bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantum dynamics of quantum bits
Authors: Nguyen Bich Ha 
Published: July 2011

Abstract
The theory of coherent oscillations of the matrix elements of the density matrix of the two-state system as a quantum bit is presented. Different calculation methods are elaborated in the case of a free quantum bit. Then the most appropriate methods are applied to the study of the density matrices of the quantum bits interacting with a classical pumping radiation field as well as with the quantum electromagnetic field in a single-mode microcavity. The theory of decoherence of a quantum bit in Markovian approximation is presented. The decoherence of a quantum bit interacting with monoenergetic photons in a microcavity is also discussed. The content of the present work can be considered as an introduction to the study of the quantum dynamics of quantum bits.
Low temperature growth and properties of ZnO nanorod arrays
Authors: Wu Xiang , Chen Huibo , Gong Lihong , Qu Fengyu , Zheng Yufeng 
Published: July 2011

Abstract
In this paper, well aligned ZnO nanorod arrays were synthesized by a simple hydrothermal route at a low temperature. The diameters of the as-synthesized products were 20–60 nm and the lengths were as much as several micrometers. The surfaces and tops of the nanorods were smooth. The as-grown nanorod arrays were investigated by x-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), photoluminescence (PL) spectroscopy and contact angle (CA) analysis. The as-grown nanorods were single crystalline structures with a wurtzite phase, and grew along the [0001] direction. The PL spectrum with only one strong peak at 383 nm shows good intrinsic emission.
Single-walled carbon nanotubes synthesized by chemical vapor deposition of C2H2 over an Al2O3 supported mixture of Fe, Mo, Co catalysts
Authors: Cao Thi Thanh , Ngo Thi Thanh Tam , Nguyen Van Chuc , Than Xuan Tinh , Nguyen Ba Thang , Phan Ngoc Minh 
Published: July 2011

Abstract
Single-walled carbon nanotubes (SWCNTs) have been successfully synthesized by chemical vapor deposition (CVD) using acetylene (C2H2) gas as a carbon source and a mixture of Fe/Mo/Co on an Al
2
O
3 support as a catalyst. The effects of the weight percentage (wt%) of metals in the Fe/Mo/Co/Al
2
O
3 catalysts, growth time, gas flow rate and growth temperature on SWCNT growth were studied in detail. The optimum growth conditions were found to be a growth time of 60 min, a growth temperature of 750 °C, Ar/H
2/C
2
H
2 flow rates of 420/100/14 sccm and a catalyst composition of Fe/Mo/Co/Al
2
O
3=5/3/1/80 (wt%). The morphologies and structures of the grown SWCNTs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy techniques.
spacodiR: structuring of phylogenetic diversity in ecological communities
Authors: Eastman Jonathan M. , Paine C. E. Timothy , Hardy Olivier J. 
Published: July 2011

Abstract
Motivation: spacodiR is a cross-platform package, written for the R environment, for studying partitioning of diversity among natural communities in space and time. Complementing and extending existing software, spacodiR allows for hypothesis testing and parameter estimation in studying spatial structuring of species-, phylogenetic- and trait diversities.
Availability: Integrated with other software in the R environment and with well documented and demonstrated functions, spacodiR is an open-source package and available at http://cran.r-project.org.
Contact: jonathan.eastman@gmail.com; ohardy@ulb.ac.be
Fallacies and false premises—a critical assessment of the arguments for the recognition of paraphyletic taxa in botany
Authors: Schmidt‐Lebuhn Alexander N. 
Published: July 2011

AbstractOne of the central controversies in contemporary taxonomy and systematics revolves around whether to accept or to reject paraphyletic taxa. The present review is the result of a survey of the ongoing discussion in botany over the past ca. 15 years, and attempts to systematically and critically assess all individual arguments presented for the formal recognition of paraphyletic groups in the classification of life. Where arguments are found to be without merit, rebuttals are presented in the hope of excluding them from further discussion, which can then concentrate on those that have merit. Where arguments are found to be sound, their implications and possible solutions are discussed. The controversy around paraphyletic taxa can be broken down into three questions: whether their rejection or acceptance would lead to a classification better reflecting patterns of biological diversity and evolutionary history; whether their rejection or acceptance would lead to a more practical, useful and predictive classification; and whether their rejection is compatible with ranked and binary Linnaean taxonomy. All available arguments for paraphyletic taxa relating to the first question are demonstrated to be based on various logical fallacies or false premises, especially misunderstandings of the principles of phylogenetic systematics. The issue of usefulness is harder to resolve, as different classifications serve different needs. It is presumably unavoidable but also preferable that phylogenetic and non‐phylogenetic ways of classifying species continue to coexist, serving different needs. Finally, an insistence on monophyletic taxa is found to be incompatible with binary taxonomy under a set of very specific circumstances and assumptions whose presence and accuracy are not universally accepted.© The Willi Hennig Society 2011.
Body cavity fluid can induce epithelial and mesothelial differentiation from CD34 positive peripheral blood stem cells in vitro
Authors: Kataoka H. , Kobayashi T. K. , Amano S. , Yamada E. , Ishida M. , Kushima R. , Okabe H. 
Published: July 2011

H. Kataoka, T. K. Kobayashi, S. Amano, E. Yamada, M. Ishida, R. Kushima and H. OkabeBody cavity fluid can induce epithelial and mesothelial differentiation from CD34 positive peripheral blood stem cells in vitroObjective:  Primary culture of CD34 positive stem cells collected from human peripheral blood was performed with and without supplementation with concentrated ascitic fluid; morphological and immunocytochemical pictures of cultured cells were taken chronologically and compared.Methods:  CD34‐positive stem cells collected from peripheral blood were cultured for 1, 24 and 48 hours. Concentrated ascitic fluid was added to the plates for the 24‐and 48‐hour cultures. For immunocytochemical studies, CD34, AE1/AE3, Ber‐Ep4 (EA), EMA, EGFR, CD31, CA125 and D2‐40 monoclonal antibodies were used.Results:  After culture, small round cells with naked nuclei began to enlarge and to exhibit various changes in the cytoplasm and nucleus. Supplementation with concentrated body cavity fluid enhanced these changes. CD34‐positive cells with small round cell features were detected 1 hour after culture and these had no epithelial or mesothelial markers. After 24 hours, CD34‐positive cells had disappeared and cells weakly positive for EGFR, EMA, CA125 and D2‐40 were detected. Cells with strong and moderate positive reactions for EGFR, AE1/AE3, EA, EMA, D2‐40 and CA125 were detected after 48 hours. Supplementation with concentrated body cavity fluid increased the intensity and number of positive cells for these markers compared with the control group. The positive reaction, not only for the epithelial markers such as EGFR and AE1/AE3, but also for mesothelial markers such as CA125 and D2‐40, was found to be increased in small numbers of cells in direct proportion to the duration of the primary culture of the peripheral blood cells. CD31, characteristically expressed in endothelial cells, was negative in the cultured cells.Conclusion:  Supplementation of peripheral blood CD34‐positive stem cells with body cavity fluid in vitro enhanced their differentiation toward cells of an epithelial or mesothelial phenotype, concomitant with loss of immunoreactivity for CD34. It is assumed that the routine cytological observation of cells obtained from body cavity fluid might cause possible cytomorphological and immunophenotypical changes due to the action of the growth factors contained in the body cavity fluid.
Intraperitoneal free cancer cells in non‐gynaecological adenocarcinomas: a reproducibility study
Authors: Piaton E. , Villeneuve L. , Maurice C. , Paulin C. , Cottier M. , Fontanière B. , Salle M. , Seigneurin D. , Vancina S. , Decullier E. , Gilly F. N. , Cotte E. 
Published: July 2011

E. Piaton, L. Villeneuve, C. Maurice, C. Paulin, M. Cottier, B. Fontanière, M. Salle, D. Seigneurin, S. Vancina, E. Decullier, F. N. Gilly and E. CotteIntraperitoneal free cancer cells in non‐gynaecological adenocarcinomas: a reproducibility studyObjective:  In recent years, therapeutic approaches including cytoreductive surgery followed by intraperitoneal chemotherapy have proven effective in peritoneal carcinomatosis of colorectal origin. If cytology is to be used to include patients in aggressive treatment regimens, it is necessary to evaluate its performance, particularly in terms of specificity. The aim of this study was to assess interobserver agreement for the detection of intraperitoneal free cancer cells (IFCCs) in patients with non‐gynaecological adenocarcinomas.Methods:  Over a 5‐year period, 1223 patients were recruited in 19 French surgery departments. Peritoneal samples were examined in 14 dispersed pathology laboratories. Giemsa‐stained slides were sent to a control reader blind to the previous diagnosis. Discordant cases, concordant positive results and a random selection of negative concordant cases were reviewed by a panel of seven cytopathologists. The ‘final diagnosis’ was that of the consensus meetings but took into account locally‐processed slides.Results:  Gathering dubious cases with negative results, a 95.6% concordance was achieved between local readers and the control reader. IFCCs were ascertained by the panel in 85 cases (7.0%). Eight of 873 colorectal cancers cases viewed locally were falsely positive (0.9%). Radiotherapy and neoadjuvant therapy had no impact on the false‐positive rate as assessed by final validation by the panel (P > 0.05). Samples initially considered as dubious were reclassified as negative by the panel in 24 of 25 cases (96.0%).Conclusions:  The panel consensus allowed reclassification of most dubious/equivocal peritoneal cytology cases, whereas clearcut distinction between benign and malignant cases was correctly achieved in almost all cases.
Analytical approximations of bulk and shear moduli for dry rock based on the differential effective medium theory
Authors: Li Hongbing , Zhang Jiajia 
Published: July 2011

ABSTRACTDifferential effective medium theory has been applied to determine the elastic properties of porous media. The ordinary differential equations for bulk and shear moduli are coupled and it is more difficult to obtain accurate analytical formulae about the moduli of dry porous rock. In this paper, in order to decouple these equations we first substitute an analytical approximation for the dry‐rock modulus ratio into the differential equation and derive analytical solutions of the bulk and shear moduli for dry rock with three specific pore shapes: spherical pores, needle‐shaped pores and penny‐shaped cracks. Then, the validity of the analytical approximations is tested by integrating the full differential effective medium equation numerically. The analytical formulae give good estimates of the numerical results over the whole porosity range for the cases of the three given pore shapes. These analytical formulae can be further simplified under the assumption of small porosity. The simplified formulae for spherical pores are the same as Mackenzie's equations. The analytical formulae are relatively easy to analyse the relationship between the elastic moduli and porosity or pore shapes and can be used to invert some rock parameters such as porosity or pore aspect ratio. The predictions of the analytical formulae for experimental data show that the formulae for penny‐shaped cracks are suitable to estimate the elastic properties of micro‐crack rock such as granite, they can be used to estimate the crack aspect ratio while the crack porosity is known and also to estimate the crack porosity evolution with pressure if the crack aspect ratio is given.
Changes in nursing practice: associations with responses to and coping with errors
Authors: Karga Mary , Kiekkas Panagiotis , Aretha Diamanto , Lemonidou Chrisoula 
Published: July 2011

Aims and objective.  To investigate emotional responses of nurses and perceived senior staff responses to errors, error‐coping strategies used by nurses and how these are associated with constructive or defensive changes in nursing practice.Background.  Healthcare professionals have generally reported distressing emotional responses to errors and fear concerns about their consequences. However, errors can also be part of a developmental process, by offering opportunities for learning and leading to constructive changes in clinical practice.Design.  Prospective, correlational, multicentre study.Methods.  Five hundred and thirty‐six structured questionnaires completed from nurses employed in various hospital departments were considered eligible for data extraction. The revised questionnaire used was evaluated for content validity.Results.  Data analysis indicated that positive perceived senior staff responses (p = 0·030), accepting error responsibility (p = 0·031) and seeking social support (p = 0·019) predicted constructive changes in nursing practice, while negative perceived senior staff responses (p = 0·040) and error escape‐avoidance (p = 0·041) predicted defensive changes.Conclusions.  Errors promote constructive changes in clinical practice when nurses are encouraged to use adaptive error‐coping strategies within a supportive, non‐blaming culture.Relevance to clinical practice.  These findings highlight the role of senior staff in the establishment of a supportive, trustful ward climate, so that nurses can learn from errors, prevent their recurrence and improve patient safety.
The dgt gene of Escherichia coli facilitates thymine utilization in thymine‐requiring strains
Authors: Itsko Mark , Schaaper Roel M. 
Published: July 2011

SummaryThe Escherichia coli dGTP triphosphohydrolase (dGTPase) encoded by the dgt gene catalyses the hydrolysis of dGTP to deoxyguanosine and triphosphate. The recent discovery of a mutator effect associated with deletion of dgt indicated participation of the triphosphohydrolase in preventing mutagenesis. Here, we have investigated the possible involvement of dgt in facilitating thymine utilization through its ability to provide intracellular deoxyguanosine, which is readily converted by the DeoD phosphorylase to deoxyribose‐1‐phosphate, the critical intermediate that enables uptake and utilization of thymine. Indeed, we observed that the minimal amount of thymine required for growth of thymine‐requiring (thyA) strains decreased with increased expression level of the dgt gene. As expected, this dgt‐mediated effect was dependent on the DeoD purine nucleoside phosphorylase. We also observed that thyA strains experience growth difficulties upon nutritional shift‐up and that the dgt gene facilitates adaptation to the new growth conditions. Blockage of the alternative yjjG (dUMP phosphatase) pathway for deoxyribose‐1‐phosphate generation greatly exacerbated the severity of thymine starvation in enriched media, and under these conditions the dgt pathway becomes crucial in protecting the cells against thymineless death. Overall, our results suggest that the dgt‐dependent pathway for deoxyribose‐1‐phosphate generation may operate under various cell conditions to provide deoxyribosyl donors.
Therapeutic drug monitoring is essential for intravenous busulfan therapy in pediatric hematopoietic stem cell recipients
Authors: Malär Reta , Sjöö Fredrik , Rentsch Katharina , Hassan Moustapha , Güngör Tayfun 
Published: July 2011

Malär R, Sjöö F, Rentsch K, Hassan M, Güngör T. Therapeutic drug monitoring is essential for intravenous busulfan therapy in pediatric hematopoietic stem cell recipients. Pediatr Transplantation 2011: 15: 580–588. © 2011 John Wiley & Sons A/S.Abstract:  Busulfan is widely used for myeloablative conditioning in HSCT. Intravenous busulfan has been introduced to reduce interindividual variability in plasma levels especially in pediatric patients. TDM of intravenous busulfan was performed in 34 pediatric HSCT patients with malignant (n = 9) and non‐malignant (n = 25) diseases (50% of patients <three yr) in a single‐center analysis (2006–2009). Intravenous busulfan was administered twice daily in a four‐h infusion according to recommended weight‐based doses. Busulfan drug levels were measured, and pharmacokinetic analysis was performed. The targeted busulfan exposure was aimed to range between AUC of 9000–12 000 ng/mL/h. In 23/34 patients (68%), the busulfan dose had to be adjusted at least once. In 16/23 patients (70%), the dose had to be increased in a range of 7 to 33%, while in 7/23 patients (30%), the dose had to be decreased by 7–20%. The need of dose adjustment was not related to weight, age, or underlying disease. Seven out of 34 patients (21%) <20 months experienced VOD despite that their total AUCs were within the target AUC. TDM of intravenous busulfan is essential to increase the efficacy and safety of busulfan‐based conditioning protocols in pediatric HSCT recipients.
Genetic resistance to Hymenoscyphus pseudoalbidus limits fungal growth and symptom occurrence in Fraxinus excelsior
Authors: McKinney L. V. , Thomsen I. M. , Kjær E. D. , Nielsen L. R. 
Published: July 2011

SummaryThe European common ash (Fraxinus excelsior) is currently threatened by a pathogenic fungus, Hymenoscyphus pseudoalbidus, which seems to enter the trees through the leaves. Continuous assessments of 39 clones in Danish field trials have shown that there are significant differences in the susceptibility of clones to the new disease. Interestingly, clones that showed early leaf senescence in the autumn were in general less susceptible to the disease than late‐senescing clones. Thus, variation in susceptibility could be owing to phenological differences associated with the infection biology. To test whether differences in susceptibility are driven by genetically based factors other than phenology, we compared inoculations with H. pseudoalbidus on four highly susceptible clones with those of four less susceptible clones. Development of necrosis was hereafter followed regularly. The growth of the fungus in the inner bark was further detected with species‐specific PCR primers. The severity of the response to infection shows significant differentiation among clones and significant correlation with clone susceptibility, as assessed from natural infections in field trials. The fungus was detected in tissues immediately surrounding the necrosis but showed some signs of endophytic growth. The results suggest that healthier clones are able to limit the growth and spread of the fungus and thereby minimize the occurrence of symptoms. This gives hope for the future preservation of F. excelsior in Europe through selection and breeding.
Alternative air vehicles for sterile insect technique aerial release
Authors: Tan L. T. , Tan K. H. 
Published: July 2011

AbstractThe majority of current sterile insect technique (SIT) programmes release chilled adult sterile insects into the wild by means of small fixed‐wing aircraft or occasionally helicopters. Besides being the fastest method of release, it has been demonstrated to provide uniform distribution over target areas and to help ensure sterile insect quality and survivability. It is, however, also the most expensive method of release, and on average, current aerial release contracts constitute about 40% of the annual operating budget of sterile fly emergence and release centres. This is mainly due to the fact that the aircraft used are highly over‐specified relative to the requirements of small to medium SIT aerial release programmes. Furthermore, this stage of the SIT process has traditionally been neglected, while research and process optimization efforts have focused mainly on the mass rearing and sterilization of insects. This study addresses this gap by presenting an extensive survey of other forms of aerial transport, of which five alternative types of aerial vehicles are identified as having the potential to make significant cost savings compared with the current aircraft of SIT programmes. These different alternatives were further evaluated against the requirements of current SIT programmes and also compared in terms of cost. Of these, two fulfilled all requirements, but given that an unmanned aircraft could bring even more cost savings, we present two further proposals for unmanned vehicles, the first a custom‐built fixed‐wing unmanned aerial vehicle or long‐range radio‐controlled aircraft and the second an unmanned dirigible, which is easier to control remotely in view of its natural tendency to stay airborne. Both these alternative aircraft proposals present major cost savings in terms of pilot wages, maintenance and fuel consumption, with the largest cost saving made by eliminating the need for a pilot, as the take‐off weight is the largest source of fuel consumption. Considering that current aerial release contracts represent a significant proportion of the operating budget of SIT programmes, the financial savings of implementing either of these options will have a significant impact on the financial attractiveness of the overall SIT process. Cheaper alternatives to currently used aircraft will also allow smaller SIT programmes to use aerial release methods, thereby widening applicability of aerial release methods.
The best time of day to monitor and manipulate weaver ant colonies in biological control
Authors: Peng R. , Christian K. , Gibb K. 
Published: July 2011

AbstractThe weaver ant, Oecophylla smaragdina (Hymenoptera: Formicidae), is a successful predator and repellent of a range of insect pests of many economically important crops and forest trees. To use the ant as a biocontrol agent, extension officers and farmers need to know the best time of day to identify and transplant the ant colonies and to measure the abundance of the ant. To answer these questions, it is important to know about ant activity over a 24‐h period at the colony level. Ant activities of three weaver ant colonies on the Tiwi campus of Charles Darwin University, Darwin, were measured in both dry and wet seasons in 1997 and 1998. The activity patterns on three types of ant trails showed that ants were least active between the hours of 10:30 and 14:00, and their activity peaked between 16:00 and 21:00 h. There was also a smaller activity peak from 8:00 to 9:00 h. The best time of day to identify ant colonies and to measure ant abundance is from 16:00 to 21:00 h (late afternoon to dusk). The best time to transplant weaver ant colonies is between 10:30 and 14:00 h (midday).