bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographic variation in range size and beta diversity of groundwater crustaceans: insights from habitats with low thermal seasonality
Authors: Zagmajster Maja , Eme David , Fišer Cene , Galassi Diana , Marmonier Pierre , Stoch Fabio , Cornu Jean‐François , Malard Florian
Published: June 2014

Aim

Three broad mechanisms have been proposed to explain geographic variation in species range size: habitat area/heterogeneity, climate seasonality and long‐term climate variability. However, it has proved difficult to disentangle their relative role, particularly as temperature seasonality often covaries with the amplitude of long‐term temperature oscillations. Here, we shed new light onto this debate by providing the first continental‐scale analysis of range size and beta diversity in groundwater habitats, where taxa are not exposed to latitudinal variation in temperature seasonality.

Location

Europe.

Methods

We compiled and mapped occurrence data for 1570 groundwater crustacean species. Generalized regression models were used to test for latitudinal variation in geographic range size and to assess the relative role of the three broad mechanisms in shaping present‐day patterns of range size. We partitioned beta diversity into its spatial turnover and nestedness components and analysed their latitudinal variation across Europe.

Results

Median range size increases with latitude above 43° N and the range size of individual species is positively correlated to latitude, even after accounting for phylogenetic effects. Long‐term temperature variability accounted for a substantially higher variation in median range size of groundwater crustaceans across Europe than precipitation seasonality and habitat heterogeneity, including aquifer area, elevation range, climatic rarity and productive energy. Spatial turnover contributes significantly more to beta diversity in southern regions characterized by stable historic climates than it does in northern Europe.

Main conclusions

Our findings add support to the historic climate hypothesis which suggests that patterns of increasing range size and decreasing species turnover at higher latitudes in the Palaearctic region are primarily driven by long‐term temperature oscillations rather than by climatic seasonality and the availability and heterogeneity of habitats.
Analytic Element Modeling of Steady Interface Flow in Multilayer Aquifers Using AnAqSim
Authors: Fitts Charles R. , Godwin Joshua , Feiner Kathleen , McLane Charles , Mullendore Seth
Published: June 2014

This paper presents the analytic element modeling approach implemented in the software AnAqSim for simulating steady groundwater flow with a sharp fresh‐salt interface in multilayer (three‐dimensional) aquifer systems. Compared with numerical methods for variable‐density interface modeling, this approach allows quick model construction and can yield useful guidance about the three‐dimensional configuration of an interface even at a large scale. The approach employs subdomains and multiple layers as outlined by Fitts (2010) with the addition of discharge potentials for shallow interface flow (Strack 1989). The following simplifying assumptions are made: steady flow, a sharp interface between fresh‐ and salt water, static salt water, and no resistance to vertical flow and hydrostatic heads within each fresh water layer. A key component of this approach is a transition to a thin fixed minimum fresh water thickness mode when the fresh water thickness approaches zero. This allows the solution to converge and determine the steady interface position without a long transient simulation. The approach is checked against the widely used numerical codes SEAWAT and SWI/MODFLOW and a hypothetical application of the method to a coastal wellfield is presented.
Developing a long‐term condition's information service in collaboration with third sector organisations
Authors: McShane Lesley , Greenwell Kate , Corbett Sally , Walker Richard
Published: June 2014

Background

People with long‐term conditions need to be signposted to high quality information and advice to understand and manage their condition. Information seeking tools combined with third sector information could help address their information needs.

Objective

To describe the development and implementation of an information service for people living with long‐term conditions at one NHS acute trust in the Northeast of England.

Methods

An information service was trialled using bespoke information models for three long‐term conditions in collaboration with third sector organisations. These guided people to relevant, timely and reliable information. Both clinician and service user questionnaires were used to evaluate satisfaction with the service.

Results

Appropriately designed information models can be used interchangeably across all services. Between 75% and 91% of users agreed that they were satisfied with various aspects of the service. Generally, users received relevant, understandable and high quality information at the right time. Nearly all health professionals (94–100%) felt the service was accessible, provided high quality information and did not significantly impact on their consultation time.

Conclusion

The developed information service was well received by service users and health professionals. Specifically, the use of information prescriptions and menus facilitated access to information for people with long‐term conditions.
Current concepts in the management of prosthetic joint infection
Authors: Aboltins C. , Daffy J. , Choong P. , Stanley P.
Published: June 2014

Prosthetic joint infection (PJI) is a serious complication of arthroplasty that is associated with significant mortality, morbidity and costs. PJI is difficult to cure because causative bacteria form and persist in biofilm adherent to the prosthesis surface. PJI can be classified into early, delayed or late according to the time of onset after insertion of the prosthesis, and this classification can help determine pathogenesis and appropriate management. Traditional treatment has been with prolonged intravenous antibiotics and prosthesis exchange, which has been successful in treating infection but is technically difficult and has high rates of associated morbidity. On the basis of in vitro and animal studies, interest has turned to the use of antimicrobials that are particularly active against biofilm‐associated bacteria. Recent clinical evidence shows success in more than 77% of early PJI with surgical debridement, retention of prosthesis and the use of rifampicin‐based combinations for staphylococcal PJI. Fluoroquinolones are preferred for Gram‐negative PJI. Optimal antimicrobial treatment duration and the management of polymicrobial, enterococcal, fungal and culture‐negative infections are still yet to be defined but will become more clear as the results of current research comes to hand.
General practitioner management plans delaying time to next potentially preventable hospitalisation for patients with heart failure
Authors: Vitry A. I. , Nguyen T. A. , Ramsay E. N. , Caughey G. E. , Gilbert A. L. , Shakib S. , Ryan P. , Esterman A. , McDermott R. A. , Roughead E. E.
Published: June 2014

Background

Several studies have shown that the Australian Medicare‐funded chronic disease management programme can lead to improvements in care processes. No study has examined the impact on long‐term health outcomes.

Aims

This retrospective cohort study assessed the association between provision of a general practitioner management plan and time to next potentially preventable hospitalisation for older patients with heart failure.

Methods

We used the Australian Government Department of Veterans' Affairs (DVA) claims database and compared patients exposed to a general practitioner management plan with those who did not receive the service. Kaplan–Meier analysis and Cox proportional hazards models were used to compare time until next potentially preventable hospitalisation for heart failure between the exposed and unexposed groups.

Results

There were 1993 patients exposed to a general practitioner management plan and 3986 unexposed patients. Adjusted results showed a 23% reduction in the rate of potentially preventable hospitalisation for heart failure at any time (adjusted hazard ratio, 0.77; 95% confidence interval, 0.64 to 0.92; P = 0.0051) among those with a general practitioner management plan compared with the unexposed patients. Within one year, 8.6% of the exposed group compared with 10.7% of the unexposed group had a potentially preventable hospitalisation for heart failure.

Conclusions

A general practitioner management plan is associated with delayed time to next potentially preventable hospitalisation for heart failure.
Conjugated bilirubin affects cytokine profiles in hepatitis A virus infection by modulating function of signal transducer and activator of transcription factors
Authors: Castro‐García Flor P. , Corral‐Jara Karla F. , Escobedo‐Melendez Griselda , Sandoval‐Hernandez Monserrat A. , Rosenstein Yvonne , Roman Sonia , Panduro Arturo , Fierro Nora A.
Published: June 2014

Hepatitis A virus (HAV) infection is the major cause of acute liver failure in paediatric patients. The clinical spectrum of infection is variable, and liver injury is determined by altered hepatic enzyme function and bilirubin concentration. We recently reported differences in cytokine profiles between distinct HAV‐induced clinical courses, and bilirubin has been recognized as a potential immune‐modulator. However, how bilirubin may affect cytokine profiles underlying the variability in the course of infection has not been determined. Herein, we used a transcription factor (TF) binding site identification approach to retrospectively analyse cytokine expression in HAV‐infected children and to predict the entire set of TFs associated with the expression of specific cytokine profiles. The results suggested that modulation of the activity of signal transducers and activators of transcription proteins (STATs) may play a central role during HAV infection. This led us to compare the degree of STAT phosphorylation in peripheral blood lymphoid cells (PBLCs) from paediatric patients with distinct levels of conjugated bilirubin (CB). Low CB levels in sera were associated with increased STAT‐1 and STAT‐5 phosphorylation. A positive correlation was observed between the serum interleukin‐6 (IL‐6) content and CB values, whereas higher levels of CB correlated with reduced serum IL‐8 values and with a reduction in the proportion of PBLCs positive for STAT‐5 phosphorylation. When CB was used to stimulate patients' PBLCs in vitro, the levels of IL‐6 and tumour necrosis factor‐α were increased. The data showed that bilirubin plays a role in STAT function and affects cytokine profile expression during HAV infection.
Selective immunotargeting of diabetogenic CD4 T cells by genetically redirected T cells
Authors: Perez Shira , Fishman Sigal , Bordowitz Amos , Margalit Alon , Wong F. Susan , Gross Gideon
Published: June 2014

The key role played by islet‐reactive CD8 and CD4 T cells in type 1 diabetes calls for new immunotherapies that target pathogenic T cells in a selective manner. We previously demonstrated that genetically linking the signalling portion of CD3‐ζ onto the C‐terminus of β2‐microglobulin and an autoantigenic peptide to its N‐terminus converts MHC‐I complexes into functional T‐cell receptor‐specific receptors. CD8 T cells expressing such receptors specifically killed diabetogenic CD8 T cells, blocked T‐cell‐induced diabetes in immunodeficient NOD.SCID mice and suppressed disease in wild‐type NOD mice. Here we describe the immunotargeting of CD4 T cells by chimeric MHC‐II receptors. To this end we chose the diabetogenic NOD CD4 T‐cell clone BDC2.5, which recognizes the I‐Ag7‐bound 1040‐31 mimotope. We assembled several constructs encoding I‐Ag7 α‐ and β‐chains, the latter carrying mim or hen egg lysozyme peptide as control, each supplemented with CD3‐ζ intracellular portion, either with or without its transmembrane domain. Following mRNA co‐transfection of reporter B3Z T cells and mouse CD8 and CD4 T cells, these constructs triggered robust activation upon I‐Ag7 cross‐linking. A BDC2.5 T‐cell hybridoma activated B3Z transfectants expressing the mimotope, but not the control peptide, in both configurations. Potent two‐way activation was also evident with transgenic BDC2.5 CD4 T cells, but peptide‐specific activation required the CD3‐ζ transmembrane domain. Chimeric MHC‐II/CD3‐ζ complexes therefore allow the selective immunotargeting of islet‐reactive CD4 T cells, which take part in the pathogenesis of type 1 diabetes.
Low‐Temperature Sintering Li2MoO4/Ni0.5Zn0.5Fe2O4 Magneto‐Dielectric Composites for High‐Frequency Application
Authors: He Li , Zhou Di , Yang Haibo , Niu Yujuan , Xiang Feng , Wang Hong
Published: June 2014

The coexistence of Li2MoO4 (LMO) and Ni0.5Zn0.5Fe2O4 (NZO) has been proven and their low‐temperature‐sintered magneto‐dielectric composites (1−x)LMO–xNZO (volume fraction factor x = 0.1, 0.3, 0.5, 0.7) were prepared by the conventional solid‐state reaction method and were sintered below 700°C. It is found that the optimal sample (x = 0.5) has good and relatively stable magneto‐dielectric performance in the frequency range from 10 MHz to 1 GHz with permittivity between 7.14 and 6.84, dielectric loss tangent between 0.09 and 0.02, and permeability between 5.23 and 3.30, magnetic loss tangent between 0.06 and 0.65, respectively. Furthermore, the verified chemical compatibility with silver indicates that the LMO–NZO ceramics are potential for low‐temperature cofired ceramic application and their multifunctional magneto‐dielectric properties also make them for potential applications in electronic devices.
Historical patterns of oak population expansion in the Chautauqua Hills, Kansas
Authors: Rogers Thomas R. , Russell F. Leland
Published: June 2014

Aim

Rates of tree population expansion have increased in many North American landscapes that were mosaics of grasslands, savannas and woodlands historically. Consequences of woodland expansion include reduced economic return from grazing and changes in native biodiversity, but causes of woodland expansion are poorly understood. We address historical timing of blackjack oak (Quercus marilandica) and post oak (Quercus stellata) population expansion in tree–grass ecosystems, roles of climate and land use in driving this expansion, and future stability of these woodlands.

Location

The Cross Timbers ecosystem in Kansas, USA.

Methods

Using increment cores, we quantified blackjack oak and post oak age structures in four woodlands on sites that were not wooded in the 1860s. We compared timing of oak regeneration with climate fluctuations (using the Palmer drought severity index) and land‐use history. We quantified tree species composition within 5‐m radii of sampled oaks.

Results

Recruitment of both oak species increased between 1925 and 1945. Modal age classes recruited from 1935 to 1960. Recruitment was associated with dry intervals at the two sites with north‐ or east‐facing aspects. This association was driven by blackjack oak recruitment in dry intervals. Woodlands on the sites with south‐ and west‐facing aspects contained only oaks, whereas those on the sites with north‐ and east‐facing aspects contained saplings of fire‐intolerant, shade‐tolerant tree species.

Main conclusions

Our results contribute to growing evidence for woodland expansion in the region during dry climate intervals. The association between drought and recruitment was influenced by slope aspect and was more pronounced in the less fire‐tolerant oak species. Although woodland expansion coincided with regional increases in fire frequency, drought and greater use of prescribed burning are likely to have reduced fire intensities by reducing fuel loads. These oak woodlands, which have developed during the 20th century, appear to form stable communities on xeric slopes but to be undergoing succession towards a mesophytic tree community on mesic slopes.
Impact of hemoglobin A1c‐based criterion on diagnosis of prediabetes: The Korea National Health and Nutrition Examination Survey 2011
Authors: Kim Chul‐Hee , Kim Hong‐Kyu , Kim Bo‐Yeon , Jung Chan‐Hee , Mok Ji‐Oh , Kang Sung‐Koo
Published: June 2014

To examine the impact of hemoglobin A1c (HbA1c) criterion on the diagnosis of prediabetes in Koreans, we analyzed nationally representative cross‐sectional data of 5,845 Korean adults aged ≥20 years from the Fifth Korea National Health and Nutrition Examination Survey 2011. Standardized prevalence rates of prediabetes in Korean adults by fasting plasma glucose (FPG; 5.6–6.9 mmol/L), HbA1c (5.7–6.4% [39–46 mmol/mol]), and combined criteria were 16.9, 28.4 and 33.8%, respectively. Among the subjects with prediabetes, 16% met FPG criteria only, 55% met HbA1c criteria only and 29% met both criteria. Prediabetic subjects who met HbA1c criteria only were significantly older, more likely to be women, and had lower hemoglobin and serum iron concentrations, whereas those who met FPG criteria only had higher body mass index, waist circumference, systolic and diastolic blood pressure. In conclusion, introduction of HbA1c criterion markedly increased the prevalence of prediabetes in Koreans, and the two criteria identified people with different characteristics.
Nematodes associated with the double‐spined bark beetleIps duplicatus(Coleoptera:Curculionidae) in centralEurope
Authors: Grucmanová Š. , Holuša J. , Nermut' J.
Published: June 2014

Ips duplicatus(Sahlberg) is an important forest pest in centralEurope, but its nematode associates have seldom been studied. Therefore, nematodes associated withI. duplicatuswere determined at three localities in theCzechRepublic. The percentage of beetles with phoretic nematodes ranged from 18 to 65%.Micoletzkya buetschliiand other phoretic nematodes were found under elytra, on wings, and between body segments. The percentage of beetles with nematodes in the haemocoel ranged from 3 to 30%, and the nematodes includedContortylenchus diplogasterandParasitylenchuscf.aculeatus. Juveniles ofParasitorhabditis obtusa(Fuchs 1915) were found in the intestines of 0–16% of the beetles. The most abundant species inI. duplicatusgalleries wereP. obtusaandM. buetschlii. Cryptaphelenchussp.,Parasitaphelenchussp. and unidentified tylenchid juveniles also were found in the galleries. The percentage of beetles with nematodes was greater in the overwintering than in the offspring generation, and numbers of nematodes per gallery increased with gallery development.
Royal College of Physicians Intercollegiate Stroke Working Party evidence‐based guidelines for the secondary prevention of stroke through nutritional or dietary modification
Authors: Hookway C. , Gomes F. , Weekes C. E.
Published: June 2014

Background

Each year, 15 million people worldwide and 110 000 people in England have a stroke. Having a stroke increases the risk of having another. There are a number of additional known risk factors that can be modified by diet. The present study aimed to systematically review key nutrients and diets and their role in secondary prevention, as well as provide evidence‐based guidelines for use in clinical practice. The work was conducted as part of the process to develop the 4th edition of the Royal College of Physicians' (RCP) National Clinical Guideline (NCG) for Stroke.

Methods

Questions were generated by the research team, in consultation with the Virtual Stroke Group, an online professional interest group, and the RCP Intercollegiate Stroke Working Party Guideline Development Group. Nine questions covering several individual nutrients and diet combinations were defined and searches conducted up until 31 October 2011 using five electronic databases (Embase, Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Library and Web of Science). All included studies were assessed for quality and risk of bias using van Tulder criteria for randomised controlled trials (RCTs) and Quality of Reporting of Meta‐analyses (QUORUM) criteria for systematic reviews.

Results

Of 4287 abstracts were identified, 79 papers were reviewed and 29 systematic reviews and RCTs were included to provide evidence for the secondary prevention components of the guidelines. For each question, evidence statements, recommendations and practical considerations were developed.

Conclusions

This systematic review process has resulted in the development of evidence‐based guidelines for use in clinical practice and has identified areas for further research.
Interprofessional collaboration at transition of care: perspectives of child and family health nurses and midwives
Authors: Psaila Kim , Schmied Virginia , Fowler Cathrine , Kruske Sue
Published: June 2014

Aims and objectives

To examine collaboration in the provision of universal health services for children and families in Australia from the perspective of midwives and child health and family health nurses.

Background

Collaboration is identified as a key concept contributing to families' smooth transition between maternity and child health services. However, evidence suggests that collaboration between services is often lacking. Few studies have explored how maternity and child health and family health services or professionals collaborate to facilitate a smooth transition.

Design

This study reports on data collected in phases 1 and 2 of a three‐phase mixed‐methods study investigating the feasibility of implementing a national approach to child health and family health services in Australia (Child Health: Researching Universal Services study).

Methods

In phase 1, consultations (via discussion groups, focus groups and teleconferences) were held with 45 midwives and 60 child health and family health nurses. Themes identified were used to develop phase 2 surveys. In phase 2, 1098 child health and family health nurses and 655 midwives returned surveys.

Results

Midwives and child health and family health nurses reported ‘some collaboration’. Midwives and child health and family health nurses indicated that collaboration was supported by having agreement on common goals and recognising and valuing the contributions of others. Organisational barriers such as poor communication and information transfer processes obstructed relationships. Good collaboration was reported more frequently when working with other professionals (such as allied health professionals) to support families with complex needs.

Conclusion

This study provides information on the nature and extent of collaboration from the perspective of midwives and child health and family health nurses providing universal health services for children and families.

Relevance to clinical practice

Both professional groups emphasised the impact of service disconnection on families. However, their ability to negotiate professional differences is affected by system constraints and differing perspectives of what constitutes collaboration. Developing the capacity to collaborate is essential to ensure smooth transition of care given ongoing changes to the system.
Melatonin identified in meats and other food stuffs: potentially nutritional impact
Authors: Tan Dun‐Xian , Zanghi Brian M. , Manchester Lucien C. , Reiter Russel J.
Published: June 2014

Melatonin has been identified in primitive photosynthetic bacteria, fungi, plants, and animals including humans. Vegetables, fruits, cereals, wine, and beers all contain melatonin. However, the melatonin content in meats has not been reported previously. Here, for the first time, we report melatonin in meats, eggs, colostrum, and in other edible food products. The levels of melatonin measured by HPLC, in lamb, beef, pork, chicken, and fish, are comparable to other food stuffs (in the range of ng/g). These levels are significantly higher than melatonin concentrations in the blood of vertebrates. As melatonin is a potent antioxidant, its presence in the meat could contribute to shelf life duration as well as preserve their quality and taste. In addition, the consumption of these foods by humans or animals could have health benefits considering the important functions of melatonin as a potent free radical scavenger and antioxidant.
The impact of antihyperlipidemic drugs on the viral load of patients with chronic hepatitis C infection: a meta‐analysis
Authors: Grammatikos G. , Farnik H. , Bon D. , Böhlig A. , Bader T. , Berg T. , Zeuzem S. , Herrmann E.
Published: June 2014

Several studies investigating the role of statins and fibrates in chronic hepatitis C virus (HCV) infection offered so far conflicting evidence regarding the antiviral potency of these medications, whereas combination of these drugs with pegylated interferon and ribavirin improved in some trials therapeutic outcome. We conducted a literature search to identify trials that included monoinfected HCV patients, treated with statins or fibrates as monotherapy with the primary end point of our meta‐analysis being the quantitative change of HCV‐RNA induced by these medications. Logarithmic changes of the viral load (ΔlogVL) and confidence intervals (CIs) were calculated according to the DerSimonian‐Laird estimate. Statistical heterogeneity was assessed with the I² statistic. We identified eight observational studies that evaluated the potency of bezafibrate and different statins as monotherapy to induce a significant reduction of HCV‐RNA in HCV‐monoinfected patients (n = 281). Overall, a significant reduction of viral load with mean 0.19 [log10 IU/mL] (95%‐confidence interval, (CI) 0.11–0.28) could be observed when antihyperlipidemic medications were administered. Bezafibrate featured the highest antiviral efficacy (0.45 log10 reduction, 95%‐CI, 0.17–0.72) among all medications and fluvastatin (0.20 log10 reduction, 95%‐CI, 0.09–0.31) among all statins tested. Based on meta‐analysis, fibrates and statins induce a reduction of HCV viral load. We suggest that the addition of statins and fibrates to antiviral regimes, especially in HCV patients with concomitant dyslipidemia, could beside the established reduction of cardiovascular risk increase the potency of antiviral therapy.
Creating new evolutionary pathways through bioinvasion: the population genetics of brushtail possums in New Zealand
Authors: Sarre Stephen D. , Aitken Nicola , Adamack Aaron T. , MacDonald Anna J. , Gruber Bernd , Cowan Phil
Published: June 2014

Rapid increases in global trade and human movement have created novel mixtures of organisms bringing with them the potential to rapidly accelerate the evolution of new forms. The common brushtail possum (Trichosurus vulpecula), introduced into New Zealand from Australia in the 19th century, is one such species having been sourced from multiple populations in its native range. Here, we combine microsatellite DNA‐ and GIS‐based spatial data to show that T. vulpecula originating from at least two different Australian locations exhibit a population structure that is commensurate with their introduction history and which cannot be explained by landscape features alone. Most importantly, we identify a hybrid zone between the two subspecies which appears to function as a barrier to dispersal. When combined with previous genetic, morphological and captive studies, our data suggest that assortative mating between the two subspecies may operate at a behavioural or species recognition level rather than through fertilization, genetic incompatibility or developmental inhibition. Nevertheless, hybridization between the two subspecies of possum clearly occurs, creating the opportunity for novel genetic combinations that would not occur in their natural ranges and which is especially likely given that multiple contact zones occur in New Zealand. This discovery has implications for wildlife management in New Zealand because multiple contact zones are likely to influence the dispersal patterns of possums and because differential susceptibility to baiting with sodium fluoroacetate between possums of different origins may promote novel genetic forms.
Differential high‐altitude adaptation and restricted gene flow across a mid‐elevation hybrid zone in Andean tit‐tyrant flycatchers
Authors: DuBay Shane G. , Witt Christopher C.
Published: June 2014

The tropical Andes are a global hotspot of avian diversity that is characterized by dramatic elevational shifts in community composition and a preponderance of recently evolved species. Bird habitats in the Andes span a nearly twofold range of atmospheric pressure that poses challenges for respiration, thermoregulation, water balance and powered flight, but the extent to which physiological constraints limit species' elevational distributions is poorly understood. We report a previously unknown hybrid zone between recently diverged flycatchers (Aves, Tyrannidae) with partially overlapping elevational ranges. The southern Anairetes reguloides has a broad elevational range (0–4200 m), while the northern Anairetes nigrocristatus is restricted to high elevations (>2200 m). We found hybrids in central Peru at elevations between ~3100 and 3800 m, with A. nigrocristatus above this elevation and A. reguloides below. We analysed variation in haematology, heart mass, morphometrics, plumage and one mitochondrial and three nuclear loci across an elevational transect that encompasses the hybrid zone. Phenotypic traits and genetic markers all showed steep clines across the hybrid zone. Haemoglobin concentration, haematocrit, mean cellular haemoglobin concentration and relative heart mass each increased at altitude more strongly in A. reguloides than in A. nigrocristatus. These findings suggest that A. nigrocristatus is more resistant than A. reguloides to high‐altitude hypoxic respiratory stress. Considering that the ancestor of the genus is suggested to have been restricted to high elevations, A. reguloides may be secondarily adapted to low altitude. We conclude that differential respiratory specialization on atmospheric pressure combined with competitive exclusion maintains replacement along an elevational contour, despite interbreeding.
Lipochitooligosaccharide recognition: an ancient story
Authors: Liang Yan , Tóth Katalin , Cao Yangrong , Tanaka Kiwamu , Espinoza Catherine , Stacey Gary
Published: June 2014

Chitin is the second most abundant polysaccharide in nature, found in crustacean shells, insect exoskeletons and fungal cell walls. The action of chitin and chitin derivatives on plants has become a very interesting story of late. Chitin is a β1‐4‐linked polymer of N‐acetyl‐d‐glucosamine (GlcNAc). In this unmodified form, chitooligosaccharides (degree of polymerization (dp) = 6–8)) are strong inducers of plant innate immunity. By contrast, when these chitooligosaccharides are acylated (so‐called lipochitooligosaccharides, LCOs) and further modified, they can act as Nod factors, the key signaling molecules that play an important role in the initiation of the legume–rhizobium symbiosis. In a similar form, these molecules can also act as Myc factors, the key signaling molecules involved in the arbuscular mycorrhizal (AM) symbiosis. It has been proposed that Nod factor perception might have evolved from the more ancient AM symbiosis. Increasing evidence now suggests that LCO perception might have evolved from plant innate immunity signaling. In this review, we will discuss the evolutionary origin of symbiotic LCO recognition.
PHYTOALEXIN DEFICIENT 4 affects reactive oxygen species metabolism, cell wall and wood properties in hybrid aspen (Populus tremula L. × tremuloides)
Authors: ŚLESAK IRENEUSZ , SZECHYŃSKA‐HEBDA MAGDALENA , FEDAK HALINA , SIDORUK NATALIA , DĄBROWSKA‐BRONK JOANNA , WITOŃ DAMIAN , RUSACZONEK ANNA , ANTCZAK ANDRZEJ , DROŻDŻEK MICHAŁ , KARPIŃSKA BARBARA , KARPIŃSKI STANISŁAW
Published: June 2014

The PHYTOALEXIN DEFICIENT 4 (PAD4) gene in Arabidopsis thaliana (AtPAD4) is involved in the regulation of plant – pathogen interactions. The role of PAD4 in woody plants is not known; therefore, we characterized its function in hybrid aspen and its role in reactive oxygen species (ROS)‐dependent signalling and wood development. Three independent transgenic lines with different suppression levels of poplar PAD expression were generated. All these lines displayed deregulated ROS metabolism, which was manifested by an increased H2O2 level in the leaves and shoots, and higher activities of manganese superoxide dismutase (MnSOD) and catalase (CAT) in the leaves in comparison to the wild‐type plants. However, no changes in non‐photochemical quenching (NPQ) between the transgenic lines and wild type were observed in the leaves. Moreover, changes in the ROS metabolism in the pad4 transgenic lines positively correlated with wood formation. A higher rate of cell division, decreased tracheid average size and numbers, and increased cell wall thickness were observed. The results presented here suggest that the Populus tremula × tremuloides PAD gene might be involved in the regulation of cellular ROS homeostasis and in the cell division – cell death balance that is associated with wood development.
Comparison of the response to phosphorus deficiency in two lupin species, Lupinus albus and L. angustifolius, with contrasting root morphology
Authors: FUNAYAMA‐NOGUCHI SACHIKO , NOGUCHI KO , TERASHIMA ICHIRO
Published: June 2014

White lupin (Lupinus albus) produces cluster roots, an adaptation to low soil phosphorus (P). Cluster roots exude large levels of P‐solubilizing compounds such as citrate and malate. In contrast, narrow leaf lupin (L. angustifolius) is closely related to L. albus, but does not produce cluster roots. To examine the different strategies for P acquisition, we compared the growth, biomass allocation, respiratory properties and construction cost between L. albus and L. angustifolius under P‐deficient conditions. Both Lupinus species were grown in hydroponic culture with 1 or 100 μM P. Under the P‐deficient regime, L. albus produced cluster roots with little change in biomass allocation, while L. angustifolius significantly increased biomass allocation to roots. The rate of cyanide‐resistant SHAM (salicylhydroxamic acid)‐sensitive respiration was high in cluster roots and very low in roots of L. angustifolius. These results suggest a low alternative oxidase (AOX) activity in L. angustifolius roots, and thus, ATP would be produced efficiently in L. angustifolius roots. The construction cost was highest in cluster roots and lowest in L. angustifolius roots. This study shows that under P deficiency, L. albus produces high‐cost cluster roots to increase the P availability, while L. angustifolius produces large quantities of low‐cost roots to enhance P uptake.
Relative impact of mateversuspollinator availability on pollen limitation and outcrossing rates in a mass‐flowering species
Authors: Delmas C. E. L. , Escaravage N. , Cheptou P‐O. , Charrier O. , Ruzafa S. , Winterton P. , Pornon A.
Published: June 2014

Plant mating systems are driven by several pre‐pollination factors, including pollinator availability, mate availability and reproductive traits. We investigated the relative contributions of these factors to pollination and to realized outcrossing rates in the patchily distributed mass‐flowering shrubRhododendron ferrugineum. We jointly monitored pollen limitation (comparing seed set from intact and pollen‐supplemented flowers), reproductive traits (herkogamy, flower size and autofertility) and mating patterns (progeny array analysis) in 28 natural patches varying in the level of pollinator availability (flower visitation rates) and of mate availability (patch floral display estimated as the total number of inflorescences per patch). Our results showed that patch floral display was the strongest determinant of pollination and of the realized outcrossing rates in this mass‐flowering species. We found an increase in pollen limitation and in outcrossing rates with increasing patch floral display. Reproductive traits were not significantly related to patch floral display, while autofertility was negatively correlated to outcrossing rates. These findings suggest that mate limitation, arising from high flower visitation rates in small plant patches, resulted in low pollen limitation and high selfing rates, while pollinator limitation, arising from low flower visitation rates in large plant patches, resulted in higher pollen limitation and outcrossing rates. Pollinator‐mediated selfing and geitonogamy likely alleviates pollen limitation in the case of reduced mate availability, while reduced pollinator availability (intraspecific competition for pollinator services) may result in the maintenance of high outcrossing rates despite reduced seed production.
Pilot‐scale comparison of four duckweed strains from different genera for potential application in nutrient recovery from wastewater and valuable biomass production
Authors: Zhao Y. , Fang Y. , Jin Y. , Huang J. , Bao S. , Fu T. , He Z. , Wang F. , Wang M. , Zhao H.
Published: June 2014

The application potential of four duckweed strains from four genera, Wolffia globosa 0222, Lemna japonica 0223, Landoltia punctata 0224 and Spirodela polyrhiza 0225, were compared in four parallel pilot‐scale wastewater treatment systems for more than 1 year. The results indicated that each duckweed strain had unique potential advantages. Unlike L. japonica 0223 and La. punctata 0224, which grow throughout the year, S. polyrhiza 0225 and W. globosa 0222 do not survive cold weather. For year round performance, L. japonica 0223 was best not only in dry biomass production (6.10 g·m−2·day−1), but also in crude protein (35.50%), total amino acid (26.83%) and phosphorus (1.38%) content, plus recovery rates of total nitrogen (TN), total phosphorus (TP) and CO2 (0.31, 0.085 and 7.76 g·m−2·day−1, respectively) and removal rates of TN and TP (0.66 and 0.089 g·m−2·day−1, respectively). This strongly demonstrates that L. japonica 0223 performed best in wastewater treatment and protein biomass production. Under nutrient starvation conditions, La. punctata 0224 had the highest starch content (45.84%), dry biomass production (4.81 g·m−2·day−1) and starch accumulation (2.9 g·m−2·day−1), making it best for starch biomass production. W. globosa 0222 and S. polyrhiza 0225 showed increased flavonoid biomass production, with higher total flavonoid content (5.85% and 4.22%, respectively) and high dominant flavonoids (>60%). This study provides useful information for selecting the appropriate local duckweed strains for further application in wastewater treatment and valuable biomass production.
Zeatin modulates flower bud development and tocopherol levels in Cistus albidus (L.) plants as they age
Authors: Hernández I. , Miret J. A. , Van Der Kelen K. , Rombaut D. , Van Breusegem F. , Munné‐Bosch S.
Published: June 2014

In a previous study we showed that Cistus albidus (L.) experiences an age‐dependent decay in flower vigour correlated with a decline in trans‐zeatin (tZ) levels. In the present study we aimed to establish a causal relationship between these two phenomena. Exogenous tZ applied to plants grown under semi‐controlled conditions did not rescue flower vigour; however, it accelerated flower development, but only in younger individuals. Older plants showed lower tocopherol levels in flower buds, which were restored by exogenous tZ, suggesting that a loss of antioxidant defences may underlie the age‐dependent decay in flower vigour. We conclude that declining tZ levels may not be directly responsible for the age‐associated loss of floral vigour; that tZ modulates the speed of flower development as plants age; and that flower buds alter their sensitivity to tZ as plants age.
Limited evolutionary divergence of seedlings after the domestication of plant species
Authors: Milla R. , Morente‐López J.
Published: June 2014

The most vulnerable stage in the life of plants is the seedling. The transition from wild to agricultural land that plants experienced during and after domestication implied a noticeable change in the seedlings′ environment. Building on current knowledge of seedling ecology, and on previous studies of cassava, we hypothesise that cultivation should have promoted epigeal germination of seedlings, and more exposed and photosynthetic cotyledons. To test this hypothesis, we phenotyped seedling morpho‐functional traits in a set of domesticated and wild progenitor accessions of 20 Eudicot herbaceous crop species. Qualitative traits like epi‐ versus hypogeal germination, leafy versus storage type of cotyledons, or crypto‐ versus phanerocotyledonar germination, remained conserved during the domestication of all 20 species. Lengths of hypocotyls and epicotyls, of cotyledon petioles, and indices of cotyledon exposure to the aboveground environment changed during evolution under cultivation. However, those changes occurred in diverse directions, depending on the crop species. No common seedling phenotypic convergence in response to domestication was thus detected among the group of species studied here. Also, none of the 20 crops evolved in accordance with our initial hypothesis. Our results reject the idea that strong selective filters exerted unconsciously by artificial selection should have resulted in generalised channelling of seedling morphology towards more productive and more herbivore risky phenotypes. This result opens up unexplored opportunities for directional breeding of seedling traits.
Functional characterization of terpene synthases and chemotypic variation in three lavender species of section Stoechas
Authors: Benabdelkader Tarek , Guitton Yann , Pasquier Bernard , Magnard Jean Louis , Jullien Frédéric , Kameli Abdelkrim , Legendre Laurent
Published: June 2014

Lavandula pedunculata (Mill.) Cav. subsp. lusitanica, Lavandula stoechas L. subsp. stoechas and Lavandula viridis l'Hér. are three lavender taxa that belong to the botanical section Stoechas and are widely used as aromatherapy, culinary herb or folk medicine in many Mediterranean regions. The analysis of their bioactive volatile constituents revealed the presence of 124 substances, the most abundant being the bicyclic monoterpenes fenchone, camphor and 1,8‐cineole that give these three species their respective chemotypes. Most noteworthy was fenchone which, with its reduced form fenchol, made 48% of the total volatile constituents of L. pedunculata while present at 2.9% in L. stoechas and undetectable in L. viridis. In order to provide a molecular explanation to the differences in volatile compounds of these three species, two monoterpene synthases (monoTPS) and one sesquiterpene synthase (sesquiTPS) were cloned in L. pedunculata and functionally characterized as fenchol synthase (LpFENS), α‐pinene synthase (LpPINS) and germacrene A synthase (LpGEAS). The two other lavender species contained a single orthologous gene for each of these three classes of TPS with similar enzyme product specificities. Expression profiles of FENS and PINS genes matched the accumulation profile of the enzyme products unlike GEAS. This study provides one of the rare documented cases of chemotype modification during plant speciation via changes in the level of plant TPS gene expression, and not functionality.
Application of in vitro digestibility methods in aquaculture: constraints and perspectives
Authors: Moyano Francisco J. , Saénz de Rodrigáñez Miguel A. , Díaz Manuel , Tacon Albert G. J.
Published: June 2014

In vitro assays simulating the digestion process have been extensively used in the evaluation of the nutritional quality of foods and feeds for humans and terrestrial animals. Such techniques have been comparatively less used in nutrition of aquacultured species, although in recent years the interest in developing alternatives to the conventional in vivo digestibility assays has increased. Using 65 published papers as a reference, this review summarizes the different approaches and configurations used to date in the simulation of the digestion of food by aquatic animals, as well as the main limitations detected in the different methods and the potential advantages derived from their application. Some recommendations are suggested to develop suitable in vitro assays oriented either to the nutritional evaluation of feed ingredients or to get a more detailed knowledge on the interactions among digestive enzymes and feed components.
Comparison of Cryoprotective Effects of Lycopene and Cysteamine in Different Cryoprotectants on Bull Semen and Fertility Results
Authors: Tuncer PB , Büyükleblebici S , Eken A , Taşdemir U , Durmaz E , Büyükleblebici O , Çoşkun E
Published: June 2014

Contents

The objectives of this study were to compare glycerol and ethylene glycol at different concentrations as cryoprotectants and lycopene or cysteamine (with/without) as antioxidants in Tris extender for bull semen. Twenty‐four ejaculates were obtained from three bulls. Each ejaculate was split into four equal aliquots and diluted using both of the Tris extenders with glycerol (5% or 7%) or ethylene glycol (3% or 5%). After that, each extenders were split into three equal aliquots and added using both of the cysteamine 5 mm or lycopene 500 μg/ml, and control (without additives). The addition of 7% glycerol with cysteamine, 5% ethylene glycol with cysteamine and 3% ethylene glycol with cysteamine groups gave the lowest CASA motility than the other groups. However, 7% glycerol and 7% glycerol with lycopene resulted in a better rate of CASA progressive motility compared with that of other groups. Generally, all the lycopene groups signed better protective effects on acrosome and total morphology than the other groups. Glycerol 7% and 3% ethylene glycol with lycopene groups yielded to slight higher percentages of membrane integrity assessed by HOST than that of the other groups, but 7% glycerol with cysteamine and 3% ethylene glycol with cysteamine showed the worst percentages of membrane integrity. Glycerol 7% and 5% glycerol with lycopene gave rise to a higher value of VAP, VSL and VCL compared with that of the other groups. On the contrary, adding to 5% glycerol with cysteamine showed negative effect for VAP, VSL, VCL and ALH values. All cryoprotectant groups with lycopene decreased chromatin damage than the other groups. Ethylene glycol 3% led to lower non‐return rates of inseminated cows. However, this result was not considered to be statistically important.
Testing theMarshall–Lerner Condition inKenya
Authors: Caporale Guglielmo Maria , Gil‐Alana Luis Alberiko , Mudida Robert
Published: June 2014

In this paper we examine theMarshall–Lerner (ML) condition for the Kenyan economy. In particular, we use quarterly data on the log of real exchange rates, export/import ratio and relative (US) income for the time period 1996q1‐2011q4, and employ techniques based on the concept of long memory or long‐range dependence. Specifically, we use fractional integration and cointegration methods, which are more general than standard approaches based exclusively on integer degrees of differentiation. The results indicate that there exists a well‐defined, cointegrating relationship linking the balance of payments to the real exchange rate and relative income, and that theMLcondition is satisfied in the long run, although the convergence process is relatively slow. They also imply that a moderate depreciation of the Kenyan shilling may have a stabilising influence on the balance of trade through the current account without the need for high interest rates.