Adsorption of Cu(II) on Araucaria angustifolia wastes: determination of the optimal conditions by statistic design of experiments

Wastes of Araucaria angustifolia (named pinh?o) natural (PW) and also loaded with Congo red (CRP) were tested as low-cost adsorbents for Cu(II) removal from aqueous solutions. In order to reduce the total number of experiments to achieve the best conditions of the batch adsorption procedure, three sets of statistical designs of experiments were carried-out for each adsorbent. Initially, a full 2(4) factorial design for each adsorbent with two central points (18 experiments) were performed, to optimize the following factors: mass of adsorbent (m), pH, time of contact (t) and initial metallic ion concentration (Co). These results indicated that almost all the main factors and its interactions were significant. It was verified for both adsorbents, that a mass of 30.0mg leaded to higher Cu(II) uptake and that the best pH for Cu(II) adsorption was 5.6. In order to continue the batch adsorption optimization of the systems, a central composite surface analysis design with two factors (Co, t) containing 13 experiments, divided in to four cube points, four axial points and five centre points was carried-out for each adsorbent. By performing these two sets of statistical design of experiments, the best conditions for Cu(II) uptake using pinh?o wastes (PW) and pinh?o wastes loaded with Congo red (CRP) using batch adsorption system, where: m=30.0mg of adsorbent; pH 5.6; t=2.5h. After optimizing the batch adsorption system by statistical design of experiments, isotherms for Cu(II) uptake using PW and CRP were performed. These isotherms fitted to the linear Langmuir and Freundlich models.     

Protein-repellent silicon nitride surfaces: UV-induced formation of oligoethylene oxide monolayers

The grafting of polymers and oligomers of ethylene oxide onto surfaces is widely used to prevent nonspecific adsorption of biological material on sensors and membrane surfaces. In this report, we show for the first time the robust covalent attachment of short oligoethylene oxide-terminated alkenes (CH(3)O(CH(2)CH(2)O)(3)(CH(2))(11)-(CH═CH(2)) [EO(3)] and CH(3)O(CH(2)CH(2)O)(6)(CH(2))(11)-(CH═CH(2)) [EO(6)]) from the reaction of alkenes onto silicon-rich silicon nitride surfaces at room temperature using UV light. Reflectometry is used to monitor in situ the nonspecific adsorption of bovine serum albumin (BSA) and fibrinogen (FIB) onto oligoethylene oxide coated silicon-rich silicon nitride surfaces (EO(n)-Si(x)N(4), x > 3) in comparison with plasma-oxidized silicon-rich silicon nitride surfaces (SiO(y)-Si(x)N(4)) and hexadecane-coated Si(x)N(4) surfaces (C(16)-Si(x)N(4)). A significant reduction in protein adsorption on EO(n)-Si(x)N(4) surfaces was achieved, adsorption onto EO(3)-Si(x)N(4) and EO(6)-Si(x)N(4) were 0.22 mg m(-2) and 0.08 mg m(-2), respectively. The performance of the obtained EO(3) and EO(6) layers is comparable to those of similar, highly protein-repellent monolayers formed on gold and silver surfaces. EO(6)-Si(x)N(4) surfaces prevented significantly the adsorption of BSA (0.08 mg m(-2)). Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), X-ray reflectivity and static water contact angle measurements were employed to characterize the modified surfaces. In addition, the stability of EO(6)-Si(x)N(4) surfaces in phosphate-buffered saline solution (PBS) and alkaline condition (pH 10) was studied. Prolonged exposure of the surfaces to PBS solution for 1 week or alkaline condition for 2 h resulted in only minor degradation of the ethylene oxide moieties and no oxidation of the Si(x)N(4) substrates was observed. Highly stable antifouling coatings on Si(x)N(4) surfaces significantly broaden the application potential of silicon nitride-coated microdevices, and in particular of microfabricated filtration membranes.     

为医疗保健实现移动性:我们为何需要“医疗级无线设备”

可以通过加速提供无线医疗解决方案来削减卫生保健成本。为了实现这个目标,需要一种随处可见且可靠的无线基础设施一种设备,能够构建框架,从而无论病患身在何处,都可以在适当的时候获得适当的护理。     

Plastics disassembly versus bulk recycling: engineering design for end-of-life electronics resource recovery

Annual plastic flows through the business and consumer electronics manufacturing supply chain include nearly 3 billion lb of high-value engineering plastics derived from petroleum. The recovery of resource value from this stream presents critical challenges in areas of materials identification and recycling process design that demand new green engineering technologies applied together with life cycle assessment and ecological supply chain analysis to create viable plastics-to-plastics supply cycles. The sustainable recovery of potentially high-value engineering plastics streams requires that recyclers either avoid mixing plastic parts or purify later by separating smaller plastic pieces created in volume reduction (shredding) steps. Identification and separation constitute significant barriers in the plastics-to-plastics recycling value proposition. In the present work, we develop a model that accepts randomly arriving electronic products to study scenarios by which a recycler might identify and separate high-value engineering plastics as well as metals. Using discrete eventsimulation,we compare current mixed plastics recovery with spectrochemical plastic resin identification and subsequent sorting. Our results show that limited disassembly with whole-part identification can produce substantial yields in separated streams of recovered engineering thermoplastics. We find that disassembly with identification does not constitute a bottleneck, but rather, with relatively few workers, can be configured to pull the process and thus decrease maximum staging space requirements.     

International variation in clinical injury incidence: exploring the performance of indicators based on health care, anatomical and outcome criteria

OBJECTIVE: To analyse international variation in clinical injury incidence, and explore the performance of different injury indicators in cross-country comparisons. METHODS: Hospital discharge data of seven European countries (Austria, Denmark, Ireland, Netherlands, Norway, England and Wales) were analysed. We tested existing and newly developed indicators based on (a) health care use, (b) anatomical criteria, or (c) expected health outcome: admissions excluding day-cases (a), hospital stay 4+ (a) and 7+ days (a), (serious) long-bone fractures (b), selected radiological verifiable fractures 'SRVFs' (b), and indicators based on international (Global Burden of Disease) and Dutch disability weights). Assessment criteria were reduction in incidence variation and length of stay in hospital, and the association between incidence and mortality rates. RESULTS: Indicators based on health care use led to increased variation in incidence rates. Long bone fractures and SRVFs, and both indicators based on injuries with moderate to high disability showed similar variation in clinical incidence compared to the crude rates, smaller variation in median length of stay in hospital and a good association with mortality rates. CONCLUSION: No perfect or near perfect indicators of clinical injury incidence exist. For international comparisons, indicators based on disability weights, SRVFs and long bone fractures may be sensible indicators to use, in the absence of a direct measure of anatomical severity.     

Mindfulness-based cognitive therapy to prevent relapse in recurrent depression.

For people at risk of depressive relapse, mindfulness-based cognitive therapy (MBCT) has an additive benefit to usual care (H. F. Coelho, P. H. Canter, & E. Ernst, 2007). This study asked if, among patients with recurrent depression who are treated with antidepressant medication (ADM), MBCT is comparable to treatment with maintenance ADM (m-ADM) in (a) depressive relapse prevention, (b) key secondary outcomes, and (c) cost effectiveness. The study design was a parallel 2-group randomized controlled trial comparing those on m-ADM (N = 62) with those receiving MBCT plus support to taper/discontinue antidepressants (N = 61). Relapse/recurrence rates over 15-month follow-ups in MBCT were 47%, compared with 60% in the m-ADM group (hazard ratio = 0.63; 95% confidence interval: 0.39 to 1.04). MBCT was more effective than m-ADM in reducing residual depressive symptoms and psychiatric comorbidity and in improving quality of life in the physical and psychological domains. There was no difference in average annual cost between the 2 groups. Rates of ADM usage in the MBCT group was significantly reduced, and 46 patients (75%) completely discontinued their ADM. For patients treated with ADM, MBCT may provide an alternative approach for relapse prevention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conceptualising Social Housing within the Wider Housing Market: A Vacancy Chain Model

There have been increasing calls for studies of housing systems that are more integrative and pluralistic in nature. Understanding the relationship of social housing systems to the wider housing market remains a key challenge. The mobility of households and the structural configuration of supply are both of importance, demanding methods able to reconcile both. This paper propounds vacancy chain models as offering significant potential in this regard, allowing policy analysis and options appraisal to be built on more dynamic conceptualisations of housing systems. The theoretical basis for vacancy chain models is developed before an account is given of a model developed of the Bradford (UK) social rented sector. The results suggest that social renting is very closely linked to the wider housing market and consequently the impacts of policy and investment may be felt beyond the sector. Observations on the future development of vacancy chain models are offered.     

New edible coatings composed of galactomannans and collagen blends to improve the postharvest quality of fruits – Influence on fruits gas transfer rate

The objective of this work was to produce new edible coatings, based on a mixture of galactomannans from novel sources (seeds of Adenanthera pavonina and Caesalpinia pulcherrima), collagen and glycerol, and to determine their influence in gas transfer rates when they are applied on mangoes and apples. The first part of the work consisted in obtaining coating solutions with the convenient values of wettability for each fruit; such coating solutions were then characterized in terms of their permeability (to CO₂, O₂ and water vapour), mechanical properties, colour and opacity. Gas transfer rates from mangoes coated with a solution of A. pavonina galactomannan (0.5%), collagen (1.5%) and glycerol (1.5%) were compared with those of mangoes without coating: 28% less O₂ consumption and 11% less CO₂ production were observed in coated mangoes. The same procedure was performed in apples (in this case using C. pulcherrima galactomannan (0.5%), collagen (1.5%) and no glycerol); the CO₂ production and the O₂ consumption was approximately 50% lower in apples with coating than in apples without coating. The results suggest that these coatings can reduce gas transfer rates in these fruits, and can be therefore important tools to extend their shelf life.