HOW TO FIND A STONE CRAYFISH AUSTROPOTAMOBIUS TORRENTIUM (SCHRANK, 1803): A BIOGEOGRAPHIC STUDY IN EUROPE

The stone crayfish Austropotamobius torrentium (Schrank, 1803) is widely distributed in Southeastern and Central Europe. However, this information has not been verified until recently because of: • ignorance about biogeographic notion and hydrography and • ignorance of data in the literature. Overcoming these problems during the last decade, the distribution pattern of the stone crayfish has now become apparent in Europe. It is known from Luxembourg and Germany to the west, from Turkey to the east, from Germany and the Czech Republic to the north and from Greece to the south. It is absent in the northeastern part of the Pannonian basin as well as in Poland and Ukraine. Its presence in Luxembourg and the Czech Republic may be related not to natural distribution but to introduction by humans through history. The discovery of the stone crayfish in Italy and Turkey as well as its re-discovery in France during the 1990s proves the biogeographic conception that this animal belongs to the Danubian fauna. It probably originates from the southwestern part of the Pannonian basin

Freshwater crayfish in South Tyrol (Italy): Distribution and protection measures of endangered Austropotamobius pallipes

Freshwater crayfish are among the most endangered animals in Europe. Information on freshwater crayfish in the Italian province of South Tyrol was insufficient until the recent studies on their historical and present distribution, which showed the alarming facts that only 15 standing and running waters remained as freshwater crayfish habitats, carrying the native Austropotamobius pallipes and the allochthonous Astacus astacus, Orconectes limosus, and Pacifastacus leniusculus. Still ongoing alterations or degradation of water bodies have contributed to the high degree of population decline and loss. While the exotic crayfish O. limosus and P. leniusculus could develop higher densities, most of the autochthonous A. pallipes populations were weak and consisted only of a few individuals. Three populations of A. pallipes, however, remained in a good condition, representing potential sources for recovery programs. Protection measures currently carried out in South Tyrol involve breeding, restocking and reintroduction of autochthonous A. pallipes individuals in ecological intact water bodies

Microhabitat use by the white-clawed crayfish in a Tuscan stream.

Habitat modification, pollution, overfishing, poaching, competition from nonindigenous species, and diseases have led to the extinction in Europe of many populations of indigenous crayfish. Under the rationale that any programme of reintroduction should be preceded by a thorough understanding of habitat requirements of the species of concern, we studied the microhabitat use of an Austropotamobius pallipes population in Tuscany, central Italy. Microhabitat use was assessed for water depth, current velocity, substrate, percentages of boulders, underwater tree roots, and in-stream vegetation cover. Results show that A. pallipes’ habitat use is size-partitioned. Smaller individuals mostly occupy stream edges in shallow waters with submerged roots, whereas larger individuals use deeper waters, often associated with boulders. Crayfish spatial distribution is restricted mostly to the microhabitats characterised by extensive cover and slow current velocity. The study highlights the importance of habitat heterogeneity and cover elements for the protection of this indigenous species

The activity of signal crayfish (Pacifastacus leniusculus) in relation to thermal and hydraulic dynamics of an alluvial stream, UK

Signal crayfish (Pacifastacus leniusculus) are an invasive species of global significance because of their detrimental impacts on freshwater environments and native organisms. The movement of signal crayfish was continuously monitored for 150-days through a 20-m reach of an alluvial stream in the UK. Passive integrated transponder-tags were attached to crayfish, allowing their location to be monitored relative to 16 antennae which were buried beneath the river bed. The activity of crayfish was related to water depth and temperature, which were continuously monitored within the instrumented reach. Crayfish were highly nocturnal, with less than 6% of movements recorded during daylight hours. Activity declined from September and was minimal in November when water temperature was low and flow depth was high. However, relations between environmental parameters and crayfish activity had poor explanatory power which may partly reflect biological processes not accounted for in this study. Water depth and temperature had a limiting relationship with crayfish activity, quantified using quantile regression. The results extend existing data on signal crayfish nocturnalism and demonstrate that, although signal crayfish can tolerate a range of flows, activity becomes limited as water temperature declines seasonally and when water depth remains high in autumn and winter months

Interdisciplinarity to reconstruct historical introductions: solving the status of cryptogenic crayfish

Anciently introduced species can be confounded with native species because introduction pre-dates the first species inventories or because of the loss of the collective memory of the introductions. The term ‘cryptogenic species’ denotes species of unknown or unclear status (native versus non-native) in a given territory, and disciplinary approaches are often insufficient for solving their true status. Here, we follow an integrative, multidisciplinary approach to solve the status of a cryptogenic species, proposing that building on evidence from multiple disciplines can produce robust and clarifying insights. We undertook an exhaustive review of information on a putatively native crayfish (Austropotamobius italicus) in Spain. The reviewed information included taxonomy, genetics and phylogeography, history, archaeology, linguistics, biogeography, ecology, symbiotic organisms and even gastronomy and pharmacy. The knowledge produced by different scientific disciplines converges to indicate that A. italicus is a non-native species in Spain. Historical documents even identify the first introduction event: crayfish were shipped from Italy to Spain in 1588 as a diplomatic gift from Francesco I de' Medici to King Philip II of Spain. Previous discussions on the status of A. italicus focussed on inconclusive and often confusing genetic results and excluded the rich and clarifying evidence available from other approaches and disciplines. Interdisciplinarity is an often-invoked but rarely implemented practice in an academic environment that increasingly promotes narrow-focussed specialization. Our review shows that the integration of disciplines can surpass disciplinary approaches in solving scientific controversies. Our results have straightforward implications for strategies to conserve biological diversity in Spain and Europe, urging a debate on the appropriateness of devoting conservation efforts to non-native species.Peer Reviewe

Development of a new assessment tool for cervical myelopathy using hand-tracking sensor: Part 2: normative values

Purpose To set a baseline measurement of the number of hand flexion–extension cycles and analyse the degree of motion in young healthy individuals, measured by leap motion controller (LMC), besides describing gender and dominant hand differences. Methods Fifty healthy participants were asked to fully grip-and-release their dominant hand as rapidly as possible for a maximum of 3 min or until subjects fatigued, while wearing a non-metal wrist splint. Participants also performed a 15-s grip-and-release test. An assessor blindly counted the frequency of grip-and-release cycles and magnitude of motion from the LMC data. Results The mean number of the 15-s G–R cycles recorded by LMC was: 47.7 ± 6.5 (test 1, LMC); and 50.2 ± 6.5 (test 2, LMC). In the 3-min test, the total number of hand flexion–extension cycles and the degree of motion decreased as the person fatigued. However, the decline in frequency preceded that of motion’s magnitude. The mean frequency of cycles per 10-s interval decreased from 35.4 to 26.6 over the 3 min. Participants reached fatigue from 59.38 s; 43 participants were able to complete the 3-min test. Conclusions Normative values of the frequency of cycles and extent of motion for young healthy individuals, aged 18–35 years, are provided. Future work is needed to establish values in a wider age range and in a clinical setting

Polymeric human Fc-fusion proteins with modified effector functions

The success of Fc-fusion bio-therapeutics has spurred the development of other Fc-fusion products for treating and/or vaccinating against a range of diseases. We describe a method to modulate their function by converting them into well-defined stable polymers. This strategy resulted in cylindrical hexameric structures revealed by tapping mode atomic force microscopy (AFM). Polymeric Fc-fusions were significantly less immunogenic than their dimeric or monomeric counterparts, a result partly owing to their reduced ability to interact with critical Fc-receptors. However, in the absence of the fusion partner, polymeric IgG1-Fc molecules were capable of binding selectively to FcγRs, with significantly increased affinity owing to their increased valency, suggesting that these reagents may prove of immediate utility in the development of well-defined replacements for intravenous immunoglobulin (IVIG) therapy. Overall, these findings establish an effective IgG Fc-fusion based polymeric platform with which the therapeutic and vaccination applications of Fc-fusion immune-complexes can now be explored

Engineered hexavalent Fc proteins with enhanced Fc-gamma receptor avidity provide insights into immune-complex interactions

Tania Rowley et al. present multivalent Fc molecules with enhanced avidity for Fc gamma receptors in order to improve the treatment of autoantibody-mediated human diseases. They found several key amino acids involved in Fc receptor binding interactions