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Recent reports of the use of ultrasound for communication by nocturnal mammals have expanded our understanding of behaviour in these animals. The vocal repertoire of colugos has so far only been known to include audible sound. Here, we report the use of ultrasound calls by Sunda colugos (Galeopterus variegatus, order Dermoptera). We recorded one type of call emitted by seven individuals with mean individual frequencies between 37.4 ± 0.6 and 39.2 ± 0.7 kHz during its maximum energy and lasting 28.7 ± 1.6 to 46.9 ± 21.1 ms. Each call showed 3–36 sequential pulses with individual mean interpulse intervals between 423.0 ± 101.4 and 1230.0 ± 315.4 ms. High frequency calls may serve as cryptic anti-predator alarm calls. Our observations suggest that more species of nocturnal mammals may use ultrasound to communicate, and that further studies are needed to determine the occurrence, function and diversity of these calls.  相似文献   
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In Vitro Cellular & Developmental Biology - Plant - Hibiscus moscheutos L., also known as hardy hibiscus, is valued for its medicinal and ornamental attributes. It is usually propagated via...  相似文献   
264.
A total of 55 taxa belonging to Trachelomonas (Euglenophyta) are reported from Bangladesh. Of these, 5 varieties (Tr. allorgei var. madaripurense, Tr. anguste-ovata var. ellipsoidea, Tr. armata var. rangpurense, Tr. hispida var. subcoronata, Tr. asymmetrica var. crenulata) and one forma (Tr. anguste-ovata fa. minor) are described as new to science.  相似文献   
265.
Eight species of Vaucheria from southern Iraq, V. dichotoma, V. sessilis, V. erythrospora, V. verticillata, V. hamata, V. woroniniana, V. synandra, and V. longicaulis were studied and described. All but V. sessilis and V. longicaulis are recorded for the first time from Iraq.  相似文献   
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This paper describes a refinement in the purification step that facilitated the downstream recovery of high purity BmR1 recombinant protein, which is a protein used as a test reagent in the commercialized rapid tests for detection of lymphac filariasis i.e. Brugia RapidTM and panLF rapidTM. Purification was performed by immobilized metal affinity chromatography (IMAC), followed by ion exchange chromatography (IEX). Results showed that a total of 10.27 mg of BmR1 was obtained when IMAC was performed using 20 mM of imidazole and 5 column volume of wash buffer containing 500 mM of NaCl. Purity of the target protein was enhanced when buffer at pH 5.8 was used during the IEX. Two proteins that recurrently appeared below the BmR1 recombinant protein were identified by mass-spectrometry analysis as the same protein, thus they were probably degradation products of BmR1. These strategies improve purity of the target protein to be used in applications such as production of aptamers and monoclonal antibodies.  相似文献   
268.
Distinct substructures within the nucleus are associated with a wide variety of important nuclear processes.Structures such as chromatin and nuclear pores have specific roles,while others such as Cajal bodies are more functionally varied.Understanding the roles of these membraneless intra-nuclear compartments requires extensive data sets covering nuclear and compartment-associated proteins.NSort/DB is a database providing access to intra-or sub-nuclear compartment associations for the mouse nuclear proteome.Based on resources ranging from large-scale curated data sets to detailed experiments,this data set provides a high-quality set of annotations of non-exclusive association of nuclear proteins with structures such as promyelocytic leukaemia bodies and chromatin.The database is searchable by protein identifier or compartment,and has a documented web service API.The search interface,web service and data download are all freely available online at http://www.nsort.org/db/.Availability of this data set will enable systematic analyses of the protein complements of nuclear compartments,improving our understanding of the diverse functional repertoire of these structures.  相似文献   
269.
Journal of Applied Phycology - Sodium bicarbonate (NaHCO3) is a low-cost inorganic carbon source, highly soluble in water and widely used in microalgae research. Using carbon dioxide (CO2) gas in...  相似文献   
270.
Thermolysin was stabilized by increasing the reaction temperature from 90°C to 110°C during peptide synthesis of N-(benzyloxycarbonyl)-L-phenylalanyl-L-phenylalanine methyl ester (Z-Phe-Phe-OMe). The stabilization energy was acquired from the drop in both pH and dielectric constant due to the temperature increase. The acquired stabilization energy was as high as ca. 42 kJ/mol (corresponding to 20°C). This acquired stabilization energy did not result from a single event such as a change in electrical charges. It was evaluated as the overall stabilization energy at and around the active site area of the enzyme using an electrostatic potential equation.  相似文献   
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