The bumble bees (Hymenoptera: Apidae: Bombus) of Arkansas, fifty years later

Many species of bumble bees (Hymenoptera: Apidae: Bombus Latreille) are declining throughout their ranges in North America, yet detecting population trends can be difficult when historical survey data are lacking.  In the present study, contemporary data is compared to a 1965 survey to detect changes in bumble bee distributions throughout Arkansas.  Using county-level records as a point of comparison to look for changes in state-wide occurrence among species over time, we find that state-level changes reflect national trends.  Contemporary records of Bombus bimaculatus Cresson and B. impatiens Cresson have more than tripled, while records for B. pensylvanicus (De Geer) show a decline to 61% of historical levels.  Although B. fervidus (Fabricius) has been reported infrequently in the state, misidentifications may have led to an overestimation of the state’s species richness.  In addition to an updated assessment of the bumble bees of Arkansas, we also provide new, localized information on the seasonal phenology and plant preferences of each species that can be used to guide conservation efforts

Whole-genome doubling affects pre-mirna expression in plants

Whole-genome doubling (polyploidy) is common in angiosperms. Several studies have indicated that it is often associated with molecular, physiological, and phenotypic changes. Mounting evidence has pointed out that micro-RNAs (miRNAs) may have an important role in whole-genome doubling. However, an integrative approach that compares miRNA expression in polyploids is still lacking. Here, a re-analysis of already published RNAseq datasets was performed to identify microRNAs’ precursors (pre-miRNAs) in diploids (2x) and tetraploids (4x) of five species (Arabidopsis thaliana L., Morus alba L., Brassica rapa L., Isatis indigotica Fort., and Solanum commersonii Dun). We found 3568 pre-miRNAs, three of which (pre-miR414, pre-miR5538, and pre-miR5141) were abundant in all 2x, and were absent/low in their 4x counterparts. They are predicted to target more than one mRNA transcript, many belonging to transcription factors (TFs), DNA repair mechanisms, and related to stress. Sixteen pre-miRNAs were found in common in all 2x and 4x. Among them, pre-miRNA482, pre-miRNA2916, and pre-miRNA167 changed their expression after polyploidization, being induced or repressed in 4x plants. Based on our results, a common ploidy-dependent response was triggered in all species under investigation, which involves DNA repair, ATP-synthesis, terpenoid biosynthesis, and several stress-responsive transcripts. In addition, an ad hoc pre-miRNA expression analysis carried out solely on 2x vs. 4x samples of S. commersonii indicated that ploidy-dependent pre-miRNAs seem to actively regulate the nucleotide metabolism, probably to cope with the increased requirement for DNA building blocks caused by the augmented DNA content. Overall, the results outline the critical role of microRNA-mediated responses following autopolyploidization in plants

Answer to the remarks on superconductivity in PdH

Abstract This is the answer to the letter of Baranowski and Debowska [Baranowski and Debowska, J. Alloys Compd. 437 (2007) L4–L5]

Timing of Invasion by Africanized Bees Coincides with Local Extinction of a Specialized Pollinator of a Rare Poppy in Utah, USA

The introduction of exotic species can have profound impacts on mutualisms between native species in invaded areas. However, determining whether a new invader has impacted native species depends on accurately reconstructing the invasion timing. The arrival of Africanized honey bees (AHB) in southern Utah at some point between 1994 and 2011 has recently been implicated in the local extinction of Perdita meconis, a native specialist pollinator of an endangered poppy, Arctomecon humilis. Although AHBs were purportedly first detected in southern Utah in 2008, their presence in nearby Nevada, Arizona, and New Mexico by 1998–2001 suggests that they may have been present in Utah much earlier. We refined the arrival date of AHBs in southern Utah by using a molecular marker to determine maternal ancestry of museum specimens collected between 2000 and 2008. We found that AHBs were present in southern Utah from 2000 onwards, advancing the arrival date of this invader by at least 8 years. This lends credence to the hypothesis that AHBs played a critical role in the local extinction of P. meconis in Utah. This work also highlights the importance of vouchering even common species such as honey bees in museum collections to serve future research needs

Who comes first. rescheduling endoscopic activity after the acute phase of the Covid 19 pandemic

The current health emergency caused by the COVID19 pandemic has caused an abrupt reduction in all ordinary endoscopic activities [1]. Our endoscopy unit, usually overloaded with procedures, has reduced its activities to immediate urgencies only, as recommended by position statements of many scientific societies [2–4]. After the most critical phase of the emergency, the need to evaluate the relative urgency of the endoscopic procedures was addressed. In our endoscopic academic tertiary referral unit, about 300 endoscopic procedures from March 16 to May 2 were suspended. According to local (hospital) and regional health department indications, outpatient services have been reorganised, by remodulating time slots for procedures, controlling and filtering patients’ access to the unit and reviewing the indications for each single endoscopic procedure programmed but not performed. Procedures initially classified as urgent (by 48 hours, n. 77) and short (by 10 days, n. 68) were directly rescheduled and performed. Furthermore, we decided to interview all the patients of postponed endoscopic procedures by phone calls carried out by trainees, tutored by a senior component of the endoscopy unit. A systematic questionnaire was developed based on the following items: demographic and clinical patient characteristics, current conditions, gastrointestinal signs and symptoms, exam indications and priority classes assigned by the general practitioner or other physicians, time and results of previous endoscopic examinations, laboratory tests, ongoing treatments. Results of the phone interview and any additional clinical documentation e-mailed by the patient was evaluated and archived including date and time of the interview with the patient’s informed consent. Based on the results of the reassessment, patients were rescheduled stratifing the procedures in the following 4 priority cl

Nonuniversal temperature dependencies of the low-frequency ac magnetic susceptibility in high-T c superconductors

The complex ac magnetic susceptibilities ({\ensuremath{\chi}}_{n}={\ensuremath{\chi}}_{n}^{\ensuremath{'}}+i{\ensuremath{\chi}}_{n}^{\ensuremath{''}}) of high-${T}_{c}$ superconductors in absence of dc fields have been studied by numerically solving the nonlinear diffusion equation for the magnetic flux, where the diffusivity is determined by the resistivity. In our approach the parallel resistor model between the creep and flux flow resistivities is used, so that the crossover between different flux dynamic processes (thermally activated flux flow, flux creep, flux flow) can naturally arise. For this reason we remark that, as the frequency increases, the presence of a different nonlinearity in different regions of the I\ensuremath{-}V characteristic determines nonuniversal temperature dependencies of the {\ensuremath{\chi}}_{n}, i.e., the {\ensuremath{\chi}}_{n} are found to be not universal functions of a frequency- and temperature-dependent single parameter. Moreover, the actual frequency-dependent behavior is also shown to be strictly related to the particular pinning model chosen for the simulations. Indeed, for large values of the reduced pinning potential $(U/KTg~220)$ and for increasing frequency, a transition has been observed between dynamic regimes dominated by creep and flux flow processes. On the other hand, for smaller reduced pinning potentials, a transition from the thermally activated flux flow (Taff) to the flow regime occurs. In qualitative agreement with available experimental data but in contrast with previously used simpler models, the amplitude of the peak of the imaginary part of the first harmonic is shown to be frequency dependent. Moreover the frequency dependence of its peak temperature shows large discrepancies with approximated analytical predictions. Finally, the shapes of the temperature dependencies of the higher harmonics are found to be strongly affected by the frequency

Mitochondrial DNA genetic diversity of honey bees, Apis mellifera, in Hawaii

International audienceAbstractHoney bees, Apis mellifera, in the Hawaiian Islands are geographically isolated from honey bees in mainland United States. We conducted a study on the mitochondrial DNA genetic diversity of honey bees from seven of the Hawaiian Islands by sequencing the intergenic region between the Cytochrome Oxidase I and Cytochrome Oxidase II genes (COI-COII). We observed a total of 10 haplotypes from 235 samples collected from 2009 to 2014. Haplotypes belonged to the A. mellifera C lineage (64 %), M lineage (35 %), and O lineage (1 %). Four of the five C lineage haplotypes found were common among queen breeders in continental United States (C1, C2, C11, C19) and accounted for 99 % of the C lineage bees. Haplotype C33 (1 %) has been observed in feral honey bee populations in continental United States. For the M lineage, which includes the dark honey bee, A. m. mellifera, four haplotypes were observed (M3, M4c”’, M7 and M70), with a novel haplotype unique to Hawaii, M70, being the second most common. Five islands had M lineage haplotypes, with their frequency ranging from 70 % on Maui to 22 % on Molokai. Two individuals of the O lineage, haplotype O1, were found on Oahu. Among the islands, Oahu and Maui, had the greatest amount of haplotypic diversity (haplotypic diversity (Hd) = 0.76 and 0.75). Lanai and Kahoolawe had only one haplotype, C1, present

Nosema bombi (Microsporidia: Nosematidae) and trypanosomatid prevalence in spring bumble bee queens (Hymenoptera: Apidae: Bombus) in Kansas

Citation: Tribodi, A., Cibils-Stewart, X., McCornack, B., & Szlanski, A. (2014). Nosema bombi (Microsporidia: Nosematidae) and Trypanosomatid Prevalence in Spring Bumble Bee Queens (Hymenoptera: Apidae: Bombus) in Kansas. Journal of the Entomological Society, 87(2), 225-233. https://doi.org/10.2317/JKES130730.1Several species of bumble bees are declining in the United States; these declining populations often show higher prevalence of Nosema bombi, a microsporidian pathogen. To date, surveys of bumble bee pathogens in the United States have only been conducted on workers and males, yet the health of a population is ultimately dependent on the success of colony-founding queens. We conducted a molecular-diagnostic survey of the prevalence of N. bombi and trypanosomatids, such as Crithidia bombi, in six species of spring queens (n  =  142) collected in 2011 and 2013 at three sites in central Kansas. Nosema bombi was found in 27% of Bombus pensylvanicus and 13% of B. auricomus but was not found in the other species sampled. Trypanosomatids were only found in B. pensylvanicus (9%) during the May 2013 sampling period. The high prevalence of N. bombi in B. pensylvanicus is consistent with other surveys for this pathogen in other castes, but the high prevalence of N. bombi in B. auricomus is a novel finding. Although the conservation status of B. auricomus has not been thoroughly assessed, two recently published surveys showed that B. auricomus were less common in portions of the species' range. Based on those findings and an oft-cited link between N. bombi prevalence and bumble bee species' decline (e.g., B. pensylvanicus) in other studies, our findings suggest B. auricomus populations in Kansas may warrant further scrutiny

From marginal to axial tidal-strait facies in the Early Pleistocene Siderno Strait

This geological guide presents the description of locations associated with a two-day field trip arranged in relation to the 10th International Congress of Tidal Sedimentology (Tidalites), Matera, Italy. The field guide describes sedimentological features of the largest among a series of tectonically controlled tidal straits that dissected the Calabrian Arc in southern Italy during the Early Pleistocene. The WNW-ESE trending, 50x20 km-wide Siderno Strait connected the Tyrrhenian with the Ionian seas. Due to tidal phase opposition between the two basins, continuous water-mass exchanges occurred through the strait, leading to powerful, bi-directionally flowing tidal currents. Sediments filling the Siderno Strait derived from both fluvial supply from the margins and intra-basinal autochthonous carbonate-factory debris. The main objective of the two-day field trip is to guide the visitor through a cross-section of the ancient strait, starting from one of the margins, ending in the deeper axial zone. The focus during the day one is on strait-margin deltaic fluvial-dominated deposits, shed from the tectonically-controlled, northern border and reworked by tidal currents in their distal reaches (delta front). Erosively-based, 4-5 m-thick pebbly-sandstone strata intercalated with 2-3 m-thick tidally-generated cross strata stack into a ca. 170 m-thick succession, exposed in a series of outcrops progressively located down-current with respect to the inferred entry point to the north. The focus of the day two is a ca. 150-190 m-thick succession consisting of cross-stratified mixed (bioclastic-siliciclastic) deposits, forming a series of WNE-ESE-oriented, elongated ridges that accumulated in the south-eastern axial zone of the Siderno Strait. The selected stops offer panoramic views of exceptionally continuous sections and close-up observations, revealing different scales of depositional architectures and a variety of sedimentary structures and trace fossils that record the development of these tidal sand ridges during the strait lifespan. The interplay between the tectonic uplift of a central bedrock sill and a number of syn-sedimentary faults and high-frequency relative sea-level changes (induced by glacio-eustacy and active tectonics) can be deciphered from the architecture of the tidally-generated cross strata composing the main body of the ridges