A Reconstruction Method Based on AL0FGD for Compressed Sensing in Border Monitoring WSN System

In this paper, to monitor the border in real-time with high efficiency and accuracy, we applied the compressed sensing (CS) technology on the border monitoring wireless sensor network (WSN) system and proposed a reconstruction method based on approximately l₀ norm and fast gradient descent (AL0FGD) for CS. In the frontend of the system, the measurement matrix was used to sense the border information in a compressed manner, and then the proposed reconstruction method was applied to recover the border information at the monitoring terminal. To evaluate the performance of the proposed method, the helicopter sound signal was used as an example in the experimental simulation, and three other typical reconstruction algorithms 1)split Bregman algorithm, 2)iterative shrinkage algorithm, and 3)smoothed approximate l₀ norm (SL0), were employed for comparison. The experimental results showed that the proposed method has a better performance in recovering the helicopter sound signal in most cases, which could be used as a basis for further study of the border monitoring WSN system.     

Aptamer Selection Express: A Novel Method for Rapid Single-Step Selection and Sensing of Aptamers

Here we describe a new DNA capture element (DCE) sensing system, based on the quenching and dequenching of a double-stranded aptamer. This system shows very good sensitivity and thermal stability. While quenching, dequenching, and separating the DCE systems made from different aptamers (all selected by SELEX), an alternative method to rapidly select aptamers was developed—the Aptamer Selection Express (ASExp). This process has been used to select aptamers against different types of targets (Bacillus anthracis spores, Bacillus thuringiensis spores, MS-2 bacteriophage, ovalbumin, and botulinum neurotoxin). The DCE systems made from botulinum neurotoxin aptamers selected by ASExp have been investigated. The results of this investigation indicate that ASExp can be used to rapidly select aptamers for the DCE sensing system.     

Interpolated Compressed Sensing for 2D Multiple Slice Fast MR Imaging

Sparse MRI has been introduced to reduce the acquisition time and raw data size by undersampling the k-space data. However, the image quality, particularly the contrast to noise ratio (CNR), decreases with the undersampling rate. In this work, we proposed an interpolated Compressed Sensing (iCS) method to further enhance the imaging speed or reduce data size without significant sacrifice of image quality and CNR for multi-slice two-dimensional sparse MR imaging in humans. This method utilizes the k-space data of the neighboring slice in the multi-slice acquisition. The missing k-space data of a highly undersampled slice are estimated by using the raw data of its neighboring slice multiplied by a weighting function generated from low resolution full k-space reference images. In-vivo MR imaging in human feet has been used to investigate the feasibility and the performance of the proposed iCS method. The results show that by using the proposed iCS reconstruction method, the average image error can be reduced and the average CNR can be improved, compared with the conventional sparse MRI reconstruction at the same undersampling rate.     

Balanced Sparse Model for Tight Frames in Compressed Sensing Magnetic Resonance Imaging

Compressed sensing has shown to be promising to accelerate magnetic resonance imaging. In this new technology, magnetic resonance images are usually reconstructed by enforcing its sparsity in sparse image reconstruction models, including both synthesis and analysis models. The synthesis model assumes that an image is a sparse combination of atom signals while the analysis model assumes that an image is sparse after the application of an analysis operator. Balanced model is a new sparse model that bridges analysis and synthesis models by introducing a penalty term on the distance of frame coefficients to the range of the analysis operator. In this paper, we study the performance of the balanced model in tight frame based compressed sensing magnetic resonance imaging and propose a new efficient numerical algorithm to solve the optimization problem. By tuning the balancing parameter, the new model achieves solutions of three models. It is found that the balanced model has a comparable performance with the analysis model. Besides, both of them achieve better results than the synthesis model no matter what value the balancing parameter is. Experiment shows that our proposed numerical algorithm constrained split augmented Lagrangian shrinkage algorithm for balanced model (C-SALSA-B) converges faster than previously proposed algorithms accelerated proximal algorithm (APG) and alternating directional method of multipliers for balanced model (ADMM-B).     

A Novel Method for Coral Explant Culture and Micropropagation

We describe here a method for the micropropagation of coral that creates progeny from tissue explants derived from a single polyp or colonial corals. Coral tissue explants of various sizes (0.5?C2.5?mm in diameter) were manually microdissected from the solitary coral Fungia granulosa. Explants could be maintained in an undeveloped state or induced to develop into polyps by manipulating environmental parameters such as light and temperature regimes, as well as substrate type. Fully developed polyps were able to be maintained for a long-term in a closed sea water system. Further, we demonstrate that mature explants are also amenable to this technique with the micropropagation of second-generation explants and their development into mature polyps. We thereby experimentally have established coral clonal lines that maintain their ability to differentiate without the need for chemical induction or genetic manipulation. The versatility of this method is also demonstrated through its application to two other coral species, the colonial corals Oculina patigonica and Favia favus.     

A Novel Anti-Influenza Copper Oxide Containing Respiratory Face Mask

Background

Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties.

Methodology/Principal Findings

We demonstrate that impregnation of copper oxide into respiratory protective face masks endows them with potent biocidal properties in addition to their inherent filtration properties. Both control and copper oxide impregnated masks filtered above 99.85% of aerosolized viruses when challenged with 5.66±0.51 and 6.17±0.37 log₁₀TCID₅₀ of human influenza A virus (H1N1) and avian influenza virus (H9N2), respectively, under simulated breathing conditions (28.3 L/min). Importantly, no infectious human influenza A viral titers were recovered from the copper oxide containing masks within 30 minutes (≤0.88 log₁₀TCID₅₀), while 4.67±1.35 log₁₀TCID₅₀ were recovered from the control masks. Similarly, the infectious avian influenza titers recovered from the copper oxide containing masks were ≤0.97±0.01 log₁₀TCID₅₀ and from the control masks 5.03±0.54 log₁₀TCID₅₀. The copper oxide containing masks successfully passed Bacterial Filtration Efficacy, Differential Pressure, Latex Particle Challenge, and Resistance to Penetration by Synthetic Blood tests designed to test the filtration properties of face masks in accordance with the European EN 14683:2005 and NIOSH N95 standards.

Conclusions/Significance

Impregnation of copper oxide into respiratory protective face masks endows them with potent anti-influenza biocidal properties without altering their physical barrier properties. The use of biocidal masks may significantly reduce the risk of hand or environmental contamination, and thereby subsequent infection, due to improper handling and disposal of the masks.     

Self-Navigation with Compressed Sensing for 2D Translational Motion Correction in Free-Breathing Coronary MRI: A Feasibility Study

Purpose

Respiratory motion correction remains a challenge in coronary magnetic resonance imaging (MRI) and current techniques, such as navigator gating, suffer from sub-optimal scan efficiency and ease-of-use. To overcome these limitations, an image-based self-navigation technique is proposed that uses “sub-images” and compressed sensing (CS) to obtain translational motion correction in 2D. The method was preliminarily implemented as a 2D technique and tested for feasibility for targeted coronary imaging.

Methods

During a 2D segmented radial k-space data acquisition, heavily undersampled sub-images were reconstructed from the readouts collected during each cardiac cycle. These sub-images may then be used for respiratory self-navigation. Alternatively, a CS reconstruction may be used to create these sub-images, so as to partially compensate for the heavy undersampling. Both approaches were quantitatively assessed using simulations and in vivo studies, and the resulting self-navigation strategies were then compared to conventional navigator gating.

Results

Sub-images reconstructed using CS showed a lower artifact level than sub-images reconstructed without CS. As a result, the final image quality was significantly better when using CS-assisted self-navigation as opposed to the non-CS approach. Moreover, while both self-navigation techniques led to a 69% scan time reduction (as compared to navigator gating), there was no significant difference in image quality between the CS-assisted self-navigation technique and conventional navigator gating, despite the significant decrease in scan time.

Conclusions

CS-assisted self-navigation using 2D translational motion correction demonstrated feasibility of producing coronary MRA data with image quality comparable to that obtained with conventional navigator gating, and does so without the use of additional acquisitions or motion modeling, while still allowing for 100% scan efficiency and an improved ease-of-use. In conclusion, compressed sensing may become a critical adjunct for 2D translational motion correction in free-breathing cardiac imaging with high spatial resolution. An expansion to modern 3D approaches is now warranted.     

A Novel Method for Detection of Endo-Xyloglucan Transferase

A new approach has been developed for quantification of theactivity of endo-xyloglucan transferase, a novel enzyme thatmediates the transfer of a segment of one xyloglucan moleculeto another xyloglucan molecule. Purified xyloglucans with definedmolecular-weight distributions and their fluorescent derivatives(pyridylamino xyloglucans) were used as substrates for the enzymaticreaction. The transferase activity was quantified by monitoringchanges in molecular-weight distributions of substrates by analkali compatible gel permeation chromatographic system, equippedwith a pulsed amperometric detector and a fluorescence detector.This new method was applied to the rapid detection and characterizationof a novel transferase derived from plant tissues. (Received February 28, 1992; Accepted September 28, 1992)     

A Novel Amplified Enzymatic Assay Method for Hypoxanthine

A sensitive and rapid enzymatic assay for hypoxanthine, using a Clark oxygen electrode as sensor, is proposed. In the presence of sodium sulfite, oxidation of hypoxanthine by milk xanthine oxidase caused very rapid oxygen consumption in excess of the stoichiometric requirement for hypoxanthine oxidation. Hypoxanthine from 0.5 to 10 μM can be assayed within a few minutes by addition of 25 mM sodium sulfite to the reaction mixture. This assay proved to be over 10-times more sensitive and much more rapid than the control method without sulfite.     

A Novel Screening Method for Isolating Exopolysaccharide-Deficient Mutants

A screening method based on differential staining of the wild type and exopolysaccharide-deficient mutants of Rhizobium (Sinorhizobium) meliloti by the lipophilic dye Sudan Black B is described. Mutants defective in the production of either succinoglycan or EPS II (galactoglucan) were isolated by using this method, which might also prove useful for isolating exopolysaccharide-defective derivatives of other bacteria.     

A Novel Amplified Enzymatic Assay Method for Hypoxanthine

A sensitive and rapid enzymatic assay for hypoxanthine, using a Clark oxygen electrode as sensor, is proposed. In the presence of sodium sulfite, oxidation of hypoxanthine by milk xanthine oxidase caused very rapid oxygen consumption in excess of the stoichiometric requirement for hypoxanthine oxidation. Hypoxanthine from 0.5 to 10 μM can be assayed within a few minutes by addition of 25 mM sodium sulfite to the reaction mixture. This assay proved to be over 10-times more sensitive and much more rapid than the control method without sulfite.     

多通道神经元锋电位检测和分类的新方法

大脑神经元胞外单细胞动作电位(即锋电位)的检测和分类是提取神经元脉冲序列、研究神经系统信息处理机制的关键．为了提高锋电位的检出率和分类的正确性,设计了一种处理多通道锋电位记录信号的算法,用于分析微电极阵列记录的大鼠海马神经元锋电位信号,电极阵列上的测量点排列紧密,4个通道可以同时记录到来自相同神经元的信号．该算法首先利用一种多通道阈值检测法检出四通道记录信号中的锋电位,然后利用一种基于复合锋电位的主成分特征参数分类法将锋电位分类．仿真数据和实验记录信号的检验结果表明：与相应的单通道算法相比,该算法的锋电位检出率和分类的正确性显著提高,并且可以增加单次实验测得的神经元数目．因此,该算法为实现神经元锋电位的自动检测提供了一种简单有效的新 方法．     

基于波长寻址的表面等离子体共振传感技术

本文提出了基于光谱扫描技术的非机械扫描的表面等离子体共振(SPR)传感技术,采用白光为SPR激发光源,通过单色仪控制入射光的波长实现光谱寻址,在保证灵敏度和动态范围的同时,使系统在整个动态范围内具有较好的线性,简化了传感器结构。理论分析了光谱扫描SPR传感技术的灵敏度和动态范围,搭建了实验系统,并测量了不同浓度的酒精水混合溶液的SPR信号变化。结果表明:系统折射率测量范围为1.30-1.38,灵敏度可达3.1×105RIU。     

近红外无创伤血糖测量的组织光学基础研究

人体血糖浓度无创伤测量是当今学术界和医学界普遍关注的课题。在分析了血糖浓度无创伤测量的意义、现有的测量方法及其进展后,从组织光学角度分析血糖浓度无创伤测量中包含的研究内容,并根据当前的研究现状,提出血糖浓度无创伤测量所存在的问题。通过组织光学角度对血糖浓度无创伤测量方法的剖析,更加明确血糖测量的研究任务,有望促使其更进一步的发展以及血液中其他成分的无创测量。     

A Novel Generalized Ridge Regression Method for Quantitative Genetics

As the molecular marker density grows, there is a strong need in both genome-wide association studies and genomic selection to fit models with a large number of parameters. Here we present a computationally efficient generalized ridge regression (RR) algorithm for situations in which the number of parameters largely exceeds the number of observations. The computationally demanding parts of the method depend mainly on the number of observations and not the number of parameters. The algorithm was implemented in the R package bigRR based on the previously developed package hglm. Using such an approach, a heteroscedastic effects model (HEM) was also developed, implemented, and tested. The efficiency for different data sizes were evaluated via simulation. The method was tested for a bacteria-hypersensitive trait in a publicly available Arabidopsis data set including 84 inbred lines and 216,130 SNPs. The computation of all the SNP effects required <10 sec using a single 2.7-GHz core. The advantage in run time makes permutation test feasible for such a whole-genome model, so that a genome-wide significance threshold can be obtained. HEM was found to be more robust than ordinary RR (a.k.a. SNP-best linear unbiased prediction) in terms of QTL mapping, because SNP-specific shrinkage was applied instead of a common shrinkage. The proposed algorithm was also assessed for genomic evaluation and was shown to give better predictions than ordinary RR.     

A Novel Preparation Method for Organogels: High-Speed Homogenization and Micro-irradiation

The aim of this work was to prepare organogels of Carbopol 974P NF (C974) in PEG 400 by using a novel technique, high-speed homogenization followed by microwave heating. Triclosan (TCS) was used as a model drug. C974, at concentrations ranging between 2% and 4%, was dispersed in 25 ml of PEG 400, and the dispersion was homogenised for 5 min at 24,000 rpm. The dispersion was either heated at 80°C in water bath under mechanic stirring at 200 rpm or exposed to micro-irradiation (1,200 W/1 h) for 2 min. The formulations prepared with both methods performed a well-structured gel matrix characteristic at 3% and 4% of C974 concentrations. As the concentrations of the polymer increased, the elastic properties also increased. The viscosity profiles indicated a shear-thinning system. DSC data revealed that TCS was dissolved in gel. Skin accumulation ability of TCS had been improved by these novel organogels regardless of the preparation method. TCS was still microbiologically effective after the microwave process was applied. It was determined that microwave heating is a suitable method to obtain C974 organogels. This novel production technique developed might be promising especially in industrial scale when the dramatic reduction in the preparation time and energy were considered.     

Plastic Compressed Collagen as a Novel Carrier for Expanded Human Corneal Endothelial Cells for Transplantation

Current treatments for reversible blindness caused by corneal endothelial cell failure involve replacing the failed endothelium with donor tissue using a one donor-one recipient strategy. Due to the increasing pressure of a worldwide donor cornea shortage there has been considerable interest in developing alternative strategies to treat endothelial disorders using expanded cell replacement therapy. Protocols have been developed which allow successful expansion of endothelial cells in vitro but this approach requires a supporting material that would allow easy transfer of cells to the recipient. We describe the first use of plastic compressed collagen as a highly effective, novel carrier for human corneal endothelial cells. A human corneal endothelial cell line and primary human corneal endothelial cells retained their characteristic cobblestone morphology and expression of tight junction protein ZO-1 and pump protein Na+/K+ ATPase α1 after culture on collagen constructs for up to 14 days. Additionally, ultrastructural analysis suggested a well-integrated endothelial layer with tightly opposed cells and apical microvilli. Plastic compressed collagen is a superior biomaterial in terms of its speed and ease of production and its ability to be manipulated in a clinically relevant manner without breakage. This method provides expanded endothelial cells with a substrate that could be suitable for transplantation allowing one donor cornea to potentially treat multiple patients.     

A Novel Method for Extracting Protoplasts from Large Brown Algae

Protoplasts have been isolated without the application of walldegrading enzymes from three large brown algal species: Macrocystisangustifolia, Ecklonia radiata and Durvillaea potatorum. Thecentral feature of this new protocol is the removal of wall-boundcalcium by substitution with sodium from the isolation medium.The new protocol is specific for cortex and inner meristodermcell walls with highest yields obtained from meristematic oryoung tissue. Protoplasts, extracted with this method, are approximately5–10 µm in diameter with viability estimates rangingfrom 73–86%. Consistent yields of 10⁷ protoplasts g^–1fresh weight have been obtained within 2–3 for all threespecies and this compares favourably with yields achieved usinga conventional enzyme-based system. Key words: Brown algae, protoplasts, alginate, calcium, enzymes     

基于图像配准分析物种进化关系的新方法

图像配准是图像处理的一个重要技术,可用于分析两幅图像之间的相似度。本文提出了一种基于图像配准分析物种进化关系的新方法:首先利用一阶马尔可夫链方法计算不同基因组序列的寡聚核苷酸转移概率矩阵;然后将转移概率矩阵转换为彩色图像矩阵,并绘制物种两两之间彩色图像矩阵的联合直方图;最后分析联合直方图点集的分布情况,引入直方图点集的散度公式,将其作为相似性测度的标准,从而鉴定物种亲缘关系的远近。100种细菌全基因组的计算结果表明,相较于单基因法或基于基因组寡聚核苷酸频率组分差异信息的方法,本文提出的新方法具有更高的准确度和分辨力,它不仅能够很好地分辨科以下的分类单元,而且对科以上的分类单元同样具有较好的区分效果。该方法有望发展成为物种鉴定及系统发育推断的有效手段。