272 research outputs found
Assessing UAS Flight Testing and It's Importance for Beyond-Line-of-Sight UAS Control in Cooperation with Partnering Organizations
From the 1st of June until the 21st of August, the internship has been conducted at NASA Ames Research Center as part of the Master of Space Studies at the International Space University. The main activities consisted of doing research on UAV flight-testing and the assessing of safety with respect to Beyond-Line-Of-Sight operations. Further activities consisted of accommodating international partners and potential partners at the NASA Ames site, in order to identify mutual interest and future collaboration. Besides those activities, the report describes the planning process of the ISU Space Coast Trip to 10 different space related companies on the west-coast of California. Key words: UAS, UAV, BLOS, Ames, ISU Tri
SBE-type metal-substituted aluminophosphates: detemplation and coordination chemistry
The detemplation process in Me-SBE (Me = Co^2+, Mg^2+, and Mn^2+) aluminophosphates was studied to elucidate materials stability and framework characteristics. In addition, the hydrothermal synthesis conditions were optimized to obtain materials with minimal phase impurities. This was accomplished by means of decreasing reaction temperature and increasing aging periods. Scanning electron microscopy analysis of the Mg- and Mn-SBE as-synthesized samples revealed square plates with truncated corner morphologies grown in aggregated fashion and contrasting with the previously reported hexagonal platelike morphology of Co-SBE. Cautious detemplation in vacuum, using an evacuation rate of 10 mmHg/s and a temperature of 648 K, resulted in surface areas of about 700, 500, and 130 m^2/g for Mg-, Co-, and Mn-SBE, respectively. Thermal gravimetric analysis and in situ high-temperature powder X-ray diffraction analyses indicate the frameworks for all of the SBE variants experienced collapse upon treatment with helium at temperatures above 700 K and subsequently formed an aluminophosphate trydimite dense phase. Detemplation in air at all times resulted in framework destruction during detemplation. In situ differential scanning calorimetry−powder X-ray diffraction data showed that the SBE frameworks experience breathing modes related to specific endothermic and exothermic scenarios during air treatment. Decomposition and elimination of the organic template during vacuum treatment was verified by Fourier transform infrared spectroscopy. X-ray photoelectron spectroscopy revealed that most of the Co atoms in vacuum-treated samples are in tetrahedral coordination, while the Mn atoms exhibit various coordination states. Ultraviolet-visible, electron paramagnetic resonance, and magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy corroborated the latter result in addition to providing evidence for the formation of Mn extra framework species. ^(27)Al MAS NMR spectra for vacuum-detemplated Mg-SBE samples prior to and after dehydration confirmed the reversible formation of aluminum octahedral sites. This, however, did not affect the porous nature of detemplated Mg-SBE samples as these are capable of adsorbing 19 water molecules per super cage at 298 K
Business intelligence systems and operational capability: an empirical analysis of high-tech sectors
202105 bchyAccepted ManuscriptRGC155009/15BPublishe
Interobserver variation in CD30 immunohistochemistry interpretation; consequences for patient selection for targeted treatment
AimsCD30 immunohistochemistry (IHC) in malignant lymphoma is used for selection of patients in clinical trials using brentuximab vedotin, an antibody drug-conjugate targeting the CD30 molecule. For reliable implementation in daily practice and meaningful selection of patients for clinical trials, information on technical variation and interobserver reproducibility of CD30 immunohistochemistry (IHC) staining is required. Methods and resultsWe conducted a three-round reproducibility assessment of CD30 scoring for categorised frequency and intensity, including a technical validation, a live polling' pre- and post-instruction scoring round and a web-based round including individual scoring with additional IHC information to mimic daily diagnostic practice. Agreement in all three scoring rounds was poor to fair ( = 0.12-0.35 for CD30-positive tumour cell percentage and = 0.16-0.41 for staining intensity), even when allowing for one category of freedom in percentage of tumour cell positivity ( = 0.30-0.61). The first round with CD30 staining performed in five independent laboratories showed objective differences in staining intensity. In the second round, approximately half the pathologists changed their opinion on CD30 frequency after a discussion on potential pitfalls, highlighting hesitancy in decision-making. Using fictional cut-off points for percentage of tumour cell positivity, agreement was still suboptimal ( = 0.35-0.60). ConclusionsLack of agreement in cases with heterogeneous expression is shown to influence patient eligibility for treatment with brentuximab vedotin, both in clinical practice and within the context of clinical trials, and limits the potential predictive value of the relative frequency of CD30-positive neoplastic cells for clinical response
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Commentary on the WHO classification of tumors of lymphoid tissues (2008): “Gray zone” lymphomas overlapping with Burkitt lymphoma or classical Hodgkin lymphoma
The 2008 WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues has introduced two new categories of high-grade B-cell lymphomas: entities in which features of diffuse large B-cell lymphoma (DLBCL) overlap with Burkitt lymphoma (DLBCL/BL) or classical Hodgkin lymphoma (DLBCL/HL). The DLBCL/BL category encompasses cases that resemble Burkitt lymphoma morphologically, but have one or more immunophenotypic or molecular genetic deviations that would exclude it from the BL category; conversely, some cases have immunophenotypic and/or genetic features of BL, but display cytologic variability unacceptable for BL. Many of the cases in the DLBCL/BL category contain a translocation of MYC as well as either BCL2 or BCL6 (so-called double-hit lymphomas) and have a very aggressive clinical behavior. The DLBCL/HL category encompasses lymphomas that exhibit the morphology of classical Hodgkin lymphoma but the immunophenotype of DLBCL, or vice versa. Most DLBCL/HL cases described present as mediastinal masses, but this category is not limited to mediastinal lymphomas. These new categories acknowledge the increasing recognition of cases that display mixed features of two well-established diseases. Whether the existence of such cases reflects shortcomings of our current diagnostic armamentarium or a true disease continuum in which such hybrid or intermediate neoplasms actually exist remains to be determined
Among B cell non-Hodgkin's lymphomas, MALT lymphomas express a unique antibody repertoire with frequent rheumatoid factor reactivity
We analyzed the structure of antigen receptors of a comprehensive panel of mature B non-Hodgkin's lymphomas (B-NHLs) by comparing, at the amino acid level, their immunoglobulin (Ig)VH-CDR3s with CDR3 sequences present in GenBank. Follicular lymphomas, diffuse large B cell lymphomas, Burkitt's lymphomas, and myelomas expressed a CDR3 repertoire comparable to that of normal B cells. Mantle cell lymphomas and B cell chronic lymphocytic leukemias (B-CLLs) expressed clearly restricted albeit different CDR3 repertoires. Lymphomas of mucosa-associated lymphoid tissues (MALTs) were unique as 8 out of 45 (18%) of gastric- and 13 out of 32 (41%) of salivary gland-MALT lymphomas expressed B cell antigen receptors with strong CDR3 homology to rheumatoid factors (RFs). Of note, the RF-CDR3 homology without exception included N-region–encoded residues in the hypermutated IgVH genes, indicating that they were stringently selected for reactivity with auto-IgG. By in vitro binding studies with 10 MALT lymphoma–derived antibodies, we showed that seven of these cases, of which four with RF-CDR3 homology, indeed possessed strong RF reactivity. Of one MALT lymphoma, functional proof for selection of subclones with high RF affinity was obtained. Interestingly, RF-CDR3 homology and t(11;18) appeared to be mutually exclusive features and RF-CDR3 homology was not encountered in any of the 19 pulmonary MALT lymphomas studied
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Commentary on the WHO classification of tumors of lymphoid tissues (2008): indolent B cell lymphomas
The 4th edition of the World Health Organization classification of tumors of hematopoietic and lymphoid tissues introduces many new items to the classification scheme of the so-called indolent B cell lymphomas. New proposed entities, such as splenic B cell lymphoma/leukemia, unclassifiable, splenic diffuse red pulp small B cell lymphoma, hairy cell leukemia variant, pediatric follicular lymphoma, and pediatric marginal zone lymphoma have been coined, and some definitions of established diseases, such as chronic lymphocytic leukemia or Waldenström’s macroglobulinemia have been revised. One aspect of major importance is the recent description of small clonal B cell populations, in part with a CLL phenotype, and their relationship to B-CLL. Some new subtypes or variants of follicular lymphoma with distinct clinicopathologic and/or molecular genetic characteristics have been described, including primary follicular lymphomas of the duodenum and pediatric follicular lymphomas. Furthermore, the impact of some probably early, or precursor lesions, such as follicular lymphoma in situ is discussed. Overall, we succinctly discuss the essential elements of the revisions made in the updated classification, and we identify potential opportunities for refinement of new or provisional categories in subsequent classifications
Translocation t(11;18)(q21;q21) in gastric B‐cell lymphomas
Translocation t(11;18)(q21;q21) is the most frequent chromosomal aberration reported in gastric mucosa-associated lymphoid tissue (MALT) lymphomas. Intriguingly, this translocation has been reported only rarely in diffuse large B-cell lymphomas; it has been proposed that t(11;18)-positive tumors rarely progress to diffuse large B-cell lymphomas. We examined the frequency of chromosomal translocation t(11;18)(q21;q21) in mucosa-associated lymphoid tissue lymphoma and diffuse large B-cell lymphoma of the stomach. Paraffin-embedded tissues from patients with gastric B-cell lymphomas were selected retrospectively. The presence of the t(11;18)(q21;q21) was determined using reverse transcriptase-polymerase chain reaction and/or fluorescence in situ hybridization. beta-Actin transcript was also determined to evaluate the integrity and efficiency of RNA (cDNA) recovery from paraffin-embedded tissues. We analyzed 53 gastric B-cell lymphomas (33 diffuse large B-cell and 20 mucosa-associated lymphoid tissue) obtained from Italy, the USA, or Japan. Beta-actin transcript was amplified in 50 cases (94%), including 19 mucosa-associated lymphoid tissue and 31 diffuse large B-cell lymphomas (five with mucosa-associated lymphoid tissue components). The t(11;18) translocation was detected in 19% (6 of 31) cases with diffuse large B-cell lymphoma versus 26% (five of 19) with mucosa-associated lymphoid tissue lymphoma (P = 0.72). One of five diffuse large B-cell lymphomas with a mucosa-associated lymphoid tissue component showed the t(11;18)(q21;q21). In conclusion, translocation t(11;18)(q21;q21) was found in both mucosa-associated lymphoid tissue lymphomas and diffuse large B-cell lymphomas of the stomach at approximately equivalent frequencies; its presence does not exclude progression to diffuse large B-cell lymphoma
Delineation of Chondroid Lipoma: An Immunohistochemical and Molecular Biological Analysis
Aims. Chondroid lipoma (CL) is a benign tumor that mimics a variety of soft tissue tumors and is characterized by translocation t(11;16). Here, we analyze CL and its histological mimics. Methods. CL (n = 4) was compared to a variety of histological mimics (n = 83) for morphological aspects and immunohistochemical features including cyclinD1(CCND1). Using FISH analysis, CCND1 and FUS were investigated as potential translocation partners. Results. All CLs were strongly positive for CCND1. One of 4 myoepitheliomas, CCND1, was positive. In well-differentiated lipomatous tumors and in chondrosarcomas, CCND1 was frequently expressed, but all myxoid liposarcomas were negative. FISH analysis did not give support for direct involvement of CCND1 and FUS as translocation partners. Conclusions. Chondroid lipoma is extremely rare and has several and more prevalent histological mimics. The differential diagnosis of chondroid lipomas can be unraveled using immunohistochemical and molecular support
Identifying Audiences of E-Infrastructures - Tools for Measuring Impact
Research evaluation should take into account the intended scholarly and non-scholarly audiences of the research output. This holds too for research infrastructures, which often aim at serving a large variety of audiences. With research and research infrastructures moving to the web, new possibilities are emerging for evaluation metrics. This paper proposes a feasible indicator for measuring the scope of audiences who use web-based e-infrastructures, as well as the frequency of use. In order to apply this indicator, a method is needed for classifying visitors to e-infrastructures into relevant user categories. The paper proposes such a method, based on an inductive logic program and a Bayesian classifier. The method is tested, showing that the visitors are efficiently classified with 90% accuracy into the selected categories. Consequently, the method can be used to evaluate the use of the e-infrastructure within and outside academia
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