bluuebunny/crossref_metadata_2025 huggingface dataset:
Addressing the “Wicked Problem” of Input Subsidy Programs in Africa
Authors: Ricker‐Gilbert Jacob , Jayne Thomas , Shively Gerald
Published: February 2013

This article reviews and critically assesses evidence on input subsidy programs implemented in selected countries over the past decade in Africa. We believe that input subsidies should be considered wicked problems because of the indeterminacy and difficulty surrounding how they are evaluated. Main findings from the current body of literature are that input subsidies provide some measurable but relatively small positive benefit to recipient households' well‐being. In addition, most studies find that subsidized inputs crowd out commercial input purchases, mitigating the extent to which subsidy programs contribute to total fertilizer use and crop production. African governments may wish to carefully consider the benefits and distributional effects of input subsidy programs relative to other uses of scarce public resources.
Hybrid regulatory models: a statistically tractable approach to model regulatory network dynamics
Authors: Ocone Andrea , Millar Andrew J. , Sanguinetti Guido
Published: February 2013

Motivation: Computational modelling of the dynamics of gene regulatory networks is a central task of systems biology. For networks of small/medium scale, the dominant paradigm is represented by systems of coupled non-linear ordinary differential equations (ODEs). ODEs afford great mechanistic detail and flexibility, but calibrating these models to data is often an extremely difficult statistical problem.

Results: Here, we develop a general statistical inference framework for stochastic transcription–translation networks. We use a coarse-grained approach, which represents the system as a network of stochastic (binary) promoter and (continuous) protein variables. We derive an exact inference algorithm and an efficient variational approximation that allows scalable inference and learning of the model parameters. We demonstrate the power of the approach on two biological case studies, showing that the method allows a high degree of flexibility and is capable of testable novel biological predictions.

Availability and implementation:  http://homepages.inf.ed.ac.uk/gsanguin/software.html.

Supplementary information:  Supplementary data are available at Bioinformatics online.

Contact:  G.Sanguinetti@ed.ac.uk
Prevalence of Child Sexual Abuse in Pediatric Patients With Chronic Abdominal Pain
Authors: Sonneveld Liza P. , Brilleslijper‐Kater Sonja N. , Benninga Marc A. , van Konijnenburg Eva M.M. Hoytema , Sieswerda‐Hoogendoorn Tessa , Teeuw Arianne H.
Published: February 2013

Background and Objectives:

A history of sexual abuse is to be found in approximately 40% of all adult patients with gastrointestinal complaints. Data on the prevalence of child sexual abuse (CSA) in children with chronic abdominal pain (CAP) are lacking. The objective of this systematic review is to determine the prevalence of CSA in pediatric patients with CAP.

Methods:

We conducted a systematic literature search in the electronic databases MEDLINE, EMBASE, PsychInfo, and ERIC. Reference lists of relevant articles were scanned for additional citations. We selected case‐control, cohort and cross‐sectional studies investigating the prevalence of CSA in children with CAP, ages 0 to 18 years. Data were extracted from relevant studies, which were assessed for methodological quality by 2 independent reviewers. Prevalence of CSA was the main outcome measure.

Results:

The literature search yielded a total of 269 articles. Only 2 studies met our inclusion criteria, reporting CSA in 2.1% and 8.0% of children (age range 4–21 years) with CAP. Both studies were conducted in small groups (n = 48 and n = 50) without control group(s) and did not use standardized or validated instruments for diagnosing CSA.

Conclusions:

According to existing data, the prevalence of a history of CSA in pediatric patients with CAP is lower than in adult patients; however, no well‐designed studies have been conducted in children. Future research is required to determine a reliable prevalence of CSA in children with CAP.
The affinity purification and characterization of ATP synthase complexes from mitochondria
Authors: Runswick Michael J. , Bason John V. , Montgomery Martin G. , Robinson Graham C. , Fearnley Ian M. , Walker John E.
Published: February 2013

The mitochondrial F
1
-ATPase inhibitor protein, IF
1
, inhibits the hydrolytic, but not the synthetic activity of the F-ATP synthase, and requires the hydrolysis of ATP to form the inhibited complex. In this complex, the α-helical inhibitory region of the bound IF
1
occupies a deep cleft in one of the three catalytic interfaces of the enzyme. Its N-terminal region penetrates into the central aqueous cavity of the enzyme and interacts with the γ-subunit in the enzyme's rotor. The intricacy of forming this complex and the binding mode of the inhibitor endow IF
1
with high specificity. This property has been exploited in the development of a highly selective affinity procedure for purifying the intact F-ATP synthase complex from mitochondria in a single chromatographic step by using inhibitor proteins with a C-terminal affinity tag. The inhibited complex was recovered with residues 1–60 of bovine IF
1
with a C-terminal green fluorescent protein followed by a His-tag, and the active enzyme with the same inhibitor with a C-terminal glutathione-
S
-transferase domain. The wide applicability of the procedure has been demonstrated by purifying the enzyme complex from bovine, ovine, porcine and yeast mitochondria. The subunit compositions of these complexes have been characterized. The catalytic properties of the bovine enzyme have been studied in detail. Its hydrolytic activity is sensitive to inhibition by oligomycin, and the enzyme is capable of synthesizing ATP in vesicles in which the proton-motive force is generated from light by bacteriorhodopsin. The coupled enzyme has been compared by limited trypsinolysis with uncoupled enzyme prepared by affinity chromatography. In the uncoupled enzyme, subunits of the enzyme's stator are degraded more rapidly than in the coupled enzyme, indicating that uncoupling involves significant structural changes in the stator region.
The structure of F
1
-ATPase from
Saccharomyces cerevisiae
inhibited by its regulatory protein IF
1
Authors: Robinson Graham C. , Bason John V. , Montgomery Martin G. , Fearnley Ian M. , Mueller David M. , Leslie Andrew G. W. , Walker John E.
Published: February 2013

The structure of F
1
-ATPase from
Saccharomyces cerevisiae
inhibited by the yeast IF
1
has been determined at 2.5 Å resolution. The inhibitory region of IF
1
from residues 1 to 36 is entrapped between the C-terminal domains of the α
DP
- and β
DP
-subunits in one of the three catalytic interfaces of the enzyme. Although the structure of the inhibited complex is similar to that of the bovine-inhibited complex, there are significant differences between the structures of the inhibitors and their detailed interactions with F
1
-ATPase. However, the most significant difference is in the nucleotide occupancy of the catalytic β
E
-subunits. The nucleotide binding site in β
E
-subunit in the yeast complex contains an ADP molecule without an accompanying magnesium ion, whereas it is unoccupied in the bovine complex. Thus, the structure provides further evidence of sequential product release, with the phosphate and the magnesium ion released before the ADP molecule.
Indigenous
Vibrio cholerae
strains from a non-endemic region are pathogenic
Authors: Islam Atiqul , Labbate Maurizio , Djordjevic Steven P. , Alam Munirul , Darling Aaron , Melvold Jacqueline , Holmes Andrew J. , Johura Fatema T. , Cravioto Alejandro , Charles Ian G. , Stokes H. W.
Published: February 2013

Of the 200+ serogroups of
Vibrio cholerae
, only O1 or O139 strains are reported to cause cholera, and mostly in endemic regions. Cholera outbreaks elsewhere are considered to be via importation of pathogenic strains. Using established animal models, we show that diverse
V. cholerae
strains indigenous to a non-endemic environment (Sydney, Australia), including non-O1/O139 serogroup strains, are able to both colonize the intestine and result in fluid accumulation despite lacking virulence factors believed to be important. Most strains lacked the type three secretion system considered a mediator of diarrhoea in non-O1/O13
V. cholerae
. Multi-locus sequence typing (MLST) showed that the Sydney isolates did not form a single clade and were distinct from O1/O139 toxigenic strains. There was no correlation between genetic relatedness and the profile of virulence-associated factors. Current analyses of diseases mediated by
V. cholerae
focus on endemic regions, with only those strains that possess particular virulence factors considered pathogenic. Our data suggest that factors other than those previously well described are of potential importance in influencing disease outbreaks.
Diffusion of individual birds in starling flocks
Authors: Cavagna A. , Queirós S. M. Duarte , Giardina I. , Stefanini F. , Viale M.
Published: February 2013

Flocking is a paradigmatic example of collective animal behaviour, where global order emerges out of self-organization. Each individual has a tendency to align its flight direction with those of neighbours, and such a simple form of interaction produces a state of collective motion of the group. When compared with other cases of collective ordering, a crucial feature of animal groups is that the interaction network is not fixed in time, as each individual moves and continuously changes its neighbours. The possibility to exchange neighbours strongly enhances the stability of global ordering and the way information is propagated through the group. Here, we assess the relevance of this mechanism in large flocks of starlings (
Sturnus vulgaris
). We find that birds move faster than Brownian walkers both with respect to the centre of mass of the flock, and with respect to each other. Moreover, this behaviour is strongly anisotropic with respect to the direction of motion of the flock. We also measure the amount of neighbours reshuffling and find that neighbours change in time exclusively as a consequence of the random fluctuations in the individual motion, so that no specific mechanism to keep one's neighbours seems to be enforced. On the contrary, our findings suggest that a more complex dynamical process occurs at the border of the flock.
The metabolic and mechanical costs of step time asymmetry in walking
Authors: Ellis Richard G. , Howard Kevin C. , Kram Rodger
Published: February 2013

Animals use both pendular and elastic mechanisms to minimize energy expenditure during terrestrial locomotion. Elastic gaits can be either bilaterally symmetric (e.g. run and trot) or asymmetric (e.g. skip, canter and gallop), yet only symmetric pendular gaits (e.g. walk) are observed in nature. Does minimizing metabolic and mechanical power constrain pendular gaits to temporal symmetry? We measured rates of metabolic energy expenditure and calculated mechanical power production while healthy humans walked symmetrically and asymmetrically at a range of step and stride times. We found that walking with a 42 per cent step time asymmetry required 80 per cent (2.5 W kg−1) more metabolic power than preferred symmetric gait. Positive mechanical power production increased by 64 per cent (approx. 0.24 W kg−1), paralleling the increases we observed in metabolic power. We found that when walking asymmetrically, subjects absorbed more power during double support than during symmetric walking and compensated by increasing power production during single support. Overall, we identify inherent metabolic and mechanical costs to gait asymmetry and find that symmetry is optimal in healthy human walking.
Evaluating factors that predict the structure of a commensalistic epiphyte–phorophyte network
Authors: Sáyago Roberto , Lopezaraiza-Mikel Martha , Quesada Mauricio , Álvarez-Añorve Mariana Yolotl , Cascante-Marín Alfredo , Bastida Jesus Ma.
Published: February 2013

A central issue in ecology is the understanding of the establishment of biotic interactions. We studied the factors that affect the assembly of the commensalistic interactions between vascular epiphytes and their host plants. We used an analytical approach that considers all individuals and species of epiphytic bromeliads and woody hosts and non-hosts at study plots. We built models of interaction probabilities among species to assess if host traits and abundance and spatial overlap of species predict the quantitative epiphyte–host network. Species abundance, species spatial overlap and host size largely predicted pairwise interactions and several network metrics. Wood density and bark texture of hosts also contributed to explain network structure. Epiphytes were more common on large hosts, on abundant woody species, with denser wood and/or rougher bark. The network had a low level of specialization, although several interactions were more frequent than expected by the models. We did not detect a phylogenetic signal on the network structure. The effect of host size on the establishment of epiphytes indicates that mature forests are necessary to preserve diverse bromeliad communities.
Transgenerational acclimatization in an herbivore–host plant relationship
Authors: Cahenzli Fabian , Erhardt Andreas
Published: February 2013

Twenty years ago, scientists began to recognize that parental effects are one of the most important influences on progeny phenotype. Consequently, it was postulated that herbivorous insects could produce progeny that are acclimatized to the host plant experienced by the parents to improve progeny fitness, because host plants vary greatly in quality and quantity, and can thus provide important cues about the resources encountered by the next generation. However, despite the possible profound implications for our understanding of host-use evolution of herbivores, host-race formation and sympatric speciation, intense research has been unable to verify transgenerational acclimatization in herbivore–host plant relationships. We rearedCoenonympha pamphiluslarvae in the parental generation (P) on high- and low-quality host plants, and reared the offspring (F1) of both treatments again on high- and low-quality plants. We tested not only for maternal effects, as most previous studies, but also for paternal effects. Our results show that parents experiencing predictive cues on their host plant can indeed adjust progeny's phenotype to anticipated host plant quality. Maternal effects affected female and male offspring, whereas paternal effects affected only male progeny. We here verify, for the first time to our knowledge, the long postulated transgenerational acclimatization in an herbivore–host plant interaction.
Outcomes of co-infection by two potyviruses: implications for the evolution of manipulative strategies
Authors: Salvaudon Lucie , De Moraes Consuelo M. , Mescher Mark C.
Published: February 2013

Recent studies have documented effects of plant viruses on host plants that appear to enhance transmission by insect vectors. But, almost no empirical work has explored the implications of such apparent manipulation for interactions among co-infecting pathogens. We examined single and mixed infections of two potyviruses, watermelon mosaic virus (WMV) and zucchini yellow mosaic virus (ZYMV), that frequently co-occur in cucurbitaceae populations and share the same aphid vectors. We found that ZYMV isolates replicated at similar rates in single and mixed infections, whereas WMV strains accumulated to significantly lower levels in the presence of ZYMV. Furthermore, ZYMV induced changes in leaf colour and volatile emissions that enhanced aphid (Aphis gossypii) recruitment to infected plants. By contrast, WMV did not elicit strong effects on plant–aphid interactions. Nevertheless, WMV was still readily transmitted from mixed infections, despite fairing poorly in in-plant competition. These findings suggest that pathogen effects on host–vector interactions may well influence competition among co-infecting pathogens. For example, if non-manipulative pathogens benefit from the increased vector traffic elicited by manipulative competitors, their costs of competition may be mitigated to some extent. Conversely, the benefits of manipulation may be limited by free-rider effects in systems where there is strong competition among pathogens for host resources and/or access to vectors.
Intracellular glucocorticoid receptors in spleen, but not skin, vary seasonally in wild house sparrows (Passer domesticus)
Authors: Lattin Christine R. , Waldron-Francis K. , Romero L. Michael
Published: February 2013

Over the short-term and at physiological doses, acute increases in corticosterone (CORT) titres can enhance immune function. There are predictable seasonal patterns in both circulating CORT and immune function across many animal species, but whether CORT receptor density in immune tissues varies seasonally is currently unknown. Using radioligand binding assays, we examined changes in concentrations of glucocorticoid receptors (GR) and mineralocorticoid receptors (MR) in spleen and skin in wild-caught house sparrows in Massachusetts during six different life-history stages: moult, early winter, late winter, pre-egg-laying, breeding and late breeding. Splenic GR and MR binding were highest during the pre-laying period. This may help animals respond to immune threats through increased lymphocyte proliferation and/or an increase in delayed-type hypersensitivity reactions, both of which CORT can stimulate and in which spleen is involved. A decrease in splenic GR and MR during the late breeding period coincides with low baseline and stress-induced CORT, suggesting immune function in spleen may be relatively CORT-independent during this period. We saw no seasonal patterns in GR or MR in skin, suggesting skin's response to CORT is modulated primarily via changes in circulating CORT titres and/or via local production of CORT in response to wounding and other noxious stimuli.
Kin recognition affects plant communication and defence
Authors: Karban Richard , Shiojiri Kaori , Ishizaki Satomi , Wetzel William C. , Evans Richard Y.
Published: February 2013

The ability of many animals to recognize kin has allowed them to evolve diverse cooperative behaviours; such ability is less well studied for plants. Many plants, including
Artemisia tridentata
, have been found to respond to volatile cues emitted by experimentally wounded neighbours to increase levels of resistance to herbivory. We report that this communication was more effective among
A. tridentata
plants that were more closely related based on microsatellite markers. Plants in the field that received cues from experimentally clipped close relatives experienced less leaf herbivory over the growing season than those that received cues from clipped neighbours that were more distantly related. These results indicate that plants can respond differently to cues from kin, making it less likely that emitters will aid strangers and making it more likely that receivers will respond to cues from relatives. More effective defence adds to a growing list of favourable consequences of kin recognition for plants.
Polygyny among the Tsimane of Bolivia: an improved method for testing the polygyny–fertility hypothesis
Authors: Winking Jeffrey , Stieglitz Jonathan , Kurten Jenna , Kaplan Hillard , Gurven Michael
Published: February 2013

The polygyny–fertility hypothesis states that polygyny is associated with reduced fertility for women and is supported by a large body of literature. This finding is important, because theoretical models of polygyny often differentiate systems based on the degree to which women are forced or willingly choose to enter polygynous marriages. The fact that polygyny tends to be associated with reduced fertility has been presented as evidence that polygyny is often less favourable for women, and that women must, therefore, be pressured into accepting such arrangements. Previous studies, however, have been hampered by the non-random assignment of women into monogamous and polygynous unions (i.e. self-selection), as differences between these groups of women might explain some of the effects. Furthermore, the vast majority of such studies focus on sub-Saharan populations. We address these problems in our analysis of women's fertility in polygynous marriages among the Tsimane of Bolivia. We offer a more robust method for assessing the impact of polygynous marriage on reproductive outcomes by testing for intra-individual fertility effects among first wives as they transition from monogamous to polygynous marriage. We report a significant link between polygyny and reduced fertility when including all cases of polygyny; however, this association disappears when testing only for intra-individual effects.
Cell-type-dependent activities of regulatory regions and E2 proteins derived from carcinogenic and non-carcinogenic human alphapapillomaviruses
Authors: Schenker Astrid , Straub Elke , Iftner Thomas , Stubenrauch Frank
Published: February 2013

A large number of studies have revealed that persistent infections with certain human papillomavirus (HPV) types are necessary for the development of invasive cancer of the cervix. Recent studies have shown that not only do the major carcinogenic HPV types 16 and 18 encode E6 and E7 oncoproteins with immortalizing activity but also the very weakly or non-carcinogenic types 53, 66, 70 and 82. Currently, it is unknown whether transcriptional differences exist between these viruses that account for carcinogenicityin vivo. Therefore, we compared for the first time the activities of the upstream regulatory regions (URRs) that driveE6andE7expression derived from HPV16, -18, -31, -53, -66, -70 and -82 in the absence and presence of the viral E2 transcriptional regulator. URR activities in the absence of E2 varied widely and were further modulated by the cellular background. The co-expression of homologous E2 proteins resulted in repression of the URRs of only some HPV types and this varied with cell type. Activation by E2 proteins was less cell-type dependent but differed in an HPV-type-dependent manner. However, basal URR activity, repression of the URR by E2 and transcriptional activation by E2 did not correlate with HPV carcinogenicityin vivo. In summary, our data do not support the model that the transcriptional activity of human alphapapillomavirus types correlates with epidemiological risk classification.
Preliminary epitope mapping of Torque teno sus virus 1 and 2 putative capsid protein and serological detection of infection in pigs
Authors: Jarosova Veronika , Celer Vladimír
Published: February 2013

The aim of this work is to identify antigenic regions within the ORF1 protein of Torque teno sus virus 1 (TTSuV1) and Torque teno virus sus 2 (TTSuV2) that could be used as antigens to detect virus-specific antibodies following infection in pigs. Protein sequences of TTSuV ORF1 genes were analysed to predict linear antigenic epitopes. Synthesized peptides were analysed for serological reactivity with swine sera. Such an antigenic region was identified at the C terminus of the ORF1 protein of both viruses and showed serological reactivity with 78 % (TTSuV1) and 88 % (TTSuV2) of swine sera. An ELISA with an immunodominant peptide as antigen was used to examine the sera of piglets, aged 4–20 weeks, and adults. Results indicated that TTSuV1- and TTSuV2-specific antibodies were detectable at 4 weeks. Antibody titres increased from week 10 and peaked at week 20. A relatively high antibody titre persisted to adulthood.
MicroRNAome of Spodoptera frugiperda cells (Sf9) and its alteration following baculovirus infection
Authors: Mehrabadi Mohammad , Hussain Mazhar , Asgari Sassan
Published: February 2013

MicroRNAs (miRNAs) as small non-coding RNAs play important roles in many biological processes such as development, cell signalling and immune response. Studies also suggest that miRNAs are important in host–virus interactions where the host limits virus infection by differentially expressing miRNAs that target essential viral genes. Here, we identified conserved and new miRNAs from Spodoptera frugiperda cells (Sf9) using a combination of deep sequencing and bioinformatics as well as experimental approaches. S. frugiperda miRNAs share common features of miRNAs in other organisms, such as uracil (U) at the 5′ end of miRNA. The 5′ ends of the miRNAs were more conserved than the 3′ ends, revealing evolutionary protection of the seed region in miRNAs. The predominant miRNAs were found to be conserved among arthropods. The majority of homologous miRNAs were found in Bombyx mori, with 76 of the 90 identified miRNAs. We found that seed shifting and arm switching have happened in this insect's miRNAs. Expression levels of the majority of miRNAs changed following baculovirus infection. Results revealed that baculovirus infection mainly led to an overall suppression of cellular miRNAs. We found four different genes being regulated by sfr-miR-184 at the post-transcriptional level. The data presented here further support conservation of miRNAs in insects and other organisms. In addition, the results reveal a differential expression of host miRNAs upon baculovirus infection, suggesting their potential roles in host–virus interactions. Seed shifting and arm switching happened during evolution of miRNAs in different insects and caused miRNA diversification, which led to changes in the target repository of miRNAs.
Reciprocal Control of Anaplerotic Phosphoenolpyruvate Carboxylase by in Vivo Monoubiquitination and Phosphorylation in Developing Proteoid Roots of Phosphate-Deficient Harsh Hakea
Authors: Shane Michael W. , Fedosejevs Eric T. , Plaxton William C.
Published: February 2013

Accumulating evidence indicates important functions for phosphoenolpyruvate (PEP) carboxylase (PEPC) in inorganic phosphate (Pi)-starved plants. This includes controlling the production of organic acid anions (malate, citrate) that are excreted in copious amounts by proteoid roots of nonmycorrhizal species such as harsh hakea (Hakea prostrata). This, in turn, enhances the bioavailability of mineral-bound Pi by solubilizing Al3+, Fe3+, and Ca2+ phosphates in the rhizosphere. Harsh hakea thrives in the nutrient-impoverished, ancient soils of southwestern Australia. Proteoid roots from Pi-starved harsh hakea were analyzed over 20 d of development to correlate changes in malate and citrate exudation with PEPC activity, posttranslational modifications (inhibitory monoubiquitination versus activatory phosphorylation), and kinetic/allosteric properties. Immature proteoid roots contained an equivalent ratio of monoubiquitinated 110-kD and phosphorylated 107-kD PEPC polypeptides (p110 and p107, respectively). PEPC purification, immunoblotting, and mass spectrometry indicated that p110 and p107 are subunits of a 430-kD heterotetramer and that they both originate from the same plant-type PEPC gene. Incubation with a deubiquitinating enzyme converted the p110:p107 PEPC heterotetramer of immature proteoid roots into a p107 homotetramer while significantly increasing the enzyme’s activity under suboptimal but physiologically relevant assay conditions. Proteoid root maturation was paralleled by PEPC activation (e.g. reduced Km [PEP] coupled with elevated I50 [malate and Asp] values) via in vivo deubiquitination of p110 to p107, and subsequent phosphorylation of the deubiquitinated subunits. This novel mechanism of posttranslational control is hypothesized to contribute to the massive synthesis and excretion of organic acid anions that dominates the carbon metabolism of the mature proteoid roots.
The variable projection method for waveform inversion with an unknown source function
Authors: Rickett James
Published: February 2013

This paper compares three alternative algorithms for simultaneously estimating a source wavelet at the same time as an earth model in full‐waveform inversion: (i) simultaneous descent, (ii) alternating descent and (iii) descent with the variable projection method. The latter is a technique for solving separable least‐squares problems that is well‐known in the applied mathematics literature. When applied to full‐waveform inversion, it involves making the source wavelet an implicit function of the earth model via a least‐squares filter‐estimation process. Since the source wavelet becomes purely a function of medium parameters, it no longer needs to be treated as a separate unknown in the inversion. Essentially, the predicted data are projected onto the measured data in a least‐squares sense at every function evaluation, making use of the fact that the filter estimation problem is trivial when compared to the full‐waveform inversion problem. Numerical tests on a simple 1D model indicate that the variable projection method gives the best result; actually producing results in quality that are very similar to control experiments with a known, correct wavelet.
Compressive strength and elastic properties of a transversely isotropic calcareous mudstone
Authors: Miller Douglas , Plumb Richard , Boitnott Gregory
Published: February 2013

This paper reports measurements of static and dynamic elastic properties plus compressive strength performed on a block of calcareous mudstone retrieved from an exploration well. Measurements of mechanical properties indicate that the mudstone is anisotropic with respect to all three properties. A detailed analysis of the elastic moduli computed using small unload reload cycles and simultaneous ultrasonic wave velocities shows both strong anisotropy and strong anelasticity. Surprisingly, the measurements are consistent with a mathematical description of a special type of anisotropic linear viscoelastic medium that is obtained by adding a set of compliant elements (e.g., contacts between clay particles, kerogen lenses, or micro‐fractures) to an isotropic viscoelastic solid. This medium is fully characterized by density plus four parameters defining the viscoelastic solid and the excess normal compliance associated with the compliant elements. The mathematical model predicts a full set of parameters characterizing a transversely isotropic medium with a vertical axis of symmetry (a ‘tiv’ medium) for both low‐ and high‐strain rate behaviour.
Exploring Peri‐urbanisation and Agricultural Systems in the Melbourne Region
Authors: BUTT ANDREW
Published: February 2013

Processes of peri‐urbanisation emerge from a range of drivers that differ according to socio‐economic and geographic settings. Using the Melbourne outer peri‐urban region, this paper explores these processes using a set of indicator variables for four identified modes of peri‐urbanisation: exurbanisation, hidden urbanisation, retiree mobility, and displaced suburbia. This paper considers the relationships between these modes and their locational distribution. It then considers the potential influence of these processes on the characteristics of farming systems in the subject region through regression models. Significant relationships are evident in several instances, specifically the differences that emerge between retiree mobility and exurbanisation or displaced suburbia (processes linked to urban proximity). These latter processes also appear to influence features of local agricultural systems, including farm scale and type.
The effectiveness of Bayesian state‐space models for estimating behavioural states from movement paths
Authors: Beyer Hawthorne L. , Morales Juan M. , Murray Dennis , Fortin Marie‐Josée
Published: February 2013

Bayesian state‐space movement models have been proposed as a method of inferring behavioural states from movement paths (Morales et al. 2004), thereby providing insight into the behavioural processes from which patterns of animal space use arise in heterogeneous environments. It is not clear, however, how effective state‐space models are at estimating behavioural states.

We use stochastic simulations of two movement models to quantify how behavioural state movement characteristics affect classification error. State‐space movement models can be a highly effective approach to estimating behavioural states from movement paths.

Classification accuracy was contingent upon the degree of separation between the distributions that characterize the states (e.g. step length and turn angle distributions) and the relative frequency of the behavioural states. In the best case scenarios classification accuracy approached 100%, but was close to 0% when step length and turn angle distributions of each state were similar, or when one state was rare. Mean classification accuracy was uncorrelated with path length, but the variance in classification accuracy was inversely related to path length.

Importantly, we find that classification accuracy can be predicted based on the separation between distributions that characterize the movement paths, thereby providing a method of estimating classification accuracy for real movement paths. We demonstrate this approach using radiotelemetry relocation data of 34 moose (Alces alces).

We conclude that Bayesian state‐space models offer powerful new opportunities for inferring behavioural states from relocation data.
Sources of Sensory Innervation of the Hip Joint Capsule in the Rabbit – A Retrograde Tracing Study
Authors: Dudek A. , Chrószcz A. , Janeczek M. , Sienkiewicz W. , Kaleczyc J.
Published: February 2013

The aim of the study was to investigate the sensory innervation of the hip joint capsule in the rabbit. Individual animals were injected with retrograde fluorescent tracer Fast Blue (FB) into the lateral aspect of the left hip joint capsule (group LAT, n = 5) or into the medial aspect of the hip joint capsule (group MED, n = 5), respectively. FB‐positive (FB+) neurons were found within ipsilateral lumbar (L) and sacral (S) dorsal root ganglia (DRG) from L7 to S2 (group LAT) and from L6 to S4 (group MED). They were round or oval in shape with a diameter of 20–90 μm. The neurons were evenly distributed throughout the ganglia. The average number of FB+ neurons was 16 ± 2.8 and 27.6 ± 3.5 in rabbits from LAT and MED, respectively. The largest average number of FB+ neurons in animals of group LAT was found within the S1 DRG (8 ± 1.7), while S2 ganglion contained the smallest number of the neurons (3.6 ± 1). In the L7 DRG, the average number of FB+ neurons was 6.2 ± 1.6. In rabbits of MED group, the largest number of FB+ neurons was found within the S1 DRG (13.4 ± 4), while the smallest one was found within the S3 ganglion (1.4 ± 0.4). In L6, L7, S2 and S4 ganglia, the number of retrogradely labelled neurons amounted to 1.6 ± 0.5, 4 ± 1.5, 4.4 ± 1.5 and 2.8 ± 1.7, respectively. The data obtained can be very useful for further investigations regarding the efficacy of denervation in the therapy of hip joint disorders in rabbits.
Comparison of the Morphometric Features of the Left and Right Horse Kidneys: A Stereological Approach
Authors: Bolat D. , Bahar S. , Tipirdamaz S. , Selcuk M. L.
Published: February 2013

The aims of this study were to determine the total volume of the horse kidney and volume fractions of its functional subcomponents (cortex, medulla, renal pelvis) using stereological methods and investigate any possible difference in the functional subcomponents of the right and left kidneys that may arise from differences in shape. The study was carried out on the kidneys of 5 horses of different breed and sex. The weight of the kidneys was measured by a digital scale, and kidney volume was calculated by Archimedes' principle. Total kidney volume and volume fractions of subcomponents of the right and left kidneys were estimated by the Cavalieri's principle. The weights of the right and left kidneys were 550 ± 25 g and 585 ± 23 g, respectively. The volumes of the right and left kidneys estimated using the Cavalieri method were 542 ± 46 ml and 581 ± 29 ml. The relative organ weight of the kidneys was calculated as 1:330. The densities of the right and left kidneys were determined to be 1.01 and 1.00, respectively. The mean volume fractions of the cortex, medulla and renal pelvis were determined as 55.6, 42.7 and 1.7 in both kidneys. No statistically significant difference existed between morphometric data pertaining to the right and left kidneys (P > 0.05). To determine precisely whether differences in shape cause any difference in the functional subcomponents of the right and left kidneys requires further investigation of differences in the number of microscopically functional unit of the kidney such as renal glomeruli and nephrons.
Evaluation of Efficacy and Safety of Recombinant Sperm‐Specific Contraceptive Vaccine in Albino Mice
Authors: Goyal Shipra , Manivannan Boomi , Kumraj Ganesh R. , Ansari Abdul S. , Lohiya Nirmal K.
Published: February 2013

Problem

This study was undertaken to evaluate the efficacy and safety of recombinant SP‐10 protein for male contraception.

Methods of study

Adult male mice were divided into five groups. Group I was placebo‐treated control while Groups II–V were immunized with recombinant SP‐10 protein on day 0 and 21 with different doses (range 25–100 μg). From each Group, animals were put for mating fertility test. Histological and hematological parameters, sperm characteristics, serum clinical biochemistry and testosterone levels were investigated.

Results

Group I showed normal fertility. Group II–V showed dose dependent reduction in fertility. In contrast, at higher dose (75 and 100 μg), all animals were sterile for three months. Further, all parameters under investigation in experimental groups were comparable to those of control animals.

Conclusion

Our study has put forth a proof of concept for male contraception for the first time, which may be considered suitable for contraceptive vaccine development.
Tolerance Induction at the Early Maternal–Placental Interface Through Selective Cell Recruitment and Targeting by Immune Polypeptides
Authors: Pérez Leirós Claudia , Ramhorst Rosanna
Published: February 2013

Pregnancy challenges immune cells and immunomodulatory circuits of the mother and the developing fetus to dynamically adapt to each other in an homeostatic and tolerant environment for fetal growth. This entails the coordination of multiple cellular processes all devoted to accommodate and nourish the fetus while protecting the mother from endogenous and exogenous threatens. From the earliest stages of pregnancy, several strategies to efficiently communicate immune and trophoblast cells within the interface or at a distance were identified and chemokines might act at on different targets through direct or indirect mechanisms. Here, we briefly review some mechanisms of T regulatory cell recruitment to the early maternal–placental interfaces to accomplish immunotolerance and homeostatic control and we discuss evidence on two locally released polypeptides, RANTES (regulated on activation, normal, T‐cell expressed, and secreted) and vasoactive intestinal peptide (VIP), as novel contributors to the multiplicity of immune tolerant responses and uterine quiescence requirements.
Retinal vascular caliber is associated with renal function in apparently healthy subjects
Authors: Daien Vincent , Kawasaki Ryo , Villain Max , Ribstein Jean , Du Cailar Guilhem , Mimran Albert , Fesler Pierre
Published: February 2013

Purpose:  To assess the relation between retinal vascular caliber and renal function.

Patients and methods:  Eighty apparently healthy subjects screened for cardiovascular risk factors (mean age 47 years, 51% female, 36% hypertensive, without diabetes or renal dysfunction) were recruited. Retinal vascular calibers were measured from fundus photographs and expressed as central retinal artery and venular equivalent. Renal function was assessed by measurement of glomerular filtration rate (urinary clearance of 99mTc‐DTPA) and urinary albumin/creatinine ratio.

Results:  Mean glomerular filtration rate was 117 ml/min/1.73m2. Overall, central retinal artery and venular equivalent were positively correlated with glomerular filtration rate (r = +0.31, p = 0.005 and r = +0.30, p = 0.006, respectively). In addition, central retinal artery equivalent was negatively correlated with urinary albumin/creatinine ratio (r = −0.34, p = 0.002). No significant relationship was found between central retinal venular equivalent and urinary albumin/creatinine ratio (r = +0.12, p = 0.32). The observed relations between retinal vascular calibers and renal function parameters remained significant after adjusting for potential confounding factors.

Conclusion:  In apparently healthy subjects with normal renal function, retinal arteriolar and venular calibers were negatively correlated with kidney function, suggesting common determinants of these preclinical target organ damages.
Leptin and adiponectin in cord blood from children of normal weight, overweight and obese mothers
Authors: Brynhildsen Jan , Sydsjö Gunilla , Blomberg Marie , Claesson Ing‐Marie , Theodorsson Elvar , Nyström Fredrik , Sydsjö Adam , Josefsson Ann
Published: February 2013

Aim

To study cord blood concentrations of adiponectin and leptin in children born by normal weight, overweight and obese mothers and to study these parameters in relation to a weight gain intervention programme for obese mothers.

Methods

Ten millilitre cord blood was collected and analysed for leptin and adiponectin concentrations in children with gestational age >37 weeks born by 60 normal weight, 45 overweight and 145 obese mothers. 82 obese mothers took part in a weight gain intervention programme.

Results

Concentrations of leptin and adiponectin were higher in cord blood from children of overweight and obese mothers compared with children of normal weight mothers (leptin: Md 13.2, 30, 3 and 90.2 ng/mL respectively, p < 0.001; adiponectin 35.9, 205.4, 213.8 ng/L p < 0.001). No differences were found between overweight and obese mothers.

The weight gain intervention programme for obese pregnant women had significant effects on the weight gain during pregnancy but had no effects on cord blood serum concentrations of leptin and adiponectin.

Conclusion

Cord blood leptin and adiponectin concentrations were higher in children born by overweight or obese women compared with children of normal weight mothers. A weight gain intervention programme for obese pregnant women did not affect these results. Intrauterine exposition to high concentrations of leptin and adiponectin may play a role in weight development later in life.
Pattern of serotonin‐like immunoreactive cells in scyphozoan and hydrozoan planulae and their relation to settlement
Authors: Mayorova Tatiana , Kach Jacob , Kosevich Igor
Published: February 2013

The planulae of almost all investigated cnidarian species possess neuron‐like cells. The distribution of these cells is usually uneven throughout the long axis of the planula. The majority of these cells are located in the anterior half of the planula body. Scyphozoan planulae, as well as anthozoan planulae, have a sensory structure at the anterior pole called an apical organ, which is believed to take part in metamorphosis induction. Hydrozoan planulae also possess sensory cells. It has been previously shown in several cnidarian larvae that their neuronal cells contain the neurotransmitter, serotonin. The present study describes the peculiarities of serotonin‐like immunoreactive cells in Aurelia aurita (Scyphozoa) and Gonothyraea loveni (Hydrozoa) planulae. We show that several cells in the presumptive apical organ of A. aurita are immunoreactive to antibodies against serotonin, while G. loveni planulae have an accumulation of serotonin‐positive cells near the anterior pole. Additional serotonin‐like immunoreactive cells are found in the lateral ectoderm of both planulae. Treatment of A. aurita and G. loveni planulae with serotonin or its blockers show that serotonin is likely involved in the initiation of planula settlement.
Distributed Lag Models for Hydrological Data
Authors: Rushworth Alastair M. , Bowman Adrian W. , Brewer Mark J. , Langan Simon J.
Published: February 2013

The distributed lag model (DLM), used most prominently in air pollution studies, finds application wherever the effect of a covariate is delayed and distributed through time. We specify modified formulations of DLMs to provide computationally attractive, flexible varying‐coefficient models that are applicable in any setting in which lagged covariates are regressed on a time‐dependent response. We investigate the application of such models to rainfall and river flow and in particular their role in understanding the impact of hidden variables at work in river systems. We apply two models to data from a Scottish mountain river, and we fit to some simulated data to check the efficacy of our model approach. During heavy rainfall conditions, changes in the influence of rainfall on flow arise through a complex interaction between antecedent ground wetness and a time‐delay in rainfall. The models identify subtle changes in responsiveness to rainfall, particularly in the location of peak influence in the lag structure.
Adolescent loneliness and psychiatric morbidity in Northern Ireland
Authors: Shevlin Mark , Murphy Siobhan , Mallett John , Stringer Maurice , Murphy Jamie
Published: February 2013

Objective

Previous research has identified an association between loneliness and psychiatric morbidity, but many of the studies have been based on small convenience samples and have not always used standardized measures.

Aims and Methods

This study aimed to assess the association between standardized measures of loneliness and psychiatric morbidity using data from a large sample of adolescents from Northern Ireland (Young Life and Times Survey, 2011). A total of 1,434 participants completed the survey.

Results

The prevalence of loneliness and psychiatric morbidity was 15.6% and 28.4% respectively. A multivariate binary logistic regression was used to identify the significant correlates of psychiatric morbidity. Demographic and loneliness variables were entered as covariates and female gender and perceptions of familial poverty were significantly associated with GHQ caseness. Loneliness increased the likelihood of GHQ caseness by more than five times.

Conclusions

Adolescent loneliness is significantly associated with psychiatric morbidity for Northern Irish adolescents. School‐based screening and interventions to reduce loneliness may reduce the prevalence of loneliness.

Practitioner Points

Adolescent loneliness is a possible indirect indicator for mental health problems.

Standardized measures of loneliness, with population norms, are widely available.

There is no clear profile of a ‘lonely adolescent’ based on demographic variables.