668 research outputs found
A REVISION OF ISEILEMA (GRAMINEAE) IN MALESIA
VELDKAMP, J. F. 2016. A revision of Iseilema (Gramineae) in Malesia. Reinwardtia 15(2): 123 – 127. — There are three very rare and localized species in Malesia; one from Java is new. Notes on some other Southeast Asian species are given
AEGOPOGON (GRAMINEAE) IN MALESIA
AeyopoyoiL ceucliroides Willd. var. cenchroides is recorded for the first time from Malesian area based on a collection from Mt. Michael (Papuu New Guinea). A description is provided
The Projective Line Over the Finite Quotient Ring GF(2)[]/ and Quantum Entanglement I. Theoretical Background
The paper deals with the projective line over the finite factor ring
GF(2)[]/. The line is endowed with 18
points, spanning the neighbourhoods of three pairwise distant points. As
is not a local ring, the neighbour (or parallel) relation is
not an equivalence relation so that the sets of neighbour points to two distant
points overlap. There are nine neighbour points to any point of the line,
forming three disjoint families under the reduction modulo either of two
maximal ideals of the ring. Two of the families contain four points each and
they swap their roles when switching from one ideal to the other; the points of
the one family merge with (the image of) the point in question, while the
points of the other family go in pairs into the remaining two points of the
associated ordinary projective line of order two. The single point of the
remaining family is sent to the reference point under both the mappings and its
existence stems from a non-trivial character of the Jacobson radical, , of the ring. The factor ring is isomorphic to GF(2)
GF(2). The projective line over features nine
points, each of them being surrounded by four neighbour and the same number of
distant points, and any two distant points share two neighbours. These
remarkable ring geometries are surmised to be of relevance for modelling
entangled qubit states, to be discussed in detail in Part II of the paper.Comment: 8 pages, 2 figure
MISCELLANEOUS BOTANICAL NOTES XXVI
Description of the pod of the type tree of Ormosia incerta Koord. (reduced to 0. psnangensis Ridl.) from Java. Reduction of the genus Trifidacanthus Merr. (Legum.) to Desmodium; one new combination necessary. The genus Platyspermation Guillaumin described from New Caledonia in Myrtaeeae, suggested to belong to Saxifragaceae-Escallonioidsae. Juncus bufonius L. recorded as introduced on Mt Kinabalu. Two Fimbristylis species recorded new for the Northern Territory, Australia; Oreobolus kukenthalii Steen. recorded from Mt Muln, Sarawak
Sulfotyrosine Recognition as Marker for Druggable Sites in the Extracellular Space
Chemokine signaling is a well-known agent of autoimmune disease, HIV infection, and cancer. Drug discovery efforts for these signaling molecules have focused on developing inhibitors targeting their associated G protein-coupled receptors. Recently, we used a structure-based approach directed at the sulfotyrosine-binding pocket of the chemokine CXCL12, and thereby demonstrated that small molecule inhibitors acting upon the chemokine ligand form an alternative therapeutic avenue. Although the 50 members of the chemokine family share varying degrees of sequence homology (some as little as 20%), all members retain the canonical chemokine fold. Here we show that an equivalent sulfotyrosine-binding pocket appears to be conserved across the chemokine superfamily. We monitored sulfotyrosine binding to four representative chemokines by NMR. The results suggest that most chemokines harbor a sulfotyrosine recognition site analogous to the cleft on CXCL12 that binds sulfotyrosine 21 of the receptor CXCR4. Rational drug discovery efforts targeting these sites may be useful in the development of specific as well as broad-spectrum chemokine inhibitors
NOTES ON RAFFLESIA (RAFFLESIACEAE) IN SUMATRA WITH A NEW RECORD RAFFLESIA GADUTENSIS MEIJER
MAHYUNI, R., KUSUMA,Y. W. C., WIHERMANTO & VELDKAMP, J. F. 2015. Notes on Rafflesia (Rafflesiaceae) in Sumatra with a new record Rafflesia gadutensis Meijer. Reinwardtia 14(2): 317 - 322. -- Pulau Mursala is a small island west of the Sibolga, Tapanuli Tengah District, North Sumatra, Indonesia. The occurrence of the genus Rafflesia (Rafflesiaceae) there has never been reported before. However, during a visit in April 2013 three populations are located close together with more than twenty buds and some rotting blooming flowers, Tetrastigma sp. was detected. Field observations could be made and material was collected for comparison with that in the Herbarium Bogoriense (BO). It was concluded that they are R. gadutensis Meijer, which is known from Padang, Ulu Gadut. Notes on its morphology are given. The distribution of species is discussed
A peptide mimic of the chemotaxis inhibitory protein of Staphylococcus aureus: towards the development of novel anti-inflammatory compounds
Complement factor C5a is one of the most powerful pro-inflammatory agents involved in recruitment of leukocytes, activation of phagocytes and other inflammatory responses. C5a triggers inflammatory responses by binding to its G-protein-coupled C5a-receptor (C5aR). Excessive or erroneous activation of the C5aR has been implicated in numerous inflammatory diseases. The C5aR is therefore a key target in the development of specific anti-inflammatory compounds. A very potent natural inhibitor of the C5aR is the 121-residue chemotaxis inhibitory protein of Staphylococcus aureus (CHIPS). Although CHIPS effectively blocks C5aR activation by binding tightly to its extra-cellular N terminus, it is not suitable as a potential anti-inflammatory drug due to its immunogenic properties. As a first step in the development of an improved CHIPS mimic, we designed and synthesized a substantially shorter 50-residue adapted peptide, designated CHOPS. This peptide included all residues important for receptor binding as based on the recent structure of CHIPS in complex with the C5aR N terminus. Using isothermal titration calorimetry we demonstrate that CHOPS has micromolar affinity for a model peptide comprising residues 7–28 of the C5aR N terminus including two O-sulfated tyrosine residues at positions 11 and 14. CD and NMR spectroscopy showed that CHOPS is unstructured free in solution. Upon addition of the doubly sulfated model peptide, however, the NMR and CD spectra reveal the formation of structural elements in CHOPS reminiscent of native CHIPS
Computational Model for Urban Growth Using Socioeconomic Latent Parameters
Land use land cover changes (LULCC) are generally modeled using multi-scale
spatio-temporal variables. Recently, Markov Chain (MC) has been used to model
LULCC. However, the model is derived from the proportion of LULCC observed over
a given period and it does not account for temporal factors such as
macro-economic, socio-economic, etc. In this paper, we present a richer model
based on Hidden Markov Model (HMM), grounded in the common knowledge that
economic, social and LULCC processes are tightly coupled. We propose a HMM
where LULCC classes represent hidden states and temporal fac-tors represent
emissions that are conditioned on the hidden states. To our knowledge, HMM has
not been used in LULCC models in the past. We further demonstrate its
integration with other spatio-temporal models such as Logistic Regression. The
integrated model is applied on the LULCC data of Pune district in the state of
Maharashtra (India) to predict and visualize urban LULCC over the past 14
years. We observe that the HMM integrated model has improved prediction
accuracy as compared to the corresponding MC integrated modelComment: 12 page
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