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The purpose of the study was to prepare stable liposomally entrapped budesonide (BUD) for a dry powder inhaler (DPI) formulation. BUD liposomes composed of egg phosphatidyl choline and cholesterol were prepared by lipid film hydration technique and sonicated to have the desired size (<5 μm). A rapid method was used for separation of free drug by centrifugation at a lower centrifugal force (G value). Liposomal dispersion was subjected to lyophilization after blending BUD with cryoprotectant in varying bulk and mass ratios, and percent drug remaining entrapped after lyophilization was optimized. Comparative drug retention studies on storage of DPI formulations were carried out in accordance with International Conference on Harmonization guidelines. Critical relative humidity of the formulations was determined and reported as one of the manufacturing controls. Sucrose was found to be the most effective cryoprotectant when present on both sides of the lamellae of liposomes in a bulk strength of 500 mM and mass ratio of lipid:sugar; 1∶10. Blending of sorbolac before lyophilization showed better retention of encapsulated drug (95.59%). The respirable fraction of the product (20.69±1.50%) was comparable with that of the control (26.49±1.52%), suggesting that the liposomal BUD can be successfully delivered throughout the broncho-pulmonary tree. The findings demonstrate that liposome of BUD can be prepared with a high entrapment value, stabilized by lyophilization, and delivered as an aerosolized DPI. The stability studies of lyophilized product suggests a shelf-life of one year when stored under refrigeration (2°C–8°C). 相似文献
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A Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) is designed to distinguish humans from machines. Most of the existing tests require reading distorted text embedded in a background image. However, many existing CAPTCHAs are either too difficult for humans due to excessive distortions or are trivial for automated algorithms to solve. These CAPTCHAs also suffer from inherent language as well as alphabet dependencies and are not equally convenient for people of different demographics. Therefore, there is a need to devise other Turing tests which can mitigate these challenges. One such test is matching two faces to establish if they belong to the same individual or not. Utilizing face recognition as the Turing test, we propose FR-CAPTCHA based on finding matching pairs of human faces in an image. We observe that, compared to existing implementations, FR-CAPTCHA achieves a human accuracy of 94% and is robust against automated attacks. 相似文献
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Cortical and hippocampal gamma oscillations have been implicated in many behavioral tasks. The hippocampus is required for spatial navigation where animals run at varying speeds. Hence we tested the hypothesis that the gamma rhythm could encode the running speed of mice. We found that the amplitude of slow (20-45 Hz) and fast (45-120 Hz) gamma rhythms in the hippocampal local field potential (LFP) increased with running speed. The speed-dependence of gamma amplitude was restricted to a narrow range of theta phases where gamma amplitude was maximal, called the preferred theta phase of gamma. The preferred phase of slow gamma precessed to lower values with increasing running speed. While maximal fast and slow gamma occurred at coincident phases of theta at low speeds, they became progressively more theta-phase separated with increasing speed. These results demonstrate a novel influence of speed on the amplitude and timing of the hippocampal gamma rhythm which could contribute to learning of temporal sequences and navigation. 相似文献
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Gaurav Mudgal Brajesh Mudgal Mayank Anand Gururani Venkatesh Jelli 《Archives Of Phytopathology And Plant Protection》2013,46(3):282-286
Here, we first report hyperparasitism of Honey Suckeled Mistletoe, Dendrophthoe falcata var. falcata (Loranthaceae) by Pseudaulacaspis cockerelli (Diaspididae). The infected mistletoe was found parasitising branches of the Senna siamea host. Pear-shaped white spots were observed on abaxial and adaxial leaf surfaces, stem and few on the haustorial surfaces of the mistletoe. Close inspection revealed a yellowish-brown spot on individual white spots. These were identified on the basis of morphological features as Cockerell Scales hidden in the white-spot like self-secreted waxy armours. No incidence of such an infection was seen on any part of the mistletoe host, Senna siamea. 相似文献
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It is well known that an amino acid can be encoded by more than one codon, called synonymous codons. The preferential use of
one particular codon for coding an amino acid is referred to as codon usage bias (CUB). A quantitative analytical method, CUB and
a related tool, Codon Adaptative Index have been applied to comparatively study whole genomes of a few pathogenic
Trypanosomatid species. This quantitative attempt is of direct help in the comparison of qualitative features like mutational and
translational selection. Pathogens of the Leishmania and Trypanosoma genus cause debilitating disease and suffering in human
beings and animals. Of these, whole genome sequences are available for only five species. The complete coding sequences (CDS),
highly expressed, essential and low expressed genes have all been studied for their CUB signature. The codon usage bias of
essential genes and highly expressed genes show distribution similar to codon usage bias of all CDSs in Trypanosomatids.
Translational selection is the dominant force selecting the preferred codon, and selection due to mutation is negligible. In contrast
to an earlier study done on these pathogens, it is found in this work that CUB and CAI may be used to distinguish the
Trypanosomatid genomes at the sub-genus level. Further, CUB may effectively be used as a signature of the species differentiation
by using Principal Component Analysis (PCA).