1,601 research outputs found
X-ray studies on crystalline complexes involving amino acids and peptides. Part XIV. Closed conformation and head-to-tail arrangement in a new crystal form of L-histidine L-aspartate monohydrate
A new form of L-histidine L-aspartate monohydrate crystallizes in space group P21 with a = 5·131(1), b = 6·881(1), c= 18·277(2) Å, β= 97·26(1)° and Z = 2. The structure has been solved by the direct methods and refined to an R value of 0.044 for 1377 observed reflections. Both the amino acid molecules in the complex assume the energetically least favourable allowed conformation with the side chains staggered between the α-amino and α-carboxylate groups. This results in characteristic distortions in some bond angles. The unlike molecules aggregate into alternating double layers with water molecules sandwiched between the two layers in the aspartate double layer. The molecules in each layer are arranged in a head-to-tail fashion. The aggregation pattern in the complex is fundamentally similar to that in other binary complexes involving commonly occurring L amino acids, although the molecules aggregate into single layers in them. The distribution of crystallographic (and local) symmetry elements in the old form of the complex is very different from that in the new form. So is the conformation of half the histidine molecules. Yet, the basic features of molecular aggregation, particularly the nature and the orientation of head-to-tail sequences, remain the same in both the forms. This supports the thesis that the characteristic aggregation patterns observed in crystal structures represent an intrinsic property of amino acid aggregation
Scene Projection by Non-Linear Transforms to a Geo-Referenced Map for Situational Awareness
There are many transportation and surveillance cameras currently in use in major cities that are close to the ground and show scenes from a perspective point of view. It can be difficult to follow an object of interest across multiple cameras if many of these cameras are in the same area due to the different orientations of these cameras. This is especially true when compared to wide area aerial surveillance (WAAS).
To correct this problem, this research provides a method to non-linearly transform current camera perspective views into real world coordinates that can be placed on a map. Using a perspective transformation, perspective views are transformed into approximate WAAS views and placed on a map. All images are then on the same plane, allowing a user to follow an object of interest across several camera views on a map. While these transformed images will not fit every feature of the map as WAAS images would, the most important aspects of a scene (i.e. roads, cars, people, sidewalks etc.) are accurate enough to give the user situational awareness.
Our algorithm is proven to be successful when tested on cameras from the downtown area of Dayton, Ohio
Development of electro-trawl system in marine environment
High voltage pulsed current produced on board a trawler is fed to electrodes distributed along the foot rope of a trawl net through two core TRS cable which builds up a homogeneous electrical field around the net mouth. By comparative fishing tests with the electrified and non-electrified 32 m long wing trawl net, the increase in total catch of shrimps and fishes was found to be 19.8 and 36%, respectively
Time-resolved observation of spin-charge deconfinement in fermionic Hubbard chains
Elementary particles such as the electron carry several quantum numbers, for
example, charge and spin. However, in an ensemble of strongly interacting
particles, the emerging degrees of freedom can fundamentally differ from those
of the individual constituents. Paradigmatic examples of this phenomenon are
one-dimensional systems described by independent quasiparticles carrying either
spin (spinon) or charge (holon). Here we report on the dynamical deconfinement
of spin and charge excitations in real space following the removal of a
particle in Fermi-Hubbard chains of ultracold atoms. Using space- and
time-resolved quantum gas microscopy, we track the evolution of the excitations
through their signatures in spin and charge correlations. By evaluating
multi-point correlators, we quantify the spatial separation of the excitations
in the context of fractionalization into single spinons and holons at finite
temperatures
Assessing burden and depth of hepatitis B infection within Asian Pacific islander families in San Francisco
ANTI-EPILEPTIC DRUG LOADED NIOSOMAL TRANSDERMAL PATCH FOR ENHANCED SKIN PERMEATION
Objective: To formulate and characterize midazolam loaded niosomal transdermal patches for overcoming the frequent dosing and lower bioavailability complications associated with conventional therapy.
Methods: The loaded niosomal transdermal patches were prepared by thin film hydration method. The preliminary evaluation and characterization studies was conducted to find the optimised formulation. The in vitro release and ex-vivo permeation studies were investigated. The histopathological studies and stability studies were also assessed.
Results: The midazolam loaded niosomal transdermal patches of vesicle size and zeta potential 116.1±84.46 d. nm and 8.56±1.2 mV respectively was formulated. The characterizations of both niosome and niosomal transdermal patches were found to be within the acceptable limits. The in vitro drug release showed an initial burst release followed by sustained release for both optimised niosomal formulation N5 and optimised niosomal transdermal patch formulation NT5with a maximum activity at 97.3±0.35% and 98.9±0.20% respectively. The ex vivo permeation studies of niosomal transdermal patch NT5 was performed which showed a higher permeability than control solution with a flux value of 0.151. The histopathological studies of the optimised formulation showed no detectable lesions upon skin surface and irritations. The stability studies showed that patches were stable over 90 d in different atmospheric conditions.
Conclusion: The midazolam loaded niosomal transdermal patch was found to be a promising nano drug delivery alternative which showed better entrapment, release with permeation profile for the daily management of epilepsy with decreased dosing frequency
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