An O(n) invariant rank 1 convex function that is not polyconvex

An O(n) invariant nonnegative rank 1 convex function of linear growth is given that is not polyconvex. This answers a recent question [8, p. 182] and [5]. The polyconvex hull of the function is calculated explicitly if n = 2:

A hőmérséklet hatása a növényi RNS interferencia hatékonyságára = The effect of temperature on RNA interference in higher plants

A hőmérséklet hatása a növényi RNS interferencia hatékonyságára Programunk célja a növényi RNS interferencia (RNAi) rendszer hőmérsékletfüggésének vizsgálata volt. Igazoltuk, hogy a növényi RNAi rendszer egyes útvonalai erősen hőmérsékletfüggőek, így pl. a transzgén-, illetve vírus-indukálta RNAi válaszok alacsony hőmérsékleten alig működnek, míg normál hőmérsékleten ezek a rendszerek igen aktívak. Kimutattuk, hogy a transzgénekről, illetve vírusokról származó, az RNAi rendszer által generált rövid RNS-ek (siRNS-ek) szintje a hőmérséklet emelésével gyorsan nő. Ismert, hogy a növény-vírus kapcsolatok jelentős részében a tünetek alacsony hőmérsékleten erősek, míg magas hőmérsékleten gyengék. Igazoltuk, hogy ennek oka az, hogy a vírus-indukálta RNAi rendszer -a növények leghatékonyabb antivirális rendszere- hidegben alig működik, így a tünetek felerősödnek, a víruskártétel jelentős. Ugyanakkor melegben a hatékony RNAi rendszer tünetcsökkenéshez, vírusellenállósághoz vezet. A transzgénikus növények jelentős részénél a transzgénikus fenotípus a transzgén-indukálta RNAi rendszeren alapszik. Bizonyítottuk, hogy alacsony hőmérsékleten a transzgén-indukálta RNAi rendszeren alapuló transzgénikus fenotípusok, pl antiszensz gátlás, vírusellenállóság, elveszhetnek. Kimutattuk azt is, hogy megfelelő transzgén konstrukciók (fordított ismétlődést tartalmazó konstrukciók) használatával ez a veszély csökkenthető, azaz a transzgénikus fenotípusok alacsony hőmérsékleten is stabilak maradnak. | The effect of temperature on RNA interference in higher plants The aim of our project was to study the effect of temperature on efficiency of RNA interference (RNAi) system of higher plants. We have shown that certain plant RNAi pathways, as transgene- or virus- induced RNAi pathways are inhibited at low temperature, while these patways work efficiently at normal temperature. Indeed, the levels of RNAi generated transgene or virus derived short RNAs (siRNAs) are dramatically reduced at low temperature. Previously, it has been reported that in cold, viral infections of plants lead to strong symptoms and that outbreaks of viral diseases are frequent. By contrast, at high temperature the symptoms are masked, plants recover quickly. We show that viral symptoms are strong in cold because virus induced plant RNAi (the most important antiviral sytem of plants) is inefficient, whereas at high temperature the efficient RNAi can protect plants. Transgenic phenotypes of many transgenic plants are depend on transgene induced RNAi. We have demonstrated that in cold, transgenic phenotypes -as antisense inactivation or virus resistance- that depend on trangene induced RNAi are dramatically weakened. Importantly, if inverted repeat containing constructs are used, trangenic phenotypes are stable even at low temperature

Majorisation with applications to the calculus of variations

This paper explores some connections between rank one convexity, multiplicative quasiconvexity and Schur convexity. Theorem 5.1 gives simple necessary and sufficient conditions for an isotropic objective function to be rank one convex on the set of matrices with positive determinant. Theorem 6.2 describes a class of possible non-polyconvex but multiplicative quasiconvex isotropic functions. This class is not contained in a well known theorem of Ball (6.3 in this paper) which gives sufficient conditions for an isotropic and objective function to be polyconvex. We show here that there is a new way to prove directly the quasiconvexity (in the multiplicative form). Relevance of Schur convexity for the description of rank one convex hulls is explained.Comment: 13 page

Növényi RNS degradációs rendszerek: a nonsense-mediated decay rendszer molekuláris biológiája = RNA degradation systems in plants: the molecular biology of nonsense-mediated decay system

A program célja a növényi Nonsense-mediated mRNA decay (NMD) rendszer molekuláris biológiájának megismerése volt. Az NMD egy ősi eukarióta minőségbiztosítási rendszer, amely felismeri és lebontja a korai stop kodonokat (PTC) tartalmazó mRNS-eket, ezáltal megelőzi a csonka, domináns-negatív mutáns fehérjék képződését. A program során kimutattuk, hogy a növényi NMD rendszer PTC-ként ismer fel minden stop kodont, amely utána 3'UTR régió szokatlanul hosszú, vagy ahol a 3'UTR-ban intron található. Azonosítottuk a növényi NMD rendszer 6 transz faktorát, és kimutattuk, hogy a kétféle NMD cisz elem felismerés csak részben átfedő génkészletet igényel. Igazoltuk, hogy a PTC tartalmú növényi transzkriptek kétféle úton bomolhatnak le, az SMG-7, illetve a UPF1 irányította útvonalon. Kimutattuk, hogy az utóbbi XRN4 5'-3' exonukleázt igényel. Munkánk során bizonyítottuk, hogy a növényi NMD autoregulált, az SMG-7 NMD faktort az NMD negatívan regulálja. Végül eredményeink alapján egy új eukarióta NMD evolúciós modellt dolgoztunk ki. | The aim of this project was to understand the molecular basis of plant Nonsense-mediated mRNA decay (NMD) system. NMD is an ancient eukaryotic quality control system that identifies and degrades mRNAs containing premature termination codons (PTC), thereby preventing the accumulation of truncated dominant-negative mutant proteins. During this project we have shown that plant NMD system identifies any stop codon as a PTC if the 3'UTR is unusually long or if the 3' UTR contains an intron. We have identified 6 NMD trans factors and shown that the two NMD cis elements identification system requires overlapping but not identical gene sets. We have demonstrated that PTC containing mRNAs can be degraded by two pathways, one is mediated by SMG-7 and another is controlled by UPF1. XRN4 exonuclease is required only for the UPF1 mediated pathway. We have shown that plant NMD is an autoregulated system as SMG-7 NMD trans factor is negatively regulated by NMD. Finally, we have elaborated a new model for the evolution of eukaryotic NMD systems

Is It Reasonable? Reasonable and Unreasonable Accommodations for Occupational Therapy Students in Clinical Settings

Despite the growing number of graduate students with disabilities, little is known about what accommodations are considered reasonable in various occupational therapy fieldwork settings. This study explores which accommodations fieldwork educators perceive as reasonable or unreasonable for occupational therapy students with disabilities. Snowball sampling methodology was used to distribute a virtual survey, using a descriptive design. One hundred and sixty-two occupational therapists and occupational therapy assistants answered questions relating to demographic information, clinical experience supervising fieldwork students, and their clinical judgement regarding commonly requested accommodations. Using a quantitative approach, the accommodations deemed most reasonable were allowing the use of adaptive equipment (n = 156, reasonable: 96.3%) and permission to excuse oneself from the unit to maintain health (n = 152, reasonable: 93.83%). The accommodations considered the most unreasonable were the use of an intermediary to perform physical tasks (n = 82, unreasonable: 50.62%) and the use of an American Sign Language interpreter (n = 42, unreasonable: 24.93%). Clinicians in rehabilitation most often responded “reasonable” in response to an accommodation (n = 24, reasonable: 80.20%), while those who worked in outpatient pediatrics selected “unreasonable” most often (n = 4, unreasonable: 13.51%). This preliminary data provides stakeholders information about accommodations, creating opportunities to support students with disabilities in their pursuit of becoming clinicians. This will help to better fulfill American Occupational Therapy Association\u27s vision of inclusivity and equitability

A mutant Escherichia coli that attaches peptidoglycan to lipopolysaccharide and displays cell wall on its surface

The lipopolysaccharide (LPS) forms the surface-exposed leaflet of the outer membrane (OM) of Gram-negative bacteria, an organelle that shields the underlying peptidoglycan (PG) cell wall. Both LPS and PG are essential cell envelope components that are synthesized independently and assembled by dedicated transenvelope multiprotein complexes. We have identified a point-mutation in the gene for O-antigen ligase (WaaL) in Escherichia coli that causes LPS to be modified with PG subunits, intersecting these two pathways. Synthesis of the PG-modified LPS (LPS*) requires ready access to the small PG precursor pool but does not weaken cell wall integrity, challenging models of precursor sequestration at PG assembly machinery. LPS* is efficiently transported to the cell surface without impairing OM function. Because LPS* contains the canonical vancomycin binding site, these surface-exposed molecules confer increased vancomycin-resistance by functioning as molecular decoys that titrate the antibiotic away from its intracellular target. This unexpected LPS glycosylation fuses two potent pathogen-associated molecular patterns (PAMPs). DOI: http://dx.doi.org/10.7554/eLife.05334.00

Generation of Simulation Based Operational Database for an Acid Gas Removal Plant with Automatic Calculations

Computer aided process design is improving with newer and newer tools. One of such tools is the automatic calculation technique that enables the combination of different software tools to enhance the efficiency of the calculations. In our research work Aspen HYSYS model of a petrochemical plant is built in order to simulate responses of an existing plant to the changes in the composition and amount of feed material. The Aspen HYSYS is connected to Microsoft Excel program; simu-lated operational data are stored in an operational database and transported to Excel for further analysis. The automatic calculation completed with the two software tools mutually strengthens their merits and results in enhanced insight into the operational features of any plant. Comparison of the projected input parameters of the petrochemical plant studied shows that the extension of the plant is badly needed. Cash-flow analysis suggests that the extension is profitable