Pass-transistor based implementations of threshold logic gates for WOS filtering

This paper presents a systematic procedure to implement threshold functions by using a pass-transistor network. A main feature of the threshold gates (TGs) produced by this technique is that they do not exhibit the fan-in limitations usual when other implementation techniques are used. Thus, they are especially useful for Weighted Order Statistical (WOS) filters because the binary filters required are threshold functions which usually present a high total sum of weights. A WOS filter with its binary filters implemented as pass-transistor TGs is demonstrated in an standard 0.35 μm CMOS technology at 3.3 V. The filter shows a sample frequency well over 100 MHz at the nominal process condition and it is cheaper, faster and consumes less power than a conventional approach.     

Depression and memory impairment: A meta-analysis of the association, its pattern, and specificity.

The existing evidence paints an unclear picture of whether an association exists between depression and memory impairment. The purpose of this investigation was to determine whether depression is associated with memory impairment, whether moderator variables determine the extent of this association, and whether any obtained association is unique to depression. Meta-analytic techniques were used to synthesize data from 99 studies on recall and 48 studies on recognition in clinically depressed and nondepressed samples. Associations between memory impairment and other psychiatric disorders (e.g., schizophrenia, dementia) were also examined. A significant, stable association between depression and memory impairment was revealed. Further analyses indicated, however, that it is likely that depression is linked to particular aspects of memory, the linkage is found in particular subsets of depressed individuals, and memory impairment is not unique to depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of obesity on the response to insulin therapy in noninsulin-dependent diabetes mellitus

An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol.     

Culture of Helicobacter pylori from gastric biopsies transported in biopsy urease test tubes

Gastric biopsy specimens of 57 consecutively observed dyspeptic patients were studied for the presence of Helicobacter pylori by histological examination, biopsy urease test (BUT) and culture. For culture, biopsy samples were transported in both Stuart media and BUT tubes. All 15 isolates could be cultured from both Stuart and BUT tubes. Thus, if the main reason for culture of Helicobacter pylori is for antimicrobial susceptibility testing, only positive BUT tubes need to be submitted. This would reduce both the expense and the number of biopsies needed.     

Polymers,composites, and characterization of conducting polyfuran and poly(2‐bromoaniline)

Polyfuran (PFu), poly(2‐bromoaniline) (P2BrAn), and poly(2‐bromoaniline)/polyfuran (P2BrAn/PFu) composites were synthesized by coupling using various solvents and oxidants. 2‐Bromoaniline (2BrAn) was polymerized using FeCl₃ and (NH₄)₂S₂O₈ in aqueous HCl medium. PFu was synthesized using FeCl₃ and SbCl₃ in anhydrous media (CHCl₃, CH₃CN). Furan was polymerized using both salts in CHCl₃ medium, whereas it could be polymerized using only FeCl₃ in CH₃CN medium. The new electrically conducting composites were prepared by chemical oxidative polymerization using polyfuran synthesized with SbCl₃ and poly(2‐bromoaniline). The polymers and composites were characterized using conductivity, magnetic susceptibility, infrared spectra (FTIR), UV‐Vis spectra, thermal analysis (TGA), and scanning electron microscopy (SEM) measurements. It was found that PFu(SbCl₃) has the lowest thermal stability. Thus, the thermal stability of PFu was increased by preparing composites. The chemical structures of P2BrAns and composites have been found from UV‐Vis results to contain quinone‐imine units along the polymer chain. Magnetic susceptibility measurements indicated that the polymers and composites were diamagnetic or paramagnetic. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2048–2057, 2005     

A New Application of Solvent Extraction to Separate Copper from Extreme Acid Mine Drainage Producing Solutions for Electrochemical and Biological Recovery Processes

Over the last decade, AMD waters have gained more attention as a potential source of metals due to the emerging need to recover or recycle metals from secondary resources. Metals recovery supports sustainability and the development of a circular economy with benefits for resource conservation and the environment. In this study, five extractants (Acorga M5640, LIX 54, LIX 622, LIX 622 N, and LIX 864) diluted (15% (v/v)) in Shell GTL with 2.5% (v/v) octanol were compared and evaluated for Cu recovery from an extreme AMD sample (5.3?±?0.3 g/L Cu) collected at the inactive São Domingos Mine in the Iberian Pyrite Belt of Portugal. Of the five extractants, Acorga M5640 showed the best selective efficiency. Further tests showed that 30% (v/v) of this extractant was able to selectively extract ≈ 96.0% of the Cu from the AMD in one extraction step and all of the remaining Cu (to below detection) in three steps. Among the different stripping agents tested, 2 M sulfuric acid was the most efficient, with ≈ 99% of the Cu stripped, and the recyclability of the organic phase was confirmed in five successive cycles of extraction and stripping. Furthermore, contact time tests revealed that the extraction kinetics allows the transfer of ≈ 97% of the Cu in 15 min, and aqueous to organic phase ratios tests demonstrated a maximum loading capacity of ≈ 16 g/L Cu in the organic phase. Raising the concentration of Cu in the stripping solution (2 M sulfuric acid) to ≈ 46 g/L through successive striping steps showed the potential to recover elemental Cu using traditional electrowinning. Finally, a biological approach for Cu recovery from the stripping solution was evaluated by adding the supernatant of a sulfate-reducing bacteria culture to make different molar ratios of biogenic sulfide to copper; ratios over 1.75 resulted in precipitation of more than 95% of the Cu as covellite nanoparticles.

Graphical Abstract