bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of temperature and darkness on embryonic diapause termination in dormant Artemia cysts that have never been desiccated
Authors: Nambu Ziro , Tanaka Shin , Nambu Fumiko , Nakano Masahiro
Published: November 2007

Environmental cues for embryonic diapause termination (EDT) were investigated in the laboratory‐produced encysted dormant embryos of the brine shrimp, Artemia franciscana. The cysts were spawned and kept throughout in a 2% sea salt solution. They were activated by various temperatures of the temperate zones or by continuous dark condition (DD), resulting in a state of EDT, and were thereafter able to resume their subsequent development and hatch under appropriate conditions. The level of EDT was conveniently assayed by a hatch test observed within 2 days at 28°C under continuous light condition (LL). A cold treatment of the newly spawned dormant cysts, at 4°C under DD for more than 100 days, resulted in more than 95% hatch of the dormant cysts. Similar treatments of the dormant cysts but at room temperature or 28°C led to significantly different results (30–40% hatch). Almost all the residual non‐hatched cysts derived from the above could hatch after an additional cold treatment (at 4°C under DD for about 100 days). This might prove to be latent partial bivoltine in Artemia. Meanwhile, a rearing condition (28°C under LL) induced the newly spawned cysts to hatch scatteredly at and after 1 month, resulting in 22% cumulative hatch on the 92nd day after spawning. When the newly spawned dormant cysts were pretreated at 28°C under DD for 5 or 14 days and then reared at 28°C under LL, the cumulative hatch significantly increased (60%). These results are discussed with respect to probable diapause regulator(s) involved in EDT. J. Exp. Zool. 309:17–24, 2008. © 2007 Wiley‐Liss, Inc.
Primary sex ratio in fertilized chicken eggs (Gallus gallus domesticus) depends on reproductive age and selection
Authors: Klein Sabine , Grossmann Roland
Published: November 2007

Recent studies of several avian species have shown that the primary sex ratio can change as a result of prevailing conditions, especially in the female bird's first reproductive season. In this study, we sought to determine the primary sex ratio of the first 15 eggs produced in chickens. The study compared chickens which had been commercially selected over many generations for egg‐laying performance (Leghorns) with “fancy‐bred” chickens selected for feather coloration. These fancy‐bred chickens are known to reach reproductive maturity 4 weeks later than Leghorns. A group of precociously matured Leghorn chickens was produced by modification of diet and day length to investigate the effect of age at reproductive maturity on sex ratio. Sex diagnosis was performed on embryos which had died on or before embryonic day 10 by polymerase chain reaction (PCR). Living embryos were allowed to hatch before sex diagnosis. The group of precociously matured White Leghorns reached egg‐laying age 3 weeks earlier than normal. In this group, the sex ratio of hatched chicks was in tendency skewed to females. In the White Leghorns maintained under normal conditions for commercial layers, sex ratio was balanced with a tendency to more males only in the first five eggs. In the group of fancy‐bred chickens, the primary sex ratio was significantly biased toward more males and dependent on the laying sequence. Our data suggested a sex ratio bias toward males in the very first eggs at onset of reproduction in chickens depending on genetic background. J. Exp. Zool. 309:35–46, 2008. © 2007 Wiley‐Liss, Inc.
There exist graphs with super‐exponential Ramsey multiplicity constant
Authors: Fox Jacob
Published: November 2007

The Ramsey multiplicity M(G;n) of a graph G is the minimum number of monochromatic copies of G over all 2‐colorings of the edges of the complete graph Kn. For a graph G with a automorphisms, ν vertices, and E edges, it is natural to define the Ramsey multiplicity constant C(G) to be $\lim_{{n} \to \infty} {M}(G;n){a/v}!{n \choose v}$, which is the limit of the fraction of the total number of copies of G which must be monochromatic in a 2‐coloring of the edges of Kn. In 1980, Burr and Rosta showed that 0 ≥ C(G) ≤ 21−E for all graphs G, and conjectured that this upper bound is tight. Counterexamples of Burr and Rosta's conjecture were first found by Sidorenko and Thomason independently. Later, Clark proved that there are graphs G with E edges and 2E−1C(G) arbitrarily small. We prove that for each positive integer E, there is a graph G with E edges and C(G) ≤ E−E/2 + o(E). © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 89–98, 2008
Phytase–phytate–pectin hypothesis and quality of legumes cooked in calcium solutions
Authors: Galiotou‐Panayotou Maria , Kyriakidis Nikolaos B , Margaris Ioannis
Published: November 2007

Hard‐to‐cook and easy‐to‐cook bean and lentil seeds were boiled in water containing calcium ions at concentrations of 0, 40, 80, 120 and 160 mg L−1 and their texture and concentration of phytate and various peptic compounds were measured. In order to minimise matrix effects, hard‐to‐cook seeds were prepared from easy‐to‐cook seeds by soaking them at 50 °C. It was found that, as calcium ion concentration increased, phytate concentration decreased and seed hardness increased. Also, during soaking and cooking, phytate and peptic compounds were leached into the water. Losses were larger for hard‐to‐cook seeds than for easy‐to‐cook seeds. These results are consistent with the proposed theory that the formation of hard‐to‐cook legume seeds involves an interaction among divalent cations, phytate and peptic compounds, which is based on the phytase–phytate–pectin hypothesis. Copyright © 2007 Society of Chemical Industry
Simultaneous determination of nine flavonoids and qualitative evaluation of Herba Epimedii by high performance liquid chromatography with ultraviolet detection
Authors: Huang Hao , Liang Mingjin , Zhang Xinmin , Zhang Chuan , Shen Ziyin , Zhang Weidong
Published: November 2007

A simple high performance liquid chromatographic method has been developed for the determination of nine flavonoids in Herba Epimedii, including quercetin‐3‐O‐glucoside, epimedin A, hexandraside A, epimedin B, epimedin C, icariin, icariside I, icariside II, and icaritin. The chromatographic separation was performed on a Diamonsil C18 column (5 μm, 250×4.6 mm) with gradient elution by acetonitrile–0.5% acetic buffer (adjusted to pH 5.00 with triethylamine). Methodological validation gave acceptable linearities (r2 >0.9992) and recoveries (ranging from 98.9 to 102.4%). The limits of detection of these flavonoids ranged from 16.3 to 83.3 ng. The results indicated that the contents of flavonoids in Herba Epimedii varied significantly from habitat to habitat with contents ranging from 0.05 to 39.0 mg/g. Twenty five Herba Epimedii samples prepared from five different botanical materials were investigated by the established method, and the results showed the influence of the botanical material and the habitat on the quality of Herba Epimedii. The proposed method is simple, effective, and suitable for the evaluation of this traditional Chinese medicine.
Knowledge management audit in a higher educational institution: a case study
Authors: Biloslavo Roberto , Trnavčevič Anita
Published: November 2007

In the paper, we discuss the available research in the field of knowledge management (KM) from the specific perspective of higher educational (HE) institutions, as organisations comprised of experts. Based on the literature review, we develop a KM audit instrument and apply it to a specific HE institution in order to assess the status of its KM processes. From our study, we can conclude that even if an institution is ‘academic’ in nature and apparently successful, this fact does not necessarily mean that KM processes are institutionalised within the organisation. From this point of view, a HE institution is likely to be subject to the same limitations as any other organisation in the knowledge business. Our paper further gives recommendations to managers of HE institutions on how to assess the effectiveness of KM in their organisations as well as providing information for other researchers who want to conduct a KM audit in similar organisations. Copyright © 2007 John Wiley & Sons, Ltd.
Fabrication and Characterization of Ionic Conducting Nanofibers
Authors: Laforgue Alexis , Robitaille Lucie , Mokrini Asmae , Ajji Abdellah
Published: November 2007

The electrospinning method was used to fabricate nanostructures of Nafion‐poly(vinyl alcohol) (PVA) and Nafion‐poly(ethylene oxide) (PEO). Depending on the ratio between the two polymers, nanospheres and/or nanofibers could be obtained in a reproducible manner. The Nafion‐PVA mats were found to be more conductive than the Nafion‐PEO ones, possibly because of their better mechanical properties when swollen by water. The fiber morphology was always found to be more conductive than the sphere morphology. However, all electrospun mats presented ionic conductivities slightly lower than extruded Nafion 115 or Nafion‐PVA cast films.

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Thermally Stabilized Blue Luminescent Poly(p‐phenylene)s Covered with Polyhedral Oligomeric Silsesquioxanes
Authors: Miyake Junpei , Chujo Yoshiki
Published: November 2007

A novel series of poly(p‐phenylene)s (PPPs) with polyhedral oligomeric silsesquioxanes (POSSs) on their side chains was prepared. The obtained POSS‐modified PPPs are as follows: 25POSS‐PPP (2b, containing 25 mol‐% of POSS units in all side chains), 50POSS‐PPP (2c, containing 50 mol‐% of POSS units in all side chains), 100POSS‐PPP (2d, containing 100 mol‐% of POSS units in all side chains), and 0POSS‐PPP (2a, as a blank polymer). Films polymer 2d showed the same absorption and photoluminescence (PL) spectra as those in CHCl3 solution, indicating that bulky POSS units strongly suppressed intermolecular aggregation of the PPP backbone. Polymer 2d showed the same PL spectra even after thermal annealing at 150 °C for 6 h. This enhancement of PL stability is due to the significant effect of the bulky POSS units.

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New Azo Chromophore‐Containing Conjugated Polymers: Facile Synthesis by Using “Click” Chemistry and Enhanced Nonlinear Optical Properties Through the Introduction of Suitable Isolation Groups
Authors: Li Zhong'an , Zeng Qi , Yu Gui , Li Zhen , Ye Cheng , Liu Yunqi , Qin Jingui
Published: November 2007

A new series of azobenzene‐containing polyfluorenes have been successfully prepared through polymer reactions by the utilization of “click” chemistry. All the polymers were well characterized and soluble in common solvents. By the application of the concept of “suitable isolation group”, the macroscopic nonlinear optical (NLO) properties of the polymers could be boosted to as large as three times that of the polymer without isolation moieties. Also, all the polymers were thermally stable, and demonstrated good procesability, coupled with improved optical transparency. Thus, they are good candidates for the practical applications as new photonic materials.

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Occurrence of type A trichothecenes in conventionally and organically produced oats and oat products
Authors: Gottschalk Christoph , Barthel Jörg , Engelhardt Gabriele , Bauer Johann , Meyer Karsten
Published: November 2007

Among cereals, oats are known to be very frequently contaminated with type A trichothecenes and so they can play a major role in the exposition of the consumer to these mycotoxins. Seventy representative oat samples of both conventional and organic production were drawn at mills and at wholesale stage according to Commissions Regulation (EC) No 401/2006 and analyzed for nine type A trichothecenes by LC‐MS/MS. High contamination rates were found for most of the toxins in conventional as well as in organic products (e. g. 100% for T‐2 toxin or 99% for HT‐2 toxin). The mean concentration of T‐2/HT‐2 (sum of the toxins) was 17 ± 18 μg/kg (mean ± SD) in all samples, 27 ± 21 μg/kg in conventional, and 7.6 ± 4.6 μg/kg in organic products, respectively. The highest T‐2/HT‐2 level has been determined in conventionally produced oat flakes (85 μg/kg). The mean level of T‐2 tetraol (9.5 ± 7.7 μg/kg) in all samples was found to be even higher than that of T‐2 (5.1 ± 6.0 μg/kg), whereas levels of T‐2 triol, 4,15‐diacetoxyscirpenol, 15‐monoacetoxyscirpenol, and neosolaniol were considerably lower. For oats and oat products from organic farming contamination levels of T‐2, HT‐2, T‐2 triol, T‐2 tetraol, and neosolaniol were significantly lower. The results are discussed with respect to possible health risks for the consumer.
Freemartin in the amphibian Pleurodeles waltl: Parabiosis between individuals from opposite sex triggers both germ and somatic cells alterations during female gonad development
Authors: Dumond Helene , Maufroid Jean‐Pierre , Ko Chia‐I , Chardard Dominique , Chesnel Amand , Flament Stephane
Published: November 2007

Wild type embryos of the newt Pleurodeles waltl were used to realize parabiosis, a useful model to study the effect of endogenous circulating hormones on gonad development. The genotypic sex of each parabiont (ZZ male or ZW female) was determined early from the analysis of the sex chromosome borne marker peptidase‐1. In ZZ/ZZ and ZW/ZW associations, gonads develop according to genetic sex. In ZZ/ZW associations, the ZZ gonads differentiate as normal testes while ZW gonads development shows numerous alterations. At the beginning of sex differentiation, these ZW gonads possess a reduced number of germ cells and a reduced expression of steroidogenic factor 1 and P450‐aromatase mRNAs when compared to gonads from ZW/ZW associations. During gonad differentiation, conversely to the control situation, these germ cells do not enter meiosis as corroborated by chromatin status and absence of the meiosis entry marker DMC1; the activity of the estradiol‐producing enzyme P450‐aromatase is as low as in ZZ gonads. At adulthood, no germ cells are observed on histological sections, consistently with the absence of VASA expression. At this stage, the testis‐specific marker DMRT1 is expressed only in ZZ gonads, suggesting that the somatic compartment of the ZW gonad is not masculinized. So, when exposed to ZZ hormones, ZW gonads reach the undifferentiated status but the ovary differentiation does not occur. This gonad is inhibited by a process affecting both somatic and germ cells. Additionally, the ZW gonad inhibition does not occur in the case of an exogenous estradiol treatment of larvae. Mol. Reprod. Dev. 75: 439–449, 2008. © 2007 Wiley‐Liss, Inc.
Factorization for efficient solution of eigenproblems of adjacency and Laplacian matrices for graph products
Authors: Kaveh A. , Rahami H.
Published: November 2007

Many structural models can be generated as the graph products of two or three subgraphs known as their generators. The main types of graph products consist of Cartesian, strong Cartesian, direct, and lexicographic products. In this paper, a general method is presented for the factorization of these graph products, such that the eigenvalues of the entire graph are obtained as the union of the eigenvalues of the weighted subgraphs defined here. The adjacency and Laplacian matrices for each graph product are studied separately. For graphs with missing elements (cut‐outs), the eigenvalues are calculated with the additional use of the Rayleigh quotient approach. The main idea stems from the rules recently developed by the authors for block diagonalization of matrices. These products have many applications in computational mechanics, such as ordering, graph partitioning, dynamic analysis, and stability analysis of structures. Some of these applications are addressed in this paper. Copyright © 2007 John Wiley & Sons, Ltd.
Self‐rated health as predictor of medicine use in adolescence
Authors: Holstein Bjørn E. , Hansen Ebba Holme , Andersen Anette , Due Pernille
Published: November 2007

Purpose

To examine the association between self‐rated health (SRH) and medicine use for four common complaints: headache, stomach‐ache, difficulties in getting to sleep and nervousness, in a nationally representative sample of adolescents.

Methods

The study population comprised of all students in the fifth, seventh and ninth grade (mean ages 11.6, 13.6 and 15.6 years) in a random sample of schools in Denmark 2002, participation rate 90.6%, n = 4.824. The students reported health problems, medicine use, social and psychosocial conditions in an anonymous and standardized questionnaire. The outcome measure was self‐reported medicine use during the past month and the determinant was SRH measured by one item.

Results

There was an association between poor/fair SRH and medicine use for headache and stomach‐ache. The associations remained statistically significant even after adjustment for frequency of the complaint for which the medicine was used: OR (95%CI) for medicine use for headache was 1.54 (1.10–2.14) among boys with poor/fair SRH and 1.50 (1.12–2.03) among girls with poor/fair SRH. A similar association was found between poor SRH and medicine use for stomach‐ache for both boys (OR = 3.41 (2.09–5.55)) and girls (OR = 1.90 (1.36–2.67). Further, there was an association between poor/fair SRH and medicine use for difficulties in getting to sleep among girls, OR = 2.66 (1.26–5.63) but not among boys. There was no association between SRH and medicine use for nervousness.

Conclusion

Poor/fair SRH is associated with medicine use for aches among Danish adolescents. Copyright © 2007 John Wiley & Sons, Ltd.
The effect of structure on the thermoresponsive nature of well‐defined poly(oligo(ethylene oxide) methacrylates) synthesized by ATRP
Authors: Yamamoto Shin‐Ichi , Pietrasik Joanna , Matyjaszewski Krzysztof
Published: November 2007

Statistical copolymers of di(ethylene glycol) methyl ether methacrylate (MEO2MA) and tri(ethylene glycol) methyl ether methacrylate (MEO3MA) were synthesized by atom transfer radical polymerization (ATRP) providing copolymers with controlled composition and molecular weights ranging from Mn = 8,300–56,500 with polydispersity indexes (Mw/Mn) between 1.19 and 1.28. The lower critical solution temperature (LCST) of the copolymers increased with the mole fraction of MEO3MA in the copolymer over the range from 26 to 52 °C. The average hydrodynamic diameter, measured by dynamic light scattering, varied with temperature above the LCST. These two monomers were also block copolymerized by ATRP to form polymers with molecular weight of Mn = 30,000 and Mw/Mn from 1.12 to 1.21. The LCST of the block copolymers shifted toward the LCST of the major segment, as compared to the value measured for the statistical copolymers at the same composition. As temperature increased, micelles, consisting of aggregated PMEO2MA cores and PMEO3MA shell, were formed. The micelles aggregated upon further heating to precipitate as larger particles. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 194–202, 2008
Experimental Investigation of the Flow Pattern and Wall Pressure Distribution in a Silo with a Double‐Cone Insert
Authors: Wójcik Michał , Härtl Johannes , Ooi Jin Y. , Rotter Michael , Ding Songxiong , Enstad Gisle G.
Published: November 2007

The aim of this paper is to present a recent experimental investigation of the wall pressure distribution and flow pattern observed during the filling and emptying of a full‐scale silo, with and without, inserts. The experiments were carried out with sand, at the Dept. POSTEC in the Tel‐Tek Research Institute in Norway. The results show that the double‐cone insert had a strong influence on the flow and pressures in the silo. A skewed flow often occurred when the insert was installed.
Oxytocin increases 5α‐reductase activity of human prostate epithelial cells, but not stromal cells
Authors: Assinder S.J.
Published: November 2007

BACKGROUND

Oxytocin is known to modulate 5‐α‐reductase expression and has, therefore, been implicated in the etiology and novel pharmacological treatments of benign prostatic hyperplasia (BPH). These suggestions have been made in the absence of any direct evidence that oxytocin regulates expression or activity of 5‐α‐reductase isoenzymes in the human prostate. This study evaluated the effects of oxytocin on the activity and expression of 5‐α‐reductase isoenzymes I and II of human prostate stromal (PrSC; primary site of BPH development) and epithelial (PrEC) cells.

METHODS

Cell cultures were incubated with oxytocin, or oxytocin plus a specific oxytocin antagonist for 24 hr, and conversion of 3H‐Testosterone to dihydrotestosterone used to estimate total 5‐α‐reductase activity and to determine activity of both type I and type II isoenzymes. Fully quantitative real‐time RT‐PCR determined levels of expression of both isoenzymes following treatments.

RESULTS

Oxytocin significantly increased the total 5‐α‐reductase activity of PrEC but not of PrSC. 5‐α‐Reductase I gene expression and enzyme activity were also increased (P < 0.05) in PrEC by oxytocin. Oxytocin significantly increased type II activity, but not expression, in PrEC. Oxytocin did not significantly affect 5‐α‐reductase activity or expression in PrSC.

CONCLUSION

Both 5‐α‐reductase I and II are expressed in normal human prostate stromal and epithelial cells. Only 5‐α‐reductase isoenzymes of prostate epithelium are modulated by oxytocin. Prostate 68: 115–121, 2008. © 2007 Wiley‐Liss, Inc.
Resolving the controversy on the pH sensitivity of diamond surfaces
Authors: Dankerl M. , Reitinger A. , Stutzmann M. , Garrido J. A.
Published: November 2007

The pH sensitivity of the surface conductivity of H‐terminated diamond has been the subject of great controversy, regarding not only its absolute value but even its sign. In this contribution the effect of the reference electrode on the pH sensitivity is investigated. Thus, the pH response of diamond solution‐gate field effect transistors using Pt and Ag/AgCl reference electrodes has been measured. We demonstrate that the Pt electrode potential is itself pH dependent and over‐ compensates the pH sensitivity of the surface conductivity, which alters significantly the interpretation of the pH sensitivity experiments. If this effect is correctly taken into account the apparent controversy is resolved. The experimental results confirm that the pH sensitivity of the H‐terminated diamond surface conductivity does not follow the prediction of the transfer doping model. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fasting increases δ15N‐values in the uric acid of Anolis carolinensis and Uta stansburiana as measured by nondestructive sampling
Authors: Castillo Laura P. , Hatch Kent A.
Published: November 2007

Previous studies suggest that a nutritional/energetic state may be determined from the δ15N‐values of an animal's tissues. It has been hypothesized that if an animal is in a negative nutritional/energetic balance, 15N will be retained by the tissues preferentially and 14N preferentially excreted. Over time, this should cause enrichment of the δ15N‐values of the tissues. Tests of this hypothesis have met with mixed results. To date, these studies have focused on endotherms. Few studies have considered the effects of fasting on the 15N/14N ratios of substrates from ectotherms. We hypothesized that the δ15N‐values of tail tissue and uric acid of fasted lizards would increase over time, while that of the fed lizards would remain the same. We fasted five side‐blotched lizards (Uta stansburiana) and five green anoles (Anolis carolinensis) for 14 days. At the same time we fed six side‐blotched and four green anoles ad libitum. All lizards were given water ad libitum. During this period, we collected uric acid from each lizard daily and tail tissue on the first day of the study and on the last day of the study. We found the the δ15N‐values of uric acid of fasted lizards at the end of the study were 15N‐enriched compared with that of the control lizards in both species, probably due to a shift in amino acid source pools during fasting. However, we found no difference between treatment and controls in the δ15N‐values of the tails. Copyright © 2007 John Wiley & Sons, Ltd.
Detection, management, and follow‐up of pre‐malignant cervical lesions and the role for human papillomavirus
Authors: van Hamont D. , Bekkers R. L. M. , Massuger L. F. A. G. , Melchers W. J. G.
Published: November 2007

Cervical cytological pathology is common. Prevention of cervical cancer by detecting the disease process at an early and pre‐malignant stage is practised globally either through population‐based screening programmes (PSP) or through non‐organised ones. High‐grade cervical intraepithelial neoplasia (CIN) detected by cervical cytological screening is extensively visualised by colposcopy and successively treated by, for instance, large loop electro‐surgical excision of the transformation zone. Persistent infections with certain high‐risk human papillomavirus (hr‐HPV) genotypes play an essential role in cervical cancer carcinogenesis by mechanisms discussed in this review. HPV assessment, either DNA detection or HPV genotyping, could enhance the current cervical cancer screening programmes. Furthermore, primary prevention of cervical cancer through the introduction of HPV vaccines looks promising although the current vaccines merely protect against two hr‐HPV genotypes, leaving a niche for at least 11 other hr‐HPV's. Cervical screening in the post‐vaccination era cannot be abolished but could be altered, as discussed in this review. Algorithms with the primary objective of hr‐HPV testing followed by subjective cytology assessment in HPV‐positive women could be a solution for both pre‐ and post‐vaccination screening. Copyright © 2007 John Wiley & Sons, Ltd.
Internal layers of parabolic singularly perturbed problems
Authors: Shih S.‐D.
Published: November 2007

The aim of this work is to show, through analyzing some incorrect results in the literature, (i) the internal layer structure is not so predictable for the linear parabolic differential equations with constant coefficients; and (ii) the location of the viscous shock of Burgers' equation in the quarter plane depends on the viscosity, but not in the half plane. Our methods are based on asymptotics of integrals together with special functions to unveil these distinguished features. Contrary to the exponential function as the sole building block of boundary layer functions for differential equations and partial differential equations near the outflow boundary, the class of the complementary error function and its iterated integrals becomes fundamental in this investigation.
Source‐sink dynamics within a plant population: the impact of substrate and herbivory on palm demography
Authors: Berry Eric J. , Gorchov David L. , Endress Bryan A. , Stevens Martin Henry H.
Published: November 2007

Site factors have frequently been shown to affect survival, growth, and reproduction in plant populations. The source‐sink concept proposed by Pulliam is one way of integrating this spatial demographic variation into population models. Source‐sink models describe a population where propagules from “source” habitats sustain less productive “sink” areas. We adapted this concept to model the population dynamics of the understory palm Chamaedorea radicalis on two substrates, rock outcrops and forest floor. In our model, sources and sinks correspond to fine‐scale demographic structure within the population, rather than spatially discrete subpopulations as described in the Pulliam model. We constructed a stage‐structured population matrix model that integrates the site‐specific demography of individuals across two habitats types that are linked by migration. We then parameterized this model with field data from C. radicalis. To address whether observed differences in palm demography between rock outcrops and the forest floor were due to natural variation between microsites or due to differences in browsing intensity from free range livestock, we parameterized separate models based on the substrate‐specific demography of protected, non‐browsed palms and of palms exposed to burro browse. Results showed that herbivory reduced survival and fecundity on the forest floor, which in the absence of seed migration resulted in a projected decline of forest floor palms (sinks). However with seed dispersal, palms persisted and total population growth (both substrates) was projected to be positive, indicating that seed dispersal from non‐browsed palms on rock outcrops (sources) was sufficient to sustain C. radicalis on the forest floor.
Self‐reported prevalence, etiology, and characteristics of pain in oncology outpatients
Authors: Valeberg Berit Taraldsen , Rustøen Tone , Bjordal Kristin , Hanestad Berit Rokne , Paul Steven , Miaskowski Christine
Published: November 2007

Purpose: To determine the self‐reported prevalence rates for cancer, non‐cancer, and both cancer and non‐cancer pain and to determine if there were differences in demographic, clinical, and pain characteristics among the three pain groups.

Methods: Patients were screened in outpatient oncology clinics for the presence of pain and/or analgesic use. Patients who reported pain completed the study questionnaires.

Results: A total of 1790 patients were available for screening in the outpatient clinics and 1549 (86.5%) completed the screening questionnaire. Out of them, 332 (21.4%) reported pain or used analgesics. Of the 217 patients who completed the study questionnaires, 53% had only cancer pain (pain due to cancer and/or treatment), 25.3% had non‐cancer pain, and 21.7% had both cancer and non‐cancer pain. No differences were found, among the three pain groups, in pain intensity or pain duration. However patients in the cancer and non‐cancer pain group had higher pain interference scores, higher severity scores for various pain descriptors, and a higher number of pain locations.

Conclusions: These findings suggest that outpatients with a combination of cancer and non‐cancer pain may be at greater risk for under‐treatment of pain. Oncology clinicians and primary care providers need to perform a comprehensive pain assessment of all oncology patients in order to be able to formulate an effective pain management plan.
CarO, an Acinetobacter baumannii outer membrane protein involved in carbapenem resistance, is essential for l‐ornithine uptake
Authors: Mussi María A. , Relling Verónica M. , Limansky Adriana S. , Viale Alejandro M.
Published: November 2007

We previously associated the emergence of carbapenem resistance in Acinetobacter baumannii with the loss of an outer membrane (OM) protein designated CarO. CarO was found essential for l‐ornithine uptake: CarO‐deficient strains were specifically impaired to grow only on l‐ornithine, and failed to incorporate l‐[14C] ornithine from the medium. l‐arginine, and histidine and lysine to a lower extent, could effectively compete for l‐[14C] ornithine uptake. l‐ornithine also reduced A. baumannii sensitivity to imipenem, suggesting that both compounds compete for uptake. The overall results indicate that CarO participates in the selective uptake of l‐ornithine, carbapenems, and other basic amino acids in A. baumannii.
International Breastfeeding Initiatives and their Relevance to the Current State of Breastfeeding in the United States
Authors: Walker Marsha
Published: November 2007

Exclusive breastfeeding is becoming an endangered practice. Breastfeeding has fallen from the foundation of public health to something that is nice but not necessary in the minds of many consumers and health care professionals. Numerous international initiatives have been created to improve the initiation, duration, and exclusivity of breastfeeding throughout the world. These include the International Code of Marketing Breast‐milk Substitutes, the Innocenti Declaration, and the Baby‐Friendly Hospital Initiative. In the United States, the National Alliance for Breastfeeding Advocacy (NABA), the US Breastfeeding Committee (USBC), and Baby‐Friendly USA have played important roles in improving breastfeeding. We begin with a brief history of these initiatives and organizations and move on to discuss some of the progress and programs that can help return breastfeeding to its rightful place as the initial and most basic act of health protection.
Review of Atom Probe FIB-Based Specimen Preparation Methods
Authors: Miller Michael K. , Russell Kaye F. , Thompson Keith , Alvis Roger , Larson David J.
Published: November 2007

Several FIB-based methods that have been developed to fabricate needle-shaped atom probe specimens from a variety of specimen geometries, and site-specific regions are reviewed. These methods have enabled electronic device structures to be characterized. The atom probe may be used to quantify the level and range of gallium implantation and has demonstrated that the use of low accelerating voltages during the final stages of milling can dramatically reduce the extent of gallium implantation.
Advances in Pulsed-Laser Atom Probe: Instrument and Specimen Design for Optimum Performance
Authors: Bunton Joseph H. , Olson Jesse D. , Lenz Daniel R. , Kelly Thomas F.
Published: November 2007

The performance of the pulsed-laser atom probe can be limited by both instrument and specimen factors. The experiments described in this article were designed to identify these factors so as to provide direction for further instrument and specimen development. Good agreement between voltage-pulsed and laser-pulsed data is found when the effective pulse fraction is less than 0.2 for pulsed-laser mode. Under the conditions reported in this article, the thermal tails of the peaks in the mass spectra did not show any significant change when produced with either a 10-ps or a 120-fs pulsed-laser source. Mass resolving power generally improves as the laser spot size and laser wavelength are decreased and as the specimen tip radius, specimen taper angle, and thermal diffusivity of the specimen material are increased. However, it is shown that two of the materials used in this study, aluminum and stainless steel, depend on these factors differently. A one-dimensional heat flow model is explored to explain these differences. The model correctly predicts the behavior of the aluminum samples, but breaks down for the stainless steel samples when the tip radius is large. A more accurate three-dimensional model is needed to overcome these discrepancies.
Snowball versus slushball Earth: Dynamic versus nondynamic sea ice?
Authors: Lewis J. P. , Weaver A. J. , Eby M.
Published: November 2007

Modeling studies of the Neoproterozoic snowball Earth offer two variations for snowball conditions, the original “hard” snowball Earth where the ocean is completely covered by sea ice, and an alternate slushball Earth or “soft” snowball, where there is an equatorial oasis of open water. We use the University of Victoria Earth System Climate Model to show that the soft snowball result is only possible when dynamics are excluded from the sea ice component of the model. Using a purely thermodynamic sea ice component the soft snowball condition is stable, whereas with a dynamic and thermodynamic sea ice component it is not. As the behavior of dynamic sea ice largely depends on wind stress, we compare simulations using two different wind fields: a zonally averaged present‐day wind field and a wind field derived by a general circulation model, the Fast Ocean Atmosphere Model, using Neoproterozoic conditions. Another consequence of using dynamic sea ice is that the sea ice does not become sufficiently thick to flow under its own weight when there is open water; this suggests that sea glacier dynamics are not important for snowball inception.
Predictability: Recent insights from information theory
Authors: DelSole Timothy , Tippett Michael K.
Published: November 2007

This paper summarizes a framework for investigating predictability based on information theory. This framework connects and unifies a wide variety of statistical methods traditionally used in predictability analysis, including linear regression, canonical correlation analysis, singular value decomposition, discriminant analysis, and data assimilation. Central to this framework is a procedure called predictable component analysis (PrCA). PrCA optimally decomposes variables by predictability, just as principal component analysis optimally decomposes variables by variance. For normal distributions the same predictable components are obtained whether one optimizes predictive information, the dispersion part of relative entropy, mutual information, Mahalanobis error, average signal to noise ratio, normalized mean square error, or anomaly correlation. For joint normal distributions, PrCA is equivalent to canonical correlation analysis between forecast and observations. The regression operator that maps observations to forecasts plays an important role in this framework, with the left singular vectors of this operator being the predictable components and the singular values being the canonical correlations. This correspondence between predictable components and singular vectors occurs only if the singular vectors are computed using Mahalanobis norms, a result that sheds light on the role of norms in predictability. In linear stochastic models the forcing that minimizes predictability is the one that renders the “whitened” dynamical operator normal. This condition for minimum predictability is invariant to linear transformation and is equivalent to detailed balance. The framework also inspires some new approaches to accounting for deficiencies of forecast models and estimating distributions from finite samples.
ROCSAT observations of topside ionospheric undulations and irregularities at low to middle latitudes
Authors: Su S.‐Y. , Tsunoda R. T. , Liu C. H. , Chao C. K. , Wu J. M.
Published: November 2007

Starting from 0415 UT on 8 January 2000, ROCSAT‐1 observed intermediate‐scale (0.1 to 50 km) ion density irregularities in conjunction with mesoscale (∼50 to 1000 km) density and flow undulations in a total of eight consecutive orbits from low to middle latitudes in the northern hemisphere of nightside topside ionosphere. The mesoscale undulation indicates in‐phase variation between the outward as well as westward flow and the density enhancement. The induced electric fields derived from the flow perturbations point along the northeast–southwest direction. The locations of the disturbances mapped from the onset of each mesoscale undulation event observed in eight consecutive ROCSAT orbits form a frontal structure that is aligned from northwest to southeast. These disturbances cover a large geographic area from 120° to 300° in longitude and from latitude 20° up to the ROCSAT turn‐around latitude at 35° in the nightside ionosphere. Since the first onset of mesoscale undulations is preceded by a sudden enhancement of the background flow in the southeast direction, which can be induced by a southwest‐pointed electric field, the cause of mesoscale undulations is identified as the Perkins instability. On the other hand, it is difficult to explain the occurrence of intermediate‐scale irregularities that either appear alone in time and space, or coexist with mesoscale undulations. The signature of intermediate‐scale irregularities, in addition to the density fluctuations, is the existence of a dominant zonal flow fluctuation that is completely different from the characteristics of mesoscale undulations. One possible explanation for the existence of intermediate‐scale irregularities is from the mapping of irregularity structures from E region or lower F region. However, theoretical model for the production and mapping process of intermediate‐scale irregularity is not available at the moment. As the in situ observation of midlatitude irregularities is quite rare, we hope that the unique and distinctive properties of midlatitude irregularities, at mesoscale and intermediate scale, presented here will stimulate future theoretical study of midlatitude irregularities.
Solar activity dependence of the electron density in the equatorial anomaly regions observed by CHAMP
Authors: Liu Huixin , Stolle Claudia , Förster Matthias , Watanabe Shigeto
Published: November 2007

We have investigated the solar activity dependence of the electron density at equatorial and low latitudes using 6 years (a) of measurements between 1 August 2000 and 1 August 2006 from CHAMP and compared it with the international reference ionosphere (IRI) model. The solar activity dependence observed by CHAMP at 400 km altitude exhibits significant variation with latitude, season, and local time. First, the electron density in the crest regions of the equatorial ionization anomaly (EIA) grows roughly linearly from solar minimum to solar maximum, with a higher growth rate than that in the EIA trough region. Second, the solar activity dependence in the EIA crest regions varies strongly with season. The growth rate of the electron density with increasing solar activity around equinoxes is about 1.5 to 2 times greater than that near solstices. Third, the solar activity dependence of the EIA structure varies significantly with local time. In the noon sector the crest‐to‐trough ratio (CTR) obtained at 400 km altitude varies within only a small range between 1.14 and 1.43 from solar minimum to solar maximum. In the postsunset local time sector, however, the CTR grows remarkably with solar activity level, reaching values of above 3.9 at solar maximum. These differences are attributed to the different solar activity dependence of the vertical plasma drift in corresponding local time sectors. The IRI model was found to reproduce the equatorial electron density well near 400 km in the noon sector at all solar activity levels. However, it significantly overestimates it in the postsunset to premidnight sector at high solar activity levels. The major cause for this overestimation has been found to be the IRI's inadequate representation of the F2 layer maximum height (hmF2) in this sector, while the IRI's lack of equatorial spread F seems to play only a minor role.
Normal proportion and expression of maturation markers in migratory dendritic cells in the absence of germs or Toll‐like receptor signaling
Authors: Wilson Nicholas S , Young Louise J , Kupresanin Fiona , Naik Shalin H , Vremec David , Heath William R , Akira Shizuo , Shortman Ken , Boyle Jeff , Maraskovsky Eugene , Belz Gabrielle T , Villadangos José A
Published: November 2007

Dendritic cells (DCs) play major roles in immunosurveillance. In peripheral tissues, ‘immature’ DCs are dedicated to capturing antigens. Detection of pathogens through Toll‐like receptors (TLRs) triggers DC migration to the lymph nodes (LNs), where they acquire a ‘mature’ phenotype specialized at presenting antigens. However, DCs migrate from tissues and mature even in the absence of overt infections. This has been attributed to detection of commensal flora in the skin, the gut or other peripheral tissues in the steady state. To test this assumption, we have analyzed the DCs contained in the lymphoid organs of germ‐free mice and of mice lacking the TLR adapter molecules, MyD88 and TRIF. We show that the proportion and expression of maturation markers in DC immigrants in the LNs of these mice are similar to those in normal mice. These results suggest that DC migration from tissues, followed by their phenotypic maturation, is regulated in the steady state by an inherent program of DC differentiation or by the release of low levels of inflammatory signals from normal tissues.
What do we know about the mechanisms of elimination of autoreactive T and B cells and what challenges remain
Authors: Strasser Andreas , Puthalakath Hamsa , O'Reilly Lorraine A , Bouillet Philippe
Published: November 2007

Tolerance to self‐antigens within the adaptive immune system is safeguarded, at least in part, through deletion of autoreactive T and B lymphocytes. This deletion can occur during the development of these cells in primary lymphoid organs, the thymus or bone marrow, respectively, or at the mature stage in peripheral lymphoid tissues. Deletion of autoreactive lymphocytes is achieved to a large extent through apoptotic cell death. This review describes current understanding of the mechanisms that mediate apoptosis of autoreactive lymphocytes during their development in primary lymphoid organs and during their activation in the periphery. In particular, we discuss the roles of the proapoptotic Bcl‐2 family member Bim and the small family of Nur77‐related transcriptional regulators in lymphocyte negative selection. Finally, we speculate on the processes that may lead to the activation of Bim when antigen receptors are activated on autoreactive T or B cells.
Small‐scale immunopurification of cytochrome c oxidase for a high‐throughput multiplexing analysis of enzyme activity and amount
Authors: Murray James , Schilling Birgit , Row Richard H. , Yoo Chris B. , Gibson Bradford W. , Marusich Michael F. , Capaldi Roderick A.
Published: November 2007

COX (cytochrome c oxidase) deficiency is one of the main causes of genetic mitochondrial disease and presents with multiple phenotypes, depending on whether the causative mutation exists in a mitochondrial or nuclear gene and on whether it involves an altered catalytic or structural component or an assembly factor for this membrane‐embedded 13‐subunit enzyme complex. COX deficiency is routinely observed in AD (Alzheimer's disease), although there is continuing debate about whether this is a causative or a secondary consequence of the condition. Altered levels of COX and reduced oxidative phosphorylation capacity have been reported in other common diseases, including cancer, and are seen as unwanted side effects in a number of drug treatments, particularly with antiretroviral and antibiotic treatments. Here, we introduce a simple, rapid, high‐throughput 96‐well plate protocol that uses a multiplex approach to determine the amount and activity of COX, which should find widespread use in evaluating the above diseases and in drug safety studies. Importantly, the method uses very small amounts of cell material or tissue and does not require the isolation of mitochondria. We show the utility of this approach by example of the analysis of fibroblasts from patients with COX activity deficiency and the effect of the antiretroviral drug ddC (2′,3′‐dideoxycytidine) on the biogenesis of the enzyme.
Detection and quantification of affinity ligand leaching and specific antibody fragment concentration within chromatographic fractions using surface plasmon resonance
Authors: Thillaivinayagalingam Pranavan , Newcombe Anthony R. , O'Donovan Kieran , Francis Richard , Keshavarz‐Moore Eli
Published: November 2007

Rapid analyses of chromatographic steps within a biopharmaceutical manufacturing process are often desirable to evaluate column performance, provide mass balance data and to permit accurate calculations of yields and recoveries. Using SPR (surface plasmon resonance) biosensor (Biacore®) technology, we have developed a sandwich immunoassay to quantify polyclonal anti‐digoxin Fab fragments used for the production of the FDA (Food and Drug Administration)‐approved biotherapeutic DigiFab™. The results show that specific Fab may be quantified in all affinity process streams and accurate yield and mass balance data calculated. Control experiments using sheep Fab and Fc indicate that the assay is specific to DigiFab™. The quantification of potential leached ligand within chromatographic fractions may also be technically challenging, particularly when low‐molecular‐mass ligands are covalently coupled with an affinity absorbent. Typical methods to assess ligand leakage such as DDMA (digoxin‐dicarboxymethoxylamine; digoxin analogue) often involve the use of labelled ligands and relatively complex and labour‐intensive analytical techniques. Using the same analytical methodologies, an assay to detect leached or eluted ligand off the column was developed. The results indicate minimal levels of leached ligand in all chromatographic fractions, with total levels of leached DDMA calculated to be 1.52 μg. This is less than 0.01% of the total amount of DDMA coupled with the laboratory‐scale affinity column. The SPR methods described in the present study may be applicable for the rapid in‐process analysis of specific polyclonal Fab fragments (within a polyclonal mixture) and to rapidly assess leakage of small molecule ligands covalently attached to chromatographic supports.