65,005 research outputs found
The equivalence of two graph polynomials and a symmetric function
The U-polynomial, the polychromate and the symmetric function generalization of the Tutte polynomial due to Stanley are known to be equivalent in the sense that the coefficients of any one of them can be obtained as a function of the coefficients of any other. The definition of each of these functions suggests a natural way in which to strengthen them which also captures Tutte's universal V-function as a specialization. We show that the equivalence remains true for the strong functions thus
answering a question raised by Dominic Welsh
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A homing receptor-IgG chimera as a probe for adhesive ligands of lymph node high endothelial venules.
The binding of lymphocytes to high endothelial venules (HEV) within peripheral lymph nodes (pln) is thought to be mediated by a lectinlike adhesion molecule termed the pln homing receptor (pln HR). The cloning and sequencing of cDNAs encoding both murine and human pln HR revealed that these adhesion molecules contain protein motifs that are homologous to C-type or calcium dependent lectin domains as well as to epidermal growth factor (egf) and complement-regulatory protein domains. We have produced a novel, antibody-like form of the murine HR by joining the extracellular region of the receptor to a human IgG heavy chain. This antibody-like molecule is capable of recognizing carbohydrates, blocking the binding of lymphocytes to pln HEV, and serving as a histochemical reagent for the staining of pln HEV. This murine HR-IgG chimera should prove useful in analyzing the distribution of the HR ligand(s) in normal as well as in inflammatory states
The complement binding-like domains of the murine homing receptor facilitate lectin activity.
The leukocyte homing receptor (HR), the endothelial leukocyte adhesion molecule, and gmp140/platelet activation-dependent granule membrane protein are members of a family of adhesion molecules, termed the lectin cell adhesion molecules (LEC-CAMS) which are unified by a multi-domain structure containing a lectin motif, an epidermal growth factor-like (egf) motif, and variable numbers of a complement binding-like (CB) motif. Previous data have indicated a predominant role for the lectin motif in cell adhesion directed by the LEC-CAMS, although the egf-like domain of the HR may also play a potential role in cell binding. While the role(s) of the CB domains in the LEC-CAMS is currently not understood, they have been hypothesized to act as rigid spacers or stalks for lectin and perhaps, egf domain presentation. In this paper, we analyze the functional characteristics of murine HR-IgG chimeras containing the lectin, lectin plus egf, and lectin plus egf plus CB domains. The Mel 14 mAb, an adhesion blocking antibody which recognizes a conformational determinant in the N-terminus of the HR lectin domain, shows a significantly decreased affinity for a HR construct which lacks the CB motifs, consistent with the possibility that the CB domains are involved with lectin domain structure. In agreement with this conjecture, HR mutants lacking the CB domains show a profound decrease in lectin-specific interaction with the carbohydrate polyphosphomannan ester, suggesting that the changes in Mel 14 affinity for the lectin domain are reflected in lectin functionality. Various assays investigating the interactions between the HR deletion mutants and the peripheral lymph node high endothelium, including cell blocking, immunohistochemical staining, and radioactively labeled ligand binding, all showed that removal of the CB domains results in a lack of HR adhesive function. These results imply that the CB domains of the HR, and, by analogy, the other members of the LEC-CAM family, may play important structural roles involving induction of lectin domain conformation and resultant functionality
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Regimes of polymer behaviour in drop-on-demand ink-jetting
Three regimes of fast DoD jetting behaviour for solutions of mono-disperse linear polymers have been linked to the underlying polymer molecular chains and their fully extended length L in good solvents. This allows scaling laws in molecular weight to be predicted and applied to experimental jetting results from different DoD print heads. The higher extensional flows encountered in high speed jetting in viscous solvents can fully stretch linear molecules outside the nozzle, permitting jetting of higher polymer content than for purely elastic behaviour. These results are significant for DoD printing at raised jet speeds and will apply to any DoD print head jetting linear polymer solutions.This work was supported by EPSRC grant number RG5560
Rydberg-state-enabled deceleration and trapping of cold molecules
Hydrogen molecules in selected core-nonpenetrating Rydberg-Stark states have been decelerated from a mean initial velocity of 500m/s to zero velocity in the laboratory frame and loaded into a three-dimensional electrostatic trap. Trapping times, measured by pulsed electric field ionization of the trapped molecules, are found to be limited by collisional processes. As Rydberg states can be deexcited to the absolute ground state, the method can be applied to generate cold samples of a wide range of species. © 2009 The American Physical Society
Identification of a carbohydrate-based endothelial ligand for a lymphocyte homing receptor.
Lymphocyte attachment to high endothelial venules within lymph nodes is mediated by the peripheral lymph node homing receptor (pnHR), originally defined on mouse lymphocytes by the MEL-14 mAb. The pnHR is a calcium-dependent lectin-like receptor, a member of the LEC-CAM family of adhesion proteins. Here, using a soluble recombinant form of the homing receptor, we have identified an endothelial ligand for the pnHR as an approximately 50-kD sulfated, fucosylated, and sialylated glycoprotein, which we designate Sgp50 (sulfated glycoprotein of 50 kD). Recombinant receptor binding to this lymph node-specific glycoprotein requires calcium and is inhibitable by specific carbohydrates and by MEL-14 mAb. Sialylation of the component is required for binding. Additionally, the glycoprotein is precipitated by MECA-79, an adhesion-blocking mAb reactive with lymph node HEV. A related glycoprotein of approximately 90 kD (designated as Sgp90) is also identified
Building Data-Driven Pathways From Routinely Collected Hospital Data:A Case Study on Prostate Cancer
Background: Routinely collected data in hospitals is complex, typically heterogeneous, and scattered across multiple Hospital Information Systems (HIS). This big data, created as a byproduct of health care activities, has the potential to provide a better understanding of diseases, unearth hidden patterns, and improve services and cost. The extent and uses of such data rely on its quality, which is not consistently checked, nor fully understood. Nevertheless, using routine data for the construction of data-driven clinical pathways, describing processes and trends, is a key topic receiving increasing attention in the literature. Traditional algorithms do not cope well with unstructured processes or data, and do not produce clinically meaningful visualizations. Supporting systems that provide additional information, context, and quality assurance inspection are needed. Objective: The objective of the study is to explore how routine hospital data can be used to develop data-driven pathways that describe the journeys that patients take through care, and their potential uses in biomedical research; it proposes a framework for the construction, quality assessment, and visualization of patient pathways for clinical studies and decision support using a case study on prostate cancer. Methods: Data pertaining to prostate cancer patients were extracted from a large UK hospital from eight different HIS, validated, and complemented with information from the local cancer registry. Data-driven pathways were built for each of the 1904 patients and an expert knowledge base, containing rules on the prostate cancer biomarker, was used to assess the completeness and utility of the pathways for a specific clinical study. Software components were built to provide meaningful visualizations for the constructed pathways. Results: The proposed framework and pathway formalism enable the summarization, visualization, and querying of complex patient-centric clinical information, as well as the computation of quality indicators and dimensions. A novel graphical representation of the pathways allows the synthesis of such information. Conclusions: Clinical pathways built from routinely collected hospital data can unearth information about patients and diseases that may otherwise be unavailable or overlooked in hospitals. Data-driven clinical pathways allow for heterogeneous data (ie, semistructured and unstructured data) to be collated over a unified data model and for data quality dimensions to be assessed. This work has enabled further research on prostate cancer and its biomarkers, and on the development and application of methods to mine, compare, analyze, and visualize pathways constructed from routine data. This is an important development for the reuse of big data in hospitals
Does pleopod setation provide a measure of maturity in female southern rock lobsters Jasus edwardsii?
Processes affecting the estimation of the size at onset of maturity (SOM) using ovigerous setae were investigated in southern rock lobsters Jasus edwardsii. Comparison of estimates of SOM based on ovigerous setae in samples collected during summer months (December-March) with those based on the presence of external eggs from winter months (June-August) indicated that ovigerous setae provide an accurate classification of maturity. Females with partially developed setation on pleopods are frequently observed in research catch-sampling projects and their maturity status was unclear. Our results show that these females with partially developed setae are most appropriately classed as immature, based on comparison between estimates of SOM determined by presence of external eggs or setae. The seasonal timing of field sampling affected estimates of SOM based on ovigerous setae, though tag-recapture data indicated that this was not associated with a loss of setae during a second annual moult. Estimates of SOM for populations of Jasus edwardsii around Tasmania can be based on maturity classification using ovigerous setae but care should be taken to ensure that seasonal timing of sampling is consistent
Implementasi Kurikulum 2013 pada Sekolah Dasar di Kecamatan Pangkalan Koto Baru Kabupaten Lima Puluh Kota Provinsi Sumatera Barat
Implementation of Curriculum 2013 at the elementary school in Pangkalan Koto Baru experiencing various problems because according to socialize standardization is done twice or more. However for the socialization of teachers in the district of Koto new Base is only done once. So the faculty as a human resources do not understand how to implement the curriculum in 2013 in accordance with existing standards. Then the implementing organizations involved establish standard operating procedures for the implementation of the curriculum in 2013. Handbook as infrastructure is inadequate because of delays in the distribution of books of the government for four months. The purpose of this research was to identify and analyze how the implementation of the curriculum in 2013 at the elementary school in Pangkalan Koto Baru and the factors that influence the implementation of the curriculum in 2013.This research using Van Meter Van Horn theory which states that the successful implementation of a policy is the standard and policy objectives , resources, characteristics of the implementing organization , the communication between organizations , the attitude of the implementing policies and social environment , economic and political . This study used a qualitative exploratory methods , techniques of collecting data through observation and interviews where people that involved in this study as an informant.The results showed that the implementation of the curriculum in 2013 at the elementary school in Pangkalan Koto Baru has not been done optimally because there are still many weaknesses in the current curriculum in 2013 is implemented in Pangkalan Koto Baru. Inhibiting factors affecting the implementation of the curriculum in 2013 at the elementary school in Pangkalan Koto Baru is socialization which is not maximized , inadequate means and Standard Operating Procedure ( SOP ) which has not been established .Keywords : Implementation , Curriculum 2013, Elementary Schoo
Keyword-Based Delegable Proofs of Storage
Cloud users (clients) with limited storage capacity at their end can
outsource bulk data to the cloud storage server. A client can later access her
data by downloading the required data files. However, a large fraction of the
data files the client outsources to the server is often archival in nature that
the client uses for backup purposes and accesses less frequently. An untrusted
server can thus delete some of these archival data files in order to save some
space (and allocate the same to other clients) without being detected by the
client (data owner). Proofs of storage enable the client to audit her data
files uploaded to the server in order to ensure the integrity of those files.
In this work, we introduce one type of (selective) proofs of storage that we
call keyword-based delegable proofs of storage, where the client wants to audit
all her data files containing a specific keyword (e.g., "important"). Moreover,
it satisfies the notion of public verifiability where the client can delegate
the auditing task to a third-party auditor who audits the set of files
corresponding to the keyword on behalf of the client. We formally define the
security of a keyword-based delegable proof-of-storage protocol. We construct
such a protocol based on an existing proof-of-storage scheme and analyze the
security of our protocol. We argue that the techniques we use can be applied
atop any existing publicly verifiable proof-of-storage scheme for static data.
Finally, we discuss the efficiency of our construction.Comment: A preliminary version of this work has been published in
International Conference on Information Security Practice and Experience
(ISPEC 2018
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