Large Screen Projection Research Articles

大屏幕投影显示光学系统的超薄化设计

A novel ultra-thin refract-reflect projection display system was designed to meet the severe requirements of imaging lens in large screen projection display for ultra-short focal length, larger field of view, ultra-thin, larger relative aperture and higher resolution. A 0.65 inch (16.51 cm) Digital Micromirror Device (DMD) produced by TI Inc. was employed as the spatial light modulator and an aspheric mirror was used to correct distortion and shorten projection distance. Furthermore, a fold mirror was also taken to turn back the optical path to achieve ultra-thin projection display. The system is consisted of five lenses and an aspheric mirror, of which the focal length is 2.8 mm, the F-number is 3.5 and the minimum and the maximum field angles are 55 and 78.5, respectively. When the projection distance is set to be 120 mm, the screen size can be 65.2 inch (165.6 cm). With the design, it shows that the Modulation Transfer Function (MTF) of over 95% field of view of the system is higher than 0.6 at the Nyquist frequency of the image plane. The maximum distortion is 0.8TV%, and 90% geometric encircled energy in the point target is focused in one pixel. To verify the performance of the ultra-thin refract-reflect projecting lens, a principle prototype was fabricated and assembled. The experimental results show that the system has excellent display performance, and meets the design requirements of ultra-thin, low cost and small-scale mass production.

MNS16A tandem repeats minisatellite of human telomerase gene: a risk factor for colorectal cancer

Telomerase reactivation and expression of human telomerase gene [human telomerase reverse transcriptase (hTERT)] are hallmarks of unlimited proliferation potential of cancer cells. A polymorphic tandem repeats minisatellite of hTERT gene, termed MNS16A was reported to influence hTERT expression. To assess the role of MNS16A as potential biomarker for colorectal cancer (CRC), we investigated for the first time the association of MNS16A genotypes with risk of colorectal polyps and CRC. In the ongoing colorectal cancer study of Austria (CORSA), 3842 Caucasian participants were recruited within a large screening project in the province Burgenland including 90 CRC cases, 308 high-risk polyps, 1022 low-risk polyps and 1822 polyp free controls verified by colonoscopy. MNS16A genotypes were determined by polymerase chain reaction from genomic DNA. Associations of MNS16A genotypes with CRC risk were estimated by logistic regression analysis computing odds ratios (ORs) and 95% confidence intervals (CIs). We identified five different variable number of tandem repeats (VNTRs) of MNS16A including VNTR-364, a newly discovered rare variant. VNTR-274 allele was associated with a 2.7-fold significantly increased risk of CRC compared with the VNTR-302 wild-type (OR = 2.69; 95% CI = 1.11-6.50; P = 0.028). In our CORSA study, the medium length VNTR-274 was identified as risk factor for CRC. Although, this population-based study herewith reports the largest cohort size concerning MNS16A thus far, further large-scale studies in diverse populations are warranted to confirm hTERT MNS16A genotype as potential biomarker for assessment of CRC risk.

Viewing medium affects arm motor performance in 3D virtual environments

Background2D and 3D virtual reality platforms are used for designing individualized training environments for post-stroke rehabilitation. Virtual environments (VEs) are viewed using media like head mounted displays (HMDs) and large screen projection systems (SPS) which can influence the quality of perception of the environment. We estimated if there were differences in arm pointing kinematics when subjects with and without stroke viewed a 3D VE through two different media: HMD and SPS.MethodsTwo groups of subjects participated (healthy control, n = 10, aged 53.6 ± 17.2 yrs; stroke, n = 20, 66.2 ± 11.3 yrs). Arm motor impairment and spasticity were assessed in the stroke group which was divided into mild (n = 10) and moderate-to-severe (n = 10) sub-groups based on Fugl-Meyer Scores. Subjects pointed (8 times each) to 6 randomly presented targets located at two heights in the ipsilateral, middle and contralateral arm workspaces. Movements were repeated in the same VE viewed using HMD (Kaiser XL50) and SPS. Movement kinematics were recorded using an Optotrak system (Certus, 6 markers, 100 Hz). Upper limb motor performance (precision, velocity, trajectory straightness) and movement pattern (elbow, shoulder ranges and trunk displacement) outcomes were analyzed using repeated measures ANOVAs.ResultsFor all groups, there were no differences in endpoint trajectory straightness, shoulder flexion and shoulder horizontal adduction ranges and sagittal trunk displacement between the two media. All subjects, however, made larger errors in the vertical direction using HMD compared to SPS. Healthy subjects also made larger errors in the sagittal direction, slower movements overall and used less range of elbow extension for the lower central target using HMD compared to SPS. The mild and moderate-to-severe sub-groups made larger RMS errors with HMD. The only advantage of using the HMD was that movements were 22% faster in the moderate-to-severe stroke sub-group compared to the SPS.ConclusionsDespite the similarity in majority of the movement kinematics, differences in movement speed and larger errors were observed for movements using the HMD. Use of the SPS may be a more comfortable and effective option to view VEs for upper limb rehabilitation post-stroke. This has implications for the use of VR applications to enhance upper limb recovery.

Association of IGF1 and IGFBP3 polymorphisms with colorectal polyps and colorectal cancer risk

Insulin-like growth factor 1 (IGF1) is a peptide growth factor that promotes cell proliferation and inhibits apoptosis. The bioavailability of IGF1 is regulated by the insulin-like growth factor binding protein 3 (IGFBP3). The purpose of this study was to examine the association of genetic variants in IGF1 (rs6214, rs6220, and rs35767) and IGFBP3 (rs2854744 and rs2854746) with risk of colorectal polyps and colorectal cancer. In this ongoing colorectal cancer study of Austria (CORSA), a total of 3,360 Caucasian participants, consisting of 178 colorectal cancer patients, 328 patients with high risk polyps, 1,059 patients with low risk colorectal polyps, and 1,795 colonoscopy-negative controls, were recruited within a large colorectal screening project in the province Burgenland and from three hospitals in Vienna. Multiple logistic regression was applied to compare individuals of the control group against three different risk groups, namely, colorectal cancer group, high risk polyp group, and low risk polyp group. Carriers of the homozygous polymorphic genotype of the SNP rs6214 were associated with an increased colorectal risk (OR = 1.79, 95% CI 1.04-1.90) compared to the colonoscopy-negative controls; this was also found when combining colorectal cancer cases and high risk polyp group (OR = 1.39, 95% CI 1.01-1.90). Our results suggest that the SNP rs6214 of IGF1 could have an impact on developing colorectal cancer and colorectal polyps with villous elements.

Screening Asymptomatic Adolescent Men for Chlamydia trachomatis in School-Based Health Centers Using Urine-Based Nucleic Acid Amplification Tests

Urine-based screening for Chlamydia trachomatis using highly sensitive and specific nucleic acid amplification tests offers a unique opportunity to screen men attending school-based health centers. As part of a large multicenter chlamydia screening project in men, 1434 students were enrolled; 1090 in high schools in Baltimore and 344 middle and high-school students in Denver. Students were screened for chlamydia using urine-based nucleic acid amplification tests at well adolescent visits, acute care visits, or visits for other reasons, such as sports physicals. A self-administered survey to ascertain sexual risk behaviors was used. Data were analyzed separately for Baltimore and Denver, with univariate and multivariate logistic regression analysis. The overall prevalence in asymptomatic adolescent men was 6.8% (7.5% in Baltimore and 4.7% in Denver, P = n.s.). Students in Denver were older, more racially diverse, and more likely to have had intercourse in the previous 2 months than students in Baltimore. Students in Baltimore were more likely than those in Denver to have used a condom at last intercourse with casual and main partners. Among men in Denver but not Baltimore, condom use at last intercourse with both casual (OR 0.15, 95% CI, 0.03, 0.78) and main partners (OR 0.30, 95% CI, 0.10, 0.91) was protective against infection. The only risk factor for CT infection in Baltimore students was age (OR 1.47, 95% CI, 1.23, 1.75). In multivariate analysis that included age (as a continuous variable), race, history of an STI, any sex partner in the last 2 months, >1 sex partner in the past 12 months, a new partner in the last 2 months, and condom use with last main and last casual partner, age (adjusted odds ratio 1.34, 95% CI, 1.11, 1.62) and black race (adjusted odds ratio 2.37, 95% CI, 1.21, 4.63) were the only variables associated with testing chlamydia positive. School-based health centers are important venues in which to perform urine-based screening for chlamydia in sexually active, asymptomatic males, especially in high prevalence communities, and such screening provides the opportunity to identify and treat substantial numbers of chlamydia infections.

An optimized procedure for the design and evaluation of Ecotilling assays

BackgroundSingle nucleotide polymorphisms (SNPs) are the most common form of genetic variability in the human genome and play a prominent role in the heritability of phenotypes. Especially rare alleles with frequencies less than 5% may exhibit a particularly strong influence on the development of complex diseases. The detection of rare alleles by standard DNA sequencing is time-consuming and cost-intensive. Here we discuss an alternative approach for a high throughput detection of rare mutations in large population samples using Ecotilling embedded in a collection of bioinformatic analysis tools. Ecotilling originally was introduced as TILLING for the screening for rare chemically induced mutations in plants and later adopted for human samples, showing an outstanding suitability for the detection of rare alleles in humans. An actual problem in the use of Ecotilling for large mutation screening projects in humans without bioinformatic support is represented by the lack of solutions to quickly yet comprehensively evaluate each newly found variation and place it into the correct genomic context.ResultsWe present an optimized strategy for the design, evaluation and interpretation of Ecotilling results by integrating several mostly freely available bioinformatic tools. A major focus of our investigations was the evaluation and meaningful economical combination of these software tools for the inference of different possible regulatory functions for each newly detected mutation.ConclusionOur streamlined procedure significantly facilitates the experimental design and evaluation of Ecotilling assays and strongly improves the decision process on prioritizing the newly found SNPs for further downstream analysis.

It's Turtles all the Way Down: A Comparative Analysis of Visually Induced Motion Sickness

One of the most frustrating aspects of motion sickness is the apparent lack of predictability, particularly from one context (seasickness) to another (cybersickness). It has been postulated that this lack of predictability is indicative of separate but related disorders. Recent evidence has suggested that the problem may not lie in the disorder itself, but in the measures used to predict it. Based on the predictions of Riccio and Stoffregen (1991) and the findings of Smart, Stoffregen, and Bardy (2002), a secondary analysis was performed using parameters of postural motion in order to classify participants who would later become motion sick across three laboratory (four modes of presentation: moving room (Smart, et al, 2002), high fidelity flight simulator (Stoffregen, et al, 2000) large screen projection, and head mounted display (Otten, 2005)) settings. Results suggest that measures of postural instability may serve as a common, minimally invasive, and predictive index of visually induced motion sickness.

Antimicrobial Properties of Substituted Salicylaldehydes and Related Compounds

A systematic survey of the antimicrobial properties of substituted salicylaldehydes and some related aromatic aldehydes is reported. A total of 23 different compounds, each at four different concentrations, were studied using a panel of seven microbes (Aspergillus niger, Bacillus cereus, Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Saccharomyces cerevisiae and Staphylococcus epidermidis) and employing the paper disc agar diffusion method. Several aldehydes, most notably halogenated, nitro-substituted and hydroxylated salicylaldehydes, displayed highly potent activity against the microbes studied, giving inhibitory zones up to 49 mm in diameter (paper disc diameter 6 mm), while unsubstituted benzaldehyde and salicylaldehyde had minimal activity. Further, 4,6-dimethoxysalicylaldehyde had considerable activity against C albicans and slight activity against S. cerevisiae, while displaying minimal activity against bacteria. Also two aromatic dialdehydes had interesting activity. In general, P. aeruginosa was the least sensitive microbe, a result that is in line with observations from a large screening project, in which this microbe was the one against which the least number of active substances was found. Interestingly, the structure-activity relationships of the aldehydes studied were clearly different for different microbes. Many of the aldehydes tested had such high antimicrobial activity that they are noteworthy candidates for practical applications as well as interesting lead compounds for the development of novel antimicrobial drugs and disinfectants. The structure-activity relationships are discussed in detail. For high activity, substituents are required in benzaldehyde as well as in its 2-hydroxy derivative salicylaldehyde. One hydroxy group alone (at the 2-position) is not enough, but further hydroxylation may produce high activity. The effects of substituents are in some cases dramatic. Halogenation, hydroxylation and nitro substitution may produce highly active compounds, but the effects are not easily predicted nor can they be extrapolated from one microbe to another.

Automated Yeast Two-hybrid Screening for Nuclear Receptor-interacting Proteins

High throughput analysis of protein-protein interactions is an important sector of hypothesis-generating research. Using an improved and automated version of the yeast two-hybrid system, we completed a large interaction screening project with a focus on nuclear receptors and their cofactors. A total of 425 independent yeast two-hybrid cDNA library screens resulted in 6425 potential interacting protein fragments involved in 1613 different interaction pairs. We show that simple statistical parameters can be used to narrow down the data set to a high confidence set of 377 interaction pairs where validated interactions are enriched to 61% of all pairs. Within the high confidence set, there are 64 novel proteins potentially binding to nuclear receptors or their cofactors. We discuss several examples of high interest, and we expect that communication of this huge data set will help to complement our knowledge of the protein interaction repertoire of this family of transcription factors and instigate the characterization of the various novel candidate interactors.

Evaluation of asthma control in subjects participating in a large multi-disease screening project

Evaluation of asthma control in subjects participating in a large multi-disease screening project

5 inch MgAl 2 O 4 phosphor screen for projection display

A new kind of MgA12O4 phosphor screen for projection display is reported. The 5 inch phosphor screen is fabricated by depositing powder on MgAl2O4 substrate. Because MgAl2O4 has the characteristics of higher heat conductivity than the conventional glass faceplate, the phosphor screen achieves very high brightness, good contrast ratio, high resolution and long lifetime, and therefore realises large-screen projection display.

Measurement of Highly Aspherical Surface using Computer Generated Holograms

Interferometric metrology with a null CGH(computer-generated hologram) is presented for measuring highly aspheric surfaces used in a large screen projection television system with high accuracy. The cubic spline surface model which works in a single-pass configuration with a refractive index of object space 0 is used for designing a null CGH. A hybrid null corrector with plano-concave lens in front of a CGH is presented to make the CGH easier to fabricate. Experimental results are presented to demonstrate the validity of the proposed technique.

Effectiveness of orbital shaking for the aeration of suspended bacterial cultures in square-deepwell microtiter plates

Growth of heterogeneous culture collections in microtiter plates is advantageous for logistic reasons and also in enabling significant savings in medium costs, labor input and use of equipment during large screening projects. The main hurdles to overcome for aerobic microbial strains are the prevention of cross-contamination and excessive evaporation while assuring sufficient aeration rates. For this purpose we developed a sandwich spongy silicone/cotton wool cover to close the wells of square-deepwell microtiter plates. Oxygen transfer rates were derived from growth curves of Pseudomonas putida and were shown to be threefold higher during orbital shaking at a shaking diameter of 5 cm at 300 rpm (24 mmol O 2 l −1 h −1 at a culture volume of 0.75 ml) in comparison to a shaking diameter of 2.5 cm. Photographic analysis showed a clear influence of the shaking diameter on the hydrodynamic behavior in the wells; during shaking at a 2.5 cm amplitude, out-of-phase conditions occurred resulting in poor vertical mixing, while a 5 cm shaking amplitude led to an optimal surface to volume ratio and a turbulent flow.

Virtual process week in the experimental vehicle build at BMW AG

For many years CA technologies have been used in different areas of product development. Now visualisation systems are able to support the assembly planning process. During a so-called “virtual process week” at BMW the current state of the assembly planning is estimated by a group of people responsible for the process. Based on the product structure visualisation scenes are created. By using the group function of the visualisation system parts are shown subsequently according to the assembly plan. The participants use eight criteria to assess the operation. All results are documented online in a database. To assure a good view to all people a large screen projection and two projectors are used in parallel in a daylight environment. Due to the amount of CAD data several workstations have to be used and connected individually to the projectors. In the end, statistical evaluations of the database show where operations have to be clarified in more detail or where the geometry of parts will have to be changed because of bottlenecks during the line operation.

An experimental system for distributed classroom education

This paper describes an experimental system for classroom-based tele-education based on IP multicast. It gives an overview of the system and describes how the system is designed to avoid a single central point of failure. The system supports locally controlled video mixing, provides simple floor arbitration without a central controller, and finally implements a new wavelet-based video compression scheme to achieve better video quality for large screen projection. The new network protocols involved are briefly described.

Quantitative analysis of DNA array autoradiographs

DNA arrays and chips are powerful new tools for gene expression profiling. Current arrays contain hundreds or thousands of probes and large scale sequencing and screening projects will likely lead to the creation of global genomic arrays. DNA arrays and chips will be key in understanding how genes respond to specific changes of environment and will also greatly assist in drug discovery and molecular diagnostics. To facilitate widespread realization of the quantitative potential of this approach, we have designed procedures and software which facilitate analysis of autoradiography films with accuracy comparable to phosphorimaging devices. Algorithms designed for analysis of DNA array autoradiographs incorporate 3-D peak fitting of features on films and estimation of local backgrounds. This software has a flexible grid geometry and can be applied to different types of DNA arrays, including custom arrays.

Working in the office of "Real Soon Now"

The "Office of Real Soon Now" is an ongoing experiment to see what it's like to use large-screen projection as our only computer display. We say "Real Soon Now" to contrast our experiment with the "Office of the Future", a project at the University of North Carolina that's building a much more sophisticated, laboratory-based environment in which multiple projectors seamlessly blend to display on most of the office surfaces. Our systems aren't nearly that fancy. Our idea was to experiment with systems we could build and operate within days. In our "Real Soon Now" offices, we use large-screen projection instead of conventional monitors. We've been using these systems for more than a year, and we'll never go back.

PCR/SSCP detects reliably and efficiently DNA sequence variations in large scale screening projects.

A simple and fast method with high reliability is necessary for the identification of mutations, polymorphisms and sequence variants (MPSV) within many genes and many samples, e.g. for clarifying the genetic background of individuals with multifactorial diseases. Here we review our experience with the polymerase chain reaction/single-strand conformation polymorphism (PCR/SSCP) analysis to identify MPSV in a number of genes thought to be involved in the pathogenesis of multifactorial neurological disorders, including autoimmune diseases like multiple sclerosis (MS) and neurodegenerative disorders like Parkinson s disease (PD). The method is based on the property of the DNA that the electrophoretic mobility of single stranded nucleic acids depends not only on their size but also on their sequence. The target sequences were amplified, digested into fragments ranging from 50-240 base pairs (bp), heat-denatured and analysed on native polyacrylamide (PAA) gels of different composition. The analysis of a great number of different PCR products demonstrates that the detection rate of MPSV depends on the fragment lengths, the temperature during electrophoresis and the composition of the gel. In general, the detection of MPSV is neither influenced by their location within the DNA fragment nor by the type of substitution, i.e., transitions or transversions. The standard PCR/SSCP system described here provides high reliability and detection rates. It allows the efficient analysis of a large number of DNA samples and many different genes.

Performance and function of a desktop viewer at Mayo Clinic Scottsdale.

A clinical viewing system was integrated with the Mayo Clinic Scottsdale picture archiving and communication system (PACS) for providing images and the report as part of the electronic medical record (EMR). Key attributes of the viewer include a single user log-on, an integrated patient centric EMR image access for all ordered examinations, prefetching of the most recent prior examination of the same modality, and the ability to provide comparison of current and past exams at the same time on the display. Other functions included preset windows, measurement tools, and multiformat display. Images for the prior 12 months are stored on the clinical server and are viewable in less than a second. Images available on the desktop include all computed radiography (CR), chest, magnetic resonance images (MRI), computed tomography (CT), ultrasound (U/S), nuclear, angiographic, gastrointestinal (GI) digital spots, and portable C-arm digital spots. Ad hoc queries of examinations from PACS are possible for those patients whose image may not be on the clinical server, but whose images reside on the PACS archive (10TB). Clinician satisfaction was reported to be high, especially for those staff heavily dependent on timely access to images, as well as those having heavy film usage. The desktop viewer is used for resident access to images. It is also useful for teaching conferences with large-screen projection without film. We report on the measurements of functionality, reliability, and speed of image display with this application.

Electronic Cinema — The REALLY Big Picture

AbstractRecent developments in large screen projection displays and image compression technology have brought the film‐less electronic cinema theatre closer to reality. This paper discusses technical requirements and alternative design approaches for an all‐digital electronic means for distribution and exhibition of motion pictures and other related programming. A cost‐effective complete system solution for processing, distributing and presenting cinema‐quality electronic programs originating as motion pictures is described.