219 research outputs found
Slippage Features
In this report, we present a novel feature detection technique for unstructured point clouds. We introduce a generalized concept of geometric features that detects locally uniquely identifiable keypoints as centroids of area with locally minimal slippage. We extend the concept to multiple scales and extract features using multi-scale mean shift clustering. In order to validate matches between feature points, we employ a two stage technique that first sorts out unlikely matches, followed by an approximate alignment between remaining features by a rotational cross-correlation analysis and a local iterative closest point (ICP) registration. The resulting residuals are then used as final similarity measure. The proposed combination of techniques results in a robust and reliable correspondence detection technique that yields registration results in situations where previous techniques are not able to detect usable feature correspondences. We provide a detailed empirical analysis of the method, and apply the technique to global registration, symmetry detection and deformable matching problems
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Gas Flow Shaping via Novel Modular Nozzle System (MoNoS) Augments kINPen-Mediated Toxicity and Immunogenicity in Tumor Organoids
Medical gas plasma is an experimental technology for anticancer therapy. Here, partial gas ionization yielded reactive oxygen and nitrogen species, placing the technique at the heart of applied redox biomedicine. Especially with the gas plasma jet kINPen, anti-tumor efficacy was demonstrated. This study aimed to examine the potential of using passive flow shaping to enhance the medical benefits of atmospheric plasma jets (APPJ). We used an in-house developed, proprietary Modular Nozzle System (MoNoS; patent-pending) to modify the flow properties of a kINPen. MoNoS increased the nominal plasma jet-derived reactive species deposition area and stabilized the air-plasma ratio within the active plasma zone while shielding it from external flow disturbances or gas impurities. At modest flow rates, dynamic pressure reduction (DPR) adapters did not augment reactive species deposition in liquids or tumor cell killing. However, MoNoS operated at kINPen standard argon fluxes significantly improved cancer organoid growth reduction and increased tumor immunogenicity, as seen by elevated calreticulin and heat-shock protein expression, along with a significantly spurred cytokine secretion profile. Moreover, the safe application of MoNoS gas plasma jet adapters was confirmed by their similar-to-superior safety profiles assessed in the henâs egg chorioallantoic membrane (HET-CAM) coagulation and scar formation irritation assay
Unraveling spatiotemporal variability of arbuscular mycorrhizal fungi in a temperate grassland plot
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Goldmann, K., Boeddinghaus, R. S., Klemmer, S., Regan, K. M., Heintz-Buschart, A., Fischer, M., Prati, D., Piepho, H., Berner, D., Marhan, S., Kandeler, E., Buscot, F., & Wubet, T. Unraveling spatiotemporal variability of arbuscular mycorrhizal fungi in a temperate grassland plot. Environmental Microbiology, 22(3),(2020): 873-888, doi:10.1111/1462-2920.14653.Soils provide a heterogeneous environment varying in space and time; consequently, the biodiversity of soil microorganisms also differs spatially and temporally. For soil microbes tightly associated with plant roots, such as arbuscular mycorrhizal fungi (AMF), the diversity of plant partners and seasonal variability in trophic exchanges between the symbionts introduce additional heterogeneity. To clarify the impact of such heterogeneity, we investigated spatiotemporal variation in AMF diversity on a plot scale (10 Ă 10 m) in a grassland managed at low intensity in southwest Germany. AMF diversity was determined using 18S rDNA pyrosequencing analysis of 360 soil samples taken at six time points within a year. We observed high AMF alphaâ and betaâdiversity across the plot and at all investigated time points. Relationships were detected between spatiotemporal variation in AMF OTU richness and plant species richness, root biomass, minimal changes in soil texture and pH. The plot was characterized by high AMF turnover rates with a positive spatiotemporal relationship for AMF betaâdiversity. However, environmental variables explained only â20% of the variation in AMF communities. This indicates that the observed spatiotemporal richness and community variability of AMF was largely independent of the abiotic environment, but related to plant properties and the cooccurring microbiome.We thank the managers of the three Exploratories, Kirsten ReichelâJung, Swen Renner, Katrin Hartwich, Sonja Gockel, Kerstin Wiesner, and Martin Gorke for their work in maintaining the plot and project infrastructure; Christiane Fischer and Simone Pfeiffer for giving support through the central office, Michael Owonibi and Andreas Ostrowski for managing the central data base, and Eduard Linsenmair, Dominik Hessenmöller, Jens Nieschulze, ErnstâDetlef Schulze, Wolfgang W. Weisser and the late Elisabeth Kalko for their role in setting up the Biodiversity Exploratories project. The work has been funded by the DFG Priority Program 1374 âInfrastructureâBiodiversityâExploratoriesâ (BU 941/22â1, BU 941/22â3, KA 1590/8â2, KA 1590/8â3). Field work permits were issued by the responsible state environmental office of BadenâWĂŒrttemberg (according to § 72 BbgNatSchG). Likewise, we kindly thank Beatrix Schnabel, Melanie GĂŒnther and Sigrid HĂ€rtling for 454 sequencing in Halle. AHB gratefully acknowledges the support of the German Centre for Integrative Biodiversity Research (iDiv) HalleâJenaâLeipzig funded by the German Research Foundation (FZT 118). Authors declare no conflict of interests
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Medical Gas Plasma Treatment in Head and Neck CancerâChallenges and Opportunities
Despite progress in oncotherapy, cancer is still among the deadliest diseases in the Western world, emphasizing the demand for novel treatment avenues. Cold physical plasma has shown antitumor activity in experimental models of, e.g., glioblastoma, colorectal cancer, breast carcinoma, osteosarcoma, bladder cancer, and melanoma in vitro and in vivo. In addition, clinical case reports have demonstrated that physical plasma reduces the microbial contamination of severely infected tumor wounds and ulcerations, as is often seen with head and neck cancer patients. These antimicrobial and antitumor killing properties make physical plasma a promising tool for the treatment of head and neck cancer. Moreover, this type of cancer is easily accessible from the outside, facilitating the possibility of several rounds of topical gas plasma treatment of the same patient. Gas plasma treatment of head and neck cancer induces diverse effects via the deposition of a plethora of reactive oxygen and nitrogen species that mediate redox-biochemical processes, and ultimately, selective cancer cell death. The main advantage of medical gas plasma treatment in oncology is the lack of adverse events and significant side effects compared to other treatment modalities, such as surgical approaches, chemotherapeutics, and radiotherapy, making plasma treatment an attractive strategy for the adjuvant and palliative treatment of head and neck cancer. This review outlines the state of the art and progress in investigating physical plasma as a novel treatment modality in the therapy of head and neck squamous cell carcinoma
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Medical Gas Plasma Treatment in Head and Neck CancerâChallenges and Opportunities
Despite progress in oncotherapy, cancer is still among the deadliest diseases in the Western world, emphasizing the demand for novel treatment avenues. Cold physical plasma has shown antitumor activity in experimental models of, e.g., glioblastoma, colorectal cancer, breast carcinoma, osteosarcoma, bladder cancer, and melanoma in vitro and in vivo. In addition, clinical case reports have demonstrated that physical plasma reduces the microbial contamination of severely infected tumor wounds and ulcerations, as is often seen with head and neck cancer patients. These antimicrobial and antitumor killing properties make physical plasma a promising tool for the treatment of head and neck cancer. Moreover, this type of cancer is easily accessible from the outside, facilitating the possibility of several rounds of topical gas plasma treatment of the same patient. Gas plasma treatment of head and neck cancer induces diverse effects via the deposition of a plethora of reactive oxygen and nitrogen species that mediate redox-biochemical processes, and ultimately, selective cancer cell death. The main advantage of medical gas plasma treatment in oncology is the lack of adverse events and significant side effects compared to other treatment modalities, such as surgical approaches, chemotherapeutics, and radiotherapy, making plasma treatment an attractive strategy for the adjuvant and palliative treatment of head and neck cancer. This review outlines the state of the art and progress in investigating physical plasma as a novel treatment modality in the therapy of head and neck squamous cell carcinoma
Fall history and associated factors among adults living with HIV-1 in the Cape Winelands, South Africa : an exploratory investigation
CITATION: Berner, K., et al. 2019. Fall history and associated factors among adults living with HIV-1 in the Cape Winelands, South Africa : an exploratory investigation. Open Forum Infectious Diseases, 6(10):ofz401, doi:10.1093/ofid/ofz401.The original publication is available at https://academic.oup.com/ofidPublication of this article was funded by the Stellenbosch University Open Access Fund.Background. People with HIV-1 (PWH) exhibit a high fall incidence and increased fracture risk. As little is known about fall
frequency and associated factors in PWH residing in lower-middle-income countries (LMIC), we investigated fall frequency, bone
quality, and factors associated with fall history in a South African cohort.
Methods. Fifty PWH without obvious predisposing factors for mobility impairments attending 2 public primary care clinics in
the Western Cape region participated. Demographic, clinical, and physical performance data were collected. Falls were assessed retrospectively
over 12 months. Mobility and balance were evaluated using a physical performance battery. Bone mineral density was
screened using quantitative ultrasound (QUS). Associations between variables and falls grouping were analyzed using chi-square
tests, t tests, and Mann-Whitney U tests, and effect sizes (ES) were calculated.
Results. Thirty-four percent of PWH (median age, 36.6 years) reported falling during the past year, and 41.2% of fallers reported
multiple falls. Fallers had more mobility problems (P = .013), higher fear of falling (P = .007), higher fracture history (P = .003),
worse balance performance (P < .001), higher proportions of detectable viral loads (P = .021), and poorer bone quality (P = .040).
Differences were of medium to large ES.
Conclusions. This exploratory study is the first to show that relatively young South African PWH without obvious predisposing
factors for gait and balance impairments experience falls. The observed fall-associated factors warrant further research using larger
samples and longitudinal designs to ascertain fall predictors within this population.https://academic.oup.com/ofid/article/6/10/ofz401/5584296Publisher's versio
Human Immunoglobulin M Memory B Cells Controlling Streptococcus pneumoniae Infections Are Generated in the Spleen
Splenectomized and asplenic patients have a high incidence of infections by encapsulated bacteria and do not respond to polysaccharide vaccines. To understand whether the absence of the spleen is associated with a defined B cell defect, we analyzed B cell subsets in the peripheral blood. We found that a population of B cells known as immunoglobulin (Ig)M memory is lacking in patients without spleen. The absence of IgM memory B cells correlates with an impaired immune response to encapsulated bacteria not only in splenectomized patients, but also in individuals with an intact spleen. We show that the physiological and transient predisposition to pneumococcal infections of young children (0â2 yr) is associated with the lack of circulating IgM memory B cells and of serum antipolysaccharide IgM. We also demonstrate that IgM memory B cells are undetectable in a fraction of patients with common variable immunodeficiency, who have recurrent and invasive infections by encapsulated bacteria. IgM memory B cells, therefore, require the spleen for their generation and/or survival and are responsible for the protection against encapsulated bacteria
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