bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous quantification of 2′,2′‐difluorodeoxycytidine and 2′,2′‐difluorodeoxyuridine nucleosides and nucleotides in white blood cells using porous graphitic carbon chromatography coupled with tandem mass spectrometry
Authors: Jansen Robert S. , Rosing Hilde , Schellens Jan H. M. , Beijnen Jos H. 
Published: August 2009

AbstractA novel assay for the simultaneous quantification of the widely used anticancer agent 2′,2′‐difluorodeoxycytidine (gemcitabine; dFdC), its deaminated metabolite 2′,2′‐difluorodeoxyuridine (dFdU) and their mono‐, di‐ and triphosphates (dFdCMP, dFdCDP, dFdCTP, dFdUMP, dFdUDP and dFdUTP) in peripheral blood mononuclear cells (PBMCs) is described. Separation of all eight compounds was achieved within 15 min using a porous graphitic carbon column (Hypercarb) with a gradient from 0 to 25 mM ammonium bicarbonate in acetonitrile/water (15:85, v/v). Calibration ranges in PBMC lysate from 4.29 to 429, 29.0 to 2900, 31.4 to 3140 and 36.9 to 3690 nM for dFdC, dFdCMP, dFdCDP and dFdCTP and from 42.1 to 4210, 25.4 to 2540, 43.2 to 4320 and 52.7 to 5270 nM for dFdU, dFdUMP, dFdUDP and dFdUTP, respectively, were validated. Accuracies were within 82.3–119% at the lower limit of quantification (LLOQ) and the precisions were less than 20.0%. At the other tested levels accuracies were within 91.4–114% and precisions less than 14.9%. Mixtures of 13C,15N2‐labeled dFdC and dFdU nucleotides were synthesized and used as internal standards. Whole blood samples showed extensive ongoing dFdC metabolism when stored at room temperature, but not on ice‐water, which made the addition of enzyme inhibitors unnecessary. Stock solutions and samples were stable under all analytically relevant conditions. The method was successfully applied to clinical samples. Copyright © 2009 John Wiley & Sons, Ltd.
Detection of aminothiols through surface‐assisted laser desorption/ionization mass spectrometry using mixed gold nanoparticles
Authors: Chiang Ni‐Chen , Chiang Cheng‐Kang , Lin Zong‐Hong , Chiu Tai‐Chia , Chang Huan‐Tsung 
Published: August 2009

AbstractWe have employed mixtures of two differently sized (average diameters: 3.5 and 14 nm) gold nanoparticles (Au NPs) as selective probes and matrices for the determination of aminothiols using surface‐assisted laser desorption/ionization mass spectrometry (SALDI‐MS). When using 38 and 150 pM solutions of the 3.5‐ and 14‐nm Au NPs, respectively, as the probe and matrix, SALDI‐MS provided limits of detection (signal‐to‐noise ratio = 3) of 2, 20, and 44 nM for 1.0 mL solutions of glutathione (GSH), cysteine (Cys), and homocysteine, respectively. The signal intensities of these analytes varied by less than 20% for SALDI‐MS analyses recorded over 50 sample spots; in contrast, they varied by as much as 60% when using a conventional matrix (2,5‐dihydroxybenzoic acid). We validated the practicality of this approach – with its advantages of sensitivity, reproducibility, rapidity, and simplicity – through the analysis of GSH in MCF‐7 cell lysates and Cys in plasma. Copyright © 2009 John Wiley & Sons, Ltd.
Belowground fate of 15N injected into sweetgum trees (Liquidambar styraciflua) at the ORNL FACE Experiment
Authors: Garten Charles T. , Brice Deanne J. 
Published: August 2009

AbstractNitrogen (N) cycling can be an important constraint on forest ecosystem response to elevated atmospheric CO2. Our objective was to trace the movement of 15N, injected into tree sap, to labile and stable forms of soil organic matter derived partly from the turnover of tree roots under elevated (545 ppm) and ambient (394 ppm) atmospheric CO2 concentrations at the Oak Ridge National Laboratory (ORNL) FACE (Free‐Air Carbon Dioxide Enrichment) Experiment. Twenty‐four sweetgum trees, divided equally between CO2 treatments, were injected with 3.2 g 15N‐ammonium sulfate (99 atom %), and soil samples were collected beneath the trees over a period of 89 weeks. For 16 cm deep soil samples collected beneath the study trees, there was 28% more fine root (less than or equal to 2 mm diameter) biomass under elevated CO2 (P = 0.001), but no significant treatment effect on the amounts of necromass, coarse root biomass, or on the N concentrations in tree roots and necromass. Nitrogen‐15 moved quickly into roots from the stem injection site and the 15N content of roots, necromass, and labile organic matter (i.e. particulate organic matter, POM) increased over time. At 89 weeks post‐injection, approximately 76% of the necromass 15N originated from fine root turnover. Nitrogen‐15 in POM had a relatively long turnover time (47 weeks) compared with 15N in roots (16 to 22 weeks). Over the 1.7 year period of the study, 15N moved from roots into slower cycling POM and the disparity in turnover times between root N and N in POM could impose progressive limitations on soil N availability with stand maturation irrespective of atmospheric CO2, especially if the release of N through the decomposition of POM is essential to sustain forest net primary production. Published in 2009 by John Wiley & Sons, Ltd.
Minors in random regular graphs
Authors: Fountoulakis Nikolaos , Kühn Daniela , Osthus Deryk 
Published: August 2009

AbstractWe show that there is a constant c so that for fixed r ≥ 3 a.a.s. an r‐regular graph on n vertices contains a complete graph on $ c\sqrt{n} $ vertices as a minor. This confirms a conjecture of Markström (Ars Combinatoria 70 (2004) 289–295). Since any minor of an r‐regular graph on n vertices has at most rn/2 edges, our bound is clearly best possible up to the value of the constant c. As a corollary, we also obtain the likely order of magnitude of the largest complete minor in a random graph Gn,p during the phase transition (i.e., when pn → 1). © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009
Prenatal ultrasound exposure and children's school performance at age 15–16: follow‐up of a randomized controlled trial
Authors: Stålberg K. , Axelsson O. , Haglund B. , Hultman C. M. , Lambe M. , Kieler H. 
Published: August 2009

AbstractObjectiveTo evaluate the association between prenatal ultrasound exposure and school performance at 15–16 years of age.MethodsThe study population consisted of children born to women who participated in a randomized controlled trial on the second‐trimester ultrasound examination in Sweden from 1985 to 1987. Information about the children's grades when graduating from primary school and information on socioeconomic factors was obtained from Swedish nationwide registers. Comparisons were made using linear and logistic regression analyses according to randomization to ultrasound, ultrasound exposure in the second trimester and ultrasound exposure at any time during pregnancy. Boys and girls were analyzed separately.ResultsOf the 4756 singleton children from the randomized trial, we identified 4458 (94%) in the National School Register. There were no statistically significant differences in school performance for boys or girls according to randomization or exposure to ultrasound in the second trimester. Compared to those who were unexposed, boys exposed to ultrasound at least once at any time during fetal life had a tendency towards lower mean school grades in general (−4.39 points; 95% CI, −9.59 to 0.81 (max possible, 320) points) and in physical education (−0.45 points; 95% CI, −0.91 to 0.01 (max possible, 20) points), but the differences did not reach significance.ConclusionIn general, routine ultrasound examination in the second trimester had no effect on overall school performance in teenagers. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
l‐Cysteine improves survival and growth of mesothelial cells after freezing
Authors: Bird Stephen D. , Walker Robert J. , Legge Michael 
Published: August 2009

AbstractEnzymic isolation, cryopreservation and culture of cells places considerable demand on intracellular antioxidant thiol status. Thiol status is carefully regulated in the cell by the balance of reduced and oxidized thiol species, including glutathione (GSH/GSSG) and l‐cysteine (l‐Cys/l‐CySS disulphide). These play a pivotal role in redox signaling, cell attachment, proliferation and differentiation. Thiol depletion exposes cells to “thiol debt”, increasing their vulnerability to sustained pro‐oxidant attack and injury. This study focused on the ability of l‐Cys‐enriched medium to enhance survival and growth of human peritoneal mesothelial cells (hPMC) after prolonged storage at −196 °C. HPMC derived from human omentum suspended in freezing solution (90% foetal bovine serum, 10% dimethylsulfoxide) were cryopreserved at passage 1 for 6 years. Thawed cells cultured in medium M199 plus or minus l‐Cys (0.25 mmol/L) were subjected to morphological, growth, ultrastructural studies, RT‐PCR and cell signaling studies to assess cell function after cryopreservation. Viability of thawed cells was lower (85 ± 3%) than non‐frozen control cells (98 ± 2% viable). l‐Cys added to the cryopreservation fluid and the post‐thaw medium increased cell viability to 94 ± 2%. Cell growth plus l‐Cys was 2‐fold greater compared with the minus l‐Cys controls. The former had a cobblestone appearance. Ultrastructural studies showed lamellar bodies, indicative of surfactant production not evident in cells in minus l‐Cys, which were a fibroblastic appearance. l‐Cys treated hPMC constitutively expressed message for growth factors, TGFβ1, PDGF‐A, PDGF‐B and PDGFβ‐receptor. The functionality of the PDGFβ‐receptor was confirmed in fura‐2 loaded cells with release of intracellular calcium when challenged with exogenous PDGF‐BB. The addition of reduced thiols to culture media may have wider application in survival and enhance cell‐based therapies.
A failure of conflict to modulate dual-stream processing may underlie the formation and maintenance of delusions
Authors: Speechley W.J. , Murray C.B. , McKay R.M. , Munz M.T. , Ngan E.T.C. 
Published: August 2009

AbstractBackgroundDual-stream information processing proposes that reasoning is composed of two interacting processes: a fast, intuitive system (Stream 1) and a slower, more logical process (Stream 2). In non-patient controls, divergence of these streams may result in the experience of conflict, modulating decision-making towards Stream 2, and initiating a more thorough examination of the available evidence. In delusional schizophrenia patients, a failure of conflict to modulate decision-making towards Stream 2 may reduce the influence of contradictory evidence, resulting in a failure to correct erroneous beliefs.MethodDelusional schizophrenia patients and non-patient controls completed a deductive reasoning task requiring logical validity judgments of two-part conditional statements. Half of the statements were characterized by a conflict between logical validity (Stream 2) and content believability (Stream 1).ResultsPatients were significantly worse than controls in determining the logical validity of both conflict and non-conflict conditional statements. This between groups difference was significantly greater for the conflict condition.ConclusionsThe results are consistent with the hypothesis that delusional schizophrenia patients fail to use conflict to modulate towards Stream 2 when the two streams of reasoning arrive at incompatible judgments. This finding provides encouraging preliminary support for the Dual-Stream Modulation Failure model of delusion formation and maintenance.
Experiments on the ectoparasitic deer ked that often attacks humans; preferences for body parts, colour and temperature
Authors: Kortet R. , Härkönen L. , Hokkanen P. , Härkönen S. , Kaitala A. , Kaunisto S. , Laaksonen S. , Kekäläinen J. , Ylönen H. 
Published: August 2009

AbstractThe deer ked (Lipoptena cervi) can fail in its host search. Host search fails when an individual deer ked irreversibly accepts a host unsuitable for its reproduction (e.g. a human) and drops its wings. In northern Europe, the main host of the deer ked is the moose (Alces alces). The deer ked is increasingly causing serious problems for humans (for example, causing deer ked dermatitis) and is considered a threat for the recreational use of forests. The adult deer ked flies in early and mid-autumn to search for a host. Our aims were: (i) to study whether there are ways to avoid deer ked attacks by wearing particular clothing, and (ii) to evaluate deer ked host choice. Using human targets, we explored the cues the deer ked uses for host selection. We studied which part of the host body deer keds target and if body colour and temperature affect their choice. In our experiments, deer keds landed more on dark and red clothing than on white clothing. Moreover, deer keds mostly attacked the upper body parts and preferred the back side of the body over the front side. Finally, deer keds preferred the warmest areas of the host.
Tan Cheng Lock and the Chinese Education Issue in Malaya
Authors: Ee Tan Liok 
Published: August 2009

These memorable words were spoken by Tan Cheng Lock, a man who did not speak any Chinese himself, when addressing a meeting of representatives of Chinese School Committees and Chinese School Teachers' Associations on 9 November 1952. Speaking as president of the Malayan Chinese Association (MCA), Tan went on in his speech to promise thatAt this critical juncture in the history of the growth and development of Chinese education and culture in Malaya … its cause has the full support of the Malayan Chinese Association.Tan's speech, and the presence of three other MCA leaders at the meeting, were the first clear indications that the MCA was prepared to take a consolidated stand with other Chinese organizations, in particular the United Chinese School Teachers' Association (UCSTA), and the United Chinese Schools' Committees' Association (UCSCA), on the issue of Chinese education. The MCA's decision was greeted by a chorus of approval from the Chinese press which described the 9 November meeting as an unprecedented manifestation of Chinese unity and from leading shetuan, or Chinese social organizations, which expressed their full support for the meeting's stand on Chinese education.
On the Possible Cham Origin of the Philippine Scripts
Authors: Wade Geoff 
Published: August 2009

I. The Philippine ScriptsIn 1593, there was printed in Manila a most remarkable xylographic (wood-block) book, comprising Juan de Plascenia'sDoctrina Christianain Spanish, romanized Tagalog and Tagalog script (see Fig. 1). While there is still some debate as to whether this was the first book to be published in the Philippines, there appears little doubt that it constitutes the earliest extant printed example of any Philippine script.
“Syrup in the Wheels of Progress”: The Inefficient Organization of the Philippine Sugar Industry
Authors: Billig Michael S. 
Published: August 2009

While the organization of the Philippine sugar industry evolved to promote and balance the short-term interests of planters, millers and traders, it now undermines the industry and threatens the economic fortunes of those who depend upon it. By perpetuating inefficiency and fostering a frenzy of trading that affords inordinate profits for the least productive sector, this structure has become the major obstacle to restoring the Philippines to its former status as one of the world's most efficient and technologically advanced producers of cane sugar. As efficiency falls further behind that of other sugar producing countries, and as industrial consumers become more disgruntled with paying high prices for sugar, the nation risks the collapse of an industry that has already proven vulnerable to intermittent crises. The last time a crisis occurred — in the mid-1980s — planters faced foreclosure, mills stood idle, and workers and their families suffered malnutrition and dislocation, leading commentators to refer to Negros, the nation's premier sugar-growing island, as “Asia's Ethiopia” and a “social volcano”. While conditions have improved since the EDSA Revolution, the structure that has emerged does little to encourage productivity, efficiency and fairness. Since the industry continues to employ 500,000 workers, with as many as three million dependents, a collapse would lead to mass displacement, hunger, and political upheaval.This paper will outline the history of the Philippine sugar industry, examine its current structure, and describe the political and economic forces that sustain it. My first contention is that the institutional organization, rather than government policy, cultural attitudes, or neo-colonial dependency, is fundamentally responsible for the poor performance of the industry in recent decades and, unless major changes are forthcoming, will be mainly responsible for its ultimate demise.
The OSS in Laos: The 1945 Raven Mission and American Policy
Authors: Dommen Arthur J. , Dalley George W. 
Published: August 2009

In September 1945, the U.S. Office of Strategic Services (OSS) headquarters in Kunming dispatched a mission to Laos. The purpose and composition of the mission were described on the first page of the mission's report as follows:The Raven Mission was put on by OSS in cooperation with AGAS [Air Ground Aid Section], and parachuted near Vientiane, French Indo-China on 16 September 1945 for Prisoner of War relief work. This mission was activated following a request by G-5 SOS. The mission was composed of the following personnel: Major [Aaron] Bank, Mission Leader; Major [Charles] Holland, Executive Officer; Lt. [Alger] Ellis, Asst. Executive Officer; Lt. Phelan, AGAS Representative; Lt. [B. Hugh] Tovar, Reports Officer; Lt. Reese, Reports Officer; T/5 McKowan, Radio Operator; T/5 Blandin, Medic; Lao Trug [Luu], Interpreter.
“The Whole Moon was Eaten”: Southeast Asian Eclipse Calculation
Authors: Eade J.C. , Gislén Lars 
Published: August 2009

One might classify earthquakes and volcanic eruptions as “natural disasters”, whereas comets and eclipses might be described merely as “natural curiosities”. In earlier times, however, all were equally frightening, signs that the gods were angry.A form of protection against eclipses was available, however, in the sense that prediction provided a means of countering the event. Consequently one main function of the astronomer/astrologer (henceforth “hora”) in his society was to warn his patron that the sky would darken and the birds stop singing at such and such a time on such and such a day.
Human reproductive strategies: An emerging synthesis?
Authors: Del Giudice Marco 
Published: August 2009

AbstractIn the first part of this response, commentators' critiques to the target article are reviewed and addressed. The main discussion topics are the role of attachment in developmental plasticity; the relationship between attachment, mating, and reproductive strategies; the existence, magnitude, and developmental timing of sex differences in attachment; the adaptiveness of insecure styles; and the neurobiology of attachment and reproduction. The model's assumptions are clarified, and a number of methodological issues that can confound the interpretation of research findings are examined. In the second part, various proposals made by commentators are synthesized, and directions for future research and theoretical improvement are outlined. In addition, the issue of disorganized and fearful attachment is tentatively addressed. It is argued that different theoretical perspectives are converging toward a consistent and comprehensive theory of human reproductive strategies.
Entropy and its variational principle for non-compact metric spaces
Authors: PATRÃO MAURO 
Published: August 2009

AbstractIn the present paper, we introduce a natural extension of Adler, Konheim and MacAndrew topological entropy for proper maps of locally compact separable metrizable spaces and prove a variational principle which states that this topological entropy, the supremum of the Kolmogorov–Sinai entropies and the minimum of the Bowen entropies always coincide. We apply this variational principle to show that the topological entropy of automorphisms of simply connected nilpotent Lie groups always vanishes. This shows that the Bowen formula for the Bowen entropy of an automorphism of a non-compact Lie group with respect to some invariant metric is just an upper bound for its topological entropy.
Western Impact on East Sumatra and North Tapanuli: The Roles of the Planter and the Missionary
Authors: Pelzer Karl J. 
Published: August 2009

The two administrative units of Sumatra with which this paper is concerned are East Sumatra, stretching along the Strait of Malacca, and North Tapanuli, extending from the mountainous interior around Lake Toba to the Indian Ocean.At the beginning of the nineteenth century, East Sumatra and Tapanuli (except for a small number of Indian-Ocean settlements and trading posts in the latter) were completely outside of the political sphere of interest of European powers. The Treaty of London of 1824, however, delineated Malaya as a British sphere of interest and Sumatra as a Dutch sphere. But it was nearly another forty years before the Dutch turned their attention to East Sumatra and North Tapanuli. In the forward movement which then began, planters and Christian missionaries played highly significant and critical roles; in the pioneer decades they were actually either ahead of the flag or were overshadowing the colonial government officials.
History and Sociology of the Chinese in Cambodia Prior to the French Protectorate
Authors: Willmott W. E. 
Published: August 2009

It is evident from the brief historical survey presented in this paper that the French found in Cambodia well-established Chinese communities with a long tradition of indirect rule. My argument may be summarised in four propositions:1. Contact between Cambodia and China has continued more or less uninterrupted since the first century of this era — and perhaps longer. Unlike early Indian contact, which produced distinctly Indian forms in the indigenous cultures of Southeast Asia, contact with China appears to have left them relatively unmarked. Khmer culture is definitely not sinic in language, social structure, religion, or the arts.2. The long history of Chinese contact was not associated with extensive Chinese settlement in Cambodia until the fifteenth century, when there occurred a marked change in the nature of the Cambodian economy. Throughout the Chen-la and the Angkorean periods, the relative homogeneity of the country did not encourage internal trade, and the small amount of foreign trade evident in the capital was limited almost entirely to luxury goods for the court. After 1400, the Cambodian economy came to depend more and more upon trade, a phenomenon that was associated with the establishment of a growing Chinese population in Cambodia, primarily in Phnom-Penh.3. The evidence of trade relations and large migrations suggests that by the middle of the nineteenth century the Chinese population of Phnom-Penh was mainly Cantonese, possibly with a smaller number of Hokkien. In Kampot, on the other hand, along the coast of the Gulf of Siam, a large number of Hainanese settled following the establishment, in the eighteenth century, of a trading centre at Hatien. We do not know the size of this population, but we do know that by 1860 it was primarily engaged in growing pepper. It is clear that by the time of the French Protectorate was established in 1864, the Chinese community in Phnom-Penh, whatever its make-up, numbered in the thousands and controlled practically all the trade of the country, foreign and domestic.4. The concept of indirect rule over the Chinese in Cambodia dates from at least the beginning of the eighteenth century. This system was not very formal, however, and the legally denned system of congregations in neighbouring Annam, dating from 1814, became the model for the French colonial administrators when they eventually came to consider the “Chinese problem” in Cambodia.