An initial assessment of the biocompatibility of crab shell for bone tissue engineering

There is a kinship that exists among biologically derived hard tissues. This inter-relatedness is expressed via comparable mechanisms for organic matrix organization and biomineralization processes. The ability to use biogenic hard tissues such as coral and nacre in augmentation of damaged bone tissue further attests to the unique bonds which are shared by hard tissues in nature. Crab shell cuticle is another candidate material for enhancing the healing and remodeling of bone. A comparison of the unique chemical and physical characteristics of bone and crab shell with a focus on the respective organic matrices and mineral phases serves as the focus for this study of crushed crab shell as an osteogenic material. L929 murine fibroblasts were used to assess the initial biocompatibility of crab shell granules. Short term subcutaneous implantation of demineralized crab shell granules in the abdominal region of 28 day old Sprague-Dawley rats resulted in a high level of localized monocyte and macrophage like cells that digested the shell granules in a manner reminiscent of osteoclasts. The presence of early stage collagen fiber bundles with interspersed mineral crystals within the first week suggests that crab shell exhibits osteogenic properties.     

稀土金属硅化物的场发射

用金属蒸发真空弧离子注入方法制备了各种稀土金属的硅化物,定义1μA/cm2时的电场为开启电场,发现它们的开启电场在15～20V/μm之间.用电子束对其进行退火处理后,开启电场降到10V/μm以下,而场发射密度可以提高一个数量级.它们良好的场发射性能归因于稀土金属硅化物本身热稳定性好,功函数低.用FN理论对场发射的机理进行了分析,发现其FN曲线明显分成了两段,这可能是因为在场发射过程中引起的温度效应.     

Overconfidence effects in category learning: A comparison of connectionist and exemplar memory models.

Exemplar and connectionist models were compared on their ability to predict overconfidence effects in category learning data. In the standard task, participants learned to classify hypothetical patients with particular symptom patterns into disease categories and reported confidence judgments in the form of probabilities. The connectionist model asserts that classifications and confidence are based on the strength of learned associations between symptoms and diseases. The exemplar retrieval model (ERM) proposes that people learn by storing examples and that their judgments are often based on the first example they happen to retrieve. Experiments 1 and 2 established that overconfidence increases when the classification step of the process is bypassed. Experiments 2 and 3 showed that a direct instruction to retrieve many exemplars reduces overconfidence. Only the ERM predicted the major qualitative phenomena exhibited in these experiments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

40—BLENDING WOOL FOR YIELD-TESTING PART II: EXAMINATION OF A BLENDER FOR SCOURED SUB-SAMPLES

An investigation is reported in which a small ‘spherical’ blender was examined to ascertain if its use reduced the within-sub-sample component of total alkali-insolubles. Although this proved to be the case, the blender modified the alkali solubility of the vegetable matter, so that the recovered mass of alkali-insolubles was decreased.

Use of the spherical blender for scoured sub-samples that are to be tested for vegetable-matter content by the standard method (IWTO–19–76(E)) is not therefore recommended.     

A Sub-10 nm Vertical Organic/Inorganic Hybrid Transistor for Pain-Perceptual and Sensitization-Regulated Nociceptor Emulation

Pain-perceptual nociceptors (PPN) are essential sensory neurons that recognize harmful stimuli and can empower the human body to react appropriately and perceive precisely unusual or dangerous conditions in the real world. Furthermore, the sensitization-regulated nociceptors (SRN) can greatly assist pain-sensitive human to reduce pain sensation by normalizing hyperexcitable central neural activity. Therefore, the implementation of PPNs and SRNs in hardware using emerging nanoscale devices can greatly improve the efficiency of bionic medical machines by giving them different sensitivities to external stimuli according to different purposes. However, current most-normal organic/oxide transistors face a great challenge due to channel scaling, especially in the sub-10 nm channel technology. Here, a sub-10 nm indium-tin-oxide transistor with an ultrashort vertical channel as low as ≈3 nm, using sodium alginate bio-polymer electrolyte as gate dielectric, is demonstrated. This device can emulate important characteristics of PPN such as pain threshold, memory of prior injury, and pain sensitization/desensitization. Furthermore, the most intriguing character of SRN can be achieved by tuning the channel thickness. The proposed device can open new avenues for the fascinating applications of next-generation neuromorphic brain-like systems, such as bio-inspired electronic skins and humanoid robots.     

Image restoration of compressed image using classified vector quantization

To reduce communication bandwidth or storage space, image compression is needed. However, the subjective quality of compressed images may be unacceptable and the improvement of quality for compressed images may be desirable. This paper extends and modifies classified vector quantization (CVQ) to improve the quality of compressed images. The process consists of two phases: the encoding phase and the decoding phase. The encoding procedure needs a codebook for the encoder, which transforms a compressed image to a set of codeword-indices. The decoding phase also requires a different codebook for the decoder, which enhances a compressed image from a set of codeword-indices. Using CVQ to improve a compressed image's quality is different from the existing algorithm, which cannot reconstruct the high frequency components for compressed images. The experimental results show that the image quality is improved dramatically. For images in the training set, the improvement of PSNR is about 3 dB. For images, which are outside the training set, the improvement of PSNR is about 0.57 dB, which is comparable to the existing method.     

Some long time delay sliding mode control approaches

This paper presents a combined approach of predictive structures with sliding mode control (SMC). Control schemes have been proposed looking for performance and robustness improvement. These structures were designed for processes that can be approximated either by a first order plus time delay or an integral first order plus time delay model broadly used on chemical processes. The proposed schemes were tested for performance and robustness against set point changes and disturbances as compared with classical approaches.     

Modeling the point-spread function in helium-ion lithography

We present here a hybrid approach to modeling helium-ion lithography that combines the power and ease-of-use of the Stopping and Range of Ions in Matter (SRIM) software with the results of recent work simulating secondary electron (SE) yield in helium-ion microscopy. This approach traces along SRIM-produced helium-ion trajectories, generating and simulating trajectories for SEs using a Monte Carlo method. We found, both through simulation and experiment, that the spatial distribution of energy deposition in a resist as a function of radial distance from beam incidence, i.e. the point spread function, is not simply a sum of Gauss functions.     

An e-patient’s End-user community (EUCY): The value added of social network applications

Decreasing revenues and increasing expenses has led many healthcare organizations to adopt newer technological applications in order to address the informational needs of their patients. One such adoption technique is to develop a more robust e-patient environment. Health care organizations may increase their effectiveness in meeting the needs of a growing e-patient population through the implementation of high-quality social networking applications such as Twitter. These applications may help to support and maintain a valuable and informed community. A literature review identifies three characteristics that have an impact on information exchange inherent to social networks: number of members, contact frequency, and type of knowledge. Data from a case study of a juvenile diabetic using Twitter helps to demonstrate these aforementioned characteristics. A framework is developed that may be used by health care organizations to better align social network objectives with expectations of an End user community (EUCY). Managerial implications of this study are discussed that can help information technology professionals as well as health administrators when implementing social networks.     

The grafting of methyl methacrylate onto ultrahigh molecular weight polyethylene fiber by plasma and UV treatment

In this study, ultrahigh molecular weight polyethylene (UHMWPE) fibers were treated with a gas plasma of argon for 5 min. The plasma-treated UHMWPE fibers were put into a methyl methacrylate solution with n-hexane or chloroform as the solvent and irradiated with a UV lamp. The UV irradiation time was changed. The surface topography that had a significant change on the fiber was seen by scanning electron microscopy. Infrared spectra (IR) and electron spectroscopy for chemical analysis (ESCA) were also studied to probe the surface atomic chemistry and to identify the functional groups and their relative changes with treatment conditions. The grafting content was estimated by the titration of esterfication method. It was found that the grafting amount for the system with chloroform as the solvent is larger than that for the system with n-hexane as the solvent. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:365–371, 1997