bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of the zebrafishnodal-related genessquintandcyclopsin patterning of mesendoderm
Authors: Dougan Scott T. , Warga Rachel M. , Kane Donald A. , Schier Alexander F. , Talbot William S.
Published: March 2003

Nodal signals, a subclass of the TGFβ superfamily of secreted factors,induce formation of mesoderm and endoderm in vertebrate embryos. We have examined the possible dorsoventral and animal-vegetal patterning roles for Nodal signals by using mutations in two zebrafish nodal-related genes, squint and cyclops, to manipulate genetically the levels and timing of Nodal activity. squint mutants lack dorsal mesendodermal gene expression at the late blastula stage, and fate mapping and gene expression studies in sqt-/-;cyc+/+ and sqt-/-;cyc+/- mutants show that some dorsal marginal cells inappropriately form hindbrain and spinal cord instead of dorsal mesendodermal derivatives. The effects on ventrolateral mesendoderm are less severe,although the endoderm is reduced and muscle precursors are located nearer to the margin than in wild type. Our results support a role for Nodal signals in patterning the mesendoderm along the animal-vegetal axis and indicate that dorsal and ventrolateral mesoderm require different levels of squintand cyclops function. Dorsal marginal cells were not transformed toward more lateral fates in either sqt-/-;cyc+/- or sqt-/-;cyc+/+ embryos, arguing against a role for the graded action of Nodal signals in dorsoventral patterning of the mesendoderm. Differential regulation of the cyclops gene in these cells contributes to the different requirements for nodal-related gene function in these cells. Dorsal expression of cyclops requires Nodal-dependent autoregulation, whereas other factors induce cyclopsexpression in ventrolateral cells. In addition, the differential timing of dorsal mesendoderm induction in squint and cyclops mutants suggests that dorsal marginal cells can respond to Nodal signals at stages ranging from the mid-blastula through the mid-gastrula.
Effects of tethering HP1 to euchromatic regions of theDrosophilagenome
Authors: Li Yuhong , Danzer John R. , Alvarez Pedro , Belmont Andrew S. , Wallrath Lori L.
Published: March 2003

Heterochromatin protein 1 (HP1) is a conserved non-histone chromosomal protein enriched in heterochromatin. On Drosophila polytene chromosomes, HP1 localizes to centric and telomeric regions, along the fourth chromosome, and to specific sites within euchromatin. HP1 associates with centric regions through an interaction with methylated lysine nine of histone H3, a modification generated by the histone methyltransferase SU(VAR)3-9. This association correlates with a closed chromatin configuration and silencing of euchromatic genes positioned near heterochromatin. To determine whether HP1 is sufficient to nucleate the formation of silent chromatin at non-centric locations, HP1 was tethered to sites within euchromatic regions ofDrosophila chromosomes. At 25 out of 26 sites tested, tethered HP1 caused silencing of a nearby reporter gene. The site that did not support silencing was upstream of an active gene, suggesting that the local chromatin environment did not support the formation of silent chromatin. Silencing correlated with the formation of ectopic fibers between the site of tethered HP1 and other chromosomal sites, some containing HP1. The ability of HP1 to bring distant chromosomal sites into proximity with each other suggests a mechanism for chromatin packaging. Silencing was not dependent on SU(VAR)3-9 dosage, suggesting a bypass of the requirement for histone methylation.
The left-right determinant Inversin is a component of node monocilia and other 9+0 cilia
Authors: Watanabe Daisuke , Saijoh Yukio , Nonaka Shigenori , Sasaki Genta , Ikawa Yayoi , Yokoyama Takahiko , Hamada Hiroshi
Published: March 2003

Inversin (Inv), a protein that contains ankyrin repeats, plays a key role in left-right determination during mammalian embryonic development, but its precise function remains unknown. Transgenic mice expressing an Inv and green fluorescent protein (GFP) fusion construct (Inv::GFP) were established to facilitate characterization of the subcellular localization of Inv. TheInv::GFP transgene rescued the laterality defects and polycystic kidney disease of Inv/Inv mice, indicating that the fusion protein is functional. In transgenic embryos, Inv::GFP protein was detected in the node monocilia. The fusion protein was also present in other 9+0 monocilia,including those of kidney epithelial cells and the pituitary gland, but it was not localized to 9+2 cilia. The N-terminal region of Inv (InvΔC)including the ankyrin repeats also localized to the node cilia and rescued the left-right defects of Inv/Inv mutants. Although no obvious abnormalities were detected in the node monocilia of Inv/Inv embryos,the laterality defects of such embryos were corrected by an artificial leftward flow of fluid in the node, suggesting that nodal flow is impaired by the Inv mutation. These results suggest that the Inv protein contributes to left-right determination as a component of monocilia in the node and is essential for the generation of normal nodal flow.
RhoA and Rac1 GTPases mediate the dynamic rearrangement of actin in peripheral glia
Authors: Sepp Katharine J. , Auld Vanessa J.
Published: March 2003

Peripheral glial cells in both vertebrates and insects are born centrally and travel large distances to ensheathe axons in the periphery. There is very little known about how this migration is carried out. In other cells, it is known that rearrangement of the Actin cytoskeleton is an integral part of cell motility, yet the distribution of Actin in peripheral glial cell migration in vivo has not been previously characterized. To gain an understanding of how glia migrate, we specifically labeled the peripheral glia of Drosophila melanogaster using an Actin-GFP marker and analyzed their development in the embryonic PNS. It was found that Actin cytoskeleton is dynamically rearranged during glial cell migration. The peripheral glia were observed to migrate as a continuous chain of cells, with the leading glial cells appearing to participate to the greatest extent in exploring the extracellular surroundings with filopodia-like Actin containing projections. We hypothesized that the small GTPases Rho, Rac and Cdc42 are involved in Actin cytoskeletal rearrangements that underlie peripheral glial migration and nerve ensheathement. To test this, transgenic forms of the GTPases were ectopically expressed specifically in the peripheral glia during their migration and wrapping phases. The effects on glial Actin-GFP distribution and the overall effects on glial cell migration and morphological development were assessed. We found that RhoA and Rac1 have distinct roles in peripheral glial cell migration and nerve ensheathement; however, Cdc42 does not have a significant role in peripheral glial development. RhoA and Rac1 gain-of-function and loss-of-function mutants had both disruption of glial cell development and secondary effects on sensory axon fasciculation. Together, Actin cytoskeletal dynamics is an integral part of peripheral glial migration and nerve ensheathement, and is mediated by RhoA and Rac1.
Zic1 repressesMath1expression via interactions with theMath1enhancer and modulation ofMath1autoregulation
Authors: Ebert Philip J. , Timmer John R. , Nakada Yuji , Helms Amy W. , Parab Preeti B. , Liu Ying , Hunsaker Thomas L. , Johnson Jane E.
Published: March 2003

Math1 is a basic helix-loop-helix transcription factor expressed in progenitor cells that give rise to dorsal commissural interneurons in the spinal cord, granule cells of the cerebellum, and sensory cells in the inner ear and skin. Transcriptional regulation of this gene is tightly controlled both temporally and spatially during nervous system development. The signals that mediate this regulation are likely integrated at the Math1enhancer, which is highly conserved among vertebrate species. We have identified the zinc-finger transcription factor Zic1 as a regulator ofMath1 expression. Zic1 binds a novel conserved site within theMath1 enhancer, and represses both the expression of endogenous Cath1(chicken homolog of Math1) and the activity of a Math1 enhancer driven lacZ reporter when expressed in chick neural tubes. Repression by Zic1 blocks the autoregulatory activity of Math1 itself. Although previous reports have shown that Zic1 and Math1 are both induced by BMP signaling,these genes appear to have opposing functions, as Math1 acts to promote neuronal differentiation in the chick neural tube and excess Zic1 appears to block differentiation. Zic1-mediated repression of Cath1transcription may modulate the temporal switch between the progenitor state and differentiating dorsal cell types during neural tube development.
A Notch-independent function of Suppressor of Hairless during the development of the bristle sensory organ precursor cell ofDrosophila
Authors: Koelzer Stefan , Klein Thomas
Published: March 2003

Su(H)/CBF1 is a key component of the evolutionary conserved Notchsignalling pathway. It is a transcription factor that acts as a repressor in the absence of the Notch signal. If Notch signalling is activated, it associates with the released intracellular domain of the Notchreceptor and acts as an activator of transcription. During the development of the mechanosensory bristles of Drosophila, a selection process called lateral inhibition assures that only a few cells are selected out of a group to become sensory organ precursors (SOP). During this process, the SOP cell is thought to suppress the same fate in its surrounding neighbours via the activation of the Notch/Su(H) pathway in these cells. We show that, although Su(H) is required to prevent the SOP fate during lateral inhibition, it is also required to promote the further development of the SOP once it is selected. Importantly, in this situation Su(H) appears to act independently of the Notch signalling pathway. We find that loss of Su(H)function leads to an arrest of SOP development because of the loss ofsens expression in the SOP. Our results suggest that Su(H) acts as a repressor that suppresses the activity of one or more negative regulator(s) ofsens expression. We show that this repressor activity is encoded by one or several genes of the E(spl)-complex. Our results further suggest that the position of the SOP in a proneural cluster is determined by very precise positional cues, which render the SOP insensitive to Dl.
Static and dynamic pressure profiles of a patellar-tendon-bearing (PTB) socket
Authors: Goh J C H , Lee P V S , Chong S Y
Published: March 2003

The purpose of this study was to evaluate the pressure distribution at the stump/socket interface in amputees wearing the patellar-tendon-bearing socket. A specially built strain gauged type pressure transducer was used for measuring this pressure distribution in four unilateral transtibial amputees. Pressure and gait parameters were measured simultaneously while they were standing and walking. Pressure profiles were compiled at 10, 25 and 50 per cent of gait cycle and compared with the pressure profiles predicted by Radcliffe in 1961. The subject's anterior-posterior pressure profiles were different from each other. However, at toe-off, each subject exhibited an increase in pressure at the patellar tendon. Their medial-lateral pressure profiles were similar: exhibiting high pressure at the medial proximal and lateral distal regions except for one subject who exhibited high pressure at the lateral proximal region instead. The subjects' pressure profiles did not resemble Radcliffe's anticipated pressure profiles. This was because ground reaction force was not the only factor affecting the resulting pressure profiles.
Executive cognitive functioning and aggression: Is it an issue of impulsivity?
Authors: Hoaken Peter N.S. , Shaughnessy Valerie K. , Pihl R.O.
Published: March 2003

A large body of research has documented a relation between the executive cognitive functions (ECFs) and interpersonal aggressive behavior. A predominant theory proposes that individuals with poor ECFs are more aggressive because they are unable to inhibit impulsive behaviors. However, evidence for this relationship is typically indirect. In this study, 46 healthy men and women completed measures of ECF, the Taylor Aggression Paradigm, and the Go/No‐Go discrimination task, a behavioral measure of impulsivity. Also, impulsiveness of participant responses during the aggression task was directly assessed by measuring latency of responses to provocation (“set‐time”). It was hypothesized that low‐quartile–scoring ECF men and women would perform more aggressively and more impulsively than high‐quartile peers. Consistent with expectations, results indicated that ECF was related to aggression and to impulsivity on the Go/No‐Go task. However, low‐ECF men and women did not have shorter set‐times; in fact, on this task, low‐ECF participants' behavioral decisions seemed slightly slower than those of high‐ECF participants. In light of these results, the authors speculate that a social information‐processing problem may mediate the ECF aggression relationship rather than altered impulsivity per se. Aggr. Behav. 29:15–30, 2003. © 2003 Wiley‐Liss, Inc.
Do beliefs about aggression predict physical aggression to partners?
Authors: Archer John , Graham‐Kevan Nicola
Published: March 2003

Three hypotheses concerning the association between instrumental (I) and expressive (E) beliefs about aggression and physical aggression were assessed among a sample comprising students (n=40), women from a domestic violence shelter (n=29), and male prisoners (n=46), all of whom had committed at least one act of physical aggression to a partner. Participants completed an adapted version of the EXPAGG [Archer and Haigh (1997a): British Journal of Social Psychology 35:1–23] to measure I and E beliefs about aggression, the Conflict Tactics Scale (CTS) [Straus (1979): Journal of Marriage and the Family 41:75–88] for themselves and their partner, and measures of fear and injuries resulting from partner violence. I beliefs predicted self‐reported physical aggression to the partner, most CTS acts of physical aggression, and injuries to the partner, with only minor and limited associations for E beliefs. Correlations for the student and prisoner samples, and for men and women, showed different strengths. The findings supported a general link between I beliefs and aggression but offered no support for the predictions that the link would be restricted to men or to men who showed a persistent pattern of violence to their partners. Aggr. Behav. 29:41–54, 2003. © 2003 Wiley‐Liss, Inc.
Variability in behavior frequencies and consistency in transactions across seasons in captive Japanese macaques (Macaca fuscata)
Authors: Abegg C. , Petit O. , Thierry B.
Published: March 2003

Consistent interspecific differences are found in macaque species, ranging from highly hierarchical and nepotistic societies to more tolerant and open social organizations. It still remains to be demonstrated whether intraspecific variation is narrower than interspecific variation. Herein, we quantified social behavior in a captive group of Japanese macaques (Macaca fuscata) to estimate the range of intraspecific variation for a full array of measurements in three different seasons. Despite an increased frequency of aggression found on the part of males during the mating season, the form of the behaviors performed remained relatively unchanged. Transactions during conflicts, approaches, or grooming did not undergo significant variations in relation to season. Frequencies and durations seemed more sensitive to demographic and environmental variations. The values measured in the study group are representative of the Japanese macaque. The results validate the use of transaction measurements in interspecific comparisons, providing that additional factors such as age and sex are taken into account. Aggr. Behav. 29:81–93, 2003. © 2003 Wiley‐Liss, Inc.
Attributes of high‐quality intensive courses
Authors: Scott Patricia A.
Published: March 2003

This chapter outlines the best teaching strategies to use in intensive courses to achieve the best possible learning outcomes.
Developing and maintaining accelerated degree programs within traditional institutions
Authors: Husson William J. , Kennedy Tom
Published: March 2003

This chapter describes some of the essential criteria and elements for initiating and sustaining a successful accelerated degree program.
Distance learning and service‐learning in the accelerated format
Authors: Burton Elise M.
Published: March 2003

The Service Oriented Field Experience presents adult distance learners with the experiential and reflective components of service‐learning in an accelerated course. The result is often a transformative academic experience.
Intuitions and introspections about imagery: the role of imagery experience in shaping an investigator's theoretical views
Authors: Reisberg Daniel , Pearson David G. , Kosslyn Stephen M.
Published: March 2003

Early in a scientific debate, before much evidence has accumulated, why are some scientists inclined toward one position and other scientists toward the opposite position? We explore this issue with a focus on scientists' views of the ‘imagery debate’ that unfolded in Cognitive Science during the late 1970s and early 1980s. We examine the possibility that, during the early years of this debate, researchers' views were shaped by their own conscious experiences with imagery. Consistent with this suggestion, a survey of 150 psychologists, philosophers, and neuroscientists showed that those who experienced their own visual imagery as vivid and picture‐like recall being more sympathetic in 1980 to the view that, in general, images are picture‐like. Similarly, those who have vivid images and who regularly use their images in cognition were more inclined to believe that issues of image vividness deserve more research. Copyright © 2002 John Wiley & Sons, Ltd.
Children's recall and the cognitive interview: do the positive effects hold over time?
Authors: Larsson Anneli S. , Anders Granhag Pär , Spjut Emma
Published: March 2003

Most studies investigating how the Cognitive Interview affects children's recall have employed short retention intervals (a week or less). In our study children (10–11 years old) saw a film picturing an extraordinary performance by a professional fakir. Half of the children were interviewed after seven days (n = 24) and the other half after six months (n = 25). At each test session, half were interviewed according to the Cognitive Interview (CI), and half according to the Structured Interview (SI). We found that: (a) the children in the CI condition recalled significantly more correct information than the children in the SI condition (both after seven days and after six months), and (b) the children interviewed after seven days recalled significantly more correct information, and less confabulations, compared to the children interviewed after six months. The results suggest that the CI can be used as an investigative tool both after short and long retention intervals. Copyright © 2002 John Wiley & Sons, Ltd.
Electron Energetics at Surfaces and Interfaces: Concepts and Experiments
Authors: Cahen D. , Kahn A.
Published: March 2003

We present a concise, although admittedly non‐exhaustive, but hopefully didactic review and discussion of some of the central and basic concepts related to the energetics of surfaces and interfaces of solids. This is of particular importance for surfaces and interfaces that involve organic molecules and molecular films. It attempts to pull together different views and terminologies used in the solid state, electrochemistry, and electronic device communities, regarding key concepts of local and absolute vacuum level, surface dipole, work function, electron affinity, and ionization energy. Finally, it describes how standard techniques like photoemission spectroscopy can be used to measure such quantities.
Patterning of Polypeptide Thin Films by the Combination of Surface‐Initiated Vapor‐Deposition Polymerization and Photolithography
Authors: Wang Y. , Chang Y.C.
Published: March 2003

A solvent‐free strategy offering a fast, economical, and clean approach to integrate polypeptide materials into micrometer‐scale devices is presented. The dimensions and compositions can be controlled in both the lateral and vertical directions. The Figure shows a surface‐grafted pattern composed of PMLG (poly(γ‐methyl‐L‐glutamate)) and PMLG‐b‐PBLG, (B indicates benzyl instead of methyl).
A Conducting Polymer Artificial Muscle with 12 % Linear Strain
Authors: Bay L. , West K. , Sommer‐Larsen P. , Skaarup S. , Benslimane M.
Published: March 2003

A soft polymer actuatorhas been constructed based on the volume change of a conducting polymer. The linear expansion (12 % at a load of 0.5 MPa) is the highest yet reported for a centimeter‐scale conducting polymer actuator. This is achieved by controlling the structure on several length scales: Choice of molecular structure, synthesis from a structured medium, and forming the polymer actuator on a compliant, microstructured gold electrode.
High‐Energy Photonic Bandgap in Sb2S3 Inverse Opals by Sulfidation Processing
Authors: Juárez B.H. , Ibisate M. , Palacios J.M. , López C.
Published: March 2003

Large Sb2S3 inverse opals have been prepared that show extraordinary photonic behavior. A wide and well‐defined peak in the reflectance spectrum in the range 700–800 nm defines the most energetic full photonic bandgap in the literature. The homogeneity (see Figure) and degree of infiltration of the samples improve on those prepared by CBD methods.
Divanadium Pentoxide Nanorods
Authors: Pinna N. , Wild U. , Urban J. , Schlögl R.
Published: March 2003

The reverse micelle technique, here used to synthesize divanadium pentoxide nanorods, enables the nanorod length to be tuned easily by simply keeping them in the micellar solution after the synthesis. The nanorods are characterized by transmission electron microscopy, X‐ray photoemission spectroscopy, and X‐ray diffraction. These techniques show that the nanorods are made of divanadium pentoxide with the structure of γ‐V2O5.
Medium Effect on the Electron Cooling Dynamics in Gold Nanorods and Truncated Tetrahedra
Authors: Link S. , Hathcock D.J. , Nikoobakht B. , El‐Sayed M.A.
Published: March 2003

A study on the electron relaxation dynamics and thermal cooling of colloidal gold nanoparticles (see Figure) in air and water finds that the local energy exchange with the surrounding medium occurs on the picosecond time scale, comparable with the electron–phonon relaxation, while a slow heat dissipation by water ensures that the particles remain heated for hundreds of picoseconds.
Frequent and prolonged hospitalizations: A risk factor for early mortality in sickle cell disease patients
Authors: Houston‐Yu Patricia , Rana Sohail R. , Beyer Betsy , Castro Oswaldo
Published: March 2003

A subset of patients with sickle cell disease (SCD) has frequent and prolonged hospitalizations. Clinical outcomes for this subset of patients are not known. We analyzed mortality data in 71 such patients enrolled in a case management study. Adult patients (mean age 32 years) with SCD and ≥50 hospitalization days/year or ≥6 admissions/year were enrolled. Clinical and psychosocial data were obtained. During a mean 24‐month follow up, 11 of 71 patients died (15.5%). Patients who died had a higher mean number of hospitalization days in the year before study entry (116 vs. 40, P < 0.000008) and were also more depressed than those who survived (mean score 17.8 vs. 11.9, P = 0.031). Frequent and prolonged hospitalizations are a risk factor for early mortality in patients with SCD. Am. J. Hematol. 72:201–203, 2003. © 2003 Wiley‐Liss, Inc.
BMI in the Trois‐Rivières study: Child–adult and child–parent relationships
Authors: Trudeau François , Shephard Roy J. , Bouchard Stephane , Laurencelle Louis
Published: March 2003

This study evaluated intraindividual child–adult and interindividual child–parent relationships of body mass index (BMI) using data from the Trois‐Rivières semilongitudinal study of growth and development. Intraindividual correlations between age 12 and 35 years were substantial (r2 = 36% of variance in women, 30% of variance in men). Interindividual child–parent correlations for mothers and fathers age 36.6 ± 0.4 and 39.5 ± 0.4 years, respectively, were very low to low for daughters age 12 years (r = 0.09, NS and 0.34, P < 0.001 vs. father and mother, respectively) but all very low for sons age 12 years (r = 0.07, NS and 0.16, NS vs. father and mother, respectively). A multiple regression analysis predicted adult BMI from the individual's BMI at 10, 11, 12 years plus the maternal and paternal BMIs as calculated from self‐reported heights and weights. The BMI at age 12 years was a better predictor of adult BMI than the parental BMI in both men and women (P < 0.001) and multivariate analysis revealed that this index at age 12 years was the sole significant predictor of adult BMI for both men and women. The results from our study do not support the hypothesis that parental BMI is a stronger predictor of adult BMI than childhood BMI. However, useful information for the prediction and prevention of adult overweight can be obtained from the BMI at age 12 years. Our results suggest that environmental influences may be the major factor in the present obesity epidemic. Am. J. Hum. Biol. 15:187–191, 2003. © 2003 Wiley‐Liss, Inc.
Genetic structure and affinities of the corsican population (France): Classical genetic markers analysis
Authors: Vona G. , Moral P. , Memmì M. , Ghiani M.E. , Varesi L.
Published: March 2003

The frequencies of 19 classical genetic markers for a total of 54 alleles were studied in a sample of 1,164 individuals born and residing in five different regions of Corsica. The results, which are also discussed in the context of the Mediterranean populations, show the existence within Corsica of a certain genetic differentiation between north and south which follows the linguistic subdivision differentiation. Compared to the other Mediterranean populations, Corsica also appears to be greatly differentiated from the populations of regions such as France and Tuscany, regions which have had great political and cultural influence. The Mediterranean population most comparable to Corsica is Sardinia. Despite their common origin, however, they do not prove to be absolutely identical. The genetic characteristics of Corsica and their relationship with the Mediterranean populations are interpreted in terms of demographic and matrimonial structure, isolation, and genetic drift. Am. J. Hum. Biol. 15:151–163, 2003. © 2003 Wiley‐Liss, Inc.
Mixed‐longitudinal analysis of growth data from malian adolescent girls: Evidence for compensatory gain?
Authors: Pawloski Lisa R.
Published: March 2003

Cross‐sectional data have previously indicated poor growth and development among adolescent girls in Mali. These data have shown that Malian girls are shorter and lighter than their United States female counterparts. Many studies suggest that this evidence of poor growth and development is due to a combination of poor nutrient intake, high‐energy expenditure, and poor access to health care. At adolescence, individuals rarely follow a standard pattern of growth due to different biological timetables and expressions of pubertal growth. By examining velocity of growth, researchers can recognize developmental patterns such as compensatory gain. This study examines the growth rates of Malian girls over a 6‐month period. Anthropometric data were collected from a total of 1,045 adolescent girls ages 10–17 years. Height and weights were collected twice from the Segou Coura community in the town of Segou and from the Dioro Arrondissement in 1997. From these data, mixed longitudinal analyses were conducted. Both the height and weight velocity data showed patterns of delayed growth rates when compared with American girls. Although Malian girls are similar to American girls in that they tend to reach their peak height velocity at age 12, the Malian girls demonstrate a longer growth spurt than the American girls. This evidence of greater height velocity may be an indication of compensatory growth, or compensatory gain, and is partially supported from cross‐sectional data. While these Malian data do not show much evidence that certain stressors are relieved during adolescence, only more extensive longitudinal data can more fairly examine the issue. Am. J. Hum. Biol. 15:178–186, 2003.©2003 Wiley‐Liss, Inc.
Personality profiles of children and adolescents with neurofibromatosis type 1
Authors: Prinzie P. , Descheemaeker M.J. , Vogels A. , Cleymans T. , Haselager G.J.T. , Curfs L.M.G. , Hellinckx W. , Onghena P. , Legius E. , van Lieshout C.F.M. , Fryns J.‐P.
Published: March 2003

The personality profile of 44 youngsters (24 males, 20 females; mean age 11 years, 3 months) with neurofibromatosis type 1 (NF1) was compared with a group of 220 non‐NF1 control youngsters (matched on age and gender). Personality characteristics of each youngster were rated by both parents, using the California Child Q‐set (CCQ); [Block and Block, 1980]. The scores on eight personality dimensions were compared, i.e., Extraversion, Agreeableness, Conscientiousness, Emotional Stability, Openness, Motor Activity, Irritability, and Dependency. Moreover, personality of NF1 youngsters was related to IQ level, severity of medical problems, the presence or absence of visible cosmetic disfigurements, and de novo versus familial origin of NF1. The personality profile of NF1 youngsters was markedly different from the non‐NF1 youngsters. Compared to the 220 control children, they were equally agreeable, but less conscientious, less emotionally stable, less open for new experience, with less motor activity, and more extravert, more dependent, and more irritable. Personality characteristics were similar for children with maternally or paternally inherited NF1, or for children with a new mutation. There was no association with gender, the severity of medical and cosmetic problems, and IQ. © 2003 Wiley‐Liss, Inc.
Child with De Novo t(1;6)(p22.1;p22.1) translocation and features of ectodermal dysplasia with hypodontia and developmental delay
Authors: Asamoah Alexander , Decker Amy B. , Wiktor Anne , Van Dyke Daniel L.
Published: March 2003

We report on a 6.5‐year‐old girl with a balanced translocation between the short arms of chromosomes 1 and 6. She was referred for genetics evaluation because of developmental speech delay and congenital absence of several deciduous and permanent teeth. She was very sensitive to noise (hyperacusis), had poor hair and nail growth, decreased sweating, and turned very red with high fever. She had microcephaly (head circumference at the second centile; weight and height were at 25th centile), short palpebral fissures, epicanthal folds, sparse eyelashes, large ears, partial anodontia, short finger and toenails, and dry skin. She had mild developmental delay. Family history was significant for learning problems in two paternal uncles, one paternal aunt, and several paternal cousins. Thyroid studies, calcium, phosphorus, and alkaline phosphatase levels were normal. Her karyotype was 46,XX,t(1;6)(p22.1;p22.2), and parental karyotypes were normal. This apparently balanced translocation may have resulted in either a submicroscopic loss or disruption of a gene or genes involved in ectodermal dysplasia. There are no reported cases of ectodermal dysplasia associated with this chromosome rearrangement. © 2003 Wiley‐Liss, Inc.
Cytogenetic analysis of obsessive‐compulsive disorder (OCD): Identification of a FRAXE fragile site
Authors: Wang Qing , Gu Yanghong , Ferguson James M. , Chen Qiuyun , Boatwright Scott , Gardiner James , Below Cheryl , Espinosa Janna , Nelson David L. , Shaffer Lisa G.
Published: March 2003

Obsessive‐compulsive disorder (OCD) is a chronic psychiatric disease characterized by recurrent obsessions, compulsions, or both. The prevalence rate of OCD is 2.1% in the general population. Here we report cytogenetic analysis of 26 patients affected with OCD. In one male patient (OCD‐K33), we identified a fragile X chromosome by cytogenetic analysis with 21% of cells demonstrating a fragile site at Xq27‐q28. Polymerase chain reaction (PCR) and Southern blot analysis demonstrated that the molecular basis of the OCD‐K33 fragile X chromosome was expansion of the CCG repeat at FRAXE. The number of the expanded repeats was estimated to be more than 300 copies, qualifying it as a full FRAXE mutation. Further analysis of the family members of OCD‐K33 revealed another member with a full FRAXE mutation (630–1,200 copies of the CCG repeat), who had the clinical phenotype of speech impairment, and two other members with normal phenotypes and no FRAXE expansion. The two FRAXE expansions lead to complete methylation at the CCG repeat. The co‐segregation of the full FRAXE mutation with apparent neurologic disorders in the same family provides further support to the notion that FRAXE is a genetic neurologic condition. Our findings expand the spectrum of clinical phenotypes associated with FRAXE mutations. © 2003 Wiley‐Liss, Inc.
Continuing the search for dyslexia genes on 6p
Authors: Grigorenko Elena L. , Wood Frank B. , Golovyan Lina , Meyer Marianne , Romano Christina , Pauls David
Published: March 2003

This study is a continuation and extension of the work with Orton Developmental Dyslexia (DD) pedigrees [Grigorenko et al., 1997; 2000, Grigorenko et al., 2001]. This study utilized an extended sample (N = 176) and a well‐saturated map of chromosome 6p (30 markers). Six phenotypes were constructed to span a range of dyslexia‐related cognitive processes. These phenotypes were: (1) Phonemic Awareness (of spoken words); (2) Phonological Decoding (of printed nonwords); (3) Rapid Automatized Naming (of colored squares or object drawings); (4) Single Word Reading (orally, of printed real words); (5) Phonemic Awareness/Decoding/Single‐Word Reading pathway; and (6) Phonemic Awareness/Rapid Naming/Single‐Word Reading pathway. The study resulted in two major findings. First, considering the distributions of the genetic linkage indicators across all phenotypes examined, there appear to be three regions of interest (around markers D6S109, D6S1261, and in the D6S105–D6S265 region). Any of these regions could serve as a starting point in the search for specific gene candidates contributing to the manifestation of DD, yet they all might be echo peaks of a single peak, the boundary of which is difficult to establish due to the limited power of this sample. Second, the DD‐related linkage in 6p21.3 appears to be most closely related to the manifestations of DD through phonemic awareness and single‐word reading deficits. © 2003 Wiley‐Liss, Inc.
Transcriptional activities of cholecystokinin promoter haplotypes and their relevance to panic disorder susceptibility
Authors: Ebihara Mitsuru , Ohba Hisako , Hattori Eiji , Yamada Kazuo , Yoshikawa Takeo
Published: March 2003

We previously identified a polymorphic compound short tandem repeat (STR) in the 5′‐regulatory region of the cholecystokinin (CCK) gene, and showed that when the STRs were classified into three groups based on length and linkage disequilibrium behavior with neighboring variants, the medium class allele was significantly associated with panic disorder. The present study examined the transcriptional activity of the CCK promoter construct containing the STR and downstream −188A/G variation. The STRs acted as transcriptional repressors with a similar potency among the three classes, but the long (L) class STR exhibited a synergistic effect on decreasing promoter activity when combined with −188G. The haplotype composed of the L class of STR and −188G was significantly less frequent in panic disorder (P = 0.0032; odds ratio, 95% confidence interval = 0.06, 0.01–0.69). These results suggest that the L‐(−188G) haplotype may act as a protective factor against panic by reducing the expression of anxiogenic CCK. © 2003 Wiley‐Liss, Inc.
Demography, female life history, and reproductive profiles among the chimpanzees of Mahale
Authors: Nishida Toshisada , Corp Nadia , Hamai Miya , Hasegawa Toshikazu , Hiraiwa‐Hasegawa Mariko , Hosaka Kazuhiko , Hunt Kevin D. , Itoh Noriko , Kawanaka Kenji , Matsumoto‐Oda Akiko , Mitani John C. , Nakamura Michio , Norikoshi Koshi , Sakamaki Tetsuya , Turner Linda , Uehara Shigeo , Zamma Koichiro
Published: March 2003

Demography provides critical data to increase our understanding of the evolution, ecology, and conservation of primate populations. The chimpanzees of the Mahale Mountains National Park, Tanzania, have been studied for more than 34 yr on the basis of individual identification and standardized attendance records. From this long‐term study, we derived the following demographic data: The major cause of death was disease (48%), followed by senescence (24%) and within‐species aggression (16%). Fifty percent of Mahale chimpanzees died before weaning. The median ages of female life history variables were: first maximal swelling, 10.0 yr (n=5); emigration, 11.0 yr (n=11); and first birth, 13.1 yr (n=5). The median period of adolescent infertility was 2.8 yr (n=4) when calculated from the age at immigration to that at first birth. Female fecundity was highest between 20 and 35 yr of age, with an annual birth rate of 0.2. Twenty‐six females that were observed from a young age (10–13 yr) to death at various ages (15–40 yr) gave birth to an average of 3.9 and weaned an average of 1.4 offspring. Twenty‐five females that were observed from middle age (18–33 yr) to death in older age (31–48) gave birth to an average of 2.7 and weaned an average of 2.0 offspring. The post‐reproductive lifespan for female chimpanzees was defined as the number of years that passed from the year when the last offspring was born to the year when the female died, minus 5. Twenty‐five percent of old females had a post‐reproductive lifespan. The interbirth interval after the birth of a son (x̄ = 72 mo) tended to be longer than that after the birth of a daughter (x̄ = 66 mo). The extent of female transfer, which is a rule in chimpanzees, is influenced by the size and composition of the unit group and size of the overall local community. Am. J. Primatol. 59:99–121, 2003. © 2003 Wiley‐Liss, Inc.
Growth‐related shape changes in the fetal craniofacial complex of humans (Homo sapiens) and pigtailed macaques (Macaca nemestrina): A 3D‐CT comparative analysis
Authors: Zumpano Michael P. , Richtsmeier Joan T.
Published: March 2003

This study investigates whether macaques and humans possess a common pattern of relative growth during the fetal period. The fetal samples consist of 16 male pigtailed macaques (mean age, 20.5 gestational weeks) and 17 humans (9 males and 8 females; mean age, 29.5 gestational weeks). For each individual, three‐dimensional coordinates of 18 landmarks on the skull were collected from three‐dimensional computed tomographic (CT) reconstructed images and two‐dimensional CT axial slices. Early and late groups were created from the human (early mean age, 24 weeks, N = 8; late mean age, 34 weeks, N = 9) and macaque samples (early mean age, 17.7 weeks, N = 7; late mean age, 23 weeks, N = 9). Inter‐ and intraspecific comparisons were made between the early and late groups. To determine if macaques and humans share a common fetal pattern of relative growth, human change in shape estimated from a comparison of early and late groups was compared to the pattern estimated between early and late macaque groups. Euclidean distance matrix analysis was used in all comparisons. Intraspecific comparisons indicate that the growing fetal skull displays the greatest amount of change along mediolateral dimensions. Changes during human growth are primarily localized to the basicranium and palate, while macaques experience localized change in the midface. Interspecific comparisons indicate that the two primate species do not share a common pattern of relative growth, and the macaque pattern is characterized by increased midfacial growth relative to humans. Our results suggest that morphological differences in the craniofacial skeleton of these species are in part established by differences in fetal growth patterns. Am J Phys Anthropol 120:339–351, 2003. © 2003 Wiley‐Liss, Inc.
Differential phenotypic variability among the Apalachee mission populations of La Florida: A diachronic perspective
Authors: Stojanowski Christopher M.
Published: March 2003

Phenotypic variability is evaluated in a series of skeletal samples from the Apalachee region of Florida. Based on ethnohistoric evidence, several predictive models for changes in variability are generated. If variability decreases through time, this likely represents the effect of genetic drift in populations experiencing epidemic disease and population loss. If variability increases through time, this suggests that population aggregation or genetic admixture were primary factors shaping the Apalachee population during the mission period. Dental dimensions were collected from a series of precontact (pre‐1500), early mission (AD 1633–1650) (San Pedro y San Pablo de Patale), and late mission (post‐1657) (San Luis) samples from the Apalachee region and were subjected to univariate and multivariate variability analyses. The results indicate that the late mission San Luis sample was significantly more variable than the Patale or precontact samples; however, the Patale sample exhibited no significant variability change in comparison to the precontact population. This suggests that the missions initially effected limited change in genetic variability in the mission populations. However, San Luis was affected by either admixture or population aggregation to such a degree that the observed variation had increased beyond earlier levels. Given the limited historic evidence for population aggregation at this mission, and the comparatively large resident Spanish population, the increased variability may be indicative of admixture at this mission, and potentially at this mission only. Based on a limited data set, however, it appears that the mission period cannot be typified by a single evolutionary or historic process. Am J Phys Anthropol 120:352–363, 2003. © 2003 Wiley‐Liss, Inc.
Mitochondrial DNA affinities at the Atlantic fringe of Europe
Authors: González Ana M. , Brehm Antonio , Pérez José A. , Maca‐Meyer Nicole , Flores Carlos , Cabrera Vicente M.
Published: March 2003

Mitochondrial DNA analysis of Atlantic European samples has detected significant latitudinal clines for several clusters with Paleolithic (H) and Neolithic (J, U4, U5a1, and U5a1a) coalescence ages in Europe. These gradients may be explained as the result of Neolithic influence on a rather homogeneous Paleolithic background. There is also evidence that some Neolithic clusters reached this border by a continental route (J, J1, J1a, U5a1, and U5a1a), whereas others (J2) did so through the Mediterranean coast. An important gene flow from Africa was detected in the Atlantic Iberia. Specific sub‐Saharan lineages appeared mainly restricted to southern Portugal, and could be attributed to historic Black slave trade in the area and to a probable Saharan Neolithic influence. In fact, U6 haplotypes of specific North African origin have only been detected in the Iberian peninsula northwards from central Portugal. Based on this peculiar distribution and the high diversity π value (0.014 ± 0.001) in this area compared to North Africa (0.006 ± 0.001), we reject the proposal that only historic events such as the Moslem occupation are the main cause of this gene flow, and instead propose a pre‐Neolithic origin for it. Am J Phys Anthropol 120:391–404, 2003. © 2003 Wiley‐Liss, Inc.
Human life histories and the demographic transition: A case study from Finland, 1870–1949
Authors: Korpelainen Helena
Published: March 2003

The life histories of humans who were engaged in reproduction during the demographic transition were investigated. It was discovered that these life histories were subject to great changes during the period involving the birth cohorts from the years 1870–1949. Although the number of all and surviving children decreased during this period, the individual fitness values (λ) of females remained quite even. The λ values are sensitive not only to reproductive quantity but also to the timing of reproduction. Therefore, the effective change in female fitness during the demographic transition may not be as dramatic as previously thought. When studying the level of selection (or rather the opportunity for selection), it was found that mortality selection steadily decreased to a very low level. However, fertility selection and total selection, which were relatively low for the cohorts 1870–1889, increased before the steep decrease that was detected for the cohorts 1930–1949. The situation reflects the presence of considerable variance in fertility for the cohorts 1890–1929, when the mean fertility was decreasing. A previously found trade‐off between female longevity and reproductive success appeared less significant, apparently due to the presence of more plentiful resources and voluntary limitation of reproduction. The deviation from the potential fitness maximization and the presence of subfertility have become prevalent in human populations. Am J Phys Anthropol 120:384–390, 2003. © 2003 Wiley‐Liss, Inc.
Mechanical and thermal properties of starch‐filled poly(D,L‐lactic acid)/poly(hydroxy ester ether) biodegradable blends
Authors: Garlotta Donald , Doane William , Shogren Randal , Lawton John , Willett J. L.
Published: March 2003

The mechanical, structural, and thermal properties of injection‐molded composites of granular cornstarch, poly(D,L‐lactic acid) (PDLLA), and poly(hydroxy ester ether) (PHEE) were investigated. These composites had high tensile strengths, ranging from 17 to 66 MPa, at starch loadings of 0–70 wt %. Scanning electron microscopy micrographs of fracture specimens revealed good adhesion between the starch granule and the polymer matrix, as evidenced by broken starch granules. The adhesion of the starch granules to the polymer matrix was the greatest when the matrix PDLLA/PHEE ratios ranged from zero to unity. At a PDLLA/PHEE ratio of less than unity, as the starch content increased in the composites, there was an increase in the tensile strength and modulus, with a concurrent decrease in elongation. The effects of starch on the mechanical properties of starch/PDLLA composites showed that as the starch content of the composite increased, the tensile strength and elongation to break decreased, whereas Young's modulus increased. In contrast, the tensile strength of starch/PHEE composites increased with increasing starch content. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1775–1786, 2003
Fracture behavior of carbon fiber reinforced plastics determined by the time–frequency analysis method
Authors: Nam Ki‐Woo , Ahn Seok‐Hwan , Moon Chang‐Kwon
Published: March 2003

Fourier transform has been used to study the frequency characteristics of a signal. However, based on the Fourier transform and power spectrum alone, it is hard to tell whether or not the frequency content of a signal evolves over time, even though the phase of the Fourier transform relates to time shifting. On the other hand, except for a few special cases, the frequency content of the majority of signals encountered in the real world change with time. Recently, to overcome the problem that Fourier transform is unable to represent a nonstationary signal, time–frequency analysis methods that can simultaneously represent information about the time and frequency of a signal have been developed. In this study, the damage process of cross‐ply carbon fiber reinforced plastics (CFRP) during a monotonic tensile test was characterized by acoustic emission (AE). Different laminated types of CFRP were used to determine the characteristics of the AE signal and frequency. The time–frequency analysis method was found to be useful for the determination of the fracture mechanism in CFRP (such as, matrix cracking, debonding–delamination, and fiber fracture). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1659–1664, 2003