A plea for scale, and why it matters for invasive species management, biodiversity and conservation

Invasive species are suspected to be major contributors to biodiversity declines worldwide. Counterintuitively, however, invasive species effects are likely scale dependent and are hypothesized to be positively related to biodiversity at large spatial scales. Past studies investigating the effect of invasion on biodiversity have been mostly conducted at small scales (\u3c100 m2) that cannot represent large dynamic landscapes by design. Therefore, replicated experimental evidence supporting a negative effect of invasive plants on biodiversity is lacking across many landscape types, including large grasslands. We collected data across eight large (333–809 ha) grassland landscapes managed with pyric herbivory—that is the recoupling of fire and grazing—to test how an invasive legume Lespedeza cuneata affected plant and bird communities at spatial grains ranging from 0.1 m2 to \u3e3,000,000 m2. Lespedeza cuneata invasion effects on grassland plant diversity and composition changed with scale, being negative at small spatial grains (0.1 m2) and neutral or positive at large spatial grains (\u3e3,000,000 m2). Lespedeza cuneata abundance did not significantly affect bird diversity at any spatial grain measured. Lespedeza cuneata may negatively affect biodiversity if abundances are greater than those observed in this study. However, previous research suggests that Lespedeza cuneata may not be capable of exceeding 20% canopy cover across large landscapes (\u3e400 ha). Control and eradication strategies can be costly and are fraught with risk. If data do not clearly support a negative Lespedeza cuneata abundance–biodiversity relationship, and if invasion is spatially limited across large landscapes, ongoing control and eradication efforts may be unwarranted and ineffective. Synthesis and applications: Invasive species effects gleaned from small-scale studies may not reliably predict their effects at larger scales. Although we recognize the importance of small-scale studies in potentially isolating individual mechanisms, management strategies based solely on results from small-scale studies of invasion are unlikely to increase or conserve biodiversity across large landscapes. Rather, processes that generate landscape heterogeneity—like pyric herbivory—are probably more important for promoting biodiversity across all scales. Scale is a central problem in ecology, and defining scale in management objectives is essential for effective biodiversity conservation

Immune-Complex Mimics as a Molecular Platform for Adjuvant-Free Vaccine Delivery

Protein-based vaccine development faces the difficult challenge of finding robust yet non-toxic adjuvants suitable for humans. Here, using a molecular engineering approach, we have developed a molecular platform for generating self-adjuvanting immunogens that do not depend on exogenous adjuvants for induction of immune responses. These are based on the concept of Immune Complex Mimics (ICM), structures that are formed between an oligomeric antigen and a monoclonal antibody (mAb) to that antigen. In this way, the roles of antigens and antibodies within the structure of immune complexes are reversed, so that a single monoclonal antibody, rather than polyclonal sera or expensive mAb cocktails can be used. We tested this approach in the context of Mycobacterium tuberculosis (MTB) infection by linking the highly immunogenic and potentially protective Ag85B with the oligomeric Acr (alpha crystallin, HspX) antigen. When combined with an anti-Acr monoclonal antibody, the fusion protein formed ICM which bound to C1q component of the complement system and were readily taken up by antigen-presenting cells in vitro. ICM induced a strong Th1/Th2 mixed type antibody response, which was comparable to cholera toxin adjuvanted antigen, but only moderate levels of T cell proliferation and IFN-γ secretion. Unfortunately, the systemic administration of ICM did not confer statistically significant protection against intranasal MTB challenge, although a small BCG-boosting effect was observed. We conclude that ICM are capable of inducing strong humoral responses to incorporated antigens and may be a suitable vaccination approach for pathogens other than MTB, where antibody-based immunity may play a more protective role

Injury rates and injury risk factors among federal bureau of investigation new agent trainees

<p>Abstract</p> <p>Background</p> <p>A one-year prospective examination of injury rates and injury risk factors was conducted in Federal Bureau of Investigation (FBI) new agent training.</p> <p>Methods</p> <p>Injury incidents were obtained from medical records and injury compensation forms. Potential injury risk factors were acquired from a lifestyle questionnaire and existing data at the FBI Academy.</p> <p>Results</p> <p>A total of 426 men and 105 women participated in the project. Thirty-five percent of men and 42% of women experienced one or more injuries during training. The injury incidence rate was 2.5 and 3.2 injuries/1,000 person-days for men and women, respectively (risk ratio (women/men) = 1.3, 95% confidence interval = 0.9-1.7). The activities most commonly associated with injuries (% of total) were defensive tactics training (58%), physical fitness training (20%), physical fitness testing (5%), and firearms training (3%). Among the men, higher injury risk was associated with older age, slower 300-meter sprint time, slower 1.5-mile run time, lower total points on the physical fitness test (PFT), lower self-rated physical activity, lower frequency of aerobic exercise, a prior upper or lower limb injury, and prior foot or knee pain that limited activity. Among the women higher injury risk was associated with slower 300-meter sprint time, slower 1.5-mile run time, lower total points on the PFT, and prior back pain that limited activity.</p> <p>Conclusion</p> <p>The results of this investigation supported those of a previous retrospective investigation emphasizing that lower fitness and self-reported pain limiting activity were associated with higher injury risk among FBI new agents.</p

The physiological significance of putative diuretic factors in the yellow fever mosquito, Aedes aegypti

The post blood meal diuresis in the mosquito may be regulated by neuroendocrine factors. Two families of neuropeptides, the diuresins and the leucokinins stimulate fluid secretion in Malpighian tubules of several insects. Recently, several new peptides have been isolated and synthesized from both families of neuropeptides. A putative diuresin-like diuretic factor has been purified and sequenced from Culex salinarius. Several leucokinins have been isolated from two species of mosquitoes, the culekinin depolarizing peptides (CDP-I, II and III) isolated from C. salinarius and Aedes leucokinin peptides (ALP-I, II and III) isolated from Aedes aegypti. The three major objectives of this work were: (1) to examine the effect of 5-hydroxytryptamine (5-HT), the mosquito diuresin and the mosquito leucokinins on urine production in vivo in the mosquito A. aegypti, (2) to inhibit the biological effects of ALP-I and C. salinarius diuresin with antibodies raised against these peptides, (3) to determine if biologically active peptides increased Malpighian tubule intracellular second messengers 3',5'-cyclic adenosine monophosphate (cAMP) and or inositol 1,4,5-trisphosphate (IP3 This study has demonstrated that putative diuretic factors from two families of insect neuropeptides and 5-HT influence Malpighian tubule function. The mosquito diuresin, leucokinins and 5-HT stimulated total urine production in a dose dependent manner. A significant inhibition of peptide-stimulated urine production occurred following immunization with either ALP-I or C. salinarius diuresin antibodies. The C. salinarius diuresin significantly (p 0.05) increased intracellular cAMP concentrations in A. aegypti tubules. Stimulation of A. aegypti tubules with either CDP-II or 5-HT resulted in significant increases in both intracellular cAMP and IP3 concentrations. All of the mosquito leucokinins, with the exception of CDP-I, significantly increased intracellular IP3 in tubules. Data presented here suggest that the mosquito leucokinins may function on the Malpighian tubules of A. aegypti by increasing intracellular Ca²⁺ through the release of IP3 sensitive intracellular Ca²⁺ stores

Generalist bird exhibits site-dependent resource selection

Quantifying resource selection (an organism\u27s disproportionate use of available resources) is essential to infer habitat requirements of a species, develop management recommendations, predict species responses to changing conditions, and improve our understanding of the processes that underlie ecological patterns. Because study sites, even within the same region, can differ in both the amount and the arrangement of cover types, our objective was to determine whether proximal sites can yield markedly different resource selection results for a generalist bird, northern bobwhite (Colinus virginianus). We used 5 years of telemetry locations and newly developed land cover data at two, geographically distinct but relatively close sites in the south-central semi-arid prairies of North America. We fit a series of generalized linear mixed models and used an information-theoretic model comparison approach to identify and compare resource selection patterns at each site. We determined that the importance of different cover types to northern bobwhite is site-dependent on relatively similar and nearby sites. Specifically, whether bobwhite selected for shrub cover and whether they strongly avoided trees, depended on the study site in focus. Additionally, the spatial scale of selection was nearly an order of magnitude different between the cover types. Our study demonstrates that—even for one of the most intensively studied species in the world—we may oversimplify resource selection by using a single study site approach. Managing the trade-offs between practical, generalized conclusions and precise but complex conclusions is one of the central challenges in applied ecology. However, we caution against setting recommendations for broad extents based on information gathered at small extents, even for a generalist species at adjacent sites. Before extrapolating information to areas beyond the data collected, managers should account for local differences in the availability, arrangement, and scaling of resources

Role of microRNA-132 in Opioid Addiction through Modification of Neural Stem Cell Differentiation

In this editorial, we focused on the article, &ldquo;MicroRNA-132 in the Adult Dentate Gyrus is Involved in Opioid Addiction Via Modifying the Differentiation of Neural Stem Cells&rdquo; by Jia and colleagues [...