92 research outputs found
Developing programming environments for programmable bricks
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (leaf 32).by Kuo Ching Hsu.M.Eng
Friedrichs extensions for a class of singular discrete linear Hamiltonian systems
This paper is concerned with the characterizations of the Friedrichs
extension for a class of singular discrete linear Hamiltonian systems. The
existence of recessive solutions and the existence of the Friedrichs extension
are proved under some conditions. The self-adjoint boundary conditions are
obtained by applying the recessive solutions and then the characterization of
the Friedrichs extension is obtained in terms of boundary conditions via linear
independently recessive solutions
A Neutrosophic Approach Based on TOPSIS Method to Image Segmentation
Neutrosophic set (NS) is a formal framework proposed recently. NS can not only describe the incomplete information in the decision-making system but also depict the uncertainty and inconsistency, so it has applied successfully in several fields such as risk assessment, fuzzy decision and image segmentation. In this paper, a new neutrosophic approach based on TOPSIS method, which can make full use of NS information, is proposed to separate the graphics. Firstly, the image is transformed into the NS domain. Then, two operations, a modified alpha-mean and the beta-enhancement operations are used to enhance image edges and to reduce uncertainty. At last, the segmentation is achieved by the TOPSIS method and the modified fuzzy c-means (FCM). Simulated images and real images are illustrated that the proposed method is more effective and accurate in image segmentation
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Genomic regions, cellular components and gene regulatory basis underlying pod length variations in cowpea (V. unguiculata L. Walp).
Cowpea (V. unguiculata L. Walp) is a climate resilient legume crop important for food security. Cultivated cowpea (V. unguiculata L) generally comprises the bushy, short-podded grain cowpea dominant in Africa and the climbing, long-podded vegetable cowpea popular in Asia. How selection has contributed to the diversification of the two types of cowpea remains largely unknown. In the current study, a novel genotyping assay for over 50 000 SNPs was employed to delineate genomic regions governing pod length. Major, minor and epistatic QTLs were identified through QTL mapping. Seventy-two SNPs associated with pod length were detected by genome-wide association studies (GWAS). Population stratification analysis revealed subdivision among a cowpea germplasm collection consisting of 299 accessions, which is consistent with pod length groups. Genomic scan for selective signals suggested that domestication of vegetable cowpea was accompanied by selection of multiple traits including pod length, while the further improvement process was featured by selection of pod length primarily. Pod growth kinetics assay demonstrated that more durable cell proliferation rather than cell elongation or enlargement was the main reason for longer pods. Transcriptomic analysis suggested the involvement of sugar, gibberellin and nutritional signalling in regulation of pod length. This study establishes the basis for map-based cloning of pod length genes in cowpea and for marker-assisted selection of this trait in breeding programmes
Near-Term Quantum Computing Techniques: Variational Quantum Algorithms, Error Mitigation, Circuit Compilation, Benchmarking and Classical Simulation
Quantum computing is a game-changing technology for global academia, research
centers and industries including computational science, mathematics, finance,
pharmaceutical, materials science, chemistry and cryptography. Although it has
seen a major boost in the last decade, we are still a long way from reaching
the maturity of a full-fledged quantum computer. That said, we will be in the
Noisy-Intermediate Scale Quantum (NISQ) era for a long time, working on dozens
or even thousands of qubits quantum computing systems. An outstanding
challenge, then, is to come up with an application that can reliably carry out
a nontrivial task of interest on the near-term quantum devices with
non-negligible quantum noise. To address this challenge, several near-term
quantum computing techniques, including variational quantum algorithms, error
mitigation, quantum circuit compilation and benchmarking protocols, have been
proposed to characterize and mitigate errors, and to implement algorithms with
a certain resistance to noise, so as to enhance the capabilities of near-term
quantum devices and explore the boundaries of their ability to realize useful
applications. Besides, the development of near-term quantum devices is
inseparable from the efficient classical simulation, which plays a vital role
in quantum algorithm design and verification, error-tolerant verification and
other applications. This review will provide a thorough introduction of these
near-term quantum computing techniques, report on their progress, and finally
discuss the future prospect of these techniques, which we hope will motivate
researchers to undertake additional studies in this field.Comment: Please feel free to email He-Liang Huang with any comments,
questions, suggestions or concern
Biomineralization of a calcifying ureolytic bacterium Microbacterium sp. GM-1
Background: Biomineralization is a significant process performed by
living organisms in which minerals are produced through the hardening
of biological tissues. Herein, we focus on calcium carbonate
precipitation, as part of biomineralization, to be used in applications
for environmental protection, material technology, and other fields. A
strain GM-1, Microbacterium sp. GM-1, isolated from active sludge,
was investigated for its ability to produce urease and induce calcium
carbonate precipitation in a metabolic process. Results: It was
discovered that Microbacterium sp. GM-1 resisted high concentrations of
urea up to 60 g/L. In order to optimize the calcification process of
Microbacterium sp. GM-1, the concentrations of Ni2+ and urea, pH value,
and culture time were analyzed through orthogonal tests. The favored
calcite precipitation culture conditions were as follows: the
concentration of Ni2+ and urea were 50 \u3bcM and 60 g/L,
respectively, pH of 10, and culture time of 96 h. Using X-ray
diffraction analysis, the calcium carbonate polymorphs produced by
Microbacterium sp. GM-1 were proven to be mainly calcite. Conclusions:
The results of this research provide evidence that Microbacterium sp.
GM-1 can biologically induce calcification and suggest that strain GM-1
may play a potential role in the synthesis of new biominerals and in
bioremediation or biorecovery
Effect of Ermiao Fang with Xixin (Herba Asari Mandshurici) on bone marrow stem cell directional homing to a focal zone in an osteoarthritis rat model
AbstractObjectiveTo investigate the effects of Ermiao Fang (EM) with medical guide Xixin (Herba Asari Mandshurici) (HAM) on bone marrow stem cell migration to a focal zone in osteoarthritis (OA) rats.MethodsOA rats were induced by arthrectomy and assigned to sham-operated, model, EM, or EM plus HAM groups. All rats were injected with recombinant human granulocyte colony-stimulating factor 30 μg • kg−1 • d−1 for 7 days and treated with EM or EM plus HAM at 1.6 or 1.9 g • kg−1 • d−1 for 3 or 6 weeks, respectively. Chondrocyte apoptosis and cartilage matrix components were tested by transferase-mediated deoxyuridine triphosphate-biotin nick end labeling assay and special staining. Levels of interleukin-1 beta (IL-1β) tumor necrosis factor alpha (TNF-α) nitric oxide (NO), and inducible nitric oxide synthase (iNOS) in serum were detected by enzyme-linked immunosorbent assay or radioimmunoassay. Matrix metalloproteinases (MMPs)-13, tissue inhibitors of metalloproteinases (TIMPs)-1, Bromodeoxyuridine (BrdU), cluster of differentiation 34 (CD34), and stromal cell-derived factor 1 (SDF-1) were measured by immunohistochemical assay.ResultsThe EM and EM plus HAM groups had significantly less cartilage damage and synovium inflammation the model group. Moreover, the EM and EM plus HAM groups had less chondrocyte apoptosis and more proteoglycan and collagen content than the model group. The EM and EM plus HAM groups had obviously higher MMPs-13 and TIMPs-1 expression in the cartilage than the model group. Moreover, the two formula groups had less release of IL-1β, TNF-α, NO, and iNOS than model group. Importantly, the expressions of BrdU, CD34, and SDF-1 in cartilage were significantly higher in the EM and EM plus HAM-Medtreated rats than model group. Notably, the EM plus HAM treatment seemed to have the greatest effects.ConclusionsHAM improves the therapeutic effects of EM on OA rats by enhancing BMSC directional homing to the focal zone
Pregnancy outcomes following natural conception and assisted reproduction treatment in women who received COVID-19 vaccination prior to conception: a population-based cohort study in China
IntroductionThe coronavirus disease-2019 (COVID-19) pandemic has swept across the world and continues to exert serious adverse effects on vulnerable populations, including pregnant women and neonates. The vaccines available at present were designed to prevent infection from COVID-19 strains and control viral spread. Although the incidence of pregnancy cycle outcomes are not likely to increase patients vaccinated prior to pregnancy compared with unvaccinated patients based on our knowledge of vaccination safety, there is no specific evidence to support this hypothesis. Therefore, the current study aimed to investigate the association between maternal vaccination prior to conception and pregnancy outcomes.MethodsWe retrospectively analyzed 2,614 women who received prenatal care and delivered in the Obstetrical Department of The First Affiliated Hospital of Anhui Medical University between February 2022 and November 2022. Of the 1,380 eligible pregnant women, 899 women who had received preconception vaccination were assigned to a vaccine group and 481 women who were not vaccinated were control group. Of the enrolled patients, 291 women received fertility treatment (141 vaccinated women, 150 unvaccinated women). The primary outcomes were pregnancy complications (hypothyroidism, gestational diabetes mellitus, pregnancy-induced hypertension, polyhydramnios, oligohydramnios, premature rupture of membranes and postpartum hemorrhage), obstetric outcomes (preterm birth rate, cesarean section rate) and neonatal outcomes (birth-weight, body length, low-birth-weight rate, rate of congenital defects, neonatal mortality and admission to the neonatal intensive care unit).ResultsThere was no significant difference in the incidence of complications during pregnancy and delivery when compared between the vaccine group and control group in either univariate- or multivariate-models. The type of vaccine was not associated with the odds of adverse pregnancy outcome. Among the women with infertility treatment, the vaccinated group and the unvaccinated group had similar pregnancy outcomes.ConclusionWomen who received COVID-19 vaccination prior to conception had similar maternal and neonatal outcomes as women who were unvaccinated. Our findings indicate that COVID-19 vaccinations can be safely administered prior to pregnancy in women who are planning pregnancy or assisted reproductive treatment. During new waves of COVID-19 infection, women who are planning pregnancy should be vaccinated as soon as possible to avoid subsequent infections
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