bluuebunny/crossref_metadata_2025 huggingface dataset:
Twisted hierarchies associated with the generalized sine-Gordon equation
Authors: Ma Hui , Wu Derchyi
Published: September 2011

Twisted U- and twisted U/K-hierarchies are soliton hierarchies introduced by Terng to find higher flows of the generalized sine-Gordon equation. Twisted \documentclass[12pt]{minimal}\begin{document}$\frac{O(J,J)}{O(J)\times O(J)}$\end{document}O(J,J)O(J)×O(J)-hierarchies are among the most important classes of twisted hierarchies. In this paper, we derive explicit interesting first and higher flows of twisted \documentclass[12pt]{minimal}\begin{document}$\frac{O(J,J)}{O(J)\times O(J)}$\end{document}O(J,J)O(J)×O(J)-hierarchies, justify that the one-dimensional systems of twisted \documentclass[12pt]{minimal}\begin{document}$\frac{O(J,J)}{O(J)\times O(J)}$\end{document}O(J,J)O(J)×O(J)-hierarchies for J = Iq, n − q(1 ⩽ q ⩽ n − 1), called the generalized sinh-Gordon equations, are the Gauss-Codazzi equations for n-dimensional timelike submanifolds with constant sectional curvature 1 and index q in pseudo-Euclidean (2n − 1)-dimensional space \documentclass[12pt]{minimal}\begin{document}$\mathbb {R}^{2n-1}_{2q-1}$\end{document}R2q−12n−1 with index 2q − 1. Furthermore, a unified treatment of the inverse scattering theory for twisted \documentclass[12pt]{minimal}\begin{document}$\frac{O(J,J)}{O(J)\times O(J)}$\end{document}O(J,J)O(J)×O(J)-hierarchies is provided.
Innovative dual function nc-SiOx:H layer leading to a >16% efficient multi-junction thin-film silicon solar cell
Authors: Yan Baojie , Yue Guozhen , Sivec Laura , Yang Jeffrey , Guha Subhendu , Jiang Chun-Sheng
Published: September 2011

We present our development of n-type nano-structured hydrogenated silicon oxide (nc-SiOx:H) as a dual-function layer in multi-junction solar cells. We optimized nc-SiOx:H and attained a conductivity suitable for a doped layer and optical property suitable for an inter-reflection layer. We tested the effectiveness of the dual-function nc-SiOx:H layer by replacing the normal n layer between the middle and the bottom cells in an a-Si:H/a-SiGe:H/nc-Si:H triple-junction structure. A significant gain in the middle cell current density of ∼1.0 mA/cm2 is achieved. We further optimized the component cells and the triple-junction structures and attained an initial active-area cell efficiency of 16.3%.
Dynamics of serrated flow in a bulk metallic glass
Authors: Ren J. L. , Chen C. , Wang G. , Mattern N. , Eckert J.
Published: September 2011

Under compression loading, bulk metallic glasses (BMGs) irreversibly deform through shear banding manifested as a serrated flow behavior. By using a statistical analysis together with a complementary dynamical analysis of the stress-time curves during serrated flow, we characterize the distinct spatiotemporal dynamical regimes and find that the plastic dynamic behavior of a Cu50Zr45Ti5 BMG changes from chaotic to self-organized critical behavior with increasing strain rate. This plastic dynamics transition with the strain rate is interpreted in the frame of the competence between the neighboring elastic strain field forming and relaxation processes.
Sleep Loss and Temporal Memory
Authors: Harrison Yvonne , Horne James A.
Published: September 2011

Historical evidence suggests that sleep deprivation affects temporal memory, but this has not been studied systematically. We explored the effects of 36 hr of sleep deprivation on a neuropsychological test of temporal memory. To promote optimal performance, the test was short, novel, and interesting, and caffeine was used to reduce “sleepiness”. A total of 40 young adults were randomized into four groups: control + caffeine (Cc), control + placebo (Cp), sleep deprived + caffeine (SDc), and sleep deprived + placebo (SDp). Controls slept normally. Caffeine (350 mg) or placebo were given just prior to testing. The task comprised colour photographs of unknown faces and had two components: recognition memory (distinction between previously presented and novel faces), and recency discrimination (temporal memory), when a previously shown face was presented. An interpolated task, self-ordered pointing, acted as a distraction. Caffeine had no effects within control conditions, but significantly reduced subjective sleepiness in SDc. Recognition was unaffected by sleep deprivation, whereas for recency, sleep deprivation groups scored significantly lower than controls. There was no significant improvement of recency with caffeine in the SDc group. Both sleep deprivation groups had poorer insight into their performance with recency. Self-ordered pointing remained unchanged. In conclusion, sleep deprivation impairs temporal memory (i.e. recency) despite other conditions promoting optimal performance.
Training Propositional Reasoning
Authors: Klauer Karl Christoph , Meiser Thorsten , Naumer Birgit
Published: September 2011

Two experiments compared the effects of four training conditions on propositional reasoning. A syntactic training demonstrated formal derivations, in an abstract semantic training the standard truth-table definitions of logical connectives were explained, and a domain-specific semantic training provided thematic contexts for the premises of the reasoning task. In a control training, an inductive reasoning task was practised. In line with the account by mental models, both kinds of semantic training were significantly more effective than the control and the syntactic training, whereas there were no significant differences between the control and the syntactic training, nor between the two kinds of semantic training. Experiment 2 replicated this pattern of effects using a different set of syntactic and domain-specific training conditions.
Feature Distribution and Background Knowledge in Category Learning
Authors: Murphy Gregory L. , Kaplan Audrey S.
Published: September 2011

Three experiments examined the interactions of category structure and prior knowledge in category learning. Experiment 1 examined the distribution of atypical or “crossover” features in category learning. In real categories, crossover features may be unevenly distributed—found primarily in very unusual examples of a category (like whales or ostriches). In contrast, in many psychology experiments, each item has exactly one crossover feature. Even versus uneven distribution of crossover features did not affect category learning when the features were neutral. However, when the features were connected by prior knowledge, it was much harder for subjects to learn the structure with the uneven distribution of crossover features. Experiments 2 and 3 found similar results with a slightly less uneven condition. We conclude that learning is a function of the interaction of category structure and prior knowledge rather than either one alone. Furthermore, knowledge benefits learning even when the category contains contradictions of the knowledge, so long as the contradictions are not very salient.
What Some Effects Might not be: The Time to Verify Membership in “Well-Defined” Categories
Authors: Larochelle Serge , Richard Solange , Souliëres Isabelle
Published: September 2011

Armstrong, Gleitman, and Gleitman (1983) reported shorter categorization times for members of well-defined categories judged more typical. They concluded that these effects could not originate in a graded, similarity-based category representation and consequently that the typicality effects obtained with natural categories might not be indicative of such a structure either. In this article, we re-examine this conclusion, focusing first on the performance obtained with well-defined categories of different sizes. Only the larger categories used showed variations in typicality ratings and produced typicality effects on categorization times. However, multiple regression analyses showed the effects on categorization times to be better explained by a measure of associative strength, called category dominance. The range of various predictor variables was equated in a follow-up experiment involving large, natural, and well-defined categories. Results obtained with well-defined categories showed pronounced dominance effects when typicality was controlled, but no reliable typicality effect when category dominance and instance familiarity were controlled. Results were opposite for natural categories. By showing that well-defined categories fail to produce unbiased typicality effects, our results bring added support to the hypothesis that the effects obtained with natural categories originate in a graded, similarity-based category structure.
Move Evaluation as a Predictor and Moderator of Success in Solutions to Well-Structured Problems
Authors: Davies Simon P.
Published: September 2011

This paper presents three studies concerned with the evaluation of moves in solutions to Tower of Hanoi problems and the effect that such evaluation processes have on solution success. The existing literature on problem solving suggests that verbalizing whilst solving a problem can have a positive effect upon performance. However, such verbalization has to be directed toward an explicit evaluation of particular moves. What remains unclear is whether evaluation without verbalization has the same effects or whether some characteristic of the process of verbalization gives rise to improved performance on such tasks. For example, the act of verbalizing per se may simply mean that more processing time is directed toward the problem-solving process. The studies reported in this paper suggest that the process of evaluation may be independent of verbalization processes and that non-verbal evaluation of moves (indicated by a key press) produces the same effects as a verbal evaluation of such moves. Moreover, the process of evaluating moves appears to produce a form of behaviour that is prone to disruption via the administration of secondary tasks, whereas non-evaluated solutions are not. This may suggest that problem solvers who engage in evaluation processes develop an explicit representation of the strategies used to solve the problem.
Surfing the Implicit Wave
Authors: Shea Charles H. , Wulf Gabriele , Whitacre Chad A. , Park Jin-Hoon
Published: September 2011

Implicit learning was investigated in two experiments involving a complex motor task. Participants were required to balance on a stabilometer and to move the platform on which they were standing to match a constantly changing target position. Experiment 1 examined whether a segment (middle third) that was repeated on each trial would be learned without participants becoming aware of the repetitions (i.e., implicitly). The purpose of Experiment 2 was to determine the relative effectiveness of explicit versus implicit learning. Here, two identical segments were presented on each trial (first and last thirds), with participants only being informed that one segment (either first or last) was repeated. The acquisition results from both experiments indicated large improvements in performance across 4 days of practice, with performance on the repeated segments being generally superior to that on the non-repeated segment. On the retention tests on Day 5, errors on the repeated segment(s) were smaller than those on the random segment(s). Furthermore, in Experiment 2, the errors on the repeated-known segment, although smaller than those on the random segment, were larger than those on the repeated-unknown segment. Interview results indicated that participants were not consciously aware that a segment was repeated unless they were informed. These results suggest that implicit learning can occur for relatively complex motor tasks and that withholding information concerning the regularities is more beneficial than providing this information.
When Insight Just Won't Come: The Failure of Visual Cues in the Nine-Dot Problem
Authors: Chronicle Edward P. , Ormerod Thomas C. , MacGregor James N.
Published: September 2011

The nine-dot problem is a classic in the field of human problem solving. Cognitive accounts of the problem's difficulty have been criticized on the grounds that the experimental methods on which they rely for support involve a qualitative change to the task requirements of the problem. The three experiments reported here utilize visual and visual-procedural hints to examine the notion that its difficulty is rooted in a mismatch between problem shape and solution shape. Experiment 1 demonstrated that a perceptual cue to the shape of the solution in the form of shading gave rise to only minimal improvements in performance; an additional hint about the relevance of the shading gave rise to modest, but not statistically significant, improvements. Experiment 2 replicated these findings against an additional control condition in which a solely verbal hint to violate the perceptual boundary of the problem shape was given. Furthermore, when both the verbal and visual hints were provided, performance improved only slightly. Experiment 3 provided participants with experience in producing the shape of the correct solution in problem variants closely related to the nine-dot problem. Performance on the transfer task, the basic nine-dot problem, remained at floor, however. These data suggest that visual constraint relaxation is unlikely to be the sole process by which the insight required to find a solution is achieved. The results are interpreted in terms of a previously proposed computational model of performance.
A comparison of upper vs. lower and right vs. left visual fields using lexical decision
Authors: Goldstein Abraham , Babkoff Harvey
Published: September 2011

A series of experiments using the lexical decision task was conducted in order to investigate the functional differences between the upper and lower visual fields (UVF, LoVF) in word recognition. Word-nonword discrimination was swifter and more accurate for word stimuli presented in the UVF. Changing the eccentricity did not affect the UVF advantage over the LoVF. UVF superiority over LoVF was found to be equivalent for both right and left visual hemifield (RVF, LVF). In general, presenting related word primes enhanced all visual field differences in a similar manner (UVF over LoVF and RVF over LVF). However, primes consisting of semantically constraining sentences enhanced the RVF advantage over the LVF, but did not affect the UVF and LoVF differentially. The argument is made that UVF superiority cannot be due to perceptual or attentional differences alone, but must also reflect top-down information flow.
The implicit benefit of learning without errors
Authors: Maxwell J.P. , Masters R.S.W. , Kerr E. , Weedon E.
Published: September 2011

Two studies examined whether the number of errors made in learning a motor skill, golf putting, differentially influences the adoption of a selective (explicit) or unselective (implicit) learning mode. Errorful learners were expected to adopt an explicit, hypothesis-testing strategy to correct errors during learning, thereby accruing a pool of verbalizable rules and exhibiting performance breakdown under dual-task conditions, characteristic of a selective mode of learning. Reducing errors during learning was predicted to minimize the involvement of explicit hypothesis testing leading to the adoption of an unselective mode of learning, distinguished by few verbalizable rules and robust performance under secondary task loading. Both studies supported these predictions. The golf putting performance of errorless learners in both studies was unaffected by the imposition of a secondary task load, whereas the performance of errorful learners deteriorated. Reducing errors during learning limited the number of error-correcting hypotheses tested by the learner, thereby reducing the contribution of explicit processing to skill acquisition. It was concluded that the reduction of errors during learning encourages the use of implicit, unselective learning processes, which confer insusceptibility to performance breakdown under distraction.
Spatial modulation of repetition blindness and repetition deafness
Authors: Soto-Faraco Salvador , Spence Charles
Published: September 2011

When two identical visual items are presented in rapid succession, people often fail to report the second instance when trying to recall both (e.g., Kanwisher, 1987). We investigated whether this temporal processing deficit is modulated by the spatial separation between the repeated stimuli within both audition and vision. In Experiment 1, lists of one to three digits were rapidly presented from loudspeaker cones arranged in a semicircle around the participant. Recall accuracy was lower when repeated digits were presented from different positions rather than from the same position, as compared to unrepeated control pairs, demonstrating that auditory repetition deafness (RD) is modulated by the spatial displacement between repeated items. A similar spatial modulation of visual repetition blindness (RB) was reported when pairs of masked letters were presented visually from either the same or different positions arranged on a semicircle around fixation (Experiment 2). These results cannot easily be accounted for by the token individuation hypothesis of RB (Kanwisher, 1987; Park & Kanwisher, 1994) and instead support a recognition failure account (Hochhaus & Johnston, 1996; Luo & Caramazza, 1995, 1996).
On a result of Brezis and Mawhin
Authors: Manásevich R. , Ward J.
Published: September 2011

Brezis and Mawhin proved the existence of at least one

T
T

periodic solution for differential equations of the form
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout 1st Row with Label left-parenthesis 0.1 right-parenthesis EndLabel left-parenthesis phi left-parenthesis u prime right-parenthesis right-parenthesis prime minus g left-parenthesis t comma u right-parenthesis equals h left-parenthesis t right-parenthesis EndLayout">

(0.1)

(
ϕ
(

u

′

)

)

′

−
g
(
t
,
u
)
=
h
(
t
)

\begin{equation}\notag (\phi (u^{\prime }))^{\prime }-g(t,u)=h(t)\tag *{(0.1)} \end{equation}

when

ϕ
:
(
−
a
,
a
)
→

R

,

\phi :(-a,a)\rightarrow \mathbb {R},

0
>
a
>
∞

0>a>\infty

, is an increasing homeomorphism with

ϕ
(
0
)
=
0

\phi (0)=0

,

g
g

is a Carathéodory function

T
T

periodic with respect to

t
t

,

2
π

2\pi

periodic with respect to

u
u

, of mean value zero with respect to

u
u

, and

h
∈

L

l
o
c

1

(

R

)

h\in L_{loc}^{1}(\mathbb {R})

is

T
T

periodic and has mean value zero. Their proof was partly variational. First it was shown that the corresponding action integral had a minimum at some point

u

0

u_{0}

in a closed convex subset

K

\mathcal {K}

of the space of

T
T

periodic Lipschitz functions. However,

u

0

u_{0}

may not be an interior point of

K

\mathcal {K}

, so it may not be a critical point of the action integral. The authors used an ingenious argument based on variational inequalities and uniqueness of a

T
T

periodic solution to (0.1) when

g
(
t
,
u
)
=
u

g(t,u)=u

to show that

u

0

u_{0}

is indeed a

T
T

periodic solution of (0.1). Here we make full use of the variational structure of the problem to obtain Brezis and Mawhin’s result.
A variable cytoplasmic domain segment is necessary for γ-protocadherin trafficking and tubulation in the endosome/lysosome pathway
Authors: O'Leary Robert , Reilly James E. , Hanson Hugo H. , Kang Semie , Lou Nicole , Phillips Greg R.
Published: September 2011

Clustered protocadherins (Pcdhs) are arranged in gene clusters (α, β, and γ) with variable and constant exons. Variable exons encode cadherin and transmembrane domains and ∼90 cytoplasmic residues. The 14 Pcdh-αs and 22 Pcdh-γs are spliced to constant exons, which, for Pcdh-γs, encode ∼120 residues of an identical cytoplasmic moiety. Pcdh-γs participate in cell–cell interactions but are prominently intracellular in vivo, and mice with disrupted Pcdh-γ genes exhibit increased neuronal cell death, suggesting nonconventional roles. Most attention in terms of Pcdh-γ intracellular interactions has focused on the constant domain. We show that the variable cytoplasmic domain (VCD) is required for trafficking and organelle tubulation in the endolysosome system. Deletion of the constant cytoplasmic domain preserved the late endosomal/lysosomal trafficking and organelle tubulation observed for the intact molecule, whereas deletion or excision of the VCD or replacement of the Pcdh-γA3 cytoplasmic domain with that from Pcdh-α1 or N-cadherin dramatically altered trafficking. Truncations or internal deletions within the VCD defined a 26–amino acid segment required for trafficking and tubulation in the endolysosomal pathway. This active VCD segment contains residues that are conserved in Pcdh-γA and Pcdh-γB subfamilies. Thus the VCDs of Pcdh-γs mediate interactions critical for Pcdh-γ trafficking.
Widespread Occurrence and Diversity of Cassava brown streak virus (Potyviridae: Ipomovirus) in Tanzania
Authors: Rwegasira G. M. , Momanyi G. , Rey M. E. C. , Kahwa G. , Legg J. P.
Published: September 2011

Cassava brown streak disease (CBSD) has been a problem in Tanzania since 1936. Existing literature indicated limited distribution of the disease to low altitudes, usually <100 m above sea level, but the current geographical distribution of the disease was not known. Whether a single or many strains for the virus exist in Tanzania had not been reported to date. In this study, CBSD was recorded from sea level to ≈1,800 m above sea level. In total, 2,730 cassava plants were assessed for CBSD leaf symptoms in 91 fields and root symptoms were assessed at 81 sites. A sample was taken from each site for laboratory screening for Cassava brown streak virus (CBSV). CBSD mean foliar and root incidences were 38 and 36%, respectively. Reverse-transcription polymerase chain reaction of a partial 3′-terminal coat protein (CP) region of CBSV indicated the presence of CBSV in 67 of the 91 (73%) samples. Forty-three amplicons were sequenced, and phylogenetic comparisons with nucleotide sequences from GenBank (National Center for Biotechnology Information database) suggested that one major clade of CBSV primarily exists in Tanzania. However, there was nucleotide sequence divergence of up to 19% among the 42 isolates. In all, 42 of the 43 sequences had 80 to 100% nucleotide identity with 6 previously reported CP-CBSV sequences (from Mozambique and Tanzania). In total, 13 of 42 isolates had <80% nucleotide identities with three previously reported Ugandan CBSV sequences. One isolate, FJ687177, shared <78% sequence identity with the other Tanzanian sequences but was closely related (93%) to Ugandan isolates. It is likely that isolate FJ687177 may belong to a less widely distributed recently described species (clade 2) of CBSV, named Ugandan cassava brown streak virus (UCBSV).
Repetitive prime-and-realign mechanism converts short capped RNA leaders into longer ones that may be more suitable for elongation during rice stripe virus transcription initiation
Authors: Yao Min , Zhang Tianqi , Zhou Tong , Zhou Yijun , Zhou Xueping , Tao Xiaorong
Published: September 2011

Cucumber mosaic virus (CMV) RNAs were found to serve as cap donors for rice stripe virus (RSV) transcription initiation during their co-infection of Nicotiana benthamiana. The 5′ end of CMV RNAs was cleaved preferentially at residues that had multiple-base complementarity to the 3′ end of the RSV template. The length requirement for CMV capped primers to be suitable for elongation varied between 12 and 20 nt, and those of 12–16 nt were optimal for elongation and generated more CMV–RSV chimeric mRNA transcripts. The original cap donors that were cleaved from CMV RNAs were predominantly short (10–13 nt). However, the CMV capped RNA leaders that underwent long-distance elongation were found to contain up to five repetitions of additional AC dinucleotides. Sequence analysis revealed that these AC dinucleotides were used to increase the size of short cap donors in multiple prime-and-realign cycles. Each prime-and-realign cycle added an AC dinucleotide onto the capped RNA leaders; thus, the original cap donors were gradually converted to longer capped RNA leaders (of 12–20 nt). Interestingly, the original 10 nt (or 11 nt) cap donor cleaved from CMV RNA1/2 did not undergo direct extension; only capped RNA leaders that had been increased to ≥12 nt were used for direct elongation. These findings suggest that this repetitive priming and realignment may serve to convert short capped CMV RNA leaders into longer, more suitable sizes to render a more stabilized transcription complex for elongation during RSV transcription initiation.
New insights into RNA packaging in porcine reproductive and respiratory syndrome virus
Authors: Baig Tayyba T. , Zakhartchouk Alexander
Published: September 2011

While identifying whether the smallest packaged heteroclite subgenomic RNA (S9) of porcine reproductive and respiratory syndrome virus (PRRSV) contains a packaging signal, we found that S9 was capable of binding to the basic amino acid-rich domain (synthetic peptide of aa 34–53) of the packaging protein (N). In addition, by using truncations at the 5′ and 3′ ends of S9, a minimal binding region of 35 nt was found to be essential for binding to both the synthetic peptide and to the full-length N protein. Furthermore, by using cell-culture experiments, we found that S9 was capable of packaging non-viral RNA sequence into PRRSV particles and that the 35 nt region was essential for this activity. Taken together, our data suggest that this 35 nt region might be an important element for packaging PRRSV genomic RNA into virus particles.
Accessibility of the coxsackievirus and adenovirus receptor and its importance in adenovirus gene transduction efficiency
Authors: Sharma Priyanka , Kolawole Abimbola Olayinka , Wiltshire Sydney Marie , Frondorf Kathleen , Excoffon Katherine Julie Diane Ashbourne
Published: September 2011

Viruses are commonly investigated as vector systems for gene therapy. To be effective, virus-mediated gene-delivery systems require the presence of specific virus receptors to enter the target cell. One example is adenovirus and its primary receptor is the coxsackievirus and adenovirus receptor (CAR). Madin–Darby canine kidney (MDCK) cells have become a choice model system for studying CAR and adenovirus infection due to their ability to polarize rapidly into an epithelium with high transepithelial resistance. We show here that, whilst MDCK cells are resistant to adenovirus infection and hence appear functionally CAR-deficient, polarized MDCK cells express significant levels of CAR sequestered on the basolateral surface, where it is inaccessible for virus infection. Thus, although a cell type may be resistant to adenovirus infection, it is impossible to know whether it is due to a deficiency, as both CAR absence and inaccessibility are barriers to adenovirus-mediated gene transfer.
Identification of groupers based on pyloric caeca differentiation
Authors: Roy T. S. C. , Gopalakrishnan A.
Published: September 2011

The examination of nine species of groupers present in south‐east Indian waters has indicated that the pyloric caeca number, pattern and colouration are reliable and useful characters for identification. Three distinct morphotypes of pyloric caeca were observed in this study.
Insulin‐like growth factor II mRNA‐binding protein 3 expression predicts unfavorable prognosis in patients with neuroblastoma
Authors: Chen Szu‐Ta , Jeng Yung‐Ming , Chang Cheng‐Chi , Chang Hsiu‐Hao , Huang Min‐Chuan , Juan Hsueh‐Fen , Hsu Chun‐Hua , Lee Hsinyu , Liao Yung‐Feng , Lee Ya‐Ling , Hsu Wen‐Ming , Lai Hong‐Shiee
Published: September 2011

Insulin‐like growth factor II mRNA‐binding protein 3 (IMP3) has been reported to enhance proliferation and invasion in various cancers. The role of IMP3 on neuroblastoma (NB) is unknown. We aimed to clarify the prognostic significance of IMP3 expression in patients with NB. By microarray analysis, high IMP3 expression was found in patients with poor outcome. IMP3 expression in 90 NB samples was analyzed by immunohistochemical staining to correlate with clinical stages, histology, and patient outcome. Positive IMP3 expression was detected in 52 of 90 patients, and was significantly correlated with undifferentiated histology, advanced stages, MYCN amplification, and poor outcome. In subgroups, positive IMP3 expression could predict an even worse prognosis in patients with advanced disease, with normal MYCN status, or with MYCN amplification (P = 0.005, P = 0.001, and P = 0.033, respectively). The IMP3 expression decreased by induction of differentiation with retinoid acid treatment in SK‐N‐DZ and SK‐N‐SH cells in vitro. The invasion ability of NB cells also decreased as IMP3 knockdown by using RNA interference in vitro. In summary, high expression of IMP3 in NB might contribute to the undifferentiated phenotype and invasive behaviors, leading to a poor prognosis. Determining IMP3 expression in NB could help to improve a personalized therapy. (Cancer Sci 2011; 102: 2191–2198)
The effect of hepatitis C treatment and human immunodeficiency virus (HIV) co‐infection on the disease burden of hepatitis C among injecting drug users in Amsterdam
Authors: Matser Amy , Urbanus Anouk , Geskus Ronald , Kretzschmar Mirjam , Xiridou Maria , Buster Marcel , Coutinho Roel , Prins Maria
Published: September 2011

Aims  The hepatitis C virus (HCV) disease burden among injecting drug users (IDUs) is determined by HCV incidence, the long latency period of HCV, competing mortality causes, presence of co‐infection and HCV treatment uptake. We examined the effect of these factors and estimated the HCV disease burden in Amsterdam.

Design  A Markov model was developed, incorporating HCV and human immunodeficiency virus (HIV), and parameterized with data from the Amsterdam Cohort Studies, surveillance studies and literature.

Setting  IDU population of Amsterdam.

Measurements  HCV infection simulated from its acute phase to HCV‐related liver disease (i.e. decompensated cirrhosis and hepatocellular carcinoma).

Findings  The HCV prevalence among IDUs in Amsterdam increased to approximately 80% in the 1980s. From 2011 to 2025, the HCV‐related disease prevalence will accordingly rise by 36%, from 57 cases (95% range 33–94) to 78 (95% range 43–138), respectively. In total, 945 (95% range 617–1309) individuals will develop HCV‐related liver disease. This burden would have been 33% higher in the absence of HIV, resulting in 1219 cases (95% range 796–1663). In Amsterdam, 25% of HIV‐negative IDUs receive successful HCV treatment, reducing the cumulative disease burden by 14% to 810 (95% range 520–1120). Further reduction of 36% can be achieved by improving treatment, resulting in 603 cases (95% range 384–851).

Conclusions  The hepatitis C virus burden among injecting drug users in Amsterdam has been reduced by a high competing mortality rate, particularly caused by HIV infection, and to a smaller extent by hepatitis C virus treatment. Improved hepatitis C virus treatment is expected to contribute to reduce the future hepatitis C virus disease burden.
Revisiting the quantitative trait loci for milk production traits on BTA6
Authors: Weikard R. , Widmann P. , Buitkamp J. , Emmerling R. , Kuehn C.
Published: September 2011

A parallel association study was performed in two independent cattle populations based on 41 validated, targeted single nucleotide polymorphisms (SNPs) and four microsatellite markers to re‐evaluate the multiple quantitative trait loci (QTL) architecture for milk performance on bovine chromosome 6 (BTA6). Two distinct QTL located in the vicinity of the middle region of BTA6, but differing unambiguously regarding their effects on milk composition and yield traits were validated in the German Holstein population. A highly significant association of the protein variant ABCG2 p.Tyr581Ser with milk composition traits reconfirmed the causative molecular relevance of the ABCG2 gene in QTL region 1, whereas in QTL region 2, significant and tentative associations between gene variants RW070 and RW023 (located in the promoter region and exon 9 of the PPARGC1A gene for milk yield traits) were detected. For the German Fleckvieh population, only RW023 showed a tentative association with milk yield traits, whereas those loci with significant effects in German Holsteins (ABCG2 p.Tyr581Ser, RW070) showed fixed alleles. Even though our new data highlight two variants in the PPARGC1A gene (RW023, RW070) in QTL region 2, based on the results of our study, currently no unequivocal conclusion about the causal background of this QTL affecting milk yield traits can be drawn. Notably, the German Holstein and Fleckvieh populations, known for their divergent degree of dairy type, differ substantially in their allele frequencies for the growth‐associated NCAPG p.Ile442Met locus.
Parent views of the positive contributions of elementary and high school‐aged children with autism spectrum disorders and Down syndrome
Authors: King G. , Zwaigenbaum L. , Bates A. , Baxter D. , Rosenbaum P.
Published: September 2011

Background  Much is known about the hardships associated with parenting a child with a disability, but few studies have examined the broader contributions of the child to family life or society.

Methods  The study involved qualitative analysis of interviews with 16 families of children with autism spectrum disorder or Down syndrome at critical transition periods (entry to elementary or high school), targeting their perceptions of benefits.

Results  Parents discussed a wide range of benefits beyond the personal level, including parental, family and societal benefits. Exploratory group comparisons indicated that parents of high school‐aged children were more likely to mention family‐level and societal benefits.

Conclusions  The findings suggest that raising a child with a disability can trigger role‐related decisions that lead to a series of resiliency‐related processes and cascading benefits. The findings inform practitioners about the nature of potential positive experiences that can be shared with families starting out on their journey, allowing parents to recognize the positive dimensions of raising a child with a disability in addition to the hardships.
Nurses’ perception of time availability in patient communication in Hong Kong
Authors: Chan Engle A , Jones Aled , Fung Sylvia , Wu Sui Chu
Published: September 2011

Aims.  To explore nurses’ perceptions of their patient communication in practice and to identify their ways of communicating.

Background.  Nurse theorists and clinicians are aware of the importance of nurse–patient communication in providing patient‐centred care. However, barriers remain that prevent nurses from implementing quality/effective communication, and time is often viewed as a critical variable. Continuous emphasis on efficiency contravenes patient‐centred care, warranting a re‐examination of nurses’ perception of time in nurse–patient communication.

Design.  Focus group interviews were adopted. Thirty‐nine registered nurses participated. Interviews were tape‐recorded, transcribed and translated, and data were analysed using thematic analysis to identify codes, categories and themes/patterns.

Results.  Three themes were identified regarding nurses’ perception of communication with time: (1) Patterns of communication. (2) Routine scheduled communication vs. meeting individuals’ needs. (3) Saving time through communication. Patterns of communication, based on participants’ criteria such as the purpose, who initiated it, the nature of communication, expectation to perform, therapeutic value and relation with time were explicated. By integrating communication into routines as intended actions, nurses demonstrate that communication and relationship building with patients take no extra time. Good communication and good relationships help nurses save time.

Conclusions.  Nurses’ communication behaviour is closely related to their perception of communication. This study suggests the need for a paradigm shift in thinking about communication as requiring time. Additionally, nurses should recognise the value of short, iterative interaction and chit‐chat as quality communication for knowing their patients and providing patient‐centred care.

Relevance to clinical practice.  Nurses should think beyond time in the discourse of effective nurse–patient communication, as it often relates to manpower. An understanding of how nurses perceive their time availability for nurse–patient communication and their use of time for this aspect contribute to the discourse regarding how to improve patient‐centred care.
Empirical evaluation of directed dispersal and density‐dependent effects across successive recruitment phases
Authors: Spiegel Orr , Nathan Ran
Published: September 2011

1. The directed‐dispersal (DrD) hypothesis constitutes one of the main explanations for the adaptive value of seed dispersal in spatially heterogeneous environments. Traditionally, the DrD hypothesis asserts non‐random arrival to specific sites where establishment conditions are independently favourable. Yet, enhanced arrival might negatively affect the establishment in otherwise favourable sites through enhanced density‐dependent mortality (DDM). Since both density effects and habitat suitability might differ among establishment phases, assessment of habitat suitability should encompass the entire establishment process.

2. Here, we test the DrD hypothesis against a null model of random dispersal (RD) in an arid ecosystem where fleshy‐fruited perennial Ochradenus baccatus shrubs are dispersed by two resident passerines. Acacia trees were predicted to present the favourable habitat in our system through the nurse‐plant effect facilitating O. baccatus early establishment.

3. We determined expected seed arrival by monitoring the dispersers’ time allocation among the different habitats and assessed habitat quality for different establishment phases: seed‐phase survival (post‐dispersal survival and germination) was determined by line transects, while early seedling survival was estimated by monitoring seedlings throughout the first dry season. Additionally, subsequent recruitment success was assessed by comparing the distribution of adult shrubs to that expected from the observed germination patterns.

4. When considering the expected seed arrival and early establishment (seed‐phase and early seedling survival), the DrD hypothesis is supported: birds preferentially deposited seeds in habitats where conditions are favourable (e.g. under Acacia trees). Yet, considering recruitment success during later phases, the dispersal service provided by the birds was less beneficial than RD.

5. Effective density was indexed using the zone‐of‐influence approach in which densities are corrected by phase‐specific sizes. We suggest that intense seed deposition into favourable habitats has led to strong DDM (presumably through competition) in those habitats during late establishment phases and was responsible, at least partially, for changes in habitat suitability across the recruitment phases.

6. Synthesis. Our results show that assessment of the DrD hypothesis depends on the context of the study (in terms of recruitment phases) since sites of enhanced seed arrival and high seed‐to‐seedling survival can ultimately prove unfavourable to the plant if density‐dependent or other effects might increase mortality in these sites during later recruitment phases.
454‐sequencing reveals stochastic local reassembly and high disturbance tolerance within arbuscular mycorrhizal fungal communities
Authors: Lekberg Ylva , Schnoor Tim , Kjøller Rasmus , Gibbons Sean M. , Hansen Lars H. , Al‐Soud Waleed A. , Sørensen Søren J. , Rosendahl Søren
Published: September 2011

1. Disturbance is assumed to be a major driver of plant community composition, but whether similar processes operate on associated soil microbial communities is less known. Based on the assumed trade‐off between disturbance tolerance and competiveness, we hypothesize that a severe disturbance applied within a semi‐natural grassland would shift the arbuscular mycorrhizal (AM) fungal community towards disturbance‐tolerant fungi that are rare in undisturbed soils.

2. We used 454‐sequencing of the large subunit rDNA region to characterize AM fungal communities in Plantago lanceolata roots grown in the field for 4 months and exposed either to no disturbance or to severe disturbance where fungi from undisturbed soil were either permitted or prevented from re‐colonizing the disturbed area. This allowed for a distinction between AM fungi that survived the disturbance and those that quickly re‐colonized after a disturbance. To identify AM fungi that could potentially colonize the experimental plants, we also analysed roots from adjacent, undisturbed vegetation.

3. We found 32 fungal operational taxonomic units (OTUs) distributed across five known AM fungal families. Contrary to our expectations, disturbance did not significantly alter the community composition and OTU richness. Instead, OTU abundances were positively correlated across treatments; i.e., common OTUs in undisturbed soil were also common after the severe disturbance. However, the distribution of OTUs within and between plots was largely unpredictable, with approximately 40% of all sequences within a sample belonging to a single OTU of varying identity. The distribution of two plant species that are often poorly colonized by AM fungi (Dianthus deltoides and Carex arenaria) correlated significantly with the OTU composition, which may indicate that host quality could be an additional driver of fungal communities.

4. Synthesis. Our results suggest that factors other than disturbance drive the relative abundance of OTUs in this grassland and question the long‐held assumption that communities shift in a predictable manner after a disturbance event. The reassembly of this fungal community indicates a high community resilience, but substantial local stochasticity and dominance by single OTUs, which could be due to priority effects among abundant AM fungi possessing a similar – and high – degree of disturbance tolerance.
Establishment, characterization and viral susceptibility of a new cell line derived from goldfish, Carassius auratus (L.), tail fin
Authors: Yan W , Nie P , Lu Y
Published: September 2011

A continuous cell line [goldfish tail fin (GFTF)] derived from a goldfish tail fin, Carassius auratus, was established and characterized. GFTF cells predominantly consist of fibroblast‐like cells that were maintained and subcultured more than 50 times over a period of 15 months. Cells grew at temperatures between 15 and 37°C, with an optimum temperature of 25°C. The growth rate of GFTF cells increased proportionally with the foetal bovine serum (FBS) concentration (5–20%), with optimum growth at 20% FBS. The chromosome numbers were 88–112, with a modal peak of 104 chromosomes. Five known fish viruses were tested to determine susceptibility. Results demonstrated that GFTF is susceptible to snakehead rhabdovirus, spring viraemia of carp virus and channel catfish virus (CCV). In addition, GFTF demonstrated a higher sensitivity to, and increased viral production of, CCV than that observed in the control cell line, channel catfish ovary cells. This suggests that GFTF cells would be useful as a diagnostic tool for viral diseases in this fish species, as well as for the isolation and study of goldfish viruses in the future. Furthermore, these cells were transfected with pEGFP‐N1 vector DNA and some fluorescent signals were observed, suggesting that GFTF cells could be a useful tool for transgenic and genetic manipulation studies.
Brief report: Impact of applied behaviour analysis (ABA) on carer burden and community participation in challenging behaviour: results from a randomised controlled trial
Authors: Hassiotis A. , Robotham D. , Canagasabey A. , Marston L. , Thomas B. , King M.
Published: September 2011

Background  Applied behaviour analysis (ABA) reduces challenging behaviour in people with intellectual disability. There is interest, however, in whether such interventions reduce carer burden and increase community participation in this group.

Methods  A 6‐month randomised controlled trial was followed by a longer‐term naturalistic follow‐up of participants. We studied the impact of the challenging behaviour on the carers and on the daily activities of the participants measured by the Carer Uplift and Burden Scale and Guernsey Community Participation and Leisure Assessment respectively.

Results  Both community participation and carer burden improved at 6 and 24 months. Burden showed significant reduction in family carers compared with paid carers. There was no significant intervention effect on the variables under consideration.

Conclusions  ABA appears to be no more effective than standard care in improving social outcomes in people with intellectual disabilities and challenging behaviour but this requires further examination in a larger trial.
A computer‐based interactive multimedia program to reduce HIV transmission for women with intellectual disability
Authors: Wells J. , Clark K. D. , Sarno K.
Published: September 2011

Background  Despite recent recognition of the need for preventive sexual health materials for people with intellectual disability (ID), there have been remarkably few health‐based interventions designed for people with mild to moderate ID. The purpose of this study was to evaluate the effects of a computer‐based interactive multimedia (CBIM) program to teach HIV/AIDS knowledge, skills and decision making.

Methods  Twenty‐five women with mild to moderate ID evaluated the program. The study used a quasi‐experimental within‐subjects design to assess the efficacy of the CBIM program. Research participants completed five qualitative and quantitative instruments that assessed HIV knowledge, and decision‐making skills regarding HIV prevention practices and condom application skills (i.e. demonstration of skills opening a condom and putting it on a model penis). In addition, 18 service providers who work with women with ID reviewed the program and completed a demographics questionnaire and a professional customer satisfaction survey.

Results  Women with ID showed statistically significant increases from pre‐test to post‐test in all knowledge and skill domains. Furthermore, the statistical gains were accompanied by medium to large effect sizes. Overall, service providers rated the program highly on several outcome measures (stimulation, relevance and usability).

Conclusions  The results of this study indicate the CBIM program was effective in increasing HIV/AIDS knowledge and skills among women with ID, who live both semi‐independently and independently, in a single‐session intervention. As the CBIM program is not dependent on staff for instructional delivery, it is a highly efficient teaching tool; and CBIM is an efficacious means to provide behavioural health content, compensating for the dearth of available health promotion materials for people with ID. As such, it has a potential for broad distribution and implementation by medical practitioners, and public health offices. People with ID are part of our society, yet continue to be overlooked, particularly in the area of health promotion. Special tools need to be developed in order to address the health disparities experienced by people with ID.