bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature‐ and latitude‐specific individual growth rates shape the vulnerability of damselfly larvae to a widespread pesticide
Authors: Dinh Van Khuong , Janssens Lizanne , Debecker Sara , Stoks Robby 
Published: April 2014

Summary

Freshwater ecosystems are especially vulnerable to climate change and pollution. One key challenge for aquatic toxicology is to determine and manage the combined effects of temperature increase and contaminants across species' ranges.

We tested how thermal adaptation and life‐history evolution along a natural temperature gradient influence the vulnerability of an aquatic insect to a pesticide under global warming. We applied a space‐for‐time substitution approach to study the effect of warming on the vulnerability of Ischnura elegans damselfly larvae to the pesticide chlorpyrifos in a common garden warming experiment (20 and 24 °C) with replicated populations from three latitudes spanning >1500 km in Europe.

Chlorpyrifos was more toxic to damselfly larvae at the higher temperature: mortality only occurred at 24 °C and the reductions in growth rate were stronger at 24 °C. This could partly be explained by parallel reductions in food intake but not by the activities of two widespread enzymatic biomarkers, glutathione S‐transferase (GST) and acetylcholinesterase (AChE).

There was some evidence that the increased toxicity of the high chlorpyrifos concentration at 24 °C was stronger in terms of growth reduction in the faster‐growing larvae from the low‐latitude populations. This is consistent with energy allocation trade‐offs between growth rate and pesticide tolerance, but suggests that local thermal adaptation does not play a role in coping with pesticide stress.

Synthesis and applications. Damselfly larvae from populations in lower latitudes were more vulnerable to a common pesticide at higher temperatures and pesticide concentrations, whereas evidence for the influence of local thermal adaptation on the vulnerability of larvae was weak. These results emphasize the need for spatially explicit bioassessment and conservation tools. Management practices aimed at mitigating pesticide run‐off into aquatic ecosystems are particularly important in agricultural areas at low latitudes.
Detection and monitoring of pink bollworm moths and invasive insects using pheromone traps and encounter rate models
Authors: Byers John A. , Naranjo Steven E. 
Published: April 2014

Summary

The pink bollworm moth Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) is one of the most destructive pests in agriculture. An ongoing eradication program using a combination of sex pheromone monitoring and mating disruption, irradiated sterile moth releases, genetically modified Bt cotton and local insecticide applications have all but exterminated the pink bollworm from the south‐western USA and portions of northern Mexico. However, the continued threat of reinvasion from Mexico reinforces the need to improve pheromone‐based monitoring. Invasions from other parts of the world such as India, where resistance to single‐gene transgenic Bt cotton has evolved, further heightens the need for better monitoring strategies.

The mean flight height and standard deviation (SD) of the vertical flight distribution of pink bollworm males were estimated from catches on transparent sticky cylinder traps baited with synthetic pheromone at several heights above‐ground. An effective attraction radius (EAR) of a standard pheromone lure was estimated from male moth catches on the pheromone‐baited sticky traps and many similar blank traps. The circular EARc was estimated from the spherical EAR and SD.

The EAR of a pheromone lure for pink bollworm was 1·03 m, and the EARc was 2·61 m. The mean flight height of males was 0·82 m, and the vertical flight distribution SD was 0·26 m.

A computer program simulated male moth movement and capture on various numbers of traps of EARc distributed over areas of 1–100 km2. The simulated catch results were comparable to predictions using the EARc with modified encounter rate equations of Royama and Rogers. The encounter rate equations were solved for initial populations of male moths in the regions, and Poisson statistics were used to calculate population confidence limits.

Synthesis and applications. Encounter rate models and Poisson methods can be used to determine levels of pheromone trap densities that are likely to detect and estimate low population levels of resident or invasive pink bollworms and many other pest insect species.
Identifying pathways for managing multiple disturbances to limit plant invasions
Authors: Tanentzap Andrew J. , Lee William G. , Monks Adrian , Ladley Kate , Johnson Peter N. , Rogers Geoffrey M. , Comrie Joy M. , Clarke Dean A. , Hayman Ella 
Published: April 2014

Summary

Plant invasions are predicted to accelerate in a world with increased anthropogenic disturbance. Non‐native species pre‐adapted to these disturbances may especially be poised to invade novel communities. Conservation managers therefore need predictions of how to alter disturbances to maximize the persistence of native biodiversity.

We tested a multivariate hypothesis about the causal mechanisms underlying plant invasions in an ephemeral wetland in South Island, New Zealand, to inform management of this biodiverse but globally imperilled habitat. Our approach details among the first applications in ecology of Bayesian structural equation modelling, demonstrating its potential to inform management by disentangling the relative importance of strongly intercorrelated processes.

We found that invasion by non‐native plants was lowest in sites where the physical disturbance caused by flooding was both intense and frequent. This effect was stronger than the positive response of non‐native species to high soil N supply, which was positively related to flooding.

Sites flooded over a 4‐year period had greater reductions in invasion than those associated with floods in the year prior to plot measurement because non‐native species lacked traits for long‐term persistence beneath water. Grazer exclusion had a small positive effect on invasion, as non‐native species were preferentially selected by the herbivores at our site.

Our results show that only species adapted to the dominant disturbance regimes at a site may become successful invaders. Species native to ephemeral wetlands have specially evolved traits that allow them to persist and dominate in these sites.

Synthesis and applications. Predictions of invasions in a world of multiple disturbances clearly need to consider whether the evolutionary history of non‐native species predisposes them to invade novel communities. Maintaining hydrological and nutrient regimes of ephemeral wetlands will limit the number of introduced species that are pre‐adapted to become invasive.
How much of the world is woody?
Authors: FitzJohn Richard G. , Pennell Matthew W. , Zanne Amy E. , Stevens Peter F. , Tank David C. , Cornwell William K. 
Published: April 2014

Summary

The question posed by the title of this study is a basic one, and it is surprising that the answer is not known. Recently, assembled trait data sets provide an opportunity to address this, but scaling these data sets to the global scale is challenging because of sampling bias. Although we currently know the growth form of tens of thousands of species, these data are not a random sample of global diversity; some clades are exhaustively characterized, while others we know little to nothing about.

Starting with a data base of woodiness for 39 313 species of vascular plants (12% of taxonomically resolved species, 59% of which were woody), we estimated the status of the remaining taxonomically resolved species by randomization. To compare the results of our method to conventional wisdom, we informally surveyed a broad community of biologists. No consensus answer to the question existed, with estimates ranging from 1% to 90% (mean: 31.7%).

After accounting for sampling bias, we estimated the proportion of woodiness among the world's vascular plants to be between 45% and 48%. This was much lower than a simple mean of our data set and much higher than the conventional wisdom.

Synthesis. Alongside an understanding of global taxonomic diversity (i.e. number of species globally), building a functional understanding of global diversity is an important emerging research direction. This approach represents a novel way to account for sampling bias in functional trait data sets and to answer basic questions about functional diversity at a global scale.
Decoupled evolution of foliar freezing resistance, temperature niche and morphological leaf traits inChileanMyrceugenia
Authors: Pérez Fernanda , Hinojosa Luis F. , Ossa Carmen G. , Campano Francisca , Orrego Fabiola 
Published: April 2014

SummaryPhylogenetic conservatism of tolerance to freezing temperatures has been cited to explain the tendency of plant lineages to grow in similar climates. However, there is little information about whether or not freezing resistance is conserved across phylogenies, and whether conservatism of physiological traits could explain conservatism of realized climatic niches. Here, we compared the phylogenetical lability of realized climatic niche, foliar freezing resistance and four morphological leaf traits that are generally considered to be adaptations to frost resistance in the Chilean species ofMyrceugenia, which grows in a wide range of habitats.We estimated the predicted niche occupancy profiles with respect to minimum temperature (minT) of all species. We measured foliar freezing resistance (using chlorophyll fluorescence), leaf size, leaf mass per area (LMA), stomatal and trichome densities of 10 individuals per species. Finally, we estimated phylogenetic signal, and we performed independent contrast analyses among all variables.We found that both foliar freezing resistance and minT were subject to a significant phylogenetic signal, but the former had a stronger signal. We also detected a significant, but weak correlation between them (r = 0.49,Pone tail = 0.04). Morphological traits evolved independent of any phylogenetic effect.Synthesis. Our results show that freezing resistance evolved in association with temperature niche, but with some delay that could result from phylogenetic inertia. Our results also show that morphological leaf traits are more labile than realized climatic niche and frost tolerance and that the formers probably evolved in association with microhabitat preferences.
Both flowering time and distance to conspecific plants affect reproduction in Echinacea angustifolia, a common prairie perennial
Authors: Ison Jennifer L. , Wagenius Stuart 
Published: April 2014

Summary

In small fragmented plant populations, reproductive failure due to pollen limitation is often attributed to spatial isolation of individuals. While flowering time has been shown to affect seed set, its role in pollen limited fragmented populations is less understood.

In this study, we quantified near‐neighbour distances, flowering phenology, and how they interact to affect seed set in individual plants. We followed the daily flowering phenology of over 2400 heads on over 500 Echinacea angustifolia individuals and quantified the resulting seed set during three consecutive flowering seasons. The study was conducted in an experimental plot where we randomized planting locations to eliminate spatial patterns of mate availability which are common in fragmented populations of Echinacea, a self‐incompatible plant.

We found that individual flowering time had a larger and more consistent effect on seed set than did spatial location. Seed set in the earliest flowering plants exceeded seed set in the latest by 46–70% in all three years. The role of spatial isolation, characterized both by individual distance to conspecific plants and by location in the plot, was less consistent and showed a weaker relationship with seed set than did flowering phenology. The most isolated plants set 20–27% less seed than the least isolated plants in 2005–2006 with no difference in 2007.

In one year, we quantified seed set by floret position within a flowering head. We found significant positional effects; however, effects due to flowering time were much greater. These results were more consistent with the pollen limitation hypothesis than the resources limitation hypothesis.

Synthesis. Our results illustrate that flowering time and distance to neighbouring conspecifics can cause reproductive failure in fragmented populations, even in the absence of mate limitation caused by mating incompatibility. These findings suggest that flowering time may be an underappreciated contributor to reproductive failure in small fragmented populations.
Interactions between anaerobic ammonium and sulfur‐oxidizing bacteria in a laboratory scale model system
Authors: Russ Lina , Speth Daan R. , Jetten Mike S. M. , Op den Camp Huub J. M. , Kartal Boran 
Published: April 2014

SummaryFixed nitrogen is released by anaerobic ammonium oxidation (anammox) and/or denitrification from (marine) ecosystems. Nitrite, the terminal electron acceptor of the anammox process, occurs in nature at very low concentrations and is produced via (micro)aerobic oxidation of ammonium or nitrate reduction. The coupling of sulfide‐dependent denitrification to anammox is particularly interesting because besides hydrogen, sulfide is the most important reductant at the chemocline of anoxic marine basins and is abundant within sediments. Although at μM concentrations, sulfide may be toxic and inhibiting anammox activity, a denitrifying microorganism could convert sulfide and nitrate at sufficiently high rates to allow anammox bacteria to stay active despite an influx of sulfide. To test this hypothesis, a laboratory scale model system containing a co‐culture of anammox bacteria and the autotrophic denitrifier Sulfurimonas denitrificans DSM1251 was started. Complementary techniques revealed that the gammaproteobacterial Sedimenticola sp. took over the intended role of Su. denitrificans. A stable coculture of anammox bacteria and Sedimenticola sp. consumed sulfide, nitrate, ammonium and CO2. Anammox bacteria contributed 65–75% to the nitrogen loss from the reactor. The cooperation between anammox and sulfide‐dependent denitrification may play a significant role in environments where sulfur cycling is active and where actual sulfide concentrations stay below μM range.
15N‐ and 2H proteomic stable isotope probing links nitrogen flow to archaeal heterotrophic activity
Authors: Justice Nicholas B. , Li Zhou , Wang Yingfeng , Spaudling Susan E. , Mosier Annika C. , Hettich Robert L. , Pan Chongle , Banfield Jillian F. 
Published: April 2014

SummaryUnderstanding how individual species contribute to nutrient transformations in a microbial community is critical to prediction of overall ecosystem function. We conducted microcosm experiments in which floating acid mine drainage (AMD) microbial biofilms were submerged – recapitulating the final stage in a natural biofilm life cycle. Biofilms were amended with either 15NH4+ or deuterium oxide (2H2O) and proteomic stable isotope probing (SIP) was used to track the extent to which different members of the community used these molecules in protein synthesis across anaerobic iron‐reducing, aerobic iron‐reducing and aerobic iron‐oxidizing environments. Sulfobacillus spp. synthesized 15N‐enriched protein almost exclusively under iron‐reducing conditions whereas the Leptospirillum spp. synthesized 15N‐enriched protein in all conditions. There were relatively few 15N‐enriched archaeal proteins, and all showed low atom% enrichment, consistent with Archaea synthesizing protein using the predominantly 14N biomass derived from recycled biomolecules. In parallel experiments using 2H2O, extensive archaeal protein synthesis was detected in all conditions. In contrast, the bacterial species showed little protein synthesis using 2H2O. The nearly exclusive ability of Archaea to synthesize proteins using 2H2O may be due to archaeal heterotrophy, whereby Archaea offset deleterious effects of 2H by accessing 1H generated by respiration of organic compounds.
Antihypertensive and antithrombotic activities of a commercial fermented milk product made with Lactobacillus casei Shirota and Streptococcus thermophilus
Authors: Domínguez‐González Karina N , Cruz‐Guerrero Alma , González‐Márquez Humberto , Gómez‐Ruiz Lorena , García‐Garibay Mariano , Jiménez‐Guzmán Judith , Rodríguez‐Serrano Gabriela 
Published: April 2014

Peptides which inhibit the human angiotensin‐converting enzyme (ACE) may be released during milk fermentation, and the micro‐organisms or fermentation conditions influence the specific peptides produced. The aim of this study was to evaluate the ACE inhibitory and antithrombotic activities of a fermented milk product commercially available in Mexico. Viable cell numbers, protein hydrolysis and the pH remained constant during refrigerated storage. The IC50 of ACE inhibitory activity was 31.38 mg/mL. Eight peptide fractions exhibited ACE inhibitory activity and six showed antithrombotic activity. Two fractions showed both. This is the first time that both activities have been reported in a commercial probiotic product.
Gram‐negative bacteria can also form pellicles
Authors: Armitano Joshua , Méjean Vincent , Jourlin‐Castelli Cécile 
Published: April 2014

SummaryThere is a growing interest in the bacterial pellicle, a biofilm floating at the air–liquid interface. Pellicles have been well studied in the Gram‐positive bacterium Bacillus subtilis, but far less in Gram‐negative bacteria, where pellicle studies have mostly focused on matrix components rather than on the regulatory cascades involved. Several Gram‐negative bacteria, including pathogenic bacteria, have been shown to be able to form a pellicle under static conditions. Here, we summarize the growing body of knowledge about pellicle formation in Gram‐negative bacteria, especially about the components of the pellicle matrix. We also propose that the pellicle is a specific biofilm, and that its formation involves particular processes. Since this lifestyle concerns a growing number of bacteria, its properties undoubtedly deserve further investigation.
Fluorescence in situ hybridization probes targeting members of the phylum Candidatus Saccharibacteria falsely target Eikelboom type 1851 filaments and other Chloroflexi members
Authors: Nittami Tadashi , Speirs Lachlan B. M. , Fukuda Junji , Watanabe Masatoshi , Seviour Robert J. 
Published: April 2014

SummaryThe FISH probe TM7‐305 is thought to target the filamentous Eikelboom morphotype 0041 as a member of the Candidatus ‘Saccharibacteria’ (formerly TM7) phylum. However, with activated sludge samples in both Japan and Australia, this probe hybridized consistently with filamentous bacteria fitting the description of the morphotype 1851, which also responded positively to the CHL1851 FISH probe designed to target Chloroflexi members of this morphotype. 16S rRNA clone libraries from samples containing type 1851 TM7‐305‐positive filaments yielded Chloroflexi clones with high sequence similarity to Kouleothrix aurantiaca. These contained a variant TM7‐305 probe target site possessing weakly destabilizing mismatches insufficient to prevent probe hybridization. Furthermore, the TM7‐905 FISH probe, designed to target members of the entire Candidatus ‘Saccharibacteria’ phylum, also hybridized with the filament morphotypes 0041/0675, which responded also to the phylum level Chloroflexi probes. Many Chloroflexi sequences have only a single base mismatch to the TM7‐905 probe target sequence. When competitor probes for both the TM7‐305 and TM7‐905 Chloroflexi non‐target sites were applied, no fluorescent signal was seen in any of the filamentous organisms also hybridizing with the aforementioned Chloroflexi probes. These data indicate that these competitor probes must be included in hybridizations when both the TM7‐905 and TM7‐305 FISH probes are applied, to minimize potential false positive FISH results.
Bioinformatics analysis and expression study of fumarate hydratase in lung cancer
Authors: Ming Zongjuan , Jiang Meihua , Li Wei , Fan Na , Deng Wenjing , Zhong Yujie , Zhang Yuping , Zhang Qiuhong , Yang Shuanying 
Published: April 2014

AbstractBackgroundAs its etiology and pathogenesis is obscure, illustrating the molecular mechanism of lung cancer has become a serious and urgent task. Studies have shown that fumarate hydratase (FH) is a tumor suppressor related to tumorigenesis, development, and invasion. Our aim was to analyze the biological information of FH, and detect the messenger ribonucleic acid (mRNA) and protein expression of FH in lung cancer cells to explore its role in tumorigenesis and in the development of lung cancer.MethodWe analyzed the biological characteristics of FH, then utilized reverse transcription‐polymerase chain reaction (RT‐PCR) to study FH mRNA expression in A549 and 16 human bronchial epithelial (HBE) cell lines. The protein expression of FH was detected in 57 cases of human lung cancer tissues and 19 cases of normal lung tissues by immunohistochemistry.Results1. Bioinformatic analysis: FH mainly exist in the mitochondria; the common structural elements of FH are mainly α‐helix, random coil, β‐turn, and extended strand; there are five possible transmembrane domains in the entire polypeptide chain; FH is a hydrophilic and soluble protein. 2. RT‐PCR result: FH mRNA expression was downregulated in A549 cells compared with 16HBE cells. 3. Immunohistochemistry: FH protein expression was significantly lower in lung cancer cells than in normal lung tissues (P < 0.05), but was not correlated with the patients' age, gender, tumor size, pathological type, or lymph node, distant, or tumor node metastasis stage.ConclusionFH was under‐expressed in lung cancer, suggesting that it may be an indicator of tumorigenesis and could be a potential target for therapies against lung cancer in the future.
Clinical characteristics of the mixed form of neuroendocrine tumor in the lung: A retrospective study in 2501 lung cancer cases
Authors: Li Dong‐Hai , Wang Chun , Chen Hui‐Jiao , Huang Hui , Ding Zhen‐Yu 
Published: April 2014

AbstractBackgroundA neuroendocrine tumor (NET) is a special kind of epithelial tumor with predominant neuroendocrine differentiation, which arises throughout the body, including the lung. A subpopulation of lung cancer patients suffer from the mixed (combined) form of NET with components of non‐neuroendocrine carcinoma. However, the clinical characteristics of the mixed form of NET are not well established.MethodsWe analyzed 2501 consecutive cases of primary lung cancer from 2009 to 2011. The diagnosis, histology, therapy, and outcome were collected.ResultsA total of 22 patients were enrolled. The occurrence rate of lung cancer was 0.9%. Neither gender (1.2% and 0.3% for male and female, respectively, P = 0.35) nor age (0.6% and 1.3% for patients aged ≤60 and >60, respectively, P = 0.13) was associated with the onset of this disease; however it has become more frequent in recent years (0.6% and 1.6% at the time ≤ and >2010 respectively, P = 0.03). This cohort of 22 patients had a median survival of 60.0 months (95% confidence interval: 14.3–105.6 months). Patients with metastatic disease (60 months and not reached [NR], P = 0.18) or a small‐cell lung cancer component tended to have a shorter survival (35 months and NR, P = 0.16). Patients who underwent surgery had a significantly longer survival period (NR and 17.0 months, P = 0.001).ConclusionsA mixed form of NET in the lung is a rare disease. While stage and histology might influence prognosis, surgery is the critical factor for long‐term survival.