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31.
Investigation of an extract from the marine cyanobacterium Lyngbya semiplena, collected in Tumon Bay, Guam, led to the identification of three new cyclodepsipeptides, lyngbyastatins 8–10 (1–3). The structures of 1–3 were determined by NMR, MS, ESIMS fragmentation and chemical degradation. Compounds 1–3 are closely related to lyngbyastatins 4–7. Like the latter compounds, we found 1–3 to inhibit porcine pancreatic elastase, with IC50 values of 123 nM, 210 nM and 120 nM, respectively. 相似文献
32.
M. Meron J. Tsipris Valerie Orlov V. Alchanatis Yafit Cohen 《Precision Agriculture》2010,11(2):148-162
Variable-rate irrigation by machines or solid set systems has become technically feasible, however mapping crop water status
is necessary to match irrigation quantities to site-specific crop water demands. Remote thermal sensing can provide such maps
in sufficient detail and in a timely way. In a set of aerial and ground scans at the Hula Valley, Israel, digital crop water
stress maps were generated using geo-referenced high-resolution thermal imagery and artificial reference surfaces. Canopy-related
pixels were separated from those of the soil by upper and lower thresholds related to air temperature, and canopy temperatures
were calculated from the coldest 33% of the pixel histogram. Artificial surfaces that had been wetted provided reference temperatures
for the crop water stress index (CWSI) normalized to ambient conditions. Leaf water potentials of cotton were related linearly
to CWSI values with R
2 = 0.816. Maps of crop stress level generated from aerial scans of cotton, process tomatoes and peanut fields corresponded
well with both ground-based observations by the farm operators and irrigation history. Numeric quantification of stress levels
was provided to support decisions to divide fields into sections for spatially variable irrigation scheduling. 相似文献
33.
In a histological study comparing tuber resistance of potato clone B7200-33 and susceptible variety “Russet Burbank” toFusarium roseum ‘Sambucinum’, the formation of suberin and wound periderm was found to be an important resistance mechanism. In B7200-33 tubers a continuous suberin layer was formed whereas in ‘Russet Burbank’ tubers the suberin was formed in clumps so that the pathogen easily could invade the tissue between the clumps but not through a continuous layer. Wound periderm also was formed at a more rapid rate in B7200-33 than in ‘Russet Burbank’ tubers thereby “walling off” the pathogen and reducing decay. 相似文献
34.
Valerie F. Samii DVM David S. Biller DVM Philip D. Koblik DVM MS 《Veterinary radiology & ultrasound》1999,40(5):486-490
Magnetic resonance images of two adult domestic short-haired cats were obtained with a whole body scanner. Images of the abdomen were compared with cross-sectional anatomy cadaver specimens from the same two cats. Anatomic structures were first identified on the cadaver specimens with the aid of anatomy texts and references and were then identified and labeled on the magnetic resonance images. Results from this project provide an atlas of normal cross-sectional MRI anatomy of the feline abdomen. 相似文献
35.
Valerie M. Sadler DVM Erik R. Wisner DVM James T. Robertson DVM Valentine S. Moses DVM 《Veterinary radiology & ultrasound》1999,40(3):259-261
Congenital anomalies of the equine salivary glands and their ductal systems are rare. In man, parotid duct atresia is thought to be due to a congenital malformation of the first branchial arch. One horse with unilateral parotid salivary duct atresia is described. Imaging modalities available for accurate diagnosis, and treatment options, are reviewed. 相似文献
36.
Susan J. Holcombe VMD MS Alicia L. Bertone DVM PhD David S. Biller DVM Valerie Haider DVM 《Veterinary radiology & ultrasound》1995,36(2):119-125
The purpose of this study was to define normal gross anatomic structures in the equine stifle with magnetic resonance images. Magnetic resonance (MR) images were made in sagittal, 15° supinated, transverse, and dorsal planes of two equine stifles. The MR images were scrutinized by comparing MR images to dissection specimens and frozen cross sections of stifle joints. Sagittal and 15° supinated images were the most valuable in assessing articular cartilage, subchondral bone, and soft tissue structures within the joint. Cranial and caudal cruciate ligaments, medial and lateral menisci, meniscotibial and meniscofemoral ligaments, long digital extensor tendon, and patellar ligaments were easily evaluated. MR images provided substantially more gross anatomical information than the currently available imaging modalities. 相似文献
37.
38.
Sabine Riesen DR MED VET Valerie Schmid DR MED VET Lorrie Gaschen DVM DR MED VET Andre Busato DR MED VET MSC Johann Lang PD DR MED VET 《Veterinary radiology & ultrasound》2002,43(6):554-560
The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog. 相似文献
39.
40.
Valerie J. Stull Mukata Wamulume Mwangala I. Mwalukanga Alisad Banda Rachel S. Bergmans Michael M. Bell 《Agriculture and Human Values》2018,35(4):867-883
Entomophagy—the practice of eating insects—has been touted as a means to combat undernutrition and food insecurity globally. Insects offer a nutritious, environmentally friendly alternative to resource-intensive livestock. But the benefits of edible insects cannot be realized if people do not choose to eat them. We therefore examine the social acceptability of edible insects in rural Zambia, where entomophagy is common but underexplored. Through a village case study, we show that edible insects are not valued equally, are understood socially, and seem to reflect and reinforce social values. We utilize grounded theory and ethnographic methods, including semi-structured interviews, focus groups, and observation to examine collective entomophagy beliefs. While we expected to see differentiation in perceptions across groups based on kinship, we demonstrate that social values related to class, urbanism, gender, and age emerge as more germane explanations for entomophagy perceptions, reflecting their social weight. By expanding on current apperception of entomophagy behavior, our findings inform future research and efforts to promote entomophagy through minilivestock farming. Systems designed to maximize output, minimize labor, and highlight benefits are more likely to be widely accepted. We do not anticipate tribal association will be the primary limitation on minilivestock adoption in this context. 相似文献