. To assess the importance of this limitation, a non-equilibrium dynamic model (NEDyM) is used to model the macroeconomic consequences of extreme events. Its conclusions are the following: (i) Dynamic processes multiply the extreme event direct costs by a factor 20; half of this increase comes from short-term processes; (ii) A possible modication of the extreme event distribution due to climate change can be responsible for significant GDP losses; (iii) The production losses caused by extreme events depend, with strong non-linearity, both on the changes in the extreme distribution and on the ability to fund the rehabilitation after each disaster. These conclusions illustrate that the economic assessment of climate change does not only depend on beliefs on climate change but also on beliefs on the economy. Moreover, they suggest that averaging short-term processes like extreme events over the five- or ten-year time step of a classical long-term growth model can lead to inaccurately low assessments of the climate change damages

Emissions Trading, CDM, JI, and More - The Climate Strategy of the EU

The objective of this paper is to assess the likely allocation effects of the current cli-mate protection strategy as it is laid out in the National Allocation Plans (NAPs) for the European Emissions Trading Scheme (ETS). The multi-regional, multi-sectoral CGE-model DART is used to simulate the effects of the current policies in the year 2012 when the Kyoto targets need to be met. Different scenarios are simulated in or-der to highlight the effects of the grandfathering of permits to energy-intensive instal-lations, the use of the project-based mechanisms (CDM and JI), and the restriction imposed by the supplementarity criterion

Urban Environmental Health and Sensitive Populations: How Much are the Italians Willing to Pay to Reduce Their Risks?

We use contingent valuation to elicit WTP for a reduction in the risk of dying for cardiovascular and respiratory causes, the most important causes of premature mortality associated with heat wave and air pollution, among the Italian public. The purpose of this study is three-fold. First, we obtain WTP and VSL figures that can be applied when estimating the benefits of heat advisories, other policies that reduce the mortality effects of extreme heat, and environmental policies that reduce the risk of dying for cardiovascular and respiratory causes. Second, our experimental study design allows us to examine the sensitivity of WTP to the size of the risk reduction. Third, we examine whether the WTP of populations that are especially sensitive to extreme heat and air pollution - such as the elderly, those in compromised health, and those living alone and/or physically impaired - is different from that of other individuals. We find that WTP, and hence the VSL, depends on the risk reduction, respondent age (via the baseline risk), and respondent health status. WTP increases with the size of the risk reduction, but is not strictly proportional to it. All else the same, older individuals are willing to pay less for a given risk reduction than younger individuals of comparable characteristics. Poor health, however, tends to raise WTP, so that the appropriate VSL of elderly individuals in poor health may be quite large. Our results support the notion that the VSL is individuated