500 research outputs found
Determinants Associated to Zeta Matrices of Posets
We consider the matrix , where the entries of
are the values of the zeta function of the finite poset . We give a
combinatorial interpretation of the determinant of and establish
a recursive formula for this determinant in the case in which is a boolean
algebra.Comment: 14 pages, AMS-Te
Some theoretical results on semiconductor spherical quantum dots
We use an improved version of the standard effective mass approximation model
to describe quantum effects in nanometric semiconductor Quantum Dots (QDs).
This allows analytic computation of relevant quantities to a very large extent.
We obtain, as a function of the QD radius, in precise domains of validity, the
QD excitonic ground state energy and its Stark and Lamb shifts. Finally, the
Purcell effect in QDs is shown to lead to potential QD-LASER emitting in the
range of visible light
The liver X receptor pathway is highly upregulated in rheumatoid arthritis synovial macrophages and potentiates TLR-driven cytokine release
<p>Objectives: Macrophages are central to the inflammatory processes driving rheumatoid arthritis (RA) synovitis. The molecular pathways that are induced in synovial macrophages and thereby promote RA disease pathology remain poorly understood.</p>
<p>Methods: We used microarray to characterise the transcriptome of synovial fluid (SF) macrophages compared with matched peripheral blood monocytes from patients with RA (n=8).</p>
<p>Results: Using in silico pathway mapping, we found that pathways downstream of the cholesterol activated liver X receptors (LXRs) and those associated with Toll-like receptor (TLR) signalling were upregulated in SF macrophages. Macrophage differentiation and tumour necrosis factor α promoted the expression of LXRα. Furthermore, in functional studies we demonstrated that activation of LXRs significantly augmented TLR-driven cytokine and chemokine secretion.</p>
<p>Conclusions: The LXR pathway is the most upregulated pathway in RA synovial macrophages and activation of LXRs by ligands present within SF augments TLR-driven cytokine secretion. Since the natural agonists of LXRs arise from cholesterol metabolism, this provides a novel mechanism that can promote RA synovitis.</p>
Europeanising advisory expertise: The role of 'independent, objective and transparent' scientific advice in agri-biotech regulation
Since various crises of food safety in the European Union (EU), institutional reforms have been designed to regain public confidence in regulatory decisions and their expert basis. By Europeanising advisory expertise, the European Food Safety Authority (EFSA) was also meant to help harmonise 'science-based regulation' and thus facilitate EU decisions. In evaluating agri-biotech products during 2003-2005, however, the EFSA procedure extended previous expert disagreements rather than overcome them. EFSA was designed to demonstrate that expert advice would be 'independent, objective and transparent�; yet tensions arose between expert experience versus independence, between transparency versus objectivity, and between harmonisation versus precaution. These conflicts have been shaped by the dominant problem-diagnosis, which favours a narrow expert consensus within a specific policy view. Alternative problem-diagnoses suggest that expertise should instead be pluralised, so that norms and uncertainties become more explicit. Pressure for EU reform manifests tensions between the dominant and alternative problem-diagnoses
Deep-water macroalgae from the Canary Islands: new records and biogeographical relationships
Due to the geographical location and paleobiogeography of the Canary Islands, the
seaweed flora contains macroalgae with different distributional patterns. In this contribution, the biogeographical relations of several new records of deep-water macroalgae recently collected around the Canarian archipelago are discussed. These are Bryopsidella neglecta (Berthotd) Rietema,Discosporangium mesarthrocarpum (Meneghini) Hauck, Hincksia onslowensis (Amsler et Kapraun)P.C. Silva, Syringoderma floridana Henry, Peyssonnelia harveyana J. Agardh, Cryptonemia seminervis(C. Agardh) J. Agardh, Botryodadia wynnei Ballantine, Gloiocladia blomquistii (Searles) R. E.Norris, PIahchrysis peltata (W. R. Taylor) P. Huv4 et H. Huv4, Leptofauchea brasiliensis Joly, and Sarcodiotheca divaricata W. R. Taylor. These new records, especially those in the Florideophyceae,support the strong affinity of the Canary Islands seaweed flora with the warm-temperate Mediterranean-Atlantic region. Some species are recorded for the first time from the east coast of the Atlantic Ocean, enhancing the biogeographic relations of the Canarian marine flora with that of the western Atlantic regions
Motif Minang Kaluak Paku Kacang Balimbiang pada Busana Kasual
Minangkabau sebagai salah satu suku bangsa yang mengisi kekhasan
budaya Indonesia memiliki warisan budaya yang terpencar dalam berbagai aspek
kehidupannya. Salah satu warisan budaya adalah seni ukir. Seni ukir yang
dikembangkan dengan mengambil ide dari alam memiliki makna-makna filosofi
bagi kehidupan masyarakat Minangkabau. Semua jenis ukiran yang dipahatkan di
Rumah Gadang menunjukkan unsur penting pembentuk budaya Minangkabau
bercerminkan kepada apa yang ada di alam. Salah satu ukiran pada rumah gadang
yaitu kaluak paku. Kaluak paku adalah nama salah satu motif ukiran dalam adat
Minangkabau. Berasal dari motif gulungan (kelukan/kaluak) pada ujung tanaman
pakis (paku) yang masih muda. Ukiran kaluak paku rumah gadang melambangkan
tanggung jawab seorang lelaki dalam adat Minangkabau kepada generasi penerus,
sebagai ayah dari anak-anaknya dan sebagai mamak dari kemenakan (keponakan).
Ukiran rumah gadang kaluak paku minangkabau inilah yang menjadi sumber ide
penciptaan busana pada tugas akhir ini.
Pada Penciptaan karya ini menggunakan beberapa metode, yaitu metode
pendekatan estetis dan ergonomis, metode pengumpulan data dengan studi
pustaka, dan motode penciptaan dengan teori Gustami Sp 3 tahap 6 Langkah.
Dalam proses pembuatan karya dibutuhkan beberapa data, cara pengumpulan data
acuan berdasarkan pengumpulan data pustaka yaitu berupa buku, jurnal pada
media sosial, serta aplikasi pada smartphone seperti pinterest. Data yang
dikumpulkan yang paling utama adalah gambar bentuk visual dari ukiran tanaman
kaluak paku minangkabau dan busana kasual.
Penciptaan karya yang dihasilkan yaitu berupa 8 busana kasual. Siluet pada
kesuluruhan hasil karya yaitu memiliki siluet A yang mengembang pada bagian
bawah. Pada penciptaan karya ini menggunakan bahan utama primisima.
Perpaduan warna yang diterapkan menggunakan warna khas minangkabau yang
diambil dari warna bendera adatnya “marawa” yaitu merah, hitam, dan kuning.
Karya- karya yang dihasilkan dengan penggunaan warna tersebut sangat sesuai
dengan tema yang mengangkat ukiran rumah gadang kaluak paku minangkabau.
Kata Kunci : Minang, Kaluak Paku Kacang Balimbiang, Kasua
Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment
journal_title: Environmental Research Letters article_type: lett article_title: Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment copyright_information: © 2016 IOP Publishing Ltd license_information: cc-by Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. date_received: 2016-05-12 date_accepted: 2016-08-10 date_epub: 2016-09-1
The Structure of Hydrogenase-2 from <i>Escherichia coli</i>:Implications for H<sub>2</sub> -Driven Proton Pumping
Under anaerobic conditions Escherichia coli is able to metabolize molecular hydrogen via the action of several [NiFe]-hydrogenase enzymes. Hydrogenase-2, which is typically present in cells at low levels during anaerobic respiration, is a periplasmic-facing membrane-bound complex that functions as a proton pump to convert energy from H2 oxidation into a proton gradient; consequently, its structure is of great interest. Empirically, the complex consists of a tightly-bound core catalytic module, comprising large (HybC) and small (HybO) subunits, which is attached to an Fe-S protein (HybA) and an integral membrane protein, HybB. To date, efforts to gain a more detailed picture have been thwarted by low native expression levels of hydrogenase-2 and the labile interaction between HybOC and HybA/HybB subunits. In this paper we describe a new over-expression system that has facilitated determination of high-resolution crystal structures of HybOC and, hence, a prediction of the quaternary structure of the HybOCAB complex
Structural and Functional Loss in Restored Wetland Ecosystems
In restored wetland ecosystems with apparently natural hydrology and biological structure, biogeochemical function may remain degraded, even a century after restoration efforts
A Fresh Variational-Analysis Look at the Positive Semidefinite Matrices World
International audienceEngineering sciences and applications of mathematics show unambiguously that positive semidefiniteness of matrices is the most important generalization of non-negative real num- bers. This notion of non-negativity for matrices has been well-studied in the literature; it has been the subject of review papers and entire chapters of books. This paper reviews some of the nice, useful properties of positive (semi)definite matrices, and insists in particular on (i) characterizations of positive (semi)definiteness and (ii) the geometrical properties of the set of positive semidefinite matrices. Some properties that turn out to be less well-known have here a special treatment. The use of these properties in optimization, as well as various references to applications, are spread all the way through. The "raison d'ĂŞtre" of this paper is essentially pedagogical; it adopts the viewpoint of variational analysis, shedding new light on the topic. Important, fruitful, and subtle, the positive semidefinite world is a good place to start with this domain of applied mathematics
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