Characterisation of bird cherry-oat aphid (Rhopalosiphum padi L.) behaviour and aphid host preference in relation to partially resistant and susceptible wheat landraces.

The bird cherry-oat aphid (Rhopalosiphum padi L.) is a major pest of wheat (Triticum aestivum L.) and can cause up to 30% yield losses. Heritable plant resistance to aphids is both an economically and ecologically sound method for managing aphids. Here we report how the behaviour and performance of R. padi differs on two resistant, one susceptible wheat landrace and a susceptible elite wheat variety. Feeding behaviour differed among the genotypes, with aphids on resistant lines spending longer in the pathway phase and less time phloem feeding. These behaviours suggest that both inter- and intracellular factors encountered during pathway and phloem feeding phases could be linked to the observed aphid resistance. Locomotion and antennal positioning choice tests also revealed a clear preference for susceptible lines. Although feeding studies revealed differences in the first probe indicating that the resistance factors might also be located in the peripheral layers of the plant tissue, scanning electron microscopy revealed no difference in trichrome length and density on the surface of leaves. Aphids are phloem feeders and limiting the nutrient uptake by the aphids may negatively affect their growth and development as shown here in lower weight and survival of nymphs on resistant genotypes and decreased reproductive potential, with lowest mean numbers of nymphs produced by aphids on W064 (54.8) compared to Solstice (71.9). The results indicate that resistant lines markedly alter the behaviour, reproduction and development potential of R. padi and possess both antixenosis and antibiosis type of resistance.

Use of noise cancellation earphones in out-of-booth audiometric evaluations.

OBJECTIVE: To assess the utility of noise cancelation earphones (NCE) in audiometric evaluations. DESIGN: Degree of noise reduction of Bose QuietComfort 15 NCE was assessed through probe-microphone measures and sound-field audiometry. Occlusion effects from NCE were assessed for potential effects on bone-conduction thresholds. STUDY SAMPLE: Twenty participants were tested to determine average occlusion effect values during bone-conduction testing with and without NCE. Noise reduction values of the NCE were assessed on a single subject through probe-microphone measures and sound-field testing. RESULTS: NCE sufficiently reduced ambient noise to levels acceptable for air-conduction testing as well as for bone-conduction testing for most patients when adding minimal adjustment to acceptable levels as outlined by the ANSI S3.1-1999 standard. In addition, NCE did not create a clinically significant change in the occlusion effect for bone-conduction testing. CONCLUSION: NCE placed over insert earphones provide a sound pressure level at the tympanic membrane that is below ANSI standards for routine air-conduction testing and result in sufficient ambient noise reduction for bone-conduction testing with most patients. There is no clinically significant occlusion effect from NCE during routine bone-conduction audiometry. These findings support the utility of using NCE for offsite audiometric testing.

The role of besifloxacin in the treatment of bacterial conjunctivitis.

OBJECTIVE: To evaluate the role of besifloxacin in bacterial conjunctivitis treatment. DATA SOURCES: Searches were made on MEDLINE/PubMed and EMBASE (January 2007 to January 2014) using the terms besifloxacin and Besivance. References from these publications were reviewed for additional resources. Additional information was collected from Bausch & Lomb, the manufacturer of Besivance; www.clinicaltrials.gov; and American Academy of Ophthalmology. STUDY SELECTION AND DATA EXTRACTION: English-language documents were reviewed for pharmacology, pharmacokinetics, efficacy, and safety, with priority on clinical trials. DATA SYNTHESIS: Three large randomized controlled clinical trials established the safety and efficacy of besifloxacin ophthalmic suspension 0.6% compared with placebo or active comparator (moxifloxacin ophthalmic solution 0.5%) given 3 times a day for 5 days for acute bacterial conjunctivitis (BC) treatment. Compared with placebo, besifloxacin had clinically superior bacterial eradication rates and was noninferior to moxifloxacin. Besifloxacin was compared with placebo in 2 randomized, placebo-controlled trials, dosed twice a day for 3 days. Superior efficacy was seen compared with placebo, which supports the shorter dosing schedule. Ophthalmic besifloxacin is well tolerated; the most common adverse effect (conjunctival redness) occurred in 2% of patients. Adverse effects in 1% to 2% of patients included blurred vision, eye pain, eye irritation, eye pruritus, and headache. CONCLUSION: Besifloxacin 0.6% ophthalmic suspension 3 times a day for 5 days is safe and effective for BC. Twice-a-day dosing for 3 days was also effective-a simplified regimen compared with other fluoroquinolones. Disadvantages include price and lack of a generic. Further evaluation is needed to evaluate comparative efficacy among other ocular fluoroquinolones and unlabeled uses.

Occupational exposures in the oil and gas extraction industry: State of the science and research recommendations.

The oil and gas extraction industry is rapidly growing due to horizontal drilling and high volume hydraulic fracturing (HVHF). This growth has provided new jobs and economic stimulus. The industry occupational fatality rate is 2.5 times higher than the construction industry and 7 times higher than general industry; however injury rates are lower than the construction industry, suggesting injuries are not being reported. Some workers are exposed to crystalline silica at hazardous levels, above occupational health standards. Other hazards (particulate, benzene, noise, radiation) exist. In this article, we review occupational fatality and injury rate data; discuss research looking at root causes of fatal injuries and hazardous exposures; review interventions aimed at improving occupational health and safety; and discuss information gaps and areas of needed research. We also describe Wyoming efforts to improve occupational safety in this industry, as a case example.

Quantifying the impact of Psylliodes chrysocephala injury on the productivity of oilseed rape.

BACKGROUND: Current European Union and United Kingdom legislation prohibits the use of neonicotinoid insecticidal seed treatments in oilseed rape (OSR, Brassica napus). This ban, and the reduction in efficacy of pyrethroid insecticide sprays due to resistance, has exacerbated pest pressure from the cabbage stem flea beetle (Psylliodes chrysocephala) in winter OSR. We quantified the direct impact of P. chrysocephala injury on the productivity of OSR. Leaf area was removed from young plants to simulate differing intensities of adult feeding injury alone or in combination with varying larval infestation levels. RESULTS: OSR can compensate for up to 90% leaf area loss at early growth stages, with no meaningful effect on yield. Significant impacts were observed with high infestations of more than five larvae per plant; plants were shorter, produced fewer flowers and pods, with fewer seeds per pod which had lower oil content and higher glucosinolate content. Such effects were not recorded when five larvae or fewer were present. CONCLUSION: These data confirm the yield-limiting potential of the larval stages of P. chrysocephala but suggest that the current action thresholds which trigger insecticide application for both adult and larval stages (25% leaf area loss and five larvae/plant, respectively) are potentially too low as they are below the physiological injury level where plants can fully compensate for damage. Further research in field conditions is needed to define physiological thresholds more accurately as disparity may result in insecticide applications that are unnecessary to protect yield and may in turn exacerbate the development and spread of insecticide resistance in P. chrysocephala. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Competition between isolates of Zoophthora radicans co-infecting Plutella xylostella populations.

Interactions between Zoophthora radicans isolates were studied in vitro and in vivo during infection of Plutella xylostella larvae. We distinguished between isolates within infected hosts using PCR-RFLP. Isolates obtained from P. xylostella larvae (NW386 and NW250) were more virulent than isolates from other insect hosts. Isolate NW250 was most virulent at 27°C and isolate NW386 was most virulent at 22°C. In vitro growth of all isolates except NW386 was affected by the presence of other isolates. During in vivo interactions between NW250 and NW386, the isolate with the greatest conidial concentration at inoculation infected more larvae than its competitor. Dual infected larvae were only found in treatments where inoculation concentrations of conidia were high for both isolates. Where concentrations of conidia at inoculation were low for both isolates, only NW250 caused successful infection. The implications of these results for the ecology of Z. radicans are discussed.

Quantifying inherent predictability and spatial synchrony in the aphid vector Myzus persicae: field-scale patterns of abundance and regional forecasting error in the UK.

BACKGROUND: Sugar beet is threatened by virus yellows, a disease complex vectored by aphids that reduces sugar content. We present an analysis of Myzus persicae population dynamics with and without neonicotinoid seed treatment. We use 6 years' yellow water trap and field-collected aphid data and two decades of 12.2 m suction-trap aphid migration data. We investigate both spatial synchrony and forecasting error to understand the structure and spatial scale of field counts and why forecasting aphid migrants lacks accuracy. Our aim is to derive statistical parameters to inform regionwide pest management strategies. RESULTS: Spatial synchrony, indicating the coincident change in counts across the region over time, is rarely present and is best described as stochastic. Uniquely, early season field populations in 2019 did show spatial synchrony to 90 km compared to the overall average weekly correlation length of 23 km. However, 70% of the time series were spatially heterogenous, indicating patchy between-field dynamics. Field counts lacked the same seasonal trend and did not peak in the same week. Forecasts tended to under-predict mid-season log10 counts. A strongly negative correlation between forecasting error and the proportion of zeros was shown. CONCLUSION: Field populations are unpredictable and stochastic, regardless of neonicotinoid seed treatment. This outcome presents a problem for decision-support that cannot usefully provide a single regionwide solution. Weighted permutation entropy inferred that M. persicae 12.2 m suction-trap time series had moderate to low intrinsic predictability. Early warning using a migration model tended to predict counts at lower levels than observed. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Banker Plant Bonuses? The Benefits and Risks of Including Brassicas in Field Margins to Promote Conservation Biocontrol of Specialist Pests in Oilseed Rape.

European agri-environment schemes include the use of flower-rich field margins to promote on-farm biodiversity, but species mixtures rarely include Brassicaceae. As pests of oilseed rape (OSR; Brassica napus) and their parasitoids are mostly brassica specialists, including brassica 'banker plants' in the mixtures would help support these important biocontrol agents and improve pest control throughout the crop rotation. We assessed the potential of six brassicaceous plants (replicated plots grown in the field) to enhance populations of parasitoids of OSR pests whilst minimising proliferation of their pest hosts. Fodder radish (Raphanus sativus) facilitated high production of parasitoids of the pollen beetle pest (Brassicogethes aeneus) but may proliferate Ceutorhynchus weevil pests due to low parasitism. Turnip rape (B. rapa) and the B. rapa hybrid 'Tyfon' showed potential to perform a trap cropping function for pests, but their early flowering phenology resulted in B. aeneus larvae escaping parasitisation, potentially assisting proliferation of this pest. Forage rape B. napus exhibited similarly high B. aeneus parasitoid production characteristics to R. sativus but did not potentiate problems with other pests, indicating that it would be a favourable banker plant option. Careful selection of plants in field margin mixtures is therefore needed to maximise their benefits and ideally the whole crop pest-beneficial complex needs to be studied, as focus on a single major pest risks unintended consequences with other pest problems.

Trophic links between functional groups of arable plants and beetles are stable at a national scale.

1. There is an urgent need to accurately model how environmental change affects the wide-scale functioning of ecosystems, but advances are hindered by a lack of knowledge of how trophic levels are linked across space. It is unclear which theoretical approach to take to improve modelling of such interactions, but evidence is gathering that linking species responses to their functional traits can increase understanding of ecosystem dynamics. Currently, there are no quantitative studies testing how this approach might improve models of multiple, trophically interacting species, at wide spatial scales. 2. Arable weeds play a foundational role in linking food webs, providing resources for many taxa, including carabid beetles that feed on their seeds and weed-associated invertebrate prey. Here, we model associations between weeds and carabids across farmland in Great Britain (GB), to test the hypothesis that wide-scale trophic links between these groups are structured by their species functional traits. 3. A network of c. 250 arable fields, covering four crops and most lowland areas of GB, was sampled for weed, carabid and invertebrate taxa over 3 years. Data sets of these groups were closely matched in time and space, and each contained numerous species with a range of eco-physiological traits. The consistency of trophic linkages between multiple taxa sharing functional traits was tested within multivariate and log-linear models. 4. Robust links were established between the functional traits of taxa and their trophic interactions. Autumn-germinating, small-seeded weeds were associated with smaller, spring-breeding carabids, more specialised in seed feeding, whereas spring-germinating, large-seeded weeds were associated with a range of larger, autumn-breeding omnivorous carabids. These relationships were strong and dynamic, being independent of changes in invertebrate food resources and consistent across sample dates, crops and regions of GB. 5. We conclude that, in at least one system of interacting taxa, functional traits can be used to predict consistent, wide-scale trophic links. This conceptual approach is useful for assessing how perturbations affecting lower trophic levels are ramified throughout ecosystems and could be used to assess how environmental change affects a wider range of secondary consumers.

Using adult mosquitoes to transfer insecticides to Aedes aegypti larval habitats.

Vector control is a key means of combating mosquito-borne diseases and the only tool available for tackling the transmission of dengue, a disease for which no vaccine, prophylaxis, or therapeutant currently exists. The most effective mosquito control methods include a variety of insecticidal tools that target adults or juveniles. Their successful implementation depends on impacting the largest proportion of the vector population possible. We demonstrate a control strategy that dramatically improves the efficiency with which high coverage of aquatic mosquito habitats can be achieved. The method exploits adult mosquitoes as vehicles of insecticide transfer by harnessing their fundamental behaviors to disseminate a juvenile hormone analogue (JHA) between resting and oviposition sites. A series of field trials undertaken in an Amazon city (Iquitos, Peru) showed that the placement of JHA dissemination stations in just 3-5% of the available resting area resulted in almost complete coverage of sentinel aquatic habitats. More than control mortality occurred in 95-100% of the larval cohorts of Aedes aegypti developing at those sites. Overall reductions in adult emergence of 42-98% were achieved during the trials. A deterministic simulation model predicts amplifications in coverage consistent with our observations and highlights the importance of the residual activity of the insecticide for this technique.

Use of honey bees (Apis mellifera L.) to detect the presence of Mediterranean fruit fly (Ceratitis capitata Wiedemann) larvae in Valencia oranges.

BACKGROUND: When fruit deteriorates a characteristic profile of volatile chemicals is produced that is different from that produced by healthy fruits. The identification of such chemicals allows the possibility of monitoring the fruit for early signs of deterioration with biological sensors. The use of honey bees and other insects as biological sensors is well known. This study aimed to identify the volatiles produced by oranges infested with larvae of the Mediterranean fruit fly and to test the ability of honey bees, conditioned to this volatile chemical profile, to detect such oranges. RESULTS: Seventeen compounds that were present in higher concentrations in the volatile profiles of infested oranges than in those of insect-free fruits were mixed at the same relative concentrations as those in the collected volatiles of infested oranges. The synthetic mixture was used to train honey bees by classical Pavlovian conditioning and subsequent tests showed that they were then able to discriminate between medfly-infested and uninfested oranges. CONCLUSION: This study demonstrates an innovative way of detecting, at an early stage, the symptoms of damage to oranges by the Mediterranean fruit fly.

Use of quantitative PCR to understand within-host competition between two entomopathogenic fungi.

Interactions between the entomopathogenic fungi Zoophthora radicans and Pandora blunckii infecting larvae of Plutella xylostella were investigated. This is the first report to quantify within-host growth of one fungus in the presence of another competing for the same host resource using quantitative PCR (qPCR) at regular time points during the infection process. In larvae inoculated only with Z. radicans, there was a cumulative increase in the quantity of Z. radicans DNA throughout the time course of infection. However, in dual-inoculated larvae, there was an initial accelerated rate of growth of Z. radicans compared to when it was inoculated alone, but by the time of host death it had been effectively excluded by P. blunckii. The implications of these results for co-existence of these fungal pathogens in the field are discussed.

Pharmacy Emergency Preparedness and Response (PEPR): a proposed framework for expanding pharmacy professionals' roles and contributions to emergency preparedness and response during the COVID-19 pandemic and beyond.

Background: Pharmacists have long been involved in public health and emergency preparedness and response (EP&R), including through preventive measures such as screening, vaccinations, testing, medical and pharmaceutical countermeasures, as well as ensuring medication safety and access during natural disasters and pandemics. Pharmacy professionals are considered essential partners in response to the ongoing COVID-19 pandemic. Community and hospital pharmacies are expanding services and hours to provide essential services, putting pharmacists and their co-workers at the frontlines for patient care and safety to improve public health. In addition, pharmacy professionals are increasingly integrating into global, national, state and local EP&R efforts, including into interprofessional teams, such as Medical Reserve Corps (MRCs). However, lacunae exist for further integration of pharmacists into public health and safety initiatives. There are increasing opportunities and recommendations that should be expanded upon to provide improved patient care and population health interventions, and to ensure healthcare worker and public health safety. Objective: Develop a Pharmacy Emergency Preparedness and Response (PEPR) Framework and recommendations for pharmacy professional pathways towards full integration within public health EP&R efforts (such as the COVID-19 pandemic), and enhanced recognition of pharmacists' skills, roles and contributions as integral members of the interprofessional healthcare team. Methods: This paper draws on the American Society of Health-System Pharmacists (ASHP) 2003 Statement on the Role of Health-System Pharmacists in Emergency Preparedness and lessons learned from previous and current public health emergencies, such as the 2009 H1N1 pandemic and the current COVID-19 pandemic, to provide expanded guidance for pharmacists and pharmacy professionals across all practice settings in EP&R. The proposed PEPR framework also incorporates information and recommendations from The Pharmacy Organizations' Joint Policy Recommendations to Combat the COVID-19 Pandemic (March 2020), CDC-NIOSH, International Pharmaceutical Federation (FIP) Guidance, health departments and emergency preparedness guidance and resources, Boards of Pharmacy, and other pharmacy professional organizations and educational institutions. Results: Based on methods and resources utilized in developing this proposed PEPR Framework, five key focus areas were identified, as follows:1)Emergency preparedness and response2)Operations management3)Patient care and population health interventions4)Public health pharmacy education and continuing professional education5)Evaluation, research, and dissemination for impact and outcomes. Conclusion: Pharmacists and pharmacy professionals have been at the frontlines in responding to the COVID-19 pandemic. Yet, challenges remain, such as limited availability of personal protection equipment, high risk of infectious exposures inherent in healthcare professions, and legislative hurdles resulting in lack of provider status and related reimbursements. Recommendations to enhance pharmacy's scope as public health professionals involved in EP&R include targeted training and education on key framework areas and policymaking. Pharmacy professionals should further integrate with interdisciplinary public health teams. Additional research and dissemination on impacts and outcomes of EP&R can enhance recognition of pharmacy professionals' contribution and value during public health emergencies. The proposed PEPR Framework can be utilized to develop, implement, evaluate, and disseminate results in order to strengthen existing efforts and to establish new initiatives in EP&R.

Empowering Public Health Pharmacy Practice-Moving from Collaborative Practice Agreements to Provider Status in the U.S.

This article describes the history and evolution of pharmacist-physician collaborative practice agreements (CPAs) in the United States with future directions to support pharmacists' provider status as the profession continues to evolve from product-oriented to patient-centered care and population health. The pharmacy profession has a long history of dispensing and compounding, with the addition of clinical roles in the late 20th century. These clinical roles have continued to expand into diverse arenas such as communicable and non-communicable diseases, antimicrobial stewardship, emergency preparedness and response, public health education and health promotion, and critical and emergency care. Pharmacists continue to serve as integral members of interprofessional and interdisciplinary healthcare teams. In this context, CPAs allow pharmacists to expand their roles in patient care and may be considered as a step towards securing provider status. Moving beyond CPAs to a provider status would enable pharmacists to be reimbursed for cognitive services and promote integrated public health delivery models.

Development of spontaneous recurrent seizures after kainate-induced status epilepticus.

Acquired epilepsy (i.e., after an insult to the brain) is often considered to be a progressive disorder, and the nature of this hypothetical progression remains controversial. Antiepileptic drug treatment necessarily confounds analyses of progressive changes in human patients with acquired epilepsy. Here, we describe experiments testing the hypothesis that development of acquired epilepsy begins as a continuous process of increased seizure frequency (i.e., proportional to probability of a spontaneous seizure) that ultimately plateaus. Using nearly continuous surface cortical and bilateral hippocampal recordings with radiotelemetry and semiautomated seizure detection, the frequency of electrographically recorded seizures (both convulsive and nonconvulsive) was analyzed quantitatively for approximately 100 d after kainate-induced status epilepticus in adult rats. The frequency of spontaneous recurrent seizures was not a step function of time (as implied by the "latent period"); rather, seizure frequency increased as a sigmoid function of time. The distribution of interseizure intervals was nonrandom, suggesting that seizure clusters (i.e., short interseizure intervals) obscured the early stages of progression, and may have contributed to the increase in seizure frequency. These data suggest that (1) the latent period is the first of many long interseizure intervals and a poor measure of the time frame of epileptogenesis, (2) epileptogenesis is a continuous process that extends much beyond the first spontaneous recurrent seizure, (3) uneven seizure clustering contributes to the variability in occurrence of epileptic seizures, and (4) the window for antiepileptogenic therapies aimed at suppressing acquired epilepsy probably extends well past the first clinical seizure.

Oxidative stress-mediated mitochondrial dysfunction contributes to angiotensin II-induced nonalcoholic fatty liver disease in transgenic Ren2 rats.

Emerging evidence indicates that impaired mitochondrial fatty acid beta-oxidation plays a key role in liver steatosis. We have recently demonstrated that increased angiotensin (ANG) II causes progressive hepatic steatosis associated with oxidative stress; however, the underlying mechanisms remain unclear. We hypothesized that ANG II causes hepatic mitochondrial oxidative damage and impairs mitochondrial beta-oxidation, thereby leading to hepatic steatosis. We used the Ren2 rat with elevated endogenous ANG II levels to evaluate mitochondrial ultrastructural changes, gene expression levels, and beta-oxidation. Compared with Sprague-Dawley littermates, Ren2 livers exhibited mitochondrial damage and reduced beta-oxidation, as evidenced by ultrastructural abnormalities, decrease of mitochondrial content, percentage of palmitate oxidation to CO(2), enzymatic activities (beta-HAD and citrate synthase), and the expression levels of cytochrome c, cytochrome c oxidase subunit 1, and mitochondrial transcription factor A. These abnormalities were improved with either ANG II receptor blocker valsartan or superoxide dismutase/catalase mimetic tempol treatment. Both valsartan and tempol substantially attenuated mitochondrial lipid peroxidation in Ren2 livers. Interestingly, there was no difference in the expression of key enzymes (ACC1 and FAS) for fatty acid syntheses and their transcription factors (SREBP-1c and ChREBP) between Sprague-Dawley, untreated Ren2, and valsartan- or tempol-treated Ren2 rats. These results document that ANG II induces mitochondrial oxidative damage and impairs mitochondrial beta-oxidation, contributing to liver steatosis.

EEG spike activity precedes epilepsy after kainate-induced status epilepticus.

PURPOSE: Chronic epilepsy frequently develops after brain injury, but prediction of which individual patient will develop spontaneous recurrent seizures (i.e., epilepsy) is not currently possible. Here, we use continuous radiotelemetric electroencephalography (EEG) and video monitoring along with automated computer detection of EEG spikes and seizures to test the hypothesis that EEG spikes precede and are correlated with subsequent spontaneous recurrent seizures. METHODS: The presence and pattern of EEG spikes was studied during long recording epochs between the end of status epilepticus (SE) induced by three different doses of kainate and the onset of chronic epilepsy. RESULTS: The presence of spikes, and later spike clusters, over several days after SE before the first spontaneous seizure, was consistently associated with the development of chronic epilepsy. The rate of development of epilepsy (i.e., increase in seizure frequency) was strongly correlated with the frequency of EEG spikes and the cumulative number of EEG spikes after SE. CONCLUSIONS: The temporal features of EEG spikes (i.e., their presence, frequency, and pattern [clusters]) when analyzed over prolonged periods, may be a predictive biomarker for the development of chronic epilepsy after brain injury. Future clinical trials using prolonged EEG recordings may reveal the diagnostic utility of EEG spikes as predictors of subsequent epilepsy in brain-injured humans.

Zinc and the Msc2 zinc transporter protein are required for endoplasmic reticulum function.

In this report, we show that zinc is required for endoplasmic reticulum function in Saccharomyces cerevisiae. Zinc deficiency in this yeast induces the unfolded protein response (UPR), a system normally activated by unfolded ER proteins. Msc2, a member of the cation diffusion facilitator (CDF) family of metal ion transporters, was previously implicated in zinc homeostasis. Our results indicate that Msc2 is one route of zinc entry into the ER. Msc2 localizes to the ER when expressed at normal levels. UPR induction in low zinc is exacerbated in an msc2 mutant. Genetic and biochemical evidence indicates that this UPR induction is due to genuine ER dysfunction. Notably, we found that ER-associated protein degradation is defective in zinc-limited msc2 mutants. We also show that the vacuolar CDF proteins Zrc1 and Cot1 are other pathways of ER zinc acquisition. Finally, zinc deficiency up-regulates the mammalian ER stress response indicating a conserved requirement for zinc in ER function among eukaryotes.

Pollination biology of fruit-bearing hedgerow plants and the role of flower-visiting insects in fruit-set.

BACKGROUND AND AIMS: In the UK, the flowers of fruit-bearing hedgerow plants provide a succession of pollen and nectar for flower-visiting insects for much of the year. The fruits of hedgerow plants are a source of winter food for frugivorous birds on farmland. It is unclear whether recent declines in pollinator populations are likely to threaten fruit-set and hence food supply for birds. The present study investigates the pollination biology of five common hedgerow plants: blackthorn (Prunus spinosa), hawthorn (Crataegus monogyna), dog rose (Rosa canina), bramble (Rubus fruticosus) and ivy (Hedera helix). METHODS: The requirement for insect pollination was investigated initially by excluding insects from flowers by using mesh bags and comparing immature and mature fruit-set with those of open-pollinated flowers. Those plants that showed a requirement for insect pollination were then tested to compare fruit-set under two additional pollination service scenarios: (1) reduced pollination, with insects excluded from flowers bagged for part of the flowering period, and (2) supplemental pollination, with flowers hand cross-pollinated to test for pollen limitation. KEY RESULTS: The proportions of flowers setting fruit in blackthorn, hawthorn and ivy were significantly reduced when insects were excluded from flowers by using mesh bags, whereas fruit-set in bramble and dog rose were unaffected. Restricting the exposure of flowers to pollinators had no significant effect on fruit-set. However, blackthorn and hawthorn were found to be pollen-limited, suggesting that the pollination service was inadequate in the study area. CONCLUSIONS: Ensuring strong populations of insect pollinators may be essential to guarantee a winter fruit supply for birds in UK hedgerows.

Identification of human-derived volatile chemicals that interfere with attraction of the Scottish biting midge and their potential use as repellents.

The Scottish biting midge, Culicoides impunctatus (Diptera: Ceratopogonidae), is a major pest in Scotland, causing a significant impact to the Scottish tourist and forestry industries. C. impunctatus is a generalist feeder, preferring to feed on large mammals, and is notorious for its attacks on humans. Until now, there was anecdotal evidence for differential attraction of female host-seeking C. impunctatus to individual human hosts, and the mechanism for this phenomenon was unknown. Using extracts of human odor collected by air entrainment, electroantennogram recordings to identify the physiologically active components, followed by behavioral assays, we show, for the first time, the differential attraction of female C. impunctatus to human odors and the chemical basis for this phenomenon. Certain chemicals, found in greater amounts in extracts that cause low attractiveness to midges, elicit a repellent effect in laboratory assays and repellency trials in the field. Differences in the production of these natural human-derived compounds could help to explain differential "attractiveness" between different human hosts. A mixture of two compounds in particular, 6-methyl-5-hepten-2-one and geranylacetone [(E)-6,10-dimethylundeca-5,9-dien-2-one], showed significant repellency (87, 77.4, 74.2, and 31.6% at hours 0, 1, 2, and 3, respectively) in the field and have the potential to be developed as novel repellents.