bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased nutritive value of transgenic potato by expressing a nonallergenic seed albumin gene fromAmaranthus hypochondriacus
Authors: Chakraborty Subhra , Chakraborty Niranjan , Datta Asis
Published: July 2012

Improvement of nutritive value of crop plants, in particular the amino acid composition, has been a major long-term goal of plant breeding programs. Toward this end, we reported earlier the cloning of the seed albumin geneAmA1fromAmaranthus hypochondriacus. The AmA1 protein is nonallergenic in nature and is rich in all essential amino acids, and the composition corresponds well with the World Health Organization standards for optimal human nutrition. In an attempt to improve the nutritional value of potato, theAmA1coding sequence was successfully introduced and expressed in tuber-specific and constitutive manner. There was a striking increase in the growth and production of tubers in transgenic populations and also of the total protein content with an increase in most essential amino acids. The expressed protein was localized in the cytoplasm as well as in the vacuole of transgenic tubers. Thus we have been able to use a seed albumin gene with a well-balanced amino acid composition as a donor protein to develop a transgenic crop plant. The results document, in addition to successful nutritional improvement of potato tubers, the feasibility of genetically modifying other crop plants with novel seed protein composition.
Light stress-regulated two-helix proteins in
Arabidopsis thaliana
related to the chlorophyll
a/b
-binding gene family
Authors: Heddad Mounia , Adamska Iwona
Published: July 2012

The chlorophyll
a/b
, chlorophyll
a/c
, and chlorophyll
a/a
light-harvesting proteins are part of an extended gene family that also includes the transiently expressed stress proteins, the Elips (early light-induced proteins). Four Elip homologue proteins, encoded by single-copy nuclear genes, have been identified in the
Arabidopsis thaliana
database. These proteins were divided into two groups according to the expression pattern under light-stress conditions and the predicted secondary structure. Group one included two members of the Elip family with three predicted transmembrane helices and a gene expression strictly related to light stress. Group two included two proteins, the Seps (stress-enhanced proteins), which possessed two predicted transmembrane segments. The transcripts of Sep1 and Sep2 were present under low light conditions, but their level increased 4- to 10-fold during illumination of plants with high-intensity light. Preliminary data indicated that the induced transcripts were translated
in vivo
. Other physiological stress conditions, such as cold, heat, desiccation, salt, wounding, or oxidative stress, did not significantly influence the expression of
Sep
genes.
In vitro
import of radioactively labeled precursors of Seps into isolated chloroplasts confirmed the thylakoid membrane localization of these proteins. Considering the predicted protein structure and homology to other pigment-antenna proteins, the two-helix Seps might represent an evolutionary missing link between the one- and three-helix antenna proteins present in pro- and eukaryota.
The molecular basis of vernalization: The central role of
FLOWERING LOCUS C
(
FLC
)
Authors: Sheldon Candice C. , Rouse Dean T. , Finnegan E. Jean , Peacock W. James , Dennis Elizabeth S.
Published: July 2012

In
Arabidopsis
, the MADS-box protein encoded by
FLOWERING LOCUS C
(
FLC
) is a repressor of flowering. Vernalization, which promotes flowering in the late-flowering ecotypes and many late-flowering mutants, decreases the level of
FLC
transcript and protein in the plant. This vernalization-induced reduction in
FLC
transcript levels is mitotically stable and occurs in all tissues.
FLC
activity is restored in each generation, as is the requirement of a low-temperature exposure for the promotion of flowering. The level of
FLC
determines the extent of the vernalization response in the promotion of flowering, and there is a quantitative relationship between the duration of cold treatment and the extent of down-regulation of
FLC
activity. We conclude that
FLC
is the central regulator of the induction of flowering by vernalization. Other vernalization-responsive late-flowering mutants, which are disrupted in genes that encode regulators of
FLC
, are late-flowering as a consequence of their elevated levels of
FLC
.
The integral membrane
S
-locus receptor kinase of
Brassica
has serine/threonine kinase activity in a membranous environment and spontaneously forms oligomers
in planta
Authors: Giranton Jean-Loïc , Dumas Christian , Cock J. Mark , Gaude Thierry
Published: July 2012

To gain further insight into the mode of action of
S
-locus receptor kinase (SRK), a receptor-like kinase involved in the self-incompatibility response in
Brassica
, different recombinant SRK proteins have been expressed in a membranous environment using the insect cell/baculovirus system. Recombinant SRK proteins exhibited properties close to those of the endogenous stigmatic SRK protein and were found to autophosphorylate on serine and threonine residues in insect cell microsomes. Autophosphorylation was constitutive because it did not require the presence of pollen or stigma extracts in the phosphorylation buffer. Phosphorylation was shown to occur in
trans
, suggesting the existence of constitutive homooligomers of membrane-anchored recombinant SRK. To investigate the physiological relevance of these results, we have examined the oligomeric status of SRK
in planta
in cross-linking experiments and by velocity sedimentation on sucrose gradients. Our data strongly suggest that SRK is associated both with other SRK molecules and other stigma proteins in nonpollinated flowers. These findings may have important implications for our understanding of self-pollen signaling.
Isolation and characterization of pollen coat proteins of
Brassica campestris
that interact with
S
locus-related glycoprotein 1 involved in pollen–stigma adhesion
Authors: Takayama Seiji , Shiba Hiroshi , Iwano Megumi , Asano Kosuke , Hara Minoru , Che Fang-Sik , Watanabe Masao , Hinata Kokichi , Isogai Akira
Published: July 2012

Adhesion of pollen grains to the stigmatic surface is a critical step during sexual reproduction in plants. In
Brassica
,
S
locus-related glycoprotein 1 (SLR1), a stigma-specific protein belonging to the
S
gene family of proteins, has been shown to be involved in this step. However, the identity of the interacting counterpart in pollen and the molecular mechanism of this interaction have not been determined. Using an optical biosensor immobilized with
S
gene family proteins, we detected strong SLR1-binding activity in pollen coat extracts of
Brassica campestris
. Two SLR1-binding proteins, named SLR1-BP1 and SLR1-BP2, were identified and purified by the combination of SLR1 affinity column chromatography and reverse-phase HPLC. Sequence analyses revealed that these two proteins (
i
) differ only in that a proline residue near the N terminus is hydroxylated in SLR1-BP1 but not in SLR1-BP2, and (
ii
) are members of the class A pollen coat protein (PCP) family, which includes PCP-A1, an SLG (
S
locus glycoprotein)-binding protein isolated from
Brassica oleracea
. Kinetic analysis showed that SLR1-BP1 and SLR1-BP2 specifically bound SLR1 with high affinity (
K
d
= 5.6 and 4.4 nM, respectively). The
SLR1-BP
gene was specifically expressed in pollen at late stages of development, and its sequence is highly conserved in
Brassica
species with the A genome.
Reliability and validity of the 7‐day Physical Activity Recall interview in a Spanish population
Authors: Zuazagoitia Ana , Montoya Imanol , Grandes Gonzalo , Arietaleanizbeascoa Ma Soledad , Arce Veronica , Martinez Vicente , Sanchez Mairena , Sanchez Alvaro
Published: July 2012

The aim of this study was to assess the reliability and convergent validity of the 7‐day Physical Activity Recall (7‐day PAR) interview in a sample of the Spanish population. Valid 7‐day PAR interviews were conducted and RT3 accelerometer measurements taken for 160 subjects from the primary care population aged 24–83, 75 men and 85 women. Two 7‐day PAR interviews were conducted, with a one‐week interval, with 147 of these participants. Test–retest reliability was assessed using intraclass correlation coefficients. Convergent validity between the 7‐day PAR and the accelerometer data were examined using Spearman's correlation coefficients, and the kappa index of agreement was calculated. The 7‐day PAR reliability coefficients were 0.68 (95%CI: 0.58–0.76) for total energy expenditure, 0.65 (95%CI: 0.54–0.73) for the activity dose, and 0.61 (95%CI: 0.50–0.70) and 0.75 (95%CI: 0.67–0.81) for time spent on moderate and vigorous‐intensity activity, respectively. These coefficients ranged from 0.91 to 0.96 in participants who reported a typical week in both interviews. Convergent validity ranged from 0.25 for time spent on vigorous activity to 0.52 for the activity dose, and the kappa index was 0.43 (95%CI: 0.30–0.56). Reliability and convergent validity coefficients in the Spanish population were generally moderate and similar to those found in other studies.
Considering long‐term sustainability in the development of world class success
Authors: Güllich Arne , Emrich Eike
Published: July 2012

The developmental practice patterns leading to the highest levels of success remain a subject of debate. The present study purposes to extend the body of empirical research by analysing athletic biographies from a large sample of German national squad athletes across all Olympic sports (n=1558; 57% male, 43% female). In a combined retrospective and longitudinal study utilising postal questionnaires, we evaluated the age at onset, volume, domain‐specificity, variability in training and competition and success attained at different ages. Developmental practice patterns leading to rapid adolescent success and long‐term senior success were inconsistent, and in some aspects contradictory. An early start‐age for training and competition, early specialisation, high‐intensity specific practice in the respective domain sport and little or no involvement in other sports (OS) favoured early adolescent success. Juvenile success, however, did not contribute to individual differences in success achieved at a senior age (−0.09<r s <0.03). Senior world class performers differed from national class athletes in a later age for onset of training and competition in their domain sport, later specialisation (14.4 vs. 12.1 years), more involvement in OS (training 66% vs. 51%; competitions 53% vs. 39%), but not in practice volume in their domain sport at any age. Findings were confirmed with longitudinal testing and were widely consistent across types of sports. These findings are interpreted relative to correspondence to deliberate practice and DMSP frameworks while drawing on the concept of long‐term sustainability.
Imposed-dynamo current drive
Authors: Jarboe T.R. , Victor B.S. , Nelson B.A. , Hansen C.J. , Akcay C. , Ennis D.A. , Hicks N.K. , Hossack A.C. , Marklin G.J. , Smith R.J.
Published: July 2012

A mechanism for steady inductive helicity injection (SIHI) current drive has been discovered where the current driving fluctuations are not generated by the plasma but rather are imposed by the injectors. Sheared flow of the electron fluid distorts the imposed fluctuations to drive current. The model accurately predicts the time dependent toroidal current, the injector impedance scaling, and the profile produced in the HIT-SI experiment. These results show that a stable equilibrium can be efficiently sustained with imposed fluctuations and the current profile can, in principle, be controlled. Both are large steps for controlled fusion. Some of the effects of the fluctuations on the confinement of tokamak and spheromak reactors are assessed and the degradation may be tolerable. The mechanism is also of interest to plasma self-organization, fast reconnection and plasma physics in general.
Critical cones of characteristic varieties
Authors: Boldini Roberto
Published: July 2012

Let

M
M

be a left module over a Weyl algebra in characteristic zero. Given natural weight vectors

ν
\nu

and

ω
\omega

, we show that the characteristic varieties arising from filtrations with weight vector

ν
+
s
ω

\nu +s\omega

stabilize to a certain variety determined by

M
M

,

ν
\nu

,

ω
\omega

as soon as the natural number

s
s

grows beyond a bound which depends only on

M
M

and

ν
\nu

but not on

ω
\omega

.

As a consequence, in the notable case when

ν
\nu

is the standard weight vector, these characteristic varieties deform to the critical cone of the

ω
\omega

-characteristic variety of

M
M

as soon as

s
s

grows beyond an invariant of

M
M

.

As an application, we give a new, easy, non-homological proof of a classical result, namely, that the

ω
\omega

-characteristic varieties of

M
M

all have the same Krull dimension.

The set of all

ω
\omega

-characteristic varieties of

M
M

is finite. We provide an upper bound for its cardinality in terms of supports of universal Gröbner bases in the case when

M
M

is cyclic. By the above stability result, we conjecture a second upper bound in terms of total degrees of universal Gröbner bases and of Fibonacci numbers in the case when

M
M

is cyclic over the first Weyl algebra.
Complex symmetric weighted shifts
Authors: Zhu Sen , Li Chun
Published: July 2012

An operator

T
T

on a complex Hilbert space

H

\mathcal {H}

is said to be complex symmetric if there exists a conjugate-linear, isometric involution

C
:

H

⟶

H

C:\mathcal {H}\longrightarrow \mathcal {H}

so that

C
T
C
=

T
∗

CTC=T^*

. In this paper, it is completely determined when a scalar (unilateral or bilateral) weighted shift is complex symmetric. In particular, we give a canonical decomposition of weighted shifts with complex symmetry. Also we characterize those weighted shifts for which complex symmetry is invariant under generalized Aluthge transforms. As an application, we give a negative answer to a question of S. Garcia.
Large G3BP-induced granules trigger eIF2α phosphorylation
Authors: Reineke Lucas C. , Dougherty Jon D. , Pierre Philippe , Lloyd Richard E.
Published: July 2012

Stress granules are large messenger ribonucleoprotein (mRNP) aggregates composed of translation initiation factors and mRNAs that appear when the cell encounters various stressors. Current dogma indicates that stress granules function as inert storage depots for translationally silenced mRNPs until the cell signals for renewed translation and stress granule disassembly. We used RasGAP SH3-binding protein (G3BP) overexpression to induce stress granules and study their assembly process and signaling to the translation apparatus. We found that assembly of large G3BP-induced stress granules, but not small granules, precedes phosphorylation of eIF2α. Using mouse embryonic fibroblasts depleted for individual eukaryotic initiation factor 2α (eIF2α) kinases, we identified protein kinase R as the principal kinase that mediates eIF2α phosphorylation by large G3BP-induced granules. These data indicate that increasing stress granule size is associated with a threshold or switch that must be triggered in order for eIF2α phosphorylation and subsequent translational repression to occur. Furthermore, these data suggest that stress granules are active in signaling to the translational machinery and may be important regulators of the innate immune response.
The Theoretical Community (Or, Is There a Theory in this Journal?)
Authors: Hass Andrew W.
Published: July 2012

The following essay explores the nature of theory within the interdisciplinary space we call literature and theology—or more generally religion and literature—and the role theory has played in that space’s collective practice. It argues that theory is natural to the ‘binding’ of religion with literature and of literature with religion, since both are caught in a dilemma of reading, including the ‘reading’ of the practices that mark each of their respective disciplines. The discussion then looks at the spectatorial nature of the ancient notion of theory as theoria, before it traces how theory, in moving from theoria to high Theory, has figured in the 25 volumes of Literature and Theology itself. This tracing covers a double assumption of theory and an appropriation of the ‘other’ as theory. The essay concludes by looking at the dynamic that continues to bind literature and theology, and indeed the readers of a journal such as this one, in a communality of theory, practice, and interpretation.
What Factors Affect Intrapartum Maternal Temperature? A Prospective Cohort Study
Authors: Frölich Michael A. , Esame Alice , Zhang Kui , Wu Jihua , Owen John
Published: July 2012

Background

In recent years, several reports have indicated that maternal temperature elevations during labor may also be observed in the absence of an infection. Presumed noninfectious causes of maternal temperature elevations include epidural analgesia, endogenous heat production generated by the contracting uterus, and delivery in an overheated room. To investigate the potential causes of noninfectious maternal temperature changes during labor, we conducted a prospective cohort study in women scheduled for labor induction.

Methods

We recorded hourly oral temperatures from admission to delivery. We calculated whether temperature changed during labor in 81 women. We then determined if body mass index, and duration of labor, or time from rupture of amniotic sac to delivery, or oxytocin dose, would affect maternal temperature. To evaluate the possible role of epidural analgesia, we compared the temperature slope before and after starting epidural analgesia.

Results

We observed an overall significant linear trend of temperature over time with an estimated temperature slope of +0.017°C/h (P = 0.0093). Patients with a positive temperature trend had also a significantly longer time from rupture of membranes to delivery (P = 0.0077) and a higher body mass index (P = 0.0067). Epidural analgesia had no effect on the temperature trend.

Conclusions

In our cohort of patients, there was an overall significant linear trend of temperature over time after correcting for heterogeneity among patients. Temperature increase was associated with higher body mass index values and longer time from rupture of membranes to delivery. Epidural analgesia had no effect on maternal temperature.
Cervical Disk Replacement Combined With Cage Fusion for the Treatment of Multilevel Cervical Disk Herniation
Authors: Ren Xianjun , Chu Tongwei , Jiang Tao , Wang Weidong , Wang Jian , Li Changqing , Zhang Zhengfeng
Published: July 2012

Study Design:

This is a prospective study of artificial disk replacement combined with cage fusion for the treatment of multilevel cervical disk herniation.

Objective:

To evaluate the clinical outcome of Bryan cervical disk replacement combined with adjacent segment cage fusion in the treatment of patients with multilevel cervical disk herniation. To observe neurological improvement and interpret the radiographic findings.

Summary of Background Data:

It is generally considered that 1-level cervical disk replacement had an excellent intermediate clinical outcome. There was no final conclusion about the disk replacement for the treatment of multilevel cervical disk disease. The negative factors include possible complication, high cost, and contraindication for disk replacement at one of the multisegments. Disk replacement combined with adjacent segment cage fusion may be an option for the treatment of multilevel cervical disk disease for certain patients.

Methods:

There were 26 patients with multilevel cervical disk herniation who underwent 1-level disk replacement and adjacent segment cage fusion. Of the patients, there were 17 male and 9 female, aged between 35 and 63 (mean age 47 y). The herniated disk was located at C3–C4, C4–C5 in 1 case, C4–C5, C5–C6 in 11cases, C5–C6, C6–C7 in 7 cases, C4–C5, C6–C7 in 3 cases, and C4–C5, C5–C6, C6–C7 in 4 cases. There were 12 cases with myelopathy and 14 patients with radiculopathy. The stabilization and the range of motion of implanted disk, the fusion of cage, and the displacement of cage were observed on dynamic radiograph postoperatively. The clinical symptoms and the neurological functions were evaluated based on the Japanese Orthopaedic Association Scale score (17 points), neck disability index score, and Odom’s Criteria.

Results:

All patients underwent 1-level Bryan disk replacement and cage fusion on adjacent segment. The replacement segment and fusion segment were located next to each other among 23 patients. They were not next to each other in 3 cases. The follow-up was 24 to 47 months. Definite stabilization was achieved for all Bryan disks. The average range of motion at replaced level was 9.5 degrees postoperatively. Solid fusion was achieved in all cages. There was no subsidence or displacement of cage. The Japanese Orthopaedic Association Scale score (17 points) rose from 9.2 to 13.5 at final follow-up. The neck disability index was reduced from 40.8 to 28.5 at final follow-up. The clinical success (excellent/good/fair) based on Odom’s Criteria were 84.6%.

Conclusions:

Definite stabilization and satisfactory mobility were achieved after cervical disk replacement and cage fusion. This provides an effective option for the treatment of multilevel cervical disk herniation. The evaluation of high fusion rate of cage may need to accumulate more clinical cases.
Food transfers in capuchin monkeys: an experiment on partner choice
Authors: Sabbatini Gloria , De Bortoli Vizioli Aurora , Visalberghi Elisabetta , Schino Gabriele
Published: July 2012

Although most primates live in groups, experiments on reciprocity usually test individuals in dyads. This could hide the processes emerging in richer social settings, reducing the ecological validity of the results. We run an experiment on reciprocal food transfers testing capuchin monkeys (
Cebus apella
) in triads, so that subjects could choose to allow access to their food to either of their two partners. We tested the hypothesis that partner choice was related to a comparison of long-term social bonds with the two partners, more than to a comparison of recent food transfer events from the two partners. The results confirmed this hypothesis, thus supporting the notion that reciprocal partner preferences are based on long-term accounts of benefits that have been exchanged.
Collective cell migration: leadership, invasion and segregation
Authors: Kabla Alexandre J.
Published: July 2012

A number of biological processes, such as embryo development, cancer metastasis or wound healing, rely on cells moving in concert. The mechanisms leading to the emergence of coordinated motion remain however largely unexplored. Although biomolecular signalling is known to be involved in most occurrences of collective migration, the role of physical and mechanical interactions has only been recently investigated. In this study, a versatile framework for cell motility is implementedin silicoin order to study the minimal requirements for the coordination of a group of epithelial cells. We find that cell motility and cell–cell mechanical interactions are sufficient to generate a broad array of behaviours commonly observedin vitroandin vivo. Cell streaming, sheet migration and susceptibility to leader cells are examples of behaviours spontaneously emerging from these simple assumptions, which might explain why collective effects are so ubiquitous in nature. The size of the population and its confinement appear, in particular, to play an important role in the coordination process. In all cases, the complex response of the population can be predicted from the knowledge of the correlation length of the velocity field measured in the bulk of the epithelial layer. This analysis provides also new insights into cancer metastasis and cell sorting, suggesting, in particular, that collective invasion might result from an emerging coordination in a system where single cells are mechanically unable to invade.
Probabilistic patterns of interaction: the effects of link-strength variability on food web structure
Authors: Yeakel Justin D. , Guimarães Paulo R. , Novak Mark , Fox-Dobbs Kena , Koch Paul L.
Published: July 2012

Patterns of species interactions affect the dynamics of food webs. An important component of species interactions that is rarely considered with respect to food webs is the strengths of interactions, which may affect both structure and dynamics. In natural systems, these strengths are variable, and can be quantified as probability distributions. We examined how variation in strengths of interactions can be described hierarchically, and how this variation impacts the structure of species interactions in predator–prey networks, both of which are important components of ecological food webs. The stable isotope ratios of predator and prey species may be particularly useful for quantifying this variability, and we show how these data can be used to build probabilistic predator–prey networks. Moreover, the distribution of variation in strengths among interactions can be estimated from a limited number of observations. This distribution informs network structure, especially the key role of dietary specialization, which may be useful for predicting structural properties in systems that are difficult to observe. Finally, using three mammalian predator–prey networks (two African and one Canadian) quantified from stable isotope data, we show that exclusion of link-strength variability results in biased estimates of nestedness and modularity within food webs, whereas the inclusion of body size constraints only marginally increases the predictive accuracy of the isotope-based network. We find that modularity is the consequence of strong link-strengths in both African systems, while nestedness is not significantly present in any of the three predator–prey networks.
Evolution of the most common English words and phrases over the centuries
Authors: Perc Matjaž
Published: July 2012

By determining the most common English words and phrases since the beginning of the sixteenth century, we obtain a unique large-scale view of the evolution of written text. We find that the most common words and phrases in any given year had a much shorter popularity lifespan in the sixteenth century than they had in the twentieth century. By measuring how their usage propagated across the years, we show that for the past two centuries, the process has been governed by linear preferential attachment. Along with the steady growth of the English lexicon, this provides an empirical explanation for the ubiquity of Zipf's law in language statistics and confirms that writing, although undoubtedly an expression of art and skill, is not immune to the same influences of self-organization that are known to regulate processes as diverse as the making of new friends and World Wide Web growth.
Modelling the mechanical response ofurushilacquer subject to a change in relative humidity
Authors: Liu X. , Wildman R. D. , Ashcroft I. A. , Elmahdy A. E. , Ruiz P. D.
Published: July 2012

A hygromechanical model has been developed to simulate the in-service behaviour of the natural lacquerurushi, using a phenomenological description of viscoelasticity. The material and mechanical properties were determined as a function of the relative humidity (RH), and the relationship between RH and moisture content was determined. These properties served as inputs to a finite-element-based model that was then tested against experimental measurements of the depth-averaged stresses in a thin layer ofurushideposited on a substrate and exposed to changes in the environmental conditions. Good agreement was seen between the predicted and measured behaviour. The validated model was used to investigate the spatial and temperature variation of stress inurushifilms subjected to cyclic environmental conditioning.
Self-equilibrium and super-stability of truncated regular polyhedral tensegrity structures: a unified analytical solution
Authors: Zhang Li-Yuan , Li Yue , Cao Yan-Ping , Feng Xi-Qiao , Gao Huajian
Published: July 2012

In spite of their great importance and numerous applications in many civil, aerospace and biological systems, our understanding of tensegrity structures is still quite preliminary, fragmented and incomplete. Here we establish a unified closed-form analytical solution for the necessary and sufficient condition that ensures the existence of self-equilibrated and super-stable states for truncated regular polyhedral tensegrity structures, including truncated tetrahedral, cubic, octahedral, dodecahedral and icosahedral tensegrities.
How does adaptation sweep through the genome? Insights from long-term selection experiments
Authors: Burke Molly K.
Published: July 2012

A major goal in evolutionary biology is to understand the origins and fates of adaptive mutations. Natural selection may act to increase the frequency of de novo beneficial mutations, or those already present in the population as standing genetic variation. These beneficial mutations may ultimately reach fixation in a population, or they may stop increasing in frequency once a particular phenotypic state has been achieved. It is not yet well understood how different features of population biology, and/or different environmental circumstances affect these adaptive processes. Experimental evolution is a promising technique for studying the dynamics of beneficial alleles, as populations evolving in the laboratory experience natural selection in a replicated, controlled manner. Whole-genome sequencing, regularly obtained over the course of sustained laboratory selection, could potentially reveal insights into the mutational dynamics that most likely occur in natural populations under similar circumstances. To date, only a few evolution experiments for which whole-genome data are available exist. This review describes results from these resequenced laboratory-selected populations, in systems with and without sexual recombination. In asexual systems, adaptation from new mutations can be studied, and results to date suggest that the complete, unimpeded fixation of these mutations is not always observed. In sexual systems, adaptation from standing genetic variation can be studied, and in the admittedly few examples we have, the complete fixation of standing variants is not always observed. To date, the relative frequency of adaptation from new mutations versus standing variation has not been tested using a single experimental system, but recent studies usingCaenorhabditis elegansandSaccharomyces cerevisiaesuggest that this a realistic future goal.
Characterizing Regulatory and Functional Differentiation between Maize Mesophyll and Bundle Sheath Cells by Transcriptomic Analysis
Authors: Chang Yao-Ming , Liu Wen-Yu , Shih Arthur Chun-Chieh , Shen Meng-Ni , Lu Chen-Hua , Lu Mei-Yeh Jade , Yang Hui-Wen , Wang Tzi-Yuan , Chen Sean C.-C. , Chen Stella Maris , Li Wen-Hsiung , Ku Maurice S.B.
Published: July 2012

To study the regulatory and functional differentiation between the mesophyll (M) and bundle sheath (BS) cells of maize (Zea mays), we isolated large quantities of highly homogeneous M and BS cells from newly matured second leaves for transcriptome profiling by RNA sequencing. A total of 52,421 annotated genes with at least one read were found in the two transcriptomes. Defining a gene with more than one read per kilobase per million mapped reads as expressed, we identified 18,482 expressed genes; 14,972 were expressed in M cells, including 53 M-enriched transcription factor (TF) genes, whereas 17,269 were expressed in BS cells, including 214 BS-enriched TF genes. Interestingly, many TF gene families show a conspicuous BS preference in expression. Pathway analyses reveal differentiation between the two cell types in various functional categories, with the M cells playing more important roles in light reaction, protein synthesis and folding, tetrapyrrole synthesis, and RNA binding, while the BS cells specialize in transport, signaling, protein degradation and posttranslational modification, major carbon, hydrogen, and oxygen metabolism, cell division and organization, and development. Genes coding for several transporters involved in the shuttle of C4 metabolites and BS cell wall development have been identified, to our knowledge, for the first time. This comprehensive data set will be useful for studying M/BS differentiation in regulation and function.
Degradation of aromatic compounds through the β‐ketoadipate pathway is required for pathogenicity of the tomato wilt pathogen Fusarium oxysporum f. sp. lycopersici
Authors: Michielse Caroline B. , Reijnen Linda , Olivain Chantal , Alabouvette Claude , Rep Martijn
Published: July 2012

Plant roots react to pathogen attack by the activation of general and systemic resistance, including the lignification of cell walls and increased release of phenolic compounds in root exudate. Some fungi have the capacity to degrade lignin using ligninolytic extracellular peroxidases and laccases. Aromatic lignin breakdown products are further catabolized via the β‐ketoadipate pathway. In this study, we investigated the role of 3‐carboxy‐cis,cis‐muconate lactonizing enzyme (CMLE), an enzyme of the β‐ketoadipate pathway, in the pathogenicity of Fusarium oxysporum f. sp. lycopersici towards its host, tomato. As expected, the cmle deletion mutant cannot catabolize phenolic compounds known to be degraded via the β‐ketoadipate pathway. In addition, the mutant is impaired in root invasion and is nonpathogenic, even though it shows normal superficial root colonization. We hypothesize that the β‐ketoadipate pathway in plant‐pathogenic, soil‐borne fungi is necessary to degrade phenolic compounds in root exudate and/or inside roots in order to establish disease.
Complex karyotype predicts for inferior outcomes following reduced‐intensity conditioning allogeneic transplant for chronic lymphocytic leukaemia
Authors: Jaglowski Samantha M. , Ruppert Amy S. , Heerema Nyla A. , Bingman Anissa , Flynn Joseph M. , Grever Michael R. , Jones Jeffrey A. , Elder Patrick , Devine Steven M. , Byrd John C. , Andritsos Leslie A.
Published: July 2012

Complex karyotype (CK) on metaphase cytogenetics discriminates poor outcome in chronic lymphocytic leukaemia (CLL) patients undergoing salvage treatment; we hypothesized that it might provide prognostic information for patients undergoing allogeneic stem cell transplant. Fifty‐one CLL patients were analysed following transplant; 18‐month overall survival (OS), event‐free survival (EFS) and cumulative incidence of progression estimates were 35%, 14% and 63%, respectively, in patients with CK (n = 19) versus 83%, 68% and 29% in patients without (n = 32) (P ≤ 0·0001, P ≤ 0·0001, and P = 0·02). In patients with high‐risk interphase cytogenetics, CK remained predictive of worse OS (P = 0·02) and EFS (P = 0·009). These findings support further evaluation of metaphase karyotype in transplant risk assessment.
Indirect interactions in seagrasses: fish herbivores increase predation risk to sea urchins by modifying plant traits
Authors: Pagès Jordi F. , Farina Simone , Gera Alessandro , Arthur Rohan , Romero Javier , Alcoverro Teresa
Published: July 2012

The dominant paradigm of top‐down control of ecological communities through direct consumption pathways is giving way to a more nuanced understanding of trophic interactions with the recognition that subtler indirect effects can often play an important role in structuring communities. Direct and indirect trophic and non‐trophic processes could well be acting simultaneously within the same food web, and their overall effects may even interact with each other.

We studied indirect interactions in a relatively simple trophic system comprising a single producer, two herbivores and a guild of predators. In particular, we assessed whether (i) the principal herbivore fish, Sarpa salpa, is capable of modifying a seagrass trait, canopy height, by grazing and (ii) whether grazing‐induced habitat alteration can trigger an environment‐mediated modification of the interaction between herbivorous sea urchins Paracentrotus lividus and their predators.

We tested these hypotheses with field experiments including fish herbivore‐exclusion experiments (to examine the ability of S. salpa to modify seagrass habitats) and predation experiments using tethered sea urchins in a meadow with varying canopy heights (to test whether habitat modification can mediate urchin predation risk).

The effect of S. salpa herbivory was highly significant. Canopy height in herbivore‐excluded plots was more than 3·5 times higher than in uncaged control plots. In addition, adult sea urchin predation risk in the most highly grazed plots was 4–5 times higher than plots with higher canopy heights. In contrast, predation risk on juvenile urchins was not influenced by canopy height.

Our results show that predation pressure on a key herbivore can be modified both by the environmental context within which it finds itself and by the actions of another herbivore that modifies the plant traits that create this environmental context. These act as two discrete pathways that interact in potentially nonlinear ways, mediating top‐down control in these ecosystems. Herbivores, particularly when acting as ecosystem engineers, may have the potential to mediate and increase predation risk, as they substantially modify habitat structure, with consequences for refuge availability, among others. Assessing these indirect interactions is not just important to understand the functioning of the system itself but may have important management and conservation consequences.
Cardenolides in nectar may be more than a consequence of allocation to other plant parts: a phylogenetic study ofAsclepias
Authors: Manson Jessamyn S. , Rasmann Sergio , Halitschke Rayko , Thomson James D. , Agrawal Anurag A.
Published: July 2012

The primary function of secondary plant metabolites is thought to be defence against herbivores. The frequent occurrence of these same noxious compounds in floral nectar, which functions primarily to attract pollinators, has been seen as paradoxical.

Although these compounds may have an adaptive purpose in nectar, they may also occur as a nonadaptive consequence of chemical defence in other plant parts. If nectar chemistry reflects physiological constraints or passive leakage from other tissues, we expect that the identity and relative concentration of nectar cardenolides to be correlated with those of other plant parts; in contrast, discordant distributions of compounds in nectar and other tissues may suggest adaptive roles in nectar.

We compared the concentrations and identities of cardenolides in the nectar, leaves and flowers of 12 species from a monophyletic clade ofAsclepias. To measure putative toxicity of nectar cardenolides, we then examined the effects of a standard cardenolide (digoxin) on the behaviour of bumblebees, a common generalist pollinator ofAsclepias.

We found that the average cardenolide concentrations in nectar, leaves and flowers of the 12Asclepiasspecies were positively correlated as predicted by nonadaptive hypotheses. However, significant differences in the identities and concentrations of individual cardenolides between nectar and leaves suggest that the production or allocation of cardenolides may be independently regulated at each plant part. In addition, cardenolide concentrations in leaves and nectar exhibited no phylogenetic signal.

Surprisingly, bumblebees did not demonstrate an aversion to digoxin‐rich nectar, which may indicate that nectar cardenolides have little effect on pollination.

Although the idea that discordant patterns of secondary metabolites across tissue types may signal adaptive functions is attractive, there is evidence to suggest constraint contributes to nectar secondary chemistry. Further work testing the ecological impacts of such patterns will be critical in determining the functional significance of nectar cardenolides.
On cladistics and human–ape relationships
Authors: Lehtonen Samuli , Tuomisto Hanna , Sääksjärvi Ilari E. , Ruokolainen Kalle
Published: July 2012

The rebuttal of our correspondence (Lehtonen et al., Journal of Biogeography, 2011, 38, 805–808) by J. R. Grehan and J. H. Schwartz (Journal of Biogeography, 2011, 38, 2397–2404) reveals logical inconsistencies in their methodology. Here, we provide a clarification of these issues.
A randomised trial of nursing interventions supporting recovery of the postmastectomy patient
Authors: Cho Ho Soon Michelle , Davis Gail C , Paek Jae Eun , Rao Roshni , Zhao Hong , Xie Xian‐Jin , Yousef Mary G , Fedric Tara , Euhus David H , Leitch Marilyn
Published: July 2012

Aims and objectives.  This ABC to recovery study evaluated the combined and separate components of preoperative education and the effectiveness of wearing the Papilla Gown.

Background.  Surgical removal of the breast may lead to activity limitation, self‐image issues, discomfort and later complication of lymphoedema.

Design.  This study used experimental and longitudinal design.

Methods.  One hundred and forty‐five women undergoing mastectomies for stages two and three breast cancer were randomised into four groups: education and Papilla Gown, education only, gown only and control. The outcomes of activity (A), body image (B), comfort (C), knowledge and lymphoedema were assessed at baseline and/or 1 week and 6 months using three measures. All 145 participants completed the study questionnaires at first two measures, and forty‐six of these participants completed the questionnaires at 6 months postoperatively. The setting for the study included two clinics and hospitals. To examine statistical significance at each time point after surgery, 2‐way anovas were performed on ABC, knowledge and tape measurement to see whether there were any statistically significant differences between the four groups. All reported p‐values are two sided. All statistical analyses were performed using sas 9.2 for Windows.

Results.  The mean age of the sample was 55 years. The study revealed that women who received the combined intervention demonstrated greater activity. Women who wore the gown only had a greater comfort level and decreased lymphoedema. Women that received preoperative education experienced increased knowledge.

Conclusions.  Outcomes suggest that the combined intervention (ABCs to recovery) can improve recovery following mastectomy.

Relevance to clinical practice.  The results will be used to further modify the intervention and to increase awareness of nurse practitioners and other healthcare professionals of the specific needs of postmastectomy patients.
Evaluation of the effectiveness of hospital discharge planning and follow‐up in the primary care of patients with chronic obstructive pulmonary disease
Authors: Abad‐Corpa Eva , Royo‐Morales Tania , Iniesta‐Sánchez Javier , Carrillo‐Alcaraz Andrés , Rodríguez‐Mondejar Juan José , Saez‐Soto Ángeles Rosario , Vivo‐Molina Mª Carmen
Published: July 2012

Aims and objectives:  To evaluate the effectiveness of protocolised intervention for hospital discharge and follow‐up in the primary care of patients with chronic obstructive pulmonary disease (COPD).

Background:  Chronic obstructive pulmonary disease is one of the main causes of morbidity and mortality internationally.

Design:  A quasi‐experimental design was adopted, with a control group and it was pseudorandomised by services.

Methods:  Patients with COPD admitted to two tertiary‐level public hospitals in Spain were recruited (2007–2008). The outcome variables included: readmission rate, patient satisfaction (LOPSS12), quality of life (St. George′s Respiratory Questionnaire) and level of knowledge about COPD. 48 hours after admission, both groups were evaluated by specialist coordinating nurses. At the hospital, a coordinating nurse visited each patient in the experimental group every 24 hours to identify the main caregiver, provide information about the disease, explain treatment, identify care problems and needs and facilitate communication between professionals. 24 hours after discharge, the coordinating nurses informed the primary care nurses about patient discharge. The two nurses made the first home visit together. There were follow‐up phone calls at 2, 6, 12 and 24 weeks after discharge. A total of 143 patients were recruited (Intervention group=56; Control group=87).

Results:  The results showed a significant improvement in the evolution of quality of life, at 12 and 24 weeks after discharge; the level of knowledge about COPD revealed significant differences between the groups. There were no differences according to satisfaction or readmission rate. Multivariate analysis (non‐conditional logistic regression) showed the intervention to be ineffective in reducing the readmission rate.

Conclusions:  The planning of discharge for patients with COPD is effective in terms of improving the patients’ quality of life and level of knowledge about the disease.

Relevance to clinical practice:  The characteristics of patients with COPD make it necessary to include them in hospital discharge planning programmes.
Burst Firing in Gonadotrophin‐Releasing Hormone Neurones does not Require Ionotrophic GABA or Glutamate Receptor Activation
Authors: Lee K. , Liu X. , Herbison A. E.
Published: July 2012

Burst firing is a feature of many neuroendocrine cell types, including the hypothalamic gonadotrophin‐releasing hormone (GnRH) neurones that control fertility. The role of intrinsic and extrinsic influences in generating GnRH neurone burst firing is presently unclear. In the present study, we investigated the role of fast amino acid transmission in burst firing by examining the effects of receptor antagonists on bursting displayed by green fluorescent protein GnRH neurones in sagittal brain slices prepared from adult male mice. Blockade of AMPA and NMDA glutamate receptors with a cocktail of CNQX and AP5 was found to have no effects on burst firing in GnRH neurones. The frequency of bursts, dynamics of individual bursts, or percentage of firing clustered in bursts was not altered. Similarly, GABAA receptor antagonists bicuculline and picrotoxin had no effects upon burst firing in GnRH neurones. To examine the importance of both glutamate and GABA ionotrophic signalling, a cocktail including picrotoxin, CNQX and AP5 was used but, again, this was found to have no effects on GnRH neurone burst firing. To further question the impact of endogenous amino acid release on burst firing, electrical activation of anteroventral periventricular nuclei GABA/glutamate inputs to GnRH neurones was undertaken and found to have no impact on burst firing. Taken together, these observations indicate that bursting in GnRH neurones is not dependent upon acute ionotrophic GABA and glutamate signalling and suggest that extrinsic inputs to GnRH neurones acting through AMPA, NMDA and GABAA receptors are unlikely to be required for burst initiation in these cells.