Motion compensation of Synthetic Aperture Radar

Synthetic aperture radar (SAR) is a digital signal processing technique which enhances the azimuth resolution of a radar image using the target doppler history created by the motion of the radar platform. If the platform deviates from a constant velocity, straight-line path then image quality is lost and image details become unfocused. Motion compensation (MOCO) is a technique in which the position and attitude of the platform is recorded or estimated and then used to correct the scene\u27s doppler history as if a straight-line, constant velocity path had been taken. Brigham Young University\u27s interferometric synthetic aperture radar (yINSAR) was flown on a Cessna Skymaster which experienced significant motion due to the aircraft\u27s small frame. But using multiple motion sensors, such as an intertial measurement device and various GPS units, the motion can be compensated for. This report discusses some basic SAR theory, SAR motion compensation, a brief description of YINSAR and measurement devices, the MOCO algorithm, and some radar image results

Flexible access to conformationally-locked bicyclic morpholines

A preparatively accessible route to a series of conformationally-locked bicyclic morpholines has been developed. This flexible approach allows for diversification in order for a small array of lead-like scaffolds to be synthesised from readily available key building blocks

A metamorphic inorganic framework that can be switched between eight single-crystalline states

The design of highly flexible framework materials requires organic linkers, whereas inorganic materials are more robust but inflexible. Here, by using linkable inorganic rings made up of tungsten oxide (P8W48O184) building blocks, we synthesized an inorganic single crystal material that can undergo at least eight different crystal-to-crystal transformations, with gigantic crystal volume contraction and expansion changes ranging from −2,170 to +1,720 Å3 with no reduction in crystallinity. Not only does this material undergo the largest single crystal-to-single crystal volume transformation thus far reported (to the best of our knowledge), the system also shows conformational flexibility while maintaining robustness over several cycles in the reversible uptake and release of guest molecules switching the crystal between different metamorphic states. This material combines the robustness of inorganic materials with the flexibility of organic frameworks, thereby challenging the notion that flexible materials with robustness are mutually exclusive

Protection of CpG islands from DNA methylation is DNA-encoded and evolutionarily conserved.

DNA methylation is a repressive epigenetic modification that covers vertebrate genomes. Regions known as CpG islands (CGIs), which are refractory to DNA methylation, are often associated with gene promoters and play central roles in gene regulation. Yet how CGIs in their normal genomic context evade the DNA methylation machinery and whether these mechanisms are evolutionarily conserved remains enigmatic. To address these fundamental questions we exploited a transchromosomic animal model and genomic approaches to understand how the hypomethylated state is formed in vivo and to discover whether mechanisms governing CGI formation are evolutionarily conserved. Strikingly, insertion of a human chromosome into mouse revealed that promoter-associated CGIs are refractory to DNA methylation regardless of host species, demonstrating that DNA sequence plays a central role in specifying the hypomethylated state through evolutionarily conserved mechanisms. In contrast, elements distal to gene promoters exhibited more variable methylation between host species, uncovering a widespread dependence on nucleotide frequency and occupancy of DNA-binding transcription factors in shaping the DNA methylation landscape away from gene promoters. This was exemplified by young CpG rich lineage-restricted repeat sequences that evaded DNA methylation in the absence of co-evolved mechanisms targeting methylation to these sequences, and species specific DNA binding events that protected against DNA methylation in CpG poor regions. Finally, transplantation of mouse chromosomal fragments into the evolutionarily distant zebrafish uncovered the existence of a mechanistically conserved and DNA-encoded logic which shapes CGI formation across vertebrate species

A Population-Based Cohort Study of Mycobacterium tuberculosis Beijing Strains: An Emerging Public Health Threat in an Immigrant-Receiving Country?

Mycobacterium tuberculosis Beijing strains are frequently associated with tuberculosis outbreaks and drug resistance. However, contradictory evidence and limited study generalizability make it difficult to foresee if the emergence of Beijing strains in high-income immigrant-receiving countries poses an increased public health threat. The purpose of this study was to determine if Beijing strains are associated with high risk disease presentations relative to other strains within Canada.This was a retrospective population-based study of culture-confirmed active TB cases in a major immigrant-receiving province of Canada in 1991 through 2007. Of 1,852 eligible cases, 1,826 (99%) were successfully genotyped. Demographic, clinical, and mycobacteriologic surveillance data were combined with molecular diagnostic data. The main outcome measures were site of disease, lung cavitation, sputum smear positivity, bacillary load, and first-line antituberculosis drug resistance.A total of 350 (19%) patients had Beijing strains; 298 (85%) of these were born in the Western Pacific. Compared to non-Beijing strains, Beijing strains were significantly more likely to be associated with polyresistance (aOR 1.8; 95% CI 1.0-3.3; p = 0.046) and multidrug-resistance (aOR 3.4; 1.0-11.3; p = 0.049). Conversely, Beijing strains were no more likely than non-Beijing strains to be associated with respiratory disease (aOR 1.3; 1.0-1.8; p = 0.053), high bacillary load (aOR 1.2; 0.6-2.7), lung cavitation (aOR 1.0; 0.7-1.5), immediately life-threatening forms of tuberculosis (aOR 0.8; 0.5-1.6), and monoresistance (aOR 0.9; 0.6-1.3). In subgroup analyses, Beijing strains only had a significant association with multidrug-resistant tuberculosis (aOR 6.1; 1.2-30.4), and an association of borderline significance with polyresistant tuberculosis (aOR 1.8; 1.0-3.5; p = 0.062), among individuals born in the Western Pacific.Other than an increased risk of polyresistant or multidrug-resistant tuberculosis, Beijing strains appear to pose no more of a public health threat than non-Beijing strains within a high-income immigrant-receiving country

Breaking the Curve with CANDELS: A Bayesian Approach to Reveal the Non-Universality of the Dust-Attenuation Law at High Redshift

Dust attenuation affects nearly all observational aspects of galaxy evolution, yet very little is known about the form of the dust-attenuation law in the distant Universe. Here, we model the spectral energy distributions (SEDs) of galaxies at z = 1.5--3 from CANDELS with rest-frame UV to near-IR imaging under different assumptions about the dust law, and compare the amount of inferred attenuated light with the observed infrared (IR) luminosities. Some individual galaxies show strong Bayesian evidence in preference of one dust law over another, and this preference agrees with their observed location on the plane of infrared excess (IRX, $L_{\text{TIR}}/L_{\text{UV}}$) and UV slope ($\beta$). We generalize the shape of the dust law with an empirical model, $A_{\lambda,\delta}=E(B-V)\ k_\lambda\ (\lambda/\lambda_V)^\delta$ where $k_\lambda$ is the dust law of Calzetti et al. (2000), and show that there exists a correlation between the color excess ${E(B-V)}$ and tilt $\delta$ with ${\delta=(0.62\pm0.05)\log(E(B-V))}$+ ${(0.26~\pm~0.02)}$. Galaxies with high color excess have a shallower, starburst-like law, and those with low color excess have a steeper, SMC-like law. Surprisingly, the galaxies in our sample show no correlation between the shape of the dust law and stellar mass, star-formation rate, or $\beta$. The change in the dust law with color excess is consistent with a model where attenuation is caused by by scattering, a mixed star-dust geometry, and/or trends with stellar population age, metallicity, and dust grain size. This rest-frame UV-to-near-IR method shows potential to constrain the dust law at even higher ($z>3$) redshifts.Comment: 20 pages, 18 figures, resubmitted to Ap

The Use of Global System of Mobile Communication (GSM) Among University Students in Malaysia

This study examines the use of the Global System of Mobile Communication (GSM) among University students in Malaysia. The survey approach was used in data collection from a sample population from University Teknologi Malaysia. Fifty undergraduate and post graduate students were sampled at the university library. Results from a multiple regression analysis shows that there is a significant relationship between age, monthly income/allowance of respondents, marital status and rate of calls made and received per day (P<0.05). Gender and mode of study were found to be insignificant (P>0.05).Results from t test equally indicate that the respondents do not vary in their perception on benefits derivable from the use of GSM (t = -.483, P >0.05).Majority of the respondents also agreed that they use GSM to contact their lecturers, course mates, parents, siblings and sending of short message services (SMS).The study conclude with discussions on findings which would be relevant to education policy makers and other interest partie

In situ readout of DNA barcodes and single base edits facilitated by in vitro transcription

Molecular barcoding technologies that uniquely identify single cells are hampered by limitations in barcode measurement. Readout by sequencing does not preserve the spatial organization of cells in tissues, whereas imaging methods preserve spatial structure but are less sensitive to barcode sequence. Here we introduce a system for image-based readout of short (20-base-pair) DNA barcodes. In this system, called Zombie, phage RNA polymerases transcribe engineered barcodes in fixed cells. The resulting RNA is subsequently detected by fluorescent in situ hybridization. Using competing match and mismatch probes, Zombie can accurately discriminate single-nucleotide differences in the barcodes. This method allows in situ readout of dense combinatorial barcode libraries and single-base mutations produced by CRISPR base editors without requiring barcode expression in live cells. Zombie functions across diverse contexts, including cell culture, chick embryos and adult mouse brain tissue. The ability to sensitively read out compact and diverse DNA barcodes by imaging will facilitate a broad range of barcoding and genomic recording strategies

Plasma Membrane Profiling Reveals Upregulation of ABCA1 by Infected Macrophages Leading to Restriction of Mycobacterial Growth.

The plasma membrane represents a critical interface between the internal and extracellular environments, and harbors multiple proteins key receptors and transporters that play important roles in restriction of intracellular infection. We applied plasma membrane profiling, a technique that combines quantitative mass spectrometry with selective cell surface aminooxy-biotinylation, to Bacille Calmette-Guérin (BCG)-infected THP-1 macrophages. We quantified 559 PM proteins in BCG-infected THP-1 cells. One significantly upregulated cell-surface protein was the cholesterol transporter ABCA1. We showed that ABCA1 was upregulated on the macrophage cell-surface following infection with pathogenic mycobacteria and knockdown of ABCA1 resulted in increased mycobacterial survival within macrophages, suggesting that it may be a novel mycobacterial host-restriction factor.Medical Research Council (Clinician Scientist Fellowship), Tsinghua University, Wellcome Trust (Senior Fellowship (Grant ID: 108070/Z/15/Z)), National Institute for Health Research (Academic Clinical Fellowship), China Scholarship CouncilThis is the final version of the article. It first appeared from Frontiers via http://dx.doi.org/10.3389/fmicb.2016.0108

Art therapy after stroke: Evidence and a need for further research

This is the post-print version of the final paper published in The Arts in Psychotherapy. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2012 Elsevier B.V.This review presents available evidence regarding the benefits of art therapy and therapeutic arts interventions for stroke survivors. Whilst available evidence is very limited, it suggests that art therapy may address many of the diverse cognitive, emotional and functional needs of people disabled by stroke. Attention, spatial processing, sequencing and planning seem to improve among those who persist with art therapy. Use of the stroke-affected limb may increase. Several studies report improvements in social interaction, and emotional expression. Most published reports offer single case examples, which are idiographic and illuminating. Nonetheless, the brevity of these reports, the reliance on therapist's own accounts, and uncertainties surrounding case selection make generalization of the findings uncertain. There is a pressing need for multi-method research studies. These could use quantitative standardized scales to explore changes in stroke survivors’ physical and emotional functioning, and qualitative enquiry to gain the insights of stroke survivors concerning the art therapy process. Such research designs might help to establish a better recognized role for art therapy within multidisciplinary stroke rehabilitation programs