bluuebunny/crossref_metadata_2025 huggingface dataset:
Current Status of Pylorus‐Preserving Gastrectomy for the Treatment of Gastric Cancer: A Questionnaire Survey and Review of Literatures
Authors: Shibata Chikashi , Saijo Fumito , Kakyo Masayuki , Kinouchi Makoto , Tanaka Naoki , Sasaki Iwao , Aikou Takashi ,   The Society for the Study of Postoperative Morbidity After Gastrectomy
Published: February 2012

Purpose

This study was designed to investigate the current status of pylorus‐preserving gastrectomy (PPG) for the treatment of gastric cancer by sending a questionnaire to institutions in Japan.

Methods

The questionnaire was prepared and sent to 930 institutions approved by the Japanese Society of Gastroenterological Surgery. Questions were the indications for PPG, preservation of the vagus nerves and the infra‐pyloric artery, whether suprapyloric lymph nodes are dissected, distance between the pylorus and the gastrogastrostomy, and the advantages and disadvantages of PPG.

Results

Responses were obtained from 345 institutions (37.1%). In 148 institutions, PPG was included in the choices of operations for gastric cancer and indicated for patients with tumors no deeper than the submucosal layer for differentiated‐type carcinoma, or for tumors limited to the mucosa even in poorly differentiated types in 105 institutions. The vagus was preserved in 73.5%, the infrapyloric artery was preserved in 49.4%, and the dissection of suprapyloric lymph nodes were partly performed in 56.2%. The distance between gastrogastrostomy and the pyloric ring was 3–3.9 cm in 43.4% and 2–2.9 cm in 39%. Layer‐to‐layer anastomosis was the most representative technique for gastrogastrostomy. The advantages of PPG with decreased incidence of dumping syndrome and remnant gastritis were quoted in 130 and 82 institutions, respectively. Delayed gastric emptying was considered as the most frequent disadvantage of PPG, as quoted by 111 institutions.

Conclusions

These results indicate that standard technique in PPG includes the preservation of the vagus and infrapyloric artery, in part dissection of suprapyloric lymph nodes, and layer‐to‐layer anastomosis for reconstruction. The optimal length of the antral cuff is still controversial.
Aurora kinase inhibitors: Progress towards the clinic
Authors: Kollareddy Madhu , Zheleva Daniella , Dzubak Petr , Brahmkshatriya Pathik Subhashchandra , Lepsik Martin , Hajduch Marian
Published: February 2012

The Aurora kinases (serine/threonine kinases) were discovered in 1995 during studies of mutant alleles associated with abnormal spindle pole formation inDrosophila melanogaster.They soon became the focus of much attention because of their importance in human biology and association with cancer. Aurora kinases are essential for cell division and are primarily active during mitosis. Following their identification as potential targets for cancer chemotherapy, many Aurora kinase inhibitors have been discovered, and are currently under development. The binding modes of Aurora kinase inhibitors to Aurora kinases share specific hydrogen bonds between the inhibitor core and the back bone of the kinase hinge region, while others parts of the molecules may point to different parts of the active site via noncovalent interactions. Currently there are about 30 Aurora kinase inhibitors in different stages of pre-clinical and clinical development. This review summarizes the characteristics and status of Aurora kinase inhibitors in preclinical, Phase I, and Phase II clinical studies, with particular emphasis on the mechanisms of action and resistance to these promising anticancer agents. We also discuss the validity of Aurora kinases as oncology targets, on/off-target toxicities, and other important aspects of overall clinical performance and future of Aurora kinase inhibitors.
Ovariectomy in the developing rat decelerates cortical spreading depression in adult brain
Authors: Accioly Noranege Epifânio , Benevides Regina de Deus Lira , Costa Belmira Lara da Silveira Andrade da , Guedes Rubem Carlos Araujo
Published: February 2012

The brain of mammals is one important target organ for the action of gonadal steroids and, when occurring during development, this hormonal influence may result in important repercussion on the brain electrophysiological properties at adulthood, some of which depending on the brain excitability. Here we have characterized in early‐ovariectomized adult rats the brain ability to propagate the excitability‐related phenomenon known as cortical spreading depression (CSD), as an index of the cerebral electrophysiological effects of the early‐induced absence of the ovarian hormones. Wistar female rat pups (7‐day old) underwent bilateral ovariectomy (Ovx group; n = 21) or Sham surgery (Sham group; n = 22), or no surgery (Naive group; n = 22). When the pups became adult (90–130 days), they were submitted to the recording of CSD (electrocorticogram and slow DC‐voltage variation) in two points of the cortical surface during 4 h. Compared with both Naïve and Sham controls, bilateral ovariectomy early in life resulted in significantly higher body weights (from days 50–65 onwards) and severely reduced uterus weights at adulthood. Furthermore, in the Ovx animals the amplitudes and durations of the DC‐potential changes of CSD were higher, and the CSD propagation velocities were reduced. Another group of rats ovariectomized in adulthood did not present such CSD alterations. It is concluded that ovariectomy during brain development is causally associated with the CSD changes in the adult brain, indicating a long‐lasting effect, which we suggest as being related to the long‐term suppression of the action of the ovarian hormones on brain excitability.
Showers, Sweating and Suing: Legionnaires’ Disease and ‘New’ Infections in Britain, 1977–90
Authors: MacFarlane John T. , Worboys Michael
Published: February 2012

Legionnaires’ disease is now routinely discussed as an ‘emerging infectious disease’ (EID) and is said to be one of the earliest such diseases to be recognised. It first appeared in 1976 and its cause was identified in 1977, the same year that Ebola fever, Hantaan virus and Campylobacter jejuni arrived. The designation of Legionnaires’ disease as an EID was retrospective; it was not and could not be otherwise as the category only gained currency in the early 1990s. In this article we reflect on the changing medical understanding and social profile of Legionnaires’ disease in the decade or so from its recognition to the creation of EIDs, especially its ambivalent position between public health and clinical medicine. However, we question any simple opposition, between public health experts who approached Legionnaires’ disease as a new and worrying environmental threat that could be prevented, and clinicians who saw it as another cause of pneumonia that could be managed by improved diagnosis and treatment. We argue that in the British context of public spending cuts and the reform of public health, the category of ‘new’ diseases, in which Legionnaires’ disease was central, was mobilised ahead of the EID lobby of the early 1990s, by interested groups in medicine to defend infectious diseases services.
Benthamite Radicalism and its Scots Presbyterian Contexts
Authors: WALLACE VALERIE
Published: February 2012

This article argues that James Mill's immersion in Presbyterianism inspired an aversion to hierarchical government and a bias in favour of the Church of Scotland. These views are discernible in Bentham'sChurch-of-Englandism. Bentham argued for disestablishment on principle but, praising the Scottish Church as a ‘model of perfection’, omitted the Kirk from his church reform manifesto. His position on disestablishment, however, and his endorsement of Presbyterianism were aligned with a voluntaryist strain of Presbyterian ecclesiological theory; Presbyterian dissenters and Benthamite Radicals began to protest against the Kirk's established status. Underpinned significantly by Presbyterian tradition and laced with Benthamic influence, a radical voluntary campaign emerged in Scotland which sought to dismantle the old order and usher in a new era of political democracy and religious voluntaryism. Radicalism in Scotland was not solely characterized by the ‘programmatic atheism’ which J. C. D. Clark believes defined Benthamite ideology; Benthamism, it transpires, was not straightforwardly secularist.
Operationalising salience: definite article reduction in the North of England
Authors: RÁCZ PÉTER
Published: February 2012

Definite article reduction (DAR) is a dialectal variable confined to the North of England. In DAR dialects, the standard article alternates with a reduced one, which is mostly realised as a glottal stop and sometimes as a voiceless fricative before vowels. DAR is a salient sociolinguistic marker in the sense of Labov (1972) and Trudgill (1986). This article argues that its salience is derived from its status as a good boundary marker that listeners can utilise in order to segment the speech stream.

Salience is the property of a variable which makes it cognitively or perceptually prominent both for speakers of the dialect and for speakers of other dialects. DAR is a salient marker inasmuch as it shows variation and style shifting, can be an identity marker, and has long been recognised by layperson and linguist alike as a typical feature of Northern speech.

It will be argued that DAR is salient since it is a good word-boundary marker. The reduced article constitutes domains of low transitional probability, which listeners exploit to segment the speech signal. It has been recognised that word segmentation plays a major role in speech processing and that listeners use statistical inferences (besides other kinds of information) to locate word boundaries. The conclusion is that the salience of DAR can be derived from its distributions, as these distributions result in the variable's perceptual prominence.
Exploring the relation between the qualitative and quantitative uses of the determiner some
Authors: DUFFLEY PATRICK J. , LARRIVÉE PIERRE
Published: February 2012

This article attempts to repair the neglect of the qualitative uses of some and to suggest an explanation which could cover the full range of usage with this determiner – both quantitative and qualitative – showing how a single underlying meaning, modulated by contextual and pragmatic factors, can give rise to the wide variety of messages expressed by some in actual usage. Both the treatment of some as an existential quantifier and the scalar model which views some as evoking a less-than-expected quantity on a pragmatic scale are shown to be incapable of handling the qualitative uses of this determiner. An original analysis of some and the interaction of its meaning with the defining features of the qualitative uses is proposed, extending the discussion as well to the role of focus and the adverbial modifier quite. The crucial semantic feature of some for the explanation of its capacity to express qualitative readings is argued to be non-identification of a referent assumed to be particular. Under the appropriate conditions, this notion can give rise to qualitative denigration (implying it is not even worth the bother to identify the referent) or qualitative appreciation (implying the referent to be so outstanding that it defies identification). The explanation put forward is also shown to cover some's use as an approximator, thereby enhancing its plausibility even further.
Relationship of frontal D2/3 binding potentials to cognition: a study of antipsychotic-naive schizophrenia patients
Authors: Fagerlund Birgitte , Pinborg Lars H. , Mortensen Erik Lykke , Friberg Lars , Baaré William F. C. , Gade Anders , Svarer Claus , Glenthøj Birte Y.
Published: February 2012

Studies of in vivo dopamine receptors in schizophrenia have mostly focused on D2 receptors in striatal areas or on D1 receptors in cortex. No previous study has examined the correlation between cortical dopamine D2/3 receptor binding potentials and cognition in schizophrenia patients. The objective was to examine this relation in the frontal cortex in first-episode, drug-naive schizophrenia patients. Based on preclinical and pharmacological evidence, we specifically expected to find a relation between D2/3 receptor binding potentials and set shifting. This was a cross-sectional, case-control study using single-photon emission computerized tomography with the D2/3-receptor ligand [123I]epidepride, co-registered with structural magnetic resonance imaging and correlated to cognitive measures. Participants were 24 antipsychotic-naive, first-episode schizophrenia patients and 20 healthy controls matched for gender and age. For patients, a significant linear correlation between D2/3 BPND and set shifting was found, while significant quadratic associations were observed for verbal fluency, planning and attention. For controls, the only significant association with D2/3 BPND was a quadratic partial correlation for set shifting. The main findings indicated a relation between D2/3 receptor binding in the frontal cortex and set shifting, planning and attention, but also support a differential involvement of cortical dopamine D2/3 receptor binding in at least some cognitive functions, perhaps particularly attention, in schizophrenia patients compared to healthy people. The results suggest that cortical D2/3 receptor function may be more involved in some cognitive functions (i.e. attention, fluency and planning) in patients with schizophrenia than in healthy people, suggesting that information processing in schizophrenia may be characterized by lower signal:noise ratios.
Wenn Therapien vorzeitig scheitern
Authors: Cinkaya Fatima , Schindler Amrei , Hiller Wolfgang
Published: February 2012

Zusammenfassung. Theoretischer Hintergrund: Zu Abbrüchen ambulanter Psychotherapien fehlen gesicherte Erkenntnisse über Häufigkeit, Auftretensmerkmale und Risikofaktoren. Fragestellung: Diese Studie untersucht soziodemografische und klinische Merkmale von Abbrechern im Routinebetrieb einer verhaltenstherapeutischen Hochschulambulanz. Methode: Wir klassifizierten 1391 konsekutive Patienten als Completer sowie qualitätsrelevante und qualitätsneutrale Abbrecher. Ergebnisse: Die Gesamtabbruchrate lag bei 24,6% und 14,1% der Abbrüche waren qualitätsrelevant. 56,1% erfolgten innerhalb der ersten 20 Sitzungen. Häufigster Grund war mit 28,1% eine unzureichende Veränderungsmotivation. Am häufigsten brachen Patienten mit Borderline-Persönlichkeitsstörungen (30,2%) und anderen Persönlichkeitsstörungen (25,0%) ab. Weitere Prädiktoren waren erhöhte Psychopathologie (r = 0,18), geringe Therapiemotivation (r = –0,15) und geringe Erfolgserwartung (r = 0,13). Die Vorhersagekraft aller Variablen war jedoch klein. Diskussion: Für Therapieabbrüche ließen sich in dieser naturalistischen Stichprobe zwar einige Risikofaktoren identifizieren, deren Vorhersagekraft jedoch aufgrund kleiner Effektstärken nicht überschätzt werden sollte. Die Suche nach weiteren und bedeutsameren Risikofaktoren sollte weitergehen.
Protective Factors and Suicidality in Members of Arab Kindred
Authors: Hamdan Sami , Melhem Nadine , Orbach Israel , Farbstein Ilana , El-Haib Mohammad , Apter Alan , Brent David
Published: February 2012

Background: Relatively little is known about the role of protective factors in an Arab population in the presence of suicidal risk factors. Aims: To examine the role of protective factors in a subsample of in large Arab Kindred participants in the presence of suicidal risk factors. Methods: We assessed protective and risk factors in a sample of 64 participants (16 suicidal and 48 nonsuicidal) between 15 and 55 years of age, using a comprehensive structured psychiatric interview, the Composite International Diagnostic Interview (CIDI), self-reported depression, anxiety, hopelessness, impulsivity, hostility, and suicidal behavior in first-degree and second-relatives. We also used the Religiosity Questionnaire and suicide attitude (SUIATT) and multidimensional perceived support scale. Results: Suicidal as opposed to nonsuicidal participants were more likely to have a lifetime history of major depressive disorder (MDD) (68.8% vs. 22.9% χ2= 11.17, p = .001), an anxiety disorder (87.5% vs. 22.9, χ2= 21.02, p < .001), or posttraumatic stress disorder (PTSD) (25% vs. 0.0%, Fisher’s, p = .003). Individuals who are otherwise at high risk for suicidality have a much lower risk when they experience higher perceived social support (3.31 ± 1.36 vs. 4.96 ± 1.40, t = 4.10, df = 62, p < .001), and they have the view that suicide is somehow unacceptable (1.83 ± .10 vs. 1.89 ± .07, t = 2.76, df = 60, p = .008). Conclusions: Taken together with other studies, these data suggest that the augmentation of protective factors could play a very important role in the prevention of incidental and recurrent suicidal behavior in Arab populations, where suicidal behavior in increasing rapidly.
Thwarted Belongingness and Perceived Burdensomeness in Suicide Notes
Authors: Gunn John F. , Lester David , Haines Janet , Williams Christopher L.
Published: February 2012

Background: Joiner’s interpersonal theory of suicide postulates that suicide occurs because of thwarted belongingness and perceived burdensomeness, combined with a capability for committing suicide. Aims: The present study examines the frequency of the presence of the themes of thwarted belongingness and perceived burdensomeness in suicide notes. Methods: A total of 261 suicide notes from 1091 consecutive completed suicides in Tasmania were rated for the presence of thwarted belongingness and perceived burdensomeness. Results: Contrary to the theory, few suicide notes were found to include perceived burdensomeness (10.3%) and thwarted belongingness (30.7%), and only 4.2% had both themes. The notes of women more often contained the theme of perceived burdensomeness, while the notes of younger suicides more often contained the theme of thwarted belongingness. Conclusions: Joiner’s theory of suicide may apply to only a small percentage of suicides who leave suicide notes.
Developing a Psychophysical Measure to Assess Duration Discrimination in the Millisecond Range
Authors: Rammsayer Thomas H.
Published: February 2012

Duration discrimination in the range of milliseconds is essential for various aspects of behavior and individual differences. The present paper addresses important methodological issues, such as type of stimuli, type of task, method for threshold estimation, and temporal sensitivity of the psychophysical procedure, that should be borne in mind when developing a sensitive and reliable duration discrimination task. Furthermore, it introduces a psychophysical approach for the assessment of individual differences in duration discrimination of extremely brief intervals in the subsecond range. Monte Carlo simulations provide clear evidence that this task is sensitive enough to correctly detect a true difference between temporal stimuli as small as 2 ms with a high probability. Further, the distributional properties of individual performance scores obtained from 534 participants by means of the introduced duration discrimination task are presented.
Perceptual Underconfidence
Authors: Stankov Lazar , Pallier Gerry , Danthiir Vanessa , Morony Suzanne
Published: February 2012

Experimental interest in human decision making has been fertile in the past two decades. It is generally recognized that answers to questions involving general knowledge tend to produce overconfidence, whereas responses to perceptual tasks often result in underconfidence. While experimental psychologists debated the relative merits of single or dual explanations of these phenomena, differential psychologists suggested that confidence is a trait: Some people have high confidence and others express the opposite, no matter what type of task is undertaken. The current study examined these different perspectives using two complex cognitive and nine perceptual discrimination tasks from different sensory modalities. Findings suggest that underconfidence does not generalize across the perceptual domain, indicating that a more complex account of the miscalibration effect is needed. Such an account should incorporate both task characteristics and individual differences to produce a satisfactory psychological explanation of miscalibration. This point is highlighted by the presence of a strong confidence factor that has loadings from confidence ratings from diverse perceptual and cognitive tasks employed in this study.
Combining Cognitive and Personality Measures of Impulse Control in the Assessment of Childhood ADHD
Authors: Rauch Wolfgang A. , Gold Andreas , Schmitt Kathrin
Published: February 2012

Impulse control is measured both with personality questionnaires and in cognitive laboratory tasks, yet previous results concerning the convergence of these two types of instruments are inconsistent. The current study measured impulse control of children with and without ADHD with a personality questionnaire and a go/no-go task as well as with parent ratings of ADHD symptomatology. Scores on the two measures correlate weakly with one another, yet both correlate moderately to strongly with parent ratings – and both explain unique variance of parent ratings. Accordingly, the simple sum of the standardized scores from the two measures outperforms the single measures in diagnostic accuracy and association with ADHD symptomatology. Results show that a conjoint application of personality and cognitive measures of impulse control is useful for an extended assessment of ADHD. The adequacy of personality and cognitive measures for assessing distinct facets of impulse control is discussed with regard to theoretical models of impulsivity and with regard to ADHD symptomatology.
A comparison of methods for a priori bias correction in soil moisture data assimilation
Authors: Kumar Sujay V. , Reichle Rolf H. , Harrison Kenneth W. , Peters‐Lidard Christa D. , Yatheendradas Soni , Santanello Joseph A.
Published: February 2012

Data assimilation is increasingly being used to merge remotely sensed land surface variables such as soil moisture, snow, and skin temperature with estimates from land models. Its success, however, depends on unbiased model predictions and unbiased observations. Here a suite of continental‐scale, synthetic soil moisture assimilation experiments is used to compare two approaches that address typical biases in soil moisture prior to data assimilation: (1) parameter estimation to calibrate the land model to the climatology of the soil moisture observations and (2) scaling of the observations to the model's soil moisture climatology. To enable this research, an optimization infrastructure was added to the NASA Land Information System (LIS) that includes gradient‐based optimization methods and global, heuristic search algorithms. The land model calibration eliminates the bias but does not necessarily result in more realistic model parameters. Nevertheless, the experiments confirm that model calibration yields assimilation estimates of surface and root zone soil moisture that are as skillful as those obtained through scaling of the observations to the model's climatology. Analysis of innovation diagnostics underlines the importance of addressing bias in soil moisture assimilation and confirms that both approaches adequately address the issue.
Discretizing a discrete fracture model for simulation of radial transport
Authors: Kozuskanich John C. , Novakowski Kent S. , Anderson Bruce C.
Published: February 2012

In this study we examine the required spatiotemporal discretization for numerical simulation of field‐scale radial solute transport using a discrete fracture model. Point‐to‐point and borehole‐to‐point scenarios considering a single fracture, hydrodynamic dispersion, and matrix diffusion were modeled in two‐dimensional (2‐D) and three‐dimensional (3‐D) domains, and were verified using existing semianalytical solutions. The results clearly show the need for accurate spatiotemporal discretization in numerical simulations of this type. Spatial discretization away from the injection point/well in the horizontal plane was found to be more demanding than away from the fracture in the vertical direction. Concentration control, which was used in the time step discretization of the transport solution, varied over two orders of magnitude depending on the scenario being modeled. The fine spatiotemporal discretization required may significantly limit the ability to simulate radial transport in more complex hydrogeological conditions (i.e., multiple fractures and injection points/wells) particularly in 3‐D because of long computational runtimes.
A note on trapped Gerstner waves
Authors: Weber Jan Erik H.
Published: February 2012

The progressive Gerstner wave is studied theoretically in a rotating inviscid ocean when the bottom has a constant slope. Exact solutions are found in Lagrangian coordinates without applying the hydrostatic assumption for the pressure. For waves propagating with the coast to the right in the Northern Hemisphere, trapped Gerstner wave solutions are found for slope angles β with respect to the horizontal in the range 0 < β ≤ π/2. In particular, the Stokes edge wave transforms into the deep‐water coastal Kelvin wave in the vertical wall limit β = π/2. It is shown that standing waves obtained by superposition of oppositely traveling Gerstner wave trains in the nonrotating case are not exact solutions of the Lagrangian equations. This is discussed in relation to observed beach features and runup patterns.
Assessments of cloud liquid water contributions to GPS radio occultation refractivity using measurements from COSMIC and CloudSat
Authors: Yang S. , Zou X.
Published: February 2012

Global cloud parameters including cloud liquid water, cloud base height, cloud top height, and cloud type are observed from the cloud profiling radar onboard CloudSat. Global Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) radio occultation (RO) data during a 3 year period from 2007 to 2009 are collocated in space and time with CloudSat data. The collocated data set is then classified into seven groups: one clear‐sky condition and six different cloud types with liquid water content (LWC) measurements. For each group, atmospheric refractivity, temperature, and water vapor derived from COSMIC GPS ROs are compared with those of the European Centre for Medium‐Range Weather Forecasts (ECMWF) analyses. It is found that the COSMIC GPS RO refractivity observations are systematically greater than the refractivity calculated from ECMWF analyses, which is to be referred as a positive N bias in clouds. The fractional N bias is as high as 1.2% depending on cloud types. Using CloudSat LWC, it is demonstrated that LWC can contribute 0.8% of the total refractivity by individual clouds and 0.16% of the positive N bias. The 0.16% positive N bias is comparable in magnitude to the retrieval uncertainty quantified by the mean difference (ΔNO‐R) between the observed refractivity with LWC contribution subtracted and the refractivity calculated using GPS retrieved profiles of temperature, pressure, and humidity. The values of ΔNO‐R increase linearly with LWC as anticipated theoretically. Positive N biases are spatially correlated with positive water vapor biases, negative temperature biases, and large liquid water contents.
Effect of oxidized LDL on the expression of connexins in cultured human umbilical‐vein endothelial cells
Authors: Zhang Shunrong , Hong Mingming , Gao Yue
Published: February 2012

The role of connexins in atherogenesis has attracted increasing attention in recent years; however, whether oxidized LDL (low density lipoprotein) is one of the pro‐atherosclerotic factors that can influence the expression of endothelial connexins remains unclear. To investigate the effect of oxidized LDL on the gene expression of the gap junction proteins connexin37, connexin40 and connexin43 in cultured HUVEC (human umbilical‐vein endothelial cells) in vitro, HUVEC were cultured and divided into groups before being stimulated with various concentrations of oxidized LDL for different times. mRNA expression of connexin37, connexin40 and connexin43 in each group were determined semi‐quantitatively by RT—PCR (reverse transcription—PCR), while protein expression of the three connexins was investigated by immunocytochemical staining. Various concentrations of oxidized LDL down‐regulated mRNA and protein expression of connexin37, and up‐regulated the expression of connexin40 and connexin43. Time‐dependent dynamic alterations of the mRNA expression levels of connexin37, connexin40 and connexin43 were also found in HUVEC stimulated by oxidized LDL. We conclude that oxidized LDL can change the expression of connexin genes in cultured HUVEC within a short period, and thus may be involved in the pro‐atherosclerotic effect of oxidized LDL.
Human umbilical cord blood‐derived mesenchymal stem cells (hUCB‐MSC) inhibit the proliferation of K562 (human erythromyeloblastoid leukaemic cell line)
Authors: Fonseka Malini , Ramasamy Rajesh , Tan Boon Chong , Seow Heng Fong
Published: February 2012

hUCB‐MSC (human umbilical cord blood‐derived mesenchymal stem cells) offer an attractive alternative to bone marrow‐derived MSC for cell‐based therapy by being less invasive a source of biological material. We have evaluated the effect of hUCB‐MSC on the proliferation of K562 (an erythromyeloblastoid cell line) and the cytokine secretion pattern of hUCB‐MSC. Co‐culturing of hUCB‐MSC and K562 resulted in inhibition of proliferation of K562 in a dose‐dependent manner. However, the anti‐proliferative effect was reduced in transwells, suggesting the importance of direct cell‐to‐cell contact. hUCB‐MSC inhibited proliferation of K562, arresting them in the G0/G1 phase. NO (nitric oxide) was not involved in the hUCB‐MSC‐mediated tumour suppression. The presence of IL‐6 (interleukin 6) and IL‐8 were obvious in the hUCB‐MSC conditioned media, but no significant increase was found in 29 other cytokines. Th1 cytokines, IFNα (interferon α), Th2 cytokine IL‐4 and Th17 cytokine, IL‐17 were not secreted by hUCB‐MSC. There was an increase in the number of hUCB‐MSC expressing the latent membrane‐bound form of TGFβ1 co‐cultured with K562. The anti‐proliferative effect of hUCB‐MSC was due to arrest of the growth of K562 in the G0/G1 phase. The mechanisms underlying increased IL‐6 and IL‐8 secretion and LAP (latency‐associated peptide; TGFβ1) by hUCB‐MSC remains unknown.
Disorder regimes and equivalence of disorder types in artificial spin ice
Authors: Budrikis Zoe , Politi Paolo , Stamps R. L.
Published: February 2012

The field-induced dynamics of artificial spin ice are determined in part by interactions between magnetic islands and the switching characteristics of each island. Disorder in either of these affects the response to applied fields. Numerical simulations are used to show that disorder effects are determined primarily by the strength of disorder relative to inter-island interactions, rather than by the type of disorder. Weak and strong disorder regimes exist and can be defined in a quantitative way.
Exchange coupling in hard/soft-magnetic multilayer films with non-magnetic spacer layers
Authors: Cui W. B. , Liu W. , Gong W. J. , Liu X. H. , Guo S. , Yang F. , Wang Z. H. , Zhang Z. D.
Published: February 2012

The exchange coupling in textured HM/NM/α-Fe/NM/HM multilayer films (HM = NdFeB or PrFeB hard magnetic layers; NM = nonmagnetic Mo, Cu, and Cr layer) is shown to be indirect and long-range. The influences of thickness of NM spacer layer and HM layer, the material of HM phase and NM spacer layers, and the texture of HM layer, on the effective critical correlation length (Lexeff) and exchange-coupling between soft-magnetic (SM) and HM layers are investigated. A non-linear dependence of Lexeff on the thickness of NM spacer layer is observed. Magnetostatic interaction may lead to the observed non-linear dependence.
Characteristic and magnetic field analysis of a high temperature superconductor axial-flux coreless induction maglev motor
Authors: Wei Qin , Yu Fan , Jin Fang , Shuo Li , Guoguo Li , Gang Lv
Published: February 2012

A new high temperature superconductor axial-flux coreless maglev motor (HTS AFIM) is proposed, of which the primary windings are made of HTS tapes and the secondary is a non-magnetic conductor. The main works of this paper are the magnetic-field computation and characteristics analysis of HTS AFIM. For the first one, the reduction of magnetic fields near outer and inner radius of the HTS AFIM is solved by introducing the sub-loop electro-magnetic model along the radial position. For the second one, the AC losses of HTS coils are calculated. The relationships between the device’s characteristics and device parameters are presented, and the results indicate that under certain frequency and current levitation device can output enough lift force. The conclusions are verified by finite element calculations.
A study of the correlation between hydrogen content and magnetism in ZnCoO
Authors: Lee Seunghun , Kim Bum-Su , Seo Seung-Wan , Chan Cho Yong , Kyu Kim Sung , Pil Kim Jong , Jeong Il-Kyoung , Ryong Cho Chae , Uk Jung Chang , Koinuma Hideomi , Jeong Se-Young
Published: February 2012

Through the hydrogen treatment of Co-doped ZnO (ZnCoO), the Co-H-Co complex manifests the magnetization mediated by H. The increase in hydrogen content causes an increase in the number of Co-H-Co units, which can be controlled by the hydrogen treatment conditions. The 15 mol. % ZnCoO showed a proportional tendency between the hydrogen content and remnant magnetization under different conditions of rf power for the plasma treatment. The 20 mol. % sample showed deviation from the proportional tendency by the existing CoO phase before hydrogen injection and the formation of the Co metal phase after hydrogen injection. If one ensures the enhanced solubility limit of Co in ZnO and uses the correlation between the hydrogen content and magnetization below the solubility limit, this magnetic tool may be a good method for the measurement of the hydrogen content.
Control of magnetic and transport properties in Nd0.45Sr0.55MnO3 films through epitaxial strain
Authors: Meng H. , Zhang Y. Q. , Wang X. W. , Tang Y. L. , Wang Z. H. , Zhu Y. L. , Zheng Jian-Guo , Zhang Z. D.
Published: February 2012

The influence of epitaxial strain, tuned with tetragonal distortion c/a from 0.965 to 1.034 by choosing different substrates and varying film thickness, on the magnetic and transport properties of Nd0.45Sr0.55MnO3 thin films has been investigated. It is found that epitaxial strain, depending on the value of c/a, can enhance or decrease the stability of A-type AF to induce ferromagnetic fluctuation and C-type AF instead of A-type AF.
Plasma characterization of the superconducting proton linear accelerator plasma generator using a 2 MHz compensated Langmuir probe
Authors: Schmitzer C. , Kronberger M. , Lettry J. , Sanchez-Arias J. , Störi H.
Published: February 2012

The CERN study for a superconducting proton Linac (SPL) investigates the design of a pulsed 5 GeV Linac operating at 50 Hz. As a first step towards a future SPL H− volume ion source, a plasma generator capable of operating at Linac4 or nominal SPL settings has been developed and operated at a dedicated test stand. The hydrogen plasma is heated by an inductively coupled RF discharge e− and ions are confined by a magnetic multipole cusp field similar to the currently commissioned Linac4 H− ion source. Time-resolved measurements of the plasma potential, temperature, and electron energy distribution function obtained by means of a RF compensated Langmuir probe along the axis of the plasma generator are presented. The influence of the main tuning parameters, such as RF power and frequency and the timing scheme is discussed with the aim to correlate them to optimum H− ion beam parameters measured on an ion source test stand. The effects of hydrogen injection settings which allow operation at 50 Hz repetition rate are discussed.
Production of low-Z ions in the Dresden superconducting electron ion beam source for medical particle therapy
Authors: Zschornack G. , Schwan A. , Ullmann F. , Grossmann F. , Ovsyannikov V. P. , Ritter E.
Published: February 2012

We report on experiments with a new superconducting electron beam ion source (EBIS-SC), the Dresden EBIS-SC, with the objective to meet the main requirements for their application in particle-therapy facilities. Synchrotrons as well as innovative accelerator concepts, such as high-gradient linacs which are driven by a large-current cyclotron (CYCLINACS) and direct drive RF linear accelerators may benefit from the advantages of EBISs in regard to their functional principle. First experimental studies of the production of low-Z ions such as H+, \documentclass[12pt]{minimal}\begin{document}${\rm H}_{2}^{+}$\end{document}H2+, \documentclass[12pt]{minimal}\begin{document}${\rm H}_{3}^{+}$\end{document}H3+, C4+, and C6+ are presented. Particular attention is paid to the ion output, i.e., the number of ions per pulse and per second, respectively. Important beam parameters in this context are, among others, ion pulse shaping, pulse repetition rates, beam emittance, and ion energy spread.
Surface plasma source with anode layer plasma accelerator
Authors: Dudnikov Vadim
Published: February 2012

Proposed plasma generation system can be used for high current negative ion beam production and for directed deposition by flux of sputtered neutrals and negative ions. The main mechanism of negative ion formation in surface plasma sources is the secondary emission from low work function surface bombarded by a flux of positive ion or neutrals. The emission of negative ions is enhanced significantly by introducing a small amount of cesium or other substance with low ionization potential. In the proposed source are used positive ions generated by Hall drift plasma accelerator (anode layer plasma accelerator or plasma accelerator with insulated channel, with cylindrical or race track configuration of emission slit). The target-emitter is bombarded by the ion beam accelerated in crossed ExB fields. Negative ions are extracted from the target surface with geometrical focusing and are accelerated by negative voltage applied between emitter and plasma, contacting with the plasma accelerator. Hall drift ion source has a special design with a space for passing of the emitted negative ions and sputtered particles through the positive ion source.
Absolute beam brightness detector
Authors: Dudnikov Vadim
Published: February 2012

In generally accepted emittance measurement, main attention is concentrated on emittance areas ɛx, ɛy occupied by desired part of ion beam in transverse phase space and shape of these areas. The absolute beam phase density (brightness) as usually is not measured directly and the average beam brightness B is calculated from a beam intensity I and the transverse emittances. In the ion source and low energy beam transport (LEBT) optimization, it is important to preserve the beam brightness because some aberration of ion optic and beam instabilities can decrease the brightness of the central part of ion beam significantly. For these brightness measurements, it is convenient to use an absolute beam brightness detector with the brightness determination from one short considered in this article.
Brightness enhancement of plasma ion source by utilizing anode spot for nano applications
Authors: Park Yeong-Shin , Lee Yuna , Kim Yoon-Jae , Park Man-Jin , Moon Dae Won , Chung Kyoung-Jae , Hwang Y. S.
Published: February 2012

Anode spots are known as additional discharges on positively biased electrode immersed in plasmas. The anode spot plasma ion source (ASPIS) has been investigated as a high brightness ion source for nano applications such as focused ion beam (FIB) and nano medium energy ion scattering (nano-MEIS). The generation of anode spot is found to enhance brightness of ion beam since the anode spot increases plasma density near the extraction aperture. Brightness of the ASPIS has been estimated from measurement of emittance for total ion beam extracted through sub-mm aperture. The ASPIS is installed to the FIB system. Currents and diameters of the focused beams with/without anode spot are measured and compared. As the anode spot is turned on, the enhancement of beam current is observed at fixed diameter of the focused ion beam. Consequently, the brightness of the focused ion beam is enhanced as well. For argon ion beam, the maximum normalized brightness of 12 300 A/m2 SrV is acquired. The ASPIS is applied to nano-MEIS as well. The ASPIS is found to increase the beam current density and the power efficiency of the ion source for nano-MEIS. From the present study, it is shown that the ASPIS can enhance the performance of devices for nano applications.
Extraction of negative hydrogen ions from a compact 14 GHz microwave ion source
Authors: Wada M. , Kasuya T. , Kenmotsu T. , Maeno S. , Nishida T. , Nishiura M. , Shinto K. , Yamaoka H.
Published: February 2012

A pair of permanent magnets has formed enough intensity to realize electron cyclotron resonance condition for a 14 GHz microwave in a 2 cm diameter 9 cm long alumina discharge chamber. A three-electrode extraction system assembled in a magnetic shielding has formed a stable beam of negative hydrogen ions (H−) in a direction perpendicular to the magnetic field. The measured H− current density was about 1 mA/cm2 with only 50 W of discharge power, but the beam intensity had shown saturation against further increase in microwave power. The beam current decreased monotonically against increasing pressure.
Influence of discharge gap on the discharge stability in a short vacuum arc ion source
Authors: Chen L. , Zhang G. L. , Jin D. Z. , Yang L. , Dai J. Y.
Published: February 2012

The influence of the discharge gap between cathode and anode on the discharge stability in a short vacuum arc (SVA) ion source is presented in this paper. Planar cathode and cylindrical hollow anode made of titanium are investigated. There is a great need in present accelerator injection research for SVA source to produce the small deviation of the ion current beam. Current research shows that increasing the short discharge gap can reduce the level of ion current deviation and ion charge deviation from 29% and 31% to 15% and 17%, respectively. A microplasma plume generation mechanism in SVA and scanning electron microscopic results can be used to explain this interesting phenomenon.
Analysis of H atoms in a negative ion source plasma with the non-equilibrium electron energy distribution function
Authors: Koga S. , Shibata T. , Terasaki R. , Kameyama N. , Hatayama A. , Bacal M. , Tsumori K.
Published: February 2012

In negative ion sources for the neutral beam injection, it is important to calculate H atom flux onto the plasma grid (PG) surface for the evaluation of H− production on the PG surface. We have developed a neutral (H2 molecules and H atoms) transport code. In the present study, the neutral transport code is applied to the analysis of the H2 and H transport in a NIFS-R&D ion source in order to calculate the flux onto the PG surface. Taking into account non-equilibrium feature of the electron energy distribution function (EEDF), i.e., the fast electron component, we have done the neutral transport simulation. The results suggest that the precise evaluation of the EEDF, especially in the energy range 15 eV < E < 30 eV is important for the dissociation rate of H2 molecules by the electron impact collision and the resultant H atom flux on the PG.
Multiple delivery cesium oven system for negative ion sources
Authors: Bansal G. , Bhartiya S. , Pandya K. , Bandyopadhyay M. , Singh M. J. , Soni J. , Gahlaut A. , Parmar K. G. , Chakraborty A.
Published: February 2012

Distribution of cesium in large negative ion beam sources to be operational in ITER, is presently based on the use of three or more cesium ovens, which operate simultaneously and are controlled remotely. However, use of multiple Cs ovens simultaneously is likely to pose difficulties in operation and maintenance of the ovens. An alternate method of Cs delivery, based on a single oven distribution system is proposed as one which could reduce the need of simultaneous operation of many ovens. A proof of principle experiment verifying the concept of a multinozzle distributor based Cs oven has been carried out at Institute for Plasma Research. It is also observed that the Cs flux is not controlled by Cs reservoir temperature after few hours of operation but by the temperature of the distributor which starts behaving as a Cs reservoir.
In-situ investigation of phase formation in nanocrystalline (Co97.5Fe2.5)89Zr7B4 alloy by high temperature x-ray diffraction
Authors: Kernion Samuel J. , Ohodnicki Paul R. , McHenry Michael E.
Published: February 2012

Crystallization and phase evolution in an (Co97.5Fe2.5)89Zr7B4 amorphous alloy was studied by high temperature x-ray diffraction (HTXRD) and transmission electron microscopy (TEM). Co-based nanocomposite alloys have zero magnetostriction and a strong response to magnetic field annealing making them interesting for sensor and high frequency power applications. Amorphous alloys, synthesized by single roll melt-spinning, develop a nanocomposite structure after primary crystallization. After annealing at 540 °C for 1 h, TEM images and diffraction patterns confirm a grain size of 19 nm and the presence of at least two phases. HTXRD results show preferential body centered cubic (bcc) nucleation and formation of multiple phases at various stages of crystallization. Only the face centered cubic (fcc) phase remained at temperatures above 600 °C. On heating, the lattice parameter of the fcc phase increases at a rate higher than expected from thermal expansion. This is partially explained by an increase in the Fe-concentration in fcc crystallites.
Effect of attrition time on the microwave permeability of magnetic Fe-Si-Al flakes
Authors: Han Mangui , Liang Difei , Xie Jianliang , Deng Longjiang
Published: February 2012

Fe-Si-Al particles with irregular shapes have been successfully milled into flaky shapes by attrition for 10, 20, and 30 h, respectively. The attrition time has very small effect on the static magnetic properties, but shows strong effects on the high frequency properties (permittivity and permeability). With increasing the attrition time, the values of permeability can be obviously enhanced, especially at lower frequencies. The high frequency permittivity values of flakes milled for 30 h are much larger than those of particles milled for 10 or 20 h. A multiple relaxation processes model has been used to study the permeability dispersion behaviors. Analysis show the variation of shape anisotropy could be the main cause for the observed changes in permeability dispersion behaviors. However, the electromagnetic wave absorption properties of composites filled with these flaky shape Fe-Si-Al particles are found deteriorated when the particles have been milled for longer time.
Fabrication of L1-MnAl perpendicularly magnetized thin films for perpendicular magnetic tunnel junctions
Authors: Hosoda Masaki , Oogane Mikihiko , Kubota Miho , Kubota Takahide , Saruyama Haruaki , Iihama Satoshi , Naganuma Hiroshi , Ando Yasuo
Published: February 2012

Structural and magnetic properties of MnAl thin films with different composition, growth temperature, and post-annealing temperature were investigated. The optimum condition for fabrication of L10-MnAl perpendicularly magnetized thin film deposited on Cr-buffered MgO single crystal substrate was revealed. The results of x ray diffraction indicated that the MnAl films annealed at proper temperature had a (001)-orientation and L10-ordered structure. The L10-ordered films were perpendicularly magnetized and had a large perpendicular anisotropy. In addition, low surface roughness was achieved. For the optimized fabrication condition, the saturation magnetization Ms of 600 emu/cm3 and perpendicular magnetic anisotropy Ku of 1.0 × 107 erg/cm3 was obtained using the Mn48Al52 target at deposition temperature of 200 °C and post-annealing temperature of 450 °C.