bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunohistochemical Expression of HIF‐1α in Response to Early Myocardial Ischemia
Authors: Pampín José Blanco , García Rivero Sonia Aranzazu , Otero Cepeda Xosé Luis , Boquete Angel Vázquez , Vila Jerónimo Forteza , Fonseca Rafael Hinojal
Published: March 2006

ABSTRACT: This study aims to evaluate the effects of ischemia on the myocardial fibers and the expression of the transcriptional factor for angiogenesis hypoxia‐inducible factor‐1 alpha (HIF‐1α) in human heart specimens. We have prospectively analyzed the HIF‐1α expression in human ischemic hearts with the ABC‐inmunohistochemistry technique and amplification by biotinylated tyramide. The relationship between the expression of HIF‐1α and the temporal evolution of ischemia has also been evaluated. As pathomorphological diagnosis of early myocardial ischemia has many problems in human autopsy material with less than 4 to 6 h after clinical onset, we suggest that HIF‐1α is helpful in the early acute myocardial infarction diagnosis, so it stains necrotic areas within the first 2 h. The amplification procedure provides a higher intensity of the final staining without losing specificity. It is concluded that in normal cardiac fibers, basal expression of HIF‐1α is not appreciable, but it steadily increases after ischemia. With regard to the practical applicability in forensic field, our observations suggest that positive immunohistochemical expression of HIF‐1α on heart samples may be used as a reliable indicator of myocardial damage in cases without cardiac lesion evidence, using conventional microscopy. This method is especially useful and may provide definitive proof of myocardial ischemia in unexpected deaths without previous symptoms, or in forensic cases with a short period of clinical manifestations. In addition, it may have been involved in possible future cardiovascular therapies.
Genetic Polymorphisms of 15 STR Loci in a Japanese Population
Authors: Tie Jian , Wang Xiuling , Oxida Shigemi
Published: March 2006

POPULATION: A total of 650 unrelated Japanese individuals living in Tokyo area.
Allele Frequency Distributions at Three Pentanucleotide Repeat STRs in a Japanese Population
Authors: Ohtaki Hiroyuki , Yamamoto Toshimichi , Yoshikawa Shogo , Yoshimoto Takashi , Uchihi Rieko , Katsumata Yoshinao
Published: March 2006

POPULATION: Japanese.
Analysis of Y‐STR Loci in a Population Sample from Northeast China
Authors: Wang Xiuling , Sawaguchi Toshiko
Published: March 2006

POPULATION: A total of 141 unrelated Chinese Han male individuals living in Liaoning in northeast China.
Osteoblast‐like cells are sensitive to submicron‐scale surface structure
Authors: Zhao Ge , Zinger Olivier , Schwartz Zvi , Wieland Marco , Landolt Dieter , Boyan Barbara D.
Published: March 2006

Objectives: Studies showing that osteoblasts exhibit a more differentiated phenotype on rough titanium (Ti) surfaces and osteoclast‐resorbed bone surfaces used materials characterized by average peak to valley distance (Ra). Other surface features impacting the cells include distance between peaks, curvature of the valleys, and relative distribution of flat and smooth regions. We used novel Ti surfaces prepared by electrochemical micromachining as models to examine specific contributions of individual design features to osteoblast response. Results show that micron‐scale topography modulates cell number, cell morphology and prostaglandin E2 (PGE2). In the presence of the appropriate microtopography, submicron‐scale rugosity modulates differentiation and transforming growth factor‐β1 (TGF‐β1) levels. In this study, we examined the role of different types of submicron‐scale structures.

Material and methods: Thirty micrometer diameter craters on Ti disks were produced by photolithography resulting in an electropolished smooth surface, and arranged so that inside crater area vs. outside flat area was 6 (30/6). Submicron‐scale structures were superposed by acid etching and porous anodization. Ra's were 700, 400, 60 nm on acid‐etched, porous anodized and smooth 30/6 surfaces, respectively.

Results: MG63 osteoblast‐like cells were sensitive to submicron‐scale architecture. Cell morphology on anodized surfaces was similar to morphology on smooth surfaces, whereas on etched surfaces, cells had a more elongated differentiated shape. Cell number was greatest on smooth surfaces>anodized>etched. Osteocalcin and PGE2 were affected in a reverse manner. Active TGF‐β1 was greatest on etched 30/6 surfaces>anodized>smooth; latent TGF‐β1 was elevated on all rough surfaces.

Conclusions: These results support our previous observations that submicron‐scale structures modulate osteoblastic phenotype and show that the physical properties of the submicron‐scale structures are important variables in determining osteoblast response to substrate topography.
Significance of primary stability for osseointegration of dental implants
Authors: Lioubavina‐Hack Natalia , Lang Niklaus P. , Karring Thorkild
Published: March 2006

Aim: To investigate the significance of the initial stability of dental implants for the establishment of osseointegration in an experimental capsule model for bone augmentation.

Material and methods: Sixteen male rats were used in the study. In each rat, muscle‐periosteal flaps were elevated on the lateral aspect of the mandibular ramus on both sides, resulting in exposure of the bone surface. Small perforations were then produced in the ramus. A rigid, hemispherical Teflon® capsule with a diameter of 6 mm and a height of 4 mm and with a hole in its middle portion, prepared to fit the circumference of an ITI® HC titanium implant of 2.8 mm in diameter, was fixed to the ramus using 4 mini‐screws. On one side of the jaw, the implant was placed through the hole in such a way that its apex did not make contact with the mandibular ramus (test). This placement of the implant did not ensure primary stability. On the other side of the jaw, a similar implant was placed through the hole of the capsule in such a way that contact was made between the implant and the surface of the ramus (control). This provided primary stability of the implant. After placement of the implants, the soft tissues were repositioned over the capsules and sutured. After 1, 3, 6 and 9 months, four animals were sacrificed and subjected to histometric analysis.

Results: The mean height of direct bone‐to‐implant contact of implants with primary stability was 38.8%, 52.9%, 64.6% and 81.3% of the implant length at 1, 3, 6 and 9 months, respectively. Of the bone adjacent to the implant surface, 28.1%, 28.9%, 52.6% and 69.6%, respectively, consisted of mineralized bone. At the test implants, no bone‐to‐implant contact was observed at any observation time or in any of these non‐stabilized specimens.

Conclusion: The findings of the present study indicate that primary implant stability is a prerequisite for successful osseointegration, and that implant instability results in fibrous encapsulation, thus confirming previously made clinical observations.
Systemic arteriopathy in SIV‐infected rhesus macaques (Macaca mulatta)
Authors: Yanai Tokuma , Lackner Andrew A. , Sakai Hiroki , Masegi Toshiaki , Simon Meredith A.
Published: March 2006

Background  Severe disseminated vasculopathy was observed in two simian immunodeficiency virus (SIV)‐infected rhesus macaques (Macaca mulatta). These animals developed clinical signs of AIDS, including lymphadenopathy, weight loss, diarrhea and collapse.

Results and discussion  Grossly, both animals showed emaciation, lymphadenopathy, vegetations on the mitral valve, renal infarcts and a dilated intestine; one animal had multifocal hemorrhages in multiple organs. Histologically, both cases had disseminated arteriopathy characterized by intimal thickening and fibrosis with varying degrees of vasculitis. The lesion was prominent in the kidney, intestine, pancreas, liver, heart, lymph nodes, spleen and testis. Occasional venules had intimal thickening. Both cases had cytomegalovirus (CMV) infection with intranuclear inclusions, CMV antigen and nucleic acid; some inclusions were observed in endothelial cells within some of the vascular lesions in one of the two. These data suggest that CMV caused the unusual lesions.
MORPHOMETRIC ASSESSMENT OF THE PROXIMAL PORTION OF THE TIBIA IN DOGS WITH AND WITHOUT CRANIAL CRUCIATE LIGAMENT RUPTURE
Authors: OSMOND CHRISTIAN S. , MARCELLIN‐LITTLE DENIS J. , HARRYSSON OLA L. A. , KIDD LINDA B.
Published: March 2006

Based on the clinical observation that dogs with a steep tibial plateau slope had variable tibial morphology, we hypothesized that these dogs could be further characterized using measurements developed by examining computer generated models of specific proximal tibial malformations. A 3D tibial model was created from a normal canine tibia. The model was manipulated to reproduce two specific proximal tibial anomalies representing deformities originating from the tibial plateau or the proximal tibial shaft. Data from these models were used to create specific measurements that would characterize the shape of these anomalies. These measurements included the diaphyseal tibial axis (DTA)/proximal tibial axis (PTA) angle, which defined the orientation of the proximal portion of the shaft in relation to the tibial mid‐shaft. These measurements were then made on radiographs of dogs with and without cranial cruciate ligament (CCL) rupture. Models with tibial plateau and proximal shaft deformities had a steep tibial plateau slope (TPS). Models with proximal shaft deformity had a markedly increased DTA/PTA angle. The model with a 10° proximal shaft deformity had a DTA/PTA angle of 11.23°. Six dogs (9.0%) had a DTA/PTA angle larger than 11.23° (range, 11.4–13.9°). Dogs in this group had ruptured CCL and a steep TPS. Dogs with CCL rupture had higher TPS (mean, 31.8±4.1°) and DTA/PTA angle (mean, 6.0±3.3°) than dogs without CCL rupture (means, 23.6±3.4° and 4.1±2.2°, respectively). Dogs with proximal shaft deformity represented a distinct group, which could not be identified using the magnitude of the TPS alone. Characterizing more precisely the shape of the proximal portion of the tibia in dogs contributes to our understanding of the pathogenesis of steep TPS and may facilitate the optimization of the surgical management of dogs with CCL rupture.
IMAGING FEATURES OF DISCOSPONDYLITIS IN TWO HORSES
Authors: SWEERS LYNELLE , CARSTENS ANN
Published: March 2006

Two horses with discospondylitis are described with emphasis on the imaging modalities used and their contribution to the final diagnosis and outcome. Radiographic findings were vertebral endplate lysis with sclerosis in both horses, with additional vertebral subluxation and ventral spondylosis in one horse. Ultrasonographic findings included vertebral malalignment and obliteration of the intervertebral disc by spondylotic bone in one horse and irregular endplates, a widened disc space, a hypoechoic paravertebral abscess and hypoechoic, atrophic adjacent musculature with loss of linear fiber pattern in the other horse. Bone scintigraphy excluded additional affected sites. A systematic approach is recommended when performing an ultrasound examination of the spine.
ACCURACY OF INCREASED THYROID ACTIVITY DURING PERTECHNETATE SCINTIGRAPHY BY SUBCUTANEOUS INJECTION FOR DIAGNOSING HYPERTHYROIDISM IN CATS
Authors: PAGE RICHARD B. , SCRIVANI PETER V. , DYKES NATHAN L. , ERB HOLLIS N. , HOBBS JEFF M.
Published: March 2006

Our purpose was to determine the accuracy of increased thyroid activity for diagnosing hyperthyroidism in cats suspected of having that disease during pertechnetate scintigraphy using subcutaneous rather than intravenous radioisotope administration. Increased thyroid activity was determined by two methods: the thyroid:salivary ratio (T:S) and visual inspection. These assessments were made on the ventral scintigram of the head and neck. Scintigraphy was performed by injecting sodium pertechnetate (111 MBq, SQ) in the right‐dorsal–lumbar region; static‐acquisition images were obtained 20 min after injection. We used 49 cats; 34 (69%) had hyperthyroidism based on serum‐chemistry analysis. Using a Wilcoxon's rank‐sum test, a significant difference (P<0.0001) was detected in the T:S between cats with and without hyperthyroidism. Using a decision criterion of 2.0 for the T:S, the test accurately predicted hyperthyroidism in 32/34 cats (sensitivity, 94%; 95% confidence interval (CI), 85–100%) and correctly predicted that hyperthyroidism was absent in 15/15 cats (specificity, 100%; CI, 97–100%). Using visual inspection, the test accurately predicted hyperthyroidism in 34/34 cats (sensitivity, 100%; CI, 99–100%) and correctly predicted that hyperthyroidism was absent in 12/15 cats (specificity, 80%; CI, 56–100%). The positive and negative predictive values were high for a wide range of prevalence of hyperthyroidism. And, the test had excellent agreement within and between examiners. Therefore, detecting increased thyroid activity during pertechnetate scintigraphy by subcutaneous injection is an accurate and reproducible test for feline hyperthyroidism.
EFFECT OF OBSERVER VARIABILITY ON GLOMERULAR FILTRATION RATE MEASUREMENT BY RENAL SCINTIGRAPHY IN DOGS
Authors: KAMPA NARUEPON , LORD PETER , MARIPUU ENN
Published: March 2006

Observer variation in kidney depth measurement for correction of soft‐tissue attenuation and kidney region of interest (ROI) drawing was evaluated using 60 clinical dogs with a wide range of glomerular filtration rate (GFR) for their effect on the calculated percentage uptake of99mTc‐diethylenetriamine pentaacetic acid (DTPA) and individual kidney GFR by scintigraphy. Kidney depth was measured separately on the lateral image using two color tables: a threshold and a continuous red–green–blue. Within‐observer variability of the semi‐automatic ROI drawing of the estimated total GFR was up to 10% for the right kidney (RK) and 9% for the left kidney (LK). The variability was lower between observers, 6% for RK and 8% for LK. Manual ROI drawing caused more within observer variation than semi‐automatic: up to 14% for RK and 11% for LK. Continuous red–green–blue table caused more variation within and between observers than threshold table. Average within‐observer variability from both observers of kidney depth measurement on different color tables could vary up to 5.5% and 6.5% variation of the GFR of RK and LK, respectively. Most variation affecting the DTPA percentage uptake came from the ROI drawing technique. Variations of the method because of the effects of both kidney depth and kidney ROI drawing were up to 8% and 10% for RK and LK, respectively. To minimize these variations a threshold scale should be used for the kidney depth measurement and an automatic or semi‐automatic ROI should be used whenever possible. In sequential examinations the same person should make all the measurements.
PRELIMINARY EVALUATION OF99mTECHNETIUM DIETHYLENETRIAMINE PENTAACETIC ACID,99mTECHNETIUM DIMERCAPTOSUCCINIC ACID, AND99mTECHNETIUM MERCAPTOACETYLTRIGLYCINE FOR RENAL SCINTIGRAPHY IN CORN SNAKES (ELAPHE GUTTATA GUTTATA)
Authors: SYKES JOHN M. , SCHUMACHER JUERGEN , AVENELL JAMES , RAMSAY EDWARD , DANIEL GREGORY B.
Published: March 2006

The efficacy of three radiopharmaceuticals,99mTc‐diethylenetriaminepentaacetic acid (99mTc‐DTPA),99mTc‐dimercaptosuccinic acid (99mTc‐DMSA), and99mTc‐mercaptoacetyltriglycine (99mTc‐MAG3), for renal imaging was examined in 16 corn snakes (Elaphe guttata guttata). All snakes received the radiopharmaceutical via an intracardiac injection. The kidneys could not be visualized in the three snakes that received99mTc‐DTPA or in the three snakes that received99mTc‐DMSA, but were well delineated in all 10 snakes receiving99mTc‐MAG3. These snakes were anesthetized and a dynamic frame mode acquisition was obtained for 30 min immediately following injection. A 60 s single static frame mode image was then obtained with the snake in a curled position. Two of the 10 snakes that received99mTc‐MAG3were removed from further analysis because of suspected pericardial injections. Of the remaining eight snakes, the mean (±SD) renal uptake was 25±9.8% or 24±9.7%, with or without correction for residual injection site activity, respectively. Correction for remaining radioactivity in the heart does not appear to be necessary if it is less than 10% of the total dose.99mTc‐MAG3provided consistently high quality images of the kidneys and further studies are warranted to evaluate its sensitivity for detecting decreased function in snakes with renal disease.
IOHEXOL PLASMA CLEARANCE IN HEALTHY DOGS AND CATS
Authors: GOY‐THOLLOT ISABELLE , CHAFOTTE CAROLINE , BESSE STÉPHANE , GARNIER FRANÇOIS , BARTHEZ PAUL Y.
Published: March 2006

Iohexol plasma clearance as a measure of glomerular filtration was determined in 31 dogs and 19 cats after an intravenous (IV) bolus injection. All animals were healthy and privately owned. Serial blood samples were taken before and up to 4 h after tracer injection. Iohexol plasma concentration was determined using X‐ray fluorescence. A plasma tracer elimination curve was generated and clearance was calculated by dividing the injected dose by the area under the curve estimated using a two‐compartment pharmacological model. Clearance was normalized to body weight (BW), body surface area (BSA), and extracellular fluid volume (ECFV). Mean, SD, and coefficient of variation of plasma clearance, before and after normalization, were calculated. Linear regression analyses were performed between body size and normalized plasma clearances. No significant linear relation was found between BSA and clearance normalized to BSA in dogs, and between BSA, BW, ECFV and clearance normalized to BSA, BW, and ECFV in cats. The optimal method for normalization of iohexol plasma clearance in dogs was by using BSA. In cats, all three methods tested were considered satisfactory. Normalization to BSA appears to be superior to normalization to BW and ECFV in dogs, and can be recommended for clinical use.
Everyday Activity Settings, Natural Learning Environments, and Early Intervention Practices
Authors: Dunst Carl J. , Bruder Mary Beth , Trivette Carol M. , Hamby Deborah W.
Published: March 2006

Abstract Findings from two studies examining the parent and child outcomes associated with different ways of conceptualizing natural learning environment early intervention practices are presented. One sample in each study was asked to indicate the extent to which early intervention practitioners implemented their interventions in everyday family or community activities, and one sample in each study was asked to indicate the extent to which everyday family or community activities were used as sources of child learning opportunities. Results from both studies showed that using everyday activities as sources of children's learning opportunities were associated with positive benefits, whereas practitioners’ implementing their interventions in everyday activities showed little or no positive benefits, and in several cases, had negative consequences. Results are discussed in terms of the need to carefully consider how and in what manner natural learning environment practices are operationalized by early intervention practitioners.
The Learn at Play Program (LAPP): Merging Family, Developmental Research, Early Intervention, and Policy Goals for Children with Down Syndrome
Authors: Iarocci Grace , Virji‐Babul Naznin , Reebye Pratibha
Published: March 2006

Abstract This article addresses the dynamics of parent–child interactions and their potential influence on the development of social competence among children with Down syndrome (DS). The authors argue that a strong parent–child relationship is fundamental for building the social competence of children with DS and the integration and inclusion of these children into their communities. The Learn at Play Program (LAPP), a model of early intervention that prioritizes the goals of nurturing and shaping the development of interpersonal skills and social competence among children with DS, is proffered. Discussed first is a brief overview of early intervention and the rationale for the need to focus on parent–child interactions and social competence when DS is present. The LAPP early intervention model for children with DS and their families is presented along with data from seven mother–child dyads assessed with the LAPP longitudinal study of parent–child interactions in DS to demonstrate the use of the model. The author's experiences with the LAPP program are also used to illustrate the utility of linking supportive networks (such as nonprofit organizations), academic and provincial government funding partnerships and public policy forums, and publicly funded organizations providing services to children with developmental delays from birth to 3 years old.
Professional Training in Early Intervention: A European Perspective
Authors: Pretis Manfred
Published: March 2006

Abstract Professional training in early childhood intervention (ECI), particularly additional certificates, degrees, or continuing education, is currently a major topic within European working groups. The complexity of ECI, including medical, pedagogical, psychological, and social involvement, the need for both family‐ and child‐centered work, and the child's young age require professional skills that normally exceed standard professional training in the field. This article focuses on current efforts to define a “common ground” of ECI, focusing on the competencies and skills needed for successful early intervention. Common ground issues focus on personal competencies, the knowledge base, joining the family, individual intervention methods, and team‐related activities. The author concludes that there is a strong need for a common professional ground in terms of philosophy, ethics, comparable standards, and evidence‐based intervention methods. Recent European efforts have been focusing on this common ground by designing a common “passport on the professional training” in ECI.
Patterns of Engagement in Young Children with and without Developmental Delay
Authors: Almqvist Lena
Published: March 2006

Abstract  The purpose of this study was to identify patterns of process characteristics capturing the essence of children's experiences in their natural environment and their possible association with health and well‐being operationalized as engagement for young children with and without developmental delay. Data were gathered from 1035 children between 1 and 3 years in community‐based preschools. Teachers and parents responded to questionnaires concerning interaction, activity, and engagement, as well as demographic and biopsychosocial information. A cluster analysis was conducted to find homogenous patterns related to engagement. Five distinct patterns were identified, all related to different levels of engagement. Several factors, within both the child and the environment, were associated with high levels of engagement. Interaction skills and availability of activities appear to be strong predictors of high‐level engagement, regardless whether or not the child has been identified as developmentally delayed.
Evidence Base for Practice: Reduction of Restraint and Seclusion Use During Child and Adolescent Psychiatric Inpatient Treatment
Authors: Delaney Kathleen R.
Published: March 2006

Background: Restraint and seclusion of children has great potential for harm. Since the mid‐1980s, psychiatric inpatient personnel for children and adolescents have put considerable energy in reducing the use of extreme measures of aggression management. While the use of restraints is a particular problem in the United States, aggression management and means of control in psychiatric settings is an international issue.

Approach: The core question of this review was: What is the current state of the evidence supporting restraint reduction efforts with children and adolescents? Studies were reviewed and critiqued that related to programs of restraint reduction, restraint reduction methods, and aggression management. Internationally, there seems to be more emphasis on reducing coercive measures by understanding the context of their use. Thus, studies exploring staff perceptions and decisions concerning coercive measures were also examined.

Findings: The evidence supporting restraint reduction methods in the United States comes mainly from case study reports of clinical sites' quality improvement projects. Consequently, a collection of studies is accumulating that supports a multi‐strategy approach to restraint reduction. Limited evidence exists for aggression management measures and training in de‐escalation techniques. Controversial aggression management techniques such as the use of pro re nata medication and holding continue to be used with very little support for their efficacy.

Recommendations: Recommendations include taking a view of restraint and seclusion as emergency measures to address dangerous aggression, not interventions examined in controlled studies. As such it is suggested that sites pool data on restraint use and reduction efforts to create a database for benchmarking and studying variations among hospitals. Furthermore, attention should also be given to developing additional means for addressing aggressive behaviors.

Worldviews on Evidence‐Based Nursing 2006; 3(1):19‐30
Evidence of Dichogamy in Santalum album L.
Authors: Ma Guo‐Hua , Bunn Eric , Zhang Jing‐Feng , Wu Guo‐Jiang
Published: March 2006

Flowering, fruit set, embryological development, and pollination trials were investigated in Santalum album L. Each ovary may have three to four ovules. Microsporogenesis and megasporogenesis in the same flower were synchronized at the earlier stages of flower development. However, at anthesis, when pollen was mature, the magaspore had developed only to the stage of a one‐ to two‐nucleus embryo sac. As the eight‐nucleus embryo sac developed, some mamelon cells began to undergo programmed cell death, forming holes into which the eight‐nucleus embryo sacs extended, becoming “N” or “S” shaped. The development from a two‐nucleus embryo sac to a matured eight‐nucleus embryo sac lasted up to 10 d. Fruit‐set from open pollination was less than 2%. The endosperm develops prior to division of the zygotic embryo and one to three embryos and endosperms were formed in the same fruit. A mature seed usually germinates to produce one seedling; however, two and three seedlings from one seed were also observed, albeit at a low frequency. Pollination trials showed that no seed sets when inflorescences were covered with a bag; however, artificial pollination could improve fruit set. Our pollination trials and embryological studies proved that the flower of S. album is dichogamous and fruit set has high heterozygosity.

(Managing editor: Wei Wang)
Differentiation of a Miniature Inverted Transposable Element (MITE) System in Asian Rice Cultivars and Its Inference for a Diphyletic Origin of Two Subspecies of Asian Cultivated Rice
Authors: Hu Hao , Mu Jie , Zhang Hong‐Ji , Tao Yue‐Zhi , Han Bin
Published: March 2006

In the present study, we report a survey on a Miniature Inverted Transposable Element (MITE) system known as mPing in 102 varieties of Asian cultivated rice (Oryza sativa L.). We found that mPing populations could be generalized into two families, mPing‐1 and mPing‐2, according to their sequence structures. Further analysis showed that these two families of mPing had significant bias in their distribution pattern in two subspecies of rice, namely O. sativa ssp. japonica and indica. O. sativa japonica has a higher proportion of mPing‐1 as a general trait, whereas O. sativa indica has a higher proportion of mPing‐2. We also examined the mPing system in a doubled haploid (DH) cross‐breeding population of jingxi 17 (japonica) and zhaiyeqing 8 (indica) varieties and observed that the mPing system was not tightly linked to major subspecies‐determining genes. Furthermore, we checked the mPing system in 28 accessions of Asian common wild rice O. rufipogon and found the mPing system in O. rufipogon. The distribution pattern of the mPing system in O. rufipogon indicated a diphyletic origin of the Asian cultivated rice O. sativa species. We did not find the mPing system in another 20 Oryza species. These results substantiated a previous hypothesis that O. rufipogon and O. nivara species were the closest relatives of O. sativa and that the two extant subspecies of O. sativa were evolved independently from corresponding ecotypes of O. rufipogon.

(Managing editor: Li‐Hui Zhao)
The role of nitric oxide in the peripheral vasoconstriction caused by human placental lactogen in anaesthetized pigs
Authors: Molinari C. , Grossini E. , Mary D. A. S. G. , Ribichini F. , Surico N. , Vacca G.
Published: March 2006

Regional intra‐arterial infusion of human placental lactogen in anaesthetized pigs has been shown to cause coronary, renal and iliac vasoconstriction by antagonizing the vasodilatory effects of β2‐adrenergic receptors. Since nitric oxide is known to modulate or mediate β2‐adrenergic effects, the present study was planned in the same experimental model to determine the role of nitric oxide in the above vascular responses to human placental lactogen. In eight pigs anaesthetized with sodium pentobarbitone, changes in anterior descending coronary, left renal and left internal iliac blood flow caused by intra‐arterial infusion of human placental lactogen at constant heart rate and arterial blood pressure were assessed using electromagnetic flowmeters. Intra‐arterial infusion of the human placental lactogen caused decreases in coronary, renal and iliac blood flow which, respectively, averaged 16.7, 8.1 and 12.2% of the baseline values. The role of nitric oxide in this response was studied in the same pigs by repeating the experiments, after measured blood flows had returned to baseline values, following intra‐arterial administration of Nω‐nitro‐l‐arginine methyl ester (l‐NAME). The subsequent intra‐arterial infusion of human placental lactogen did not cause any significant changes in measured blood flows, even when performed after reversing the increase in arterial blood pressure and coronary, renal and iliac resistance caused by l‐NAME with continuous intravenous infusion of papaverine. These results indicate that the coronary, renal and iliac vasoconstriction caused by human placental lactogen, known to involve antagonism of β2‐adrenergic vasodilatory effects, was mediated by inhibition of nitric oxide release.
Experimental and Computational Investigation of Flow Development and Pressure Drop in a Rectangular Micro-channel
Authors: Qu Weilin , Mudawar Issam , Lee Sang-Youp , Wereley Steven T.
Published: March 2006

Flow development and pressure drop were investigated both experimentally and computationally for adiabatic single-phase water flow in a single 222μm wide, 694μm deep, and 12cm long rectangular micro-channel at Reynolds numbers ranging from 196 to 2215. The velocity field was measured using a micro-particle image velocimetry system. A three-dimensional computational model was constructed which provided a detailed description of liquid velocity in both the developing and fully developed regions. At high Reynolds numbers, sharp entrance effects produced pronounced vortices in the inlet region that had a profound influence on flow development downstream. The computational model showed very good predictions of the measured velocity field and pressure drop. These findings prove the conventional Navier-Stokes equation accurately predicts liquid flow in micro-channels, and is therefore a powerful tool for the design and analysis of micro-channel heat sinks intended for electronic cooling.
Thermal Joint Resistance of Polymer-Metal Rough Interfaces
Authors: Bahrami M. , Yovanovich M. M. , Marotta E. E.
Published: March 2006

A compact analytical model is proposed for predicting thermal joint resistance of rough polymer-metal interfaces in a vacuum. The model assumes plastic deformation at microcontacts and joint temperatures less than the polymer’s glassy temperature. The joint resistance includes two components: (i) bulk resistance of the polymer, and (ii) microcontacts resistance, i.e., constriction∕spreading resistance of the microcontacts at the interface. Performing a deformation analysis, it is shown that the deformation mode of surface asperities is plastic for most polymers studied. It is observed that the thermophysical properties of the polymer control the thermal joint resistance and the metallic surface properties have a second order effect on the thermal joint resistance. A new nondimensional parameter, the ratio of microcontacts over bulk thermal resistances, is proposed as a criterion to specify the relative importance of the microcontacts thermal resistance. The present model is compared with more than 140 experimental data points collected for a selected number of polymers. The averaged rms relative difference between the model and data is approximately 12.7%.
Applicability of ACR breast dosimetry methodology to a digital mammography system
Authors: Tomon John J. , Johnson Thomas E. , Swenson Kristin N. , Schauer David A.
Published: March 2006

Determination of mean glandular dose (MGD) to breast tissue is an essential aspect of mammography equipment evaluations and exposure controls. The American College of Radiology (ACR) Quality Control Manual outlines the procedure for MGD determination in screen‐film mammography based upon conversions of entrance skin exposures (ESEs) measured with an ionization chamber (IC). The development of digital mammography has increased with the demand for improved object resolution and tissue contrast. This change in image receptor from screen‐film to a solid‐state detector has led to questions about the applicability of the ACR MGD methodology to digital mammography. This research has validated the applicability of the ACR MGD methodology to digital mammography in the GE digital mammography system Senographe . MGD was determined using light output measurements from thermoluminescent dosimeters , exposure measurements from an IC and conversion factors from the ACR Mammography Quality Control Manual. and data indicate that there is a statistically significant difference between the two measurements with the Senographe . However, the applicability of the ACR's methodology was validated by calculating MGD at various depths in a breast phantom. Additionally, the results of backscatter measurements from the image receptors of both mammography modalities indicate there is a difference (all values ) in the radiation backscattered from each image receptor.
Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study
Authors: Li Tianfang , Liang Zhengrong , Singanallur Jayalakshmi V. , Satogata Todd J. , Williams David C. , Schulte Reinhard W.
Published: March 2006

Proton computed tomography (pCT) has been explored in the past decades because of its unique imaging characteristics, low radiation dose, and its possible use for treatment planning and on‐line target localization in proton therapy. However, reconstruction of pCT images is challenging because the proton path within the object to be imaged is statistically affected by multiple Coulomb scattering. In this paper, we employ GEANT4‐based Monte Carlo simulations of the two‐dimensional pCT reconstruction of an elliptical phantom to investigate the possible use of the algebraic reconstruction technique (ART) with three different path‐estimation methods for pCT reconstruction. The first method assumes a straight‐line path (SLP) connecting the proton entry and exit positions, the second method adapts the most‐likely path (MLP) theoretically determined for a uniform medium, and the third method employs a cubic spline path (CSP). The ART reconstructions showed progressive improvement of spatial resolution when going from the SLP [2 line pairs (lp) ] to the curved CSP and MLP path estimates . The MLP‐based ART algorithm had the fastest convergence and smallest residual error of all three estimates. This work demonstrates the advantage of tracking curved proton paths in conjunction with the ART algorithm and curved path estimates.
Altruistic Helping in Human Infants and Young Chimpanzees
Authors: Warneken Felix , Tomasello Michael
Published: March 2006

Human beings routinely help others to achieve their goals, even when the helper receives no immediate benefit and the person helped is a stranger. Such altruistic behaviors (toward non-kin) are extremely rare evolutionarily, with some theorists even proposing that they are uniquely human. Here we show that human children as young as 18 months of age (prelinguistic or just-linguistic) quite readily help others to achieve their goals in a variety of different situations. This requires both an understanding of others' goals and an altruistic motivation to help. In addition, we demonstrate similar though less robust skills and motivations in three young chimpanzees.
Synthesis and Characterization of the Nitrides of Platinum and Iridium
Authors: Crowhurst Jonathan C. , Goncharov Alexander F. , Sadigh Babak , Evans Cheryl L. , Morrall Peter G. , Ferreira James L. , Nelson A. J.
Published: March 2006

Transition metal nitrides are of great technological and fundamental importance because of their strength and durability and because of their useful optical, electronic, and magnetic properties. We have evaluated a recently synthesized platinum nitride (PtN) that was shown to have a large bulk modulus, and we propose a structure that is isostructural with pyrite and has the stoichiometry PtN
2
. We have also synthesized a recoverable nitride of iridium under nearly the same conditions of pressure and temperature as PtN
2
. Although it has the same stoichiometry, it exhibits much lower structural symmetry. Preliminary results suggest that the bulk modulus of this material is also very large.
Chemical Rescue of a Mutant Enzyme in Living Cells
Authors: Qiao Yingfeng , Molina Henrik , Pandey Akhilesh , Zhang Jin , Cole Philip A.
Published: March 2006

The restoration of catalytic activity to mutant enzymes by small molecules is well established for in vitro systems. Here, we show that the protein tyrosine kinase Src arginine-388→alanine (R388A) mutant can be rescued in live cells with the use of the small molecule imidazole. Cellular rescue of a viral Src homolog was rapid and reversible and conferred predicted oncogenic properties. Using chemical rescue in combination with mass spectrometry, we confirmed six known Src kinase substrates and identified several new protein targets. Chemical rescue data suggest that cellular Src is active under basal conditions. Rescue of R388A cellular Src provided insights into the mitogen-activated protein kinase pathway. This chemical rescue approach will likely have many applications in cell signaling.
Architecture of a Fungal Fatty Acid Synthase at 5 Å Resolution
Authors: Jenni Simon , Leibundgut Marc , Maier Timm , Ban Nenad
Published: March 2006

All steps of fatty acid synthesis in fungi are catalyzed by the fatty acid synthase, which forms a 2.6-megadalton α
6
β
6
complex. We have determined the molecular architecture of this multienzyme by fitting the structures of homologous enzymes that catalyze the individual steps of the reaction pathway into a 5 angstrom x-ray crystallographic electron density map. The huge assembly contains two separated reaction chambers, each equipped with three sets of active sites separated by distances up to ∼130 angstroms, across which acyl carrier protein shuttles substrates during the reaction cycle. Regions of the electron density arising from well-defined structural features outside the catalytic domains separate the two reaction chambers and serve as a matrix in which domains carrying the various active sites are embedded. The structure rationalizes the compartmentalization of fatty acid synthesis, and the spatial arrangement of the active sites has specific implications for our understanding of the reaction cycle mechanism and of the architecture of multienzymes in general.
Auxiliary Subunits Assist AMPA-Type Glutamate Receptors
Authors: Nicoll Roger A. , Tomita Susumu , Bredt David S.
Published: March 2006

Glutamate, the major excitatory neurotransmitter in the brain, acts primarily on two types of ionotropic receptors: α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and
N
-methyl-
d
-aspartate (NMDA) receptors. Work over the past decade indicates that regulated changes in the number of synaptic AMPA receptors may serve as a mechanism for information storage. Recent studies demonstrate that a family of small transmembrane AMPA receptor regulatory proteins (TARPs) controls both AMPA receptor trafficking and channel gating. TARPs provide the first example of auxiliary subunits of ionotropic receptors. Here we review the pivotal role that TARPs play in the life cycle of AMPA receptors.
Giant Electrocaloric Effect in Thin-Film PbZr
0.95
Ti
0.05
O
3
Authors: Mischenko A. S. , Zhang Q. , Scott J. F. , Whatmore R. W. , Mathur N. D.
Published: March 2006

An applied electric field can reversibly change the temperature of an electrocaloric material under adiabatic conditions, and the effect is strongest near phase transitions. We demonstrate a giant electrocaloric effect (0.48 kelvin per volt) in 350-nanometer PbZr
0.95
Ti
0.05
O
3
films near the ferroelectric Curie temperature of 222°C. A large electrocaloric effect may find application in electrical refrigeration.
Deities for Atheists
Authors: Shermer Michael
Published: March 2006

Civilized Life in the Universe
. Scientists on Intelligent Extraterrestrials.
By George Basalla
. Oxford University Press, Oxford, 2005. 247 pp. $29.95, £17.95. ISBN 0-19-517181-0.

Examining claims of scientists from Aristotle to Hawking, the author traces the cascading influence of speculation about the existence of civilized life on other planets.
The Spirit Rover's Athena Science Investigation at Gusev Crater, Mars
Authors: Squyres S. W. , Arvidson R. E. , Bell J. F. , Brückner J. , Cabrol N. A. , Calvin W. , Carr M. H. , Christensen P. R. , Clark B. C. , Crumpler L. , Des Marais D. J. , d'Uston C. , Economou T. , Farmer J. , Farrand W. , Folkner W. , Golombek M. , Gorevan S. , Grant J. A. , Greeley R. , Grotzinger J. , Haskin L. , Herkenhoff K. E. , Hviid S. , Johnson J. , Klingelhöfer G. , Knoll A. , Landis G. , Lemmon M. , Li R. , Madsen M. B. , Malin M. C. , McLennan S. M. , McSween H. Y. , Ming D. W. , Moersch J. , Morris R. V. , Parker T. , Rice J. W. , Richter L. , Rieder R. , Sims M. , Smith M. , Smith P. , Soderblom L. A. , Sullivan R. , Wänke H. , Wdowiak T. , Wolff M. , Yen A.
Published: March 2006

The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. Gusev is hypothesized to be the site of a former lake, but no clear evidence for lacustrine sedimentation has been found to date. Instead, the dominant lithology is basalt, and the dominant geologic processes are impact events and eolian transport. Many rocks exhibit coatings and other characteristics that may be evidence for minor aqueous alteration. Any lacustrine sediments that may exist at this location within Gusev apparently have been buried by lavas that have undergone subsequent impact disruption.
Textures of the Soils and Rocks at Gusev Crater from Spirit's Microscopic Imager
Authors: Herkenhoff K. E. , Squyres S. W. , Arvidson R. , Bass D. S. , Bell J. F. , Bertelsen P. , Cabrol N. A. , Gaddis L. , Hayes A. G. , Hviid S. F. , Johnson J. R. , Kinch K. M. , Madsen M. B. , Maki J. N. , McLennan S. M. , McSween H. Y. , Rice J. W. , Sims M. , Smith P. H. , Soderblom L. A. , Spanovich N. , Sullivan R. , Wang A.
Published: March 2006

The Microscopic Imager on the Spirit rover analyzed the textures of the soil and rocks at Gusev crater on Mars at a resolution of 100 micrometers. Weakly bound agglomerates of dust are present in the soil near the Columbia Memorial Station. Some of the brushed or abraded rock surfaces show igneous textures and evidence for alteration rinds, coatings, and veins consistent with secondary mineralization. The rock textures are consistent with a volcanic origin and subsequent alteration and/or weathering by impact events, wind, and possibly water.
Novel Partial Reductive Pathway for 4-Chloronitrobenzene and Nitrobenzene Degradation inComamonassp. Strain CNB-1
Authors: Wu Jian-feng , Jiang Cheng-ying , Wang Bao-jun , Ma Ying-fei , Liu Zhi-pei , Liu Shuang-jiang
Published: March 2006

Comamonassp. strain CNB-1 grows on 4-chloronitrobenzene (4-CNB) and nitrobenzene as sole carbon and nitrogen sources. In this study, two genetic segments,cnbB-orf2-cnbAandcnbR-orf1-cnbCaCbDEFGHI, located on a newly isolated plasmid, pCNB1 (ca. 89 kb), and involved in 4-CNB/nitrobenzene degradation, were characterized. Seven genes (cnbA,cnbB,cnbCa,cnbCb,cnbD,cnbG, andcnbH) were cloned and functionally expressed in recombinantEscherichia coli, and they were identified as encoding 4-CNB nitroreductase (CnbA), 1-hydroxylaminobenzene mutase (CnbB), 2-aminophenol 1,6-dioxygenase (CnbCab), 2-amino-5-chloromuconic semialdehyde dehydrogenase (CnbD), 2-hydroxy-5-chloromuconic acid (2H5CM) tautomerase, and 2-amino-5-chloromuconic acid (2A5CM) deaminase (CnbH). In particular, the 2A5CM deaminase showed significant identities (31 to 38%) to subunit A of Asp-tRNAAsn/Glu-tRNAGlnamidotransferase and not to the previously identified deaminases for nitroaromatic compound degradation. Genetic cloning and expression ofcnbHinEscherichia colirevealed that CnbH catalyzed the conversion of 2A5CM into 2H5CM and ammonium. Four other genes (cnbR,cnbE,cnbF, andcnbI) were tentatively identified according to their high sequence identities to other functionally identified genes. It was proposed that CnbH might represent a novel type of deaminase and be involved in a novel partial reductive pathway for chloronitrobenzene or nitrobenzene degradation.
Human and Animal Enteric Caliciviruses in Oysters from Different Coastal Regions of the United States
Authors: Costantini Veronica , Loisy Fabienne , Joens Lynn , Le Guyader Françoise S. , Saif Linda J.
Published: March 2006

Food-borne diseases are a major cause of morbidity and hospitalization worldwide. Enteric caliciviruses are capable of persisting in the environment and in the tissues of shellfish. Human noroviruses (HuNoVs) have been implicated in outbreaks linked to shellfish consumption. The genetic and antigenic relatedness between human and animal enteric caliciviruses suggests that interspecies transmission may occur. To determine the occurrence of human and animal enteric caliciviruses in United States market oysters, we surveyed regional markets. Oysters were collected from 45 bays along the United States coast during the summer and winter of 2002 and 2003. Samples were analyzed by reverse transcription-PCR, and results were confirmed by hybridization and sequence analysis. Nine samples (20%) were positive for HuNoV genogroup II after hybridization. Animal enteric caliciviruses were detected in 10 samples (22%). Seven of these samples were positive for porcine norovirus genogroup II, and one sample was positive for porcine sapovirus after hybridization and confirmation by sequencing. Bovine noroviruses were detected in two samples, and these results were confirmed by sequencing. Five HuNoV samples sequenced in the polymerase region were similar to the norovirus genogroup II US 95/96 subset (genogroup II-4) previously implicated in diarrhea outbreaks. Different seasonal and state distributions were detected. The presence of animal enteric caliciviruses was associated with states with high livestock production. Although the presence of human caliciviruses in raw oysters represents a potential risk for gastroenteritis, disease confirmation by investigation of outbreaks is required. The simultaneous detection of human and animal enteric caliciviruses raises concerns about human infection or coinfection with human and animal strains that could result in genomic recombination and the emergence of new strains.