A novel biphasic extractive membrane bioreactor for minimization of membrane-attached biofilms

Extractive membrane bioreactor (EMB) systems offer a means of biologically treating wastewaters, but, like other membrane processes, are constrained by their tendency to be fouled by membrane-attached biofilms (MABs). This study describes a new approach to eradicate MAB formation and accumulation in EMB systems. To this end, an innovative EMB configuration, the biphasic extractive membrane bioreactor (BEMB), has been developed. In BEMB systems, the two main constituents of the EMB process, membrane and bacteria, are kept separated and interact via a suitable recirculating solvent. Nineteen candidate solvents were tested to assess their suitability for BEMB application. Based on the results of the solvent selection, guidelines are provided to screen solvents for BEMB application. BEMB and EMB runs were carried out to demonstrate the effectiveness of BEMB technology in avoiding MAB accumulation and to compare BEMB and EMB performance. A synthetic wastewater containing monochlorobenzene (MCB) was used as a model system. Abiotic BEMB and EMB runs were carried out and used as comparative references for estimating the effect of MAB accumulation on system performance. MAB thickness in the BEMB systems was controlled at 18 microm during 1 month of operation, whereas, in the EMB systems, MAB thickness reached 1250 microm. Analysis of mass transport in EMB and BEMB systems revealed that the high affinity of the permeating molecules for the solvent may contribute to a reduction in shell-side mass transfer resistance. This reduction of shell-side mass transfer resistance and the absence of MAB accumulation led to overall mass transfer coefficients of about sevenfold greater (4.5 x 10(-5) m s(-1)) in the BEMB system than in the EMB system (0.6 x 10(-5) m s(-1)).     

薰衣草高质量DNA提取及ISSR-PCR多重化体系的建立

以伊犁薰衣草‘701’新鲜叶片为材料,对4种基因组DNA提取方法进行比较,并通过单因子梯度比较试验结合L9(34)正交优化设计,对ISSR-PCR扩增体系中退火温度、DNA、Mg2+、dNTP和引物浓度进行最佳条件及配比筛选。结果表明,改良3×CTAB法是薰衣草高质量DNA少量提取的最佳方法 ;建立薰衣草ISSR-PCR扩增优化体系为,20μL反应体系中包括模板DNA 50 ng,Mg2+3 mmol/L,dNTP 0.3 mmol/L,引物0.3 mmol/L,Taq酶1 U;扩增程序退火温度为56℃。运用本试验建立的ISSR-PCR优化体系,对5份薰衣草种质进行了初步验证,获得了良好的多样性扩增条带。     

In situ product recovery of n-butanol using polymeric resins

Polymeric resins with high n-butanol adsorption affinities were identified from a candidate pool of commercially available materials representing a wide array of physical and chemical properties. Resin hydrophobicity, which was dictated by the chemical structure of its constituent monomer units, most greatly influenced the resin-aqueous equilibrium partitioning of n-butanol whereas ionic functionalization appeared to have no effect. In general, those materials derived from poly(styrene-co-divinylbenzene) possessed the greatest n-butanol affinity, while the adsorption potential of these resins was limited by their specific surface area. Resins were tested for their ability to serve as effective in situ product recovery (ISPR) devices in the n-butanol fermentation by Clostridium acetobutylicum ATCC 824. In small-scale batch fermentations, the addition of 0.05 kg/L Dowex Optipore SD-2 facilitated achievement of effective n-butanol titers as high as 2.22% (w/v), well above the inhibitory threshold of C. acetobutylicum ATCC 824, and nearly twice that of traditional, single-phase fermentations. Retrieval of n-butanol from resins via thermal treatment was demonstrated with high efficiency and predicted to be economically favorable. Due to its modular nature, the proposed ISPR design exhibits strong potential for compatibility with future n-butanol fermentation efforts.     

L’industrie lithique des gisements du Pléistocène inférieur de Barranco León et Fuente Nueva 3 à Orce, Grenade, Espagne

The archaeological localities of Barranco León and Fuente Nueva 3 in Orce, Grenade, in actuality have the oldest lithic artifacts in Europe; they are the oldest evidence of human occupation in the east of Europe. When compared the results from faunal analysis and magnetostratigraphical study, notably through the presence of Allophaiomys lavocati allow for a date of around 1.3 Ma. The raw material used for developing these lithic industries are, basically limestone or siliceous rocks, these raw materials selected were smoothed down in situ. The techniques used are knapping at raised with a hammerstone, and we can find all the different elements of the “chaine opératoire”. Both localities are characterised by the predominance of flakes and debris, cores, and some knapped cobbles sowing mediocre aspect. The technical and typological features of both lithic assemblages have an opportunist character but they are relatively sophisticated too.     

Alleviating monoterpene toxicity using a two-phase extractive fermentation for the bioproduction of jet fuel mixtures in Saccharomyces cerevisiae

Monoterpenes are a diverse class of compounds with applications as flavors and fragrances, pharmaceuticals and more recently, jet fuels. Engineering biosynthetic pathways for monoterpene production in microbial hosts has received increasing attention. However, monoterpenes are highly toxic to many microorganisms including Saccharomyces cerevisiae, a widely used industrial biocatalyst. In this work, the minimum inhibitory concentration (MIC) for S. cerevisiae was determined for five monoterpenes: β‐pinene, limonene, myrcene, γ‐terpinene, and terpinolene (1.52, 0.44, 2.12, 0.70, 0.53 mM, respectively). Given the low MIC for all compounds tested, a liquid two‐phase solvent extraction system to alleviate toxicity during fermentation was evaluated. Ten solvents were tested for biocompatibility, monoterpene distribution, phase separation, and price. The solvents dioctyl phthalate, dibutyl phthalate, isopropyl myristate, and farnesene showed greater than 100‐fold increase in the MIC compared to the monoterpenes in a solvent‐free system. In particular, the MIC for limonene in dibutyl phthalate showed a 702‐fold (308 mM, 42.1 g L^?1 of limonene) improvement while cell viability was maintained above 90%, demonstrating that extractive fermentation is a suitable tool for the reduction of monoterpene toxicity. Finally, we estimated that a limonane to farnesane ratio of 1:9 has physicochemical properties similar to traditional Jet‐A aviation fuel. Since farnesene is currently produced in S. cerevisiae, its use as a co‐product and extractant for microbial terpene‐based jet fuel production in a two‐phase system offers an attractive bioprocessing option. Biotechnol. Bioeng. 2012; 109: 2513–2522. © 2012 Wiley Periodicals, Inc.     

Oldowayen archaïque et Oldowayen classique de l’Afrique à l’Europe méditerranéenne

Analyzing lithic industries of Lower Pleistocene and beginning of Middle Pleistocene times allows to define three groups not clearly chronological but which reflect the cognitive evolution of prehistoric Men who knapped them and the constraints of the environment: - “Archaic Oldowan” industries in which raw flakes are dominant and no small tools retouched on flakes or debris are present; - “Classical Oldowan” industries in which raw flakes are dominant and small tools retouched on flakes and debris – especially scrapers – are present; - “Acheulean industries”, in which bifaces are present – generally in small proportions – and small retouched tools are increasingly standardized.     

Prospects for conserving biodiversity in Amazonian extractive reserves

Non‐timber forest product (NTFP) extraction is a popular alternative to timber extraction that figures prominently in efforts to utilize tropical forests sustainably. But the ability to conserve biodiversity through NTFP management, particularly in extractive reserves in Amazonia, has remained untested. We found that intensive management of Euterpe oleracea (Palmae) fruit, one of the most important extractive products in the Amazon, has substantial impacts on biodiversity, whereas moderate management does not. We mimicked traditional levels of fruit harvest in a replicated experiment over one fruiting season. High‐intensity harvest (75% of fruits removed) reduced avian frugivore species diversity by 22%. Low‐intensity harvest (40% of fruits removed), however, had no effect on diversity. On a larger scale, we found that forests with enriched densities of E. oleracea supported more fruit‐eating birds but fewer non fruit‐eating birds than non‐enriched forests. Taken together, these results suggest that intensive NTFP management to meet market demands may trigger substantial ecological impacts, at least at the level of our study. E. oleracea harvest should be limited where conservation of biodiversity is a goal.     

The conditions for tool use in primates: implications for the evolution of material culture

In order to identify the conditions that favored the flourishing of primate tool use into hominid technology, we examine inter- and intraspecific variation in manufacture and use of tools in extant nonhuman primates, and develop a model to account for their distribution. We focus on tools used in acquiring food, usually by extraction. Any model for the evolution of the use of feeding tools must explain why tool use is found in only a small subset of primate species, why many of these species use tools much more readily in captivity, why routine reliance on feeding tools is found in only two species of ape, and why there is strong geographic variation within these two species. Because ecological factors alone cannot explain the distribution of tool use in the wild, we develop a model that focuses on social and cognitive factors affecting the invention and transmission of tool-using skills. The model posits that tool use in the wild depends on suitable ecological niches (especially extractive foraging) and the manipulative skills that go with them, a measure of intelligence that enables rapid acquisition of complex skills (through both invention and, more importantly, observational learning), and social tolerance in a gregarious setting (which facilitates both invention and transmission). The manipulative skills component explains the distribution across species of the use of feeding tools, intelligence explains why in the wild only apes are known to make and use feeding tools routinely, and social tolerance explains variation across populations of chimpanzees and orangutans. We conclude that strong mutual tolerance was a key factor in the explosive increase in technology among hominids, probably intricately tied to a lifestyle involving food sharing and tool-based processing or the acquisition of large, shareable food packages.     

Identification of Quina and Vasconian technocomplexes in Gatzarria Cave (north-western Pyrenees), based on the stratigraphic,taphonomic and technological revision of the Georges Laplace collections

The archaeo-sequence of Gatzarria Cave (Ossas-Suhare, Pyrénées-Atlantiques, France), in the northwestern foothills of the Pyrenees, records several phases of the Middle Palaeolithic and the initial stages of the Upper Palaeolithic. This type of deposit in a karstic context enables us to characterize diachronic changes in industries and to demonstrate the relative preservation of the assemblages. This cavity was excavated by Georges Laplace between 1951 and 1976 and contains a complex stratigraphy that was exposed to significant post-depositional processes. It was thus essential to test that the archaeological levels were intact before any techno-economic analysis. Several recent studies have questioned the homogeneity of the archaeological remains in the back of the cave. This article focuses on the sequencing of the industries attributed to the Quina and the Vasconian, based on the correlation of different types of taphonomic and typo-technological analyses (density of remains, surface conditions, refits, spatial distribution, analysis of the fieldwork notebooks). Ultimately, this work sheds light on the sequencing of lithic technocomplexes at a macro-regional scale in a relatively poorly-documented key zone between northern Aquitaine and the Cantabrian mountains.     

Tool Use by Chimpanzees at Ngogo,Kibale National Park,Uganda

Chimpanzees make and use a wide variety of tools in the wild. The size and composition of their toolkits vary considerably among populations and at least to some extent within them. Chimpanzees at several well documented sites mostly use tools in extractive foraging, and extractive tool use can substantially increase their foraging efficiency. They also use tools for hygiene and for several other purposes, including attracting the attention of conspecifics, as in leaf-clipping. Some of the interpopulation variation in toolkits results from ecological variation, but differences in the efficiency of social transmission, perhaps related to differences in social tolerance, presumably also contribute. I describe tool use by chimpanzees in an unusually large community at Ngogo, in Kibale National Park, Uganda. Researchers have described some tool use for the community previously, but this is the most extensive report and is based on observations over 11 yr. The Ngogo chimpanzees have a small toolkit and use tools rarely except in leaf-clipping displays and to clean body surfaces; notably, males often use leaf napkins to wipe their penes after copulation. Extractive tool use is rare and is limited mostly to leaf-sponging and, less often, honey-fishing. Social tolerance is not low at Ngogo, but use of tools for extractive foraging, in ways documented at other field sites, may have little potential to increase foraging efficiency. Future research will undoubtedly show more tool use by females, which were underrepresented in my observations, but will probably not document much increase in the toolkit or in the use of extractive tools.