Effect of reactive dyeing on the UV protection affected by knitted fabric made from different types of cotton fibre

In this study, 100% cotton knitted fabrics made from combed cotton and combed pima cotton were dyed with reactive dye, with different dye concentrations. Colour properties such as CIE L*a*b* values as well as dyeing uniformity of the dyed fabrics were measured. The relationships between colour properties and the ultraviolet protection afforded by cotton knitted fabrics were investigated. Experimental results revealed that dye concentration is the most important factor. In addition, only L* values have a direct mathematical relationship with the ultraviolet protection factor; a* and b* values and dyeing uniformity were not found to have a significant correlation with ultraviolet protection factor values. Meanwhile, knitted fabric made from combed cotton fibre has better ultraviolet protection performance than fabric made from combed pima cotton fibre.     

Open Signaling for ATM Networks: A Vexed Question of Performance

Based on a clear separation between switching hardware and control software, the concept of open signaling creates an open programmable networking environment in which network entities can be realized as high level software objects with well-defined interfaces. This underlying architecture facilitates the creation of multiple mechanisms of network control, supporting applications for connection management. The feasibility of a connection management framework however depends mainly on the performance of CORBA because of binding overheads associated with remote invocations. It has been proposed that an implementation with reasonable performance may require certain criteria to be integrated into the design, including caching of network states, aggregation of access to the switch server object, and parallel processing of a single call request. This paper considers the effectiveness of these design criteria and the associated performance issues of a connection management system for ATM networks.     

Adaptive Chosen-Ciphertext Attack on Secure Arithmetic Coding

The paper ldquosecure arithmetic codingrdquo (in IEEE Transactions on Signal Processing, vol. 55, no. 5, pp. 2263-2272, May 2007) presented a novel encryption scheme called the secure arithmetic coding (SAC) based on the interval splitting arithmetic coding (ISAC) and a series of permutations. In the current work, we study the security of the SAC under an adaptive chosen-ciphertext attack. It is shown that the key vectors used in the codeword permutation step can be recovered with complexity O(N), where N is the symbol sequence length. After getting these key vectors, we can remove the codeword permutation step, and the resulting system has already been shown to be insecure in the original paper. This implies that the SAC is not suitable for the applications where the attacker can have access to the decoder. In addition, we discuss a method to jointly enhance the security and the performance of the SAC.     

Microwave Thermal Emission from Periodic Surfaces

The emissivity of a periodic surface is calculated from one minus the reflectivity by using the reciprocity principle. The reflectivity consists of the sum of all scattered power as determined from the modal theory which obeys both the principle of reciprocity and the principle of energy conservation. The theoretical results are matched to experimental data obtained from brightness temperature measurements as functions of viewing angle for soil moisture in plowed fields. The threshold phenomenon with regard to the appearing and disappearing of modes in their contributions to the scattered field amplitudes is discussed in connection with the theoretical results. It is shown that this approach for calculating the emissivity greatly reduces computational efforts by requiring substantially smaller matrix sizes.     

ZnBr2–Ph4PI as highly efficient catalyst for cyclic carbonates synthesis from terminal epoxides and carbon dioxide

The catalyst systems composed of ZnBr₂ and different phosphonium salts were examined for solvent-free synthesis of cyclic carbonates from CO₂ and terminal epoxides under mild conditions. Among the catalysts investigated, ZnBr₂–Ph₄PI was found to be the best while those of ZnBr₂–phosphine oxide (Bu₃PO or Ph₃PO) show no catalytic effect. It is apparent that the halide ions of phosphonium salts have an essential role to play in the reaction. The catalytic activity of ZnBr₂–Ph₄PI increases with a rise of Ph₄PI to ZnBr₂ molar ratio up to 6, above which there is little change in catalytic activity. We observed that with a rise in ZnBr₂ to Ph₄PI molar ratio, there is increase in epoxide conversion but decline in TOF_PO (estimated based on the site number of Zn²⁺). The effect of water on the reaction was investigated for the first time. We found that the presence of even a trace amount of water would result in a marked decline in reactivity, and the observation provides a valid explanation for why reproducibility of results is poor among researchers so far. The influences of other parameters such as reaction temperature and CO₂ pressure on the catalytic performance of ZnBr₂–PPh₄I were also studied. It is shown that the catalyst is sensitive to reaction temperature, and a rise of reaction temperature up to 130 °C favors the formation of cyclic carbonates. We observed that activity increases with rise in CO₂ pressure and reaches a maximum at an initial CO₂ pressure of 2.5 MPa. Moreover, a plausible reaction mechanism has been proposed.     

Gold Nanocages for Biomedical Applications

Nanostructured materials provide a promising platform for early cancer detection and treatment. Here we highlight recent advances in the synthesis and use of Au nanocages for such biomedical applications. Gold nanocages represent a novel class of nanostructures, which can be prepared via a remarkably simple route based on the galvanic replacement reaction between Ag nanocubes and HAuCl(4). The Au nanocages have a tunable surface plasmon resonance peak that extends into the near-infrared, where the optical attenuation caused by blood and soft tissue is essentially negligible. They are also biocompatible and present a well-established surface for easy functionalization. We have tailored the scattering and absorption cross-sections of Au nanocages for use in optical coherence tomography and photothermal treatment, respectively. Our preliminary studies show greatly improved spectroscopic image contrast for tissue phantoms containing Au nanocages. Our most recent results also demonstrate the photothermal destruction of breast cancer cells in vitro by using immuno-targeted Au nanocages as an effective photo-thermal transducer. These experiments suggest that Au nanocages may be a new class of nanometer-sized agents for cancer diagnosis and therapy.     

Human listeners provide insights into echo features used by dolphins (Tursiops truncatus) to discriminate among objects.

Echolocating bottlenose dolphins (Tursiops truncatus) discriminate between objects on the basis of the echoes reflected by the objects. However, it is not clear which echo features are important for object discrimination. To gain insight into the salient features, the authors had a dolphin perform a match-to-sample task and then presented human listeners with echoes from the same objects used in the dolphin's task. In 2 experiments, human listeners performed as well or better than the dolphin at discriminating objects, and they reported the salient acoustic cues. The error patterns of the humans and the dolphin were compared to determine which acoustic features were likely to have been used by the dolphin. The results indicate that the dolphin did not appear to use overall echo amplitude, but that it attended to the pattern of changes in the echoes across different object orientations. Human listeners can quickly identify salient combinations of echo features that permit object discrimination, which can be used to generate hypotheses that can be tested using dolphins as subjects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of PDE4 inhibitors on zymosan-induced IL-8 release from human neutrophils: synergism with prostanoids and salbutamol

1. The activation of neutrophils with particulate stimuli such as zymosan induces the generation of the C-X-C chemokine interleukin (IL)-8. There is evidence that neutrophil derived IL-8 plays an important role in human diseases such as the adult respiratory distress syndrome. In the present study, we examined the effects of cyclic AMP elevating agents on the ability of human neutrophils to generate IL-8 in response to zymosan particles. 2. The PDE4 inhibitor rolipram had limited effect on zymosan-induced IL-8 generation. In contrast, the PDE4 inhibitors RP 73401 and SB 207499 concentration-dependently suppressed IL-8 generation. The potency of these inhibitors was RP 73401 > SB 207499 > rolipram which is correlated with their rank order of potency at inhibiting the catalytic site of purified neutrophil PDE4. Pretreatment of neutrophils with the PDE3 inhibitor ORG 9935 or the PDE5 inhibitor zaprinast had no effect on IL-8 generation. 3. The prostanoids prostaglandin E1 (PGE1) and PGE2 inhibited zymosan-induced IL-8 release from neutrophils in a dose-dependent manner, in response to 10(-5) M PGE1 and PGE2 inhibiting IL-8 generation by 89% and 75%, respectively. Similarly, the beta2-adrenoceptor agonist salbutamol also inhibited IL-8 generation, but it was less effective than the prostanoids. 4. Significant synergism between prostanoids or salbutamol and the PDE4 inhibitors to inhibit IL-8 generation was observed. In contrast, there was no significant synergism between PGE2 and the PDE3 inhibitor ORG 9935 or the PDE5 inhibitor zaprinast. 5. In order to evaluate the potential role of protein kinase A in mediating the inhibitory effects of cyclic AMP-elevating agents, we used the protein kinase A inhibitors, H 89 and KT 5720. Pretreatment of neutrophils with these drugs completely reversed the inhibitory effects of a combination treatment with rolipram and PGE2 on zymosan-induced IL-8 release. 6. Microscopic examination revealed that most neutrophils contained one or more zymosan particles and that combination treatment with rolipram and PGE2 noticeably reduced the number of ingested particles. Moreover, there was a significant reduction in the percentage of neutrophils which ingested three or more zymosan particles. 7. Thus, our results demonstrate that cyclic AMP-elevating agents modulate the ability of neutrophils to generate IL-8 in response to a particulate stimulus. However, these agents also modulate the ability of neutrophils to phagocytose zymosan particles. Whether this effect will translate into inhibition of the ability of neutrophils to deal with infectious agents needs to be investigated further.     

Functional MRI study of PASAT in normal subjects

The paced auditory serial addition test (PASAT) is routinely used to evaluate the cognitive part of the multiple sclerosis functional composite (MSFC) score, the new reference index of patient disability. PASAT is sensitive to subtle cognitive impairment related to MS, although the cognitive components of this test still remain unclear. In order to better characterize brain systems involved during this complex task, functional magnetic resonance imaging (fMRI) experiments were conducted during PASAT in a population of ten normal subjects. The paradigm consisted of a series of 61 single-digit numbers delivered every 3 s. After each number, subjects were asked to overt vocalize the result of the addition of the two last numbers heard. A control task consisting of the repetition of the same series of single-digit numbers was used. Statistical group analysis was performed using the random effect procedure (SPM 99). Cortical activation was observed in the left prefontal cortex, the supplementary motor area, the lateral premotor cortex, the cingulate gyrus, the left parietal lobe, the left superior temporal gyrus, the left temporal pole, and visual associative areas. fMRI activations underlying PASAT were consistent with an involvement of verbal working memory and the semantic memory retrieval network which could be related to arithmetic fact retrieval. This study on normal subjects could provide a base for the understanding of the potential abnormal cortical activation in MS patients performing this test for a cognitive evaluation.This revised version was published in March 2005 with corrections to the history.     

Field-programmable logic devices with optical input-output

A field-programmable logic device (FPLD) with optical I/O is described. FPLD's with optical I/O can have their functionality specified in the field by means of downloading a control-bit stream and can be used in a wide range of applications, such as optical signal processing, optical image processing, and optical interconnects. Our device implements six state-of-the-art dynamically programmable logic arrays (PLA's) on a 2 mm x 2 mm die. The devices were fabricated through the Lucent Technologies-Advanced Research Projects Agency-Consortium for Optical and Optoelectronic Technologies in Computing (Lucent/ARPA/COOP) workshop by use of 0.5-mum complementary metal-oxide semiconductor-self-electro-optic device technology and were delivered in 1998. All devices are fully functional: The electronic data paths have been verified at 200 MHz, and optical tests are pending. The device has been programmed to implement a two-stage optical switching network with six 4 x 4 crossbar switches, which can realize more than 190 x 10(6) unique programmable input-output permutations. The same device scaled to a 2 cm x 2 cm substrate could support as many as 4000 optical I/O and 1 Tbit/s of optical I/O bandwidth and offer fully programmable digital functionality with approximately 110,000 programmable logic gates. The proposed optoelectronic FPLD is also ideally suited to realizing dense, statically reconfigurable crossbar switches. We describe an attractive application area for such devices: a rearrangeable three-stage optical switch for a wide-area-network backbone, switching 1000 traffic streams at the OC-48 data rate and supporting several terabits of traffic.