bluuebunny/crossref_metadata_2025_split huggingface dataset:
Very large dielectric response from ferroelectric nanocapacitor films due to collective surface and strain relaxation effects
Authors: Misirlioglu I. B. , Yildiz M. 
Published: November 2013

Dependence of the dielectric response of ferroelectrics on defect types, particularly those with long range strain fields in confined geometries have been often mentioned, especially in interpreting experimental results in films. However, detailed discussions on the mechanisms with which defects alter properties, particularly in the presence of interfaces imposing certain boundary conditions, are seldom made. Here, we studied the thickness dependence of transition temperatures and dielectric response of Metal/BaTiO3/Metal ferroelectric nanocapacitor structures grown on SrTiO3 using a phenomenological approach accounting for the equations of electrostatics and semiconductors. Relaxation of the misfit strain via misfit dislocations amplify the surface effects in films below a critical thickness and favor electrical domains leading to very large dielectric responses in this regime. Thin film structures with relaxed misfit strain in this work are fully depleted in the presence of moderate densities of impurities ( ∼ 1025 m −3). This is due to the reduction of polarization amplitude parallel to the film normal and its mplications for near-micron thick films are discussed. Consequently, the misfit dislocation sites have nearly no free carrier localization, making the role of these sites on leakage currents highly questionable. Dielectric response of intrinsic thicker films ( &gt; 40 nm) is mostly under the influence of strain relaxation only with minimal interface impact in the limit of ideal electrodes. Our results point out that control of the dislocation density can lead to non-conventional functionalities in ferroelectric thin film capacitors via electromechanical coupling of properties to structure and domain stabilization.
Green manures and plant disease management.
Authors: Larkin R. P. 
Published: November 2013

Abstract

The use of green manures, which involves the incorporation of fresh plant material, has traditionally been primarily for the purpose of soil enrichment through the addition of plant organic matter and nutrients. However, green manures produce many changes in soil physical, chemical and biological properties, and may also result in suppression of specific plant pathogens and diseases. Green manures increase soil microbial biomass and activity, and cause distinct changes in soil microbial populations that may be partially responsible for suppression of diseases. However, green manures of different crops and cultivars may vary considerably in their activity or efficacy against different pathogens and diseases. In particular, green manures of Brassica and related crops have emerged as most effective for management of multiple plant diseases due to their biofumigation potential, which refers to the suppression of pathogens and disease through the release of volatile toxic breakdown products, as well as other unique effects on soil microbial ecology. Brassica crops and other green manures have been used to control a variety of plant pathogens, including species of
Rhizoctonia
,
Verticillium
,
Sderotinia
,
Phythophthora
,
Pythium
,
Aphanomyces
and
Macrophomina
, in various crop production systems, such as for the management of multiple soilborne diseases of potato, including black scurf, common scab and Verticillium wilt. Although disease reduction with green manures can be variable and provides only partial control, it is a versatile and readily-implementable additional management strategy that should be used as an important component within a larger integrated disease management program to provide improved sustainable production systems.
Polyunsaturated fatty acids and fertility in female mammals: an update.
Authors: Wathes D. C. , Cheng ZhangRui Cheng ZhangRui , Marei W. , Fouladi-Nashta A. 
Published: November 2013

Abstract

Both
n
-3 and
n
-6 polyunsaturated fatty acids (PUFAs) are derived from the diet, with concentrations in the reproductive tract reflecting dietary intake. PUFAs have multiple functions: as precursors to eicosanoids, regulators of steroid biosynthesis, inflammatory mediators and supplying energy (particularly in oocytes). The PUFA composition of cell membranes affects signalling pathways and susceptibility to oxidative damage. All of these roles may influence reproduction although results are often inconsistent between studies. Supplementation of cows with various PUFAs can increase the numbers of antral follicles although work on polyovular species (pigs, rodents) has usually failed to detect a change in ovulation rate. The anti-inflammatory actions of
n
-3 PUFAs may reduce follicular PGE production, delaying ovulation and allowing ovulatory follicles to grow larger and produce more steroid. Various PUFA supplements can reduce the interval from calving until first ovulation in cattle although the mechanism is uncertain. Both
n
-3 and
n
-6 PUFA supplements have been fed to various species before collecting oocytes for
in vitro
fertilization. Positive, negative and no effects on subsequent embryo development have all been reported. When PUFAs are added directly to oocyte maturation medium, high doses of linoleic acid (18:2
n
-6) are consistently deleterious, while α-linolenic acid (18:3
n
-3) has been associated with positive outcomes. Uterine prostaglandin production regulates luteal regression and pregnancy recognition. Supplementary
n
-3 PUFAs have either increased or decreased PGF
2α
production in different studies. There is some evidence that cattle and pigs fed a PUFA supplement post insemination may have an increased pregnancy rate.
Potential for producing increased levels of isoflavones in transgenic plants.
Authors: Rasmussen S. , Jones C. 
Published: November 2013

Abstract
Isoflavones are a subgroup of isoflavonoids, a group of flavonoids found almost exclusively in Leguminosae. The main isoflavones accumulating in legumes are daidzein and genistein and 4-0-methylated formononetin and biochanin A. Isoflavones and derived isoflavonoids play important roles in plant protection against pathogens, as signalling molecules in nitrogen fixing legume-rhizobia associations and can be beneficial for human health. Considerable research efforts aim to introduce isoflavones into non-leguminous plants through genetic transformation. The biosynthesis of isoflavones requires the activity of isoflavone synthase (IFS) and transformation of non-leguminous plants with IFS demonstrated that it is, in principle, possible to introduce the biosynthesis of genistein into plants not normally synthesizing this compound. However, isoflavone concentrations are typically at least an order of magnitude lower than those found in soybean seeds or red clover leaves. Major limiting factors are insufficient flux through naringenin, the general precursor of (iso)flavonoids and in particular competition between flavonoid specific enzymes and isoflavonoid specific IFS. Attempts to increase isoflavone concentrations beyond the natural variation in soybean seeds through overexpression of IFS have also been met with limited success and recently identified transcriptional regulators of the isoflavonoid biosynthetic pathway might present a more promising option. All reviewed studies focused on the manipulation of genes encoding proteins directly involved in the (iso)flavonoid pathway and we propose that engineering strategies introducing or enhancing the biosynthesis of isoflavones might have to consider wider metabolic network interactions such as the link of (iso)flavonoid precursors with protein, lipid and carotenoid biosynthetic pathways.
Graded Otx2 activities demonstrate dose-sensitive eye and retina phenotypes
Authors: Bernard Clémence , Kim Hyoung-Tai , Torero Ibad Raoul , Lee Eun Jung , Simonutti Manuel , Picaud Serge , Acampora Dario , Simeone Antonio , Di Nardo Ariel A. , Prochiantz Alain , Moya Kenneth L. , Kim Jin Woo 
Published: November 2013

Abstract
In the human, mutations of OTX2 (Orthodenticle homeobox 2 transcription factor) translate into eye malformations of variable expressivity (even between the two eyes of the same individual) and incomplete penetrance, suggesting the existence of subtle thresholds in OTX2 activity. We have addressed this issue by analyzing retinal structure and function in six mutant mice with graded Otx2 activity: Otx2+/+, Otx2+/AA, Otx2+/GFP, Otx2AA/AA, Otx2AA/GFP and Otx2GFP/GFP. Null mice (Otx2GFP/GFP) fail to develop the head and are embryonic lethal, and compound heterozygous Otx2AA/GFP mice show a truncated head and die at birth. All other genotypes develop until adulthood. We analyzed eye structure and visual physiology in the genotypes that develop until adulthood and report that phenotype severity parallels Otx2 activity. Otx2+/AA are only mildly affected whereas Otx2+/GFP are more affected than Otx2+/AA but less than Otx2AA/AA mice. Otx2AA/AA mice later manifest the most severe defects, with variable expressivity. Electrophysiological and histological analyses of the mouse retina revealed progressive death of bipolar cells and cone photoreceptors that is both Otx2 activity- and age-dependent with the same ranking of phenotypic severity. This study demonstrates the importance of gene dosage in the development of age-dependent pathologies and underscores the fact that small gene dosage differences can cause significant pathological states.
The transgenic expression of LARGE exacerbates the muscle phenotype of dystroglycanopathy mice
Authors: Whitmore Charlotte , Fernandez-Fuente Marta , Booler Helen , Parr Callum , Kavishwar Manoli , Ashraf Attia , Lacey Erica , Kim Jihee , Terry Rebecca , Ackroyd Mark. R. , Wells Kim E. , Muntoni Francesco , Wells Dominic J. , Brown Susan C. 
Published: November 2013

Abstract
Mutations in fukutin-related protein (FKRP) underlie a group of muscular dystrophies associated with the hypoglycosylation of α-dystroglycan (α-DG), a proportion of which show central nervous system involvement. Our original FKRP knock-down mouse (FKRPKD) replicated many of the characteristics seen in patients at the severe end of the dystroglycanopathy spectrum but died perinatally precluding its full phenotyping and use in testing potential therapies. We have now overcome this by crossing FKRPKD mice with those expressing Cre recombinase under the Sox1 promoter. Owing to our original targeting strategy, this has resulted in the restoration of Fkrp levels in the central nervous system but not the muscle, thereby generating a new model (FKRPMD) which develops a progressive muscular dystrophy resembling what is observed in limb girdle muscular dystrophy. Like-acetylglucosaminyltransferase (LARGE) is a bifunctional glycosyltransferase previously shown to hyperglycosylate α-DG. To investigate the therapeutic potential of LARGE up-regulation, we have now crossed the FKRPMD line with one overexpressing LARGE and show that, contrary to expectation, this results in a worsening of the muscle pathology implying that any future strategies based upon LARGE up-regulation require careful management.
LRP4 third β-propeller domain mutations cause novel congenital myasthenia by compromising agrin-mediated MuSK signaling in a position-specific manner
Authors: Ohkawara Bisei , Cabrera-Serrano Macarena , Nakata Tomohiko , Milone Margherita , Asai Nobuyuki , Ito Kenyu , Ito Mikako , Masuda Akio , Ito Yasutomo , Engel Andrew G. , Ohno Kinji 
Published: November 2013

Abstract
Congenital myasthenic syndromes (CMS) are heterogeneous disorders in which the safety margin of neuromuscular transmission is compromised by one or more specific mechanisms. Using Sanger and exome sequencing in a CMS patient, we identified two heteroallelic mutations, p.Glu1233Lys and p.Arg1277His, in LRP4 coding for the postsynaptic low-density lipoprotein receptor-related protein 4. LRP4, expressed on the surface of the postsynaptic membrane of the neuromuscular junction, is a receptor for neurally secreted agrin, and LRP4 bound by agrin activates MuSK. Activated MuSK in concert with Dok-7 stimulates rapsyn to concentrate and anchor AChR on the postsynaptic membrane and interacts with other proteins implicated in the assembly and maintenance of the neuromuscular junction. LRP4 also functions as an inhibitor of Wnt/beta-catenin signaling. The identified mutations in LRP4 are located at the edge of its 3rd beta-propeller domain and decrease binding affinity of LRP4 for both MuSK and agrin. Mutations in the LRP4 3rd beta-propeller domain were previously reported to impair Wnt signaling and cause bone diseases including Cenani–Lenz syndactyly syndrome and sclerosteosis-2. By analyzing naturally occurring and artificially introduced mutations in the LRP4 3rd beta-propeller domain, we show that the edge of the domain regulates the MuSK signaling whereas its central cavity governs Wnt signaling. We conclude that LRP4 is a new CMS disease gene and that the 3rd beta propeller domain of LRP4 mediates the two signaling pathways in a position-specific manner.
The ORC/Cdc6/MCM2-7 complex facilitates MCM2-7 dimerization during prereplicative complex formation
Authors: Evrin Cecile , Fernández-Cid Alejandra , Riera Alberto , Zech Juergen , Clarke Pippa , Herrera M. Carmen , Tognetti Silvia , Lurz Rudi , Speck Christian 
Published: November 2013

AbstractThe replicative mini-chromosome-maintenance 2–7 (MCM2-7) helicase is loaded in Saccharomyces cerevisiae and other eukaryotes as a head-to-head double-hexamer around origin DNA. At first, ORC/Cdc6 recruits with the help of Cdt1 a single MCM2-7 hexamer to form an ‘initial’ ORC/Cdc6/Cdt1/MCM2-7 complex. Then, on ATP hydrolysis and Cdt1 release, the ‘initial’ complex is transformed into an ORC/Cdc6/MCM2-7 (OCM) complex. However, it remains unclear how the OCM is subsequently converted into a MCM2-7 double-hexamer. Through analysis of MCM2-7 hexamer-interface mutants we discovered a complex competent for MCM2-7 dimerization. We demonstrate that these MCM2-7 mutants arrest during prereplicative complex (pre-RC) assembly after OCM formation, but before MCM2-7 double-hexamer assembly. Remarkably, only the OCM complex, but not the ‘initial’ ORC/Cdc6/Cdt1/MCM2-7 complex, is competent for MCM2-7 dimerization. The MCM2-7 dimer, in contrast to the MCM2-7 double-hexamer, interacts with ORC/Cdc6 and is salt-sensitive, classifying the arrested complex as a helicase-loading intermediate. Accordingly, we found that overexpression of the mutants cause cell-cycle arrest and dominant lethality. Our work identifies the OCM complex as competent for MCM2-7 dimerization, reveals MCM2-7 dimerization as a limiting step during pre-RC formation and defines critical mechanisms that explain how origins are licensed.
Fitness traits and underlying genetic variation related to host plant specialization in the aphid Sitobion avenae
Authors: Gao Su‐Xia , Liu De‐Guang , Chen Hui , Meng Xiu‐Xiang 
Published: November 2013

AbstractSitobion avenae (F.) is an important cereal pest worldwide that can survive on various plants in the Poaceae, but divergent selection on different host plants should promote the evolution of specialized genotypes or host races. In order to evaluate their resource use strategies, clones of S. avenae were collected from oat and barley. Host‐transfer experiments for these clones were conducted in the laboratory to compare their fitness traits. Our results demonstrated that barley clones had significantly lower fecundity and tended to have longer developmental times when transferred from barley to oat. However, oat clones developed faster after they were transferred to barley. Clones from oat and barley had diverged to a certain extent in terms of fecundity and developmental time of the nymphs. The separation of barley clones and oat clones of S. avenae was also evident in a principal component analysis. Barley clones tended to have higher broad‐sense heritabilities for fitness traits than oat clones, indicating the genetic basis of differentiation between them. Barley clones showed significantly higher extent of specialization compared to oat clones from two measures of specialization (i.e., Xsp and Ysp). Therefore, barley clones were specialized to a certain extent, but oat clones appeared to be generalized. The fitness of S. avenae clones tended to increase with higher extent of specialization. The evolution toward ecological specialization in S. avenae clones, as well as the underlying genetic basis, was discussed.
Uncommon presentations of primary systemic necrotizing vasculitides: the Great Masquerades
Authors: Sharma Aman , Gopalakrishan Dharmesh , Nada Ritambhra , Kumar Susheel , Dogra Sunil , Aggarwal Mayank M. , Gupta Rajesh , Minz Ranjana W. , Kakkar Nandita , Vashishtha Rakesh K. , Singh Surjit 
Published: November 2013

AbstractIntroductionSystemic vasculitides are great masqueraders and at times their presenting manifestations can be very different from the usual recognized patterns. Such uncommon presentations of granulomatosis with polyangiitis (Wegener's granulomatosis), classical polyarteritis nodosa and unclassifiable vasculitides are described here with the relevant review of literature.MethodsAll patients diagnosed as having systemic vasculitides and classified as having granulomatosis with polyangiitis (Wegener's granulomatosis), classic polyarteritis nodosa, microscopic polyangiitis and unclassifiable vasculitis according to EMEA consensus methodology and followed up prospectively from June 2007 to December, 2011 were included. Details of uncommon presentations of these disorders were identified.ResultsSeventy‐nine patients with systemic vasculitides were seen under our rheumatology services during this period. These included 45 patients with granulomatosis with polyangiitis (Wegener's granulomatosis), 18 with classic polyarteritis nodosa, five with microscopic polyangiitis, four with Churg–Strauss syndrome and seven with unclassifiable vasculitis. The uncommon presentations of granulomatosis with polyangiitis were a tumefactive subcutaneous mass in the thigh; prostatomegaly with obstructive uropathy and advanced renal failure; and predominant gastrointestinal (GI) vasculitis with thrombocytopenia and coagulopathy at presentation. The uncommon manifestations of classic polyarteritis nodosa were secondary antiphospholipid antibody syndrome and Budd–Chiari syndrome. One patient with massive lower GI bleeding required surgical resection of the large bowel which showed isolated necrotizing granulomatous GI vasculitis. Single organ vasculitis of the GI tract was diagnosed.ConclusionsSystemic necrotizing vasculitides may present with uncommon manifestations and a high index of suspicion is required for early diagnosis and prompt treatment to prevent adverse outcomes.
The Nordic medical birth registers – a potential goldmine for clinical research
Authors: Langhoff‐Roos Jens , Krebs Lone , Klungsøyr Kari , Bjarnadottir Ragnheidur I. , Källén Karin , Tapper Anna‐Maija , Jakobsson Maija , Børdahl Per E. , Lindqvist Pelle G. , Gottvall Karin , Colmorn Lotte Berdiin , Gissler Mika 
Published: November 2013

AbstractThe Nordic medical birth registers have long been used for valuable clinical research. Their collection of data for more than four decades offers unusual possibilities for research across generations. At the same time, serum and blotting paper blood samples have been stored from most neonates. Two large cohorts (approximately 100 000 births) in Denmark and Norway have been described by questionnaires, interviews and collection of biological samples (blood, urine and milk teeth), as well as a systematic prospective follow‐up of the offspring. National patient registers provide information on preceding, underlying and present health problems of the parents and their offspring. Researchers may, with permission from the national authorities, obtain access to individualized or anonymized data from the registers and tissue‐banks. These data allow for multivariate analyses but their usefulness depends on knowledge of the specific registers and biological sample banks and on proper validation of the registers.
Hypothermic Machine Perfusion Versus Cold Storage in the Rescuing of Livers From Non‐Heart‐Beating Donor Rats
Authors: Carnevale Matías E. , Balaban Cecilia L. , Guibert Edgardo E. , Bottai Hebe , Rodriguez Joaquin V. 
Published: November 2013

AbstractThe aim of this work was to compare the efficiency of cold storage (CS) and hypothermic machine perfusion (HMP) methods of preserving grafts excised from non‐heart‐beating donors that had suffered 45 minutes of warm ischemia. We developed a new solution for HMP to use in liver transplantation, based on BES, gluconate, and polyethylene glycol (BGP‐HMP solution). After 24 h of HMP or CS, livers were reperfused at 37°C with Krebs–Henseleit solution with added dextran. For both procedures, portal pressure and flow were measured and the intrahepatic resistance (IR) was calculated. The pH oscillations and enzyme activities (LDH, AST, and ALT) were evaluated for the perfusion buffer during normothermic reperfusion. O2 consumption of the liver, glycogen production, and bile flow were also measured during the normothermic reperfusion period. Portal flow and IR showed statistical differences (P < 0.05) between the two groups (n = 5). HMP with BGP‐HMP solution resulted in higher values of portal flow and lower IR than CS with HTK solution. Enzyme release after 90 min of reperfusion did not show statistical differences between groups. With regard to bile flow and O2 consumption, livers preserved by both processes were able to produce bile, but livers preserved with HMP were able to take up more O2 than livers preserved by CS.
Late Adverse Events after Enhanced and Unenhanced MRI and CT: A Prospective Study
Authors: Azzouz Manal , Rømsing Janne , Thomsen Henrik S. 
Published: November 2013

AbstractProspective evaluation of frequency of late and very late adverse events in patients undergoing enhanced or unenhanced magnetic resonance imaging (MRI) or computed tomography (CT). The imaging procedure was performed according to the protocols of the department. All patients were contacted 3 days after their imaging procedure for the occurrence of late adverse events (LAEs) and a month later for the occurrence of very late adverse events (VLAEs) using a structured questionnaire. A total of 1042 (71%) among 1473 patients completed both the 3‐day and 1‐month questionnaire. The incidence of LAEs was significantly higher in the enhanced MRI (38%) and CT (27%) groups than unenhanced MRI (20%) and CT (16%) groups. The frequency of nausea, dizziness, abdominal pain and diarrhoea was significantly higher in the enhanced MRI group than in the MRI control group, while taste sensation was reported more frequent in the enhanced CT group than in the CT control group. The incidence of VLAEs was significantly higher in the enhanced CT (21%) than unenhanced CT group (13%). The same LAEs and VLAEs were reported in all four groups. LAEs and VLAEs were reported more often in patients with allergy in both the enhanced and unenhanced groups. The incidence of LAEs and VLAEs was higher in the enhanced groups than in the unenhanced groups. The most reported adverse events in the enhanced groups were also reported in the unenhanced groups. Patients with allergy reported LAE and VLAE more often. This suggests that adverse events may not always be caused by the contrast media.