bluuebunny/crossref_metadata_2025 huggingface dataset:
BS-Seeker2: a versatile aligning pipeline for bisulfite sequencing data
Authors: Guo Weilong , Fiziev Petko , Yan Weihong , Cokus Shawn , Sun Xueguang , Zhang Michael Q , Chen Pao-Yang , Pellegrini Matteo
Published: November 2013

Background

DNA methylation is an important epigenetic modification involved in many biological processes. Bisulfite treatment coupled with high-throughput sequencing provides an effective approach for studying genome-wide DNA methylation at base resolution. Libraries such as whole genome bisulfite sequencing (WGBS) and reduced represented bisulfite sequencing (RRBS) are widely used for generating DNA methylomes, demanding efficient and versatile tools for aligning bisulfite sequencing data.

Results

We have developed BS-Seeker2, an updated version of BS Seeker, as a full pipeline for mapping bisulfite sequencing data and generating DNA methylomes. BS-Seeker2 improves mappability over existing aligners by using local alignment. It can also map reads from RRBS library by building special indexes with improved efficiency and accuracy. Moreover, BS-Seeker2 provides additional function for filtering out reads with incomplete bisulfite conversion, which is useful in minimizing the overestimation of DNA methylation levels. We also defined CGmap and ATCGmap file formats for full representations of DNA methylomes, as part of the outputs of BS-Seeker2 pipeline together with BAM and WIG files.

Conclusions

Our evaluations on the performance show that BS-Seeker2 works efficiently and accurately for both WGBS data and RRBS data. BS-Seeker2 is freely available at http://pellegrini.mcdb.ucla.edu/BS_Seeker2/ and the Galaxy server.
A comprehensive meta QTL analysis for fiber quality, yield, yield related and morphological traits, drought tolerance, and disease resistance in tetraploid cotton
Authors: Said Joseph I , Lin Zhongxu , Zhang Xianlong , Song Mingzhou , Zhang Jinfa
Published: November 2013

Background

The study of quantitative trait loci (QTL) in cotton (Gossypium spp.) is focused on traits of agricultural significance. Previous studies have identified a plethora of QTL attributed to fiber quality, disease and pest resistance, branch number, seed quality and yield and yield related traits, drought tolerance, and morphological traits. However, results among these studies differed due to the use of different genetic populations, markers and marker densities, and testing environments. Since two previous meta-QTL analyses were performed on fiber traits, a number of papers on QTL mapping of fiber quality, yield traits, morphological traits, and disease resistance have been published. To obtain a better insight into the genome-wide distribution of QTL and to identify consistent QTL for marker assisted breeding in cotton, an updated comparative QTL analysis is needed.

Results

In this study, a total of 1,223 QTL from 42 different QTL studies in Gossypium were surveyed and mapped using Biomercator V3 based on the Gossypium consensus map from the Cotton Marker Database. A meta-analysis was first performed using manual inference and confirmed by Biomercator V3 to identify possible QTL clusters and hotspots. QTL clusters are composed of QTL of various traits which are concentrated in a specific region on a chromosome, whereas hotspots are composed of only one trait type. QTL were not evenly distributed along the cotton genome and were concentrated in specific regions on each chromosome. QTL hotspots for fiber quality traits were found in the same regions as the clusters, indicating that clusters may also form hotspots.

Conclusions

Putative QTL clusters were identified via meta-analysis and will be useful for breeding programs and future studies involving Gossypium QTL. The presence of QTL clusters and hotspots indicates consensus regions across cultivated tetraploid Gossypium species, environments, and populations which contain large numbers of QTL, and in some cases multiple QTL associated with the same trait termed a hotspot. This study combines two previous meta-analysis studies and adds all other currently available QTL studies, making it the most comprehensive meta-analysis study in cotton to date.
Comfort, safety and quality of upper gastrointestinal endoscopy after 2 hours fasting: a randomized controlled trial
Authors: Koeppe Angélica Terezinha , Lubini Marcio , Bonadeo Nilton Maiolini , Moraes Iran , Fornari Fernando
Published: November 2013

Background

Upper gastrointestinal endoscopy has been performed after fasting 8 or more hours, which can be harmful to the patients. We assessed comfort, safety and quality of endoscopy under moderate sedation after 2 hours fasting for clear liquids.

Methods

In this clinical trial, patients referred for elective endoscopy were randomly assigned to a fasting period of 8 hours (F8) or a shorter fasting (F2), in which 200 ml of clear liquids were ingested 2 hours before the procedure. Endoscopists blinded to patients fasting status carried out the endoscopies. Comfort was rated by the patients, whereas safety and quality were determined by the endoscopists.

Results

Ninety-eight patients were studied (aging 48.5 ± 16.5 years, 60% women): 50 patients (51%) in F2 and 48 in F8. Comfort was higher in F2 than F8 in regard to anxiety (8% vs. 25%; P = 0.029), general discomfort (18% vs. 42%; P = 0.010), hunger (44% vs. 67%; P = 0.024), and weakness (22% vs. 42%; P = 0.034). Regurgitation of gastric contents into the esophagus after endoscopic intubation did not differ between F2 and F8 (26% vs. 19%; P = 0.471). There was no case of pulmonary aspiration. Gastric mucosal visibility was normal in most patients either in F2 or F8 (96% vs. 98%; P = 0.999).

Conclusions

Elective upper GI endoscopy after 2 hours fasting for clear liquids was more comfortable and equally safe compared to conventional fasting. This preparation might be cautiously applied for patients in regular clinical conditions referred for elective endoscopy.

Trial registration

SAMMPRIS ClinicalTrial.gov number, NCT01492296
Targeted exome sequencing for mitochondrial disorders reveals high genetic heterogeneity
Authors: DaRe Jeana T , Vasta Valeria , Penn John , Tran Nguyen-Thao B , Hahn Si Houn
Published: November 2013

Background

Mitochondrial disorders are difficult to diagnose due to extreme genetic and phenotypic heterogeneities.

Methods

We explored the utility of targeted next-generation sequencing for the diagnosis of mitochondrial disorders in 148 patients submitted for clinical testing. A panel of 447 nuclear genes encoding mitochondrial respiratory chain complexes, and other genes inducing secondary mitochondrial dysfunction or that cause diseases which mimic mitochondrial disorders were tested.

Results

We identified variants considered to be possibly disease-causing based on family segregation data and/or variants already known to cause disease in twelve genes in thirteen patients. Rare or novel variants of unknown significance were identified in 45 additional genes for various metabolic, genetic or neurogenetic disorders.

Conclusions

Primary mitochondrial defects were confirmed only in four patients indicating that majority of patients with suspected mitochondrial disorders are presumably not the result of direct impairment of energy production. Our results support that clinical and routine laboratory ascertainment for mitochondrial disorders are challenging due to significant overlapping non-specific clinical symptoms and lack of specific biomarkers. While next-generation sequencing shows promise for diagnosing suspected mitochondrial disorders, the challenges remain as the underlying genetic heterogeneity may be greater than suspected and it is further confounded by the similarity of symptoms with other conditions as we report here.
Wnt signaling in triple negative breast cancer is associated with metastasis
Authors: Dey Nandini , Barwick Benjamin G , Moreno Carlos S , Ordanic-Kodani Maja , Chen Zhengjia , Oprea-Ilies Gabriella , Tang Weining , Catzavelos Charles , Kerstann Kimberly F , Sledge George W , Abramovitz Mark , Bouzyk Mark , De Pradip , Leyland-Jones Brian R
Published: November 2013

Background

Triple Negative subset of (TN) Breast Cancers (BC), a close associate of the basal-like subtype (with limited discordance) is an aggressive form of the disease which convey unpredictable, and poor prognosis due to limited treatment options and lack of proven effective targeted therapies.

Methods

We conducted an expression study of 240 formalin-fixed, paraffin-embedded (FFPE) primary biopsies from two cohorts, including 130 TN tumors, to identify molecular mechanisms of TN disease.

Results

The annotation of differentially expressed genes in TN tumors contained an overrepresentation of canonical Wnt signaling components in our cohort and others. These observations were supported by upregulation of experimentally induced oncogenic Wnt/β-catenin genes in TN tumors, recapitulated using targets induced by Wnt3A. A functional blockade of Wnt/β-catenin pathway by either a pharmacological Wnt-antagonist, WntC59, sulidac sulfide, or β-catenin (functional read out of Wnt/β-catenin pathway) SiRNA mediated genetic manipulation demonstrated that a functional perturbation of the pathway is causal to the metastasis- associated phenotypes including fibronectin-directed migration, F-actin organization, and invasion in TNBC cells. A classifier, trained on microarray data from β-catenin transfected mammary cells, identified a disproportionate number of TNBC breast tumors as compared to other breast cancer subtypes in a meta-analysis of 11 studies and 1,878 breast cancer patients, including the two cohorts published here. Patients identified by the Wnt/β-catenin classifier had a greater risk of lung and brain, but not bone metastases.

Conclusion

These data implicate transcriptional Wnt signaling as a hallmark of TNBC disease associated with specific metastatic pathways.
A feasibility study of expert patient and community mental health team led bipolar psychoeducation groups: implementing an evidence based practice
Authors: Coulthard Katharine , Patel Dipty , Brizzolara Clare , Morriss Richard , Watson Stuart
Published: November 2013

Background

Group psychoeducation is a cost effective intervention which reduces relapse and improves functioning in bipolar disorder but is rarely implemented. The aim of this study was to identify the acceptability and feasibility of a group psychoeducation programme delivered by community mental health teams (CMHTs) and peer specialist (PS) facilitators. Organisational learning was used to identify and address systematically barriers and enablers, at organisational, health professional and patient levels, to its implementation into a routine service.

Methods

A systematic examination of barriers and enablers to a three day training process informed the delivery of a first treatment group and a similar process informed the delivery of the second treatment group. Triangulation of research methods improved its internal validity: direct observation of training, self-rated surveys of participant experiences, group discussion, and thematically analysed individual participant and facilitator interviews were employed.

Results

Barriers and enablers were identified at organisational, educational, treatment content, facilitator and patient levels. All barriers under the control of the research team were addressed with subsequent improvements in patient knowledge about the condition and about local service. In addition, self-management, agency and altruism were enhanced. Barriers that could not be addressed required senior clinical and education leadership outside the research team’s control. PS and professional facilitators were successfully trained and worked together to deliver groups which were generally reported as being beneficial.

Conclusion

Psychoeducation groups involving CMHT and PS facilitators is acceptable and feasible but their sustainment requires senior leadership within and outside the organisation that control finance and education services.
Inactivated autograft–prosthesis composite have a role for grade III giant cell tumor of bone around the knee
Authors: Xu SongFeng , Yu XiuChun , Xu Ming , Fu ZhiHou
Published: November 2013

Background

Giant cell tumors (GCT) around the knee are common and pose a special problem of reconstruction after tumor excision, especially for grade III GCT. We questioned whether en bloc resection and reconstruction with alcohol inactivated autograft-prosthesis composite would provide (1) local control and long-term survival and (2) useful limb function in patients who had grade III GCT around the knee.

Methods

We retrospectively reviewed eight patients (5 males and 3 females) treated with this procedure with mean age of 31 years (range 20 to 43 years) from Jan 2007 to Oct 2008. 5 lesions were located in distal femur and 3 in proximal tibia. 4 patients were with primary tumor and the other 4 with recurrence. 2 patients showed pathological fracture.

Results

Mean Follow-up is 54 months ranging from 38 to 47 months. No recurrence, metastasis, prosthesis loosening were found. The mean healing time between autograft and host bone was 5.5 months. The mean MSTS score was 26.3 (88%) ranging from 25 to 29. The mean ISOLS composite graft score was 32.8 (88.5%) ranging from 28 to 35. Creeping substitution is possibly the main way in bony junction. The healing time in femoral lesion is faster than that in tibial lesion.

Conclusions

The technique of alcohol inactivated autograft-prosthesis composite could be able to achieve satisfactory oncological and functional outcomes in Grade III GCT.
Evaluation of ranges of motion of a new constrained acetabular prosthesis for canine total hip replacement
Authors: Wu Ching-Ho , Lin Cheng-Chung , Lu Tung-Wu , Hou Sheng-Mao , Hu Chih-Chung , Yeh Lih-Seng
Published: November 2013

Background

Total hip replacement (THR) is considered to be the most effective treatment option for advanced osteoarthritis of the hip in large breed dogs. However, a proportion of post-THR patients suffer prosthesis dislocation for various reasons, which may be addressed by a constrained acetabular prosthesis design. The study proposed a new THR with constrained acetabular component that aimed to decrease the incidence of postoperative dislocation while maintaining the necessary range of motion (ROM); and, through computer-simulated implantations, evaluated the ROM of the THR with and without malpositioning of the acetabular component.

Methods

A new THR with a constrained acetabular component that had an inward eccentric lining and a 60° cut-out on the dorsal side was designed, and its computer-aided design models were implanted into the pelvic and femoral models reconstructed from the computed tomography data of six healthy Labrador Retriever dogs. The allowable and functional ROM of the implanted THR were determined via computer simulations. The contact patterns between the bone or the prosthetic components at extreme positions of the THR were analyzed. Influence of malpositioning of the acetabular component on the ROM was assessed.

Results

The means (SD) of the functional ranges for flexion, extension, adduction, abduction, internal rotation and external rotation were 51.8° (6.6°), 163.3° (7.3°), 33.5° (5.7°), 74.0° (3.7°), 41.5° (8.3°) and 65.2° (9.9°), respectively. Malpositioning of the acetabular component by 20° in one direction was found to reduce ROM in other directions (reducing lateral opening: flexion: 12°, adduction: 20°, internal/external rotations: < 20°; increasing lateral opening: extension and abduction: < 16°; reducing retroversion: extension: < 20°, abduction: 15°, external rotation: < 20°; increasing retroversion: flexion: < 20°, abduction, adduction and internal rotation: 20°).

Conclusions

From the computer-aided surgical simulations, the new THR was found to have sufficient functional ranges for flexion, extension, abduction, adduction and external rotation for Labrador Retrievers. Analysis of the malpositioning of the acetabular component suggests that accurate placement of the acetabular component is critical for achieving desirable ROM for daily activities.
Massive hemoptysis controlled with transection of a pulmonary vein and bronchus-a case report
Authors: Ho Hui-Ju , Cheng Ching-Yuan , Wang Bing-Yen
Published: November 2013

Massive hemoptysis caused by bronchiectasis in which bronchial artery embolization does not control the bleeding is not rare. Traditional surgical intervention is anatomical lung resection. We present a case of a patient with bronchiectasis and massive hemoptysis in which the bleeding was controlled with transection of a pulmonary vein and bronchus with preservation of the pulmonary artery.
Characterization of PfTrxR inhibitors using antimalarial assays and in silicotechniques
Authors: Munigunti Ranjith , Gathiaka Symon , Acevedo Orlando , Sahu Rajnish , Tekwani Babu , Calderón Angela I
Published: November 2013

Background

The compounds 1,4-napthoquinone (1,4-NQ), bis-(2,4-dinitrophenyl)sulfide (2,4-DNPS), 4-nitrobenzothiadiazole (4-NBT), 3-dimethylaminopropiophenone (3-DAP) and menadione (MD) were tested for antimalarial activity against both chloroquine (CQ)-sensitive (D6) and chloroquine (CQ)-resistant (W2) strains ofPlasmodium falciparumthrough anin vitroassay and also for analysis of non-covalent interactions withP. falciparumthioredoxin reductase (PfTrxR) throughin silicodocking studies.

Results

The inhibitors ofPfTrxR namely, 1,4-NQ, 4-NBT and MD displayed significant antimalarial activity with IC50values of < 20 μM and toxicity against 3T3 cell line. 2,4-DNPS was only moderately active.In silicodocking analysis of these compounds withPfTrxR revealed that 2,4-DNPS, 4-NBT and MD interact non-covalently with the intersubunit region of the enzyme.

Conclusions

In this study, tools for the identification ofPfTrxR inhibitors using phenotyphic screening and docking studies have been validated for their potential use for antimalarial drug discovery project.
The C-terminal extension of Lsm4 interacts directly with the 3′ end of the histone mRNP and is required for efficient histone mRNA degradation
Authors: Lyons Shawn M. , Ricciardi Adele S. , Guo Andrew Y. , Kambach Christian , Marzluff William F.
Published: November 2013

Metazoan replication-dependent histone mRNAs are the only known eukaryotic mRNAs that lack a poly(A) tail, ending instead in a conserved stem–loop sequence, which is bound to the stem–loop binding protein (SLBP) on the histone mRNP. Histone mRNAs are rapidly degraded when DNA synthesis is inhibited in S phase in mammalian cells. Rapid degradation of histone mRNAs is initiated by oligouridylation of the 3′ end of histone mRNAs and requires the cytoplasmic Lsm1-7 complex, which can bind to the oligo(U) tail. An exonuclease, 3′hExo, forms a ternary complex with SLBP and the stem–loop and is required for the initiation of histone mRNA degradation. The Lsm1-7 complex is also involved in degradation of polyadenylated mRNAs. It binds to the oligo(A) tail remaining after deadenylation, inhibiting translation and recruiting the enzymes required for decapping. Whether the Lsm1-7 complex interacts directly with other components of the mRNP is not known. We report here that the C-terminal extension of Lsm4 interacts directly with the histone mRNP, contacting both SLBP and 3′hExo. Mutants in the C-terminal tail of Lsm4 that prevent SLBP and 3′hExo binding reduce the rate of histone mRNA degradation when DNA synthesis is inhibited.
Bringing English into the 21st century: A view from India
Authors: Bhaya Nair Rukmini
Published: November 2013

English in India has had an extended and elite colonial history. It was the dominant language of governance in the 19th and 20th centuries till India became independent and a new set of language policies came into being. This paper traces the narrative of English on the Indian subcontinent from its genesis as a foreign and imperial tongue to its acceptance and ‘democratization’ as one amongst the many languages of India. It is emphasized that English in India has always existed in a vibrant multilingual environment and that the emergence of Indian English as a ‘world’ variety owes much to this fact. A detailed analysis of the lexicon, grammar and pragmatics of the English spoken today in urban India especially by India’s youth who comprise over 65% of India’s population is undertaken in the paper with a view to demonstrating that radical and striking shifts in attitudes toward English in India have occurred over the last few decades of economic liberalization and technological growth. Yet, the timeline created in this paper also shows that many of the paradoxes and dilemmas that attended English from its inception in India have not quite been banished. Rather, they have taken on new, acutely self-reflexive and challenging forms that will require a radical reassessment in the 21st century.
Ants Visiting the Post-Floral Secretions of Pericarpial Nectaries in Palicourea rigida (Rubiaceae) Provide Protection Against Leaf Herbivores But Not Against Seed Parasites
Authors: Del-Claro Kleber , Guillermo-Ferreira Rhainer , Zardini Helena , Almeida Elizângela Machado , Torezan-Silingardi Helena Maura
Published: November 2013

Pericarpial nectaries (PNs) have frequently been treated in the literature as extrafloral nectaries (EFNs). This treatment is partly justified by their morphological and functional similarities in attracting bodyguard ants to protect the plant against herbivores. Palicourea rigida is a common Neotropical savanna treelet with tubular yellow flowers that are pollinated by hummingbirds. After pollination, the corolla falls, but the sepal ring remains and keeps the nectaries active over the ovarium throughout fruit development stages. Using a standard ant-exclusion experiment, we tested whether these PNs attract ants to protect the developing fruits against seed parasites and the leaves against chewing herbivores. We analyzed the differences between the initial and final leaf area. Before full fruits maturity, they were collected and taken to the laboratory for weighing and to observe wasp emergence. The number of wasps per fruit and per plant was recorded. The results showed that after pollination, the floral nectaries of P. rigida act as EFNs, attracting visiting ants. Ant-tended plants lost significantly less leaf area and had heavier fruits than untended plants. However, the ants did not protect the fruits against seed-parasitic wasps. In P. rigida, the post-floral secretions of PNs play the same role as EFNs, and the ant-plant mutualism is context-dependent based on the type of herbivore and the plant tissue consumed.
Ant Fauna on Cecropia pachystachya Trécul (Urticaceae) Trees in an Atlantic Forest Area, Southeastern Brazil
Authors: Reis Paula CJ , DaRocha Wesley D , Falcão Luiz AD , Guerra Tadeu J , Neves Frederico S
Published: November 2013

Cecropia are pioneer successional trees frequently associated with ants. Generally a single dominant colony of Azteca ant inhabits each mature Cecropia tree, but other ant species may be found living or foraging on the same tree. In this study, we assessed the diversity of ant species on Cecropia pachystachya trees in two sites in the Brazilian Atlantic Forest: a dust-free roadside and a dusty roadside. We also investigated the influence of tree architecture on ant species richness. We found a total of 24 ant species distributed in 11 genera and five subfamilies on C. pachystachya trees; 18 in the dust-free roadside and 14 in the dusty roadside. We found up to five ant species on a single tree, but only Azteca alfari was frequently encountered. Ant species richness per tree did not differ significantly between sites and was related to tree architectural traits. On the other hand, ant species composition on trees differed significantly between sites. Our study indicates that heavy dust deposition on Cecropia trees may affect associated ant communities, not by changing ant species richness, but by causing different species to live and forage on trees under different dust exposure.
The Importance of Poneromorph Ants for Seed Dispersal in Altered Environments
Authors: Almeida Fabio Souto , Mayhe-Nunes Antonio José , Queiroz Jarbas M
Published: November 2013

Changes in species composition and an increase in the probability of local or regional extinctions alone are considered alarming consequences of human disturbances. However, these changes bring other damages that have passed unnoticed by scientists, such as the loss of ecological interactions. In the present study, we assessed fragments of secondary forest and pastures focusing on two aspects of the seed dispersal process: removal rate and dispersal distance. We collected data in forest fragments named Forest 1 (6 ha), Forest 2 (36 ha), and Forest 3 (780 ha), and in a pasture in the municipality of Vassouras, Rio de Janeiro, southeastern Brazil. In each site, we established 40 observation stations containing six seeds of Carica papaya L. (papaya) and monitored seed removal for 2 h at each station. Seventeen ant species removed a total of 316 seeds (32.92% of the seeds). The species that removed the highest number of seeds was Pachycondyla striata Fr. Smith, followed by Odontomachus chelifer (Latreille). The seed removal rate was significantly higher (P < 0.05, Tukey test) in the forest fragment where larger species were more frequent. The average removal distance was significantly longer in two out of three forest fragments (P < 0.05, Tukey test). Larger ants removed more seeds and for longer distances. Hence, seed dispersal was increased by the presence of large-bodied ant species and their high frequency in forest fragments seed dispersal.
The Ecological Effects of Ant-Aphid Mutualism on Plants at a Large Spatial Scale
Authors: Zhang Shuang , Zhang Yuxin , Ma Keming
Published: November 2013

The protective ant-plant interaction has been considered as a model system in studying mutualistic interactions, but we know little about the ecological effects of the mutualism at relatively larger spatial scales. In this study, by excluding an aphid-tending ant species (Lasius fuliginosus) from all host oak trees (Quercus liaotungensis) in 20x20 m plots, we evaluated the effects of ants on herbivory, fruit production and leaf toughness of the host tree. Through a two years study, we found that ants have a significant anti-herbivory effect on the host tree, with no effects on fruit production. At the end of the growing season, leaf toughness for plants without ants increased significantly. This suggests that ants are reliable and effective bodyguards for plants at larger spatial scales. For plants, the possible tradeoff between different defensive strategies at larger scale should be focused in further works.
Protection Mutualisms and the Community: Geographic Variation in an Ant-Plant Symbiosis and the Consequences for Herbivores
Authors: Pringle Elizabeth G. , Gordon Deborah M
Published: November 2013

Protection mutualisms mediate trophic interactions in many systems, but their effects on the surrounding community are rarely studied. Ant-plant symbioses are classic examples of protection mutualisms: myrmecophytic plants provide nesting space and food for symbiotic ants in exchange for ant defense. Ant defense should thus reduce the abundance of herbivores, but studies of ant-plant symbioses usually measure damage to the plant without quantifying the herbivores themselves. In this study, we investigated whether geographic variation in the quality of ant defense in a symbiotic mutualism between Cordia alliodora trees and Azteca ants was associated with the abundance and species richness of plant herbivore communities. In three tropical-dry-forest sites in Middle America, we found that the density of Azteca ants within trees was negatively associated with the levels of leaf herbivory. At sites where ants were effective tree defenders, tree herbivores were less abundant and herbivore assemblages on trees exhibited lower species richness than at a site where ants were poor defenders. In addition, in a site where ants reduced herbivory, herbivore communities were less abundant and diverse in the presence of ants than in their absence, where as in a site where ants did not reduce herbivory, there were no differences in herbivore abundance or richness between trees with or without ants. We conclude that geographic variation in the quality of ant defense drives variation in myrmecophytic-plant herbivore communities. Moreover, ant-plant protection mutualisms should have important but rarely considered effects on herbivore population dynamics and food-plant specialization.
An Herbivore’s Thermal Tolerance is Higher Than That of the Ant Defenders in a Desert Protection Mutualism
Authors: Fitzpatrick Ginny , Davidowitz Goggy , Bronstein Judith L
Published: November 2013

In North American deserts, many species of cactus attract ants to their extrafloral nectaries; the ants actively defend the food source, and hence the plant, against herbivores. In thermally extreme environments, however, networks of positive and negative interactions like these are likely to be sensitive to the thermal limitations of each of the interacting species. We compared the thermal tolerance of a common phytophagous cactus bug, Narnia pallidicornis (Hemiptera: Coreidae), to that of the ants that defend the cactus Ferocactus wislizeni in the Sonoran Desert, USA. We used flow-through respirometry to experimentally determine the thermal limit of the herbivore and compared this to the thermal limits of the ant defenders, determined previously. In the field, we recorded herbivore frequency (proportion of plants with N. pallidicornis) and abundance (the number of N. pallidicornis per plant) in relation to ambient temperature, ant species presence and identity, and fruit production. We show that N. pallidicornis has a higher thermal tolerance than the four most common ant mutualists, and in the laboratory can survive very high temperatures, up to 43°C. Herbivore frequency and abundance in the field were not related to the daily high temperatures observed. Plants that were not defended by ants were occupied by more N. pallidicornis, although they showed no reduction in fruit set. Therefore, herbivory is likely to continue on fishhook barrel cacti even at high temperatures, especially those temperatures beyond the thermal tolerance of the ant defenders. The consequences of increased herbivory, however, remain unclear. Mutualisms are essential for ecosystem functioning; it is important to understand the thermal sensitivity of these interactions, especially in light of expected increases in global temperature regimes.
Coexistence of Aphid Predators in Cacao Plants: Does Ant-aphid Mutualism Play a Role?
Authors: Silva Evandro do Nascimento , Perfecto Ivette
Published: November 2013

Mutualism between ants and hemipterans that produce honeydew has important implications for biological control because hemipterans defended against predators can reach economic injury levels. We tested the hypothesis that ant-aphid mutualism can mediate competition and promote the coexistence of aphid natural enemies. A quadrate in the field measuring 30 x 30 meters (10 plants in 10 rows = 100 plants) was established in a cacao plantation and a whole quadrate survey was carried out in vegetative shoot flushings from the trunk. The number of ants and predators, the identity of ant and natural enemy species and colony occupancy by ants were recorded. Spatial association indexes were used to evaluate the degree of overlap in ant-ant and ant-predator spatial distributions. The ant Crematogaster victima F. Smith was selected for a test on differences in its attack behavior against larvae of the syrphid Ocyptamus antiphates (Walker) and a species of ladybird beetle (Coleoptera: Coccinelidae). Five species of ants were found tending aphids more frequently and their level of spatial association was slightly negative with remarkable mutual exclusion from aphid colonies. Two of them, Cr. victima and Cr. erecta Mayr, were potential defendants of aphids and were selected to study their spatial association with the distribution of natural enemies. It was found that spatial association between ants and aphid predators is slightly positive. The results suggest that the occurrence of attack behavior of Cr. victima against syrphids, but not against coccinellids, can increase coexistence of predators by generating independent spatial distribution.
Pollen Collected and Foraging Activities of Frieseomelitta varia (Lepeletier) (Hymenoptera: Apidae) in an Urban Landscape
Authors: Aleixo Kátia Paula , Faria Letícia Biral de , Garófalo Carlos Alberto , Imperatriz Fonseca Vera Lucia , Silva Cláudia Inês da
Published: November 2013

Cities provide resources for animal species that live within them or inhabit their surroundings. This has motivated an increase in ecological studies of urban areas, including the interactions between plants and pollinators. From March 2010 to February 2011, the flowering plants present in the study area, located at the Universidade de São Paulo, Ribeirão Preto, were sampled to evaluate how floral sources were distributed throughout the year. Concurrently, worker bees with pollen loads were collected from four colonies of Frieseomelitta varia (Lepeletier, 1836) to identify the sources used by bees. Despite an increase in plant species abundance in July, plants were in bloom year-round and consequently, the production and supply of floral resources were continuous. The workers collected resources from 77 plant species, but only three were extensively exploited. Delonix regia (Leguminosae), Poincianella pluviosa (Leguminosae) and Ceiba speciosa (Malvaceae) accounted for 42% of total pollen grains quantified during the year, showing that F. varia intensify pollen collection at few sources at spatiotemporal scale. This study emphasizes the importance of native urban flora to maintain F. varia and other bee species. The list of plants presented in this study can be used in the design and planning of urban areas.
Foraging behavior of Scaptotrigona depilis (Hymenoptera, Apidae, Meliponini) and its relationship with temporal and abiotic factors
Authors: Figueiredo-Mecca Gláucya de , Bego Luci Rolandi , Nascimento Fabio Santos do
Published: November 2013

Stingless bees play an important role in Tropical and Subtropical ecosystems as pollinators of many plants. The aim of this study was to characterize the pattern of flight activity and foraging for pollen by Scaptotrigona depilis workers and their relation with climatic and temporal factors. We observed flight activity from July 2001 to June 2002 and pollen collection by scoring the flow of workers entering and exiting the colonies. We tested whether environmental (temperature, relative humidity, pluviosity and luminosity) and temporal predictors (month and time of day) affected bees’ activities. The study was conducted during one year and the records of observations showed that during the dry season when the length of light is longer, the external activity was more intensive, while during cold months with shorter light period, foraging activity was reduced. Pollen collection showed a peak in February, but in general this activity was regulated by temperature, humidity and daily luminosity.
Food Niche Overlap Among Neotropical Carpenter Bees (Hymenoptera: Apidae: Xylocopini) in an Agricultural System
Authors: Carvalho Danielle Mendes , Aguiar Candida Maria Lima , Santos Gilberto Marcos Mendonça
Published: November 2013

In the present study, we used niche overlap analysis and a network approach to investigate the use of floral resources by carpenter bees (Xylocopa spp.). We assessed the frequency of visit to different plant species and the activity time of carpenter bees in an agricultural system. Six species of carpenter bees were collected visiting flowers. Among the 48 interactions that were theoretically possible in the interaction network, only 19 were recorded (Connectance = 39.58%). The temporal overlap between pairs of species measured by the Shannon index (0 to 0.648) was lower than dietary overlap (0 to 0.967). The network analysis also showed that bees separated their niches more strongly in the temporal dimension (E = 0.72, P < 0.001) than in the dietary dimension (E = 0.55, P < 0.001). The levels of dietary and temporal overlap were strongly correlated with each other, as well as the time of highest frequency of visit coincided with the time of availability of resources by the most important plants (Moringa oleifera, Passiflora edulis, and Solanum palinacanthum). The correlation between dietary and temporal overlap is biologically explained by the presence of plants that structure the system by exerting a strong influence not only on the plant choice by foraging bees, but also on the time of resource collection.
Melittopalynology and Trophic niche analysis of Apis cerana and Apis mellifera in Yunnan Province of Southwest China
Authors: Liu Yu-Jia , Zhao Tian-Rui , Zhang Xue-Wen , Liang Cheng , Zhao Feng-Yun
Published: November 2013

The present study reports results of qualitative melittopalynological analyses of 34 honey samples of Apis cerana and Apis mellifera between 2011 and 2012 in Mengzi (China Yunnan) and the trophic niche analysis of two bee species on pollen food resources. A diverse spectrum of 17 pollen types from 14 families was identified with the Asteraceae and Myrtaceae being most frequent at non-nectar flow and the Lythraceae being most frequent at main nectar flow of pomegranate. The results of trophic niche analysis to Apis cerana and Apis mellifera are these, at non-nectar flow, the Niche breadth are 0.65 and 0.57, respectively; at nectar flow, the values are 0.41 and 0.24, respectively. Trophic niche overlap index, the value of nectar flow(0.68) is greater than non-nectar flow(0.61). Interspecific competition index, the value of nectar flow(0.92) is also greater than non-nectar flow(0.77). These results may promote the development of local beekeeping and help scholars assessing the impact of introduced bees on native bees in China.
Comparing the Structure and Robustness of Passifloraceae - Floral Visitor and True Pollinator Networks in a Lowland Atlantic Forest
Authors: Benevides Cristine Rodrigues , Evans Darren M , Gaglianone Maria Cristina
Published: November 2013

We investigated the plant-pollinator interactions of Passifloraceae occurring in fragments of lowland semi-deciduous Atlantic forest. We described floral biology, pollination syndromes and the pollinators of Passiflora alata, Passiflora kermesina, Passiflora suberosa, Passiflora malacophylla and Mitostemma glaziovii. We examined the robustness of the interaction networks to species loss, a plausible scenario resulting from forest fragmentation. The effects of pollination syndrome (flower size) on network robustness was also examined. Passiflora alata, P. malacophylla and P. suberosa were pollinated by bees of different corporal sizes. P. kermesina and M. glaziovii presented the highest diversity of visitors and were pollinated mainly by hummingbirds and butterflies, respectively. Through the analysis of the networks we differentiate the structures of the flower-visitor network with the ‘true’ plant-pollinator network. The robustness of the flower-visitor network to animal loss was generally high, but it declined when only true pollinators were included in the network. The sequential loss of plants from the flower-visitor network resulted in low robustness: the loss of key plants could have significant cascading effects on the animals feeding on them within the forest fragment. Future studies should consider the interactions between all flowering plants and animals in this habitat in order to guide conservation and management plans for these forest fragments.
Interactions of the Cerrado Palms Butia paraguayensis and Syagrus petraea with Parasitic and Pollinating Insects
Authors: Silberbauer-Gottsberger Ilse , Vanin Sérgio Antonio , Gottsberger Gerhard
Published: November 2013

The two cerrado palms Butia paraguayensis and Syagrus petraea were studied with regard to parasitizing and pollinating insects that visit their reproductive organs. At the study site in Botucatu, São Paulo State, both species occurred together, while at the study site in Indianópolis, Minas Gerais state, only S. petraea was growing. Bees of the subfamily Meliponinae and Halictinae were the main pollinators of B. paraguayensis and several beetles and flies were additional pollinators. The visiting beetles divided up in more exclusive parasites, such as the weevils Tripusus leiospathae and Petalochilus lineolatus, and the Colydiidae Bitoma palmarum, which bored and oviposited the closed spathe and whose larvae fed on the flower buds, as well as species of the weevil Microstrates, which bred in staminate flowers. Differently, the curculionids Anchylorhynchus bicolor, Parisoschoenus sp., Dialomia sp., and species of Mystrops (Nitidulididae) behaved as parasites and pollinators. On the other hand, S. petraea shows more evident adaptations for pollination by beetles. This species has Trigona spinipes as prominent bee pollinator, but otherwise beetles dominated as visitors, being them either parasites, pollinators or both. Although several identical beetle genera occur on both palms, at the species level they are different, as for example Anchylorhynchus camposi on S. petraea. At the two distant study sites of S. petraea in Botucatu and Indianópolis, several species, especially of the parasitic insects, are identical, indicating that parasitism is a stronger bond than pollination in this species which is characterized by a generalist pollination mode.
Centris aenea (Hymenoptera, Apidae): a Ground-nesting Bee with High Pollination Efficiency in Malpighia emarginata DC (Malpighiaceae)
Authors: Oliveira Geane Almeida , Aguiar Cândida Maria Lima , Silva Maise , Gimenes Miriam
Published: November 2013

This study aimed to assess the efficiency of Centris aenea Lepeletier as pollinator of Malpighia emarginata DC. The pollination efficiency was determined according to three criteria: 1) the pollen deposition rate of M. emarginata and other plant species on the thorax ventral region of females, 2) the rate of M. emarginata fruit set after a single visit, and 3) the pollen deposition rate on the stigma after one single visit. 59% of the pollen grains deposited on the ventral region of C. aenea came from flowers of M. emarginata. The fruit set after a single visit by C. aenea (21%) was much higher than that reported previously for Centris tarsata Smith. We argue that pollination efficiency of C. aenea can be related to its body size, since that females of C. aenea can carry larger amounts of pollen grains of M. emarginata than C. tarsata, as well females of C. aenea are able to touch a larger stigma area, resulting in higher fruit sets after a single visit. Our study suggests that only one visit by C. aenea ensures fruit set in M. emarginata.
Implications of the Floral Herbivory on Malpighiacea Plant Fitness: Visual Aspect of the Flower affects the attractiveness to Pollinators
Authors: Ferreira Clébia Aparecida , Torezan-Silingardi Helena Maura
Published: November 2013

The Malpighiaceae family is species-rich and is abundant in Brazil. Malpighiaceae flowers provide oil and pollen to pollinating bees and serve as food for herbivorous insects, which damage the floral structures. Although common in the Cerrado, florivory is still poorly studied. In the present study, we evaluated the effect of florivory in one of the most common genera of Malpighiaceae in the Cerrado (Banisteriopsis) and the impact of florivory on fruiting. The florivory rate was quantified in flowers of B. malifolia belonging to two morphotypes and in flowers of B. variabilis. Additionally, a petal-removal experiment was performed, which simulated the presence of damage in the flowers. The manipulation involved a control group with intact flowers, a group without the standard petal and a group of flowers without common petals. The florivory in the petals (floral area lost) differed between the species, and B. malifolia was the most damaged. The experimental manipulation revealed that intact flowers had a higher fruiting rate compared with the remaining flowers. These results reinforce the concept that florivory renders flowers less attractive to pollinating bees, which negatively affects the fruiting rate and the reproductive success of plants. We suggest that basic studies (such as the present investigation) be extended to further elucidate the effect of interactions between pollinators, plants, and herbivores on the general structure of communities.
Understanding the Complex Structure of a Plant-Floral Visitor Network from Different Perspectives in Coastal Veracruz, Mexico
Authors: Hernández-Yáñez Haydée , Lara-Rodriguez Nubia , Díaz-Castelazo Cecília , Dáttilo Wesley , Rico-Gray Victor
Published: November 2013

Our premise was to understand the basic structure of the flower-flower visitor community at La Mancha in Veracruz, Mexico. We used network analyses to study the structure of this community. In particular, to analyze, (1) if flower color and shape (“as a limited portion of the traditional floral syndromes definition”) were linked to the arrival of certain floral visitors, (2) if visits to flowers were generalist, specific and/or modular; and (3) which plant species, if any, in the core of the network could affect the stability of floral visitors. In order to analyze the organization of the plant-floral visitor community, we prepared network graphics using Pajek, nestedness (as NODF) with Aninhado, and modularity with the SA algorithm. The network obtained was nested suggesting that generalist species (with the most associations) were interacting with specialists (with fewer associations). Furthermore, floral visitors (Hymenoptera, Diptera, Lepidoptera and Trochiilidae) did not exhibit a particular preference for a specific flower color or shape, each pollinator group visited most flowers/colors/shapes considered. The same was similar for all 14 resulting modules. As in other studies, we suggest that pollination leans to generalization rather than to specialization. We suggest that maybe seasonality/food resource could be the factors to analyze as the next step in floral visits which may be the answer to modularity in this seasonal ecosystem.
Social Wasp-Flower Visiting Guild Interactions in Less Structurally Complex Habitats are More Susceptible to Local Extinction
Authors: Clemente Mateus Aparecido , Lange Denise , Dáttilo Wesley , Del-Claro Kleber , Prezoto Fábio
Published: November 2013

Several studies have shown that habitat complexity is an important factor for the dynamic and stability of interacting species. However, it is not known how the habitat complexity may affect the tolerance of wasp-flower interactions to local extinction. Based on this perspective, in this study, we aimed to compare the tolerance of wasp flower visiting guild to local extinction in two different types of vegetation (Riparian Forest and Rocky Grassland). Through observations made during one year, we verified that the structure of the plant-wasp interaction network differed between the two areas, as well as that the robustness to cumulative extinctions had different patterns.  The simulations of cumulative removal of species showed that the network in the Riparian Forest is more robust against the removal of both plants and wasps than that network in Rocky Grassland, since their extinction curves declined more slowly. Therefore, in our study area, we demonstrate that social wasp-plant interactions in areas with lower structural complexity are less tolerant to extinction (i.e. more fragile). We therefore suggest that studies that aim at biodiversity conservation should focus not only in areas where diversity is high, but also in area with lower species richness for the conservation of ecological roles within communities.