Evaluation of organic matter stability during the composting process of agroindustrial wastes.

Composting of wastes from citrus industrial processing (pastazzo and sludge) was studied in order to evaluate the evolution of organic matter during the process and to individuate chemical and/or biochemical techniques able to set the stability of the final product. Composts from two open-air piles of different composition were sampled every month during the whole period of composting (5 months) and the organic matter of each sample was characterised by chemical and biochemical techniques. Humification rate (HR%) and humification index (HI) were determined. Extracted organic matter of six samples collected for each compost was investigated by isoelectric-focusing technique (IEF). The biochemical analysis was based on the study of C-mineralisation after the addition of each collected sample to soil. Results obtained clearly demonstrated organic matter evolution during composting processes. Humification rates increased and humification indexes decreased over time, while extracted organic matter showed electrophoretic behaviour typical of stabilised organic compounds. Moreover, mineralisation patterns confirmed the increased level of organic matter stability during the composting process

Searching for Non-monotonic Effects of Fiscal Policy: New Evidence

Data revisions and the availability of a longer sample offer the opportunity to reconsider empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a "large and persistent impulse," defined as one in which the full employment surplus, as a percentage of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less than complete, offset during expansions or contractions.

Searching for Non-Monotonic Effects of Fiscal Policy: New Evidence

Data revisions and the availability of a longer sample offer the opportunity to reconsider the empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a “large and persistent impulse”, defined as one in which the full employment surplus, as a percent of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less then complete, offset during expansions or contractions.Fiscal policy, national saving

Searching for Non-Monotonic Effects of Fiscal Policy: New Evidence

Data revisions and the availability of a longer sample offer the opportunity to reconsider the empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a "large and persistent impulse", defined as one in which the full employment surplus, as a percent of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less then complete, offset during expansions or contractions.

Inter-Element Crack Propagation with High-Order Stress Equilibrium Element

The present contribution proposes a formulation based on the use of hybrid equilibrium elements (HEEs), for the analysis of inter-element delamination and fracture propagation problems. HEEs are defined in terms of quadratic stress fields, which strongly verify both the homogeneous and inter-element equilibrium equations and they are employed with interfaces, initially exhibiting rigid behavior, embedded at the elements’ sides. The interface model is formulated in terms of the same degrees of freedom of the HEE, without any additional burden. The cohesive zone model (CZM) of the extrinsic interface is rigorously developed in the damage mechanics framework, with perfect adhesion at the pre-failure condition and with linear softening at the post-failure regime. After a brief review, the formulation is computationally tested by simulating the behavior of a double-cantilever-beam with diagonal loads; the obtained numerical results confirm the accuracy and potential of the method

An Analytical Analysis of CDT Coupled to Dimer-like Matter

We consider a model of restricted dimers coupled to two-dimensional causal dynamical triangulations (CDT), where the dimer configurations are restricted in the sense that they do not include dimers in regions of high curvature. It is shown how the model can be solved analytically using bijections with decorated trees. At a negative critical value for the dimer fugacity the model undergoes a phase transition at which the critical exponent associated to the geometry changes. This represents the first account of an analytical study of a matter model with two-dimensional interactions coupled to CDT.Comment: 12 pages, many figures, shortened, as publishe

Environmental contaminants exposure and preterm birth: a systematic review

Preterm birth is an obstetric condition associated with a high risk of infant mortality and morbidities in both the neonatal period and later in life, which has also a significant public health impact because it carries an important societal economic burden. As in many cases the etiology is unknown, it is important to identify environmental factors that may be involved in the occurrence of this condition. In this review, we report all the studies published in PubMed and Scopus databases from January 1992 to January 2019, accessible as full-text articles, written in English, including clinical studies, original studies, and reviews. We excluded articles not written in English, duplicates, considering inappropriate populations and/or exposures or irrelevant outcomes and patients with known risk factors for preterm birth (PTB). The aim of this article is to identify and summarize the studies that examine environmental toxicants exposure associated with preterm birth. This knowledge will strengthen the possibility to develop strategies to reduce the exposure to these toxicants and apply clinical measures for preterm birth prevention