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At present, the accuracy of strain measurement using a common optical extensometer with 2D digital image correlation is not sufficient for experimental applications due to the effect of out-of-plane motion. Therefore, this paper proposes a dual-reflector imaging method to improve the accuracy of strain measurement when using a common optical extensometer, with which the front and rear surfaces of a specimen can be simultaneously recorded in the sensor plane of a digital camera. By averaging the strain in two optical extensometers formed on the front and rear surfaces of a specimen, the effect of any slight out-of-plane motion can be eliminated and therefore the strain measurement accuracy can also be improved. Uniaxial tensile tests with an Al-alloy specimen, including static loading and continuous loading, were conducted to validate the feasibility and reliability of the proposed method. The strain measurement results obtained with the proposed method and those obtained with an electrical-resistance strain gauge were found to be in good agreement. The average errors of the proposed method for the two continuous loading tests were found to be 8 ± 10 μe and −6 ± 8 μe. Given that no correction sheet or compensation specimen is required, the proposed method is easy to implement and thus especially suitable for determining the mechanical properties of brittle materials due to the high level of accuracy with which strain can be measured.

In industrial measurements and online monitoring, full-field and high-efficiency deformation analysis has been increasingly important and highly demanded in recent years. In this paper, a fast three-dimensional digital image correlation (3D-DIC) method was proposed to implement real-time measurement. Two improvements were suggested to accelerate the computation speed without sacrificing the accuracy. First, an efficient inverse compositional Gauss-Newton (IC-GN) algorithm was developed to avoid redundant computation. Moreover, a seed point-based parallel method was extended for 3D-DIC to achieve parallel computation and faster convergence speed. The detailed process of the real-time measurement using the proposed method was also introduced. Benefiting from the efficient IC-GN algorithm and parallel processing software we developed, full-field, real-time 3D deformation monitoring was realized at a frame rate of 10 frames/s with resolution of 5000 points per frame. For validation, the displacement field of a four-point bending beam was determined by the real-time 3D-DIC. As an application, the real-time human pulse diagnosis was also performed based on the presented technique. Experimental results verify that the proposed real-time 3D-DIC is practicable and effective for traditional Chinese medicine.

To destroy a country's physical electric power infrastructure by attacking its control system through cyber means, has become an important way to weaken a country's war power. Along with the construction of next generation smart grid, development of the internet of things and appearance of system of systems(henceforth, SOS) warfare based on information systems, the complicated control networks system would confront more and more threat of cyber attack. we design the main structure and key arithmetic of the model, based on the physical electric power infrastructure whose cyber and physical system is close interdependent in order to provide theoretic reference to the analyzing and evaluating the cascading effects from increasing cyber attack to physic system. Preliminary experiments show that these structures and algorithms are reasonable and feasible.

In fringe projection, the CCD camera and the projector are often placed at equal height. In this paper, we will study the calibration of an unequal arrangement of the CCD camera and the projector. The principle of fringe projection with two-dimensional digital image correlation to acquire the profile of object surface is described in detail. By formula derivation and experiment, the linear relationship between the out-of-plane calibration coefficient and the y coordinate is clearly found. To acquire the three-dimensional (3D) information of an object correctly, this paper presents an effective calibration method with linear least-squares fitting, which is very simple in principle and calibration. Experiments are implemented to validate the availability and reliability of the calibration method.

Aiming at the question that the existence of zero-order image has certain effect on the quality of reconstructed images in digital holography, by analysis of spectrum characteristic as well as record and represent theory, two digital image processing algorithm — differential substitution and the FIR filter are proposed for zero-order image elimination in digital holography. These two methods are free of any other extra equipment, recording only one hologram. The theoretical analysis, digital simulation and experiment verifying results presented that the zero-order image is eliminated and the quality of reconstructed image enhanced. The methods which are proved to be fast and simple can be used in the real time inspection.

This article analyzed environmental economic problems of regions by which the economic growth model for multi-department endogenesis included environmental factors, sustainable development possibilities of regional economics and related optimal control strategies. It provided some viable models and methods for an analysis of regional environmental economics. Based on the economic growth model of multi-department endogenesis, developed and developing regional environmental economic optimal models with environmental factors were built respectively against the developed and developing regional characteristics. When optimal solution existed and settled, through solving solution to growth rate of some important economic variables on the stable condition, it analyzed environmental economic problems in developed and developing regions, and made a primary analysis of the optimal control strategy for sustainable development.

In this paper, a test based on the wavelet transform for instantaneous three dimensional (3D) Carp tail fin profile measurements and analysis the kinematics of Carp tail fin method was proposed to understand the function of the tail fin. This experiment method is used in cruising carp. Projecting a moire fringes onto a tail fin, the deformed fringe pattern containing 3D information was produced and varied with the movement of tail fin. The time-sequence deformed fringe pattern images were captured by a high speed camera. By wavelet transform profilometry, the tail fin movements were really reconstructed. On this basis, the kinematics parameter of tail fin was analyses. Experimental results indicate that the 3D profile of tail fin was varied during the tail-beat cycle. Analysis of tail kinematics suggests that, at a swimming speed 0.5 Ls -1 , the tail beat frequency is 1.42 Hz and the dorsal lobe of the tail undergoes a 15.6% greater lateral excursion than does the ventral lobe. The timing of maximal lateral excursion was different at different location of tail fin.

A 3D Fourier transform for vibration measurement of an object based on shadow moire technique is presented. A sinusoidal grating is placed closed to a vibrating object. The moire fringe patterns generated by the interference of grating lines and shadow lines are captured by a high-speed camera. The joint spatial and temporal information of the fringe sequence is processed by use of the 3D Fourier transform simultaneously rather than separately, then a 3D space-time phase distribution can be obtained from the filtered spatiotemporal spectra. From the phase values, the surface profile, and displacement of the object at different time can be retrieved. The experiment for measurement of a vibrating cantilever beam is used to demonstrate the validity of the technique. The results show that shadow moire with spatiotemporal analysis can be applied to dynamic measurement.

Phase shifting technique is an effective approach to eliminate the zero order diffraction and the conjugate image in numerical reconstruction of digital holography. In this paper, the diffraction optical field of each component of a digital hologram is simulated solely and numerically by Fresnel diffractive integral. Based on this work two algorithms for two and three step phase shifting digital holography are proposed. The simulating results of two algorithms show that the proposed two phase shifting methods can not only recover the object wave front alone but also simplify the measurement process when compared with the usual four-step phase shifting method, because fewer phase shifting steps are needed accordingly. The proposed two algorithms may be a very useful reference for various kinds of measurement using the digital holography in practice.

Optical triangulation is a useful method that has been studied and utilized extensively. In optical triangulation, the directions of projection and the observation are different, so the patterns captured by CCD camera include information of the object surface profile. Based on the speckle projection, a measurement system to get the three-dimensional deformation of object is developed. With artificial random speckle projected to the object surface, two images before and after object deformation are recorded, respectively. In order to get the information of the deformation, digital image correlation method (DICM) is adopted. Furthermore, the calibration is introduced in detail, which is the procedure of great importance, because it determines directly the accuracy of measurement. Due to variable feature of the calibration coefficient along the x direction, this paper presents a new method to be competent for the calibration, that's segmented calibration method. Experiment is performed and good agreement is found with the proposed calibration. Dynamic measurement results based on such system are also presented in this paper.

The existence of zero-order image has certain effect on the quality of reconstructed images in off-axis digital holography. For eliminating the zero-order image in off-axis digital holography, a method of zero-order image elimination in off-axis digital holography by using of FIR (Finite Impulse Response) filter is proposed in this paper. This method is based on digital image processing. First, by analyzing the spatial spectrum characteristic of off-axis digital hologram and the principle of using FIR filter to eliminate zero-order image, the paper theoretically proved that the zero-order image can be effectively eliminated by the FIR filter method before reconstruction. Then, the digital simulation and experiment recorded holograms were processed in the program with the FIR filter method and reconstruction. Both the theoretical analysis and digital reconstruct results show that it can effectively eliminate the large bright spot in the center of the reconstructed image which caused by zero-order image, and improve the image quality significantly, give better contrast of the reconstructed image. This method is very simple and convenient for free of phase modulator or any extra optical element and needing only one time record.

Quasi-static axial compression and drop mass impact tests were performed to study the energy absorption behaviour of the closed-cell aluminium foam. Digital image analysis was firstly used to characterize the surface's structure of individual cells and aggregates of cells. The cell structure characterizations performed using the best-fit ellipse equivalent diameter for the individual cells, which included measurement of the size distribution of cells, cell's aspect ratio and orientation. It shows that the statistical distribution of cells' size and cell's aspect ratio well follow Gauss distributions. The energy absorption behavior of the high porosities aluminium foam under static and drop weight impact compression were then conducted. High-speed imaging technique and temporal digital image correlation method were employed to evaluate the deformation and acceleration in the compression experiments. Using these approaches, the deformation and energy absorption mechanism of Al foam due to drop impact can be observed and better understood. The experimental results show that aluminium foams are quite close to a kind of isotropic structure and have high energy absorption capabilities.

In order to learn the microstructure mechanics property of lime solidify soil, the digital image tracking technology has been introduced and used to track the soil particles, based on the micro-images captured by the long work distance telecentric microscope lens. On one hand, the sample of lime solidify soil is made into cylinder specimen. One of the half-parts is taken as the experimental specimen. Then, the region plane observed in the middle of soil specimen is compartmentalized nine small regions. One of the small regions is the tracking objective. When the objective is tracked successfully, the images of nine regions under the same loads are captured. On the other hand, using the transformed correlation formula, the tracking speed is improved. Moreover, According to the characteristic of soil under loads, the objective is successfully tracked by selecting the rectangle template and rectangle search region. Finally, using the image processing method, the evolution regulations of the porosity of soil sample under uniaxial stress are obtained. That is, the porosity is increased with the rising stress. In conclusion, the microstructure characteristic of lime solidify soil is agree with the macro property of lime solidify soil.

Tail fin is an important part of the fish to produce thrust in swimming. A three-dimensional (3D) analysis is necessary to understanding the function of tail fin. A precise test method for 3D tail fin profile is critical to study the tail fin kinematics. This paper describes the 3D shape measurement of swimming fish fin by a non-contact optical method based on the fringe projection technique. Sinusoidal fringes are projected onto fish during steady swimming by a slide projector. It will produce the deformed fringe patterns containing 3D information. These time-sequence deformed fringe pattern images are captured by a high speed camera (1000 frames per second). By 2D Fourier transform, filter, inverse Fourier transform and unwrap phases in 3D phase space frame-by-frame, the instantaneous 3D shape is obtained and the continuous variety profiles of tail fin are reconstructed. This paper displays parting the profiles in a quarter of a beat cycle, the steady swimming speed with 0.5Ls -1 (where the L is fish body length). The present study provides a new method to quantify the analysis of kinematic characteristic of the tail fin during steady swimming.

Recent advances in the electronics industries are drove by the rapid development of LCD technology. However, warpage is one of the major reliability and quality concerns in chip-on-glass (COG) packaging. Optical technique combined with microscopes is an obvious candidate for the non-contact measurement of warpage of LCD chips whose profiles vary from nanometers to micrometers. In this paper, projection speckle correlation method and Newton's ring interferometry are employed to obtain the warpage of a LCD chip. With respect to projection speckle correlation method, the technique of image merging is necessary in registration of 3D shape of entire object. Continuous wavelet transform is employed to extract 3D profile of the electronic chip by analyzing its fringe patterns. Phase retrieval is performed by computing the phase at a wavelet ridge. In addition, the points which introduce phase ambiguity are identified by tracking the inflexion points on the unwrapped phase map and detected by Savitzky-Golay differential operator. The feasibility of the proposed method is also validated by simulations. Experimental results from both techniques are compared, and excellent agreement is found. Above conclusions demonstrate that the techniques proposed in this study are powerful inspection tools for measuring warpage of LCD chips.

A new digital image method for measuring soil landslide displacement is presented in this paper. First, the principle of surface fitting method to determine the sub-pixel gray value is introduced. Second, the optical experimental system and the specimen used in this experiment are described in detail. Then, the soil micro-displacement field can be measured by obtaining the clear image sequence of soil micro-slide of an expansive soil sample under water load and searching the gray value in sub-pixels by digital image surface fitting technology. The results show that through the optical system, this nondestructive testing method can improve the measurement accuracy, and has a very good prospect of application in the study of soil landslide. After getting a great deal of useful data, the principal of the displacement in different times and in different locations under different water load can be obtained by drawing displacement curves, consequently the experimentation can provide useful data for disaster prevention and mitigation research and actual construction. In addition, if using a CCD with higher resolution and more effective record area, or using synthetic aperture technology to increase effective record area, the accuracy of the experiment are expected to be further enhanced.

In this paper, a simple speckle technique utilizing a charge-coupled device (CCD) camera and frequency and spatial domain combined correlation, is developed to measure 3D rigid-body displacement of an object. Rigid-body displacement in an arbitrary direction in space consists of both in- and out-of-plane components. On the basis of the pinhole perspective camera model, the presence of in-plane component of displacement results in a shift of the displacement vector center and constant slope of the displacement vector is related to the out-of-plane component. The proposed method facilitates the separation of in- and out-of-plane displacements. Based on the linear distribution features of the displacement vector, digital image correlation (DIC) in global coordinates is employed to locate the displaced position of each point on the object, which has been validated to be more accurate than conventional means. Correlation in frequency domain is combined with the technique in spatial domain to improve the speed and automation in the initial searching process. Simulation and experimental results demonstrate that both in-plane and out-of-plane displacements can be accurately measured with the proposed method.

A new two-step phase-shifting fringe projection profilometry is proposed. The slowly variable background intensity of fringe patterns is removed by the use of an intensity differential algorithm. The high-resolution differential algorithm is achieved based on global interpolation of fringe gray level on a subpixel scale. Compared with the traditional three- or four-step phase-shifting method, the profile measurement is sped up with this approach. Computer simulation and experimental performance are evaluated to demonstrate the validity of the proposed measurement method. The experimental results compared with those of the four-step phase-shifting method are presented.

We present a new approach for online incremental word acquisition and grammar learning by humanoid robots. Using no data set provided in advance, the proposed system grounds language in a physical context, as mediated by its perceptual capacities. It is carried out using show-and-tell procedures, interacting with its human partner. Moreover, this procedure is open-ended for new words and multiword utterances. These facilities are supported by a self-organizing incremental neural network, which can execute online unsupervised classification and topology learning. Embodied with a mental imagery, the system also learns by both top-down and bottom-up processes, which are the syntactic structures that are contained in utterances. Thereby, it performs simple grammar learning. Under such a multimodal scheme, the robot is able to describe online a given physical context (both static and dynamic) through natural language expressions. It can also perform actions through verbal interactions with its human partner.

Multiple steps in mRNA processing and transcription are coupled. Notably, the processing of mRNA 3′ ends is linked to transcription termination by RNA polymerase II. Previously, we found that the yeast hnRNP protein Npl3 can negatively regulate 3′ end mRNA formation and termination at the GAL1 gene. Here we show that overexpression of the Hrp1 or Rna14 subunits of the CF IA polyadenylation factor increases recognition of a weakened polyadenylation site. Genetic interactions of mutant alleles of NPL3 or HRP1 with RNA15 also indicate antagonism between these factors. Npl3 competes with Rna15 for binding to a polyadenylation precursor and inhibits cleavage and polyadenylation in vitro. These results suggest that an important function of hnRNP proteins is to ensure the fidelity of mRNA processing. Our results support a model in which balanced competition of Npl3 with mRNA processing factors may promote recognition of proper polyadenylation sites while suppressing cryptic sites.

To investigate the effects of upper limbs' encircling motion (ULEM) apparatus on motor function of patients with stroke.This study adopted a single-blind, prospective, randomized control design. From July 2003 to September 2005, 44 inpatients suffering from stroke in Jiangsu Province Hospital were enrolled in this study. All the subjects were randomized into two groups.Group A received ULEM therapy and conventional physical therapy (PT) aand group B received PT only. Blood pressure, pulse, Brunnstrom stage and Barthel Index were tested before and after 20 days' treatment.In group A, according to Brunnstrom stage, the effective rates of hand, upper extremities and lower extremities were 20.0%, 80.0% and 100.0%, respectively, and the total effective rate improved significantly compared to that of group B (p0.05), especially lower extremities (p0.05). There was no statistical difference in Barthel Indexes between two groups (p0.05).ULEM apparatus can significantly improve integrative motor function of extremities of patients with stroke. It is a safe and effective treatment.

A new technique for phase retrieval from non-monotonous fringes is presented. Continuous wavelet transform is employed to extract unwrapped phase. The ambiguity phase is identified by directly tracking an inflexion points on the unwrapped phase curve. Both simulations and experiments are conducted to validate the feasibility of the proposed method.

Digital image correlation method (DICM) is employed to measure the mechanical behavior of Precontraint 1202 Fluotop T2 membrane materials under biaxial loading conditions. In this study, shape functions in global coordinates are preferred, which is validated to determine large rigid body displacements as well as small strains more accurately. Creep tests are also carried out and the corresponding creep properties are analyzed. During the tests, images of the membrane surface are captured in real-time by a CCD camera. DICM is subsequently used to calculate strains by correlating the images recorded before and after deformations. Based on the results from DICM, modulus of elasticity, Poisson's ratio and creep curves are determined. Experimental results demonstrate the accuracy of the proposed method in evaluating the tension behavior of membrane materials, and prove the proposed method as a direct inspection tool and a practical alternative to the standard electrical measurements.

The structure deformation measurement is always to be the important problem of the field of the structure engineering. The traditional way of structure deformation measurement is not exact enough, and it is complex. While the optical measurement method has many good qualities such as high precision, simple facilities, changeable optical line, no damnification to the measured object, no special treatment to the surface of the measured object and so on. It has been abroad used in macroscopical fields and microcosmic fields, especially in wisp deformation measurement. Thus we tried measuring small structure deformation using the digital holography interferometry which is in the field of the optical measurement.

Iron overload (IO) is a kind of disease with an excess of iron depositing in the body's organs and tissues, resulting in the dysfunction of these organs and tissues, which contains hereditary hemochromatosis and secondary IO such as ineffective hematopoiesis in aplastic anemia and myelodysplastic syndrome (MDS) and blood transfusion. Numerous researches and our previous study found that IO can damage the hematopoietic function in bone marrow. MDS is one of the most common IO diseases and IO can further injure the hematopoietic function especially on erythropoiesis in MDS.However, it is indeterminacy on the mechanism behind this stiuation. This study is to explore the possible mechanism of IO on the injury of MDS erythropoiesis though establishing an IO MDS mice model. In this study, we first established an IO mice model by administering iron dextran(25 mg/ml) by intraperitoneal injection every 3 days for 2 months in wild and MDS mouse(NUP98-HOXD13 transgenic mouse). The mouse were devided into four grups: the wild mouse without IO(Ctrl group), the wild mouse with IO (IO group), MDS mouse without IO(MDS group), the MDS mouse with IO(MDS+IO group). After 6 months, the establishment of IO mice models were confirmed by both the iron deposits staining of bone marrow(BM), liver, spleen and the labile iron pool level of bone marrow mononuclear cells( BMMNCs). We next found that IO damage the erythropoiesis in MDS mice. We detected the proportion of different stages BM erythroblasts by flow cytometry plots of Ter119+ CD71+ cells (R1, basophilic erythroblasts, poly red cells, immature red blood cells) and Ter119+ CD71- cells (R2, late erythroblast and reticulocyte ). It was found that the hematopoietic colony-forming unit (CFU-E, BFU-E) in MDS+IO group were less than that in other groups. The proportion of R1(10.39±1.43) and R2(1.58±0.54) in MDS+IO group were the least compared with Ctrl group(R1 17.36±3.45,R2 4.59±1.57),IO group(R1 14.53±2.65,R2 2.56±0.76) and MDS group(R1 13.64±3.27,R2 2.35±0.78). And the reticulocytes proportion in MDS+IO group(11.36±3.65) was the highest compared with Ctrl group(5.159±1.537), IO group(7.61±1.36)) and MDS group(7.35±1.39). Then we further explored the mechanism of IO damage on MDS erythropoiesis. It was reported that TGF-β family and oxidative stress (ROS) played an important role on erythropoiesis. Our previous studies also had shown that the ROS and GDF11(a member of TGF-β family) levels were raised in BMMNCs on C57BL/6 mice with IO. Similarly, we detected them on the BM erythroblast in this study. Firstly, we sorted the R1 and R2 erythroblasts,then we performed RT-PCR to analyze mRNA levels of the TGF-β family. We found that the mRNA levels of GDF11, GDF15, Activin B, Acvr2b and ALK5 in MDS+IO group were the highest compared with that of other groups, while the mRNA levels of Activin A, ALK4 and BMP8 had no significant change in these groups. As we found that the change of GDF11 level was the most significant in MDS+IO group compared with other groups, we focused on the study of GDF11 in the following experiment. The concentration of GDF11 in peripheral serum was detected by ELISA method. It was found that the concentration of GDF11 was the highest in MDS+IO group compared with other groups. And also, the GDF11 related signal pathway proteins (Smad 2, Smad 3, p-Smad 2 and p-Smad 3) were significantly elevated in R1 and R2 erythroblast in MDS+IO group compared with other groups,which indicated that GDF11 related signal pathway was involved in the deficient of BM erythropoiesis in MDS+IO mice. Furthermore, We found that the ROS levels in Ter119+ cells in MDS+IO group, MDS group and IO group were increased 4.15 folds, 2.16 folds , 2.63 folds compared with Ctrl group. RT-PCR was used to detect the mRNA expression levels of the gene NOX4 related to ROS generation and GPX1 related with ROS clearance. It was found that the NOX4 expression levels were the highest in MDS+IO group compared with other groups,while the GPX1 mRNA level was the least in MDS+IO group. In conclusion, our study indicated that chronic IO damage the erythropoiesis in MDS mouse by increasing GDF11 and ROS levels which would provide an theoretical basis to find new targets for the treatment of IO in MDS patients with erythropoiesis dysfunction. Disclosures No relevant conflicts of interest to declare.

Background: Recent years, the incidence and mortality of fungal infection has been on the rise in the patients with hematologic malignancies. This is mainly associated with antifungal resistance and the restricted number of available antifungal drugs. Candida species is one of the most prevalent pathogens in these immunodeficient patients. However, the study of azole resistance mechanisms of Candida has focused on C.albicans, C.glabrata, C.tropicalis. And few studies talked about resistance mechanisms of C.krusei, especially resistant to itraconazole. It was reported that the mutation or overexpression of 14¦Á-demethylases (encoded by ERG11) and upregulation of efflux transporters (encoded by ABC1 and ABC2) may be involved in azole resistance of C.krusei. Here, The purpose of the present study is to preliminarily explore the main molecular mechanisms responsible for Candida krusei clinical isolates to itraconazole, and may provide new sight into fungal infection therapy. Methods: The 14¦Á-demethylases encoded by ERG11 gene in the 16 C.krusei clinical isolates were amplified by polymerase chain reaction (PCR), and their nucleotide sequences were determined to detect point mutations. Meanwhile, ERG11 and efflux transporters (ABC1 and ABC2) genes were determined by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) for their expression in itraconazole-resistant (R), itraconazole-susceptible dose dependent (SDD) and itraconazole- susceptible (S) C.krusei at the mRNA level. Results: We found 7-point mutations in ERG11 gene of all the C.krusei clinical isolates, including 6 synonymous mutations and 1 missense mutation (C44T). However, the missense mutation was found in the three groups. The mRNA levels of ERG11 gene in itraconazole-resistant isolates showed higher expression compared with itraconazole-susceptible dose dependent and itraconazole- susceptible ones (P=0.015 and P=0.002 respectively). ABC2 gene mRNA levels in itraconazole-resistant group was significantly higher than the other two groups, and the levels of their expression in the isolates appeared to increase with the decrease of susceptibility to itraconazole (P=0.007 in SDD compared with S, P=0.016 in SDD with R, and P Conclusions: There are ERG11 gene polymorphisms in clinical isolates of C.krusei. ERG11 gene mutations were not found to be involved in the development of itraconazole resistance in C.krusei. ERG11 and ABC2 overexpression might be responsible for the acquired itraconazole resistance of these clinical isolates. Therefore, combination of azole and selective efflux transporter inhibitors may help reverse azole resistance and enhance antifungal effect. Figure 1. ABC2 relative gene expression levels in three groups of C.krusei clinical isolates. (A) Relative levels of ABC2 mRNA in all the C.krusei clinical isolates. ABC2 gene expression levels was quantified and normalized relative to the housekeeping gene, ACT1; S, itraconazole-susceptible; SDD, itraconazole-susceptibledose dependent; R, itraconazole-resistant. (B) Log10+3 fold increase of gene expression levels in three groups. (*P Disclosures No relevant conflicts of interest to declare.

A simple and repeatable speckle creation method based on water transfer printing (WTP) is proposed to reduce artificial measurement error for digital image correlation (DIC). This technique requires water, brush, and a piece of transfer paper that is made of prefabricated decal paper, a protected sheet, and printed speckle patterns. The speckle patterns are generated and optimized via computer simulations, and then printed on the decal paper. During the experiments, operators can moisten the basement with water and the brush, so that digital patterns can be simply transferred to the carriers' surfaces. Tensile experiments with an extended three-dimensional (3D) DIC system are performed to test and verify the validity of WTP patterns. It is shown that by comparing with a strain gage, the strain error is less than 50μe in a uniform tensile test. From five carbon steel tensile experiments, Luders bands in both WTP patterns and spray paint patterns are demonstrated to propagate symmetrically. In the necking part where the strain is up to 66%, WTP patterns are proved to adhere to the specimens well. Hence, WTP patterns are capable of maintaining coherence and adherence to the specimen surface. The transfer paper, working as the role of strain gage in the electrometric method, will contribute to speckle creation.

In plant pararetroviruses, pregenomic RNA serves both as a template for replication through reverse transcription and a polysictronic mRNA. This RNA has a complex leader sequence preceding the first large ORF. The leader contains multiple short ORFs and strong secondary structure, both inhibiting ribosome scanning. Translation on this RNA is initiated by shunting, in which scanning ribosomes bypass a large portion of the leader with the inhibitory secondary structure and short ORFs. In Cauliflower mosaic virus (CaMV), the ribosome shunting mechanism involves translation of the 5′-proximal short ORF terminating in front of the secondary structure that appears to force ribosomes to take off and resume scanning at a landing site downstream of the structure. Using two plant protoplast systems and shunt-competent wheat-germ extracts, we demonstrate that in Rice tungro bacilliform virus (RTBV) shunting also depends on the first short ORF followed by strong secondary structure. Swapping of the conserved shunt elements between CaMV and RTBV revealed the importance of nucleotide composition of the landing sequence for efficient shunting. The results suggest that the mechanism of ribosome shunting is evolutionary conserved in plant pararetroviruses.

This paper presents a new method that acquires the height information automatically in projected fringe patterns for 3D profile. The principle is to project the gratings on reference plane and object surface to be measured respectively, and then record them by a CCD camera. Through comparing these two images with digital image correlation method, the offset of the fringe that modulated by the object surface can be obtained. Further the 3D profile or deformation will be inferred. In this new method, an important characteristic is that the principle and processing are only need one fringe pattern on object surface, so it can be well used in real time and dynamic measurement. Another advantage is no need of the complex unwrapping process. At last, this paper shows the experiment results and compared them with phase shifting method.

It is well known that the introduction of a phase-shifting procedure may give a better resolution in optical techniques. This paper presents a new digital shadow moire method with phase-shifting based on liquid crystal display (LCD) projector. The first one of four computer-generated phase-shifting fringe patterns is projected on the surface of testing object while all fringe patterns are sequentially projected on a planar plate for generating phase-shifting moire fringes, which are formed by the projected phase-shifting fringe patterns subtracting with the deformed fringe pattern in sequence. This new method provides many advantages in performing topography and out-of-plane displacement measurement. First, the spatial line period and phase step is readily adjusted to suit the measurement precision. Second, the measuring speed is relatively fast and suit for dynamic testing because the digital phase shifting is no time-consuming comparing with other phase-shifting techniques. The experimental performance on out-of-plane displacement measurement of a cantilever beam well demonstrates the validity of the new method.

A 60-nucleotide region (S1) downstream of the transcription start site of the cauliflower mosaic virus 35S RNA can enhance gene expression. By using transient expression assays with plant protoplasts, this activity was shown to be at least partially due to the effect of transcriptional enhancers within this region. We identify sequence motifs with enhancer function, which are normally masked by the powerful upstream enhancers of the 35S promoter. A repeated CT-rich motif is involved both in enhancer function and in interaction with plant nuclear proteins. The S1 region can also enhance expression from heterologous promoters.

The maturation of mRNA occurs cotranscriptionally in vivo and is facilitated by the recruitment of mRNA processing factors to the phosphorylated C-terminal domain (CTD) of the largest subunit of RNA polymerase II (RNAP II) (for a review, see reference 40). During transcription, the nascent pre-mRNA is capped at the 5′ end, introns are removed by splicing, and the 3′ end is cleaved and polyadenylated. The processing of the 3′ end promotes transcription termination and nuclear export, and acquisition of a poly(A) tail is essential for the production of functional mRNA. The cleavage and polyadenylation steps take place within a large complex of proteins that for the most part are highly conserved between yeast and mammals (13). In the yeast Saccharomyces cerevisiae, CF IA, Hrp1/Nab4, and CF II are sufficient for the cleavage reaction in vitro, while specific poly(A) addition requires CF IA, Hrp1, poly(A) binding protein, and the CPF complex, which is composed of CF II, poly(A) polymerase, and additional proteins. A subset of these components are important in causing RNAP II to terminate downstream of poly(A) sites or of genes encoding some snRNAs and snoRNAs (2, 5, 11, 33). Recent application of a tandem affinity purification strategy allowed several groups to isolate highly purified CPF from yeast whole-cell extract (10, 16, 21, 36). This complex contains the nine previously characterized CPF subunits (references 39 and 62 and references therein), several novel polypeptides (including Glc7, Pti1, Ssu72, and Swd2) with no previous links to the cleavage and polyadenylation machinery, and Ref2, an RNA-binding protein known to stimulate processing at weak poly(A) sites (46). Nedea et al. (36) proposed that these new proteins form a subcomplex of CPF called APT (for associated with Pta1) that is connected to core CPF by Pta1. Two of these APT subunits, Pti1 and Ref2, have minor roles in mRNA processing but are very important for maturation of snoRNA 3′ ends (9, 36, 46, 52) which are cleaved but not polyadenylated. Ssu72, a low-molecular-weight phosphatase (15, 30), is essential for 3′ end formation of both types of RNAP II transcripts (21, 36, 57) and also contributes to accurate initiation of RNAP II transcription (60). Glc7, the only type 1 serine/threonine protein phosphatase in S. cerevisiae, has been implicated in numerous nuclear and cytoplasmic processes, including transcription regulation and mRNA export (17, 56). The fourth APT subunit, Swd2, is a 37-kDa protein without a proven cellular function. It has six WD repeats, which are domains of about 40 amino acids that usually end with tryptophan-aspartic acid (WD). WD repeat proteins are thought to have circularized β-propeller-like structures, which can interact sequentially or simultaneously with several different proteins (53). The presence of Swd2 in the CPF complex suggests that it may be directly involved in mRNA or snoRNA 3′ end formation or may help coordinate 3′ end processing with other events in mRNA synthesis and utilization. Swd2 is also part of the Set1, or COMPASS, complex, which is composed of Set1, Bre2, Swd1, Swd2, Swd3, Spp1, Shg1, and Sdc1 (31, 34, 44). This complex, through its catalytic subunit Set1, adds one to three methyl groups specifically to lysine 4 of histone H3 (H3-K4) (6, 31, 34, 44). This function is required for position-dependent gene silencing at telomeres, the mating type locus, and ribosomal DNA (6, 8, 25, 38). Set1-mediated H3-K4 dimethylation in S. cerevisiae is found throughout the genome, while the trimethylated form is most prevalent in the coding regions of active or recently transcribed genes (3, 37, 48; reviewed in references 20 and 51) and may protect active coding regions from deacetylation (3). The purpose of the work described in this report is to examine the role of Swd2 in the processes of histone methylation, transcription, and mRNA 3′ end formation. Here we demonstrate that Swd2, as a bona fide member of the Set1 complex, is required for global histone H3-K4 methylation and other Set1-regulated events. In spite of its tight association with the CPF complex, Swd2 is not directly involved in pre-mRNA 3′ end processing. However, we show that Swd2 plays a role in RNAP II transcription termination that is not dependent on its function in histone methylation. We propose that Swd2, as part of CPF, helps to coordinate the activities of the transcription and 3′ end processing machineries.

A new phase unwrapping algorithm is proposed in this paper. This algorithm, based on the global continuity of the physical information being measured, is shown to be reliable by experimental results. Unlike the brunch-cut method, this new algorithm needs not placing brunch cuts but ratifying the errors in the initial unwrapped phase map obtained by the conventional method using the least difference of phase-cross-section. It is suitable for unwrapping phase map in the presence of errors such as noise, phase discontinuity more than (pi) and insufficient sampling. In addition, the new method is simple and requires little computing time.

The reliability and lifetime of microelectromechanical systems (MEMS) are strongly depending on the material properties. It is important to develop methods for the measurement of MEMS material properties. In this paper an optical technique for measuring tensile strain of micro-specimen is proposed. The technique, which is based on digital speckle correlation method works by determining the deformation of specimen between two neighboring loading step by step. The problem of non-correlation is solved when the deformation is too large. The experimental results of a copper wire are given in this paper. The proposed technique is also applicable for measuring other MEMS materials that may be even smaller or thinner than that used in this paper.

In this paper, optical methods for the surface profile and deformation measurement of MEMS materials and structures are introduced. The methods are based on the digital image correlation, interferometry and fringe projection. The deformations of a micro-mirror and a micro-beam are measured by phase shifting fringe projection and interferometry. The surface profile of an electrode pad was used for the demonstration of the microscopic surface contouring. For the MEMS material test, using a long working distance microscope and digital speckle correlation method the tensile strain of a thin copper wire is measured.

Downstream sequences influence activity of the rice tungro bacilliform virus (RTBV) promoter in protoplasts derived from cultured rice cells. We previously identified a DNA element located between positions +50 and +90 relative to the transcription start site to which rice nuclear proteins bind. In this study, using DNA UV crosslinking assays, we show that two rice nuclear proteins bind specifically to this DNA element. We demonstrate that the DNA element enhances RTBV promoter activity in a copy number-dependent manner when transferred to a position upstream of the promoter. In addition, using electrophoretic mobility shift assays, we show that at least two novel nuclear proteins from rice cell suspension cultures bind to a subregion (from +50 to +59) of the DNA element and that a protein from rice root, but not shoot, nuclear extracts interacts with a perfect palindromic sequence motif located within the sequence +45 to +59. Furthermore, a position-dependent GAGA motif, present in three copies within downstream promoter sequences from +1 to +50, is involved in the regulation of RTBV promoter activity.

The PhoP-PhoR two-component system plays a key role in regulating virulence of Mycobacterium tuberculosis. The response regulator PhoP is a transcription regulator, and it regulates expression of more than 100 genes. PhoP belongs to the OmpR/PhoB subfamily of response regulators. Despite extensive research in recent years, the molecular mechanism of DNA sequence recognition by this large subfamily of response regulators is not fully understood, especially the role of the N-terminal regulatory domain on DNA binding of the effector domain. Here we present a crystal structure of the full-length PhoP in complex with a direct-repeat DNA sequence. PhoP binds to DNA as a dimer. The two effector domains bind in tandem, each interacting with a half site of the direct repeat DNA. The DNA recognition helix inserts into the major groove, reading the sequence of a 7-bp motif. The wing residues interact with the downstream sequence, with a conserved arginine side chain inserting into the minor groove. Surprisingly, the regulatory domain also forms a tandem arrangement, instead of the anticipated symmetric dimer. The regulatory domain of the upstream protomer interacts with both domains of the downstream protomer. The structural elements of the alpha4-beta5-alpha5 face, which often found to be involved in dimer interface of the regulatory domain, play important roles in the interactions between the protomers. The crystal structure explains why PhoP recognizes direct repeats of two 7-bp motifs with a strict spacing of 4 bp and the highly cooperative binding of the two monomers. Detailed analysis of the structure along with analysis of the DNA sequence requirements and ITC measurements of protein-DNA binding interactions will be presented.

The mechanical reliability of electronic packaging is a topic of concern. Characterization of the thermo-mechanical behavior including the thermal stress/strain of electronic packages is critical for this topic. In this paper, current principal experimental methods used for this purpose are reviewed, their advantages and disadvantages are analyzed, also their newest applications are introduced. The hybrid method that takes the advantage of experimental methods and finite elemental method -- FEM is pointed out to be the best investigation method and represents a developing direction.

This paper describes the use of optical fringe projection method for 3D surface profile measurement of object. In this method, sinusoidal linear fringes are projected on the object surface by a programmable liquid crystal display projector. The image of the fringe patter in captured by a CCD camera and processed by phase-shifting techniques. A simple procedure is described which enables calibration of the optical set-up for subsequent quantitative measurement of unknown object shapes. This method is relatively simple and accurate, and is capable of conducting fully automated measurements.

This paper describes an optical system for high temperature strain measurement by using quartz optical fiber, super long working distance microscope and digital image processing techniques. In this system one ends of the quartz optical fibers are arrayed in a small area on the specimen surface and the other ends are illuminated by a laser beam. The fiber ends on the specimen surface from the spot array. The small optical spots on the specimen are tracked by a CCD camera and the images are processed by digital image processing software. As the diameter of each quartz fiber is only 100 microns the fibers can be arrayed in a tiny area. The local strains were determined by measuring the variety of relative distance between two spots. The measurement results of local creep strain on the welding joints of 15CrMo and HK40 at 850 degrees C are obtained.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Nuclear proteins from rice (Oryza sativa) were identified that bind specifically to a rice tungro bacilliform virus promoter region containing a vascular bundle expression element (VBE). One set of proteins of 29, 33, and 37 kDa, present in shoot and cell suspension extracts but hardly detectable in root extracts, bound to a site containing the sequence AGAAGGACCAGA within the VBE, which also contains two CpG and one CpNpG potential methylation motifs. Binding by these proteins was determined to be cytosine methylation-independent. However, a novel protein present in all analyzed extracts bound specifically to the methylated VBE. A region of at least 49 nucleotides overlapping the VBE and complete cytosine methylation of the three Cp(Np)G motifs was required for efficient binding of this methylated VBE-binding protein (MVBP).

To investigate the transcriptional mechanisms of rice tungro bacilliform virus, we have systematically analyzed an activator element located immediately upstream of the TATA box in the rice tungro bacilliform virus promoter and its cognate trans-acting factors. Using electrophoretic mobility shift assays, we showed that rice nuclear proteins bind to the activator element, forming multiple specific DNA-protein complexes via protein-protein interactions. Copper-phenanthroline footprinting and DNA methylation interference analysis indicated that multiple DNA-protein complexes share a common binding site located between positions -60 to -39, and the proteins contact the activator element in the major groove. DNA UV cross-linking assays further showed that two nuclear proteins (36 and 33 kDa), found in rice cell suspension and shoot nuclear extracts, and one (27 kDa), present in root nuclear extracts, bind to this activator element. In protoplasts derived from a rice (Oryza sativa) suspension culture, the activator element is a prerequisite for promoter activity and its function is critically dependent on its position relative to the TATA box. Thus, transcriptional activation may function via interactions with the basal transcriptional machinery, and we propose that this activation is mediated by protein-protein interactions in a position-dependent mechanism.

The chip scale package (CSP) and flip-chip (FC) technologies are currently developed by electronic industry for high performance, high density and miniaturized assembly applications. The reliability of these packages continues to be a major concern due to the increase of die size, circuit density, and operating temperature. Moiré interferometry is a full field optical method, which can be used for the thermal mechanical deformation measurement of electronic packages and packaging materials. By using ordinary moiré interferometry, fringes represent displacement contour of 417 nm. In most cases, in a solder bump of CSP and FC packages, the thermal mechanical deformation is usually only 2 or 3 fringes (with relative displacement of about 1.2 μm), but the local strain of the bump is high because of the small size of the bump. It is difficult to resolve the local strain value for ordinary moiré interferometry, which can only resolve strain values averaged over a relative larger area. Based on high magnification and phase shifting method, refined micro moiré interferometer is expected to have a localized sensitivity and resolution for localized strain measurements. By using high precision close-loop controller for phase shifting in the refined moiré system, excellent results were obtained in the thermal mechanical deformation study of CSP samples and in the study of the solder bump mis-registration effect of FC samples. The results also showed that refined micro moiré method is effective in resolving deformation within a small area like a corner of a C4 bump.

A window based graphics interface for phase shifting in a moiré interferometry system is introduced in this paper. VISUAL C++ is used in the software programming. The phase shifting is accomplished by driving the reference grating in the moiré interfermetry system with a low voltage piezo stack. Four images from three shifts and one original image are used to derive the phase diagram, which is used for displacement and strain calculations. Automatic fringe numbering is achieved by the phase shifting, which significantly simplifies the traditional fringe-counting process. The strain calculation is also automatic by space derivative of displacement. The displacement distribution is obtained by unwrapping the phase diagram. Various help menu functions are provided, facilitating the ease use of the software. A 3-point bending beam is used for the demonstration. The technique is also applied to the analysis of thermal deformations in a flip-chip electronic package.

Although it is challenging to resolve deformation fields near corners or interfaces for layered structures, it is essential for a measurement technique to deal with of stress/strain concentrations, strain gradients, failure initiation and growth, local microstructure evolutions, etc. In this study, an innovative phase shifting technique is proposed, coupled with an image processing software, to investigate several interesting problems in electronic packaging. A power plastic IC package and a flip-chip package are selected to demonstrate the powerfulness of the system. A nanoscale deformation field is obtained for both the corner area and the underfilled containing flip-chip solder balls.