525 research outputs found
A Reactive and Efficient Walking Pattern Generator for Robust Bipedal Locomotion
Available possibilities to prevent a biped robot from falling down in the
presence of severe disturbances are mainly Center of Pressure (CoP) modulation,
step location and timing adjustment, and angular momentum regulation. In this
paper, we aim at designing a walking pattern generator which employs an optimal
combination of these tools to generate robust gaits. In this approach, first,
the next step location and timing are decided consistent with the commanded
walking velocity and based on the Divergent Component of Motion (DCM)
measurement. This stage which is done by a very small-size Quadratic Program
(QP) uses the Linear Inverted Pendulum Model (LIPM) dynamics to adapt the
switching contact location and time. Then, consistent with the first stage, the
LIPM with flywheel dynamics is used to regenerate the DCM and angular momentum
trajectories at each control cycle. This is done by modulating the CoP and
Centroidal Momentum Pivot (CMP) to realize a desired DCM at the end of current
step. Simulation results show the merit of this reactive approach in generating
robust and dynamically consistent walking patterns
A method to provide high volume transaction outputs accessibility to vision Impaired using layout analysis
The Documents in the financial services, insurance, utilities, and government sectors
typically require a high volume of PDF documents to be generated which are stored for
presentment or archived for legal purposes. As high volume transactional output (HVTO)
demands put increasing pressure on online presentment capabilities, accessibility has become a
growing concern. In particular, access to these files proposes significant challenges when these
documents are presented to visually impaired people using assistive technologies (i.e. screen
readers). Since it is rare that all recipients are prepared to accept electronic delivery of their
documents, a large portion of the documents is still printed as PDFs. In an online billing system,
bills are sent to customers’ email accounts as attached PDF files or HTML links. These bills in the
most cases are neither accessible through assistive technologies nor useable by vision-impaired
customers. This paper provides a method for HVTO documents automatic transformation to an
accessible and navigable Mark-up format such as XML or Digital Accessible Information System
(DAISY)
P082: Beijing and non-Beijing genotypes detection of mycobacterium tuberculosis by melting curve analyzes
Practical segmentation methods for logical and geometric layout analysis to Improve scanned PDF accessibility to vision impaired
The use of electronic documents has rapidly increased in recent decades and the PDF is one the
most commonly used electronic document formats. A scanned PDF is an image and does not actually
contain any text. For the vision–impaired user who is dependent upon a screen reader to access this
information, this format is not useful. Thus addressing PDF accessibility through assistive technology
has now become an important concern. PDF layout analysis provides precious formatting information
that supports PDF component classification. This classification facilitates the tag generation. Accurate
tagging produces a searchable and navigable scanned PDF document. This paper describes several
practical segmentation methods which are easy to implement and efficient for PDF layout analysis so
that the scanned PDF document can be navigated or searched using assistive technologies
Genetic variability and differentiation of common Kilka fish (Clupeonella cultriventris Nordmann, 1840) in the southern coasts of Caspian Sea
A total of 120 samples of adult common Kilka fish (Clupeonella cultriventris) were collected during spring and summer from the southern coasts of Caspian Sea (Bandar Anzali and Babolsar). Fifteen sets of microsatellite primers were developed from Clupeidae being tested on genomic DNA of common Kilka. Allele frequency, observed and expected heterozygosity, FST, RST, FIS index were determined. Five primer sets as polymorphic loci were used to analyze the genetic variation in adults of the common Kilka population. Results revealed that average alleles per locus was 13.1 (range 5 to 22 alleles per locus in regions, Ne=9.5). All sampled regions contained private alleles. Average observed and expected heterozygosity was 0.348 and 0.877, respectively. Deviations from Hardy Weinberg equilibrium were observed in most cases. FST, RST and gene flow estimates in AMOVA and the genetic distance between populations indicated that the genetic difference among the studied populations was pronounced. The data generated in this study provide primary information on the genetic variation and differentiation in populations of Caspian common Kilka
Comparison of antibacterial activities of Ircinia mutans extracts in two different seasons from Kish Island, Persian Gulf, Iran
Sponges, which constitute the phylum Porifera, are the most primitive of the multicellular animals, among all marine organisms screened. Marine sponges produce the largest number of structurally diversified natural products. In this study we investigated in vitro antimicrobial activity of Ircinia mutans collected from the Kish Island in the Persian Gulf against strains of bacteria Escherichia coli (ATCC 15224), Pseudomonas aeruginosa (ATCC 25619), Staphylococcus aureus (ATCC 1764), and Bacillus subtilis spizizenii (ATCC 6633). Diethyl etter, methanol and aqueous extracts of sponge were evaluated by using the Bacterial Broth Dilution Method. The results showed that the aqueous extracts didn’t have any antibacterial activity. Minimum Inhibitory Concentrations (MIC) of the winter diethyl etter extract was 2 mg/ml for E.coli and 20 mg/ml for P. aeruginosa, whereas the summer diethyl etter extract and both of methanol extracts did not show any activity. The MIC and MBC (Minimum Bacterial Concentration) of summer diethyl etter extracts were 2 mg/ml and 3mg/ml against S. aureus; and 5mg/ml and 10mg/ml when tested on B. subtilis. The MIC and MBC of winter diethyl etter extracts were measured as 1.5 mg/ml and 2mg/ml against S. aurous; and 5mg/ml and 10mg/ml when examined on B. subtilis. Summer and winter methanol and aqueous extracts of I. mutans did not show any activity against these bacteria. Therefore secondary metabolite solutions in diethyl etter contain components with antibacterial properties and can be used as antibiotics products
A case of recurrent epilepsy-associated rosette-forming glioneuronal tumor with anaplastic transformation in the absence of therapy.
Rosette-forming glioneuronal tumor (RGNT) most commonly occurs adjacent to the fourth ventricle and therefore rarely presents with epilepsy. Recent reports describe RGNT occurrence in other anatomical locations with considerable morphologic and genetic overlap with the epilepsy-associated dysembryoplastic neuroepithelial tumor (DNET). Examples of RGNT or DNET with anaplastic change are rare, and typically occur in the setting of radiation treatment. We present the case of a 5-year-old girl with seizures, who underwent near total resection of a cystic temporal lobe lesion. Pathology showed morphologic and immunohistochemical features of RGNT, albeit with focally overlapping DNET-like patterns. Resections of residual or recurrent tumor were performed 1 year and 5 years after the initial resection, but no adjuvant radiation or chemotherapy was given. Ten years after the initial resection, surveillance imaging identified new and enhancing nodules, leading to another gross total resection. This specimen showed areas similar to the original tumor, but also high-grade foci with oligodendroglial morphology, increased cellularity, palisading necrosis, microvascular proliferation, and up to 13 mitotic figures per 10 high power fields. Ancillary studies the status by sequencing showed wild-type of the isocitrate dehydrogenase 1 (IDH1), IDH2, and human histone 3.3 (H3F3A) genes, and BRAF studies were negative for mutation or rearrangement. Fluorescence in situ hybridization (FISH) showed codeletion of 1p and 19q limited to the high-grade regions. By immunohistochemistry there was loss of nuclear alpha-thalassemia mental retardation syndrome, X-linked (ATRX) expression only in the high-grade region. Next-generation sequencing showed an fibroblast growth factor receptor receptor 1 (FGFR1) kinase domain internal tandem duplication in three resection specimens. ATRX mutation in the high-grade tumor was confirmed by sequencing which showed a frameshift mutation (p.R1427fs), while the apparent 1p/19q-codeletion by FISH was due to loss of chromosome arm 1p and only partial loss of 19q. Exceptional features of this case include the temporal lobe location, 1p/19q loss by FISH without true whole-arm codeletion, and anaplastic transformation associated with ATRX mutation without radiation or chemotherapy
Exploring wind direction and SO2 concentration by circular-linear density estimation
The study of environmental problems usually requires the description of
variables with different nature and the assessment of relations between them.
In this work, an algorithm for flexible estimation of the joint density for a
circular-linear variable is proposed. The method is applied for exploring the
relation between wind direction and SO2 concentration in a monitoring station
close to a power plant located in Galicia (NW-Spain), in order to compare the
effectiveness of precautionary measures for pollutants reduction in two
different years.Comment: 17 pages, 7 figures, 2 table
Monodisperse Cylindrical Micelles and Block Comicelles of Controlled Length in Aqueous Media
Cylindrical
block copolymer micelles have shown considerable promise
in various fields of biomedical research. However, unlike spherical
micelles and vesicles, control over their dimensions in biologically
relevant solvents has posed a key challenge that potentially limits
in depth studies and their optimization for applications. Here, we
report the preparation of cylindrical micelles of length in the wide
range of 70 nm to 1.10 μm in aqueous media with narrow length
distributions (length polydispersities <1.10). In our approach,
an amphiphilic linear-brush block copolymer, with high potential for
functionalization, was synthesized based on poly(ferrocenyldimethylsilane)-<i>b</i>-poly(allyl glycidyl ether) (PFS-<i>b</i>-PAGE)
decorated with triethylene glycol (TEG), abbreviated as PFS-<i>b</i>-(PEO-<i>g</i>-TEG). PFS-<i>b</i>-(PEO-<i>g</i>-TEG) cylindrical micelles of controlled length with low
polydispersities were prepared in <i>N</i>,<i>N</i>-dimethylformamide using small seed initiators via living crystallization-driven
self-assembly. Successful dispersion of these micelles into aqueous
media was achieved by dialysis against deionized water. Furthermore,
B–A–B amphiphilic triblock comicelles with PFS-<i>b</i>-poly(2-vinylpyridine) (P2VP) as hydrophobic “B”
blocks and hydrophilic PFS-<i>b</i>-(PEO-<i>g</i>-TEG) “A” segments were prepared and their hierarchical
self-assembly in aqueous media studied. It was found that superstructures
formed are dependent on the length of the hydrophobic blocks. Quaternization
of P2VP was shown to cause the disassembly of the superstructures,
resulting in the first examples of water-soluble cylindrical multiblock
comicelles. We also demonstrate the ability of the triblock comicelles
with quaternized terminal segments to complex DNA and, thus, to potentially
function as gene vectors
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