New Type Of Target Research Articles

G Protein-Coupled Receptor Signaling: New Insights Define Cellular Nanodomains.

G protein-coupled receptors are the largest and pharmacologically most important receptor family and are involved in the regulation of most cell functions. Most of them reside exclusively at the cell surface, from where they signal via heterotrimeric G proteins to control the production of second messengers such as cAMP and IP3 as well as the activity of several ion channels. However, they may also internalize upon agonist stimulation or constitutively reside in various intracellular locations. Recent evidence indicates that their function differs depending on their precise cellular localization. This is because the signals they produce, notably cAMP and Ca2+, are mostly bound to cell proteins that significantly reduce their mobility, allowing the generation of steep concentration gradients. As a result, signals generated by the receptors remain confined to nanometer-sized domains. We propose that such nanometer-sized domains represent the basic signaling units in a cell and a new type of target for drug development.

Probing yields and angular distributions of Be(d,n) neutrons with novel target of compressed beryllium-powder

A comprehensive study was conducted in the Cyclotron laboratory at National Research Tomsk Polytechnic University on the use of a new type of target utilized in the production of fast-neutrons. The flux and spectra of the fast-neutrons emitted by a novel target of compressed beryllium powder were studied. The neutron angular distribution was measured using Fe and Al foils as detectors in different angular situations of the target relative to the incident deuteron beam. It was found that there are some discrepancies in the neutron flux at 0° degree for the detectors, up to about 20% for different target-beam angle. Likewise, the flux of neutrons in the energy range between 1 and 6 MeV make up about 83% of the total flux. Compering with previous works using solid target, we found an increase of nearly twice the yield of fast neutrons. And there is a probability that increase would rise steadily as the deuteron energies exceed 12 MeV as was the case in our work. The results of this study are new and promising and we can obtain a relatively greater neutron yield when using a compressed powder target. This is reflected positively on many applications that use fast-neutron beams, such as radiotherapy, radioactive isotopes, and even nuclear fusion experiments, among others.

Laser-produced plasma soft x-ray source based on an aerosol target

Laser produced plasma (LPP) soft x-ray and extreme ultraviolet sources utilize various types of targets. Some of them are based on gaseous targets. The most important disadvantage of such targets is the very limited number of elements that can be used in the gaseous form under normal conditions, including chemical compounds in the gaseous state. In this paper, the authors propose a new type of target, constituting an extension of the gaseous target, namely aerosol target, based on solutions of solid chemical compounds in liquids. Unlike previous attempts to produce aerosol targets from overheated liquids, in our system, the target is created by injection of a mist, preformed in a dedicated cell, into the vacuum chamber. Such targets have many advantages: the emission spectra can be adjusted by choosing proper chemical compounds, the aerosol target is elongated, hence, the laser focus can be positioned at a relatively long distance from the nozzle outlet, its average density can be higher compared to gaseous targets. In this work, such a target and its usefulness for the LPP soft x-ray source was demonstrated. The target was investigated by the soft x-ray backlighting method. Its density distribution at the position of the laser focus was determined. The emission spectra from the soft x-ray range, corresponding to multiple charged ions, originating from the solvent and the diluted salt were measured. Based on numerical simulations of the spectra, an ionic composition of the resulting plasmas was determined.

Generation of high quality ion beams through the stable radiation pressure acceleration of the near critical density target**Project supported by the National Natural Science Foundation of China (Grant Nos. 11365020, 11475026, 11565022, and 11547304), the Science and Technology Program of Gansu Province of China (Grant No. 1606RJZA090), the Fundamental Research Funds for the Higher Education Institutions of Gansu Province of

In order to generate high quality ion beams through the stable radiation pressure acceleration (RPA) of the near critical density (NCD) target, we propose a new type of target where an ultra-thin high density (HD) layer is attached to the front surface of an NCD target, which has a preferable self-supporting property in the RPA experiments than the ultra-thin foil target. It is found that in one-dimensional particle-in-cell (PIC) simulation, by the block of the HD layer in the new target, there emerges the hole-boring process rather than propagation in the NCD layer when the intense laser pulse impinges on this target. As a result, a typical RPA structure that the compressed electron layer overlaps the ion layer as a whole is formed and a high quality ion beam is obtained, e.g., a circularly polarized laser pulse with normalized amplitude impinges on this new target and a 1.2 GeV monoenergetic ion beam is generated through the RPA of the NCD layer. Similar results are also found in the two-dimensional PIC simulation.

Liquid crystal films as on-demand, variable thickness (50–5000 nm) targets for intense lasers

We have developed a new type of target for intense laser-matter experiments that offers significant advantages over those currently in use. The targets consist of a liquid crystal film freely suspended within a metal frame. They can be formed rapidly on-demand with thicknesses ranging from nanometers to micrometers, where the particular value is determined by the liquid crystal temperature and initial volume as well as by the frame geometry. The liquid crystal used for this work, 8CB (4′-octyl-4-cyanobiphenyl), has a vapor pressure below 10−6 Torr, so films made at atmospheric pressure maintain their initial thickness after pumping to high vacuum. Additionally, the volume per film is such that each target costs significantly less than one cent to produce. The mechanism of film formation and relevant physics of liquid crystals are described, as well as ion acceleration data from the first shots on liquid crystal film targets at the Ohio State University Scarlet laser facility.

Extensive Testing and Comparison of a New Type of Target for Use in Engineering Surveying

Abstract The paper deals with the testing of a special target for determining the exact dimensions of steel structures and their descriptions. In most cases, the accuracy required in mechanical engineering is on the order of millimetres, and the location of a point on a steel construction is marked by a centre punch. Due to the segmentation of steel constructions and the impossibility of the vertical placement of a target, it is very difficult to use ordinary prisms because of their size and the linear error from a wrong rotation and a nontrivial conversion of the centre of a prism into a centre punch on a steel construction. For a more accurate determination of spatial coordinates, a special reflective target with a reflective foil and a mechanical collimator, which ensures the correct angle to the target device according to the instructions of the person at the instrument, has been developed. Centration with a high degree of accuracy is achieved by a spike. Its functionality and usability goals have been tested and compared with standard methods of measurements and goals in engineering structures.

Design of a cone target for fast ignition

We propose a new type of target for the fast ignition of inertial confinement fusion. Pre-formed plasma inside a cone target can significantly reduce the energy coupling efficiency from the ultra-high intense short-pulse laser to the imploded core plasma. Also, in order to protect the tip of the cone and reduce generation of pre-formed plasma, we propose pointed shaped cone target. In our estimation, the shock traveling time can be delayed 20-30ps by lower-Z material with larger areal density compared to the conventional gold flat tip. Also, the jet flow can sweep the blow-off plasma from the tip of the cone, and the implosion performance is not drastically affected by the existence of pointed tip. In addition, the self- generated magnetic field is generated along the boundary of cone tip and surrounding CD or DT plasma. This magnetic field can confine fast electrons and focus to the implosion core plasma. Resultant heating efficiency is improved by 30% compared to that with conventional gold flat tip.

Latest Approach to Improve the Protection of Embedded Systems by Using PGP Technique

In today's world of ubiquitous computing, cyber attacks are becoming more virulent, costlier, and larger in scope than ever before. Unlike previous incarnations of hacking, current attacks on computer systems are professionally coordinated, multifaceted, and motivated by the promise of profits on a massive scale. With millions of new electronic devices connecting to the internet every day, hackers are increasingly focused on a new type of target: mobile and embedded systems. Such systems include point-of-sale terminals, wireless routers, phones, networked office machines such as printers, and even the utility infrastructure. Pass points scheme is one of the techniques used in Authentication using Graphical Images. In this method, users click on images rather than typing a long and complex alphanumeric password with the computer keyboard. Psychological studies have shown that people can remember pictures better than text. During the time of registration a user may choose several areas (click points) on an image. In order to log in the user has to click close to the chosen click points, e.g. within 0.25cm to 0.50cm from the click point, because users cannot click exactly on the same pixel on which they have clicked at the time of registration. This margin of error around the click point is called Tolerance. Existing Pass points scheme uses a fixed tolerance (say 20X20 pixels) over a number of clicks by the user. But by varying the tolerance (i.e., decrementing the tolerance level) as users click on more points, the information left to an attacker is reduced. We have also introduced multiple graphical passwords approach to counter shoulder surfing attack. Cutting-edge hackers are acutely aware that many of the security procedures and applications in use today have been designed for PC workstations, and are thus unable to thwart attacks on mobile and embedded systems. Smart phones, for example, remain notoriously insecure, yet they are gaining popularity as platforms for exchanging confidential data and conducting financial transactions. Billions of dollars are at risk as people do more and more of their everyday banking and shopping on mobile and wireless devices. Even heart pacemakers have joined the networked world and are now vulnerable to hacking. upsurge in cyber attacks against our utility infrastructure. If hackers continue to attack the so-called smart grid, which connects sensors and control systems with sophisticated computers and networks, they could bring our nation's commerce to a standstill, endanger lives, and put our national security at risk. Now a days, all business, government, and academic organizations are investing a lot of money for the security of information. In this dangerous new interconnected world, we need to take a serious look at what types of hacking strategies are being employed today, and implement security solutions that are designed specifically for mobile and embedded devices. This paper attempts to highlight some of the latest attacks against embedded systems, including mobile phones, medical devices, and the nation's electric infrastructure. A key area in securing the valuable information authentication. What is Authentication? Authentication refers to the process of verifying the Identity of a communication partner. It determines whether a user is allowed to access a particular system or resource. Today it is a critical area of security research. Authentication techniques can be classified into three categories. They are 1) Token based authentication 2) Biometric based authentication 3) Knowledge based authentication The classification is shown in Fig. 1. The best example for token based authentication is a bank cards like credit or debit. Some authentication systems also use knowledge based authentication technique to enhance the security of information. For example, ATM debit cards generally require a PIN number which is to be remembered by the user.

A Dim-Small Target Tracking Approach Based on Robust Hyperspectral Features

The dim-small target tracking is a central problem in several related applications. Subjected to the lack of objective information, traditional target tracking is difficult to meet the needs of dim-small target tracking. A dim-small target’s description based on robust spectral features is proposed to solve this problem. By creating a multi-dimensional feature space and extending the limited RGB information to the hyperspectral information, a new type of target’s description is presented to track the dim-small target with hyperspectral features.

New Interceptor Guidance Law Integrating Time-Varying and Estimation-Delay Models

The paper presents a synthesis of a new guidance law, derived using differential games concepts, for the interception of highly maneuvering targets. The synthesis is based on the integration of two recently demonstrated improvementfeatures:namely,theuseofa time-varying linearkinematicsgamemodelandthecompensationofthe inherent estimation delay of thetarget acceleration. The new guidance law is implemented in a genericyet realistic noise-corruptedthree-dimensionalnonlinearballisticmissiledefensescenariobyusingasuitablethree-dimensional estimator.Thetestagainstworst-casetargetmaneuversdemonstratesasignie cantimprovementcomparedto other known guidance laws indicating a potential breakthrough in interceptor guidance. I. Introduction H ISTORICALLY, the typical target of interceptor missiles has been a manned aircraft, against which the missile had substantial advantage in speed, maneuverability, and agility. Moreover, miss distances of a few meters, compatible with the lethal radius of the missile warhead, were considered admissible. Because of these facts, even a simple guidance law such as proportional navigation (PN) could guarantee the target destruction. The Gulf War introduced the tactical ballistic missile (TBM), able to carry nonconventional warheads, as a new type of target. Successful interception of a TBM, much less vulnerable than an aircraft, requires a very small miss distance or even a direct hit. Several ballistic missile defense systems are currently in development. Because of advances in technology, these systems (such as ARROW and PAC-3) succeeded to demonstrate, using conventionalguidance concepts, excellent homing accuracy against such nonmaneuvering targets. 1;2 Although known TBMs were not designed to maneuver because of their high reentry speed, they have a substantial maneuverability potential in the atmosphere. Moreover, this potential can be made applicable by a modest technical effort. The same is true for future high-speed antiship or cruise missiles.Paradoxically, the successful current development of ballistic missile defense systems can serve to motivate the future development of maneuverable antisurface missiles. Against such threats interceptor missiles will have only a marginal maneuverability advantage. Hence, the required small miss distances are not achievable by using conventional guidance laws even in a noise-free environment, as it was demonstrated by recent simulation studies. 3;4 Most missile guidance laws used at the present, including PN, were derived using a linear quadratic optimal control formulation assuming perfect information. 5 Such a formulation requires an assumption on the future evolution of the target maneuver. If this

Model of neutron-production rates from femtosecond-laser–cluster interactions

Solid deuterium clusters provide a new type of target for laser-matter interactions. We present a theory for the generation of laser driven Coulomb explosions that create a hot fusion-producing ion tail. We derive an initial distribution function for the exploded ions, for an arbitrary cluster-size distribution, and solve for the D-D neutron-production rate during the free expansion of these ions into a vacuum. We find good agreement between the theory and the experiment: the theory suggests an explanation for the observed saturation and drop in neutron yield beyond a definite cluster size, consistent with recent experiments by Ditmire [T. Ditmire et al., Nature 398, 489 (1999)] and Zweiback [J. Zweiback et al., Phys. Rev. Lett. 84, 2634 (2000); J. Zweiback et al., Phys. Rev. Lett. 85, 3640 (2000)].

Simple composition control of ferroelectric thin films grown by sputtering with an original oxides target design

We propose a new type of target which permits an easy control of composition for complex oxide films grown by sputtering. The targets consists of multilayers of PbO and TiO 2 for PbTiO 3 films and multilayers of PbO, TiO 2, ZrO 2 for PbZrTiO 3 films obtained by tape-casting and cold pressing. The composition of the film is controlled by the thicknesses of the different oxide layers and the erosion area of the target (magnetron sputtering). With this new target design we have sucessefully realized PbTiO 3 and PbZrTiO 3 thin films.

Copper Self-Sputtering by Planar Magnetron

Aiming at filling up deep holes with metal, self-sputtering of copper is performed in a wide pressure range of 10-2 Pa to 10-4 Pa. The high target current of 7 A to 10 A for a 4-inch planar magnetron target is essential to perform the self-sputtering process wherein a very high deposition rate of about 4 µm/min at 60 mm from the target surface is obtained. The lifetime of the planar target is from 1 h to 2 h. A new type of target which has protuberances on the erosion centers is produced by trial and error, and achieved a lifetime of 4 h. Deep holes on Si wafers, 1.17 µm in depth and 0.4 µm or 0.6 µm in diameter, are examined, and verry good bottom coverage of nearly 100% is obtained.

New Type of Target for the Measurement of Impulse Bits of Pulsed Plasma Thrusters

A new type of called a cylindrical target has been devised in which most of the rebounding particles leave the radially through slits attached to its side face. It is expected that with this the ambiguity inherent in methods, which is caused by insufficient momentum accommodation of rebounding particles, will disappear. In this paper it is shown that, by using this type of designed appropriately, impulse bits of pulsed plasma thrusters can be evaluated with sufficient accuracy.