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This paper aims to identify the priorities on water sector planning. The priorities are identified by comparing the climate change impact on water consumption and the impact of using domestic water illegally to irrigate the urban agricultural holdings in suburban areas.

Metered water consumption in summer and winter in both urban and suburban areas was studied in Rafah city. A backward chronological linear model of climate change (precipitation and temperature) influence on water consumption was developed using software STATISTICA 10. The developed statistical relation was used to predict the impact of various climate change scenarios for domestic water consumption. Hence, four climate change scenarios were hypothesized – an increase in temperature by 1 and 20°C and a reduction in the rainfall by 10 and 20 per cent, respectively.

The most influential climate change scenario was the increase of temperature by 20°C, which caused an increase of 1.4 per cent on the average domestic water consumption compared to the current value. The hypothesized reduction of 20 per cent in precipitation caused a negligible increase in water consumption by 0.1 per cent from the current value. Urban agriculture and current practice of using municipal water to irrigate cultivated urban holdings have a significant negative influence on domestic water consumption. The aforementioned practice led to a high percentage of unaccounted for water (UFW) of 33, 38 and 45 per cent for the years 2010, 2011 and 2012, respectively.

The concerned decision-makers should consider the right track in prioritizing dilemmas for planning water sector in suburban areas.

This research could be considered the first of its kind because impacts of urban agriculture and climate change on domestic water consumption have never been previously considered in the Gaza Strip.

Corrosion resistance measurements were performed on AISI 316L stainless steel biomaterial samples after three types of treatments: abrasive finishing (MP), standard electropolishing (EP), and magnetoelectropolishing (MEP). The corrosion studies were carried out in Ringer's solution at a room temperature. Potentiodynamic plots obtained were the basis for the analysis of measurement accuracy and uncertainty with the statistical tests results done in Statistica 64/10 software. The results of corrosion studies indicate a significant difference in the breaking potential (Epit) values, dependent on surface treatment. The highest mean values have been obtained on samples after MEP (Epit=961 mV), much lower – after a standard electropolishing EP (Epit=525 mV), and the lowest – after the abrasive treatment MP (Epit=222 mV), all of them measured against a saturated calomel electrode SCE potential. The corrosion results obtained are well correlated with the nanoindentation measurement results (Young's modulus and nanohardness). The paper aims to discuss these issues.

The AISI 316L austenitic stainless steel samples served for the study. There were 11 (MP) and 14 (EP) samples used for each of the treatment, and 31 samples used for magnetoelectropolishing MEP. All polarization measurements were made after one hour immersion in the Ringer's solution. Statistical tests were used to treat the results obtained.

After magnetoelectropolishing MEP130, the pitting corrosion resistance is much better than that after abrasive polishing MP and/or a standard electropolishing EP130. It was proved on a big statistical sample that the pitting corrosion potential Epit after MEP130 is over 1.8 times higher than that after EP130 and over 4.3 times higher than that after MP. The results obtained are in good agreement with the nanoindentation measurement results.

This is an original study of the corrosion resistance of AISI 316L SS in Ringer's solution. The breaking potential Eb obtained is comparable with that of NiTi alloys, not reported anywhere before. The results have been well confirmed statistically (on 31 samples after MEP).

Nel riprendere come Libero Docente le mie lezioni presso la Facoltà di Giurisprudenza dopo un lungo intervallo di anni in cui il Corso è stato impartito per Incarico, cioè a titolo ufficiale, prima nella facoltà di Scienze Politiche e poi in quella di Economia e Commercie, ritengo opportuno accennare alle vicende di questo insegnamento che ha segnato in certo modo il punto di partenza ed insieme il banco di prova del primo tentativo di sistematica scientifica della trattazione del turismo dal punto di vista economico e statistico. E mancherei ad un preciso dovere e ad un impulso spontaneo del mio animo se in questa occasione non rivolgessi un memore e devoto pensiero al mio grande ed indimenticabile maestro, Augusto Graziani, che seppe inculcarmi la passione per gli studi di economia politica: debbo anzi a lui anche lo specifico orientamento verso l'indagine turistica, perchè il primo tema che egli mi propose nelle esercitazioni di seminario degli Istituti Giuridici dell'Università di Napoli (oh magnifica palestra per noi giovanissimi studenti appena usciti dal Liceo!) fu quello della bilancia dei pagamenti internazionali con particolare riguardo alle cosidette partite «invisibili».

The purpose of this study is to investigate the corrosion inhibition of mild steel alloy in 2 M H₃PO₄ solution by the pomegranate peel extract as a friendly inhibitor was studied at various temperatures, inhibitor concentrations and immersion times.

A weight loss method was used to evaluate the corrosion rate. The experimental Taguchi design method was used for the distribution of experiments. The experimental design gave results which were impossible to show graphically. However, this problem was solved effectively with the aid of regression analysis.

Corrosion rate increased with temperature according to Arrhenius equation. It was found that the efficiency of inhibition was increased with an increase in the concentration of inhibitor and immersion time. However, this diminishes with increased temperature. According to Langmuir isotherm, the inhibitor was adsorbed physically on steel surface. The negative sign of estimated heat of adsorption suggests a stable spontaneous inhibition process. Combination of mathematical and statistical analysis was proposed to demonstrate the results of corrosion rate with high correlation coefficients. In addition, Fourier transform infrared spectrometer examinations confirmed that the organic inhibitor consists of phenolic components as main materials.

Using unconventional approach for evaluation of environmentally friendly inhibitor for corrosion of mild steel in phosphoric acid solution.

This paper aims to study the effects of a diet supplemented with flaxseeds on dyslipidemia, oxidative stress and proinflammatory cytokines, in rats consuming a high-cholesterol diet.

Male Wistar rats (n = 30) weighing (250 ± 5 g) of which 10 were control and 20 were rendered hypercholesterolemic (HC) by feeding a diet enriched with 1% of cholesterol, for 15 days. After this phase, rats were divided into two groups; hypercholesterolemic group (HC) (n = 10), fed 20% casein diet enriched with 1% cholesterol; and hypercholesterolemic rats fed the same diet (n = 10), but additionally supplemented with flaxseeds (Linum usitatissimum) (Lu) powder, i.e. HC-Lu. Animals of the control group (n = 10) were fed the casein diet. All the animals were maintained on the respective diets for four weeks.

This study showed that in HC-Lu as compared to HC group, plasma total cholesterol, triacylglycerols and non-HDL cholesterol concentrations were respectively 2.4-, 1.5- and 3-fold lower. Also, the lipid peroxidation was reduced in red blood cells, organs (liver, heart and aorta) and lipoproteins (HDL2, HDL3 and VDL-LDL). A higher superoxide dismutase activity was observed in liver (+61%), heart (+62%) and aorta (+59%), whereas plasma proinflammatory cytokine (IL-1beta and IL-6) levels were decreased.

These results suggest that flaxseeds help to reduce hypercholesterolemia, oxidative stress and inflammation in patients with hypercholesterolemia.

The authors propose to estimate a varying coefficient panel data model with different smoothing variables and fixed effects using a two-step approach. The pilot step estimates the varying coefficients by a series method. We then use the pilot estimates to perform a one-step backfitting through local linear kernel smoothing, which is shown to be oracle efficient in the sense of being asymptotically equivalent to the estimate knowing the other components of the varying coefficients. In both steps, the authors remove the fixed effects through properly constructed weights. The authors obtain the asymptotic properties of both the pilot and efficient estimators. The Monte Carlo simulations show that the proposed estimator performs well. The authors illustrate their applicability by estimating a varying coefficient production frontier using a panel data, without assuming distributions of the efficiency and error terms.

The purpose of this study is to determine the effect of olive cake (OC) on lipid peroxidation as well as antioxidant enzymes activities of serum, red blood cells (RBCs) and liver, in streptozotocin (STZ)-induced-diabetic rat fed cholesterol-enriched diet.

Hypercholesterolemic male rats were rendered diabetic (HC-D) by a single intraperitoneal injection dose of STZ (35 mg/kg BW). HC-D rats were divided into two groups fed for 28d a diet supplemented with OC at 7.5 percent (HC-D-OC) or not (HC-D). A control group (C) was submitted to standard diet containing 20 per cent casein for the same experimental period.

RBCs, serum and liver thiobarbituric acid reactive substances (TBARS) contents were significantly increased in HC-D, compared to C group (p = 0.04, p = 0.02 and 0.03). These values were significantly decreased (48 per cent and 64 per cent; p = 0.02 and p = 0.0007) in serum and liver of HC-D-OC vs HC-D group. In RBCs, superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) activities were, respectively, 1.5, 2- and 1.7-fold higher (p = 0.03, p = 0.008 and p = 0.03) in HC-D group compared to HC group. In serum and liver, SOD, CAT and GST activities were, respectively, 1.3-, 2.6- and 1.6-fold increased (p = 0.03, p = 0.007 and p = 0.02). In HC-D-OC compared to HC-D group, RBCs glutathione peroxidase (GSH-Px), CAT and GST activities were, respectively, 2.1-, 3.3- and 2.1-fold higher (p = 0.04, p = 0.0009 and p = 0.03). In serum, SOD and CAT activities were, respectively, 1.5- and 1.9-fold increased (p = 0.02, p = 0.02). In liver, SOD, GSH-PX, CAT and GST activities were significantly increased (p = 0.005, p = 0.03, p = 0.02 and p = 0.04).

In diabetic rats-fed cholesterol-enriched diet, OC was able to reduce oxidative stress by decreasing lipid peroxidation and increasing antioxidant enzymes activities in serum, RBCs and liver.

The purpose of this paper is to substitute wheat flour by passion fruit peel flour in Brazilian honey bread (pão de mel), with evaluation of the breads’ sensory features, chemical composition and physical properties.

Honey breads with wheat flour (standard) and with replacement of this ingredient by 10 to 50 per cent passion fruit peel flour were produced. Two sensory tests were applied, to identify how different formulations with passion fruit peel flour were when compared to the standard formulation, and also the acceptability of the products. The selected honey breads, through sensory results, were evaluated regarding to chemical composition and physical properties.

Formulations with 10 and 20 per cent substitution were the least different to formulations with only wheat flour, and were as acceptable as the wheat flour sample. Physical and chemical characteristics of breads with 10 and 20 per cent passion fruit peel flour were similar; however, honey bread with 20 per cent passion fruit peel flour had higher fibre content, ash quantity and hardness value; a lower specific volume; and a different colour from the wheat flour sample.

This study offers an opportunity to food industries through utilization of an agro-industrial by-product on the formulation of a Brazilian traditional product.

This study presents the feasibility of using an agro-industrial by-product to Brazilian honey bread, enhancing the nutritive value of this product and reducing the impact of passion fruit peel flour on the environment.

This paper aims to evaluate the material properties and dimensional accuracy of a MakerBot Replicator 2 desktop 3D printer.

A design of experiments (DOE) test protocol was applied to determine the effect of the following variables on the material properties of 3D printed part: layer height, per cent infill and print orientation using a MakerBot Replicator 2 printer. Classical laminate plate theory was used to compare results from the DOE experiments with theoretically predicted elastic moduli for the tensile samples. Dimensional accuracy of test samples was also investigated.

DOE results suggest that per cent infill has a significant effect on the longitudinal elastic modulus and ultimate strength of the test specimens, whereas print orientation and layer thickness fail to achieve significance. Dimensional analysis of test specimens shows that the test specimen varied significantly (p < 0.05) from the nominal print dimensions.

Although desktop 3D printers are an attractive manufacturing option to quickly produce functional components, this study suggests that users must be aware of this manufacturing process’ inherent limitations, especially for components requiring high geometric tolerance or specific material properties. Therefore, higher quality 3D printers and more detailed investigation into the MakerBot MakerWare printing settings are recommended if consistent material properties or geometries are required.

Three-dimensional (3D) printing is a rapidly expanding manufacturing method. Initially, 3D printing was used for prototyping, but now this method is being used to create functional final products. In recent years, desktop 3D printers have become commercially available to academics and hobbyists as a means of rapid component manufacturing. Although these desktop printers are able to facilitate reduced manufacturing times, material costs and labor costs, relatively little literature exists to quantify the physical properties of the printed material as well as the dimensional consistency of the printing processes.

This paper aims to present a comprehensive analysis of deburring effectiveness and surface layer properties after deburring process by wire brushing from milled 7075 aluminium alloys objects. Edge states (rounding, chamfering), surface roughness around the edge, microhardness and residual stress distribution were analyzed.

During the machining process, undesirable phenomenon occurs, which is the formation of burrs at the edges of workpieces. They occur in most elements formed by machining. There are many methods that can be used for deburring, but in the case of large components, typical of aerospace industry, using certain methods becomes difficult or uneconomic. Taking advantage of the fact that a part is mounted on the machine, it is advisable to make deburring operation the last action. This operation can be carried out by wire brushing.

On the basis of conducted studies, it was demonstrated that it was possible to choose such technological brushing conditions as to ensure an effective process of deburring, form appropriate edge state and generate the desired surface layer properties.

The method presented in the article allows for efficient, automatic deburring, especially for large components made of 7075 aluminium alloy. This eliminates manual, time-consuming methods of removing burrs by locksmiths. Moreover, the results allow to evaluate changes occurring in the surface layer after brushing process.

Results of brushing experiment provide full information on selection of technological parameters to obtain the required surface roughness and edge state. Moreover, analysis of surface layer properties (microhardness, residual stress) allows to assess the degree of impact hitting fibre on the workpiece.