701 research outputs found
Documenting Bombus nevadensis in Minnesota, with Some Notes on Discerning It from B. auricomus (Hymenoptera: Apidae)
In the face of well-documented declines in multiple bumblebee species, it is important to accurately identify species and properly delineate species ranges. Here, we document the range of Bombus auricomus (Robertson) and B. nevadensis Cresson in Minnesota, with particular reference to the unexpected discovery of B. nevadensis in St. Paul. We clarify the relative ranges of these two species and provide additional information on how to reliably identify them in Minnesota using color patterns and morphology, including differences in male genitalia. Our results support the consensus that B. auricomus and B. nevadensis are distinct species. Community science records were integral to fully documenting the range of B. nevadensis in Minnesota. Our findings demonstrate the value of community science data, though it highlights the need for experts to check the data and to be mindful of biases in observations around population centers
Spectrum of an oscillator with jumping frequency and the interference of partial susceptibilities
We study an underdamped oscillator with shot-noise frequency fluctuations.
The oscillator spectrum is determined by the interference of the
susceptibilities for different eigenfrequencies. Depending on the parameters,
it has a fine structure or displays a single asymmetric peak. For
nano-mechanical resonators with a fluctuating number of attached molecules, the
spectrum is found in a simple analytical form. The results bear on various
types of systems where the reciprocal correlation time of frequency
fluctuations can be comparable to the typical frequency jumps
First Records of the Adventive Pseudoanthidium nanum (Mocsáry) (Hymenoptera: Megachilidae) in Illinois and Minnesota, with Notes on its Identification and Taxonomy
We report the first records of Pseudoanthidium nanum (Mocsáry) in Illinois and Minnesota in 2016 and 2018, respectively. This represents a relatively rapid expansion since P. nanum was first detected in New Jersey in 2008. In order to help monitor the spread of this bee, we provide information on how to identify P. nanum and provide images of the general habitus, diagnostic features, and male genitalia. Finally, we confirm the taxonomic identity of P. nanum in the United States and highlight potential impacts on native anthidiines
Megachile (Megachile) montivaga (Hymenoptera: Megachilidae) nesting in live thistle (Asteraceae: Cirsium)
Although Megachile Latreille (leafcutter bees) are well known for their diverse nesting habits, records of the genus nesting in live plants are rare. Here, we report the widespread Megachile (Megachile) montivaga Cresson nesting in live thistle (Cirsium neomexicanum Gray), the first explicit record of this behavior in the Nearctic
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
Reinstatement of Andrena vernalis Mitchell (Hymenoptera: Andrenidae) from synonymy with A. ziziae Robertson
Andrena (Micrandrena) ziziae Robertson, 1891 (Andrenidae) is a well-known species found in a variety of habitats in the eastern and central United States and adjacent southern Canada. Andrena (Micrandrena) vernalis Mitchell, 1960 was described from five female specimens in the eastern United States and was synonymized with A. ziziae by Ribble in 1968. Recently collected specimens from throughout Minnesota have revealed that A. ziziae sensu Ribble is actually two species, one of which matches A. vernalis. Here, we reinstate A. vernalis as a valid species and describe the previously unknown male. We provide diagnostic characters that separate A. ziziae and A. vernalis, as well as data on the geographic range and floral preferences of both species in Minnesota. Andrena vernalis appears to be restricted to high-quality remnant habitats, making it a species of potential conservation concern. These changes will require that previous work on A. ziziae be revisited to determine if A. vernalis is also present
Does malnutrition influence outcome in children undergoing congenital heart surgery in a developing country?
Background Most children undergoing cardiac surgery for
congenital heart disease (CHD) in developing countries are
malnourished. Malnutrition is known as a co-morbidity factor
that might predict and influence outcomes after surgery.
Objectives To evaluate the effect of malnutrition and other
associated risk factors on post-operative outcomes in children
with CHDs underwent cardiac surgery.
Methods We conducted a retrospective cohort study in a single
center tertiary pediatric cardiac intensive care unit (PCICU)
in Indonesia. Our cohort included all children between 5 and
36 months of age undergoing congenital heart surgery with
cardiopulmonary bypass from November 2011 until February
2014. Outcomes measured were the length of intubation and the
length of ICU stay. Variables for potential influence investigated
were the nutritional status, age, gender, type of cardiac anomaly
(acyanotic vs. cyanotic), Aristotle score, cardiopulmonary bypass
time, aortic cross-clamp time, and Pediatric Risk of Mortality
(PRISM) III score.
Results Out of 249 patients included, 147 (59%) showed
malnourishment on admission. Malnourished patients were
significantly younger in age, presented with an acyanotic heart
defects, and had higher PRISM III score. Additionally, they also
had a longer mechanical ventilation time and ICU stay than
those with a normal nutritional status. After adjusting for various
variables using a multiple logistic regression model it could be
demonstrated that a higher Z-score for weight to age was a
significant protective factor for the intubation time of more than
29 hours with an odds ratio of 0.66 (95% CI 0.48 to 0.92, P =
0.012). Non-malnourished patients had a 49% significantly higher
chance for extubation with a hazard ratio of 1.49 (95% CI 1.12
to 1.99, P= 0.007).
Conclusion Malnourishment is clearly associated in a linear
fashion with longer mechanical ventilation and ICU stay. As one of
significant and potentially treatable co-morbidity factors, prevention
of malnourishment by early diagnosis and optimal timing for surgery
is important
MuRF1 mono-ubiquitinates TRα to inhibit T3-induced cardiac hypertrophy in vivo
Thyroid hormone (TH) is recognized for its role in cellular metabolism and growth and participates in homeostasis of the heart. T3 activates pro-survival pathways including Akt and mTOR. Treatment with T3 after myocardial infarction is cardioprotective and promotes elements of physiological hypertrophic response after cardiac injury. Although T3 is known to benefit the heart, very little about its regulation at the molecular level has been described to date. The ubiquitin proteasome system (UPS) regulates nuclear hormone receptors such as estrogen, progesterone, androgen, and glucocorticoid receptors by both degradatory and non-degradatory mechanisms. However, how the UPS regulates T3-mediated activity is not well understood. In this study, we aim to determine the role of the muscle-specific ubiquitin ligase muscle ring finger-1 (MuRF1) in regulating T3-induced cardiomyocyte growth. An increase in MuRF1 expression inhibits T3-induced physiological cardiac hypertrophy, whereas a decrease in MuRF1 expression enhances T3’s activity both in vitro and in cardiomyocytes in vivo. MuRF1 interacts directly with TRα to inhibit its activity by posttranslational ubiquitination in a non-canonical manner. We then demonstrated that a nuclear localization apparatus that regulates/inhibits nuclear receptors by sequestering them within a subcompartment of the nucleus was necessary for MuRF1 to inhibit T3 activity. This work implicates a novel mechanism that enhances the beneficial T3 activity specifically within the heart, thereby offering a potential target to enhance cardiac T3 activity in an organ-specific manner
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