2,316 research outputs found
Scanning electron microscopic studies on tongue of open-nesting honey bees Apis dorsata F. and Apis florea F. (Hymenoptera: Apidae)
Taste stimuli play vital role in the life of honey bees. Sensory structures observed on tongue of the honey bees with the help of Scanning electron microscopy (SEM) have become an important tool in analyzing honey bee biodiversity which offers an advanced diagnostic tool to study honey bee biogeography and determine adaptive variations to native flora. Tongue of honey bees present a high geographic variability in regard to the floral resources visited by the bees. The present study has determined to determine differences in the tongue ofopen-nesting bees by scanning electron microscopy of Apis dorsata and Apis florea. The two bees showed distinct morphological variations with respect to the lapping and sucking apparatus. It was observed that the ridges on the proximal region exhibited rough surface on A.dorsata whereas spinous in case of A.florea. Moreover, the arrangement of hair in the middle part of the tongue also differed in the two species. The shape of flabellum differed in the two species reason being the influence of native flora. It was observed that the shape of flabellum was oval in A.dorsata whereas in A.florea it was triangular. These differences indicated for the role of native flora and honey bee biodiversity
Ultramorphology of antennal sensilla of open-nesting honey bees Apis florea F. and Apis dorsata F. (Hymenoptera: Apidae)
Antenna of honey bees is geniculate and has been known to possess a wide variety of sensilla. The sensilla are sensitive to odor, temperature, humidity, air pressure and gustatory stimuli. In the present investigation, ultrastructural study on the antenna of the two open-nesting worker honey bees- Apis florea F. - the dwarf honey bee and A. dorsata F. - the giant honey showed considerable amount of variation in the types and distribution pattern of sensilla in the two species. The antennal form as well as the sensilla arrangement has been suggested to be adapted to the pheromone perception need of regarding a particular species
Calicovesicostomy for ureteropelvic junction obstruction in a solitary ectopic pelvic kidney
A solitary dysmorphic ectopic kidney is an uncommon congenital abnormality. This anomaly may be associated with ureteropelvic junction obstruction causing hydronephrosis and parenchymal thinning. We report such a case with non-dependent posteriorly placed pelvis in a pelvic kidney and its management. The perioperative results were satisfactory. This seems to be the first such case report of a calicovesicostomy used as a salvage procedure for an ectopic solitary kidney
Squamous Cell Carcinoma in a Heel Ulcer in a Patient With Diabetes
A technique for measuring B-H curves of grain-oriented silicon steel along arbitrary directions has been developed. As the control of waveform is not necessary in this technique, it is possible to measure B-H curves up to high flux densities which are required for calculating flux distribution using the finite element method</p
Multi-Robot-Assisted Human Crowd Evacuation using Navigation Velocity Fields
This work studies a robot-assisted crowd evacuation problem where we control
a small group of robots to guide a large human crowd to safe locations. The
challenge lies in how to model human-robot interactions and design robot
controls to indirectly control a human population that significantly outnumbers
the robots. To address the challenge, we treat the crowd as a continuum and
formulate the evacuation objective as driving the crowd density to target
locations. We propose a novel mean-field model which consists of a family of
microscopic equations that explicitly model how human motions are locally
guided by the robots and an associated macroscopic equation that describes how
the crowd density is controlled by the navigation velocity fields generated by
all robots. Then, we design density feedback controllers for the robots to
dynamically adjust their states such that the generated navigation velocity
fields drive the crowd density to a target density. Stability guarantees of the
proposed controllers are proven. Agent-based simulations are included to
evaluate the proposed evacuation algorithms
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Search for the Higgs boson decays H -> ee and H -> eμ in pp collisions at root s=13 TeV with the ATLAS detector
Searches for the Higgs boson decays H -> ee and H -> e mu are performed using data corresponding to an integrated luminosity of 139 fb(-1) collected with the ATLAS detector in pp collisions at root s = 13 TeV at the LHC. No significant signals are observed, in agreement with the Standard Model expectation. For a Higgs boson mass of 125 GeV, the observed (expected) upper limit at the 95% confidence level on the branching fraction B(H -> ee) is 3.6 x 10(-4) (3.5 x 10(-4)) and on B(H -> e mu) is 6.2 x 10(-5) (5.9 x 10(-5)). These results represent improvements by factors of about five and six on the previous best limits on B(H -> ee) and B(H -> e mu) respectively. (C) 2019 The Author. Published by Elsevier B.V.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Chilling stress effects on reproductive biology of chickpea
Chickpea is sensitive to chilling temperatures (<10°C),
especially at its reproductive phase leading to floral
abortion. The exact causes of reproductive failures are
not fully understood. In the present study, we assessed the
cold-induced damage to development and functioning of
male and female components by growing an early
flowering chickpea genotype ICCV 96029 under warm
conditions of the glasshouse (control; average maximum
and minimum temperature ≥28/15°C) as well as under
cold conditions of the field (average maximum and
minimum temperature ≤20/10°C during reproductive
phase). Low temperature of the field environment
restricted the vegetative growth and delayed all the
phenological stages in comparison to control plants.
Apart from this, it led to some vegetative aberrations like
chlorosis, necrosis of leaf tips and curling of whole leaf.
The damage to reproductive stage involved abscission of
juvenile buds and flowers and abortion of pods. On the
whole, pollen development at young microspore stage
appeared to be severely affected in stressed conditions
compared to the control conditions. Pollen viability was
suppressed during stressed conditions (60%) compared
to normal plants (95%). Stigma receptivity, in vivo pollen
germination and pollen tube growth were inhibited in the
stressed plants. Fluorescent studies showed that the
stigma either did not show any pollen load or pollen
grains did not germinate on its surface in stressed plants.
Even when the pollen grains germinated, the pollen tubes
rarely grew beyond the proximal region of the style;
mostly the pollen tubes were impaired in their growth and
did not reach the ovules leading to failure in fertilization.
The egg and secondary nucleus in such ovules ultimately
disintegrated without fertilizing and hence no seed
formation occurred
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