3,000 research outputs found
Microbial Gut Diversity of Africanized and European Honey Bee Larval Instars
The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae
Spectral absorption of biomass burning aerosol determined from retrieved single scattering albedo during ARCTAS
Actinic flux, as well as aerosol chemical and optical properties, were measured aboard the NASA DC-8 aircraft during the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) mission in Spring and Summer 2008. These measurements were used in a radiative transfer code to retrieve spectral (350-550 nm) aerosol single scattering albedo (SSA) for biomass burning plumes encountered on 17 April and 29 June. Retrieved SSA values were subsequently used to calculate the absorption Angstrom exponent (AAE) over the 350-500 nm range. Both plumes exhibited enhanced spectral absorption with AAE values that exceeded 1 (6.78 ± 0.38 for 17 April and 3.34 ± 0.11 for 29 June). This enhanced absorption was primarily due to organic aerosol (OA) which contributed significantly to total absorption at all wavelengths for both 17 April (57.7%) and 29 June (56.2%). OA contributions to absorption were greater at UV wavelengths than at visible wavelengths for both cases. Differences in AAE values between the two cases were attributed to differences in plume age and thus to differences in the ratio of OA and black carbon (BC) concentrations. However, notable differences between AAE values calculated for the OA (AAEOA) for 17 April (11.15 ± 0.59) and 29 June (4.94 ± 0.19) suggested differences in the plume AAE values might also be due to differences in organic aerosol composition. The 17 April OA was much more oxidized than the 29 June OA as denoted by a higher oxidation state value for 17 April (+0.16 vs. -0.32). Differences in the AAEOA, as well as the overall AAE, were thus also possibly due to oxidation of biomass burning primary organic aerosol in the 17 April plume that resulted in the formation of OA with a greater spectral-dependence of absorption. © Author(s) 2012. CC Attribution 3.0 License
Neutron Stars as Type-I Superconductors
In a recent paper by Link, it was pointed out that the standard picture of
the neutron star core composed of a mixture of a neutron superfluid and a
proton type-II superconductor is inconsistent with observations of a long
period precession in isolated pulsars. In the following we will show that an
appropriate treatment of the interacting two-component superfluid (made of
neutron and proton Cooper pairs), when the structure of proton vortices is
strongly modified, may dramatically change the standard picture, resulting in a
type-I superconductor. In this case the magnetic field is expelled from the
superconducting regions of the neutron star leading to the formation of the
intermediate state when alternating domains of superconducting matter and
normal matter coexist.Comment: 4 page
Status and Trends of Phragmites australis invasion within constructed wetlands in Virginia
Part I. Field GPS Mapping of P. australis Populations. Kirk J. Havens, Harry Berquist, and Walter I. Priest, Ill
Part II. Evaluating the Use of Multispectral Imagery for Identifying and Quantifying P. australis Populations in Created Wetlands. James E. Perry and John Anderson
Part Ill. A Summary of Methods for Controlling Phragmites australis. Libby Norris, James E. Perry, and Kirk J. Haven
Reconstruction of a meteotsunami in Lake Erie on 27 May 2012: Roles of atmospheric conditions on hydrodynamic response in enclosed basins
On 27 May 2012, atmospheric conditions gave rise to two convective systems that generated a series of waves in the meteotsunami band on Lake Erie. The resulting waves swept three swimmers a 0.5 mi offshore, inundated a marina, and may have led to a capsized boat along the southern shoreline. Analysis of radial velocities from a nearby radar tower in combination with coastal meteorological observation indicates that the convective systems produced a series of outflow bands that were the likely atmospheric cause of the meteotsunami. In order to explain the processes that led to meteotsunami generation, we model the hydrodynamic response to three meteorological forcing scenarios: (i) the reconstructed atmospheric disturbance from radar analysis, (ii) simulated conditions from a highâresolution weather model, and (iii) interpolated meteorological conditions from the NOAA Great Lakes Coastal Forecasting System. The results reveal that the convective systems generated a series of waves incident to the southern shore of the lake that reflected toward the northern shoreline and reflected again to the southern shore, resulting in spatial wave focusing and edge wave formation that combined to impact recreational users near Cleveland, OH. This study illustrates the effects of meteotsunami development in an enclosed basin, including wave reflection, focusing, and edge wave formation as well as temporal lags between the causative atmospheric conditions and arrival of dangerous wave conditions. As a result, the ability to detect these extreme storms and predict the hydrodynamic response is crucial to reducing risk and building resilient coastal communities.Key Points:Radarâbased velocity allows for detection of meteotsunamiâinducing frontWave reflection, focusing, and edge waves led to meteotsunami conditionsEnclosed basins can induce temporal lags between storm front and wave responsePeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145384/1/jgrc21485_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145384/2/jgrc21485-sup-0001-2015JC010883-s01.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145384/3/jgrc21485.pd
Relationship of Tissue Dimensions and Three Captive Bolt Application Sites on Cadaver Heads from Mature Swine (\u3ci\u3eSus scrofa domesticus\u3c/i\u3e) \u3c 200 kg Body-weight
Penetrating captive bolt (PCB) is a common method of euthanasia for swine but has not been evaluated for mature swine \u3c 200 kg body weight (BW). The objectives were to determine tissue depth, brain contact plane, and visible brain tissue damage (brain damage[BD]) for the common FRONTAL (F) and alternative TEMPORAL (T) and BEHIND EAR (BE) placements for PCB use on sows and boars weighing \u3c 200 kg. Cadaver heads were obtained from 30 sows and 30 boars (estimated BW, mean ± SD; sows: 165.8 ± 22.4 kg; boars: 173.6 ± 21.4 kg) from a slaughter establishment after electrical stunning and exsanguination. Heads were cooled at 2 to 4 °C for approximately 64 h. A Jarvis PAS-Type P 0.25R PCB with a Long Stunning Rod Nosepiece Assembly and a 3.5 GR power load was used for all PCB applications at the following placements: Fâ3.5 cm superior to the optic orbits at midline, Tâat the depression posterior to the lateral canthus of the eye within the plane between the lateral canthus and the base of the ear, or BEâdirectly caudal to the pinna of the ear on the same plane as the eyes and targeting the middle of the opposite eye. For sows, the bolt path was in the brain for 10/10 (100.0%, 95% CI: 69.2% to 100.0%) F, T, and BE heads. In heads that could reliably be assessed for BD, BD was detected in 10/10 (100.0%, 95% CI: 69.2% to 100.0%) F heads, 9/9 (100.0%, 95% CI: 66.4% to 100.0%) T heads, and 0/10 (0.0%, 95% CI: 0.0% to 30.1%) BE heads. For boars, the bolt path was in the plane of the brain for 8/9 (88.9%, 95% CI: 51.8% to 99.7%) F heads, 9/10 (90.0%, 95% CI: 55.5% to 99.7%) T heads, and 11/11 (100.0%, 95% CI: 71.5% to 100.0%) BE heads. In heads that could reliably be assessed for BD, BD was detected in 8/9 (88.9%, 95% CI: 51.7% to 99.7%) F heads, 7/10 (70.0%, 95% CI: 34.8% to 93.3%) T heads, and 4/11 (36.4%, 95% CI: 10.9% to 69.2%) BE heads. Tissue depth was reported as mean ± SE followed by 95% one-sided upper reference limit (URL). For sows, total tissue thickness differed (P \u3c 0.05) between placements (F: 49.41 ± 2.74 mm, URL: 70.0 mm; T: 62.83 ± 1.83 mm, URL: 76.6 mm; BE: 84.63 ± 3.67 mm; URL: 112.3 mm). Total tissue thickness differed (P \u3c 0.05) between placements for boars (F: 54.73 ± 3.23 mm, URL: 77.6 mm; T: 70.72 ± 3.60 mm, URL: 96.3 mm; BE: 92.81 ± 5.50 mm; URL: 135.3 mm). For swine between 120 and 200 kg BW, the F placement may have the greatest likelihood for successful euthanasia due to the least total tissue thickness and may present less risk for failure than the T and BE placements
Breast cancer risk reduction:is it feasible to initiate a randomised controlled trial of a lifestyle intervention programme (ActWell) within a national breast screening programme?
BackgroundBreast cancer is the most commonly diagnosed cancer and the second cause of cancer deaths amongst women in the UK. The incidence of the disease is increasing and is highest in women from least deprived areas. It is estimated that around 42% of the disease in post-menopausal women could be prevented by increased physical activity and reductions in alcohol intake and body fatness. Breast cancer control endeavours focus on national screening programmes but these do not include communications or interventions for risk reductionThis study aimed to assess the feasibility of delivery, indicative effects and acceptability of a lifestyle intervention programme initiated within the NHS Scottish Breast Screening Programme (NHSSBSP).MethodsA 1:1 randomised controlled trial (RCT) of the 3 month ActWell programme (focussing on body weight, physical activity and alcohol) versus usual care conducted in two NHSSBSP sites between June 2013 and January 2014. Feasibility assessments included recruitment, retention, and fidelity to protocol. Indicative outcomes were measured at baseline and 3 month follow-up (body weight, waist circumference, eating and alcohol habits and physical activity. At study end, a questionnaire assessed participant satisfaction and qualitative interviews elicited women¿s, coaches and radiographers¿ experiences. Statistical analysis used Chi squared tests for comparisons in proportions and paired t tests for comparisons of means. Linear regression analyses were performed, adjusted for baseline values, with group allocation as a fixed effectResultsA pre-set recruitment target of 80 women was achieved within 12 weeks and 65 (81%) participants (29 intervention, 36 control) completed 3 month assessments. Mean age was 58¿±¿5.6 years, mean BMI was 29.2¿±¿7.0 kg/m2 and many (44%) reported a family history of breast cancer.The primary analysis (baseline body weight adjusted) showed a significant between group difference favouring the intervention group of 2.04 kg (95%CI ¿3.24 kg to ¿0.85 kg). Significant, favourable between group differences were also detected for BMI, waist circumference, physical activity and sitting time. Women rated the programme highly and 70% said they would recommend it to others.ConclusionsRecruitment, retention, indicative results and participant acceptability support the development of a definitive RCT to measure long term effects.Trial registrationThe trial was registered with Current Controlled Trials (ISRCTN56223933)
The impact of pollen consumption on honey bee (Apis mellifera) digestive physiology and carbohydrate metabolism
Carbohydrate-active enzymes play an important role in the honey bee (Apis mellifera) due to its dietary specialization on plant-based nutrition. Secretory glycoside hydrolases (GHs) produced in worker head glands aid in the processing of floral nectar into honey and are expressed in accordance with the age-based division of labor. Pollen utilization by the honey bee has been investigated in considerable detail, but little is known about the metabolic fate of indigestible carbohydrates and glycosides in pollen biomass. Here, we demonstrate that pollen consumption stimulates the hydrolysis of sugars that are toxic to the bee (xylose, arabinose, mannose). GHs produced in the head accumulate in the midgut and persist in the hindgut that harbors a core microbial community composed of approximately 108 bacterial cells. Pollen consumption significantly impacted total and specific bacterial abundance in the digestive tract. Bacterial isolates representing major fermentative gut phylotypes exhibited primarily membrane-bound GH activities that may function in tandem with soluble host enzymes retained in the hindgut. Additionally, we found that plant-originating -galactosidase activity in pollen may be sufficient, in some cases, for probable physiological activity in the gut. These findings emphasize the potential relative contributions of host, bacteria, and pollen enzyme activities to carbohydrate break- down, which may be tied to gut microbiome dynamics and associated host nutrition
- âŠ