bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanisms of resistance to the brown planthopper Nilaparvata lugens in wild rice (Oryza spp.) cultivars
Authors: Velusamy R. , Kumar M. Ganesh , Thangaraj Edward Y. S. Johnson
Published: April 2011

Three wild rice species and six cultivated rice varieties were evaluated to determine their mechanisms of resistance to Nilaparvata lugens (Stal.). Wild rice species, Oryza officinalis, O. punctata, and O. latifolia and cultivated rices Rathu Heenati (Bph 3), Babawee (bph 4), ARC 10550 (bph 5), Swarnalata (Bph 6), Ptb 33 (bph 2 + Bph 3) and the susceptible Taichung Native (TN 1) (no resistance gene) were included in the study. In a free choice seedbox screening test, wild rice species maintained their high level of resistance through the 48 h exposure to N. lugens nymphs while plant damage ratings of cultivated rice varieties increased with time. Wild rices were non preferred and significantly more individuals settled on susceptible TN 1 followed by cultivated rices. The quantity of food ingested and assimilated by N. lugens on wild rices was less than on cultivated resistant varieties. N. lugens caged on resistant wild rices had slow nymphal development, reduced longevity, low fecundity, and low egg hatchability as compared to N. lugens on cultivated resistant varieties.
Analysis of wheat resistance to the cereal aphidSitobion avenaeusing electrical penetration graphs and flow charts combined with correspondence analysis
Authors: Caillaud Claudia M. , Pierre J. S. , Chaubet B. , Di Pietro J. P.
Published: April 2011

The behaviour ofSitobion avenae(F.) was compared on resistant wheat lines ofTriticum monococcum(L.) and a susceptible variety ofTriticum aestivum(L.). Firstly, stylet penetration activities were monitored with the Electrical Penetration Graph (EPG) technique and subsequently analysed using flow charts combined with correspondence analysis. Plant resistance was shown to be associated with repeated penetrations without access to either the xylem or the phloem, and with numerous failures in starting a sustained sap ingestion (as represented by pattern E2). Access to sieve elements of the phloem did not seem to be much affected on resistant plants but it took the aphid three times as long to produce a sap ingestion pattern when maintained on the resistant lineT. monococcumn ° 44 (Tm44) as compared with aphids maintained on susceptible plants. As a result the total time spent in ingesting from sieve elements was reduced by 72% on Tm44. Secondly, direct observations of freely‐moving apterous adults were performed. Aphids did not discriminate between resistant and susceptible wheat during the first 30 min of access to test leaves, but only 4 out of 25 aphids were still probing after eight hours on resistant Tm44.

The relevance of these results to possible location of the resistance factor(s) are discussed. Although detection of plant resistance before sieve elements are reached can not be rigorously excluded, the factors involved inT. monococcumresistance toS. avenaeundoubtedly occur within the phloem vessels.
Seasonal abundance and spatial patterns of the predator Lyctocoris campestris in stored corn*
Authors: Parajulee Megha N. , Phillips Thomas W.
Published: April 2011

A two‐year sampling study (1992–93) in a flat storage of shelled corn showed that the larger pirate bug, Lyctocoris campestris (F.) (Heteroptera: Anthocoridae), can be detected by relative sampling techniques as early as the second week of May. The perceived seasonal pattern of L. campestris varied with trapping method. Of the three relative sampling methods used, probe traps consistently captured more bugs of both sexes than cardboard traps in the grain and sticky flight traps. Probe traps showed a third degree polynomial trend through the season. On the other hand, flight traps were effective for monitoring L. campestris population during early and mid‐summer when temperatures were high, but the effectiveness declined during late summer and early fall. Cardboard traps showed the opposite trend to those of flight traps, with increasing L. campestris abundance during the fall when bugs sought refuge as temperature decreased. Sampling date and environmental factors, including grain moisture content, air and grain temperatures were correlated with trap capture. Earlier work reported that L. campestris showed a highly female biased sex ratio in the field as opposed to a 1:1 sex ratio in laboratory colonies. The present study found that the estimate of sex ratios in the field can differ with trapping methods. Of the three relative sampling methods used, flight and cardboard traps, in most cases, showed no deviation from a 1:1 sex ratio. Probe traps, however, indicated a highly female biased sex ratio in field populations. Absolute sampling using a 1140 ml cup sampler also showed no deviation from a 1:1 sex ratio in the field population. The data suggested that relative sampling methods may be inappropriate for sex ratio estimation in the field. Thus, an absolute sampling method is required for determination of the true field sex ratio of L. campestris. Analyses of dispersion patterns showed that both males and females of L. campestris exhibit an aggregated spatial distribution in the grain.
Variations in body length, weight, fat content and survival in Coccinella septempunctata at different hibernation sites
Authors: Zhou X. , Honek A. , Powell W. , Carter N.
Published: April 2011

Adults of Coccinella septempunctata L. (Coleoptera; Coccinellidae) were sampled in four overwintering sites: one in England and three at different altitudes in the Czech Republic (350–1420 m above sea level) in autumn 1992 and spring 1993. Body length, dry weight and fat weight were measured. There were significant differences in body length between sampling sites in spring 1993, but not in autumn 1992. The average sex ratio (♀) in all samples was 1:0.60 in 1992 and 1:0.72 in 1993. Females were significantly larger and heavier, and contained more fat than males in both sampling periods. Dry weight and fat weight were positively correlated to body length at all sampling sites except at Ruzyne, in the Czech Republic. Adults hibernating at higher altitudes and away from their breeding and feeding habitats had significantly more fat than those hibernating at lower altitudes. Fat reserves were reduced by 30% during the hibernation at the top of the Krkonose mountain, in the Czech Republic, where temperatures were much lower, but more than half of the fat reserves were consumed during the overwintering period at the other sampling sites. The significance of body length and fat reserves in relation to adult hibernation sites and overwintering survival is discussed.
Elimination of sexual brood in the Argentine ant Linepithema humile: queen effect and brood recognition
Authors: Passera L. , Aron S. , Bach D.
Published: April 2011

Mated queens of the ant Linepithema humile (Iridomyrmex humilis Mayr) introduced into dequeened colony fragments rearing sexual brood elicited worker aggression resulting in queen larvae being bitten and eliminated. By contrast, male larvae were spared. Regarding queen brood, killing mainly concerned small and medium sized larvae. A large proportion of the large larvae escaped extermination, and prepupae and pupae were spared. These data suggest that workers were able to discriminate sex, caste and age of the brood.

That a queen pheromone may be involved was shown by experiments using whole or cut corpses that were either rinsed or not rinsed in pentane. The pheromone eliciting worker aggressive behaviour was shown to act over a short distance, suggesting that it is somewhat volatile. Similarities and differences between this new queen pheromone and other known queen pheromones acting on queen production or worker attraction are discussed as well as the origin of the signals underlying the recognition of the larval classes.
Observation of epigeic predators and predation on artificial prey in a cereal field
Authors: Lys Jon‐Andri
Published: April 2011

Predation activity of different epigeic predators on artificially supplied prey was studied in a cereal field during several 24 h periods from spring to early summer 1993. Carabids were the most frequently observed predators. Among them Poecilus cupreus was the most voracious species during day‐time, and Agonum muelleri during night‐time. Predation rates were highest between 10.00 and 18.00 h and lowest between 02.00 and 10.00 h. Linear regressions showed significantly positive relations between temperature and predation rates, and between predation and activity density of epigeic predators. The latter relation was stronger when only activity density of predators which were observed to consume baits was included. Quadrat sampling and pitfall sampling showed that with the former only a small proportion of bait‐consuming predators were caught whereas with the latter method this proportion was high.
Oviposition and feeding preferences of a flower‐feeding weevil, Coelocephalapion aculeatum, in relation to conspecific damage to its host‐plant
Authors: Heard Timothy A.
Published: April 2011

The oviposition and feeding preferences of Coelocephalapion aculeatum Fall (Coleoptera: Apionidae), a host specific florivore of Mimosa pigra L. (Mimosaceae), were studied in relation to conspecific damage to its host‐plant. Adults of C. aculeatum cease ovipositing in inflorescences when the egg load reaches a number consistent with the larval carrying capacity of the inflorescence. The basis for this oviposition deterrence was examined by offering inflorescences damaged by adult feeding alone, larval feeding alone and a combination of adult feeding and oviposition. Adults preferred to oviposit on inflorescences which are not damaged by either adult feeding, larval feeding, or oviposition. No evidence for the existence of an oviposition deterring pheromone (ODP) was found. I suggest that the ability of a single host inflorescence to support the development of many larvae causes selection for the use of these oviposition deterring cues which can convey more quantitative information about the level of previous infestation than can ODPs. Adults fed a similar amount on damaged compared to undamaged inflorescences. These results assisted in the design of host range testing trials and allows predictions to be made about the effectiveness of this insect as a biological control agent.
Laboratory rearing of the squirrel flea Ceratophyllus sciurorum sciurorum with notes on its biology
Authors: Larsen K. S.
Published: April 2011

A rearing method for the flea Ceratophyllus (Monopsyllus) sciurorum sciurorum, a pest on farmed mink in Europe, has been developed. The behaviour of egg‐laying and the development period are described at 23 °C and 80% r.h. The eggs of C. sciurorum sciurorum hatched after 4–7 days and cocoons were formed 10–12 days later. The development period from egg to newly emerged adult was 23–32 days. Females emerged, in general, earlier than males.
Does host range influence susceptibility of herbivorous insects to non‐host plant proteinase inhibitors?
Authors: Broadway Roxanne M. , Villani Michael G.
Published: April 2011

We examined the influence of proteinase inhibitors on digestive enzymes and development of oriental beetle, Exomala orientalis Waterhouse, European chafer, Rhizotrogus majalis (Razoumowsky), Phyllophaga white grub, Phyllophaga anxia (LeConte), cranberry root grub, Lichnanthe vulpina (Hentz), Japanese beetle, Popillia japonica Newman, Asiatic garden beetle, Maladera castanea (Arrow) (Coleoptera: Scarabaeidae), and the black cutworm, Agrotis ipsilon (Rottemburg) (Lepidoptera: Noctuidae). We demonstrated that all species within our test group had alkaline midguts that contained proteinase activity that could be inhibited, in vitro with serine proteinase inhibitors. Our data suggests that host range may influence the susceptibility to non‐host inhibitors. Chronic ingestion of the serine proteinase inhibitor, Kunitz‐soybean trypsin inhibitor (STI), significantly reduced proteolytic activity in vivo in those species with relatively specialized feeding habits (i.e., cranberry root grub, Japanese beetle, Asiatic garden beetle, and black cutworm). Chronic ingestion of STI also resulted in reduced larval growth and delayed pupation for black cutworm, and elevated larval mortality for Japanese beetle. However, chronic ingestion of STI did not influence larval survival for those species with relatively generalized feeding habits (i.e., oriental beetle, European chafer). Based on these results, we propose mechanistically‐based criteria for selecting proteinase inhibitors for phytochemical defense against herbivorous insects.
Inheritance of dicrotophos resistance in greenhouse whitefly
Authors: Omer Amir D. , Tabashnik Bruce E. , Johnson Marshall W.
Published: April 2011

We studied inheritance of resistance to dicrotophos in greenhouse whitefly, Trialeurodes vaporariorum Westwood (Homoptera, Aleyrodidae). Compared with females from a field‐collected susceptible strains (S), females from a resistant strain (R) of T. vaporariorum derived from heavily treated cotton fields had a 28‐fold greater LC50 to dicrotophos in laboratory bioassays. Concentration‐mortality lines obtained from female progeny of reciprocal F1 crosses (R♀ XS♂ and S♀ XR♂) were similar, suggesting that inheritance of dicrotophos resistance was autosomal and not influenced by maternal effects. Responses of F1 female progeny were similar to those of the parental S strain, indicating that the resistance was partially recessive (degree of dominance, D, was −0.61). Mortality observed in female progeny obtained from a backcross (F1♀ XR♂) corresponded more closely to expectations derived from polygenic models than to expectations from a monogenic model. The estimated number of effective factors (sensu Lande, 1981) contributing equally to resistance was three.
Pupation site and emergence time influence the mating success of bagworm females, Oiketicus kirbyi
Authors: Rhainds Marc , Gries Gerhard , Chinchilla Carlos
Published: April 2011

In commercial oil palm plantations in Costa Rica, we tested the hypotheses that pupation site and emergence time affect the mating success of protogynous female bagworms, Oiketicus kirbyi (Guilding) (Lepidoptera: Psychidae). Greater proportions of female than male pupae on upper leaves of oil palms and greater proportions of mated females in the upper rather than lower crown strata support the hypothesis that selection of pupation site by female larvae influences the mating success of adults. Increasing captures of males with increasing trap height further suggest that enhanced mating success of females in tree tops may be attributed either to most effective dissemination of sex pheromone on higher sites, or to males foraging predominantly in the upper strata of oil palms. As the majority of females pupated in the middle rather than upper crown of oil palms, selection of pupation site by females may be affected by additional as yet unknown factors. Emergence of females significantly preceded emergence of males. Increasing proportions of mated females throughout the emergence season probably resulted from an increased ‘availability’ of males. In tropical rainforests with local variations in O. kirbyi developmental time and stage, protogyny may represent an evolutionary strategy that furthers outbreeding.
The effect of stem and cob borers on maize subjected to different nitrogen treatments
Authors: Sétamou M. , Schulthess F. , Bosque‐Pérez N. A. , Thomas‐Odjo A.
Published: April 2011

The influence of four nitrogen levels (0, 60, 90 and 120 kg N/ha) on growth of maize and development of lepidopterous pests was investigated in a field trial. Nitrogen had a positive effect on both plant growth variables (plant height, stem diameter and yield), and development and survival of Sesamia calamistis and Eldana saccharina, and thereby increased the incidence of dead hearts and stem tunneling. However, the percent yield loss due to artificial infestation decreased with increasing N application rate from 20% to 11% in the in the 0kg/ha and 120kg/ha treatment, respectively. Using a multiple regression analysis, plant height, plant diameter and stem tunneling were found to be the most important variables explaining the variability in maize yield.
Influence of wind conditions and intertrap spacing on pheromone trap catches of male European pine sawfly, Neodiprion sertifer
Authors: Wedding Rolf , Anderbrant Olle , Jönsson Peter
Published: April 2011

The spatial distribution of catches of male European pine sawfly, Neodiprion sertifer (Geoffr.) (Hymenoptera, Diprionidae), was studied using different pheromone trap arrays. In hexagonal trap groups, trap interference was evident by reduced catch in the central of seven traps spaced 10 to 40 m apart. When the trap spacings were either 5 or 80 m no significant reduction could be shown. The interaction was more pronounced for strong (100 μg) pheromone ([2S, 3S, 7S]‐3, 7‐dimethyl‐2‐pentadecanyl acetate) lures than for weak ones (10 μg). Similarly, the inner traps caught less than the outer traps in grids of 6 × 6 traps spaced 20 or 50 m apart. Mark‐release‐recapture experiments in the grid array confirmed that a majority of the males originated from outside the trap group and were caught in the first trap they encountered. There were no differences between catches in downwind, crosswind and upwind traps. Thus, no ‘overshooting’ was evident during average conditions, i.e. the sawflies did not divert from the trap initially attracting them by flying to the upwind trap. However, the proportion caught in the upwind traps increased with increasing wind velocity, suggesting more overlapping pheromone plumes at higher wind speeds. Also, the recapture rate of released males increased with increasing wind velocity up to a daily average of 3.1 m/s at 2 m, indicating that sawflies more easily find the pheromone source, probably due to a more stable pheromone puff trajectory during higher wind velocities. The application of pheromone traps in e.g. monitoring studies is discussed and a distance of at least 50 m between the traps with strong lures used in the present study is recommended to avoid trap interaction.
Common Molecular Cytogenetic Pathway in Papillary Tumors of the Pineal Region (PTPR)
Authors: Gutenberg Angelika , Brandis Almuth , Hong Bujung , Gunawan Bastian , Enders Christina , Schaefer Inga‐Marie , Burger Ralf , Ostertag Helmut , Gaab Michael , Krauss Joachim K. , Füzesi Laszlo
Published: April 2011

Primary papillary tumors of the central nervous system and particularly the pineal region are rare. Papillary tumor of the pineal region (PTPR) is a recently described neoplasm that has been formally recognized in the 2007 World Health Organization Classification of Tumors of the Nervous System. Because of their rarity, further pheno‐ and genotypical observations as well as therapeutic experience are necessary to differentiate PTPR from other primary or secondary papillary tumors of this region. We herein present three cases of PTPR characterized by local recurrence in two of them. Primary and recurrent tumors were analyzed by immunohistochemistry and comparative genomic hybridization (CGH). From our results clonal chromosomal aberrations can be postulated which seem to be a feasible tool to differentiate PTPRs from other primary or secondary papillary tumors of this region.
Hypertension Complicating Diabetic Pregnancies: Pathophysiology, Management, and Controversies
Authors: Sullivan Shannon D. , Umans Jason G. , Ratner Robert
Published: April 2011

Hypertensive disorders of pregnancy (HDP), including pre‐existing hypertension, gestational hypertension, and preeclampsia, further complicate already high‐risk pregnancies in women with diabetes mellitus (DM). Women with both pre‐existing and gestational diabetes are at increased risk for HDP, leading to higher maternal and fetal morbidity. Further, particularly in diabetic women and women with a history of gestational diabetes, HDP significantly increases the risk for future cardiovascular events. For clinicians, women with hypertension and diabetes during pregnancy pose a management challenge. Specifically, preconception management should stress strict control of glycemia, blood pressure, and prevention of diabetic complications, specifically nephropathy, which specifically increases the risk for preeclampsia. During gestation, clinicians must be aware of potential maternal and fetal complications associated with various anti‐hypertensive therapies, including known fetotoxicity of ACE inhibitors and ARBs when given in the 2nd or 3rd trimester, and the risks and benefits of expectant management versus delivery in cases of severe gestational hypertension or preeclampsia. Indeed, diabetic women must be followed closely prior to conception and throughout gestation to minimize the risk of HDP and its associated complications. J Clin Hypertens (Greenwich). 2011;13:275–284. © 2011 Wiley Periodicals, Inc.
Pollen and chromosome studies in Hieracium sect. Alpestria (Asteraceae)
Authors: Thomas S. , Bailey J. P. , Rich T. C. G.
Published: April 2011

Potential pollen viability has been investigated in British apomictic Hieracium section Alpestria and related species using Alexander's Stain. New and existing chromosome counts are given. Some species produced no pollen, others varied in the amount they produced, and a few species consistently produced reasonable quantities. The three triploid section Alpestria species produced very little or no pollen, whilst the amount produced by the tetraploids varied widely. Section Alpestria species had significantly lower pollen viability than the non‐section Alpestria species. The generally low pollen production in most species of section Alpestria is consistent with them being of hybrid origin.
On the continuity of Arthur’s trace formula: the semisimple terms
Authors: Finis Tobias , Lapid Erez
Published: April 2011

We show that the semisimple part of the trace formula converges for a wide class of test functions.
Seven-Sensor Fast-Response Probe for Full-Scale Wind Turbine Flowfield Measurements
Authors: Mansour M. , Kocer G. , Lenherr C. , Chokani N. , Abhari R. S.
Published: April 2011

The unsteady wind profile in the atmospheric boundary layer upstream of a modern wind turbine is measured. The measurements are accomplished using a novel measurement approach that is comprised of an autonomous uninhabited aerial vehicle (UAV) that is equipped with a seven-sensor fast-response aerodynamic probe (F7S-UAV). The autonomous UAV enables high spatial resolution (∼6.3% of rotor diameter) measurements, which hitherto have not been accomplished around full-scale wind turbines. The F7S-UAV probe developed at ETH Zurich is the key-enabling technology for the measurements. The time-averaged wind profile from the F7S-UAV probe is found to be in very good agreement to an independently measured profile using the UAV. This time-averaged profile, which is measured in moderately complex terrain, differs by as much as 30% from the wind profile that is extrapolated from a logarithmic height formula; therefore, the limited utility of extrapolated profiles, which are commonly used in site assessments, is made evident. The time-varying wind profiles show that at a given height, the velocity fluctuations can be as much as 44% of the time-averaged velocity, therefore indicating that there are substantial loads that may impact the fatigue life of the wind turbine’s components. Furthermore, the shear in the velocity profile also subjects the fixed pitch blade to varying incidences and loading. Analysis of the associated velocity triangles indicates that the sectional lift coefficient at midspan of this modern turbine would vary by 12% in the measured time-averaged wind profile. These variations must be accounted in the structural design of the blades. Thus, the measurements of the unsteady wind profile accomplished with this novel measurement system demonstrate that it is a cost effective complement to the suite of available site assessment measurement tools.
OPTOELECTRONIC PROPERTIES OF ZnO NANOPARTICLES DEPOSITION ON POROUS SILICON
Authors: KHASHAN KHAWLA S.
Published: April 2011

In this work, a colloid of nanocrystalline ZnO particles was prepared by chemical method, and sprayed on porous silicon (PS) substrate which was prepared by electrochemical etching under a current density of 15 mA/cm2 for 10 min. The initial radius of the ZnO particles was found to be (2.2 nm). FTIR spectra exhibit the presence of Zn – O bond which indicates the formation of ZnO particles. Also spectra reveals the formation of SiH x(x = 1–2) and Si – O bond which indicates the presence of porous layer. High-performance rectification was obtained, with high photoresponsivity of 0.54 A/W at 400 nm. The corresponding quantum efficiency was 166.7%. The results show that ZnO on PS structures act as good candidates for making highly efficient photodiodes.
VIRIAL THEOREM AND NON-EQUILIBRIUM CANONICAL-DISSIPATIVE DISTRIBUTIONS CHARACTERIZING PARKINSON TREMOR
Authors: Frank T. D.
Published: April 2011

The virial theorem and the concept of canonical-statistical distributions represent two fundamental elements of statistical physics. We apply these concepts to hand tremor oscillations recorded from six Parkinson patients. We find that the virial theorem holds for Parkinson tremor oscillations. In contrast, we find that the concept of canonical distributions fails to a certain extent and needs to be replaced by the notion of non-canonical (i.e., canonical-dissipative) distributions. In doing so, our analysis reveals both general statistical aspects and non-equilibrium aspects of Parkinson hand tremor.
CONTROL OF THE CASIMIR FORCE USING SEMICONDUCTOR TEST BODIES
Authors: KLIMCHITSKAYA G. L. , MOHIDEEN U. , MOSTEPANENKO V. M.
Published: April 2011

We describe experimental and related theoretical work on the measurement of the Casimir force using semiconductor test bodies. This field of research started in 2005 and several important and interesting results have already been obtained. Specifically, the Casimir force or its gradient was measured in the configuration of an Au -coated sphere and different semiconductor surfaces. It was found that the force magnitude depends significantly on the replacement of the metal with a semiconductor and on the concentration of charge carriers in the semiconductor material. Special attention is paid to the experiment on the optical modulation of the Casimir force. In this experiment the difference in Casimir force between an Au -coated sphere and a Si plate in the presence and in the absence of laser light was measured. Possible applications of this experiment are discussed, specifically, for the realization of the pulsating Casimir force in three-layer systems. Theoretical problems arising from the comparison of the experimental data for the difference in Casimir force with the Lifshitz theory are analyzed. We consider the possibility to control the magnitude of the Casimir force in phase transitions of semiconductor materials. Experiments on measuring the Casimir force gradient between an Au -coated sphere and a Si plate covered with rectangular corrugations of different characters are also described. Here, we discuss the interplay between the material properties and nontrivial geometry and the applicability of the proximity force approximation. The review contains comparison between different experiments and analysis of their advantages and disadvantages.
STRUCTURAL AND OPTICAL PROPERTIES OF PLASMA-POLYMERIZED 1-BENZYL-2-METHYLIMIDAZOLE THIN FILMS
Authors: SARKER RAMA BIJOY , BHUIYAN A. H.
Published: April 2011

Plasma-polymerized 1-benzyl-2-methylimidazole (PPBMI) thin films have been deposited onto glass substrates by glow discharge technique. Scanning electron micrographs reveal that the surface morphology of PPBMI thin films is uniform and flawless. Fourier transform infrared spectroscopy analysis shows that the chemical composition of PPBMI films is different from that of the BMI. From the ultraviolet-visible spectra direct and indirect transition energy gaps were determined to be between 3.10 and 3.35 eV and 1.80 and 1.95 eV, respectively, for as-deposited PPBMI thin films of different thicknesses. Both direct and indirect transition energy gaps increase with increasing thickness and decrease upon heat treatment.
EFFECT OF GRAIN BOUNDARY ON THE CHARACTERISTICS OF POLY-SiMETAL–INSULATOR–SEMICONDUCTOR PHOTODETECTOR
Authors: ZHOU YUMING , HE YIGANG
Published: April 2011

The effect of grain boundary on the characteristics of poly- Si metal–insulator–semiconductor photodetector is investigated utilizing two-dimensional device simulator. In the investigation, the trap states in grain boundary are composed of two types: tail states and deep-level states, both of which consist of acceptor-like trap and donor-like trap. The simulation results show that the photocurrent of photodetector decreases considerably in the case of tail states above 5 ×19 cm-3, but less susceptible to deep-level states. Furthermore, it is found that the spectral responsivities of the photodetector decrease when the energy level of acceptor-like traps shifts towards the midgap, but keep unchanged for the case of donor-like traps.
MULTILINEAR EQUATIONS IN AMALGAMS OF FINITE INVERSE SEMIGROUPS
Authors: CHERUBINI A. , NUCCIO C. , RODARO E.
Published: April 2011

Let S = S1 *U S2 = Inv〈X; R〉 be the free amalgamated product of the finite inverse semigroups S1, S2 and let Ξ be a finite set of unknowns. We consider the satisfiability problem for multilinear equations over S, i.e. equations wL ≡ wR with wL, wR ∈ (X ∪ X-1 ∪ Ξ ∪ Ξ-1)+ such that each x ∈ Ξ labels at most one edge in the Schützenberger automaton of either wL or wR relative to the presentation 〈X ∪ Ξ|R〉. We prove that the satisfiability problem for such equations is decidable using a normal form of the words wL, wR and the fact that the language recognized by the Schützenberger automaton of any word in (X ∪ X-1)+) relative to the presentation 〈X|R〉 is context-free.
AUTOMATA OVER A BINARY ALPHABET GENERATING FREE GROUPS OF EVEN RANK
Authors: STEINBERG BENJAMIN , VOROBETS MARIYA , VOROBETS YAROSLAV
Published: April 2011

We construct automata over a binary alphabet with 2n states, n ≥ 2, whose states freely generate a free group of rank 2n. Combined with previous work, this shows that a free group of every finite rank can be generated by finite automata over a binary alphabet. We also construct free products of cyclic groups of order two via such automata.
FINITE SELF-SIMILAR p-GROUPS WITH ABELIAN FIRST LEVEL STABILIZERS
Authors: ŠUNIĆ ZORAN
Published: April 2011

We determine all finite p-groups that admit a faithful, self-similar action on the p-ary rooted tree such that the first level stabilizer is abelian. A group is in this class if and only if it is a split extension of an elementary abelian p-group by a cyclic group of order p.

The proof is based on use of virtual endomorphisms. In this context the result says that if G is a finite p-group with abelian subgroup H of index p, then there exists a virtual endomorphism of G with trivial core and domain H if and only if G is a split extension of H and H is an elementary abelian p-group.
A TAXONOMY OF INNOVATION: CONFIGURATIONS OF ATTRIBUTES IN HEALTHCARE INNOVATIONS
Authors: ADAMS RICHARD , TRANFIELD DAVID , DENYER DAVID
Published: April 2011

In spite of the continued importance of an innovation's attributes to research methodologies, and the increasing tendency toward multidimensional conceptualizations, the lack of a theoretically derived and empirically developed classification of innovations, conceived in terms of these perceived characteristics, continues to deter substantive research in the area. The absence of a stable descriptive framework has constrained researchers' facility to develop cross-case and cumulative research. In this paper, in which innovations are conceptualized as complex and multi-dimensional, we report on a mixed-method, exploratory study addressing the question of innovation classification. Data from a rigorous thematic investigation of the literature and four case studies, are synthesized into a descriptive framework incorporating 13 variables (innovation attributes). Following operationalization of the framework, we conduct a cluster analysis of the returns from a post-adoption survey of 310 innovations. Three distinct innovation types are identified: readily-adopted, challenging and under-cover. The attributes disruption, observability, profile and risk were found to be particularly important in distinguishing clusters that offer opportunities for new theoretical development. The UK National Health Service (NHS) forms the context for the study. Implications for theory and practice are examined.
Dimension-reducible Boolean functions based on affine spaces
Authors: Bernasconi Anna , Ciriani Valentina
Published: April 2011

We define and study a new class of regular Boolean functions called D-reducible. A D-reducible function, depending on all its
n
input variables, can be studied and synthesized in a space of dimension strictly smaller than
n
. We show that the D-reducibility property can be efficiently tested, in time polynomial in the representation of
f
, that is, an initial SOP form of
f
. A D-reducible function can be efficiently decomposed, giving rise to a new logic form, that we have called DredSOP. This form is shown here to be generally smaller than the corresponding minimum SOP form. Our experiments have also shown that a great number of functions of practical importance are indeed D-reducible, thus validating the overall interest of our approach.
Ubiquitin-specific protease 2-45 (Usp2-45) binds to epithelial Na+ channel (ENaC)-ubiquitylating enzyme Nedd4-2
Authors: Oberfeld Benjamin , Ruffieux-Daidié Dorothée , Vitagliano Jean-Jacques , Pos Klaas Martinus , Verrey François , Staub Olivier
Published: April 2011

Regulation of the epithelial Na+ channel (ENaC) by ubiquitylation is controlled by the activity of two counteracting enzymes, the E3 ubiquitin-protein ligase Nedd4-2 (mouse ortholog of human Nedd4L) and the ubiquitin-specific protease Usp2-45. Previously, Usp2-45 was shown to decrease ubiquitylation and to increase surface function of ENaC in Xenopus laevis oocytes, whereas the splice variant Usp2-69, which has a different N-terminal domain, was inactive toward ENaC. It is shown here that the catalytic core of Usp2 lacking the N-terminal domain has a reduced ability relative to Usp2-45 to enhance ENaC activity in Xenopus oocytes. In contrast, its catalytic activity toward the artificial substrate ubiquitin-AMC is fully maintained. The interaction of Usp2-45 with ENaC exogenously expressed in HEK293 cells was tested by coimmunoprecipitation. The data indicate that different combinations of ENaC subunits, as well as the α-ENaC cytoplasmic N-terminal but not C-terminal domain, coprecipitate with Usp2-45. This interaction is decreased but not abolished when the cytoplasmic ubiquitylation sites of ENaC are mutated. Importantly, coimmunoprecipitation in HEK293 cells and GST pull-down of purified recombinant proteins show that both the catalytic domain and the N-terminal tail of Usp2-45 physically interact with the HECT domain of Nedd4-2. Taken together, the data support the conclusion that Usp2-45 action on ENaC is promoted by various interactions, including through binding to Nedd4-2 that is suggested to position Usp2-45 favorably for ENaC deubiquitylation.
Identification of genes associated with heat tolerance in Arctic charr exposed to acute thermal stress
Authors: Quinn Nicole L. , McGowan Colin R. , Cooper Glenn A. , Koop Ben F. , Davidson William S.
Published: April 2011

Arctic charr is an especially attractive aquaculture species given that it features the desirable tissue traits of other salmonids and is bred and grown at inland freshwater tank farms year round. It is of interest to develop upper temperature tolerant (UTT) strains of Arctic charr to increase the robustness of the species in the face of climate change and to enable production in more southern regions. We used a genomics approach that takes advantage of the well-studied Atlantic salmon genome to identify genes that are associated with UTT in Arctic charr. Specifically, we conducted an acute temperature trial to identify temperature tolerant and intolerant Arctic charr individuals, which were subject to microarray and qPCR analysis to identify candidate UTT genes. These were compared with genes annotated in a quantitative trait locus (QTL) region that was previously identified as associated with UTT in rainbow trout and Arctic charr and that we sequenced in Atlantic salmon. Our results suggest that small heat shock proteins as well as HSP-90 genes are associated with UTT. Furthermore, hemoglobin expression was significantly downregulated in tolerant compared with intolerant fish. Finally, QTL analysis and expression profiling identified COUP-TFII as a candidate UTT gene, although its specific role is unclear given the identification of two transcripts, which appear to have different expression patterns. Our results highlight the importance of using more than one approach to identify candidate genes, particularly when examining a complicated trait such as UTT in a highly complex genome for which there is no reference genome.
MicroRNAs as new maestro conducting the expanding symphony orchestra of regenerative and reparative medicine
Authors: Sen Chandan K.
Published: April 2011

The human genome encodes 1,048 microRNAs (miRNAs). These miRNAs regulate virtually all biological processes. Leaving ignominy on the significance miRNAs behind we are approaching a new era in tissue repair where an ever expanding orchestra of events that enable tissue repair and regeneration seems to be conducted by miRNAs as the maestro. microRNAs are emerging as molecular rheostats that fine-tune and switch regulatory circuits governing tissue repair. Key elements of tissue repair such as stem cell biology, inflammation, hypoxia-response, and angiogenesis are all under the sophisticated control of a network of specific mRNAs. Embryonic stem cells lacking miRNAs lose their “stemness.” Manipulation of specific cellular miRNAs helps enhance reprogramming of somatic cells to an embryonic stem cell-like phenotype helping generate inducible pluripotent stem cells. Expression of miRNAs is subject to control by epigenetic factors. Such control influences the balance between proliferation and differentiation of stem cells. Angiomirs regulate various aspects of angiogenesis, such as proliferation, migration, and morphogenesis of endothelial cells. MiRNAs play a key role in resolution of inflammation. Hypoxia-inducible mRNAs or hypoxamirs suppress mitochondrial respiration, cause cell cycle arrest, and interfere with growth factor signaling. miRNA-210 is a good example in this category that impairs wound closure. As fine tools enabling specific and temporally controlled manipulation of cell-specific miRNAs emerge, miRNA-based therapies hold promise in facilitating tissue repair. Treatment of skin wounds has lower barriers because it lends itself to local delivery of miRNA mimics and antagonizing agents minimizing risks associated with systemic off-target toxicity.
A Program of Nutritional Education in Schools Reduced the Prevalence of Iron Deficiency in Students
Authors: García-Casal María Nieves , Landaeta-Jiménez Maritza , Puche Rafael , Leets Irene , Carvajal Zoila , Patiño Elijú , Ibarra Carlos
Published: April 2011

The objective was to determine the prevalence of iron, folates and retinol deficiencies in school children and to evaluate the changes after an intervention of nutritional education. The project was developed in 17 schools. The sample included 1,301 children (678 males and 623 females). A subsample of 480 individuals, was randomly selected for drawing blood for biochemical determinations before and after the intervention of nutritional education, which included in each school: written pre and post-intervention tests, 6 workshops, 2 participative talks, 5 game activities, 1 cooking course and 1 recipe contest. Anthropometrical and biochemical determinations included weight, height, body-mass index, nutritional status, hematocrit, serum ferritin, retinol and folate concentrations. There was high prevalence of iron (25%), folates (75%) and vitamin A (43%) deficiencies in school children, with a low consumption of fruit and vegetables, high consumption of soft drinks and snacks and almost no physical activity. The nutritional education intervention produced a significant reduction in iron deficiency prevalence (25 to 14%), and showed no effect on vitamin A and folates deficiencies. There was a slight improvement in nutritional status. This study shows, through biochemical determinations, that nutritional education initiatives and programs have an impact improving nutritional health in school children.
Invariant Sets of Impulsive Differential Equations with Particularities in ω‐Limit Set
Authors: Perestyuk Mykola , Feketa Petro
Published: April 2011

Sufficient conditions for the existence and asymptotic stability of
the invariant sets of an impulsive system of differential equations defined in the direct product of a torus and an Euclidean space are obtained.
Expression of Id-1 Is Regulated by MCAM/MUC18: A Missing Link in Melanoma Progression
Authors: Zigler Maya , Villares Gabriel J. , Dobroff Andrey S. , Wang Hua , Huang Li , Braeuer Russell R. , Kamiya Takafumi , Melnikova Vladislava O. , Song Renduo , Friedman Ran , Alani Rhoda M. , Bar-Eli Menashe
Published: April 2011

The acquisition of the metastatic melanoma phenotype is associated with increased expression of the melanoma cell adhesion molecule MCAM/MUC18 (CD146). However, the mechanism by which MUC18 contributes to melanoma metastasis remains unclear. Herein, we stably silenced MUC18 expression in two metastatic melanoma cell lines, A375SM and C8161, and conducted cDNA microarray analysis. We identified and validated that the transcriptional regulator, inhibitor of DNA binding-1 (Id-1), previously shown to function as an oncogene in several malignancies, including melanoma, was downregulated by 5.6-fold following MUC18 silencing. Additionally, we found that MUC18 regulated Id-1 expression at the transcriptional level via ATF-3, which itself was upregulated by 6.9-fold in our cDNA microarray analysis. ChIP analysis showed increased binding of ATF-3 to the Id-1 promoter after MUC18 silencing. To complement these studies, we rescued the expression of MUC18, which reversed the expression patterns of Id-1 and ATF-3. Moreover, we showed that MUC18 promotes melanoma invasion through Id-1, as overexpression of Id-1 in MUC18-silenced cells resulted in increased MMP-2 expression and activity. To our knowledge, this is the first demonstration that MUC18 is involved in cell signaling regulating the expression of Id-1 and ATF-3, thus contributing to melanoma metastasis. Cancer Res; 71(10); 3494–504. ©2011 AACR.
Increased Survival following Tumorigenesis in Ts65Dn Mice That Model Down Syndrome
Authors: Yang Annan , Reeves Roger H.
Published: April 2011

Epidemiologic results tend to suggest that adults with Down syndrome have a reduced incidence of cancer, but some studies have reached the opposite conclusion. In this study, we offer direct biological evidence in support of the notion that Down syndrome reduces incidence of multiple types of cancer. Previous studies showed that introduction of the ApcMin mutation into the Ts65Dn mouse model of Down syndrome by interbreeding caused formation of intestinal adenomas at a significantly reduced incidence compared with control (euploid) animals that did not have trisomy. To a large degree, this reduction was determined to reflect an increased dosage of the Ets2 tumor repressor gene due to trisomy. Studies of tumor grafts using Ts65Dn suggested angiogenesis as a mechanism that mediated reduced tumor growth, metastasis, and mortality in individuals with Down syndrome. To confirm and extend these findings, we employed the complex cancer mouse model NPcis, which is heterozygous for the Trp53 and Nf1 genes and through LOH develops lymphomas, sarcomas, or carcinomas with 100% penetrance. In this aggressive model, trisomy did not prevent cancer, but it nevertheless extended host survival relative to euploid littermates. However, protection in this case was not attributable to either Ets2 dosage or to reduced angiogenesis. Together, our findings indicate that the genetic complexity underlying Down syndrome supports multiple mechanisms that contribute to reduced mortality from cancer. Cancer Res; 71(10); 3573–81. ©2011 AACR.
Healing Process of the Guinea Pig Common Bile Duct after End-to-End Anastomosis: Pathological Evaluation after 6 Months
Authors: Zhang X. , Tian Y. , Xu Z. , Wang L. , Hou C. , Ling X.
Published: April 2011

Background: The healing process of an injured bile duct is always associated with stricture formation, the specific mechanism of which remains unclear. Our objective in this study was to establish a guinea pig common bile duct end-to-end anastomosis (EEA) model after total transection of the common bile duct and to assess the postoperative healing process after 6 months. Materials and Methods: Thirty-two male guinea pigs were randomly divided into 4 groups with or without operation (a control group without operation and 3 groups examined 2, 3 and 6 months after biliary EEA reconstruction, respectively). Histological, immunohistochemical (proliferating cell nuclear antigen, α-smooth muscle actin, h-caldesmon, and Bcl-2 expression) and ultrastructural characteristics were examined and evaluated. Results: Myofibroblasts (MFBs) were differentiated from smooth muscle cells by α-SMA and h-caldesmon staining. Gross inspection of operated bile ducts revealed coarctation formation at the anastomotic stoma. Histological and immunohistochemical examinations showed significant inflammatory reaction, the presence of MFBs, epithelial proliferation and glandular element hyperplasia. Bcl-2 expression decreased in groups 2 and 3, indicating an epithelial self-protecting mechanism. Conclusions: A guinea pig common bile duct EEA model was successfully established. Glandular elements, bile duct epithelial cells and MFBs all played crucial roles in the bile duct healing process. It seems important to elucidate the pathomechanisms of these components for restoring bile duct physiological function.
A Methodology to Find the Elementary Landscape Decomposition of Combinatorial Optimization Problems
Authors: Chicano Francisco , Whitley L. Darrell , Alba Enrique
Published: April 2011

A small number of combinatorial optimization problems have search spaces that correspond to elementary landscapes, where the objective function f is an eigenfunction of the Laplacian that describes the neighborhood structure of the search space. Many problems are not elementary; however, the objective function of a combinatorial optimization problem can always be expressed as a superposition of multiple elementary landscapes if the underlying neighborhood used is symmetric. This paper presents theoretical results that provide the foundation for algebraic methods that can be used to decompose the objective function of an arbitrary combinatorial optimization problem into a sum of subfunctions, where each subfunction is an elementary landscape. Many steps of this process can be automated, and indeed a software tool could be developed that assists the researcher in finding a landscape decomposition. This methodology is then used to show that the subset sum problem is a superposition of two elementary landscapes, and to show that the quadratic assignment problem is a superposition of three elementary landscapes.