bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting change with the RBANS in a community dwelling elderly
sample
Authors: DUFF KEVIN , SCHOENBERG MIKE R. , PATTON DOYLE , MOLD JAMES , SCOTT JAMES G. , ADAMS RUSSELL L.
Published: January 2005

Repeated neuropsychological assessments are common with older adults,
and the determination of clinically significant change across time is
an important issue. Regression-based prediction formulas have been
utilized with other patient and healthy control samples to predict
follow-up test performance based on initial performance and demographic
variables. Comparisons between predicted and observed follow-up
performances can assist clinicians in determining the significance of
change in the individual patient. In the current study, multiple
regression-based prediction equations for the 5 Indexes and Total Score
of the RBANS were developed for a sample of 223 community dwelling
older adults. These algorithms were then validated on a separate
elderly sample (N = 222). Minimal differences were present
between observed and predicted follow-up scores in the validation
sample, suggesting that the prediction formulas are clinically useful
for practitioners who assess older adults. A case example is presented
that illustrates how the algorithms can be used clinically.
(JINS, 2004, 10, 828–834.)
The standard error in the Jacobson and Truax Reliable Change Index:
The classical approach to the assessment of reliable change
Authors: MAASSEN GERARD H.
Published: January 2005

Researchers and clinicians using Jacobson and Truax's index to
assess the reliability of change in patients, or its counterpart by
Chelune et al., which takes practice effects into account, are confused
by the different ways of calculating the standard error encountered in
the literature (see the discussion started in this journal by
Hinton-Bayre). This article compares the characteristics of (1) the
standard error used by Jacobson and Truax, (2) the standard error of
difference scores used by Temkin et al. and (3) an adaptation of
Jacobson and Truax's approach that accounts for difference between
initial and final variance. It is theoretically demonstrated that the
last variant is preferable, which is corroborated by real data.
(JINS, 2004, 10, 888–893.)
What do Temkin's simulations of reliable change tell us?
Authors: MAASSEN GERARD H.
Published: January 2005

Due to space limitations I have chosen to confine my reply to the
comments by Temkin (this issue, pp. 899–901)
that touch most directly the concepts of practice effects and reliable
change. Temkin seems to portray my adherence to the classic approach as a
private affair. However, Temkin herself (Temkin et al.,
1999) reported to utilize the most widely applied procedures of
Jacobson and Truax and of Chelune et al., which are based on the classic
approach. For unexplained reasons they had substituted a different
standard error. The unsatisfactory justification later given in their
reply to Hinton-Bayre's (2000) letter
revealed the presumably actual reason: unfamiliarity with psychometrics
including the classical test theory (CTT). Not surprisingly, Temkin
ignores this historical aspect in her comment. Nevertheless, the new
post-hoc arguments she brings up deserve, of course, a fair
evaluation.
JINS turns 10, and the old order changeth…
Authors: Grant Igor
Published: January 2005

The year 2004 marks the 10th anniversary of the decision of the INS
governing board to establish the Journal of the International
Neuropsychological Society as its official publication. I was honored
that the governing Board selected me to be the founding editor. With my term
as Editor-in-Chief coming to a close at the end of this year, I wanted to
take this opportunity to provide our readers with a few brief reflections,
and in particular to offer my sincere appreciation to the many individuals
who have contributed to JINS' success.
Cognitive impairment in relapsing and primary progressive multiple
sclerosis: Mostly a matter of speed
Authors: DENNEY DOUGLAS R. , LYNCH SHARON G. , PARMENTER BRETT A. , HORNE NIKKI
Published: January 2005

Based on the assumption that cognitive impairment in MS is consistent
with subcortical dementia, a battery of neuropsychological tests was
assembled that included measures of executive function (Tower of London
and Wisconsin Card Sorting Test), verbal learning and memory (a paired
associates learning test), and speeded information processing (Stroop
Color Word Interference Test). The battery was administered to patients
with relapsing and primary progressive MS and to healthy controls.
Differences between patients and controls occurred on several of the
measures. However, when differences with respect to fatigue and
depression were statistically controlled, the only differences that
remained significant involved measures relating to the speed of
information processing. Patients performed more slowly than controls,
with the disparity being greater for relapsing patients than for those
with primary progressive disease. The slowing was evident on measures
of automatic as well as controlled processing and regardless of whether
speed was an explicit feature of successful performance or recorded
unobstrusively while the patient concentrated on planning a correct
solution to a problem. Parallels were noted between cognitive slowing
associated with MS and that of normal aging. (JINS, 2004,
10, 948–956.)
Speaking Clearly: Reviewing Aphasia From Assessment to Treatment:
Assessment of Aphasia. O. Spreen and A. H. Risser. 2003. New York:
Oxford University Press. 320 pp., $47.50. and Aphasia and its
Therapy. A. Basso. 2003. New York: Oxford University Press. 317 pp.,
$47.50.
Authors: Moore Anna B. , Conway Tim
Published: January 2005

Paul Broca's famous case reports of language impairment
following left hemisphere lesions were issued in the 1860s. Since that
time, much has been written about the assessment, typology, and neural
underpinnings of aphasia. The two books we had the pleasure of reading
and reviewing, Assessment of Aphasia and Aphasia and its
Therapy, present well thought out and thorough reviews of aphasia
literature, the first focusing on assessment issues, the latter
focusing more on issues of and theoretical approaches to treatment. The
books are united in their insistence that the field of aphasia
research, from assessment to rehabilitation, be grounded in theory and
a defensible conceptual model. This overarching theme presents itself
throughout the entire corpus of both texts. Just as the clinician
conducts a thorough assessment before initiating treatment, so too will
this review begin with the book focused predominantly on aphasia
assessment, before moving on to aphasia therapy.
A Factor Analytic Approach to the WAIS–III and WMS–III: Clinical Interpretation of the WAIS–III and WMS–III. D.S.
Tulsky, D.H. Saklofske, G.J. Chelune, R.K. Heaton, R.J. Ivnik, R. Bornstein,
A. Prifitera, and M.F. Ledbetter (Eds.). 2003. Amsterdam: Academic Press. 618
pp., $75.00.
Authors: Snow W. Gary
Published: January 2005

This is an edited collection of papers that focuses on various
aspects of the most recent revision of the Wechsler Adult Intelligence
Scale (WAIS–III) and Wechsler Memory Scale (WMS–III). The
papers in this volume fall into three broad areas. The first section
of the book (and part of one of the subsequent chapters) provides an
overview of the history of the development of measures of memory and
intelligence, with particular emphasis on the Wechsler scales. These
chapters are thoroughly delightful, and the only shortcoming is that
they are too brief. Indeed, though over 100 pages are devoted to this
topic, there are a number of questions about the measures which could
have been answered but weren't. (For example, given the cost and
time pressures on psychological assessment, why were the
tests—particularly the WMS–III—lengthened? Why, for
example, include a measure of list learning when Psychological
Corporation already published the California Verbal Learning Test? Why,
after all these years, hasn't the WAIS Information subtest been
dropped or the content made less specific to the United States? What
led to the decision to include a verbally mediated measure of visual
memory on the WMS–III, a decision which can make it harder to
evaluate visual memory in aphasics?) Given how involved they were in
the revisions of the WAIS and WMS, the editors would appear to have
been uniquely positioned to provide a more in-depth discussion of the
issues that arose during this process and how these issues were
resolved.
Probability and the Single Neuron: Decisions, Uncertainty and
the Brain: The Science of Neuroeconomics, by P.-W. Glimcher. 2003.
Cambridge, MA: MIT Press. 375 pp., $40.00.
Authors: Kinsbourne M.
Published: January 2005

In an uncertain world, people and other animals make their living by
predicting which of alternative courses of action is likely to yield
the best return. For humans the return might take many forms, such as
material, financial, social, or esthetic, but the underlying currency
involved for any species is “inclusive fitness,” the rate
at which an animal's genes are propagated. Professor Glimcher
demonstrates that Economics methods are applicable to decision-making
under conditions of uncertainty, both at the behavioral and the
neuronal level. This approach has been called neuro-economics, although
“econometrics” characterizes it more precisely.
Econometrics is the application of statistical and mathematical methods
in the field of economics to test and quantify economic theories and
the solution to economic problems. Specifically, individuals'
decision-making benefits from knowing how likely a response is to be
reinforced, and knowing the reinforcement's value. Even single
neurons are sensitive to these variables. Glimcher reaches beyond the
heavily studied neural substrate for sensation and response to
predictive neural circuitry that factors in the prior probability of
reward, and its expected value. Indeed, he and his colleagues have
identified neurons in monkey's inferior parietal lobule whose
firing rates reflect both probability and value.
Martian dust devils: Directions of movement inferred from their tracks
Authors: Greeley Ronald , Whelley Patrick L. , Neakrase Lynn D. V.
Published: January 2005

Active dust devils (atmospheric vortices with entrained dust) seen on Mars leave surface tracks inferred to result from the injection of loose particles into the atmosphere, typically exposing a darker (or, in some cases brighter) substrate. Hundreds of similar appearing surface tracks are common in many areas, but in the absence of imaging the active dust devils responsible for their formation, it has not been possible to determine the direction of forward motion of the vortex. Laboratory experiments simulating dust devils show that overlapping scallops in some tracks enable the direction of forward motion to be determined.
The effect of soil hydraulic properties vs. soil texture in land surface models
Authors: Gutmann E. D. , Small E. E.
Published: January 2005

Proper selection of parameters for a land surface model is critical, but is difficult due to the lack of data and difficulties in scaling existing data. In particular, the spatial distribution of Soil Hydraulic Properties (SHPs) is not well known. This study focuses on the effect of SHP selection on modeled surface fluxes following a rain storm in a semi‐arid environment. SHPs are often defined based on a Soil Texture Class (STC). To examine the effectiveness of this approach, we run the Noah land surface model with each of 1306 soils in a large SHP database. Within most STCs, the outputs have a range of 350 Wm−2 for latent and sensible heat fluxes, and 8K for surface temperature. The average difference between STC median values is only 100 Wm−2 for latent and sensible heat. STC explains 5–15% of the variance in model outputs and should not be used to determine SHPs.
Observations of the O(3P) fine structure line at 63 μm in the upper mesosphere and lower thermosphere
Authors: Mlynczak Martin G. , Martin‐Torres F. Javier , Johnson David G. , Kratz David P. , Traub Wesley A. , Jucks Ken
Published: January 2005

Observations of the O(3P) fine structure line at 63 μm originating in the upper mesosphere and lower thermosphere have been obtained by the far‐infrared spectrometer (FIRS‐2) instrument, a Fourier transform spectrometer that flies periodically on high‐altitude balloons. FIRS‐2 primarily observes stratospheric ozone photochemistry using the technique of limb emission spectroscopy. As part of the routine operation of FIRS‐2, up‐looking views are made, during which the emission from the atomic oxygen is recorded. Using the Mass Spectrometer Incoherent Scatter (MSIS) empirical model to provide temperature and atomic oxygen concentrations, we compute radiances for comparison with the FIRS‐2 observations. The computed radiances agree with the FIRS‐2 measurements, which encompass 31 observations during nine flights over a span of 14 years, to within 10% on average, with 23 of the 31 observations agreeing to within measurement and calculation uncertainty. The consistency between the observed and computed radiances suggests that the MSIS model provides a reasonably accurate representation of temperature and atomic oxygen in the upper mesosphere and lower thermosphere.
Dynamic damage model of crevasse opening and application to glacier calving
Authors: Pralong A. , Funk M.
Published: January 2005

Theory and applications of continuum damage mechanics for ice are discussed, and on this basis, an ice damage model, valid at low stresses, is proposed. The model describes the damage itself, the rheology of the damaged ice, and the damage evolution. A local damaging and healing law is considered, and its parameterization is motivated. The model parameters are inferred from published data of laboratory experiments. The model is subsequently implemented in a finite element code and applied to the prediction of a calving process and to the destabilization of an ice chunk from a hanging glacier. Numerical results show good agreement with field measurements.
Assessing the ability of first‐order reversal curve (FORC) diagrams to unravel complex magnetic signals
Authors: Muxworthy Adrian R. , King James G. , Heslop David
Published: January 2005

First‐order reversal curve (FORC) diagrams for mixtures of different magnetic phases and bimodal distributions have been measured to examine the efficiency of the FORC method at unraveling complex magnetic signals. The FORC distributions for various magnetic minerals, including magnetite, maghemite, hematite, and goethite, and their linear additivity are assessed. Mixtures containing only hard magnetic minerals like hematite or goethite, which have relatively small spontaneous magnetizations (MS) and large magnetocrystalline anisotropies, can be adequately described by a linear addition of the two end‐members, because there are virtually no magnetostatic interactions between the phases. Mixtures dominated by softer minerals like magnetite and maghemite are more susceptible to interactions and exhibit nonlinear behavior. When a hard phase with low MS like hematite is mixed with a softer phase with high MS like magnetite, it can still be identified using the FORC technique, whereas it is impossible to do so using standard magnetic hysteresis measurements. When the weaker phase can be identified, then weak‐strong mixes add linearly; however, beyond a certain critical concentration the mineral with high MS swamps the magnetic signal and linearity breaks down. It is suggested that the FORC method is highly suitable for identifying small traces of hard magnetic minerals like hematite and goethite in the presence of minerals with high MS such as magnetite.
Assessing the ability of numerical ice sheet models to simulate grounding line migration
Authors: Vieli A. , Payne A. J.
Published: January 2005

Grounding line migration is a key process affecting the stability of marine ice sheets such as the West Antarctic ice sheet (WAIS). Grounding line motion is often included in numerical models simulating the past and future evolution of the WAIS; however, little attention has been paid to the numerical consistency of these models. The aim of this paper is to assess the ability of simple versions of existing marine ice sheet models to simulate grounding line migration. In particular, we investigate the response of the grounding line to external forcing and the sensitivity of the models' predictions to their numerics and the mechanical coupling between ice sheet and shelf. From the model comparison, there is no consensus on how the grounding line should react to changes in boundary conditions. A crucial finding is the strong dependency of models using a fixed grid on numerical details such as the horizontal grid size. This implies that we should be very wary about grounding line predictions from such models. Including mechanical coupling at the grounding line does not seem to change the qualitative behavior of the models. This suggests that the way the grounding line is treated in marine ice sheet models dominantly determines the grounding line dynamics. We find that models that employ a moving grid to explicitly track the grounding line do not share many of the deficiencies of the fixed grid models. We conclude that at present, no reliable model of the grounding line is available, and further model development is urgently needed.
Time-resolved intraband electronic relaxation dynamics of Hgn− clusters (n=7–13,15,18) excited at 1.0 eV
Authors: Bragg Arthur E. , Verlet Jan R. R. , Kammrath Aster , Cheshnovsky Ori , Neumark Daniel M.
Published: January 2005

Time-resolved photoelectron imaging has been used to study the relaxation dynamics of small Hgn− clusters (n=7–13,15,18) following intraband electronic excitation at 1250 nm (1.0 eV). This study furthers our previous investigation of single electron, intraband relaxation dynamics in Hgn− clusters at 790 nm by exploring the dynamics of smaller clusters (n=7–10), as well as those of larger clusters (n=11–13,15,18) at a lower excitation energy. We measure relaxation time scales of 2–9 ps, two to three times faster than seen previously after 790 nm excitation of Hgn−, n=11–18. These results, along with size-dependent trends in the absorption cross-section and photoelectron angular distribution anisotropy, suggest significant evolution of the cluster anion electronic structure in the size range studied here. Furthermore, the smallest clusters studied here exhibit 35–45 cm−1 oscillations in pump-probe signal at earliest temporal delays that are interpreted as early coherent nuclear motion on the excited potential energy surfaces of these clusters. Evidence for evaporation of one or two Hg atoms is seen on a time scale of tens of picoseconds.
Pd ∕ H system in H2 plasmas
Authors: Di Pascasio F. , Gozzi D. , Panella B. , Trionfetti C.
Published: January 2005

The absorption of hydrogen by Pd wire samples has been studied at 299 K and in the H2 pressure range from 18 to 1800 mbar under both tensile stress and tensile stress under cold H2 plasma. Plasma is generated in a corona discharge regime by applying a dc high voltage between a Pd wire and a cylindrical counterelectrode. Positive and negative coronas have been performed. Three independent experimental quantities have been simultaneously measured: ratio x=nH∕nPd, with n the number of atoms; ratio R∕R0, with R the four-probe resistance of the wire and R0 the resistance when x=0; and ratio Δl∕l0, with Δl the length change of the wire and l0 its length when x=0. From the thermodynamic analysis of data, the absorption standard chemical potential, Δμabs0, and the excess chemical potential, Δμexc, of hydrogen atoms in Pd have been obtained. At constant T,H2 pressure, and tensile stress, the x value under cold plasma is always higher.
Nanoarchitectures of semiconducting and piezoelectric zinc oxide
Authors: Gao Pu Xian , Wang Zhong L.
Published: January 2005

Semiconducting and piezoelectric zinc oxide has two important structure characteristics: the multiple and switchable growth directions: ⟨011¯0⟩, ⟨21¯1¯0⟩, and ⟨0001⟩; and the {0001} polar surfaces. The fast growth directions create nanobelts of different crystallographic facets, and the polar surfaces result in bending of the nanobelt for minimizing the spontaneous polarization energy. A combination of these distinct growth characteristics results in a group of unique nanostructures, including several types of nanorings, nanobows, platelet circular structures, Y-shape split ribbons, and crossed ribbons. We present here the as-grown nanoarchitectures naturally created by combining some of the fundamental structure configurations of ZnO, which could be unique for many applications in nanotechnology.
Receptor editing in peripheral B cell tolerance
Authors: Rice Jeffrey S. , Newman Jeffrey , Wang Chuansheng , Michael Daniel J. , Diamond Betty
Published: January 2005

Receptor editing or secondary Ig gene rearrangement occurs in immature, autoreactive B cells to maintain self-tolerance. Here we show that nonspontaneously autoimmune mice immunized with a peptide mimetope of DNA develop peptide- and DNA-reactive antibodies. Antigen-specific B cells display a follicular B cell phenotype. As these cells move into the memory compartment, many express RAG protein and acquire expression of both κ and λ light chains. Thus, this study provides evidence for receptor editing occurring in a mature, antigen-activated B cell population. Because the receptor editing observed here occurred in an autoreactive response to antigen, it may function to maintain peripheral tolerance.
The Abl/Arg substrate ArgBP2/nArgBP2 coordinates the function of multiple regulatory mechanisms converging on the actin cytoskeleton
Authors: Cestra Gianluca , Toomre Derek , Chang Sunghoe , De Camilli Pietro
Published: January 2005

ArgBP2, and its brain-specific splice variant, nArgBP2, are interactors and substrates of Abl/Arg tyrosine kinases and of the ubiquitin ligase Cbl. They are members of a family of adaptor proteins that colocalize with actin on stress fibers and at cell-adhesion sites, including neuronal synapses. We show here that their NH
2
-terminal region, which contains a sorbin homology domain domain, interacts with spectrin, and we identify binding proteins for their COOH-terminal SH3 domains. All these binding partners participate in the regulation of the actin cytoskeleton. These include dynamin, synaptojanin, and WAVE isoforms, as well as WAVE regulatory proteins. At least two of the ArgBP2/nArgBP2 binding partners, synaptojanin 2B and WAVE2, undergo ubiquitination and Abl-dependent tyrosine phosphorylation. ArgBP2/nArgBP2 knockdown in astrocytes produces a redistribution of focal adhesion proteins and an increase in peripheral actin ruffles, whereas nArgBP2 overexpression produces a collapse of the actin cytoskeleton. Thus, ArgBP2/nArgBP2 is a scaffold protein that control the balance between adhesion and motility by coordinating the function of multiple signaling pathways converging on the actin cytoskeleton.
Inhibition of cardiac lipoprotein utilization by transgenic overexpression of Angptl4 in the heart
Authors: Yu Xinxin , Burgess Shawn C. , Ge Hongfei , Wong Kenny K. , Nassem R. Haris , Garry Daniel J. , Sherry A. Dean , Malloy Craig R. , Berger Joel P. , Li Cai
Published: January 2005

To investigate the role of Angptl4, an inhibitor of lipoprotein lipase that is induced by >3-fold in the heart after rosiglitazone treatment, we generated transgenic mice that overexpress Angptl4 in the heart (MHC-Angptl4). We show that MHC-Angptl4 mice exhibit cardiac-restricted expression of the transgene and inhibition of cardiac lipoprotein lipase (LPL) activity. However, LPL activities in other tissues or that released into plasma by heparin are not affected. In addition, MHC-Angptl4 mice also exhibit hypertriglyceridemia after 6 h of fasting. We use echocardiography to show that MHC-Angptl4 mice develop left-ventricular dysfunction. Comparison of the metabolic profiles of isolated working hearts demonstrates that cardiac impairment in MHC-Angptl4 mice is positively associated with decreased triglyceride (TG) utilization. When bred to transgenic mice that overexpress acyl-CoA synthetase in the heart, a strain that exhibits elevated cardiac TG accumulation, cardiac TG content in double transgenic mice is reversed to that of wild-type mice. Taken together, our data support the hypothesis that induction of Angptl4 in the heart inhibits lipoprotein-derived fatty acid delivery. This mouse model will be useful to elucidate the role of reduced fatty acid supply in the pathogenesis of heart failure and related disorders.
Making clot angioplasty safer in hyperacute stroke
Authors: Goyal M. , Srinivasan A. , Lum C.
Published: January 2005

We describe a technique for performing clot angioplasty using a single lumen balloon catheter for thrombolytic administration, check injections of the distal circulation and for angioplasty. We believe this reduces both the time of the procedure and the risk of vessel rupture.
Carotid and brachial intima-media thickness, arterial diameter and resistivity indices in aortic regurgitation
Authors: Kervancioglu S. , Davutoglu V. , Ozkur A. , Sezen Y. , Kervancioglu R. , Bayram M. M.
Published: January 2005

Purpose: To evaluate signs of atherosclerosis in carotid and brachial arteries in patients with aortic regurgitation (AR).

Material and Methods: The sonograms of 33 patients (24 M and 9 F, 16-67 years old) with pure AR and 20 control subjects (15 M and 5 F, 19-49 years old) were evaluated. Patients with AR and control subjects completed a questionnaire with SMART risk score based on pre-existing vascular disease and risk factors. AR patients and control subjects were assessed for intima-media thickness (IMT) of common carotid artery (CCA), IMT of brachial artery (BA), CCA diameter, and resistivity index (RI) of CCA and RI of internal carotid artery (ICA).

Results: There was no significant difference in the cardiovascular risk score between the patients with AR and control subjects. All measured parameters were statistically significantly greater in AR patients than in control subjects with P values 0.0233 for CCA IMT, 0.0034 for BA IMT, 0.0429 for CCA diameter, <0.0001 for CCA RI, and 0.0002 for ICA RI.

Conclusion: AR is associated with signs generally considered to represent atherosclerosis, such as increased CCA and BA IMT, CCA diameter, and CCA and ICA RI.
A Novel GTPase-activating Protein for ARF6 Directly Interacts with Clathrin and Regulates Clathrin-dependent Endocytosis
Authors: Tanabe Kenji , Torii Tetsuo , Natsume Waka , Braesch-Andersen Sten , Watanabe Toshio , Satake Masanobu
Published: January 2005

ADP-ribosylation factor 6 (Arf6) is a small-GTPase that regulates the membrane trafficking between the plasma membrane and endosome. It is also involved in the reorganization of the actin cytoskeleton. GTPase-activating protein (GAP) is a critical regulator of Arf function as it inactivates Arf. Here, we identified a novel species of GAP denoted as SMAP1 that preferentially acts on Arf6. Although overexpression of SMAP1 did not alter the subcellular distribution of the actin cytoskeleton, it did block the endocytosis of transferrin receptors. Knock down of endogenous SMAP1 also abolished transferrin internalization, which confirms that SMAP1 is needed for this endocytic process. SMAP1 overexpression had no effect on clathrin-independent endocytosis, however. Intriguingly, SMAP1 binds directly to the clathrin heavy chain via its clathrin-box and mutation studies revealed that its GAP domain and clathrin-box both contribute to the role SMAP1 plays in clathrin-dependent endocytosis. These observations suggest that SMAP1 may be an Arf6GAP that specifically regulates one of the multiple functions of Arf6, namely, clathrin-dependent endocytosis, and that it does so by binding directly to clathrin.
Fission Yeast mto2p Regulates Microtubule Nucleation by the Centrosomin-related Protein mto1p
Authors: Samejima Itaru , Lourenço Paula C. C. , Snaith Hilary A. , Sawin Kenneth E.
Published: January 2005

From an insertional mutagenesis screen, we isolated a novel gene, mto2+, involved in microtubule organization in fission yeast. mto2Δ strains are viable but exhibit defects in interphase microtubule nucleation and in formation of the postanaphase microtubule array at the end of mitosis. The mto2Δ defects represent a subset of the defects displayed by cells deleted for mto1+ (also known as mod20+ and mbo1+), a centrosomin-related protein required to recruit the γ-tubulin complex to cytoplasmic microtubule-organizing centers (MTOCs). We show that mto2p colocalizes with mto1p at MTOCs throughout the cell cycle and that mto1p and mto2p coimmunoprecipitate from cytoplasmic extracts. In vitro studies suggest that mto2p binds directly to mto1p. In mto2Δ mutants, although some aspects of mto1p localization are perturbed, mto1p can still localize to spindle pole bodies and the cell division site and to “satellite” particles on interphase microtubules. In mto1Δ mutants, localization of mto2p to all of these MTOCs is strongly reduced or absent. We also find that in mto2Δ mutants, cytoplasmic forms of the γ-tubulin complex are mislocalized, and the γ-tubulin complex no longer coimmunoprecipitates with mto1p from cell extracts. These experiments establish mto2p as a major regulator of mto1p-mediated microtubule nucleation by the γ-tubulin complex.
The Dof Transcription Factor OBP3 Modulates Phytochrome and Cryptochrome Signaling in Arabidopsis
Authors: Ward Jason M. , Cufr Carie A. , Denzel Megan A. , Neff Michael M.
Published: January 2005

Plants perceive subtle changes in light quality and quantity through a set of photoreceptors, including phytochromes and cryptochromes. Upon perception, these photoreceptors initiate signal transduction pathways leading to photomorphogenic changes in development. Using activation-tagging mutagenesis to identify novel light-signaling components, we have isolated a gain-of-function mutant, sob1-D (suppressor of phytochrome B-4 [phyB-4] dominant), which suppresses the long-hypocotyl phenotype of the phyB missense allele, phyB-4. The sob1-D mutant phenotype is caused by the overexpression of a Dof (DNA binding with one finger) transcription factor, OBF4 Binding Protein 3 (OBP3). A translational fusion between OBP3 and green fluorescent protein is nuclear localized in onion (Allium cepa) cells. Tissue-specific accumulation of an OBP3:OBP3-β-glucuronidase translational fusion is regulated by light in Arabidopsis thaliana. Hypocotyls of transgenic lines with reduced OBP3 expression are less responsive to red light. This aberrant phenotype in red light requires functional phyB, suggesting that OBP3 is a positive regulator of phyB-mediated inhibition of hypocotyl elongation. Furthermore, these partial-loss-of-function lines have larger cotyledons. This light-dependent cotyledon phenotype is most dramatic in blue light and requires functional cryptochrome 1 (cry1), indicating that OBP3 is a negative regulator of cry1-mediated cotyledon expansion. These results suggest a model where OBP3 is a component in both phyB and cry1 signaling pathways, acting as a positive and negative regulator, respectively. An alternate, though not mutually exclusive, model places OBP3 as a general inhibitor of tissue expansion with phyB and cry1, differentially modulating OBP3's role in this response.
Characterization of the Arabidopsisclb6Mutant Illustrates the Importance of Posttranscriptional Regulation of the Methyl-d-Erythritol 4-Phosphate Pathway
Authors: Guevara-García Arturo , San Román Carolina , Arroyo Analilia , Cortés María Elena , de la Luz Gutiérrez-Nava María , León Patricia
Published: January 2005

The biosynthesis of isopentenyl diphosphate and dimethylallyl diphosphate, the two building blocks for isoprenoid biosynthesis, occurs by two independent pathways in plants. The mevalonic pathway operates in the cytoplasm, and the methyl-d-erythritol 4-phosphate (MEP) pathway operates in plastids. Plastidic isoprenoids play essential roles in plant growth and development. Plants must regulate the biosynthesis of isoprenoids to fulfill metabolic requirements in specific tissues and developmental conditions. The regulatory events that modulate the plant MEP pathway are not well understood. In this article, we demonstrate that the CHLOROPLAST BIOGENESIS6 (CLB6) gene, previously shown to be required for chloroplast development, encodes 1-hydroxy-2-methyl-butenyl 4-diphosphate reductase, the last-acting enzyme of the MEP pathway. Comparative analysis of the expression levels of all MEP pathway gene transcripts and proteins in the clb6-1 mutant background revealed that posttranscriptional control modulates the levels of different proteins in this central pathway. Posttranscriptional regulation was also found during seedling development and during fosmidomycin inhibition of the pathway. Our results show that the first enzyme of the pathway, 1-deoxy-d-xylulose 5-phosphate synthase, is feedback regulated in response to the interruption of the flow of metabolites through the MEP pathway.
A Threshold Autoregressive Model for Wholesale Electricity Prices
Authors: Ricky Rambharat B. , Brockwell Anthony E. , Seppi Duane J.
Published: January 2005

We introduce a discrete time model for electricity prices which accounts for both transitory spikes and temperature effects. The model allows for different rates of mean reversion: one for weather events, one around price jumps and another for the remainder of the process. We estimate the model by using a Markov chain Monte Carlo approach with 3 years of daily data from Allegheny County, Pennsylvania. We show that our model outperforms existing stochastic jump diffusion models for this data set. Results also demonstrate the importance of model parameters corresponding to both the temperature effect and the multilevel mean reversion rate.
Reactive oxygen species mediate abnormal contractile response to sympathetic nerve stimulation and noradrenaline in the vas deferens of chronically diabetic rats: effects of in vivo treatment with antioxidants
Authors: Güneş A. , Ceylan A. , Sarıoǧlu Y. , Stefek M. , Bauer V. , Karasu Ç. ,   The Antioxidants in Diabetes‐induced Complications (ADIC) Study Group
Published: January 2005

Previous studies suggest that a link exists between increased oxidative stress and diabetic neuropathy. Moreover, antioxidants may protect neurones from the degenerative effects of reactive oxygen species. In our study, we used streptozotocin (STZ)‐diabetic rats in a 8‐month chronic diabetes model to study the effects of in vivo treatment with stobadine (ST), a pyridoindole antioxidant, and vitamin E. STZ‐diabetic rats were treated with ST (24.7 mg/kg/day), vitamin E (d,l‐alpha‐tocopheryl acetate, 400–500 IU/kg/day) or ST plus vitamin E through an intra‐oral catheter for a 8‐month period beginning 10 days after STZ injection. Blood glucose and HbA1c levels were increased in diabetic rats by about 400 and 100%, respectively. Antioxidant treatment significantly decreased haemoglobin glycosylation (P < 0.05). We also determined the effects of chronic diabetes on sympathetic neurotransmission by measuring the contractility of isolated vas deferens. Furthermore, we investigated contractions elicited by electrical field stimulation (EFS) (1–64 Hz) which were significantly decreased in diabetic rats when compared with control rats. Treatment with ST or vitamin E alone partly enhanced the amplitude of the contractions induced by EFS, but a combination of ST and vitamin E treatment showed no additional effects. Contractile response of the vas deferens to exogenous noradrenaline, was increased in diabetic rats when compared with control rats. While the addition of vitamin E alone had no effect, ST completely returned noradrenaline‐induced contractions to basal levels. The tension induced by 120 mm KCl was not statistically different among the experimental groups. In normal rats, EFS‐induced contractions were significantly inhibited by pyrogallol (10−4 m), a free‐radical generator. Percentage inhibition of pyrogallol on EFS (32 Hz)‐induced contractions in ring sections was 48 ± 5.8 in control, 75 ± 5.5 in untreated‐diabetic, 54 ± 2.7 in ST‐treated diabetic, and 58 ± 4.7 in vitamin E‐treated diabetic rats. Combining both ST and vitamin E treatment had the same effects as each antioxidant alone with a percent inhibition of 48 ± 6.8. These results are consistent with the degenerative changes seen in sympathetic nerves and the abnormal function observed in chronically diabetic rats, leading to a decrease in EFS response and an increase in response to adrenergic agonists in the vas deferens. Furthermore, we demonstrated that reactive oxygen species are responsible for impaired sympathetic neurotransmission and abnormal function of diabetic vas deferens, and that a combination of antioxidants may be better for the therapy of reproductive system disabilities in male diabetics.
Influence of exposure to electromagnetic field on the cardiovascular system
Authors: Jeong J. H. , Kim J. S. , Lee B. C. , Min Y. S. , Kim D. S. , Ryu J. S. , Soh K. S. , Seo K. M. , Sohn U. D.
Published: January 2005

1 We examined whether extremely low frequency electromagnetic fields (ELF‐EMF) affect the basal level of cardiovascular parameters and influence of drugs acting on the sympathetic nervous system.

2 Male rats were exposed to sham control and EMF (60 Hz, 20 G) for 1 (MF‐1) or 5 days (MF‐5). We evaluated the alterations of blood pressure (BP), pulse pressure (PP), heart rate (HR), and the PR interval, QRS interval and QT interval on the electrocardiogram and dysrhythmic ratio in basal level and dysrhythmia induced by β‐adrenoceptor agonists.

3 In terms of the basal levels, there were no statistically significant differences among control, MF‐1 and MF‐5 in PR interval, QRS interval, mean BP, HR and PP. However, the QT interval, representing ventricular repolarization, was significantly reduced by MF‐1 (P < 0.05).

4 (−)‐Dobutamine (β1‐adrenoceptor‐selective agonist)‐induced tachycardia was significantly suppressed by ELF‐EMF exposure in MF‐1 for the increase in HR (ΔHR), the decrease in QRS interval (ΔQRS) and the decrease in QT (ΔQT) interval. Adrenaline (nonselective β‐receptor agonist)‐induced dysrhythmia was also significantly suppressed by ELF‐EMF in MF‐1 for the number of missing beats, the dysrhythmic ratio, and the increase in BP and PP.

5 These results indicated that 1‐day exposure to ELF‐EMF (60 Hz, 20 G) could suppress the increase in HR by affecting ventricular repolarization and may have a down‐regulatory effect on responses of the cardiovascular system induced by sympathetic agonists.
Is cyclic AMP formation desensitized in patients with end‐stage renal failure?
Authors: Leineweber K. , Schwiebert C. , Büscher R. , Michel M. C.
Published: January 2005

1 Cyclic AMP formation has consistently been reported to be desensitized in various tissues including heart of animal models of end‐stage renal failure (ESRF). In contrast, reports on desensitization of cAMP formation in ESRF patients remain contradictory. Whether this discrepancy results from a difference between human ESRF and its animal models or from the use of circulating blood cells in the human and various solid tissues in the animal studies, remains unclear. Therefore, we performed three studies with heart and platelets of ESRF patients undergoing haemodialysis or continuous ambulatory peritoneal dialysis and age‐ and gender‐matched controls with normal renal function (n = 11–13 each).

2 In platelets from haemodialysis patients adenylyl cyclase activity in response to receptor‐dependent and ‐independent agonists was reduced by ≈30%, and this could be explained by an alteration at the level of adenylyl cyclase itself. However, no such desensitization was seen in platelets from peritoneal dialysis patients.

3 In hearts from ESRF patients undergoing haemodialysis, β‐adrenoceptor density and subtype distribution, cAMP formation in response to the β‐adrenoceptor agonist isoprenaline or various receptor‐independent stimuli, were very similar to those in control patients but activity of G‐protein‐coupled receptor kinase was increased by ≈20%.

4 We conclude that conflicting reports on the desensitization of cAMP formation between ESRF patients and ESRF animal models are not explained by the use of solid tissues in animal studies vs. circulating blood cells in patient studies. Rather desensitization of cAMP formation seems to be a less consistent feature of human ESRF than of its animal models.
Numerical and functional responses of breeding passerine species to mass occurrence of geometrid caterpillars in a subalpine birch forest: a 30‐year study
Authors: HOGSTAD OLAV
Published: January 2005

In northern Fennoscandia, the geometrid moths Epirrita autumnata and Operophtera brumata have cyclicities in density with mass occurrence at 10‐year intervals. The larvae of Epirrita and Operophtera attain a size of 2–3 cm and 1.5–2 cm, respectively, and are nutritious food items for passerine birds. To examine whether these larvae have any numerical and/or functional influence on a passerine bird community (mountain birch forest in Budal, central Norway) during a 30‐year period (1972–2001), I estimated their abundance (number of larvae per 100 sweeps) in the birch canopy, and the densities of breeding birds in the passerine community. In addition, from 1972 to 1998, I monitored the nesting success of five of the bird species. The foraging pattern of the most abundant bird species and their gizzard contents (adults and nestlings) were examined in 1972–78 (covering population peaks of both the geometrids). Population peaks of Epirrita occurred in 1975–76, 1985–86 and 1996, and of Operophtera in 1976–77, 1986–87 and 1997–98. The passerine community consisted of eight species that were territorial in all 30 years, one species in 26 years, three species in 14–21 years and three species in 1–4 years. Only the Brambling Fringilla montifringilla population responded numerically to the fluctuations of Epirrita and Operophtera. Brambling was also the only species whose mean clutch size varied between years, and this correlated positively with the density of Epirrita. The mean annual nesting success of Willow Warbler Phylloscopus trochilus, Bluethroat Luscinia svecica and Common Redpoll Carduelis flammea tended to be higher in years with mass outbreaks of Epirrita, but was significantly so only for Reed Bunting Emberiza schoeniclus. The abundance of Operophtera larvae showed no influence on the nesting success of any bird species. The passerines foraged more frequently in the birch canopy in the Epirrita outbreak years (1975–76) than in the years before or after. Gizzard analyses of five adult passerine species and their nestlings showed that Epirrita was the main food item in 1974–76. Even though Operophtera occurred in large numbers in birch trees in 1976 and 1977, only a few larvae were found in the gizzards of the passerines. None of the passerines showed an increase in their population density in the year following the larval outbreaks, but the densities of Willow Warbler and Bluethroat increased in the succeeding year, indicating a higher return rate for these species. The study shows the existence of a dietary response and also indicates a reproductive response to the changes in the abundance of Epirrita in mountain birch forest. The lack of numerical response in the passerines (except the Brambling) to the fluctuation in Epirrita contrasts with the pattern described for passerine communities in northern temperate deciduous forests in North America, where Lepidoptera caterpillars periodically have mass outbreaks.
Proficient incubation by inexperienced Savannah Sparrows Passerculus sandwichensis
Authors: WHEELWRIGHT NATHANIEL T. , BEAGLEY JANET C.
Published: January 2005

We compared the incubation behaviour of 1‐year‐old female Savannah Sparrows Passerculus sandwichensis nesting for the first time with that of older females that had nested in previous years on Kent Island, New Brunswick, Canada. Using temperature probes inserted into 32 nests, we determined the length and variability of incubation shifts and recesses over 99 nest‐days. At 14 of the nests, known‐age females were matched, each pair consisting of an inexperienced yearling and an experienced older female, and nest temperatures were measured simultaneously. In addition, we quantified the duration of night‐time incubation and the mean length and variation of more than 1350 incubation shifts and recesses as a function of female age, weather, time of day and date. In all respects, yearling and older females had equivalent incubation behaviour. The similarity between yearlings and older females suggests that fundamental aspects of incubation behaviour may be largely innate and unaffected by prior reproductive experience or other age‐related variables.
T Helper Cell Fate Specified by Kinase-Mediated Interaction of T-bet with GATA-3
Authors: Hwang Eun Sook , Szabo Susanne J. , Schwartzberg Pamela L. , Glimcher Laurie H.
Published: January 2005

Cell lineage specification depends on both gene activation and gene silencing, and in the differentiation of T helper progenitors to Th1 or Th2 effector cells, this requires the action of two opposing transcription factors, T-bet and GATA-3. T-bet is essential for the development of Th1 cells, and GATA-3 performs an equivalent role in Th2 development. We report that T-bet represses Th2 lineage commitment through tyrosine kinase–mediated interaction between the two transcription factors that interferes with the binding of GATA-3 to its target DNA. These results provide a novel function for tyrosine phosphorylation of a transcription factor in specifying alternate fates of a common progenitor cell.
Charging Effects on Bonding and Catalyzed Oxidation of CO on Au
8
Clusters on MgO
Authors: Yoon Bokwon , Häkkinen Hannu , Landman Uzi , Wörz Anke S. , Antonietti Jean-Marie , Abbet Stéphane , Judai Ken , Heiz Ueli
Published: January 2005

Gold octamers (Au
8
) bound to oxygen-vacancy F-center defects on Mg(001) are the smallest clusters to catalyze the low-temperature oxidation of CO to CO
2
, whereas clusters deposited on close-to-perfect magnesia surfaces remain chemically inert. Charging of the supported clusters plays a key role in promoting their chemical activity. Infrared measurements of the stretch vibration of CO adsorbed on mass-selected gold octamers soft-landed on MgO(001) with coadsorbed O
2
show a red shift on an F-center–rich surface with respect to the perfect surface. The experiments agree with quantum ab initio calculations that predict that a red shift of the C–O vibration should arise via electron back-donation to the CO antibonding orbital.
Electron Spectroscopy of Aqueous Solution Interfaces Reveals Surface Enhancement of Halides
Authors: Ghosal Sutapa , Hemminger John C. , Bluhm Hendrik , Mun Bongjin Simon , Hebenstreit Eleonore L. D. , Ketteler Guido , Ogletree D. Frank , Requejo Felix G. , Salmeron Miquel
Published: January 2005

It has been suggested that enhanced anion concentrations at the liquid/vapor interface of airborne saline droplets are important to aerosol reactions in the atmosphere. We report ionic concentrations in the surface of such solutions. Using x-ray photoelectron spectroscopy operating at near ambient pressure, we have measured the composition of the liquid/vapor interface for deliquesced samples of potassium bromide and potassium iodide. In both cases, the surface composition of the saturated solution is enhanced in the halide anion compared with the bulk of the solution. The enhancement of anion concentration is more dramatic for the larger, more polarizable iodide anion. By varying photoelectron kinetic energies, we have obtained depth profiles of the liquid/vapor interface. Our results are in good qualitative agreement with classical molecular dynamics simulations. Quantitative comparison between the experiments and the simulations indicates that the experimental results exhibit more interface enhancement than predicted theoretically.