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71.
Ishay JS Plotkin M Ermakov NY Volynchik S Barkay Z Bergman DJ 《Journal of electron microscopy》2006,55(1):41-49
In the social wasps Vespa orientalis and Paravespula germanica (Hymenoptera, Vespinae), a thermogenic center has been found in the dorsal part of the first thoracic segment. The temperature in this region of the prothorax is higher by 6-9 degrees C than that at the tip of the abdomen, and this in actively flying hornets outside the nest (workers, males or queens) as well as in hornets inside the nest that attend to the brood in the combs. On viewing the region from the outside, one discerns a canal or rather a fissure in the cuticle, which commences at the center of the dorsal surface of the prothorax and extends till the mesothorax. Thus the length of this canal or fissure is approximately 5-7 mm and it is seen to contain numerous thin hairs whose shape varies from that of the hairs alongside the structure. Beneath the cuticle in this region there are dorsoventral as well as longitudinal muscles in abundance, much the same as the musculature in the remaining thoracic segments (i.e. the meso- and metathorax), which activate the two pairs of wings. The canal-bearing segment is of course devoid of wings, and its dorsoventral muscles are attached to the cuticle, which in this region resembles a bowl harboring several layers of epithelium that boasts numerous butterfly-shaped tracheal branches. Additionally there are layers that display lymph-filled spaces and also perforated layers and depressions, and beneath all these is a lace-like layer that also coats the cuticle's hollows. Underneath the cuticle proper, there are numerous large mitochondria and tracheae, which occupy a considerable part of the cuticular epithelium surface. These abundant mitochondria are, most probably, the main element of heat production in the thermogenic center. 相似文献
72.
Tunable Nanoparticle and Cell Assembly Using Combined Self‐Powered Microfluidics and Microcontact Printing 下载免费PDF全文
Cyrille Hamon Malou Henriksen‐Lacey Andrea La Porta Melania Rosique Judith Langer Leonardo Scarabelli Ana Belén Serrano Montes Guillermo González‐Rubio Marian M. de Pancorbo Luis M. Liz‐Marzán Lourdes Basabe‐Desmonts 《Advanced functional materials》2016,26(44):8053-8061
The combination of cell microenvironment control and real‐time monitoring of cell signaling events can provide key biological information. Through precise multipatterning of gold nanoparticles (GNPs) around cells, sensing and actuating elements can be introduced in the cells' microenviroment, providing a powerful substrate for cell studies. In this work, a combination of techniques are implemented to engineer complex substrates for cell studies. Alternating GNPs and bioactive areas are created with micrometer separation by means of a combination of vacumm soft‐lithography of GNPs and protein microcontract printing. Instead of conventional microfluidics that need syringe pumps to flow liquid in the microchannels, degas driven flow is used to fill dead‐end channels with GNP solutions, rendering the fabrication process straightforward and accessible. This new combined technique is called Printing and Vacuum lithography (PnV lithography). By using different GNPs with various organic coating ligands, different macroscale patterns are obtained, such as wires, supercrystals, and uniformly spread nanoparticle layers that can find different applications depending on the need of the user. The application of the system is tested to pattern a range of mammalian cell lines and obtain readouts on cell viability, cell morphology, and the presence of cell adhesive proteins. 相似文献
73.
Bohdan Schneider Jan Štokr Pavel Schmidt Marian Mihailov Stoil Dirlikov Nadezhda Peeva 《Polymer》1979,20(6):705-712
Infrared and Raman spectra of atactic PMMA and infrared spectra of stereoregular PMMA and of its four deuterated derivatives , were measured. They were used to assign the bands of stretching and deformation vibrations of CH2, CCH3 and OCH3 groups in the infrared and Raman spectra and to discuss the effect of stereoregularity on these bands in the infrared spectra. 相似文献
74.
Investigated the relationships among magazine exposure, self-objectification, body shape dissatisfaction, and eating disorder symptomatology in 150 men and women (aged 18-42 yrs). Women reading beauty magazines and men reading fitness magazines internalized societal ideals (internalization). For women, beauty magazines predicted self-objectification, mediated by internalization. For men, only internalization predicted self-objectification. For men, fitness magazines predicted body shape dissatisfaction, mediated by internalization. For women, only internalization predicted body shape dissatisfaction. Reading magazines also predicted eating problems for men and women, for women this was mediated by internalization. Findings suggest that magazine reading is related to concerns with physical appearance and eating behaviors. Many of the relationships previously found for women are similar for men. A sociocultural model is used to explain these results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Lilah Halbkat Kun Luan Grayson Cave Marian McCord Michael Roe Emiel DenHartog 《纺织学会志》2013,104(10):1468-1474
Mosquito resistant apparel has become increasingly sought-after due to the rise in vector-borne illnesses such as the Zika Virus, Malaria, and Dengue Fever. Botanical insect repellents have been introduced to the market for consumers that desire a natural solution involving no pesticides or added chemicals. Fabric swatches consisting of 80% nylon and 20% elastane were separately treated with an organic repellent using a patented nonwoven vessel. The fabrics were then tested for effectiveness in repelling the mosquito Aedes aegypti using an arm-in-cage assay, the most commonly used method for mosquito repellents. The repellents were also evaluated and rated by study participants according to their preference for the appeal of the scent. The treatment method is user-friendly, enabling consumers to treat their clothing with an organic insect repellent as opposed to applying a synthetic chemical to their clothing and skin. The infused fabrics showed to be effective at repelling mosquitoes for up to 8 h after repellent infusion. 相似文献
76.
Marian D. Goebes Alexandria B. Boehm Lynn M. Hildemann 《Aerosol science and technology》2013,47(3):352-363
Aspergillus is a mold genus that can cause allergies, asthma, and pulmonary infections in sensitive people; its particles are common in indoor air. Two potential contributors to indoor Aspergillus particles were examined in this field study: human activity (walking over carpet), and outdoor Aspergillus concentrations. Filtered air samples were collected outdoors and inside two carpeted hallways in public buildings, while measuring indoor foot traffic. Aspergillus concentrations were analyzed using quantitative Polymerase Chain Reaction (qPCR). A bivariate model was used to predict indoor Aspergillus concentrations based on foot traffic and outdoor Aspergillus concentrations. For 3 of 4 scenarios, most of the variation in indoor Aspergillus could be explained by the combined effect of outdoor Aspergillus concentrations and foot traffic, with particularly strong correlations during peak traffic times. In addition, indoor Aspergillus was significantly associated with outdoor Aspergillus in 2 of 4 scenarios, and with foot traffic in 2 of 4 scenarios. For 2 of 3 sampling campaigns, Aspergillus did not have a significant association either with gravimetric particulate matter ≤5 μm (PM5), or with optically measured PM of 0.75–1 μm, 1–2 μm, 2–3.5 μm, or 3.5–5 μm. Controlled experiments, examining whether the foot traffic contribution was due to resuspension from carpeting or to shedding from clothing and/or human bodies, saw a significant increase in Aspergillus levels from resuspension. Although an increase was also seen for clothing over Tyvek suits, it was not statistically significant. 相似文献
77.
Nazrin S. N. Umar S. A. Halimah M. K. Marian M. M. Najwa Z. W. Jufa M. S. Syahirah M. T. Zuhasanah Z. Azlan M. N. Geidam I. G. Boukhris Imed Kebaili Imen 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(7):2513-2526
Journal of Inorganic and Organometallic Polymers and Materials - Copper oxide doped TeO2–B2O3 glass system with empirical formula;... 相似文献
78.
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80.
Grzegorz D. Sulka Joanna Kapusta-Ko?odziej Agnieszka Brzózka Marian Jasku?a 《Electrochimica acta》2010,55(14):4359-493
The formation of self-organized porous titania is achieved by electrochemical anodization under a potentiostatic regime. Anodic titanium oxide (ATO) was fabricated by a three-step self-organized anodization of the Ti foil in an ethylene glycol electrolyte containing 0.38 wt% of NH4F and 1.79 wt% of H2O. Anodizing was carried out at the constant cell potential ranging from 30 to 70 V at the temperature of 20 °C. It was found that nanoporous TiO2 arrays can be obtain only after a short duration of the third step (10 min). The influence of anodizing potential on the structural parameters of porous anodic titania including pore diameter, interpore distance, wall thickness, porosity and pore density was extensively studied. The linear dependencies between interpore distance, pore diameter and wall thickness upon the anodizing potential were found. The regularity of pore arrangement was monitored qualitatively by fast Fourier transforms (FFTs) of top-view FE-SEM images. It was found that the best arrangement of nanopores is observed at 40 V. This finding was confirmed by the analysis of pore circularity. The highest circularity of pores was observed once again at 40 V. 相似文献