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81.
The ability to recognize people by their voice is an important social behavior. Individuals differ in how they pronounce words, and listeners may take advantage of language-specific knowledge of speech phonology to facilitate recognizing voices. Impaired phonological processing is characteristic of dyslexia and thought to be a basis for difficulty in learning to read. We tested voice-recognition abilities of dyslexic and control listeners for voices speaking listeners' native language or an unfamiliar language. Individuals with dyslexia exhibited impaired voice-recognition abilities compared with controls only for voices speaking their native language. These results demonstrate the importance of linguistic representations for voice recognition. Humans appear to identify voices by making comparisons between talkers' pronunciations of words and listeners' stored abstract representations of the sounds in those words. 相似文献
82.
Lima MD Fang S Lepró X Lewis C Ovalle-Robles R Carretero-González J Castillo-Martínez E Kozlov ME Oh J Rawat N Haines CS Haque MH Aare V Stoughton S Zakhidov AA Baughman RH 《Science (New York, N.Y.)》2011,331(6013):51-55
Multifunctional applications of textiles have been limited by the inability to spin important materials into yarns. Generically applicable methods are demonstrated for producing weavable yarns comprising up to 95 weight percent of otherwise unspinnable particulate or nanofiber powders that remain highly functional. Scrolled 50-nanometer-thick carbon nanotube sheets confine these powders in the galleries of irregular scroll sacks whose observed complex structures are related to twist-dependent extension of Archimedean spirals, Fermat spirals, or spiral pairs into scrolls. The strength and electronic connectivity of a small weight fraction of scrolled carbon nanotube sheet enables yarn weaving, sewing, knotting, braiding, and charge collection. This technology is used to make yarns of superconductors, lithium-ion battery materials, graphene ribbons, catalytic nanofibers for fuel cells, and titanium dioxide for photocatalysis. 相似文献
83.
Stephanie Kramer-Schadt Tobias S. Kaiser Karin Frank Thorsten Wiegand 《Landscape Ecology》2011,26(4):501-513
With habitat loss and fragmentation having become two of the major threats to the viability of species, the question of how
to manage landscapes for species conservation has attracted much attention. In this context, the planning of stepping stones
has been proposed to increase connectivity in fragmented landscapes. We present a simulation study with a neutral landscape
approach to assess the effects of stepping stones on colonization success. To that end, we used a spatially explicit, calibrated
population model of the European lynx (Lynx lynx) coupled with structured landscapes, in which we could control the landscape parameters of dispersal habitat coverage and
contagion, as well as the number and size of stepping stones available for breeding. In general, we found that colonization
success increased with increasing habitat coverage but decreased with increasing habitat contagion, while the introduction
of stepping stones had significant effects in critical situations. Especially at low to medium dispersal habitat coverage
and high disperser mortality, stepping stones had a positive effect on colonization success when they were large enough to
produce new dispersers, but negative effects when they were small and located in a way that dispersers would be distracted
from more suitable breeding habitat patches. The latter clearly constituted a shading effect and argues for a thorough consideration
of the trade-offs related to stepping stone size and location when implementing stepping stones as a conservation measure,
especially when the number of individuals of conservation concern is low. 相似文献
84.
85.
Pfau T Garland de Rivaz A Brighton S Weller R 《Veterinary journal (London, England : 1997)》2011,190(2):278-283
A recent survey reported an increased risk of injury in dogs participating in agility, a competitive canine sport involving different jumping activities. The aim of this study was to quantify the kinetic parameters during jump landing for commonly used obstacle types. It was hypothesised that with increasing obstacle height, the vertical force and vertical and accelerative horizontal impulse will increase as a result of a lengthened aerial phase, a more acute landing angle and the need to convert potential into forwards kinetic energy. Simultaneous kinetic and kinematic data were recorded from 11 competition agility dogs jumping over obstacle combinations of different height and inter-obstacle distance. Speed and landing angle of the second of the two consecutive jumps were successfully controlled by obstacle height and distance between obstacles. Statistical analysis showed differences between obstacles for peak vertical force, vertical impulse and accelerative horizontal impulse (increasing values with more acute landing angles). Extremely high peak vertical force was observed in the forelimbs (4.5 times bodyweight) when landing from a hurdle jump at high speed. Further detailed studies into the consequences for internal limb structures are warranted in order to clarify how this might be related to injury. 相似文献
86.
Minor KM Patterson EE Keating MK Gross SD Ekenstedt KJ Taylor SM Mickelson JR 《Veterinary journal (London, England : 1997)》2011,189(2):214-219
The impact of the mutation causing dynamin 1 (DNM1)-associated exercise-induced collapse (d-EIC) was determined in a retrospective genetic survey. The frequency of DNM1 mutant allele carriers in Labrador retrievers from conformation show, field trial/hunt test, pet or service lines ranged from 17.9% to 38.0% and the frequency of homozygous mutant (EE genotype) individuals ranged from 1.8% to 13.6%; 83.6% of these EE Labradors were reported to have collapsed by 4 years of age. DNM1 mutation carriers and EE dogs with a collapse phenotype were also detected in Chesapeake Bay retrievers, Curly-coated retrievers, Boykin spaniels, Pembroke Welsh corgis and mixed breed dogs thought to be Labrador retriever crosses. The DNM1 mutation was not identified in Golden, Flat-coated, or Nova Scotia duck tolling retrievers, or 15 other non-retrieving breeds. Veterinarians and breeders should be aware that the DNM1 EE genotype is not completely penetrant and that d-EIC is a widespread health concern in several very popular breeds, as well as breeds whose genetic similarity to retrievers is not obvious. 相似文献
87.
Stephanie J. Brodrick M. K. Sakala Kenneth E. Giller 《Biology and Fertility of Soils》1992,13(1):39-44
Summary Plants grown from seed with high (1.5–7.3 g Mo seed-1) and low (0.07–1.4 g Mo seed-1) Mo contents were grown in the presence and absence of Mo in growth media (perlite) or in a flowing-solution culture, in a controlled environment. Neither the high (1.5 g Mo seed-1) nor the low (0.1 g Mo seed-1) Mo content in seed from a small-seeded genotype (BAT 1297) was able to prevent Mo deficiency (reduced shoot, root and nodule dry weight, N2 fixation and seed production) in growth media without an external supply of Mo, whereas both the high (7.3 g Mo seed-1) and the low (0.07 g Mo seed-1) contents in seed were able to prevent Mo deficiency in a large-seeded genotype (Canadian Wonder). Responses to Mo treatment by the Two genotypes were inconsistent between the growth media and solution culture experiments. Seed with a large Mo content (3.5 g Mo seed-1) from the Canadian Wonder genotype was unable to prevent Mo deficiency (reduced shoot and nodule dry weight and N2-fixation) in a solution culture without an external source of Mo, whereas both the large (1.7 g Mo seed-1) and the small (0.13 g Mo seed-1) contents in seed prevented a deficiency in BAT 1297. Growing plants from seed with a small Mo content, without additional Mo, reduced the seed Mo content by 83–85% and seed production by up to 38% in both genotypes. Changes in seed size and increases in shoot, root and nodule dry weight occurred, but varied with the genotype and growth conditions. These effects were also observed in some cases where plants were grown with additional Mo, demonstrating that the amount of Mo in the seed sown can influence plant nutrition irrespective of the external Mo supply. Nodule dry weight, total N content of shoots and seed production were improved by using seed with a small Mo content (1.64–3.57 g Mo seed-1) on acid tropical soils in Northern Zambia. Plants of both the large- and small-seeded genotypes grown from seed with a small Mo content (<1.41 g Mo seed-1) had a smaller nodule weight, accumulated less N and produced less seed. The viability of seed with a small Mo content was lower (germination up to 50% less) than that of seed with a large Mo content. 相似文献
88.
Judith A. Hudson DVM PhD Susan T. Finn-Bodner DVM MS Joan R. Coates DVM Donald C. Sorjonen DVM MS Stephen T. Simpson DVM MS James C. Wright DVM PhD Jan E. Steiss DVM PhD Nancy R. Cox DVM PhD Dana M. Vaughn DVM PhD Starr C. Miller BS Scott A. Brown DVM PhD Phillip D. Garrett DVM MS 《Veterinary radiology & ultrasound》1995,36(6):542-547
Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06. 相似文献
89.
GARY W. ELLISON DVM MS Diplomate ACVS JAMIE R. BELLAH DVM Diplomate ACVS W. PRESTON STUBBS DVM JAMES VAN GILDER BS 《Veterinary surgery : VS》1995,24(2):140-147
Excision of perianal fistulas using a 1.064 micron wavelength neodymium:yttrium aluminum garnet (ND:YAG) contact tipped laser with primary wound closure was used to treat 20 dogs with perianal fistulas. Overall, 19 of 20 (95%) dogs had resolution of fistulas after one or more ND:YAG treatments. The period of resolution ranged from 10 to 42 months with a mean of 22.9 months. Sixteen of 20 (80%) dogs had resolved fistulas after one laser excision. Three of the four recurrences underwent additional laser treatments with successful results. The total number of laser procedures ranged from one to three with a mean of 1.2 procedures. Postoperatively, anal tone as judged by digital rectal examination was reduced in about 60% of the cases, but clinical evidence of fecal incontinence only occurred in four of 20 cases. This was managed effectively with diet modification. The tendency toward loss of anal tone or fecal incontinence depended on the severity of preexisting anal stenosis. On a client survey, 19 of 20 owners believed that their animals experienced less pain during defecation after surgery and rated the results as excellent or good. The overall success rate using ND:YAG laser excision compared very favorably with previously reported studies of other methods of treatment for perianal fistulas in dogs. 相似文献
90.
ANDRÉ DESROCHERS DMV MS GUY ST-JEAN DMV MS Diplomate ACVS DAVID E. ANDERSON DVM MS Diplomate ACVS DONNA P. ROGERS BS M.M. CHENGAPPA BVSc PhD Diplomate ACVM 《Veterinary surgery : VS》1996,25(4):336-341
One hundred seventeen cattle that had undergone surgery were assigned randomly to two preoperative skin preparation protocols. Group 1 (60 animals) skin preparation was with povidone-iodine soap and isopropyl alcohol, whereas group 2 (57 animals) had skin preparation with chlorhexidine gluconate and isopropyl alcohol. Quantitative microbial culture plates were used to estimate the number of colony forming units (CFUs) before skin preparation (prescrub), after skin preparation (postscrub), after surgery (postoperative), and in room air (environment). A significant decrease in CFU occurred postscrub for both skin preparations ( P <.05). Chlorhexidine and alcohol preparation resulted in significantly fewer CFUs (LSMean ± SE = 2.79 CFU ± 1.74) and a greater percentage reduction in CFUs (98.64%± 2.01) postscrub than povidone and alcohol (LSMean ± SE = 10.27 CFUs ± 1.51, 93.29%± 1.85); ( P <.005). Group 2 had a significantly higher frequency of negative cultures postscrub (49.1%) compared with group 1 (18.3%) ( P <.001). The number of postoperative CFUs were not significantly different between the two treatment groups. Wound infection frequency for clean surgical procedures was not significantly different between the two skin preparation protocols (group 1 = 9.8%, group 2 = 10.7%), however, infection frequency was significantly higher for surgical procedures with a ventral abdominal approach (5 of 14, 35.7%), compared with a flank approach (1 of 41, 2.4%) or other approaches (orthopedic procedures) (1 of 16, 6.3%) ( P <.05). Both skin preparation protocols were effective and safe in decreasing the skin microflora population of cattle before surgery and although preparation with chlorhexidine gluconate and alcohol resulted in less CFUs immediafly postscrub, the frequency of surgical wound infection was similar for both protocols. 相似文献