206 research outputs found
Monitoring Soil Salinisation as a Strategy for Preventing Land Degradation: A Case Study in Sicily, Italy
Influence of biochar on the physical, chemical and retention properties of an amended sandy soil
Soil porosity plays an important role in soil-water retention and water availability to crops, potentially affecting
both agricultural practices and environmental sustainability. The pore structure controls fluid flow and transport
through the soil, as well as the relationship between the properties of individual minerals and plants. Moreover,
the anthropogenic pressure on soil properties has produced numerous sites with extensive desertification process
close to residential areas.
Biochar (biologically derived charcoal) is produced by pyrolysis of biomasses under low oxygen conditions,
and it can be applied for recycling organic waste in soils and increase soil fertility, improving soil structure and
enhancing soil water storage and soil water movement.
Soil application of biochar might have agricultural, environmental and sustainability advantages over the use of
organic manures or compost, as it is a porous material with a high inner surface area.
The main objectives of the present study were to investigate the possible application of biochar from forest
residues, derived from mechanically chipped trunks and large branches of Abies alba M., Larix decidua Mill.,
Picea excelsa L., Pinus nigra A. and Pinus sylvestris L. pyrolysed at 450 C for 48h, to improve soil structural and
hydraulic properties (achieving a stabilization of soil).
Different amount of biochar were added to a desertic sandy soil, and the effect on soil porosity water retention and
water available to crops were investigated.
The High Energy Moisture Characteristic (HEMC) technique was applied to investigate soil-water retention
at high-pressure head levels. The adsorption and desorption isotherms of N2 on external surfaces were also
determined in order to investigate micro and macro porosity ratio.
Both the described model of studies on adsorption-desorption experiments with the applied isotherms model
explain the increasing substrate porosity with a particular attention to the macro and micro porosity, respectively
Cathepsin D expression levels in nongynecological solid tumors: Clinical and therapeutic implications
Cathepsin D is a lysosomal acid proteinase which is involved in the malignant progression of breast cancer and other gynecological tumors. Clinical investigations have shown that in breast cancer patients cathepsin D overexpression was significantly correlated with a shorter free-time disease and overall survival, whereas in patients with ovarian or endometrial cancer this phenomenon was associated with tumor aggressiveness and a degree of chemoresistance to various antitumor drugs such as anthracyclines, cis-platinum and vinca alkaloids. Therefore, a lot of research has been undertaken to evaluate the role and the prognostic value of cathepsin D also in other solid neoplasms. However, conflicting results have been generated from these studies. The discrepancies in these results may, in part, be explained with the different methodological approaches used in order to determine the levels of expression of the enzyme in tumor tissues and body fluids. Further investigations using well-standardized techniques may better define the clinical significance of cathepsin D expression in solid tumors. Nevertheless, evidence emerging from these studies indicates that this proteinase seems to facilitate early phases of tumor progression such as cell proliferation and local dissemination. These findings support the concept that cathepsin D may be a useful marker for identifying patients with highly malignant tumor phenotypes who may need more aggressive clinical treatment; this enzyme may also be considered as a potential target for a novel therapeutic approach in the treatment of solid neoplasms
How Organizational Resources and Managerial Features Affect Business Performance: An Analysis in the Greek Wine Industry
Despite the growing interest of the wine industry in quality and environmental certifications and the influence of these standards on positioning in international markets, scholarly research has paid proportionally limited attention to the link between winery export intensity and the adoption of internationally recognized standards. This study aims to analyze which factors make an organizational model performant, and to verify the impact of the adoption of third-party certifications on the export performance by using the resource-based view (RBV) theory as a theoretical lens. Findings show that younger wineries are more oriented towards the adoption of voluntary quality and environmental certifications, and they achieve the best economic performance, expressed in terms of overall turnover on the market. On the contrary, the better export performance is achieved by the largest group of wineries, which make the greatest effort in promotion and advertising activities and sell their products through intermediaries, while showing a low adoption of certifications. Our results have a number of theoretical and practical implications
Modulation of NRF2/KEAP1 Signaling in Preeclampsia
Placentation is a key and tightly regulated process that ensures the normal development of the placenta and fetal growth. Preeclampsia (PE) is a hypertensive pregnancy-related disorder involving about 5–8% of all pregnancies and clinically characterized by de novo maternal hypertension and proteinuria. In addition, PE pregnancies are also characterized by increased oxidative stress and inflammation. The NRF2/KEAP1 signaling pathway plays an important role in protecting cells against oxidative damage due to increased reactive oxygen species (ROS) levels. ROS activate NRF2, allowing its binding to the antioxidant response element (ARE) region present in the promoter of several antioxidant genes such as heme oxygenase, catalase, glutathione peroxidase and superoxide dismutase that neutralize ROS, protecting cells against oxidative stress damages. In this review, we analyze the current literature regarding the role of the NRF2/KEAP1 pathway in preeclamptic pregnancies, discussing the main cellular modulators of this pathway. Moreover, we also discuss the main natural and synthetic compounds that can regulate this pathway in in vivo and in vitro models
Limits to Sympathetic Evaporative Cooling of a Two-Component Fermi Gas
We find a limit cycle in a quasi-equilibrium model of evaporative cooling of
a two-component fermion gas. The existence of such a limit cycle represents an
obstruction to reaching the quantum ground state evaporatively. We show that
evaporatively the \beta\mu ~ 1. We speculate that one may be able to cool an
atomic fermi gas further by photoassociating dimers near the bottom of the
fermi sea.Comment: Submitted to Phys. Rev
Vitamin D in cancer chemoprevention
Context: There is increasing evidence that Vitamin D (Vit D) and its metabolites, besides their well-known calcium-related functions, may also exert antiproliferative, pro-differentiating, and immune modulatory effects on tumor cells in vitro and may also delay tumor growth in vivo.
Objective: The aim of this review is to provide fresh insight into the most recent advances on the role of Vit D and its analogues as chemopreventive drugs in cancer therapy.
Methods: A systematic review of experimental and clinical studies on Vit D and cancer was undertaken by using the major electronic health database including ISI Web of Science, Medline, PubMed, Scopus and Google Scholar.
Results and conclusion: Experimental and clinical observations suggest that Vit D and its analogues may be effective in preventing the malignant transformation and/or the progression of various types of human tumors including breast cancer, prostate cancer, colorectal cancer, and some hematological malignances. These findings suggest the possibility of the clinical use of these molecules as novel potential chemopreventive and anticancer agent
Analytical Estimate of the Critical Velocity for Vortex Pair Creation in Trapped Bose Condensates
We use a modified Thomas-Fermi approximation to estimate analytically the
critical velocity for the formation of vortices in harmonically trapped BEC. We
compare this analytical estimate to numerical calculations and to recent
experiments on trapped alkali condensates.Comment: 12 page
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