A restatement of recent advances in the natural science evidence base concerning neonicotinoid insecticides and insect pollinators

A summary is provided of recent advances in the natural science evidence base concerning the effects of neonicotinoid insecticides on insect pollinators in a format (a ‘restatement'') intended to be accessible to informed but not expert policymakers and stakeholders. Important new studies have been published since our recent review of this field (Godfray et al. 2014 Proc. R. Soc. B 281, 20140558. (doi:10.1098/rspb.2014.0558)) and the subject continues to be an area of very active research and high policy relevance.     

利用絮凝进行微藻采收的研究进展

微藻可生产不饱和脂肪酸及色素等多种高附加值产品,同时也可用来生产可再生清洁能源如生物柴油等,具有良好的应用前景。但是,目前微藻细胞的采收成本高居不下,已成为限制微藻生物技术大规模应用的重要因素之一。与其他方法相比,絮凝采收成本低、操作简便,是很有应用前景的采收方法。本文综述了国内外利用化学絮凝、物理絮凝及生物絮凝等方法对不同微藻细胞进行采收的研究,重点对生物絮凝方法进行了总结。利用微生物絮凝剂及微藻细胞的自絮凝进行微藻生物量的回收,是微藻采收技术中环境友好、低成本和行之有效的新方法之一。     

A narrowing gyre? The Lega Nord and the shifting balance of Italian immigration policy

This article reflects on the relations between xenophobic parties and immigration policy in Italy. It argues that the salience of the Northern League (Lega Nord), the instability of the Italian party system and the recent transformation of Italy from an emigration country to an immigration country all contribute to Italy's difficulty in achieving a coherent immigration policy. Since the first comprehensive immigration policy emerged in 1998 with the Turco-Napolitano law, there have been six changes of government, with frequent oscillation between centre-right and centre-left coalitions. While the effects of these oscillations, particularly of the centre-right's effort to restrict immigrants’ rights and entry possibilities, have been dampened by the Italian courts and the European Union, it is still problematic to speak of an Italian model. Drawing on Carvalho's book, this article will address the effects of the Lega on creating and maintaining this policy imbalance.     

Spatial and temporal variation in harvest probabilities for American black duck

Assessing spatial variation in waterfowl harvest probabilities from banding data is challenging because reporting and recovery probabilities have distinct spatial patterns that covary temporally with harvesting regulations, hunter effort, and reporting methods. We analyzed direct band recovery data from American black ducks banded on the Canadian breeding grounds from 1970 through 2010. Data were registered to a 1‐degree grid and analyzed using hierarchical logistic regression models with spatially correlated errors to estimate the annual probabilities of band recovery and the proportion of individuals recovered in Canada. Probability of harvest was estimated from these values, in combination with independent estimates of reporting probabilities in Canada and the USA. Model covariates included estimates of hunting effort and factors for harvest regulation and band reporting methods. Both the band recovery processes and the proportion of individuals recovered in Canada had significant spatial structure. Recovery probabilities were highest in southern Ontario, along the Saint Lawrence River in Quebec, and in Nova Scotia. Black ducks breeding in Nova Scotia and southern Quebec were harvested predominantly in Canada. Recovery probabilities for juveniles were correlated with hunter effort, while the adult recoveries were weakly correlated with the implementation of stricter harvest regulations in the early 1980s. Mean harvest probability decreased in the northern portion of the survey area but remained stable or even increased in the south. Harvest probabilities for juveniles in 2010 exceeded 20% in southern Quebec and the Atlantic provinces. Our results demonstrate fine‐scale variation in harvest probabilities for black duck on the Canadian breeding ground. In particular, harvest probabilities should be closely monitored along the Saint Lawrence River system and in the Atlantic provinces to avoid overexploitation.     

Long‐term livestock exclusion facilitates native woody plant encroachment in a sandy semiarid rangeland

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PDADMAC flocculation of Chinese hamster ovary cells: Enabling a centrifuge-less harvest process for monoclonal antibodies

High titer (>10 g/L) monoclonal antibody (mAb) cell culture processes are typically achieved by maintaining high viable cell densities over longer culture durations. A corresponding increase in the solids and sub-micron cellular debris particle levels are also observed. This higher burden of solids (≥15%) and sub-micron particles typically exceeds the capabilities of a continuous centrifuge to effectively remove the solids without a substantial loss of product and/or the capacity of the harvest filtration train (depth filter followed by membrane filter) used to clarify the centrate. We discuss here the use of a novel and simple two-polymer flocculation method used to harvest mAb from high cell mass cell culture processes. The addition of the polycationic polymer, poly diallyldimethylammonium chloride (PDADMAC) to the cell culture broth flocculates negatively-charged cells and cellular debris via an ionic interaction mechanism. Incorporation of a non-ionic polymer such as polyethylene glycol (PEG) into the PDADMAC flocculation results in larger flocculated particles with faster settling rate compared to PDADMAC-only flocculation. PDADMAC also flocculates the negatively-charged sub-micron particles to produce a feed stream with a significantly higher harvest filter train throughput compared to a typical centrifuged harvest feed stream. Cell culture process variability such as lactate production, cellular debris and cellular densities were investigated to determine the effect on flocculation. Since PDADMAC is cytotoxic, purification process clearance and toxicity assessment were performed.     

Cost modelling of Pseudomonas fluorescens and Pseudomonas chlororaphis as biocontrol for competitive exclusion of Salmonella enterica on tomatoes

Published research on process-based models for biocontrol of foodborne pathogens on produce is limited. The aim of this research was to develop cost model estimates for competitive exclusion (CE) process using Pseudomonas fluorescens and Pseudomonas chlororaphis (non-plant pathogenic and non-human pathogen) as biocontrol against Salmonella enterica on tomatoes. Cost estimates were based on material inputs, equipment, facilities, and projected processing conditions of post-harvest packaging of tomatoes. The microbiological data for inactivation of S. enterica was based on published papers. The small-scale processing facility was assumed to have a processing capacity of 2000 kg of tomatoes/hour for 16 h per day, operational 6 days a week, and for 3-months /year. The large-scale facility was assumed to have a processing capacity of 100,000 kg of tomatoes/hour. Estimated initial capital investment costs for small and large-scale models (production facility) were US$391,000 and US$2.1 million. Application of CE for biocontrol of S. enterica on tomatoes was estimated at US$0.0058–0.073/kg of tomatoes during commercial processing operations. This exceeds chlorine wash technology estimated at US$0.00046/kg and is competitive with gaseous chlorine dioxide at US$0.02–0.21/kg. For high-value produce, CE may complement existing technologies increase food safety, reduce storage loses, and extend shelf life of produce.     

Environmental Risk Management Decision-Making in a Societal Context

Recent studies point to the need for improved understanding of environmental management frameworks designed to combine qualitative public and quantitative technical inputs in decision-making processes. Flux in public perception and concern about risks imply frameworks must be iterative in nature and incorporate a variety of assessment triggers in the form of decision points. A conceptual model is proposed here to explain the de facto operation of standard risk analytic frameworks within the broader sociopolitical milieu of public policy. The model is presented as a decision flow diagram that emphasizes setting environmental management goals based on societal input and the formulation of decision criteria for selecting management actions to achieve those goals. Prospective and retrospective decision control points operate to select management options that, respectively, avoid or reduce actual or predicted effects. Feedback loops that modify risk management outcomes are identified. Technical and scientific inputs (i.e., risk analysis) are assigned an essential information role within the framework and are responsible for informing the management process with the results of appropriately conducted and reviewed investigations. The proposed model is intended primarily to indicate how environmental risk management decision-making and associated technical assessments may be influenced by social pressures. It is hoped this understanding will lead to analytical transparency and better public communication of the environmental implications of policy options.