bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of root competition and soils on seedling establishment at the ecotone between an arid grassland and succulent shrubland in South Africa
Authors: Shiponeni Ndafuda N. , Carrick Peter J. , Allsopp Nicky , Hoffman M. Timm
Published: April 2013

Questions

What are the effects of root competition from mature plants and soil type on the survival and growth of dominant grass and succulent shrub seedlings at an ecotonal site between arid grassland and succulent shrubland? Do these factors explain the occurrence of separate grass‐dominated and shrub‐dominated communities along the ecotone?

Location

Ecotone between Bushmanland arid grassland and Namaqualand succulent shrublands in the Karoo, South Africa.

Methods

Seedlings of Stipagrostis brevifolia, a perennial C4 grass, and Ruschia robusta, a leaf‐succulent shrub were transplanted into naturally occurring openings within separate Stipagrostis brevifolia and Ruschia robusta communities. The effects of root competition were tested by exposing seedlings to roots of neighbouring adult plants or by excluding the influence of neighbouring roots using metal partitions. The influence of soil on the survival and growth response of seedlings was tested by comparing the response of each species grown in soil of their own community with their response when grown in soil of the other community.

Results

All S. brevifolia seedlings died within the first 3 mo of the experiment, irrespective of competition exclusion or whether they were grown in grassland or shrubland soils. Root competition from mature plants reduced the survival of R. robusta seedlings in the grass community, but not in the shrub community. When seedlings of R. robusta were not exposed to root competition, their survival and biomass in the grass community soil type did not differ from that in the shrub community soil type.

Conclusions

Excluding root competition in the grass community provided favourable conditions for R. robusta seedlings to establish, suggesting that root competition from the grass is more important in maintaining separate grass communities, and that any differences in soil properties are less important in influencing such processes. Our study presents an example where a species' fundamental niche may be differerent from its realized niche, as a result of competitive interactions.
From technology to biology: a malaria genetic toolbox for the functional dissection of essential genes
Authors: Pino Paco
Published: April 2013

Possessing a system that experimentally controls gene expression has been a Holy Grail in molecular malaria research. Several strategies to control gene expression at different levels have been developed; the controlled step can range from transcription initiation to post‐translational modification and/or protein degradation. Strategies successfully developed in model organisms and adapted to the malaria parasite can be classified into four categories aimed at the conditional control of (i) gene deletion, (ii) gene transcription, (iii) mRNA translation, and (iv) protein stability. Here, I intend to describe the various strategies available and compare and contrast their advantages and limitations. In the absence of a unique, ubiquitous solution, it is instrumental to utilize a variety of approaches that can respond to the particular needs of each gene.
Brain size in neonatal and adult Weddell seals: Costs and consequences of having a large brain
Authors: Eisert Regina , Potter Charles W. , Oftedal Olav T.
Published: April 2013

Little is known about the ontogeny of brain size in pinnipeds despite potential functional implications of brain substrate (glucose, oxygen) requirements for diving, fasting, growth, and lactation strategies. We measured brain mass (brM) and cranial capacity (CC) in newborn and adult Weddell seals. Neonatal Weddell seals had brM that represented ~70% of adult brM. Weddell seals have the largest neonatal brain, proportional to adult brain, reported for any mammal to date, which is remarkable considering the relatively small size of Weddell seal pups at birth (6%–7% of maternal body mass) compared to neonates of other highly precocial mammals. Provision of sufficient glucose to maintain the large, well‐developed brain of the neonatal Weddell seal has a nontrivial metabolic cost to both pup and mother. We therefore hypothesize that this phenomenon must have functional significance, such as allowing pups to acquire complex under‐ice navigation skills during the period of maternal attendance.
Prey preferences of sympatric fin (Balaenoptera physalus) and humpback (Megaptera novaeangliae) whales revealed by stable isotope mixing models
Authors: Ryan Conor , Berrow Simon D. , McHugh Brendan , O'Donnell Ciarán , Trueman Clive N. , O'Connor Ian
Published: April 2013

Over‐exploitation of top predators and fish stocks has altered ecosystems towards less productive systems with fewer trophic levels. In the Celtic Sea (CS), discards and bycatch levels have prompted concern about some fisheries, while fin and humpback whales are recovering from centuries of over‐exploitation. A lack of empirical evidence on the preferred diet of some predators such as whales in the CS has hindered the implementation of effective conservation measures using an ecosystem‐based approach to fisheries management. Using a Bayesian framework (SIAR), stable carbon (δ13C) and nitrogen (δ15N) isotope mixing models were used to assign proportionate diet solutions to fin and humpback whales (skin biopsies) and putative prey items: herring (Clupea harengus), sprat (Sprattus sprattus), and krill (Meganyctiphanes norvegica and Nyctiphanes couchii) in the CS. Krill was the single most important prey item in the diet of fin whales, but one of the least important for humpback whales (albeit based on a small sample of humpback whale samples). Age 0 sprat and herring comprised a large proportion of the diet of both species, followed by older sprat (age 1–2) and older herring (age 2–4). An ecosystem based approach to fisheries management will be required in the CS if we seek effective conservation of both fin and humpback whales, and sustainable fisheries.
Geminivirus protein structure and function
Authors: Fondong Vincent N.
Published: April 2013

Geminiviruses are a family of plant viruses that cause economically important plant diseases worldwide. These viruses have circular single‐stranded DNA genomes and four to eight genes that are expressed from both strands of the double‐stranded DNA replicative intermediate. The transcription of these genes occurs under the control of two bidirectional promoters and one monodirectional promoter. The viral proteins function to facilitate virus replication, virus movement, the assembly of virus‐specific nucleoprotein particles, vector transmission and to counteract plant host defence responses. Recent research findings have provided new insights into the structure and function of these proteins and have identified numerous host interacting partners. Most of the viral proteins have been shown to be multifunctional, participating in multiple events during the infection cycle and have, indeed, evolved coordinated interactions with host proteins to ensure a successful infection. Here, an up‐to‐date review of viral protein structure and function is presented, and some areas requiring further research are identified.
Religion and ethno‐nationalism:Turkey'sKurdish issue
Authors: Sarigil Zeki , Fazlioglu Omer
Published: April 2013

One approach within theIslamic camp treatsIslam, which emphasizes overarching notions such as the ‘Islamic brotherhood’ and ‘ummah’, as incompatible with ethno‐nationalist ideas and movements. It is, however, striking that in the last decades, severalIslamic and conservative groups inTurkey have paid increasing attention to theKurdish issue, supporting their ethnic demands and sentiments. Even more striking, the leftist, secularKurdish ethno‐nationalists have adopted a more welcoming attitude towardIslam. How can we explain such intriguing developments and shifts? Using original data derived from several elite interviews and a public opinion survey, this study shows that the struggle forKurdish popular support and legitimacy has encouraged political elites from both camps to enrich their ideological toolbox by borrowing ideas and discourses from each other. Further,Turkish andKurdish nationalists alike utilizeIslamic discourses and ideas to legitimize their competing nationalist claims. Exploring such issues, the study also provides theoretical and policy implications.
Overweight, obesity and risk of premenopausal breast cancer according to ethnicity: a systematic review and dose‐response meta‐analysis
Authors: Amadou A. , Ferrari P. , Muwonge R. , Moskal A. , Biessy C. , Romieu I. , Hainaut P.
Published: April 2013

The association of overweight and obesity with premenopausal breast cancer remained unclear, ethnicity could play a role. A MEDLINE and PUBMED search of all studies on obesity and premenopausal breast cancer published from 2000 to 2010 was conducted. Dose‐response meta‐analysis was used to determine the risk of premenopausal breast cancer associated with different anthropometric measurements in different ethnic groups. For body mass index (BMI), each 5 kg m−2 increase was inversely associated with the risk of premenopausal breast cancer (RR = 0.95, 95% confidence interval [CI]: 0.94, 0.97). After stratification by ethnicity, the inverse association remained significant only among Africans (RR = 0.95, 95% CI: 0.91, 0.98) and Caucasians (RR = 0.93, 95% CI: 0.91, 0.95). In contrast, among Asian women, a significant positive association was observed. For waist‐to‐hip ratio (WHR), each 0.1 unit increase was positively associated with premenopausal breast cancer (RR = 1.08, 95% CI: 1.01, 1.16); the largest effect was detected in Asian women (RR = 1.19, 95% CI: 1.15, 1.24), while small effects of 5% and 6% were observed in African and Caucasian women, respectively. Our results suggest the importance of considering both fat distribution and ethnicity when studying premenopausal breast cancer.
Profound Sedation with Propofol Modifies Atrial Fibrillation Dynamics
Authors: CERVIGÓN RAQUEL , MORENO JAVIER , PÉREZ‐VILLACASTÍN JULIÁN , CASTELLS FRANCISCO
Published: April 2013

During atrial fibrillation (AF), multiple wandering propagation wavelets at high rates drift around both atria under controversial hierarchical models. Antiarrhythmic drugs modify the cardiac ionic currents supporting the fibrillation process within the atria, and can alter AF propagation dynamics and even terminate the arrhythmia. However, some other drugs, theoretically nonantiarrhythmic, may slightly block particular cardiac ionic currents through uncertain mechanisms in such a subtle way at regular heart rates that may have been pharmacologically overlooked. These potential effects might be better exposed at much higher activation rates as in AF, where atrial cells depolarize over 400 times per second. In this review, we aimed to compile and discuss results from several studies evaluating the net effect of profound sedation with propofol on atrial cells and atrioventricular (AV) conduction. Propofol is a very commonly used anesthetic agent, and its possible effect on AF dynamics has systematically not been taken into account in the myriad of clinical studies dealing with AF intracardiac recordings. The possible effect of sedation with propofol on AF was evaluated through the analysis of AF propagation patterns before and after its infusion in a series of patients submitted to pulmonary vein ablation. Effect on AV conduction will be discussed as well.
MERTK controls melanoma cell migration and survival and differentially regulates cell behavior relative to AXL
Authors: Tworkoski Kathryn A. , Platt James T. , Bacchiocchi Antonella , Bosenberg Marcus , Boggon Titus J. , Stern David F.
Published: April 2013

The receptor tyrosine kinase AXL regulates melanoma cell proliferation and migration. We now demonstrate that AXL and the related kinase MERTK are alternately expressed in melanoma and are associated with different transcriptional signatures. MERTK‐positive melanoma cells are more proliferative and less migratory than AXL‐positive melanoma cells and overexpression of AXL increases cell motility relative to MERTK. MERTK is expressed in up to 50% of melanoma cells and shRNA‐mediated knockdown of MERTK reduces colony formation and cell migration in a CDC42‐dependent fashion. Targeting MERTK also decreases cell survival and proliferation in an AKT‐dependent manner. Finally, we identify a novel mutation in the kinase domain of MERTK, MERTKP802S, that increases the motility of melanoma cells relative to wild‐type MERTK. Together, these data demonstrate that MERTK is a possible therapeutic target in melanoma, that AXL and MERTK are associated with differential cell behaviors, and that mutations in MERTK may contribute to melanoma pathogenesis.
T cell immunotherapy for melanoma from bedside to bench to barn and back: how conceptual advances in experimental mouse models can be translated into clinical benefit for patients
Authors: Tüting Thomas
Published: April 2013

A solid scientific basis now supports the concept that cytotoxic T lymphocytes can specifically recognize and destroy melanoma cells. Over the last decades, clinicians and basic scientists have joined forces to advance our concepts of melanoma immunobiology. This has catalyzed the rational development of therapeutic approaches to enforce melanoma‐specific T cell responses. Preclinical studies in experimental mouse models paved the way for their successful translation into clinical benefit for patients with metastatic melanoma. A more thorough understanding of how melanomas develop resistance to T cell immunotherapy is necessary to extend this success. This requires a continued interdisciplinary effort of melanoma biologists and immunologists that closely connects clinical observations with in vitro investigations and appropriate in vivo mouse models: From bedside to bench to barn and back.
Photogrammetric Monitoring of an Artificially Generated Shallow Landslide
Authors: Akca Devrim
Published: April 2013

An artificial rainfall event was applied to a forested slope in Ruedlingen, northern Switzerland. The experiment triggered a landslide which resulted in mobilising about 130 m3 of debris. The event was monitored by a photogrammetric network of four cameras, operating at 5 to 8 frames per second, in order to quantify spatial and temporal changes by tracking tennis balls pegged into the ground. Image measurements were performed using automated image matching methods, implemented through a software package developed in‐house. Three‐dimensional coordinates of the target points were estimated by running a customised type of bundle adjustment, achieving a positioning precision of ± 1·8 cm.
Survey on the prevalence of Rhizoctonia spp. in European soils and determination of the baseline sensitivity towards sedaxane
Authors: Goll M. B. , Schade‐Schütze A. , Swart G. , Oostendorp M. , Schott J. J. , Jaser B. , Felsenstein F. G.
Published: April 2013

The prevalence of Rhizoctonia spp. in European soils was determined by analysing soil samples from 282 locations. Rhizoctonia spp. were found in 68% of these samples from France, Germany, the UK, Poland, Italy, Spain, Hungary and the Czech Republic. Samples from 136 locations were further analysed by pyrosequencing. Seventy‐six percent of the isolates were Rhizoctonia solani and 24% binucleate Rhizoctonia spp. Rhizoctonia solani anastomosis group (AG) 5 was detected most frequently (25%), followed by AG 9 (16%) and AG 4 (13%). For the binucleate Rhizoctonia spp., AG E was most prevalent (13%). Rhizoctonia cerealis was not detected in soil samples. Soil type or cropping history had no effect on the type of Rhizoctonia observed. Rhizoctonia solani AG 5 was the most frequently detected AG irrespective of the previous crop. The spectrum of AGs detected was similar for France, Germany and Poland but was significantly different for the UK (P = 0·0016). Finally, the baseline sensitivity towards sedaxane, a new active ingredient for seed treatment, was analysed for all isolates. The results indicate a low baseline sensitivity (average EC50 of 0·028 p.p.m.) for all Rhizoctonia AGs. No difference in sensitivity was observed with the isolates obtained from different countries.
Can stem cells be used to generate new lungs? Ex vivo lung bioengineering with decellularized whole lung scaffolds
Authors: Wagner Darcy E. , Bonvillain Ryan W. , Jensen Todd , Girard Eric D. , Bunnell Bruce A. , Finck Christine M. , Hoffman Andrew M. , Weiss Daniel J.
Published: April 2013

For patients with end‐stage lung diseases, lung transplantation is the only available therapeutic option. However, the number of suitable donor lungs is insufficient and lung transplants are complicated by significant graft failure and complications of immunosuppressive regimens. An alternative to classic organ replacement is desperately needed. Engineering of bioartificial organs using either natural or synthetic scaffolds is an exciting new potential option for generation of functional pulmonary tissue for human clinical application. Natural organ scaffolds can be generated by decellularization of native tissues; these acellular scaffolds retain the native organ ultrastructure and can be seeded with autologous cells towards the goal of regenerating functional tissues. Several decellularization strategies have been employed for lungs; however, there is no consensus on the optimal approach. A variety of cell types have been investigated as potential candidates for effective recellularization of acellular lung scaffolds. Candidate cells that might be best utilized are those which can be easily and reproducibly isolated, expanded in vitro, seeded onto decellularized matrices, induced to differentiate into pulmonary lineage cells, and which survive to functional maturity. Whole lung cell suspensions, endogenous progenitor cells, embryonic and adult stem cells and induced pluripotent stem (iPS) cells have been investigated for their applicability to repopulate acellular lung matrices. Ideally, patient‐derived autologous cells would be used for lung recellularization as they have the potential to reduce the need for post‐transplant immunosuppression. Several studies have performed transplantation of rudimentary bioengineered lung scaffolds in animal models with limited, short‐term functionality but much further study is needed.
Trabecular Pattern of the Proximal Ulna: A Morphological Study
Authors: Zafiropoulos George T. , Prasad Kodali Siva R. K.
Published: April 2013

Background

The trabecular architecture of the olecranon and proximal ulna has not been studied in detail. We undertook a primarily cadaveric study aiming to link with the theory of biomechanics.

Methods

Eight pairs of ulnae were obtained from cadavers. Half of the ulnae were sliced longitudinally, each slice 2 mm to 3 mm thick (Group I), and the remaining half were sliced vertically (Group II) and radiographed to study the trabecular orientation of the olecranon and proximal ulna. Computerized tomography (CT) scans of eight patients (Group III) were studied to determine the real-life trabecular pattern.

Results

In Group I, two main sets of trabeculae were observed. The first set of trabeculae consists of three bundles, which arise from the anterior cortex. Anterior and middle bundles support the subarticular subchondral area. The posterior bundle curves and spreads to posterior cortex. The second set arises from posterior cortex and terminates under subchondral area. In Group II, trabeculae subtend a 90° angle to the articular surface. CT (Group III) confirmed the cadaveric observations.

Conclusions

Trabeculae of the olecranon and proximal ulna comprise a cluster that resists compressive loading and a further cluster that resists tensile stresses, which should be taken into consideration in the prosthetic design of elbow replacement to facilitate stress absorption.
Signatures of biologically influenced CaCo3 and Mg–Fe silicate precipitation in hot springs: Case study from the Ruidian geothermal area, western Yunnan Province, China
Authors: Jones Brian , Peng Xiaotong
Published: April 2013

Hot springs at Gongxiaoshe and Zhuyuan (maximum temperatures of 73 to 84°C, respectively) are characterized by deposits formed of calcite, aragonite, non‐crystalline Si–Mg–Fe deposits, and minor amounts of barite and gypsum. The deposits at Gongxiaoshe are formed largely of alternating calcite and aragonite laminae, whereas those at Zhuyuan are formed largely of calcite. The calcite is in the form of: (i) pseudodendrites that grew as sub‐crystals stacked upon each other; and (ii) unattached euhedral and incompletely formed dodecahedral and rhombohedral crystals. Amorphous CaCO3, formed of nanoparticles <1 μm long, is common in some of the Zhuyuan deposits, but minor in the Gongxiaoshe deposits. The morphologically diverse arrays of aragonite crystals that lie parallel to bedding were not nucleated on a growth surface. Many substrates in these deposits are covered with reticulate coatings that are formed largely of Si and Mg with minor Fe and micro‐granular coatings that are formed largely of Si and Fe. Biofilms, with their extracellular polymeric substances, and microbes are common at both springs. The compositionally and crystallographically diverse precipitates at these two springs are attributed to a biologically influenced model with precipitation taking place in micro‐domains that developed in the extracellular polymeric substances. According to this model, precipitation varied at the micron‐scale influenced by the elemental concentrations that developed in the hydrogel of extracellular polymeric substances. Critically, the very low preservation potential of the extracellular polymeric substance and its formative microbes means that the precipitates will rapidly lose evidence of their biotic origin. The compositional diversity of the precipitates, the crystallographic diversity of the calcite and aragonite with numerous incompletely formed crystals, and local concentrations of Si, Mg and Fe may, however, serve as proxies of that biologically influenced precipitation.
Spatial Integration and Functional Balance in Polycentric Urban Systems: A Multi‐Scalar Approach
Authors: Vasanen Antti
Published: April 2013

Research on polycentricity has focused increasingly on the multi‐scalar functional organisation of polycentric urban systems. These studies have shown that the degree of functional polycentricity varies considerably across different spatial scales. Moreover, functional polycentricity is linked to two distinct concepts: spatial integration and the balanced distribution of flows. The aim of this paper is to clarify the relation between these two concepts and to highlight the implications of this conceptual distinction for empirical research across different scales. The paper examines the connectivity field method developed to measure spatial interaction in polycentric urban systems. Using detailed commuting data, the feasibility of the method in measuring both spatial integration and the balanced distribution of flows across different scales is tested in a case study from southern Finland.
A TIR–NBS protein encoded by Arabidopsis Chilling Sensitive 1 (CHS1) limits chloroplast damage and cell death at low temperature
Authors: Zbierzak Anna Maria , Porfirova Svetlana , Griebel Thomas , Melzer Michael , Parker Jane E. , Dörmann Peter
Published: April 2013

Survival of plants at low temperature depends on mechanisms for limiting physiological damage and maintaining growth. We mapped the chs1‐1 (chilling sensitive1‐1) mutation in Arabidopsis accession Columbia to the TIR‐NBS gene At1g17610. In chs1‐1, a single amino acid exchange at the CHS1 N‐terminus close to the conserved TIR domain creates a stable mutant protein that fails to protect leaves against chilling stress. The sequence of another TIR‐NBS gene (At5g40090) named CHL1 (CHS1‐like 1) is related to that of CHS1. Over‐expression of CHS1 or CHL1 alleviates chilling damage and enhances plant growth at moderate (24°C) and chilling (13°C) temperatures, suggesting a role for both proteins in growth homeostasis. chs1‐1 mutants show induced salicylic acid production and defense gene expression at 13°C, indicative of autoimmunity. Genetic analysis of chs1‐1 in combination with defense pathway mutants shows that chs1‐1 chilling sensitivity requires the TIR‐NBS‐LRR and basal resistance regulators encoded by EDS1 and PAD4 but not salicylic acid. By following the timing of metabolic, physiological and chloroplast ultrastructural changes in chs1‐1 leaves during chilling, we have established that alterations in photosynthetic complexes and thylakoid membrane integrity precede leaf cell death measured by ion leakage. At 24°C, the chs1‐1 mutant appears normal but produces a massive necrotic response to virulent Pseudomonas syringae pv. tomato infection, although this does not affect bacterial proliferation. Our results suggest that CHS1 acts at an intersection between temperature sensing and biotic stress pathway activation to maintain plant performance over a range of conditions.
How we manage AB plasma inventory in the blood center and transfusion service
Authors: Yazer Mark , Eder Anne F. , Land Kevin J.
Published: April 2013

The growing use of group AB plasma in the United States in recent years poses unique challenges to blood centers and transfusion services. Blood centers must collect sufficient plasma components from a limited pool of group AB donors while taking steps to improve transfusion safety that further restricts the available supply. Transfusion services, on the other hand, must use the finite resource in the most conscientious and medically appropriate manner. Recently, many investigations have challenged long‐held beliefs about transfusion practice and appropriate indications for blood components across a variety of specialties. Balancing supply and demand of group AB plasma requires collaboration between blood suppliers and transfusion services, and opportunities for improvement exist on both sides of the equation.
Influence of tranexamic acid on postoperative autologous blood retransfusion in primary total hip and knee arthroplasty: a randomized controlled trial
Authors: Oremus Kresimir , Sostaric Sinisa , Trkulja Vladimir , Haspl Miroslav
Published: April 2013

Background

Postoperatively shed blood salvage is commonly used to reduce allogenic blood transfusion in patients undergoing total hip (THA) and knee arthroplasty (TKA). Autologous blood retransfusion is not devoid of risk. We hypothesized that adding tranexamic acid (TXA) to a restrictive blood transfusion protocol would reduce the need for postoperative autologous blood retransfusion in primary knee and hip arthroplasty.

Study Design and Methods

Ninety‐eight adult patients undergoing primary THA or TKA were randomly assigned to receive an intraoperative intravenous loading dose of 1.0 g of TXA followed by another 1.0‐g dose 3 hours later (TXA group) or a matching volume 0.9% saline placebo (control group). A postoperatively shed autologous blood recovery system was used in all patients and the minimum reinfusion volume set at 250 mL. Red blood cells were transfused if hemoglobin level was less than 8 or if 8 to 10 g/dL with symptoms of anemia.

Results

The proportion of patients receiving autologous blood reinfusion was significantly lower in the TXA group (5/49) compared to placebo (42/49) with an absolute difference of −75.5% (adjusted relative risk, 0.005), and none of the patients in the TXA group received more than 400 mL retransfused. Median total external blood loss during the first 24 hours was lower in the TXA group, 320 mL (range, 80‐930 mL), compared to 970 mL (range, 100‐2600 mL) in the placebo group (p < 0.001). There were no significant differences in homologous blood transfusions and hematologic variables between groups. Treatment differences were consistent by size and significance when the analysis was repeated separately in patients undergoing TKA or THA.

Conclusion

Addition of TXA to a restrictive transfusion protocol makes the use of a postoperative blood salvage system in patients undergoing primary hip and knee arthroplasty unnecessary.
Pilot clinical study of carmustine associated with a lipid nanoemulsion in combination with vincristine and prednisone for the treatment of canine lymphoma
Authors: Lucas S. R. R. , Maranhão R. C. , Guerra J. L. , Coelho B. M. P. , Barboza R. , Pozzi D. H. B.
Published: April 2013

A lipid nanoemulsion (LDE) resembling low‐density lipoprotein can target malignant tumours. Inin vivoand clinical studies, association of chemotherapeutic agents toLDEdecreased their toxicity and increased pharmacological action. Here, safety ofLDEas carmustine carrier (50 mg m−2, intravenous) combined with vincristine and prednisone for the treatment of dogs with lymphoma was tested and compared with commercial carmustine with vincristine and prednisone. In five dogs fromLDE‐carmustine and six from commercial carmustine, complete remission was achieved (P> 0.05). Partial remission occurred in two dogs from each group. In both groups, the median progression‐free intervals (119 and 199 days) and overall survival times (207 and 247 days) were equal. Neutropenia was observed in both groups, but no other major toxicities occurred. Therefore, no difference was observed between the treatments.LDE‐carmustine was shown to be safe and effective in a drug combination protocol, which encourages larger studies to investigate the use of this novel formulation to treat canine lymphomas.
Development and characterization of monoclonal antibodies to subgroup A avian leukosis virus
Authors: Qiu Y. , Li X. , Fu L. , Cui Z. , Li W. , Wu Z. , Sun S.
Published: April 2013

Avian leukosis virus subgroup A (ALV‐A) is a retrovirus which infects egg‐type chickens and is the main pathogen of lymphoid leukosis (LL) and myeloid leukosis (ML). In order to greatly enhance the diagnosis and treatment of clinical avian leukemia, two monoclonal antibodies (MAbs) to ALV‐A were developed by fusion between SP2/0 and spleen cells from mice immunized with expressed ALV‐A env‐gp85 protein. Using immunofluorescence assay (IFA), two MAbs reacted with ALV‐A, but not with subgroups B and J of ALV. Western blot tests showed that molecular weight of ALV‐A envelope glycoprotein recognized by MAbs was about 53 kD. Isotyping test revealed that two MAbs (A5C1 and A4C8) were IgG1 isotypes. These MAbs can be used for diagnosis and epidemiology of ALV‐A.
Comparison of three staining methods to identify eosinophils in formalin‐fixed canine skin
Authors: Gomes Paulo , Torres Sheila M. F. , Plager Douglas A. , Jessen Carl R. , Lee James J.
Published: April 2013

Background

Studies comparing the ability of staining methods to detect eosinophils in formalin‐fixed canine skin are lacking.

Hypothesis/Objectives

The aim of this study was to compare the effectiveness of eosinophil peroxidase monoclonal antibody (EPXmAb), Luna and haematoxylin and eosin (H&E) to detect eosinophils in fixed canine skin by assessing the following parameters: (i) specificity of eosinophil staining; (ii) extracellular eosinophil granule staining; (iii) tissue background staining; (iv) contrast between eosinophil and surrounding tissue staining; and (v) differences in the number of eosinophils detected by each stain.

Methods

Three serial sections of formalin‐fixed, paraffin‐embedded tissues of predominantly eosinophilic skin diseases (n = 8), noneosinophilic skin diseases (n = 7) and normal canine skin (n = 1) were stained with the three stains. Each parameter was independently assessed and scored by two investigators.

Results

Luna and EPXmAb were specific in detecting eosinophils. The EPXmAb was significantly more effective than Luna (P < 0.001) and H&E (P < 0.001) in its ability to detect extracellular eosinophil granules (i.e. to detect intact and released eosinophil granules). The EPXmAb showed significantly less background staining compared with Luna (P = 0.0005). Moreover, significantly more stain contrast was noted with EPXmAb compared with Luna (P = 0.003) and H&E (P < 0.001). There was no significant difference between the mean eosinophil counts among the three stains.

Conclusion and clinical importance

The three stains were shown to be useful to detect and quantify eosinophils in fixed canine skin. The EPXmAb‐based immunohistochemical stain proved to be a novel tool to detect eosinophils in canine skin.
Environmental flows in two highly regulated rivers: the Hawkesbury Nepean in Australia and the Durance in France
Authors: Warner Robin Frederick
Published: April 2013

Environmental flows are waters released from storages to improve degraded ecosystems. Subsequent monitoring is then used to determine incremental benefits. These flows in the Hawkesbury Nepean and the Durance are very low compared with those advocated for other systems. In the former, water is used in Sydney and Wollongong, while the Durance water is diverted to supply 16 hydropower stations. In this system, reserved flows have been set at 2.5% of mean discharge, while in the Australian river, environmental flows have varied, but are usually 3.6% or less in the current regime. Additionally, increasing the transparencies of barrages and weirs will enhance the effectiveness of current environmental flows. Implementation of such flows imposes many problems because of structural difficulties for releasing water and compromising regulatory infrastructures. Additionally, with the onset of global warming, both systems will suffer significant water losses.
A virtual trial framework for quantifying the detectability of masses in breast tomosynthesis projection data
Authors: Young Stefano , Bakic Predrag R. , Myers Kyle J. , Jennings Robert J. , Park Subok
Published: April 2013

Purpose:

Digital breast tomosynthesis (DBT) is a promising breast cancer screening tool that has already begun making inroads into clinical practice. However, there is ongoing debate over how to quantitatively evaluate and optimize these systems, because different definitions of image quality can lead to different optimal design strategies. Powerful and accurate tools are desired to extend our understanding of DBT system optimization and validate published design principles.

Methods:

The authors developed a virtual trial framework for task‐specific DBT assessment that uses digital phantoms, open‐source x‐ray transport codes, and a projection‐space, spatial‐domain observer model for quantitative system evaluation. The authors considered evaluation of reconstruction algorithms as a separate problem and focused on the information content in the raw, unfiltered projection images. Specifically, the authors investigated the effects of scan angle and number of angular projections on detectability of a small (3 mm diameter) signal embedded in randomly‐varying anatomical backgrounds. Detectability was measured by the area under the receiver‐operating characteristic curve (AUC). Experiments were repeated for three test cases where the detectability‐limiting factor was anatomical variability, quantum noise, or electronic noise. The authors also juxtaposed the virtual trial framework with other published studies to illustrate its advantages and disadvantages.

Results:

The large number of variables in a virtual DBT study make it difficult to directly compare different authors’ results, so each result must be interpreted within the context of the specific virtual trial framework. The following results apply to 25% density phantoms with 5.15 cm compressed thickness and 500 μm3 voxels (larger 500 μm2 detector pixels were used to avoid voxel‐edge artifacts): 1. For raw, unfiltered projection images in the anatomical‐variability‐limited regime, AUC appeared to remain constant or increase slightly with scan angle. 2. In the same regime, when the authors fixed the scan angle, AUC increased asymptotically with the number of projections. The threshold number of projections for asymptotic AUC performance depended on the scan angle. In the quantum‐ and electronic‐noise dominant regimes, AUC behaviors as a function of scan angle and number of projections sometimes differed from the anatomy‐limited regime. For example, with a fixed scan angle, AUC generally decreased with the number of projections in the electronic‐noise dominant regime. These results are intended to demonstrate the capabilities of the virtual trial framework, not to be used as optimization rules for DBT.

Conclusions:

The authors have demonstrated a novel simulation framework and tools for evaluating DBT systems in an objective, task‐specific manner. This framework facilitates further investigation of image quality tradeoffs in DBT.
Direct Proteomic Quantification of the Secretome of Activated Immune Cells
Authors: Meissner Felix , Scheltema Richard A. , Mollenkopf Hans-Joachim , Mann Matthias
Published: April 2013

Tracking Secreted Proteins

The proteins secreted by cells provide a flow of information within tissues and are thus of particular interest. However, systematic detection of secreted proteins is tricky because they tend to be present in small amounts within complex mixtures of proteins where other components are very abundant.

Meissner
et al.

(p.
475
) developed a method for screening the secreted proteins from cultured mouse macrophages in response to cues that cause inflammation. The amount of contaminating proteins was reduced by culturing the cells without added serum and then sensitive mass spectrometry techniques were used to detect and quantify secretion of nearly 800 different proteins. Secretion was compared from cells lacking the signaling adaptor proteins MyD88 or TRIF, or both. Secretion of some proteins were regulated redundantly and were secreted without one of the adaptors, but others required both signals for release. Some anti-inflammatory proteins were released at later times in response to synergistic signals from both adaptor proteins, perhaps as a fail-safe mechanism to prevent excessive inflammation.
Comment on “In Monkeys Making Value-Based Decisions, LIP Neurons Encode Cue Salience and Not Action Value”
Authors: Newsome William T. , Glimcher Paul W. , Gottlieb Jacqueline , Lee Daeyeol , Platt Michael L.
Published: April 2013

Leathers and Olson (Reports, 5 October 2012, p. 132) draw the strong conclusion that neurons in the monkey lateral intraparietal (LIP) cortical area encode only cue salience, and not action value, during value-based decision-making. Although their findings regarding cue salience are interesting, their broader conclusions are problematic because (i) their primary conclusion is based on responses observed during a brief interval at the beginning of behavioral trials but is extended to all subsequent temporal epochs and (ii) the authors failed to replicate basic hallmarks of LIP physiology observed in those subsequent temporal epochs by many laboratories.
Response to Comment on “In Monkeys Making Value-Based Decisions, LIP Neurons Encode Cue Salience and Not Action Value”
Authors: Leathers Marvin L. , Olson Carl R.
Published: April 2013

Newsome
et al
. question neither our key result, that large-penalty cues elicited stronger responses than small-penalty cues, nor our key conclusion, that neurons early in the trial signaled cue salience and not action value. Instead, they focus on subsequent neuronal activity. The patterns of delay-period activity that they note can be explained by reference to experimental methodology.
Melting of Iron at Earth’s Inner Core Boundary Based on Fast X-ray Diffraction
Authors: Anzellini S. , Dewaele A. , Mezouar M. , Loubeyre P. , Morard G.
Published: April 2013

Hot Enough to Melt Iron

Earth's core is divided into a fluid outer core and a solid inner core, both composed predominately of iron at extremely high pressures and temperatures. The boundary between these two regions is largely controlled by the melting point of iron at ∼330 GPa, which in turn influences heat transfer and geodynamo generation.

Anzellini
et al.

(p.
464
, see the Perspective by
Fei
) compressed iron in a laser-heated diamond anvil cell, tracking its structure and texture by using time-resolved x-ray diffraction as the pressure increased to 200 GPa. The melting curve suggests the possibility of high heat flux and partial melting at the core-mantle boundary.
Observations of Ejecta Clouds Produced by Impacts onto Saturn’s Rings
Authors: Tiscareno Matthew S. , Mitchell Colin J. , Murray Carl D. , Di Nino Daiana , Hedman Matthew M. , Schmidt Jürgen , Burns Joseph A. , Cuzzi Jeffrey N. , Porco Carolyn C. , Beurle Kevin , Evans Michael W.
Published: April 2013

Saturn's Meteoroid Crash

During Saturn's equinox in 2009, when the Sun illuminated its rings edge-on, images taken by the Cassini spacecraft showed dust clouds appearing as bright streaks above the rings. Similar streaks were detected in 2005 and 2012 when Cassini observed the C ring at close range.

Tiscareno
et al.

(p.
460
) suggest that the cause of each observed feature is likely to be the impact of a stream of recently disrupted material originating from a meteoroid impact onto the ring and derive the influx rate of meteoroids at Saturn.
Neurotransmitter Switching in the Adult Brain Regulates Behavior
Authors: Dulcis Davide , Jamshidi Pouya , Leutgeb Stefan , Spitzer Nicholas C.
Published: April 2013

Daylight Determines Dopamine

Expression of the appropriate neurotransmitters is essential for the function of neural circuits. Can neurons change their transmitter phenotype to deal with alterations in the environment?

Dulcis
et al.

(p.
449
; see the Perspective by

Birren and Marder

) exposed adult rats to different photoperiods mimicking summer and winter daylengths. Neurotransmitter expression switched between dopamine and somatostatin in hypothalamic neurons that regulate release of corticotropin-releasing factor. Transmitter switching occurred at the transcriptional level and was accompanied by changes in postsynaptic receptors.
Melting Earth's Core
Authors: Fei Yingwei
Published: April 2013

Studies of melting iron at extreme temperature and pressure provide a better understanding of the temperature of Earth's core.

[Also see Report by

Anzellini
et al.

]
Are Gold Clusters in RF Fields Hot or Not?
Authors: Kim Hong Koo , Hanson George W. , Geller David A.
Published: April 2013

Heating of gold nanoparticles by radio-frequency waves, which is of interest for clinical applications, can occur if the nanoparticles are made magnetic.
Animal Conformists
Authors: de Waal Frans B. M.
Published: April 2013

Field studies show that both whales and vervet monkeys acquire feeding behaviors through social learning.

[Also see Reports by
de Waal
et al.
and

Allen
et al.

]
Plasticity in the Neurotransmitter Repertoire
Authors: Birren Susan J. , Marder Eve
Published: April 2013

A switch in the type of neurotransmitter released in the brain underlies changes in mammalian behavior associated with day-night cycles.

[Also see Research Article by

Dulcis
et al.

]
Young Researchers in Japan
Authors: Nagata Naoki , Yamanaka Shinya
Published: April 2013

Next month in Tokyo, Asia's largest biotechnology event will take place—the International Bio Technology Exhibition and Conference. Japan's traditional strength in both biology and technology makes it a very appropriate site for this forum. But over the long term, Japan's science and technology future will require that our nation place a much stronger focus on encouraging risk taking and independence for promising young scientists.
Deep Dig Shows Maya Architecture Arose Independently of Olmec's
Authors: Pringle Heather
Published: April 2013

Arrangement of urban ceremonial space reveals Maya sophistication that was probably not adopted from the Olmec.
Public Enemy Number One
Authors: Stone Richard
Published: April 2013

North Korea has one of the highest TB rates outside sub-Saharan Africa and a burgeoning drug-resistance problem. A remarkable unusual collaboration is hoping to turn the tide.
When Early Hominins Got a Grip
Authors: Gibbons Ann
Published: April 2013

Paleoanthropologists announced a modern feature in a rare, 1.4-million-year-old hand bone from Kenya, filling a 1-million-year gap in the fossil record and showing when key adaptations to toolmaking arose.
Integrating the Xpert MTB/RIF Assay into a Diagnostic Workflow for Rapid Detection of Mycobacterium tuberculosis in a Low-Prevalence Area
Authors: Deggim Vanessa , Somoskovi Akos , Voit Antje , Böttger Erik C. , Bloemberg Guido V.
Published: April 2013

The Xpert MTB/RIF assay is a rapid and fully automated real-time PCR assay. The performance of the Xpert MTB/RIF assay as a primary screening test for urgent clinical specimens was evaluated during a 2-year period. The results showed that replacing smear microscopy with the Xpert MTB/RIF assay facilitates laboratory handling and improves the sensitivity and specificity of
Mycobacterium tuberculosis
detection.
Endemic Genotypes of Candida albicans Causing Fungemia Are Frequent in the Hospital
Authors: Escribano Pilar , Rodríguez-Créixems Marta , Sánchez-Carrillo Carlos , Muñoz Patricia , Bouza Emilio , Guinea Jesús
Published: April 2013

Genotyping of
Candida albicans
strains causing candidemia can uncover the presence of endemic genotypes in the hospital. Using a highly reproducible and discriminatory microsatellite marker panel, we studied the genetic diversity of 217
C. albicans
isolates from the blood cultures of 202 patients with candidemia (from January 2007 to December 2011). Each isolate represented 1 candidemia episode. Multiple episodes were defined as the isolation of
C. albicans
in further blood cultures taken ≥7 days after the last isolation in blood culture. Of the 202 patients, 188 had 1 episode, 13 had 2 episodes, and 1 had 3 episodes. Identical genotypes showed the same alleles for all 6 markers. The genotypes causing both episodes were identical in most patients with 2 episodes (11/13; 84.6%). In contrast, 2 different genotypes were found in the patient with 3 episodes, one causing the first and second episodes and the other causing the third episode (isolated 6 months later). We found marked genetic diversity in 174 different genotypes: 155 were unique, and 19 were endemic and formed 19 clusters (2 to 6 patients per cluster). Up to 25% of the patients were infected by endemic genotypes that infected 2 or more different patients. Some of these endemic genotypes were found in the same unit of the hospital, mainly neonatology, whereas others infected patients in different wards.
Epitopes of the Highly Immunogenic Trichomonas vaginalis α-Actinin Are Serodiagnostic Targets for Both Women and Men
Authors: Neace Calvin J. , Alderete J. F.
Published: April 2013

There is a need for a point-of-care serodiagnostic test for women and men for sexually transmitted infections (STIs) caused by
Trichomonas vaginalis
. Sera from women with this STI and sera from men that were analyzed in studies showing a relationship between serostatus and prostate cancer are highly seropositive in response to trichomonad α-actinin and its truncated protein (ACT-P2) (positive control sera). Epitope mapping experiments showed that positive control sera from women had antibodies to 13 distinct epitopes, 5 of which were detected by positive control sera from men. Sera from women and men that were unreactive with α-actinin (negative control sera) failed to detect any of the epitopes or other α-actinin amino acid sequences. The
T. vaginalis
α-actinin amino acid sequence and the sequences of the epitopes showed little or no identity with those of other proteins of microbial pathogens or the human α-actinin 1 (HuACTN1) homolog. Immunoassays such as dot blot, immunoblot, and enzyme-linked immunosorbent assays were used. Positive control sera did not detect HuACTN1 in immunoassays, and the range of levels of identity of α-actinin epitopes with HuACTN1 was 0% to 50%. Comparison of the
T. vaginalis
α-actinin epitopes with proteins in data banks, such as
Tritrichomonas suis
,
Candida albicans
, and
Saccharomyces cerevisiae
proteins, gave a range of identity levels of 0% to 22%. Specific 15-mer peptide epitopes of α-actinin with low to no identity with other proteins were synthesized and were reactive with positive control sera only. These findings identify epitopes of α-actinin as candidate serodiagnostic targets and suggest strongly that a highly seropositive reaction to α-actinin suggests exposure to
T. vaginalis
.