bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerial surveys of fish in estuaries: a case study in Chesapeake Bay
Authors: Churnside James H. , Sharov Alexei F. , Richter Ronald A.
Published: September 2010

Churnside, J. H., Sharov, A. F., and Richter, R. A. 2011. Aerial surveys of fish in estuaries: a case study in Chesapeake Bay. – ICES Journal of Marine Science, 68: 239–244. The performance of a near-nadir, airborne lidar was compared with that of an airborne imagery (video) system for surveys of Atlantic menhaden (Brevoortia tyrannus) in Chesapeake Bay, USA. Lidar had a greater probability of detecting a school (0.93 vs. 0.73) as a result of its greater depth penetration, a lesser probability of false identification (0.05 vs. 0.13) because it was less dependent on surface conditions and ambient illumination, and less variability [coefficient of variability of 0.34 vs. 0.73] in repeated coverage of the same area. Video had a lower statistical uncertainty in school detection [relative standard error 0.04 vs. 0.07] as a result of its greater swath width. The average depth penetration of lidar was 12 m, and the average depth of detected schools was 3 m. The performance of both techniques decreased with increasing windspeed, although the effect was smaller for lidar. The school area inferred by the two techniques was nearly the same. An examination of the missed schools and false identifications in lidar and video suggest that a combination of the two techniques would reduce most of the uncertainty associated with the use of either technique alone.
Recovery and Purity of Isolated Barley Starch and Protein as Affected by Fractionation Water Temperature
Authors: Park C. S. , Baik B.‐K.
Published: September 2010

Wet fractionation of barley flours was conducted to identify appropriate fractionation water temperature considering the recovery and purity of starch and protein. In abraded hulless regular barley, yield of starch fraction, starch recovery, and purity of the protein fraction increased from 43.3 to 45.7%, from 61.7 to 64.8%, and from 37.6 to 65.2% when water temperature in fractionation was increased from 23 to 60°C. In abraded hulless waxy barley, recovery of starch with 40°C water was much greater (67.7%) than that at other temperatures (<61.7%). Starch recovery and protein purity of regular barley cultivars were higher than those of waxy barley cultivars with fractionation water of 60°C. In whole hulless barley flours fractionated with 60°C water, waxy barley flours showed similar to or higher protein purity (44.8–48.9%) than regular barley flours (42.8– 44.6%), while regular barley flours exhibited higher starch recovery (>60.6%) than waxy barley flours (<57.3%). The purity of isolated starch was >97.7%, regardless of water temperature and barley type. Considering yield and recovery of the isolated starch, and purity of the isolated protein, 60°C water for hulless regular barley and 40°C for hulless waxy barley seem to be appropriate for fractionation of barley flour for isolation of starch and protein.
First Report of Leaf Blight on Rubus brasiliensis Caused by Colletotrichum acutatum in Brazil
Authors: Lopes U. P. , Zambolim L. , Duarte H. S. S. , Cabral P. G. C. , Pereira O. L. , Lopes U. N. , Zambolim E. M.
Published: September 2010

There are more than 300 blackberry (Rubus) species worldwide. Rubus brasiliensis Mart. is a native Brazilian species found in tropical forests. In January 2009, samples of R. brasiliensis with severe leaf blight were collected from an area of rain forest in the city of São Miguel do Anta, State of Minas Gerais, Brazil. Dark spots began developing in the young leaves and progressed to necrotic spots with occasional twig dieback. From the spots, a fungus was isolated with the following morphology: acervuli that were 20 to 50.0 × 50 to 125.0 μm and hyaline amerospores that were ellipsoid and fusiform and 7.5 to 23.75 × 2.5 to 5.0 μm. On the basis of these morphological characteristics, the fungus was identified as Colletotrichum acutatum. In Brazil, C. acutatum is reported in apple, citrus, strawberry, peach, plum, nectarine, olive, medlar, and yerba-mate, but it was not reported as the causal agent of leaf blight in R. brasiliensis. A sample was deposited in the herbarium at the Universidade Federal de Viçosa, Minas Gerais, Brazil (VIC 31210). One representative isolate, OLP 571, was used for pathogenicity testing and molecular studies. Identity was confirmed by amplifying the internal transcribed spacer (ITS) regions of the ribosomal RNA with primers ITS4 (3), CaInt2 (a specific primer for C. acutatum [2]) and CgInt (a specific primer for C. gloeosporioides [1]). Isolates of C. acutatum (DAR78874 and DAR78876) and C. gloeosporioides (DAR78875) obtained from Australian olive trees were used as positive controls. The primers ITS4 and CaInt2 amplified a single DNA product of 500 bp expected for C. acutatum. OLP 571 was grown for 7 days on potato dextrose agar. Young leaves of R. brasiliensis were inoculated with a conidial suspension (106 conidia/ml) on young leaves. Inoculated plants were maintained in a moist chamber for 2 days and subsequently in a greenhouse at 25°C. Necrotic spots similar to those described were detected on young leaves 3 days after the inoculation. Control leaves, on which only water was sprayed, remained healthy. The same fungus was reisolated from the inoculated symptomatic tissues. To our knowledge, this is the first report of C. acutatum causing leaf blight in the native species of R. brasiliensis in Brazil.

References: (1) P. R. Mills et al. FEMS Microbiol. Lett. 98:137, 1999. (2) S. Sreenivasaprasad et al. Plant Pathol. 45:650, 1996. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.
First Report of Potato mop-top virus in North Dakota
Authors: David N. , Mallik I. , Crosslin J. M. , Gudmestad N. C.
Published: September 2010

Potato mop-top virus (PMTV) is the type member of the genus Pomovirus. PMTV is an important pathogen of potato, causing significant economic losses in Northern Europe, North and South America, and Asia (3). PMTV in the United States was first reported in Maine (2). PMTV is vectored by the plasmodiophoromycete Spongospora subterranea cv. subterranea, which causes powdery scab of potato (1). S. subterranea and PMTV are usually associated with cool and humid environments. In the spring of 2010, six potato tubers of cv. Russet Burbank were received from a commercial potato farm in Grand Forks County in North Dakota. The tubers had multiple, internal, concentric, necrotic arcs and circles. The presence of PMTV in the necrotic lesions was verified by a positive double-antibody sandwich-ELISA (Agden Ltd., Ayr, Scotland). The tuber lesions had an absorbance value (405 nm) at least two times greater than that of the negative control sample, which consisted of a healthy tuber. Total RNA was extracted from lesions of six different tubers that tested positive by ELISA using a Total RNA Isolation kit (Promega Corp. Madison, WI). These extracts were tested for PMTV by reverse transcription (RT)-PCR using two different sets of primers. The primer set H360/C819 targeted the coat protein (CP) of PMTV and yielded an amplicon of 460 bp (4). The amplicons generated from the necrotic lesions were cloned (TOPO Cloning; Invitrogen, Carlsbad, CA) and sequenced. Another set of primers, pmtF4/pmtR4, designed to bind to a region in RNA 2 of PMTV, yielded a 417-bp amplicon that also was cloned and sequenced (3). The sequences from all six tuber lesions were identical for the respective primer sets. A consensus sequence for each primer pair was submitted to GenBank (Accession No. HM776171 for primers pmtF4/pmtR4 and No. HM776172 for primers H360/C819). The sequences obtained from the H360/C819 and pmtF4/pmtR4 amplicons were 99% identical to the corresponding regions of PMTV isolates from Northern Europe (GenBank Accession Nos. AM503629 and AJ277556, respectively). Freeze-dried, necrotic tuber tissue from all six tubers was also tested at a USDA Laboratory in Prosser, WA by RT-PCR with the H360/C819 primer pair (4), confirming the results above. Cloning and sequencing of one of the amplicons revealed 100% similarity to the sequence described above for these primers (GenBank Accession No. HM776172), confirming the presence of PMTV in the symptomatic tubers. None of the symptomatic tubers tested positive for Tobacco rattle virus, Tomato spotted wilt virus, Alfalfa mosaic virus, Potato leafroll virus, or the necrotic strains of Potato virus Y by RT-PCR. To our knowledge this is the first report of PMTV in North Dakota.

References: (1) R. A. C. Jones and B. D. Harrsion. Ann. Appl. Biol. 63:1, 1969. (2) D. H. Lambert et al. Plant Dis. 87:872, 2003. (3) J. Santala et al. Ann. Appl. Biol. Online publication. DOI: 10.1111/j.1744-7348.2010.00423.x (4) H. Xu et al. Plant Dis. 88:363, 2004.
Foster carer perceptions of support and training in the context of high burden of care
Authors: Murray Lyn , Tarren‐Sweeney Michael , France Karyn
Published: September 2010

The challenges of providing sensitive and structured care for children in foster care go well beyond normative experiences of parenting. The present paper describes a mixed‐methods study of foster carers' perceived need for support and training, referenced to estimates of their burden of care. Semi‐structured interviews were conducted with 17 foster carers in the Canterbury region of New Zealand. Carers' perceived need for support and training were identified through qualitative analysis of interviews using domain analysis method. Carers' burden of care was estimated from the Parenting Stress Index and from a measure of carers' encounters with children's emotional, behavioural and relationship difficulties that was designed for the present study (the Caregiver Behavioural Encounters Index). Foster carers reported substantive, unmet needs for support and training. Foster carers also reported high parenting stress and encounters with a wide range of children's mental health difficulties, including both uncommon and severe difficulties, which together represent an exceptional burden of care. Carers' highest priority need was for training and support on managing and responding to children's mental health difficulties, while their greatest existing support came from Caregiver Liaison Social Workers and other carers. The findings suggest a number of critical implications for practice.
Evaluation of rFVIIa (NovoSeven) in Glanzmann patients with thromboelastogram
Authors: LAK M. , SCHARLING B. , BLEMINGS A. , SHARIFIAN R. , MALEKI Z. , DARAEE A. , ARJMAND A. R. , HEDNER U.
Published: September 2010

Summary.  Glanzmann thrombasthenia (GT) is a rare platelet function disorder characterized by a defect in fibrinogen binding to platelet membrane glycoprotein (GP) IIb/IIIa. Recombinant FVIIa (rFVIIa) is a haemostatic agent approved for the treatment of haemophilia patients with inhibitors, patients with acquired haemophilia and in EU also for treatment of factor VII (FVII)‐deficient patients and GT patients with antibodies to GPIIb‐IIIa. The present study was conducted to evaluate the use of the whole blood test system, rotational thrombelastometry (ROTEM), in measuring the overall haemostasis potential of rFVIIa in 28 GT patients treated with rFVIIa. The correlation of administered rFVIIa and time to start fibrin formation and clot dynamic/stability was assessed and correlation to the clinical response was elucidated. Assessments were performed on predose blood samples spiked with four different concentrations of rFVIIa and whole blood samples taken at 10 and 120 min following dosing. ROTEM parameters clotting time (CT), clot formation time (CFT) and maximum clot firmness (MCF) were measured. Both ex vivo and in vivo data showed beneficial effects on CT in the presence of rFVIIa, but no effect of added rFVIIa was seen on CFT and MCF. In conclusion, the use of thrombelastography at least in the modified form of ROTEM seems to be of limited use in predicting an adequate dose of rFVIIa in GT patients. A good clinical haemostatic response was recorded in spite of the limited changes in the ROTEM pattern supporting the conclusion that ROTEM should not be the method of choice for monitoring rFVIIa therapy in Glanzmann patients.
Climate change‐linked range expansion of Nathusius’ pipistrelle bat, Pipistrellus nathusii (Keyserling & Blasius, 1839)
Authors: Lundy Mathieu , Montgomery Ian , Russ Jon
Published: September 2010

Aim  To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius’ pipistrelle) in the United Kingdom (UK).

Location  We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species’ historical range in continental Europe.

Methods  A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940–2006) and CORINE land cover data. This model was applied to historical and projected climate data to examine changes in suitable range (1940–2080) of this species. We tested the predictive ability of the model with known records in the UK after 2006 and applied the model to the species’ known range in Europe.

Results  The distribution of P. nathusii was related positively to the area of water bodies, woodland and small areas of urbanization, and negatively related to the area of peat/heathland. Species records were associated with higher minimum temperatures, low seasonal variation in temperature and intermediate rainfall. We found that suitable areas have existed in the UK since the 1940s and that these have expanded. The model had high predictive power when applied to new records after 2006, with a correct classification rate of 70%, estimated by receiver operating characteristic analysis. Based on climate projections, our model suggests a potential twofold increase in the area suitable for P. nathusii in the UK by 2050. The single most influential climate variable contributing to range increase was the projected increase in minimum temperature. When applied to Europe, the model predictions had best predictive capability of known records in western areas of the species’ range, where P. nathusii is present during the winter.

Main conclusions  We show that a mobile, migratory species has adapted its range in response to recent climate change on a continental scale. We believe this may be the first study to demonstrate a case of range change linked to contemporary climate change in a mammal species in Europe.
Cumulative cultural dynamics and the coevolution of cultural innovation and transmission: an ESS model for panmictic and structured populations
Authors: LEHMANN L. , FELDMAN M. W. , KAEUFFER R.
Published: September 2010

When individuals in a population can acquire traits through learning, each individual may express a certain number of distinct cultural traits. These traits may have been either invented by the individual himself or acquired from others in the population. Here, we develop a game theoretic model for the accumulation of cultural traits through individual and social learning. We explore how the rates of innovation, decay, and transmission of cultural traits affect the evolutionary stable (ES) levels of individual and social learning and the number of cultural traits expressed by an individual when cultural dynamics are at a steady‐state. We explore the evolution of these phenotypes in both panmictic and structured population settings. Our results suggest that in panmictic populations, the ES level of learning and number of traits tend to be independent of the social transmission rate of cultural traits and is mainly affected by the innovation and decay rates. By contrast, in structured populations, where interactions occur between relatives, the ES level of learning and the number of traits per individual can be increased (relative to the panmictic case) and may then markedly depend on the transmission rate of cultural traits. This suggests that kin selection may be one additional solution to Rogers's paradox of nonadaptive culture.
Three‐month‐old infants attribute goals to a non‐human agent
Authors: Luo Yuyan
Published: September 2010

The present research examined whether 3‐month‐old infants, the youngest found so far to engage in goal‐related reasoning about human agents, would also act as if they attribute goals to a novel non‐human agent, a self‐propelled box. In two experiments, the infants seemed to have interpreted the box’s actions as goal‐directed after seeing the box approach object A as opposed to object B during familiarization. They thus acted as though they expected the box to maintain this goal and responded with increased attention when the box approached object B during test. In contrast, when object B was absent during familiarization and introduced afterwards, the infants’ responses were consistent with their having recognized that they had no information to predict which of the two objects the box should choose during test and therefore responded similarly when the box approached either object. However, if object B was absent during familiarization and object A was in different positions but the box persistently approached it, thus demonstrating equifinal variations in its actions, the infants again acted as though they attributed to the box a goal directed towards object A and expected the box to maintain this goal even when object B was introduced and hence responded with prolonged looking when the box failed to do so during test. These results are consistent with the notion that (a) infants as young as 3 months appear to attribute goals to both human and non‐human agents, and (b) even young infants can use certain behavioral cues, e.g. equifinal variations in agents’ actions, to make inferences about agents’ goals.
Making Movements Possible: Transportation Workers and Mobility in West Africa
Authors: Mechlinski Timothy
Published: September 2010

This article concerns the social process of mobility control in four West African countries: Burkina Faso, Côte d’Ivoire, Mali, and Ghana. Migration has long been an important aspect of West African social, cultural, and political life. This study explores everyday enforcement of international and internal mobility control, and the ways in which Africans respond to and resist the actions of security agents. I accomplish this using ethnographic evidence gathered when travelling over 10,000 miles in Burkina Faso, Mali, Ghana, and Côte d’Ivoire over a period of nine months. In addition, data were gathered through participant observation while crossing international borders 23 times in a sub‐region of West Africa, and participating in 169 security control checkpoints in total. This evidence is supplemented by 29 interviews with transportation workers across the four countries studied. Augmenting the traditional social science literature on migrant networks with an approach proposed by development economists, this article shows that transportation workers play an essential role in mobility control in West Africa. The theoretical insights derived here contribute to a larger project of bringing borders and transportation into the same frame of reference as migration in academic study. This project sees movement through interaction, rather than simply through the systems approach so commonly applied in the literature and shows that in the countries under study there exist unstated, implicit social norms among transportation workers, their clients, and security agents, which constitute a key mechanism for migration. These actors operate in a series of structured relationships, which can be described as institutionalised, and which create a series of important exchanges governing movement in the sub‐ region.
Voltage‐dependent anion channel as a resident protein of lipid rafts: post‐transductional regulation by estrogens and involvement in neuronal preservation against Alzheimer’s disease
Authors: Herrera Jose Luis , Diaz Mario , Hernández‐Fernaud Juan Ramón , Salido Eduardo , Alonso Rafael , Fernández Cecilia , Morales Araceli , Marin Raquel
Published: September 2010

J. Neurochem. (2011) 116, 820–827.

The voltage‐dependent anion channel, VDAC, is present at the neuronal membrane, where it appears to participate, among others, in the extrinsic apoptotic pathway and in the modulation of amyloid‐beta induced injury, suggesting the involvement of this channel in Alzheimer's disease (AD) neurotoxicity. VDAC is also highly concentrated in neuronal lipid raft microdomains of different mouse and human cognitive areas, where it has been shown associated with estrogen receptor alpha (ERα), as a part of a `signalosome' that may activate some intracellular signal transduction. At the plasma membrane level, estrogens and antiestrogens (tamoxifen) have been demonstrated to exert rapid antagonist effects on the activation of VDAC, through their distinct effects on the channel post‐transductional modulation. Therefore, part of the alternative mechanisms of estrogen related to neuroprotection against amyloid‐beta may involve VDAC phosphorylation, in order to maintain the channel in an unactivated (closing) state. Interestingly, VDAC‐ERα association has been shown to be disrupted in neuronal lipid rafts of AD brains, in correlation with the aberrant lipid composition observed in these microstructures, suggesting that disturbance of protein interactions may be related to variation in the physico‐chemical properties of these microdomains.
Floristic homogenization as a teleconnected trend in oceanic islands
Authors: Castro Sergio A. , Daehler Curtis C. , Silva Luis , Torres‐Santana Christian W. , Reyes‐Betancort Jorge A. , Atkinson Rachel , Jaramillo Patricia , Guezou Anne , Jaksic Fabian M.
Published: September 2010

Aim  We searched for evidence of floristic homogenization in widespread oceanic archipelagos.

Location  Twelve oceanic archipelagos in the Atlantic and Pacific oceans: Ascension, Azores, Canary, Cape Verde, Desventuradas, Easter, Galápagos, Hawaii, Juan Fernández, Madeira, Puerto Rico and Savage.

Methods  By using Jaccard’s index, we established the floristic similarity between pairs of archipelagos at two stages: original (pre‐European; Jo) and current flora (Jc). Then, we calculated ΔJ = Jc–Jo, where positive differences imply that similarity has increased floristic homogenization.

Results  We found that floristic similarity increased fourfold on average, from 1.6% to 6.3% for original and current floras, respectively. In fact, we recorded 64 cases in which floristic similarity increased and only two in which it decreased. The importance of invasions exceeds that of extirpations as a driver of biotic change by more than an order of magnitude (2679 versus 142 species, respectively).

Main conclusions  The vascular floras of these 12 insular oceanic systems have increased in compositional similarity, a phenomenon consistent with the trend towards biotic homogenization. It can be characterized as a teleconnected process that operates across vast geographical distances, driven by the unprecedented capacity of humans for translocation. Trends in biotic homogenization differ depending on the geographical location (i.e. Pacific < Atlantic archipelagos) and phylogenetic groups (island vascular plants > island birds reported in a previous study), emphasizing the complexity of biotic change.
Selfishness, altruism, and inequality aversion toward consumers and farmers
Authors: Lusk Jayson L. , Briggeman Brian C.
Published: September 2010

One hypothesis explaining the persistence of farm programs in the United States is the public's altruism toward farmers. We utilize economic experiments to identify the motivations of selfishness, altruism, and inequality aversion toward anonymous members of the general population and toward different types of farmers. We find that people are generally less selfish and more altruistic toward small farmers than other members of the population. We also find that (i) people are more averse to inequality in a market‐like setting as compared to a nonmarket setting, (ii) there is significant heterogeneity across people in terms of other‐regarding preferences, and (iii) experimental choices accurately predict preferences for “real‐world” income re‐distribution policies that entail giving up one's own money to benefit farmers, but fail to predict preferences for policies that redistribute others’ incomes.
Functional classification of scaffold proteins and related molecules
Authors: Buday László , Tompa Péter
Published: September 2010

In this series of four minireviews the field of scaffold proteins and proteins of similar molecular/cellular functions is overviewed. By binding and bringing into proximity two or more signaling proteins, these proteins direct the flow of information in the cell by activating, coordinating and regulating signaling events in regulatory networks. Here we discuss the categories of scaffolds, anchors, docking proteins and adaptors in some detail, and using many examples we demonstrate that they cover a wide range of functional modes that appear to segregate into three practical categories, simple proteins binding two partners together (adaptors), larger multidomain proteins targeting and regulating more proteins in complex ways (scaffold/anchoring proteins) and proteins specialized to initiate signaling cascades by localizing partners at the cell membrane (docking proteins). It will also be shown, however, that the categories partially overlap and often their names are used interchangeably in the literature. In addition, although not usually considered as scaffolds, several other proteins, such as regulatory proteins with catalytic activity, phosphatase targeting subunits, E3 ubiquitin ligases, ESCRT proteins in endosomal sorting and DNA damage sensors also function by bona fide scaffolding mechanisms. Thus, the field is in a state of continuous advance and expansion, which demands that the classification scheme be regularly updated and, if needed, revised.
Phenotype Prediction of Non‐Synonymous Single‐Nucleotide Polymorphisms in Human ATP‐Binding Cassette Transporter Genes
Authors: Wang Lin‐Lin , Liu Ya‐He , Meng Lu‐Lu , Li Chun Guang , Zhou Shu‐Feng
Published: September 2010

Abstract:  A large number of non‐synonymous single‐nucleotide polymorphisms (nsSNPs) have been found in human genome, but there is poor knowledge on the relationship between the genotype and phenotype of these nsSNPs. Human ATP‐binding cassette (ABC) transporters are able to transport a number of important substrates including endogenous and exogenous compounds. This study aimed to predict the phenotypical impact of nsSNPs of human ABC transporter genes, and the predicted results were further validated by reported phenotypical data from site‐directed mutagenesis and clinical genetic studies. One thousand and six hundred thirty‐two nsSNPs were found from 49 human ABC transporter genes. Using the PolyPhen and SIFT algorithms, 41.8–53.6% of nsSNPs in ABC transporter genes were predicted to have an impact on protein function. The prediction accuracy was up to 63–85% when compared with known phenotypical data from in vivo and in vitro studies. There was a significant concordance between the prediction results using SIFT and PolyPhen. Of nsSNPs predicted as deleterious, the prediction scores by SIFT and PolyPhen were significantly related to the number of nsSNPs with known phenotypes confirmed by experimental and human studies. The amino acid substitution variants are supposed to be the pathogenetic basis of increased susceptibility to certain diseases with Mendelian or complex inheritance, altered drug resistance and altered drug clearance and response. Predicting the phenotypic consequence of nsSNPs using computational algorithms may provide a better understanding of genetic differences in susceptibility to diseases and drug response. The prediction of nsSNPs in human ABC transporter genes would be useful hints for further genotype–phenotype studies.
One level density of low-lying zeros of families of L-functions
Authors: Gao Peng , Zhao Liangyi
Published: September 2010

In this paper, we prove some one level density results for the low-lying zeros of families of L-functions. More specifically, the families under consideration are that of L-functions of holomorphic Hecke eigenforms of level 1 and weight k twisted with quadratic Dirichlet characters and that of cubic and quartic Dirichlet L-functions.
Transfert d’intégrales orbitales pour le groupe métaplectique
Authors: Li Wen-Wei
Published: September 2010

We set up a formalism of endoscopy for metaplectic groups. By defining a suitable transfer factor, we prove an analogue of the Langlands–Shelstad transfer conjecture for orbital integrals over any local field of characteristic zero, as well as the fundamental lemma for units of the Hecke algebra in the unramified case. This generalizes prior work of Adams and Renard in the real case and serves as a first step in studying the Arthur–Selberg trace formula for metaplectic groups.
Differential effects of Na+–K+ ATPase blockade on cortical layer V neurons
Authors: Anderson Trent R. , Huguenard John R. , Prince David A.
Published: September 2010

Sodium–potassium ATPase (‘Na+–K+ ATPase’) contributes to the maintenance of the resting membrane potential and the transmembrane gradients for Na+ and K+ in neurons. Activation of Na+–K+ ATPase may be important in controlling increases in intracellular sodium during periods of increased neuronal activity. Down‐regulation of Na+–K+ ATPase activity is implicated in numerous CNS disorders, including epilepsy. Although Na+–K+ ATPase is present in all neurons, little is known about its activity in different subclasses of neocortical cells. We assessed the physiological properties of Na+–K+ ATPase in fast‐spiking (FS) interneurons and pyramidal (PYR) cells to test the hypothesis that Na+–K+ ATPase activity would be relatively greater in neurons that generated high frequency action potentials (the FS cells). Whole‐cell patch clamp recordings were made from FS and PYR neurons in layer V of rat sensorimotor cortical slices maintained in vitro using standard techniques. Bath perfusion of Na+–K+ ATPase antagonists (ouabain or dihydro‐ouabain) induced either a membrane depolarization in current clamp, or inward current under voltage clamp in both cell types. PYR neurons were divided into two subpopulations based on the amplitude of the voltage or current shift in response to Na+–K+ ATPase blockade. The two PYR cell groups did not differ significantly in electrophysiological properties including resting membrane potential, firing pattern, input resistance and capacitance. Membrane voltage responses of FS cells to Na+–K+ ATPase blockade were intermediate between the two PYR cell groups (P < 0.05). The resting Na+–K+ ATPase current density in FS interneurons, assessed by application of blockers, was 3‐ to 7‐fold larger than in either group of PYR neurons. Na+–K+ ATPase activity was increased either through direct Na+ loading via the patch pipette or by focal application of glutamate (20 mm puffs). Under these conditions FS interneurons exhibited the largest increase in Na+–K+ ATPase activity. We conclude that resting Na+–K+ ATPase activity and sensitivity to changes in internal Na+ concentration vary between and within classes of cortical neurons. These differences may have important consequences in pathophysiological disorders associated with down‐regulation of Na+–K+ ATPase and hyperexcitability within cortical networks.
Modeling deep ocean shipping noise in varying acidity conditions
Authors: Udovydchenkov Ilya A. , Duda Timothy F. , Doney Scott C. , Lima Ivan D.
Published: September 2010

Possible future changes of ambient shipping noise at 0.1–1 kHz in the North Pacific caused by changing seawater chemistry conditions are analyzed with a simplified propagation model. Probable decreases of pH would cause meaningful reduction of the sound absorption coefficient in near-surface ocean water for these frequencies. The results show that a few decibels of increase may occur in 100 years in some very quiet areas very far from noise sources, with small effects closer to noise sources. The use of ray physics allows sound energy attenuated via volume absorption and by the seafloor to be compared.
Ocean acidification and its impact on ocean noise: Phenomenology and analysis
Authors: Reeder D. Benjamin , Chiu Ching-Sang
Published: September 2010

Ocean acidification has been observed since the beginning of the industrial era and is expected to further reduce ocean pH in the future. A significant increase in ocean noise has been suggested based upon the percentage change in acoustic absorption coefficient at low frequencies. Presented here is an analysis using transmission loss models of all relevant loss mechanisms for three environments experiencing a significant near-surface pH reduction of 8.1–7.4. Results show no observable change in the shallow water and surface duct environments, and a statistically insignificant change of less than 0.5 dB for all frequencies in the deep water environment.
Sonar detection of jittering real targets in a free-flying bat
Authors: Goerlitz Holger R. , Geberl Cornelia , Wiegrebe Lutz
Published: September 2010

The auditory system measures time with exceptional precision. Echolocating bats evaluate the time delay between call and echo to measure object range. An extreme and disputed result on ranging acuity was found in the virtual delay jitter experiments. In these studies, echoes with alternating delays were played back to bats, which detected a jitter down to 10 ns, corresponding to a ranging acuity of 1.7 μm. The current study was designed to measure the ranging acuity of the nectarivorous bat Glossophaga soricina under semi-natural conditions. Three free-flying bats were trained to discriminate between a stationary loudspeaker membrane and a membrane sinusoidally vibrating at 10 Hz. At detection threshold, the average peak-to-peak displacement of the vibrating membrane was 13 mm, corresponding to an echo delay jitter of 75 μs. The perceived jitter from call to call, which depends on the pulse interval and the call emission time relative to the membrane phase, was simulated for comparison with the virtual jitter experiments. This call-to-call jitter was between 20 to 25 μs (ca. 4 mm ranging acuity). These thresholds between 20 and 75 μs (4–13 mm) fall within both ecologically and physiologically plausible ranges, allowing for sufficiently precise navigation and foraging.
Vibration of elliptic cylindrical shells: Higher order shell theory
Authors: Hayek Sabih I. , Boisvert Jeffrey E.
Published: September 2010

The equations for the free vibration of an elliptic cylindrical shell of constant thickness were derived using a Ritz approach. A higher order shell theory is employed that includes the effects of shear deformation, rotary inertia, and symmetric and antisymmetric thickness stretch deformations. The frequency-wavenumber spectrum has seven branches: flexural, extensional, torsional, two thickness shear, and two thickness stretch. The resulting seven coupled algebraic equations are symmetric and positive definite. The shell has a constant thickness, h, finite length, L, and is “simply supported” at its ends, (z=0,L), where z is the axial coordinate. The elliptic cross-section is defined by the shape parameter, a, and the half-length of the major axis, l. The modal solutions are expanded in a doubly infinite series of comparison functions in terms of circular functions in the angular and axial coordinates. Numerical results for the natural frequencies were obtained for two values of h/l and L/l, and various shape parameters, including the limiting case of a simply supported cylindrical shell (a≈100).
Low sidelobe limited diffraction beams in the nonlinear regime
Authors: Holm Sverre , Prieur Fabrice
Published: September 2010

In linear propagation, sidelobe levels of Bessel limited diffraction beams are only about 8 dB down relative to the mainlobe. In the nonlinear regime, these beams will have a region near the source where the side-lobe level of the second harmonic is 16 dB down, but this region has usually been considered to be so small that it is of little practical interest. In this paper it is shown that when there are only 1 to 3 sidelobes in a finite aperture Bessel beam, the second harmonic field will have low sidelobes for distances up to half of the depth of field. This result is backed up by simulations. In a medium with absorption, previous theory has shown that the sidelobes of the Bessel beam will also be reduced but only for absorption that was too high to be of practical use. Simulations presented here show that for breast tissue, which only has about 10% of the absorption of previous criteria, one will still get sidelobes which are comparable to that of a rectangular aperture even when the sidelobes would be high in a non-absorbing medium.
Encoding pitch contours using current steering
Authors: Luo Xin , Landsberger David M. , Padilla Monica , Srinivasan Arthi G.
Published: September 2010

This study investigated cochlear implant (CI) users’ ability to perceive pitch cues from time-varying virtual channels (VCs) to identify pitch contours. Seven CI users were tested on apical, medial, and basal electrode pairs with stimulus durations from 100 to 1000 ms. In one stimulus set, 9 pitch contours were created by steering current between the component electrodes and the VC halfway between the electrodes. Another stimulus set only contained 3 pitch contours (flat, falling, and rising). VC discrimination was also tested on the same electrodes. The total current level of dual-electrode stimuli was linearly interpolated between those of single-electrode stimuli to minimize loudness changes. The results showed that pitch contour identification (PCI) scores were similar across electrode locations, and significantly improved at longer durations. For durations longer than 300 ms, 2 subjects had nearly perfect 9-contour identification, and 5 subjects perfectly identified the 3 basic contours. Both PCI and VC discrimination varied greatly across subjects. Cumulative d′ values for VC discrimination were significantly correlated with 100-, 200-, and 500-ms PCI scores. These results verify the feasibility of encoding pitch contours using current steering, and suggest that identification of such pitch contours strongly relies on CI users’ sensitivity to VCs.
Stress-Induced Angiogenesis
Authors: Wong Wei
Published: September 2010

Blocking the activity of the stress sensor IRE1 reduces angiogenesis in gliomas.
Moving in 2D Versus 3D
Authors: Gough Nancy R.
Published: September 2010

The actin-depolymerizing protein cofilin is required for T cell movement in a 3D environment but not a 2D one.
Gee-Up, NEDD8
Authors: Hurtley Stella M.
Published: September 2010

Pathogenic bacterial proteins interfere with eukaryotic ubiquitination pathways to induce cytopathic effects.
Decomposition of ethylene on palladium surfaces at 200 °C
Authors: Kopešťanský Josef
Published: September 2010

The interaction of ethylene with surfaces of palladium films at 200 °C was studied by work function and volumetric measurements and by analysis of the gaseous reaction products. Intensive dehydrogenation of the adsorbed ethylene, accompanied by desorption of hydrogen into the gaseous phase, was observed. The surface adsorption layer was found to comprise hydrocarbon species with the H/C ratio 0.5 (independent of the degree of surface coverage) and surface-bonded hydrogen whose amount, per adsorbed ethylene molecule, dropped rapidly with increasing degree of surface coverage by the hydrocarbon species.
Possibility of determination of some derivatives of pterin important in the diagnostics of malignant tumours by using differential pulse polarography
Authors: Kočmíd Václav , Podolák Miroslav , Čoupek Jiří , Andrýsek Oskar
Published: September 2010

The polarographic behaviour of 6,7-dimethylpterin, xanthopterin, 6-pterinaldehyde, neopterin and 6-hydroxymethylpterin was investigated. These compounds are suitably determined by employing differential pulse polarography; some results suggest the possibility of their determination by cathodic stripping voltammetry with adsorptive accumulation. For all compounds, the effect of pH on polarographic reduction was examined. Under optimal conditions, the calibration curve of all compounds under investigation was linear in the range 2 . 10-6 - 1 . 10-7 mol/l and the detection limit was below 1 . 10-7 mol/l.
A contribution to the problem of turbulent mass transfer at high values of the Schmidt number and to the hydrodynamics of the turbulent boundary layer
Authors: Kolář Václav , Vašák František , Brož Zdeněk
Published: September 2010

It has been shown in the paper that under the turbulence (Re > 104) and at high values of the Schmidt number (Sc > 103), when the principal resistance to mass transfer is concentrated in the laminar layer immediately adhering to the interface, significant instabilities appear induced by the turbulent disturbances in the neighbouring transition layer, or by the discontinuities at the interface. Parameters have been determined characterizing this phenomenon on the basis of experimental data and their values have been compared with the data published in the literature as characteristics of the periodic viscous sublayers.
Catalytic hydrogenation of unsaturated organic acids and their sodium salts
Authors: Červený Libor , Fialová Eva , Růžička Vlastimil
Published: September 2010

Catalytic hydrogenation of unsaturated organic acids in methanol and their sodium salts in water was studied at 20 °C and atmospheric pressure of hydrogen using a catalyst of 3% Pd on activated carbon. The effect of the structure of the acids and salts on the hydrogenation rates is discussed.
Electrophilic substitution reactions of furo[3,2-b]pyrrole derivatives
Authors: Kraľovičová Eva , Krutošíková Alžbeta , Kováč Jaroslav , Dandárová Miloslava
Published: September 2010

Formylation of ethyl 4H-furo[3,2-b]pyrrole-5-carboxylate and its N-methyl analogue afforded the 2-formyl products Ia,b which on nitration yielded 2-nitro derivatives IIc,d. Formylation, nitration, Mannich reaction, and copulation of the starting products, having position 2 occupied by an aryl, took place at the pyrrole ring.
Relationship between biological activity of phenols and their physico-chemical parameters
Authors: Polster Miroslav , Rittich Bohuslav , Žaludová Renata
Published: September 2010

The present work deals with the relationship between biological activities of differently substituted phenols and their physico-chemical parameters expressing the influence of hydrophobic, electronic and steric factors. The testing was performed with the fungi Trychophyton gypseum and Trychophyton gypseum var. Kaufman-Wolf and the yeast Candida albicans. Significant relationship between biological activity and pKA values was calculated. The interactions between individual factors as well as the influence of the position of substituents on quantitative structure-activity relationships are discussed.
Structure and ring inversion of 2-pyrrolidone. Semiempirical quantum chemical study and analysis of X-ray data
Authors: Bánhegyi Györgi , Ángyán János , Kajtár Márton
Published: September 2010

The equilibrium structure and the ring inversion potential of the 2-pyrrolidone molecule has been studied by the semiempirical CNDO/2 and INDO methods. The calculated geometrical parameters are compared with experimental X-ray data with earlier Consistent Force Field (CFF) results. The ring inversion is analyzed in terms of two types of puckering coordinates. The CNDO/2 method was found to yield a strongly nonplanar 2-pyrrolidone ring due to the overestimation of the amide pyramidality while INDO calculations led to a slightly nonplanar ring with an extremely low barrier of inversion.
Photocyanation of 3,4-dimethoxy-1-nitrobenzene. A quantitative study
Authors: Kuzmič Petr , Souček Milan
Published: September 2010

UV photolysis (365 nm) of 3,4-dimethoxy-1-nitrobenzene in the presence of potassium cyanide leading to 3-cyano-4-methoxy-1-nitrobenzene was subjected to a quantitative photokinetic study. The reaction exhibits a second order kinetics with respect to the nucleophile and is effectively quenched by molecular oxygen as well as 2,4-hexadienoic acid. The excited triplet lifetime of 0.9 microseconds was determined on the basis of the dependence of quantum yield on the nucleophile and quencher concentrations in 50% aqueous tert-butanol. The quantum yield of intersystem crossing is at least 0.38 in the same solvent; bimolecular rate constant for the interaction of triplet 3,4-dimethoxy-1-nitrobenzene with cyanide anion has the value of 5.6 . 108 l . mol-1s-1, which is approximately one half of the rate constant for diffusion controlled quenching. Quantum yield of the reaction is strongly dependent on the water content in mixtures with tert-butanol and increases from 0.04 in water to 0.68 in 88% tert-butanol.
Derivatives of 3,4-dihydro-3-thioxo-2-quinoxalinylacetic acid
Authors: Toman Jaromír , Klicnar Jiří
Published: September 2010

Ethyl 3,4-dihydro-4-methyl-3-thioxo-2-quinoxalinylacetate has been prepared by thionation of the 3-oxo derivative. The mechanism is discussed of the reaction of this ester with diethylamine giving the two non-isomerizing ketimine-enamine tautomers and 1,2-dihydro-1,3-dimethyl-2-thioxoquinoxaline. Structure has been studied of the reaction product of both this derivative and its 3-oxo analogue with sodium hydride in dimethyl sulphoxide.
Solvolytic reactions of empiric 3-methanesulfonyloxy-7-benzoyloxy-5β,6β-cyclopropanocholestanes
Authors: Kohout Ladislav , Sethi Vijay Kumar , Zajíček Jaroslav , Kasal Alexander
Published: September 2010

Acetolysis of 3-methanesulfonyloxy-7-benzoyloxy-5β,6β-cyclopropanocholestanes with various configurations in positions 3 and 7 is described and the products are assigned structure using spectral methods. The 7-substituted compounds show greater propensity to elimination reactions than the 7-unsubstituted ones.
Phase transitions of natural scolecite
Authors: Rykl Drahoš , Chalupský Vojtěch , Pechar František
Published: September 2010

Based on DTA and TGA, the natural zeolite scolecite (Teigarhorn, Iceland) was subjected to decomposition at temperature of 20, 250, 300, 400, 450, 500, 590, 720 and 1 000 °C; the decomposition products were identified by powder X-ray diffraction analysis and infrared spectroscopy. The crystal structure of scolecite remains stable up to 200 °C only; then it begins to transform into a metaphase and at temperatures above 350 °C, into an amorphous phase from which anortite and the high-temperature quartz modification form at 700 - 1 000 °C. Dehydration of scolecite occurs in four steps. A considerable weakening of the O-H stretching vibrations and vanishing of the water bending vibrations occur at 450 °C. The remaining water splits heterolytically and forms structural O-H groups which persist up to 1 00 °C.
Kinetic acidity function and solvolysis of 3-hydroxy-1,3-diphenyltriazenes
Authors: Pytela Oldřich , Štumrová Stanislava , Ludwig Miroslav , Večeřa Miroslav
Published: September 2010

Ten 3-hydroxy-1-(X-phenyl)-3-phenyltriazines have been synthesized, and kinetics of their solvolysis have been measured in 40% (v/v) ethanol and sulphuric acid. The concept of kinetic acidity function has been generalized, its construction has been suggested, and the procedure has been applied to the solvolysis of 3-hydroxy-1,3-diphenyltriazenes. The kinetic acidity function found has been confronted with the H0 acidity function. The substituent effects have been evaluated with respect to mechanism of the acid catalyzed solvolysis.
New type of addition to 5-substituted 4-arylidene-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorates. Preparation of 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes
Authors: Gracza Tibor , Arnold Zdeněk , Kováč Jaroslav
Published: September 2010

4-Arilidene-5-(N,N-dimethyliminium)-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorate I undergoes a 1,4-addition reaction with organic bases under re-formation of the furan nucleus; this behaviour has been utilized in the preparation of new 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes II, III. The structure of the prepared compounds has been confirmed by 13C and 1H NMR spectra.