950 research outputs found

    Measuring Investment Distortions when Risk-Averse Managers Decide Whether to Undertake Risky Projects

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    This paper examines distortions in corporate investment decisions when a new project changes firm risk. It presents a dynamic model in which a self-interested, risk-averse manager makes investment decisions at a levered firm. The model, calibrated using data from public firms, is used to estimate the magnitude of distortions in investment decisions. Despite potential wealth transfers from debtholders, managers compensated with equity prefer safe projects to risky ones. Important factors in this decision are the expected changes in the values of future tax shields and bankruptcy costs when firm risk changes. We also evaluate the extent to which this effect varies with firm leverage, managerial risk aversion, managerial non-firm wealth, project size, debt duration, and the structure of management compensation packages.

    Sequential biological and photocatalysis based treatments for shipboard slop purification: A pilot plant investigation

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    This study investigated the treatment of a shipboard slop containing commercial gasoline in a pilot plant scale consisting of a membrane biological reactor (MBR) and photocatalytic reactor (PCR) acting in series. The MBR contributed for approximately 70% to the overall slop purification. More precisely, the biological process was able to remove approximately 40%, on average, of the organic pollution in the slop. Nevertheless, the membrane was capable to retain a large amount of organic molecules within the system, amounting for a further 30% of the influent total organic content removal. However, this affected the membrane fouling, thus resulting in the increase of the pore blocking mechanism that accounted for approximately 20% to the total resistance to filtration (2.85∙10 13 m −1 ), even if a significant restoration of the original membrane permeability was obtained after chemical cleanings. On the other hand, the biological treatment produced a clear solution for the photocatalytic system, thereby optimizing the light penetration and generation of highly oxidizing active oxygen species that enabled the degradation of bio-recalcitrant compounds. Indeed, low total organic carbon (TOC) values (<10 mg L −1 ) were achieved in the output of the photocatalytic reactor by means of only 60 Einstein (E) of cumulative impinging energy after the addition of K 2 S 2 O 8 . Overall, coupling the two processes enabled very high TOC removal (ca. 95%)

    The Milk Yield by Cinisara Cows in Different Management Systems: 1. Effect of Season of Calving

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    The Cinisara cow is Sicilian autochthonous breed; the milk has very interesting qualitative characteristics (chemical, physical and technologic parameters, principally due to its high part β of K casein) and is processed to make Caciocavallo cheese. Characteristics of milk yield are influenced by exogenous factors, such as management system, lactation number and season of calving. Pastures provide the basic feed but grazing is not continuous through the year. The aim of this research was to optimize the distribution of production over the year through the study of the effect of season of calving on qualitative characteristics of milk from Cinisara cows on three farms located at different altitudes (P=plain, C=hill and M=mountain) near Trapani

    The Milk Yield by Cinisara Cows in Different Management Systems: 2. Effect of Season of Production

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    Cinisara is a Sicilian autochthonous breed of dairy cow. Qualitative characteristics of milk yield are influenced by composition of pasture and its changes over the seasons (Di Grigoli et al., 2000). The grazing resource is characterized by notable variability, even in adjacent areas, because of different environmental conditions, such as aspect, the nature of soil and altitude. The aim of this research is to study the effect of season of production on qualitative characteristics of Cinisara cow milk in farms located at different altitudes

    Thirty years of invasion: the distribution of the invasive crayfish Procambarus clarkii in Italy

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    The presence of the red swamp crayfish Procambarus clarkii in Italy is documented since 1989, but no comprehensive data are available on its spread through time at the national scale. New confirmed records for Procambarus clarkii are continuously arising in recent years across the country. By reviewing the scientific and grey literature, we obtained an up-to-date map of the species invasion in Italy. This information can help to monitor and understand the spread of this highly invasive crayfish and to implement more effective management measures

    A Distributed IoT Air Quality Measurement System for High-Risk Workplace Safety Enhancement

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    The safety of an operator working in a hazardous environment is a recurring topic in the technical literature of recent years, especially for high-risk environments such as oil and gas plants, refineries, gas depots, or chemical industries. One of the highest risk factors is constituted by the presence of gaseous substances such as toxic compounds such as carbon monoxide and nitric oxides, particulate matter or indoors, in closed spaces, low oxygen concentration atmospheres, and high concentrations of CO2 that can represent a risk for human health. In this context, there exist many monitoring systems for lots of specific applications where gas detection is required. In this paper, the authors present a distributed sensing system based on commercial sensors aimed at monitoring the presence of toxic compounds generated by a melting furnace with the aim of reliably detecting the insurgence of dangerous conditions for workers. The system is composed of two different sensor nodes and a gas analyzer, and it exploits commercial low-cost commercially available sensors

    Alcohol-Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts

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    The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent-free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst is synthesized by grafting 4-(4-(4-hydroxyphenylimino)cyclohexa-2,5dienylideneamino)phenol and silver nanoparticles onto the surface of moderately crystalline titanium dioxide. The titanium dioxide-based composite was first extensively characterized and then employed in the catalytic oxidation of 4-methoxybenzyl alcohol to 4-methoxybenzaldehyde under UV irradiation in water at room temperature. The corresponding aldehyde was obtained with unprecedented high selectivity (up to 86 %). The method is general and opens the route to fabrication of photocatalytic composites based on titanium dioxide functionalized with shuttle organic molecules and metal nanoparticles for a variety of oxidative conversions

    Pen shell Pinna nobilis L. (Mollusca: Bivalvia) from different peculiar environments: adaptive mechanisms of osmoregulation and neurotransmission

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    The pen shell Pinna nobilis (Linnaeus, 1758) is the largest endemic bivalve mollusc of the Mediterranean Sea, listed as an endangered species in the European Union. Because no information is available about the adaptation of pen shells to different habitats, herein the fundamental conditions of adaptation of P. nobilis to peculiar natural environments, such as the Strait of Messina (SM) and the meromictic Faro Lake (FL; Sicily, Italy), were explored by assessing the morphology, mucous production, osmoregulation and neurotransmission of their gills. Although gills of the pen shells from both sites exhibited a regular morphology, a higher presence of acid mucous cells was detected in P. nobilis from FL than SM, as well as higher levels of osmolytes but without interfering the osmoregulatory processes. About the functioning of gills, the cholinergic (i.e. acetylcholine and AChE) neuronal system was unaltered between individuals from the two sites, whereas the GABAergic neurotransmission (i.e. 4-aminobutyrate or GABA) was significantly augmented in gills of P. nobilis from FL than SM. This may be an adaptive response to hypoxic conditions in FL, as supported by the increased hypoxia-inducible factor (HIF-1α) in gills of pen shells from FL than SM. Noteworthy, this study reports for the first time the presence of the GABA neurotransmitter within the metabolite profile, obtained by application of a protonic Nuclear Magnetic Resonance (1H NMR)-based metabolomics approach, of a marine bivalve. Therefore, GABA may be suggested as a metabolite biomarker in pen shells. Overall, findings from this study provide new insights on the behavioural and adaptive responses of the pen shell Pinna nobilis settled in different peculiar environments

    Distance Traveled and Cross-State Commuting to Opioid Treatment Programs in the United States

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    This study examined commuting patterns among 23,141 methadone patients enrolling in 84 opioid treatment programs (OTPs) in the United States. Patients completed an anonymous one-page survey. A linear mixed model analysis was used to predict distance traveled to the OTP. More than half (60%) the patients traveled <10 miles and 6% travelled between 50 and 200 miles to attend an OTP; 8% travelled across a state border to attend an OTP. In the multivariate model (n = 17,792), factors significantly (P < .05) associated with distance were, residing in the Southeast or Midwest, low urbanicity, area of the patient's ZIP code, younger age, non-Hispanic white race/ethnicity, prescription opioid abuse, and no heroin use. A significant number of OTP patients travel considerable distances to access treatment. To reduce obstacles to OTP access, policy makers and treatment providers should be alert to patients' commuting patterns and to factors associated with them

    Comparative study of haematology of two teleost fish (Mugil cephalus and Carassius auratus) from different environments and feeding habits

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    Haematological parameters are valuable indicators of fish health status. This study is aimed to provide baseline data of the blood profile of two teleost fish species living in different environments and with divergent feeding behaviour, namely the flathead grey mullet Mugil cephalus Linnaeus, 1758, a marine herbivorous fish, and the goldfish Carassius auratus (Linnaeus, 1758), a freshwater omnivorous fish. Using an automated system coupled with flow cytometry and light microscopy, significant variations were found between M. cephalus and C. auratus blood parameters, except for haemoglobin concentration (Hgb). A significant increase in red blood cell count (RBC) and haematocrit (Hct) levels, associated with reduced mean corpuscular volume (MCV), was revealed in mullets in respect to goldfish. These data may be attributable to differences in fish species, or to their divergent physiological activeness as high RBC values are associated with fast movement and high activity with streamlined bodies, or to environmental factors such as water salinity, an increase in which may lead to erythropoiesis as an adaptive process in seawater fish. Additionally, lower values of white blood cell count (WBC) and thrombocyte count (TC) were recorded in mullets with respect to goldfish, and these changes may be due to divergent feeding habits of the two fish species, or to their different environments since increased salinity may inversely affect WBC. Overall, findings from this study provide a better understanding of the influences of divergent environmental conditions and feeding habits on fish blood parameters. The combined use of an automatic haematological count with flow cytometry was demonstrated to be effective for an early assessment of blood parameters in different fish species
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