2,173 research outputs found
Bilateral ischemic lumbosacral plexopathy from chronic aortoiliac occlusion presenting with progressive paraplegia
Spinal cord ischemia is rare but causes significant morbidity and mortality. Spinal cord ischemia has been reported after open and endovascular interventions of the thoracic and abdominal aorta, and, rarely, acute occlusion of aorta from in situ thrombosis or acute embolic occlusion. Acute interruption of the critical blood supply to the spinal cord or root contributes to this devastating neurologic deficit. However, gradually worsening lumbosacral plexopathy and consequent paraplegia related to chronic aortic occlusion is extremely rare. We present a case of a 58-year-old man with progressive lower limb paralysis from atherosclerotic aortoiliac occlusion without history of aortic surgery or evidence of thromboembolism
Mechanistic understanding of perianth traits hindering pollination in Aristolochia contorta Bunge
Insects are vital pollinators for angiosperms, playing a crucial role in their reproductive success and fruit production. Aristolochia contorta is a perennial herbaceous vine that occurs in fragmented populations across East Asia. One notable feature of this plant is its trap flower, which employs a unique mechanism to attract, trap, retain, and release insects, ensuring effective pollination. The presence of this trap flower significantly influences the pollination system of A. contorta. Field surveys and pollination experiments were conducted to understand the processes and effectiveness of its pollination mechanism. It was allogamous and was pollinated by the species from Ceratopogonidae. During the insect attraction stage, 11.57% of the flowers contained insects, primarily Ceratopogonidae spp. Most Ceratopogonidae spp. concentrated in few flowers, indicating that although overall attraction might be modest, specific flowers acted as significant focal points for gathering. Trichomes effectively trapped Ceratopogonidae spp. inside flower tubes. In the retention stage, 26.16% of Ceratopogonidae spp. were loaded with pollen grains, but only 7.91% of those exited the flowers in the release stage. The sticky texture of the perianthâs internal cavity posed challenges during this release, leading to adhesion and clogging of the narrow perianth tube. Consequently, a significant portion of Ceratopogonidae spp. became trapped on the perianth wall and perished. This highlights that despite the significant energy and resources invested in flower development, the perianth contributes to the low pollination effectiveness. This study revealed additive factors with negative effects on pollination, including the densely clustered distribution of its pollinators within only a few flowers, insufficient pollen loading onto pollinators, hindered release of entrapped pollinators due to the perianth adhesive surface, and a high rate of defective pollen grains in A. contorta. These factors account for the observed phenomenon of low fruit set (7.7%) and contribute to the diminished rate of sexual reproduction in A. contorta populations. This might lead the species to heavily rely on asexual reproduction, which could potentially lead to gene erosion within populations. The implications of these findings extend to the ecological and conservation aspects, emphasizing the need to understand and conserve the unique pollination system of A. contorta
Animal Assisted Intervention for Rehabilitation Therapy and Psychotherapy
Animal-assisted Intervention (AAI) is a goal-oriented intervention that intentionally includes or incorporates animals in health, education, and human service for the purpose of therapeutic gains in humans. AAI incorporates human-animal teams in formal human service such as Animal-assisted Therapy (AAT) or Animal-assisted Education (AAE). Animal-assisted Activity (AAA) is the informal AAI often conducted on a volunteer basis by the human-animal team for motivational, educational, and recreational purposes. AAI could be used for rehabilitation therapy and psychotherapy for patients with various symptoms. AAI uses animals, mostly dogs, to aid in healing patients holistically. Dogs have an overwhelming gratitude and exuberance for life and this effect on people is astounding. Furthermore, AAI has been researched and its effectiveness on patientsâ outcomes and healing is documented. With a soaring trend of the incorporation of complementary therapies into the mainstream of therapy and health care, animal-facilitated therapy has become a popular interest for the therapy team to integrate into a patientâs plan of therapy
Molecular Design Approach Managing Molecular Orbital Superposition for High Efficiency without Color Shift in Thermally Activated Delayed Fluorescent Organic Lightâ Emitting Diodes
Molecular design principles of thermally activated delayed fluorescent (TADF) emitters having a high quantum efficiency and a color tuning capability was investigated by synthesizing three TADF emitters with donors at different positions of a benzonitrile acceptor. The position rendering a large overlap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) enhances the quantum efficiency of the TADF emitter. Regarding the orbital overlap, donor attachments at 2â and 6â positions of the benzonitrile were more beneficial than 3â and 5â substitutions. Moreover, an additional attachment of a weak donor at the 4â position further increased the quantum efficiency without decreasing the emission energy. Therefore, the molecular design strategy of substituting strong donors at the positions allowing a large molecular orbital overlap and an extra weak donor is a good approach to achieve both high quantum efficiency and a slightly increased emission energy.Overlap to emit: The substitution of strong donors at the positions rendering a large HOMOâ LUMO overlap and the addition of a weak donor constitute an effective design approach to realize TADF emitters having high efficiency.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147817/1/chem201805616-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147817/2/chem201805616.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147817/3/chem201805616_am.pd
Photo-patternable and transparent films using cellulose nanofibers for stretchable origami electronics
Substantial progress in flexible or stretchable electronics over the past decade has extensively impacted various technologies such as wearable devices, displays and automotive electronics for smart cars. An important challenge is the reliability of these deformable devices under thermal stress. Different coefficients of thermal expansion (CTE) between plastic substrates and the device components, which include multiple inorganic layers of metals or ceramics, induce thermal stress in the devices during fabrication processes or long-term operations with repetitions of thermal cyclic loading-unloading, leading to device failure and reliability degradation. Here, we report an unconventional approach to form photo-patternable, transparent cellulose nanofiber (CNF) hybrid films as flexible and stretchable substrates to improve device reliability using simultaneous electrospinning and spraying. The electrospun polymeric backbones and sprayed CNF fillers enable the resulting hybrid structure to be photolithographically patternable as a negative photoresist and thermally and mechanically stable, presenting outstanding optical transparency and low CTE. We also formed stretchable origami substrates using the CNF hybrid that are composed of rigid support fixtures and elastomeric joints, exploiting the photo-patternability. A demonstration of transparent organic light-emitting diodes and touchscreen panels on the hybrid film suggests its potential for use in next-generation electronics.ope
Primary Extracranial Meningioma Presenting as a Cheek Mass
Meningioma is well known as common disease of the central nervous system, whereas primary extracranial meningioma is rare, representing 1% to 2% of all meningiomas. We have experienced a case of primary extracranial meningioma presenting as a right cheek mass. The tumor was completely excised via a right lateral rhinotomy incision. Histopathologic examination confirmed the diagnosis of primary extracranial meningioma
Nearly 100% Horizontal Dipole Orientation and Upconversion Efficiency in Blue Thermally Activated Delayed Fluorescent Emitters
The relationship between anisotropic orientation and molecular structure of thermally activated delayed fluorescent (TADF)âbased organic light emitting devices (OLEDs) is studied using TADF emitters with carbazole, biscarbazole, and triscarbazole donor units. The bicarbazole and triscarbazole donors are more effective than the carbazole donor in driving the anisotropic orientation of the TADF molecules. A nearâperfect inâplane orientation of the TADF dipole moment is demonstrated using the triscarbazole donor. In addition, the triscarbazole donor based OLED shows high photoluminescence quantum yield and an upconversion efficiency close to 100%. As a consequence, an external quantum efficiency >30% is obtained.A systematic study correlating donor structure with horizontal dipole orientation of blue triscarbazole thermally activated delayed fluorescent (TADF) emitters shows an exceptionally high horizontal dipole orientation of 95%. The dipole orientation and high photoluminescence quantum yield result in an external quantum efficiency >30% in organic lightâemitting diodes employing these TADF emitters.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145231/1/adom201701340.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145231/2/adom201701340_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145231/3/adom201701340-sup-0001-S1.pd
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