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HTML, an ellipsis for Hypertext Markup Language, is meant exclusively for Web browsers. Apart from contents, it also includes information pertaining to their respective layout and format within its body. Any ASCII Text file can easily be converted into HTML file format by adding TAGs (called elements of HTML) to it and saving it with an '.html' file extension. HTML TAGs are language-specific reserve words enclosed in 'angle brackets' that in general come in pair referred to as 'start' and 'end tag'. Most importantly, HTML TAGs are case insensitive and allow for their structuring/re-ordering in a variety of ways. A Web browser is a software application that understands the HTML file format and displays its contents excluding TAGs according to the format specified in TAGs, if any. Web browser is responsible for traversing and retrieving Web resources on the Internet and presenting it before the end user. Hence, HTML documents seem an ideal cover for hiding secret information, as regardless of the manner HTML TAGs are manipulated within language constraints, the appearance of Web page before the human eye remains impervious. This paper introduces its reader to a novel digital steganographic method for hiding information inside the HTML document by changing the 'case' of English alphabet within HTML TAGs. The distinct characteristics of our proposed method in contrast to its antecedent include increased data-hiding capacity of the information carrier (HTML cover) and impermeable perceptibility of the altered carrier (HTML stego object), besides inducing randomness (concept supported by information theory) just before bit embedding ensues. [ABSTRACT FROM AUTHOR]

Abstract: The round-trip attenuating process of lasers used for guiding in artificial water mists is studied with the Monte-Carlo method. A new way for confirming the scattering directions of photons is established based on calculating Mie cumulative probability distribution function of the polydisperse mist and user defined function fitting by Matlab. Two Monte-Carlo methods for photons tracking are mentioned and their efficiencies are discussed and balanced in this paper. A conclusion is come to that the Wight method is evidently more efficiency than the Event method, and the former is adopted in this paper. The radiuses of frequently-used water mists are usually in the range of 101–102 μm which are found to be suited to attenuate the 10.6μm laser and can be used for laser stealth. But the effect is worse for 1.06μm laser. [Copyright &y& Elsevier]

Polyethylene glycol (PEG) is widely utilized in drug delivery and nanotechnology due to its reported 'stealth' properties and biocompatibility. It is generally thought that PEGylation allows particulate delivery systems and biomaterials to evade the immune system and thereby prolong circulation lifetimes. However, numerous studies over the past decade have demonstrated that PEGylation causes significant reductions in drug delivery, including enhanced serum protein binding, reduced uptake by target cells, and the elicitation of an immune response that facilitates clearance in vivo. This report reviews some of the extensive literature documenting the detrimental effects of PEGylation, and thereby questions the wisdom behind employing this strategy in drug development. [ABSTRACT FROM AUTHOR]

The screw propeller has been the mainstay of marine propulsion, but new de-velopments in biomimetic propulsion can provide advantages in terms of speed, maneuverability, efficiency, and stealth. The diversity of aquatic animals provides designs for drag-based paddling and lift-based oscillatory hydrofoils that can be incorporated into engineered propulsive systems for enhanced performance. While the screw propeller will remain the prominent propulsive device, the choice of alternative biomimetic propulsive systems will be dependent on particular ap-plications, where the specifications dictate improved performance criteria. [ABSTRACT FROM AUTHOR]

In today's world internet has emerged as an information hub which besides facilitating data sharing has logically connected people across the globe via chat, email, video conferencing etc. This ease of communication, however, is linked with serious security concerns of confidentiality, integrity, and non-repudiation that need to be addressed for secure communication. Steganography, one of the subdivisions of information hiding field, is now preferably been used in conjunction with cryptography to provide a doubly layered security shield to cater for the aforementioned confidentiality concern. This paper elaborates on a novel algorithm evolved for hiding sensitive information, twice in capacity as compared to its counterparts, inside ASCII text document/file. Also, conversion of stego objects to portable document format (.pdf) or when saved as MS Word (.doc), and converse, does not result in loss of hidden information or perceptibility. [ABSTRACT FROM AUTHOR]

Objective: To improve the therapeutic index of brucine, the novel stealth liposomes (SLS-n), composed of naturally unsaturated and hydrogenated soy phosphatidylcholines, with significant difference of phase transition temperature, were developed to encapsulate brucine. Methods: Brucine-loaded stealth liposomes with different lipid compositions were prepared and characterized for their entrapment efficiency (EE), particle size, zeta potential and in vitro drug release profile. Tissue distribution after intravenous administration of different brucine formulations was further compared in tumor-bearing mice. Results: Compared with the conventional stealth liposomes composed of SPC (SLS-s) or HSPC (SLS-h), EE and zeta potential of SLS-n were increased slightly, and the size was decreased slightly. The results of drug release showed that SLS-n were more stable than SLS-s. After intravenous administration, tumor AUC in SLS-s, SLS-n and SLS-h treated animals were 1.33, 1.72 and 2.59-fold higher than in mice treated with the same dose of free brucine, respectively. Compared with brucine solution, administration of SLS-s and SLS-n could significantly decrease brucine concentration in brain, but administration of SLS-h resulting in significantly increased (2.75-fold) concentration in 10 min. Conclusion: Since brucine has severe central nervous system toxicity, our study indicated that SLS-n could considerably improve the therapeutic index of brucine. [ABSTRACT FROM AUTHOR]

Purpose: This work describes a method for functionalisation of nanoparticle surfaces with hydrophilic 'nano-shields' and the application of advanced surface characterisation to determine PEG amount and accumulation at the outmost 10 nm surface that is the predominant factor in determining protein and cellular interactions. Methods: Poly(lactic-co-glycolic acid) (PLGA) nanoparticles were prepared with a hydrophilic PEGylated 'nano-shield' inserted at different levels by hydrophobic anchoring using either a phospholipid-PEG conjugate or the copolymer PLGA-block-PEG by an emulsification/diffusion method. Surface and bulk analysis was performed including X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance spectroscopy (NMR) and zeta potential. Cellular uptake was investigated in RAW 264.7 macrophages by flow cytometry. Results: Sub-micron nanoparticles were formed and the combination of (NMR) and XPS revealed increasing PEG levels at the particle surface at higher PLGA-b-PEG copolymer levels. Reduced cellular interaction with RAW 264.7 cells was demonstrated that correlated with greater surface presentation of PEG. Conclusion: This work demonstrates a versatile procedure for decorating nanoparticle surfaces with hydrophilic 'nano-shields'. XPS in combination with NMR enabled precise determination of PEG at the outmost surface to predict and optimize the biological performance of nanoparticle-based drug delivery. [ABSTRACT FROM AUTHOR]

Abstract: Engineering polymer surfaces reduces nanoparticles (NPs) aggregation and phagocytosis due to effective shielding, hindering recognition by the reticuloendothelial system (RES). The shielding of NPs is complex and affected by the type of groups used in terms of charge and hydrophilicity. This will, in turn, affect NPs biodistribution which will determine the length of activity of the drug. Polysaccharides are nowadays recognized for decreasing the uptake of particulate carriers by the mononuclear phagocytic system (MPS). Chitosan is considered as an attractive candidate due to its biocompatibility, biodegradability, non-toxicity and low cost. In this study clozapine (CZP)-loaded NPs were coated with chitosan, pluronic F-68, polyethylene glycol (PEG) 4000 and polysorbate 80. The factors affecting drug encapsulation efficiency, particle size, surface charge, surface hydrophilicity, pharmacokinetics and biodistribution were studied. The results proved that although a similarity in surface hydrophilicity, chitosan-stealth NPs showed different pharmacokinetic profile and biodistribution behavior compared to polysorbate-stealth NPs. [Copyright &y& Elsevier]

Abstract: A structure is discussed for absorbing incident radiation, either electromagnetic (EM) or sound. Such a surface structure is needed, for example, in a highly sensitive high-frequency gravitational wave or HFGW detector such as the Li-Baker. The multi-layer absorber, which is discussed, is constructed with metamaterial [MM] layer or layers on top. This MM is configured for a specific EM or sound radiation frequency band, which absorbs incident EM or sound radiation without reflection. Below these top MM layers is a substrate of conventional EM-radiation absorbing or acoustical absorbing reflective material, such as an array of pyramidal foam absorbers. Incident radiation is partially absorbed by the MM layer or layers, and then it is more absorbed by the lower absorbing and reflecting substrate. The remaining reflected radiation is even further absorbed by the MM layers on its “way out_ so that essentially all of the incident radiation is absorbed _ a nearly perfect black-body absorber. In a HFGW detector a substrate, such as foam absorbers, may outgas into a high vacuum and reduce the capability of the vacuum–producing equipment, however, the layers above this lowest substrate will seal the absorbing and reflecting substrate from any external vacuum. The layers also serve to seal the absorbing material against air or water flow past the surfaces of aircraft, watercraft or submarines. Other applications for such a multiple-level radiation absorber include stealth aircraft, missiles and submarines. [Copyright &y& Elsevier]

Abstract: The generation of control moments without moving control surfaces is of great practical importance. Following a successful flight demonstration of creating roll motion without ailerons using differential, lift oriented, flow control the current study is a first step towards generating yawing motion via differential flow controlled drag. A wind tunnel study was conducted on a 21% thick Glauert type airfoil. The upper surface flow is partially separated from the two-thirds chord location and downstream on this airfoil at all incidence angles. An array of mass-less Piezo-fluidic actuators, located at x/c =0.65, are capable of fully reattaching the flow in a gradual, controlled manner. The actuators are individually operated such that the boundary layer could be controlled in a 3D fashion. Several concepts for creating yaw motion without moving control surface are examined. The ultimate goal is to generate the same lift on both wings, while decreasing the drag on one wing and increasing the drag on the other, therefore creating a yawing moment. Decreased drag is created by effective part-span separation delay while increased drag can be created by enhanced generation of vortex shedding or by highly localized 3D actuation. Detailed measurements of 3D surface pressure distributions and wake data with three velocity and streamwise vorticity components are presented and discussed along with surface flow visualization images. The data provide evidence that yawing moments can be generated with AFC. [Copyright &y& Elsevier]

Infrared signature management (IRSM) has been a primary aeronautical concern for over 50 years. Most strategies and technologies are limited by the second law of thermodynamics. In this article, IRSM is considered in light of theoretical developments over the last 15 years that have put the absolute status of the second law into doubt and that might open the door to a new class of broadband IR stealth and cloaking techniques. Following a brief overview of IRSM and its current thermodynamic limitations, theoretical and experimental challenges to the second law are reviewed. One proposal is treated in detail: a high power density, solid-state power source to convert thermal energy into electrical or chemical energy. Next, second-law based infrared signature management (SL-IRSM) strategies are considered for two representative military scenarios: an underground installation and a SL-based jet engine. It is found that SL-IRSM could be technologically disruptive across the full spectrum of IRSM modalities, including camouflage, surveillance, night vision, target acquisition, tracking, and homing. [ABSTRACT FROM AUTHOR]

Purpose: Nanomedicines represent an alternative for the treatment of aggressive glioblastoma tumors. Behaviour of PLGA-nanoparticles (NPs) was here investigated as a function of their protein adsorption characteristics at the different biological interfaces they are expected to face in order to reach brain cancer cells. Methods: NPs were studied for size, zeta potential, blood half-life, in vitro endocytic behavior and in vivo accumulation within healthy rat brain and brain tumors. Results: While slightly modifying size (80 to 90 nm) and zeta potential (−44 to −32 mV) protein coating of PLGA-NPs by bovine serum albumin (BSA) or transferrin (Tf) greatly prolonged their blood half-life when intravenously injected in rats and mice. In contrast with THP-1 monocytes, differentiated THP-1 macrophages, F98 glioma cells and astrocytes internalized BSA- and Tf-NPs in vitro. Increase of Tf-NP uptake by F98 cells through caveolae- and clathrin-mediated pathways supports specific interaction between Tf and overexpressed Tf-receptor. Finally, in vivo targeting of healthy brain was found higher with Tf-NPs than with BSA-NPs while both NPs entered massively within brain-developed tumors. Conclusion: Taken together, those data evidence that Tf-NPs represent an interesting nanomedicine to deliver anticancer drugs to glioma cells through systemic or locoregional strategies at early and late tumor stages. [ABSTRACT FROM AUTHOR]

An intriguing question in weapons acquisition is why some weapons programs--initially designated Major Defense Acquisition Programs (MDAP)--collapse after a long development process, resulting in wasted money and expertise. A salient illustration is the RAH-66 Comanche stealth helicopter. For 20 years, the Army designated the RAH-66 an MDAP. Yet, in 2004 the Army decided that the RAH-66 was no longer affordable. What changes led the Service to reverse its position? This study shows that despite the explicit Army posture favoring the program, the Comanche had in fact suffered from an implicit and progressive decrease in support within the Service. [ABSTRACT FROM AUTHOR]

Abstract: The Mononuclear Phagocyte System (MPS) is a major constraint to nanocarrier-based drug-delivery systems (DDS) by exerting a negative impact on blood circulation times and biodistribution. Current approaches rely on the protein- and cell-repelling properties of inert hydrophilic polymers, to enable escape from the MPS. Poly(ethylene glycol) (PEG) has been particularly useful in this regard, and it also exerts positive effects in other blood compatibility parameters, being correlated with decreased hemolysis, thrombogenicity, complement activation and protein adsorption, due to its uncharged and hydrophilic nature. However, PEGylated nanocarriers are commonly found in the liver and spleen, the major MPS organs. In fact, a hydrophilic and cell-repelling delivery system is not always beneficial, as it might decrease the interaction with the target cell and hinder drug release. Here, a full scope of the immunological and biochemical barriers is presented along with some selected examples of alternatives to PEGylation. We present a novel conceptual approach that includes virulence factors for the engineering of bioactive, immune system-evasive stealth nanocarriers. From the Clinical Editor: The efficacy of nanocarrier-based drug-delivery systems is often dampened by the Mononuclear Phagocyte System (MPS). Current approaches to circumvent MPS rely on protein- and cell-repelling properties of inert hydrophilic polymers, including PEG. This paper discusses the full scope of the immunological and biochemical barriers along with selected examples of alternatives to PEGylation. [Copyright &y& Elsevier]

It is the purpose of this paper to investigate the aerodynamic properties of a supersonic intake converted to be used in stealth aircraft. The information sought regard both the airflow inside the intake duct and also the mechanical loading of the added elements. A computational fluid dynamics series of tests have been carried out and the results synthesized. It was found that although the intake could still be used for supersonic flight; the airflow will be severely distorted therefore imposing the use of circulation control. Also we could derive that the stresses on the fan rotor will be quite higher and asymmetrical in nature which will lead to shorter component life. The work could prove useful in understanding the limitations of stealthy supersonic aircraft and provide leads to further improvement in this field. [ABSTRACT FROM AUTHOR]

Abstract: Evaluation of the biocompatibility of pH-triggered targeting micelles was performed with the goal of studying the effect of a poly(ethylene oxide) (PEO) coating on micelle stealth properties. Upon protonation under acidic conditions, pH-sensitive poly(2-vinylpyridine) (P2VP) blocks were stretched, exhibiting positive charges at the periphery of the micelles as well as being a model targeting unit. The polymer micelles were based on two different macromolecular architectures, an ABC miktoarm star terpolymer and an ABC linear triblock copolymer, which combined three different polymer blocks, i.e. hydrophobic poly(ε-caprolactone), PEO and P2VP. Neutral polymer micelles were formed at physiological pH. These systems were tested for their ability to avoid macrophage uptake, their complement activation and their pharmacological behavior after systemic injection in mice, as a function of their conformation (neutral or protonated). After protonation, complement activation and macrophage uptake were up to twofold higher than for neutral systems. By contrast, when P2VP blocks and the targeting unit were buried by the PEO shell at physiological pH, micelle stealth properties were improved, allowing their future systemic injection with an expected long circulation in blood. Smart systems responsive to pH were thus developed which therefore hold great promise for targeted drug delivery to an acidic tumoral environment. [Copyright &y& Elsevier]

Copyright of Canadian Foreign Policy Journal (CFPJ) is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Intraoperative ultrasound (iUS) provides low-cost real-time imaging that is simple and rapid to use. Recent advances in probe technology, image fusion, 3D techniques and contrast have led to significant improvements in image quality. This article provides an overview of the current uses of iUS, including technical advice for practical use, and future directions. [ABSTRACT FROM AUTHOR]

Research provides strong support for the theory that drug market participants are often involved in violent retaliation because they lack access to formal mediation. Yet retaliation is not always violent. The existing drug market literature offers few counts, estimates, or stories of non-violent retaliation, and no single theory specifies the variable conditions that determine which form of retaliation occurs. This paper contributes to criminology by drawing on the necessary conditions perspective and qualitative data obtained from drug dealers to provide the conceptual and theoretical foundation for future criminological work, including the development of theories that explain variability in retaliatory forms, research that demonstrates whether any given theory is supported by data, and criminal justice policies that draw on theoretical and empirical knowledge to reduce all forms of drug market retaliation—violent and non-violent. [ABSTRACT FROM AUTHOR]

Radar cross-section (RCS) is an important study parameter for defence applications specially dealing with airborne weapon system. The RCS parameter guides the detection range for a target and is therefore studied to understand the effectiveness of a weapon system. It is not only important to understand the RCS characteristics of a target but also to look into the diagnostic mode of study where factors contributing to a particular RCS values are studied. This further opens up subject like RCS suppression and stealth. The paper discusses the RCS principle, control, and need of measurements. Classification of RCS in terms of popular usage is explained with detailed theory of RF imaging and inverse synthetic aperture radar (ISAR). The various types of RCS measurement ranges are explained with brief discussion on outdoor RCS measurement range. The RCS calibration plays a critical role in referencing the measurement to absolute values and has been described. The RCS facility at Research Centre Imarat, Hyderabad, is explained with some details of different activities that are carried out including RAM evaluation, scale model testing, and diagnostic imaging. [ABSTRACT FROM AUTHOR]

This article considers the implications of cultural values, political-cultural arrangements and the changing mediascape for the distinct cultural resources on crime and punishment that we consume as citizens. It first explores what we mean when we talk about punitiveness, making the important, yet often overlooked, distinctions between public attitudes, political rhetoric, public policy and penal practice. Next, the ways in which the media constrain how we perceive problems and the means of solving them are considered, especially the ways these constraints are influenced by different political-cultural styles. 'Stealth' penal reforms, in which punitive rhetoric is employed by politicians to divert attention away from more progressive policies pursued quietly on the sly, are criticized because they tend to legitimize and regenerate only punitive ideational resources for public consumption. Finally, implications for future research are offered along with some practical suggestions for enriching public discourse in order to nourish and sustain a broader range of understandings and responses to crime. [ABSTRACT FROM AUTHOR]

Nanoparticles (prepared from a mixture of polyester and a polycationic polymer) loaded with insulin were prepared by a double emulsion method followed by evaporation solvent. Low molecular weight heparin (LMWH) was bound by electrostatic interactions onto the surface of the particles to confer Stealth properties. These nanoparticles were characterized in vitro (mean diameter, zeta potential, encapsulation efficiency, and release kinetics) and compared with conventional (without LMWH) and unloaded nanoparticles. The pharmacokinetics of insulin were studied after intravenous injection into diabetic rats in the form of Stealth or conventional nanoparticles or as a solution. Stealth nanoparticles allowed an increase in the elimination half-life of insulin, showing that the hydrophilic layer of LMWH was able to limit recognition by the mononuclear phagocytosis system in vivo. However, complement activation studies (CH50) did not reveal significant difference between Stealth and conventional nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Viral stealth marketing is a contemporary marketing technique, which has evolved in reaction to the increasingly competitive marketing environment. This paper notes that despite its huge potential, very little research is being targeted towards understanding the utility of viral stealth marketing, particularly in the context of Generation Y, whose behavioural characteristics are particularly suited to this form of marketing. This paper explores the nature of viral stealth marketing and its ethical implications; then formulates an agenda for future research that has a potential to add significant value to organisations. [Copyright &y& Elsevier]

Abstract: RAS (radar absorbing structures) is a key component for weapon systems such as aircrafts, warships, and missiles to achieve both the stealth performance by absorbing EM (Electromagnetic) waves incident on and load bearing capability. In this work, the RAS was fabricated as sandwich constructions composed of nanocomposite, carbon fabric/epoxy composite, and PVC foam. The nanocomposite composed of E-glass fabric, epoxy resin, and CNT (carbon nanotube) was adhesively bonded to the outside of the sandwich construction in order to absorb EM waves. The carbon fabric/epoxy composite had the dual roles as the reflection layer of incident EM waves and load bearing face material of sandwich constructions. Using the fabricated sandwich constructions, the EM absorbing characteristics were measured by the free space measurement system and the bonding characteristics between nanocomposites and carbon fabric/epoxy composites also were investigated. [Copyright &y& Elsevier]

Passive Millimeter-Wave (MMW) detection has become a threat to ground targets. To enhance the survivability of the ground target in the future battlefield, passive MMW stealth technology is analyzed in this paper. Based on the passive MMW detection principle, computation and analysis are made for the MMW apparent temperature of tank in different actual combat conditions. The necessity of the passive MMW stealth is analyzed and the passive MMW stealth methods are also studied. [ABSTRACT FROM AUTHOR]

Abstract: Infrared (IR) emissions from aircraft are used to detect, track, and lock-on to the target. MAN Portable Air Defence Systems (MANPADS) have emerged as a major cause of aircraft and helicopter loss. Therefore, IR signature studies are important to counter this threat for survivability enhancement, and are an important aspect of stealth technology. This paper reviews contemporary developments in this discipline, with particular emphasis on IR signature prediction from aerospace vehicles. The role of atmosphere in IR signature analysis, and relation between IR signature level and target susceptibility are illustrated. Also, IR signature suppression systems and countermeasure techniques are discussed, to highlight their effectiveness and implications in terms of penalties. [Copyright &y& Elsevier]

In this article, we present a new kind of a controllable metamaterial electromagnetic structure that it may be applied into stealth design and stealth technology in the future, in which the transmission coefficient of electromagnetic wave and single radar cross section (RCS) of structure are both electrically controlled, simulated, and characterized between 7 and 12 GHz. This structure is constructed with split ring resonators (SRRs) and metallic wire arrays including pin diodes, pin diodes are periodically inserted at these discontinuous each 10 mm to control the electrical continuity of the wires, and they can be either in an on state or in an off state depending on the voltage. the simulation and test prove that this structure could absorb electromagnetic incident wave, and have reduced RCS markedly with the largest scope of -6 dBm around frequency 9.0 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1616–1619, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22521 [ABSTRACT FROM AUTHOR]

We describe a new type of threat to the Internet infrastructure, in the shape of a highly efficient but very well camouflaged click-fraud attack on the advertising infrastructure. The attack, which we refer to as a “badvertisement,” is described and experimentally verified on several prominent advertisement schemes. This stealthy attack can be thought of as a threatening mutation of spam and phishing attacks, with which it has many commonalities, except for the fact that it is not the targeted individual who is the victim in the attack, but the unwitting advertiser. [ABSTRACT FROM AUTHOR]

Stealth solid lipid nanoparticles (SSLN) were prepared and evaluated for the effect of evading phagocytic uptake by mouse peritoneal macrophages in situ. Fluorescent SSLNs were prepared by emulsion/evaporation with rhodamine B as the fluorescent marker and polyoxyethylene stearate as stealth agent in a stearic acid matrix. Macrophages were induced chemically through intraperitoneally injecting 1% sodium thioglycolate. After 4 days of cultivation, SSLNs suspension was injected intraperitoneally and phagocytosis taken out in situ. At definite time intervals, peritoneal fluid was drawn out and analyzed by flow cytometer. Maximium uptake by macrophages was observed at 2 hr after injection of nanoparticles. At all time intervals, phagocytic uptake of Solid lipid nanoparticles (SLNs) was better than SSLNs. Longer and dense polyethylene glycol chains led to reduced uptake by macrophages. Both SSLNs and SLN had uptake by macrophages to some extent, and the in situ model was suitable for evaluating interactions between cells and nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to reveal the influence of methoxypolyethyleneglycol (MePEG) molecular weight and particle size of stealth nanoparticles on their in vivo tumor targeting properties. Three sizes (80, 170 and 240nm) of poly methoxypolyethyleneglycol cyanoacrylate-co-n-hexadecyl cyanoacrylate (PEG-PHDCA) nanoparticles loading recombinant human tumor necrosis factor-α (rHuTNF-α) were prepared at different MePEG molecular weights (MW=2000, 5000 and 10,000) using double emulsion method. The opsonization in mouse serum was evaluated by Coomassie brilliant blue staining of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Phagocytosis was evaluated by incubating 125I-rHuTNF-α-loaded nanoparticles with mouse macrophages (RAW264.7). The pharmacokinetics, biodistribution and tumor targeting studies were performed in S-180 tumor-bearing mice. Higher MePEG molecular weight provided thicker fixed aqueous layer thickness (FALT) and smaller particle size offered higher surface MePEG density. The serum protein adsorption and phagocytic uptake were markedly decreased for the nanoparticles with higher MePEG molecular weight or smaller size. The particles (80nm) made of PEG5000-PHDCA, possessing a thicker FALT (5.16nm) and a shortest distance (0.87nm) between two neighboring MePEG chains, showed the strongest capacity of decreasing protein adsorption and phagocytic uptake. These particles extended the half-life of rHuTNF-α in S-180 tumor-bearing mice by 24-fold (from 28.2min to 11.33h), elevated the rHuTNF-α peak concentration in S-180 tumors by 2.85-fold and increased the area under the intratumoral rHuTNF-α concentration curve by 7.44-fold. The results of the present study showed PEG-PHDCA nanoparticles with higher MePEG molecular weight and smaller particle size could achieve higher in vivo tumor targeting efficiency. [Copyright &y& Elsevier]

Abstract: This paper assesses aircraft susceptibility from the first principles, with respect to the threat posed by passively guided infrared homing missiles; with an objective of gaining insight into the comprehensiveness of the relationship between aircraft susceptibility and aircraft infrared signature level. The conventional criterion of aircraft susceptibility assessment based on its lock-on envelop is found to be inadequate, and a new criterion termed here as the Lethal Envelop is presented. The proposed susceptibility assessment criterion is more relevant for coming generation of infrared-guided missiles, because of advancements in the infrared detection technology. A threshold infrared signature level is also proposed as benchmark to be satisfied by all infrared signature suppression systems; if aircraft susceptibility to infrared guided missiles is to be reduced. This analysis is vital for gauging the effectiveness of infrared signature suppression systems. A typical air-to-air combat situation is simulated, and the results that lead to aircraft susceptibility assessment are obtained from this model, which illustrates the comprehensiveness of the redefined aircraft susceptibility assessment approach. [Copyright &y& Elsevier]

To study thein vitrorelease of recombinant human tumor necrosis factor-alpha (rHuTNF-α) encapsulated in poly (methoxypolyethyleneglycol cyanoacrylate-co-n-hexadecyl cyanoacrylate) (PEG-PHDCA) nanoparticles, and investigate the influence of methoxypolyethyleneglycol (MePEG) molecular weight and particle size.Three sizes (approximately 80, 170, and 240 nm) of PEGPHDCA nanoparticles loading rHuTNF-α were prepared at different MePEG molecular weights (Mr=2000, 5000, and 10 000) using the double emulsion method. Thein vitrorHuTNF-α release was studied in PBS and rat plasma.A higher burst-release and cumulative-release rate were observed for nanoparticles with higher MePEG molecular weight or smaller particle size. A decreased cumulative release of rHuTNF-α following the initial burst effect was found in PBS, while the particle sizes remained constant and MePEG liberated. In contrast, in rat plasma, slowly increased cumulative-release profiles were obtained after the burst effect. During a 5-h incubation in rat plasma, more than 50% of the PEGPHDCA nanoparticles degraded. Conclusion: The MePEG molecular weight and particle size had an obvious influence on rHuTNF-α release. rHuTNF-α released from PEG-PHDCA nanoparticles in a diffusion-based pattern in PBS, but in a diffusion and erosion-controlled manner in rat plasma. [ABSTRACT FROM AUTHOR]

The introduction of microwave radars during the second World War altered the air defense scenario significantly, and this led to the development of the “stealth” techniques. By reducing the detectability of aircrafts or warships, of which the radar cross section (RCS) is a measure, they could evade radar detection, which affected not only the mission success rate but also survival of them in the hostile territory. In the very early stage of the research on stealth techniques, many researches were mainly concentrated on the reduction of RCS and development of radar absorbing materials (RAM), but nowadays studies on investigating the radar absorbing structures (RAS) using fiber reinforced polymeric composite materials are becoming popular research field.In this study, electromagnetic characteristics of unidirectional E-glass fiber reinforced epoxy composites were tested with free space methods, which can overcome drawbacks of conventional cavity and waveguide methods. Complex relative permittivities of low-loss composite were measured with respect to the angle between the fiber orientation and the electric field vector of EM wave in X-band frequency range. From the experimental data, empirical relation between the dielectric properties of composites and test variable was suggested and verified. [Copyright &y& Elsevier]

Weapons of both defense and offense have grown steadily in their effectiveness--especially since the industrial revolution. The mass destruction of humanity, by parts or in whole, became reality with the advent of toxic agents founded on chemistry and biology or nuclear weapons derived from physics. The military's new non-combat roles, combined with a quest for non-lethal weapons, may change the picture in regard to conventional defense establishments but are unlikely to deter bellicose tyrants or the new terrorists from using the unlimited potential of today's and tomorrow's arsenals. The author addresses the issues that are raised by this developing situation with the intent of seeking those ethics that will enable us to survive in a future and uncertain world. [ABSTRACT FROM AUTHOR]

Throughout history, nations have endeavored to develop new and more advanced technologies with the goal of achieving military advantage. New technologies resulted in new weapons and brought dramatic change in military tactics. The increase in the destructive power of soldiers in the Civil War and the resulting horror and futility of the frontal assault ushered in a change to trench warfare. The military aircraft, tanks, and the newly developed radio and radar made a new kind of dynamic warfare possible during World War II.World War II ended with a remarkable technological achievement: the development of the atomic bomb. In response, the Soviet Union detonated its first atomic bomb in 1949, followed by their successful test of a hydrogen bomb. By the early-1950s, missile programs were underway in both countries. In the absence of knowledge, the American threat assessments, and therefore the American response, were based on worst-case scenarios. The response of the Soviet Union was also based on their worst-case scenarios. Recognizing the dangers of this arms race in the dark, President Eisenhower authorized the secret development of a new generation of sensors and reconnaissance satellites, the successors of which are still vital to our security. Then, in response to the Soviet quantitative advantage in military forces, the US conceived a new “system of systems” of intelligence sensors, smart weapons and stealth aircraft. These new systems were developed during the late-1970s, produced in the early-1980s, and entered into the force in the late-1980s—just in time for Desert Storm.Today the threat of terrorism and the threat of proliferation are the greatest threats to our security. It seems likely that the American military will remain the dominant military force in the world for the foreseeable future, but this can have unintended consequences. It can lead to a nightmare scenario where a terror group may attack us with weapons of mass destruction. Advanced information technology is critical to countering this threat. There are technological opportunities in all the components of homeland security: intelligence, prevention, protection of infrastructure, detection of attacks, and consequence management. But these improvements will not evolve automatically. It is boldness and single-minded dedication that we must summon to respond to the threat of weapons of mass destruction in our cities. We must mobilize the scientific community as was done in World War II and in the Cold War. [Copyright &y& Elsevier]

The adsorption/release behavior of oligodeoxynucleotides (ODNs) on new PEGylated core-shell polymethylmethacrylate nanospheres is described. The outer shell consists of alkyl chains containing quaternary ammonium groups and of poly(ethylene glycol) chains, both covalently bound to the inner core. Ion pair formation between negatively charged ODN phosphate groups and positively charged groups on the nanosphere surface is the main interaction mechanism. No cellular toxicity in HL60 cells is observed at nanosphere concentrations required for biologically active ODN delivery. These results indicate that these novel cationic polymeric nanoparticles are safe and represent promising vectors for oligonucleotide delivery. [ABSTRACT FROM AUTHOR]

Stealth (pegylated) liposomal doxorubicin (Doxil) has been extensively studied at the pre-clinical and clinical level in recent years. However, one issue not yet addressed is the effect of dose on tumor localization and therapeutic efficacy of Doxil. Although it has been reported that the pharmacokinetics of drug-free Stealth liposomes is independent of dose within a certain range, clinical pharmacokinetic analysis of Doxil suggests a dose-dependent clearance saturation phenomenon when a broad dose range is examined. In addition, liposome-encapsulated doxorubicin can exert toxic effects on the liver macrophage population in the form of impairment of the phagocytic function and reduced ability of colloid particle clearance. In studies with tumor-bearing mice in which the dose of Doxil was escalated from 2.5 to 20 mg/kg, we demonstrate that dose escalation results in a saturation of Doxil clearance and a disproportional increase of the amount of liposomal drug accumulating in tumor. Experiments with radiolabeled highly negatively-charged liposomes injected into mice previously treated with Doxil are consistent with a partial blockade of the reticulo-endothelial system with relative reduction of liver uptake and greater prolongation of liposome circulation time. The clearance saturation effect is seen after Doxil in a dose-dependent fashion, and not after a similar free doxorubicin dose or similar phospholipid dose in drug-free liposomes. A trend to superior therapeutic efficacy for treatments based on larger doses as compared to smaller split doses, while maintaining an equivalent dose intensity, was also observed. These observations may be relevant to the choice of dose-schedule of Doxil to ensure optimal anti-tumor activity. Therefore, dose-dependent liposomal doxorubicin blockade of the reticulo-endothelial system may prolong liposome circulation time and enhance significantly drug delivery to tumors. [ABSTRACT FROM AUTHOR]

Targeted drug delivery requires binding to (and subsequent uptake by) the carrier and target cell. In this paper, we calculate the work required to bring into contact liposomal carriers and cells as a function of the liposome and cell electrostatic characteristics. We find that cell–liposome adhesion is sensitive to the cell type and optimized at a cell to liposome charge ratio which depends on the degree of cell charge regulation. As a result, uptake (which is dependent on the occurrence of binding) is also optimized. Incorporation of a (poly)ethylene glycol (PEG) layer enhances liposome adhesion in cases where the cell–liposome interactions are repulsive, and suppresses adhesion in systems where the interactions are attractive. Our results, which are in agreement with experimental observations, show that electrostatic interactions may be designed to enable targeted drug delivery by liposomes to a specific cell population. [Copyright &y& Elsevier]

The materials essential to the modern military helicopter are reviewed. In addition to materials of high specific strength and stiffness, such as aluminium alloys and fibre-reinforced composites, more specialized materials are also considered. These include materials for armour protection and signature reduction. As helicopters are used closer to the battle zone and in more important military roles, these requirements of protection and low observability become more important. [ABSTRACT FROM AUTHOR]

Pegylated liposomal doxorubicin (Doxil, Caelyx) is a formulation of doxorubicin in poly(ethylene glycol)-coated (stealth) liposomes with a prolonged circulation time and unique toxicity profile. We review the preclinical and clinical pharmacology as well as recent clinical data obtained in specific cancer types. Doxil liposomes retain the drug payload during circulation and accumulate preferentially in tissues with increased microvascular permeability, as often is the case of tumors. Doxil toxicity profile is drastically different from that of doxorubicin, and is characterized by dominant and dose-limiting mucocutaneous toxicities, mild myelosuppression, minimal alopecia, and no apparent cardiac toxicity. Although the single maximum tolerated dose (MTD) of Doxil is actually lower than that of conventionally administered doxorubicin, the cumulative MTD dose of Doxil may be substantially greater than that of free doxorubicin. Doxil is probably one of the most active agents in AIDS-related Kaposi's sarcoma and has a definite role in management of recurrent ovarian cancer. The potential of Doxil in the treatment of other cancer types and the opportunities it offers in combination with other drugs and therapeutic modalities are under active investigation. [ABSTRACT FROM AUTHOR]