Simultaneous removal of Cd,Co, Cu,Mn, Ni and Zn from synthetic solutions on a hemp‐based felt: Experimental design

The potential of using a hemp‐based material in felt form as an adsorbent for removing the metals from aqueous mixtures of Cd, Co, Cu, Mn, Ni, and Zn is investigated in the present study using batch experiments at an initial pH between 4.9 and 5.2. The operating variables studied were initial metal concentration, adsorbent dosage, contact time, agitation speed, temperature, presence of NaCl, and pH. Experiments showed that this nonconventional adsorbent exhibited interesting capacities: 1 g of hemp was able to remove 7.4 mg of metals at a concentration of 25 mg/L for each metal present in 100 mL of solution. Kinetic results showed that the process was uniform and rapid: adsorption of metals reached equilibrium in 10 min. The adsorption capacities were almost independent of temperature between 25 and 50 °C and pH between 4 and 6, but dependent on the presence of electrolytes such as NaCl. Interesting results were also obtained for real polymetallic effluents. All these findings are significant for the future development of hemp‐based materials for use as bag filters for metal removal from industrial effluents. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44422.     

Block and random copolyamides of poly(m‐xylylene adipamide) and poly(hexamethylene isophthalamide‐co‐terephthalamide): Methods of preparation and relationships between molecular structure and phase behavior

Copolymerization of poly(m‐xylylene adipamide) (MXD6) and poly(hexamethylene isophthalamide‐co‐terephthalamide) (PA6I‐6T) was used as an efficient strategy to prepare amorphous homogeneous systems with improved properties mainly for packaging applications. The preparation of block copolymers was first of all tried by co‐extrusion of the two polymers and then by thermal treatments at high temperatures in DSC or mixing in Brabender, also in the presence of a catalyst. The occurrence of transamidation reactions led to macromolecular structures with different randomness degrees. Further, random copolymers, with the full range of compositions, were synthetized from monomers, by a fast and simple two‐stage melt polycondensation. For all the copolymers, the sequence distribution was studied by using a ¹H NMR method developed by the Authors. The effects of preparation procedures, of mixing temperature and time, of the presence of a catalyst on the chemical structure, and, then, on final properties were studied. Interesting correlations among block length, monomer distribution and phase behavior were discussed. POLYM. ENG. SCI., SCI., 55:1475–1484, 2015. © 2014 Society of Plastics Engineers     

Preliminary design of the control and data acquisition systems for the Neutral Beam Test Facility

The Neutral Beam Test Facility, which will be built in Padova, Italy, is aimed at developing the ITER heating neutral beam injector (HNB) and at testing and optimizing its operation up to nominal performance before installation on ITER. It requires the development of two independent experiments referred to as SPIDER (source for production of ions of deuterium extracted from Rf plasma) and MITICA (megavolt ITer injector & concept advancement). SPIDER will explore the full-size negative ion source for ITER, whereas MITICA will explore the full-size ITER neutral beam injector. Both experiments will be designed for long-pulse operation, up to 3600 s, as ITER itself. MITICA includes three functional components: the heating neutral beam injector plant system (HNB), which is the device under test; the auxiliary plant system (AUX), which includes all equipment to operate the HNB in the test facility (e.g. the local electric grid to feed the HNB power supplies), and MITICA supervisory system that is an electronics/informatics infrastructure to operate the facility. The paper introduces the requirements for the control and data acquisition systems of the experiments and proposes a preliminary design for both systems. SPIDER, which is preparatory to MITICA and will be developed on a shorter time scale, has no constraints coming from ITER CODAC, whereas MITICA includes the ITER neutral beam injector and therefore must be fully compatible with ITER CODAC.     

Asymptotic Wave Propagation in a non-Newtonian Compressible Fluid with Small Dissipation

The spherical motion of a non-Newtonian compressible fluid is considered and a reductive perturbation method is used to study the point-explosion problem. The material response functions involved in the model under consideration are assumed to be of polynomial form and the resulting Burgers-like equation which governs the far-field approximation is investigated. A qualitative analysis of this equation is made via a numerical integration.     

Relation between ST-segment changes and myocardial perfusion evaluated by myocardial contrast echocardiography in patients with acute myocardial infarction treated with direct angioplasty

The aim of this study was to evaluate the relation between myocardial perfusion and ST-segment changes in patients with acute myocardial infarction treated with successful direct angioplasty. Thirty-seven patients, successfully treated with direct angioplasty, underwent myocardial contrast echocardiography before and after angioplasty. The sum of ST-segment elevation divided by the number of the leads involved (ST-segment elevation index) was calculated at 1, 5, 10, 20, and 30 minutes after restoration of a Thrombolysis In Myocardial Infarction trial grade 3 flow. After recanalization, myocardial reperfusion within the risk area was observed in 26 patients, whereas a no-reflow phenomenon occurred in 11. In patients with myocardial reperfusion, the ST-segment elevation index progressively declined, whereas in patients with no reflow, no significant change was observed. Reduction of > or = 50% in the ST-segment elevation index occurred in 20 of the 26 patients with reflow and in 1 of the 11 with no reflow (p = 0.0002). An additional increase of > or = 30% in the ST-segment elevation index occurred in 3 patients with reflow and in 7 with no reflow (p = 0.003). Sensitivity, specificity, positive and negative predictive values, and accuracy of the reduction in the ST-segment elevation index for predicting microvascular reflow were 77%, 91%, 95%, 62%, and 81%, respectively. The corresponding values of the increase in ST-segment elevation index for predicting no reflow were 64%, 88%, 70%, 85%, and 81%, respectively. In conclusion, after successful angioplasty, different patterns of myocardial perfusion are associated with different ST-segment changes. Analysis of ST-segment changes predicts the degree of myocardial reperfusion.     

Low-density lipoprotein oxidation and vitamins E and C in sustained and white-coat hypertension

Low-density lipoprotein oxidation and antioxidant vitamins E and C were investigated in white-coat hypertension in comparison with sustained hypertension and normotension. We selected 21 sustained hypertensive subjects, 21 white-coat hypertensive subjects, and 21 normotensive subjects matched for gender, age, and body mass index. White-coat hypertension was defined as clinical hypertension and daytime ambulatory blood pressure <139/90 (subjects were also reclassified using 134/90 and 135/85 mm Hg as cutoff points for daytime blood pressure). Blood samples were drawn for lipid profile determination, assessment of fluorescent products of lipid peroxidation in native LDL, evaluation of susceptibility to LDL oxidation in vitro (lag phase and propagation rate), and determination of LDL vitamin E and plasma vitamins E and C contents. Compared with sustained hypertensive subjects, white-coat hypertensives had significantly lower fluorescent products of lipid peroxidation (15.4+/-3.4 versus 10.2+/-3 units of relative fluorescence/mg LDL protein, P<.05), longer lag phase (54+/-10 versus 88+/-10 minutes, P<.05), lower propagation rate (8.2+/-2.5 versus 5.95+/-2.1 nmol diene/min per mg LDL cholesterol, P<.05), higher LDL vitamin E content (8.3+/-1.1 versus 10.1+/-1.8 nmol/mg LDL cholesterol, P<.05), and plasma vitamin C content (40+/-13 versus 57+9 micromol/L, P<. 05). No significant difference was observed between white-coat hypertensive and normotensive subjects. The results did not change after reclassification of subjects. Our data show that white-coat hypertensive subjects do not show an enhanced propensity to LDL oxidation or reduction in antioxidant vitamins. Given the role of LDL oxidation in the development of atherosclerosis and that of vitamin E and C in protecting against it, these findings suggest that white-coat hypertension per se carries a low atherogenic risk.     

Effect of thyroid function on LDL oxidation

OBJECTIVE: Serum gamma-glutamyltransferase (GGT) levels are raised in obese individuals, and a particularly strong association with central obesity has been described. We hypothesized that elevated GGT levels are a marker for visceral fat, and specifically for hepatic steatosis (fatty liver), and that hepatic steatosis leads to hepatic insulin resistance. To test this hypothesis, we examined the association between GGT levels and risk of NIDDM. RESEARCH DESIGN AND METHODS: We carried out a prospective cohort study of incident cases of doctor-diagnosed NIDDM in a group of 7,458 nondiabetic men (aged 40-59 years) followed for a mean of 12.8 years (range 11.5-13.0). The men were randomly selected from general practice lists in 24 British towns. Cases of NIDDM were ascertained by repeated postal questionnaires to the men and by regular systematic review of primary care records. RESULTS: A total of 194 men developed NIDDM during follow-up. Mean serum GGT at baseline (geometric mean [95% CI]) was significantly higher in the NIDDM patients than in the rest of the cohort (20.9 [19.3-22.6] vs. 15.3 U/l [15.0-15.6], P < 0.0001). There was a smooth, graded increase in the age-adjusted risk of NIDDM with increasing GGT levels, with a relative risk in the top fifth of the distribution of 6.8 (3.5-12.9) relative to the bottom fifth (trend P < 0.0001). This association was independent of serum glucose and BMI and of other predictors of NIDDM with which GGT is associated, including alcohol intake and physical activity level (adjusted upper to lower fifth relative risk: 4.8 [2.0-11.8], trend P < 0.0001]). CONCLUSIONS: These findings suggest that a raised serum GGT level is an independent risk factor for NIDDM. Serum GGT level may be a simple and reliable marker of visceral and hepatic fat and, by inference, of hepatic insulin resistance.