bluuebunny/crossref_metadata_2025 huggingface dataset:
GREEN AUTOFLUORESCENCE OF DINOFLAGELLATE CYSTS CAN BE USED INSTEAD OF PRIMULINE STAINING FOR CYST VISUALIZATION AND ENUMERATION IN SEDIMENTS1
Authors: Tang Ying Zhong , Dobbs Fred C.
Published: February 2007

Primuline staining is widely used to visualize and enumerate dinoflagellate cysts in marine sediments. In staining cysts of Gymnodinium catenatum H. W. Graham, Scrippsiella trochoidea (F. Stein) A. R. Loebl., and cysts from estuarine sediments, we found their green fluorescence after primuline treatment to be seemingly no different from the green autofluorescence (GAF) inherent in vegetative cells and cysts of dinoflagellates fixed in formaldehyde. Although primuline subsequently proved to enhance green fluorescence of both species quantitatively, we nonetheless recommend taking advantage of dinoflagellates' GAF to detect and count their cysts in sediments. Doing so will reduce the time, chemical consumption, and possible loss of cells involved in the primuline‐staining procedure.
DISTRIBUTION, PHYLOGENY, AND GROWTH OF COLD‐ADAPTED PICOPRASINOPHYTES IN ARCTIC SEAS1
Authors: Lovejoy Connie , Vincent Warwick F. , Bonilla Sylvia , Roy Suzanne , Martineau Marie‐Josée , Terrado Ramon , Potvin Marianne , Massana Ramon , Pedrós‐Alió Carlos
Published: February 2007

Our pigment analyses from a year‐long study in the coastal Beaufort Sea in the western Canadian Arctic showed the continuous prevalence of eukaryotic picoplankton in the green algal class Prasinophyceae. Microscopic analyses revealed that the most abundant photosynthetic cell types wereMicromonas‐like picoprasinophytes that persisted throughout winter darkness and then maintained steady exponential growth from late winter to early summer. AMicromonas(CCMP2099) isolated from an Arctic polynya (North Water Polynya between Ellesmere Island and Greenland), an ice‐free section, grew optimally at 6°C–8°C, with light saturation at or below 10 μmol photons·m−2·s−1at 0°C. The 18S rDNA analyses of this isolate and environmental DNA clone libraries from diverse sites across the Arctic Basin indicate that this single psychrophilicMicromonasecotype has a pan‐Arctic distribution. The 18S rDNA from two other picoprasinophyte genera was also found in our pan‐Arctic clone libraries:BathycoccusandMantoniella. The ArcticMicromonasdiffered from genotypes elsewhere in the World Ocean, implying that the Arctic Basin is a marine microbial province containing endemic species, consistent with the biogeography of its macroorganisms. The prevalence of obligate low‐temperature, shade‐adapted species in the phytoplankton indicates that the lower food web of the Arctic Ocean is vulnerable to ongoing climate change in the region.
LIPID, FATTY ACID, AND STEROL COMPOSITION OF EIGHT SPECIES OF KARENIACEAE (DINOPHYTA): CHEMOTAXONOMY AND PUTATIVE LIPID PHYCOTOXINS1
Authors: Mooney Ben D. , Nichols Peter D. , De Salas Miguel F. , Hallegraeff Gustaaf M.
Published: February 2007

The lipid class, fatty acid, and sterol composition of eight species of ichthyotoxic marine gymnodinioid dinoflagellate (Karenia, Karlodinium, and Takayama) species was examined. The major lipid class in all species was phospholipid (78%–95%), with low levels of triacylglycerol (TAG; 0%–16%) and free fatty acid (FFA; 1%–11%). The common dinoflagellate polyunsaturated fatty acids (PUFA), octadecapentaenoic acid (OPA 18:5ω3), and docosahexaenoic acid (DHA 22:6ω3), were present in all species in varying amounts (14%–35% and 8%–23%, respectively). The very‐long‐chain PUFA (VLC‐PUFA) 28:7ω6 and 28:8ω3 were present at low levels (<1%), and the ratio of these fatty acids may be a useful chemotaxonomic marker at the species level. The typical dinoflagellate sterol dinosterol was absent from all species tested. A predominance of the 4‐methyl and 4‐desmethyl Δ8(14) sterols in all dinoflagellate species included 23‐methyl‐27‐norergosta‐8(14),22‐dien‐3β‐ol (Karenia papilionacea A. J. Haywood et Steid, 59%–66%); 27‐nor‐(24R)‐4α‐methyl‐5α‐ergosta‐8(14),22‐dien‐3β‐ol, brevesterol, (Takayama tasmanica de Salas, Bolch et Hallegraeff 84%, Takayama helix de Salas, Bolch, Botes et Hallegraeff 71%, Karenia brevis (C. C. Davis) G. Hansen et Moestrup 45%, Karlodinium KDSB01 40%, Karenia mikimotoi (Miyake et Kominami ex Oda) G. Hansen et Moestrup 38%); and (24R)‐4α‐methyl‐5α‐ergosta‐8(14),22‐dien‐3β‐ol, gymnodinosterol, (K. mikimotoi 48%, Karenia umbella de Salas, Bolch et Hallegraeff 59%, Karlodinium veneficum (D. L. Ballant.) J. Larsen 71%–83%). In Takayama species, five steroid ketones were identified, including for the first time the 3‐keto form of brevesterol and gymnodinosterol. These results indicate a biochemical link between sterol and steroid ketone biosynthesis, suggesting that selected dinoflagellates can make a significant contribution to ketones in marine sediments. The presence of steroid ketones, specific sterols, and fatty acids, and the ratio of VLC‐PUFA may prove to be a useful chemotaxonomic tool for distinguishing between morphologically similar species. The relative levels of the PUFA, OPA, and DHA, coupled with the potential inhibitory action of Δ8(14) sterols, may provide an insight into the ichthyotoxicity of these bloom‐forming dinoflagellates.
Pulsed Radiofrequency in Lumbar Radicular Pain: Clinical Effects in Various Etiological Groups
Authors: Abejón David , Garcia‐del‐Valle Santiago , Fuentes María Lorenza , Gómez‐Arnau Juan Ignacio , Reig Enrique , Van Zundert Jan
Published: February 2007

Background:  The purpose of this study was to evaluate the effectiveness of pulsed radiofrequency (PRF) applied to the lumbar dorsal root ganglion (DRG).

Methods:  A retrospective analysis of 54 consecutive patients who underwent 75 PRF procedures was performed. The patients were divided into three groups according to the etiology of the lesion (herniated disc [HD], spinal stenosis [SS], and failed back surgery syndrome [FBSS]). The analgesic efficacy of the technique was assessed using a 10‐point Numeric Rating Scale (NRS) at baseline and, along with the Global Perceived Effect (GPE), at 30, 60, 90, and 180 days. The reduction in medications and the number of complications associated with the technique were assessed.

Results:  A decrease in the NRS score was observed in patients with HD (P < 0.05) and SS (P < 0.001), but not in those with FBSS. The GPE scores confirmed this finding. No complications were noted.

Conclusions:  We observed that PRF of the DRG was significantly more efficacious in HD and SS than in FBSS patients. The application of PRF was not effective in FBSS.
Oral Ketamine for the Treatment of Type I Complex Regional Pain Syndrome
Authors: Villanueva‐Perez Vicente L. , Cerdá‐Olmedo German , Samper Juan Marcos Asensio , Mínguez Ana , Monsalve Vicente , Bayona Maria Jose , De Andrés Jose A.
Published: February 2007

Abstract: Ketamine has been shown to be effective in the treatment of neuropathic pain. We present a case of severe complex regional pain syndrome type 1 that was treated with oral ketamine. The response and tolerability of this preparation suggest that further study is warranted.
Medical Screening for Red Flags in the Diagnosis and Management of Musculoskeletal Spine Pain
Authors: Sizer Phillip S. , Brismée Jean‐Michel , Cook Chad
Published: February 2007

Abstract:  When a patient presents with pain in the different regions of the spine, the clinician executes a region‐appropriate basic examination that includes appropriate historical cues and specific physical examination tests that can be used to identify red flags. The clinical tests include a specific examination of the sensory and motor systems. Test outcomes are best interpreted in context with the entire examination profile, where the sensitivity and specificity of these tests can influence their utility in uncovering red flags. These red flags can be categorized based on the nature and severity or the specific elements of the patient’s presentation. Many general red flags can be observed in any region of the spine, while specific red flags must be categorized and discussed for each spinal region. This categorization can guide the clinician in the direction of management, whether that management is aimed at redirecting the patient’s care to another specialist, reconsidering the presentation and observing for clusters of findings that may suggest red flags, or managing the patient within the clinician’s specialty in context with the severity of the patient’s presentation.
Preference for Nature in Urbanized Societies: Stress, Restoration, and the Pursuit of Sustainability
Authors: Van Den Berg Agnes E. , Hartig Terry , Staats Henk
Published: February 2007

Urbanicity presents a challenge for the pursuit of sustainability. High settlement density may offer some environmental, economic, and social advantages, but it can impose psychological demands that people find excessive. These demands of urban life have stimulated a desire for contact with nature through suburban residence, leading to planning and transportation practices that have profound implications for the pursuit of sustainability. Some might dismiss people's desire for contact with nature as the result of an anti‐urban bias in conjunction with a romantic view of nature. However, research in environmental psychology suggests that people's desire for contact with nature serves an important adaptive function, namely, psychological restoration. Based on this insight, we offer a perspective on an underlying practical challenge: designing communities that balance settlement density with satisfactory access to nature experience. We discuss research on four issues: how people tend to believe that nature is restorative; how restoration needs and beliefs shape environmental preferences; how well people actually achieve restoration in urban and natural environments; and how contact with nature can promote health. In closing, we consider urban nature as a design option that promotes urban sustainability.
Normative, Gain and Hedonic Goal Frames Guiding Environmental Behavior
Authors: Lindenberg Siegwart , Steg Linda
Published: February 2007

This article discusses new developments about goal‐dependent framing and multiple goal frames (sometimes also called “multiple motives”), which are highly relevant for understanding environmental behavior. We introduce goal‐framing theory, which postulates that goals “frame” the way people process information and act upon it. Three goal frames are distinguished: a hedonic, gain, and normative goal frame. In general, multiple goals are active at any given time, which may (or may not) be compatible; that is, the strength of the focal goal may be influenced by other goals that are in the background. Based on an extensive review of studies in environmental psychology, we suggest those conditions under which each goal frame may be dominant in influencing environmental behavior. In the environmental context, normative goal frames imply acting pro‐environmentally, while gain and hedonic goal frames often result in not acting in an environmentally sound manner. Next, we argue that pro‐environmental behavior may be promoted by strengthening normative goals or by making gain and hedonic goals less incompatible with normative goals. Finally, based on goal‐framing theory, we suggest questions to be addressed in future research.
Travel Demand Management Targeting Reduced Private Car Use: Effectiveness, Public Acceptability and Political Feasibility
Authors: Gärling Tommy , Schuitema Geertje
Published: February 2007

The private car is fast, comfortable, and convenient. However, worldwide massive car use causes serious environmental problems. Although breakthroughs in clean automobile technology may be under way, reducing car use seems necessary in order to achieve a sustainable transportation system. Several travel demand management (TDM) measures have therefore been proposed and some have been implemented with this aim. The article reviews research addressing the question of how effective, acceptable to the public, and politically feasible such measures are. The conclusion is that noncoercive TDM measures alone are unlikely to be effective in reducing car use. Therefore, coercive TDM measures such as increasing cost for or prohibiting car use may be necessary but are difficult to implement because of public opposition and political infeasibility. If combined with noncoercive TDM measures providing attractive travel alternatives and communicating the benefits of car‐use reduction to the public, coercive TDM measures are likely to become more effective, acceptable, and politically feasible.
Environmental Psychology and Sustainable Development: Expansion, Maturation, and Challenges
Authors: Gifford Robert
Published: February 2007

In this summary article, some advances of, the potential for, and challenges faced by environmental psychology as a contributor to sustainability science are outlined. In its first 40 years, it has evolved from a discipline primarily—but never solely—concerned with proximate architecture to one that adds concern with larger‐scale issues, particularly sustainability. This growth of interest has in turn led to increased interest within it in public policy, technology, cooperation with other disciplines, multilevel analyses of problems, the ingestion of new ideas, and concern with the health of the biotic and ecological world. Some challenges are that the central proponents of “sustainability science” itself have not acknowledged environmental psychology as a potential contributor, the field is comparatively young, that it needs to explore biotic and ecological issues more, needs to help discriminate facts from nonfacts about environmental problems, and needs to warn sustainability science about the daunting task of overcoming environmental numbness and self‐interest in individuals. Nevertheless, there is hope: sustainability scientists, including environmental psychologists, may be Adam Smith's “invisible hand.”
The Development of Practices for Action in Classroom Dyadic Interaction: Focus on Task Openings
Authors: HELLERMANN JOHN
Published: February 2007

This study is part of a larger research program investigating conversational practices that are resources for language learning in classroom settings. Using methods from conversation analysis, this analysis describes how low‐level adult learners' interactional competence in English develops through their interactional practices in a language classroom. The study isolates one context for a particular action in the language classroom: student dyads opening their teacher‐assigned tasks. The data come from interactions of six successful learners who participated in classes at the data collection site over a period of 18 to 27 months. The excerpts presented in this study show the same‐student dyads incorporating language from the teacher and from one another over time into their discursive practices to manage the openings of their dyadic interactions. The results provide evidence for the ongoing discussion (cf.Brouwer & Wagner, 2004;Markee & Kasper, 2004) on the nature of language learning and the ability of methods of conversation analysis to address the issue of learning.
Carnival in a Mainstream Kindergarten Classroom: A Bakhtinian Analysis of Second Language Learners' Off‐Task Behaviors
Authors: DaSILVA IDDINGS ANA CHRISTINA , McCAFFERTY STEVEN G.
Published: February 2007

This study explored Mikhail Bakhtin's conceptualization of carnival as it applies to 2 second language (L2) learners in an American kindergarten classroom. Unwilling to engage in two story retelling tasks, the children nevertheless invoked the imaginative, playful, and dialogic world of carnival, creating meaningful, contingent contexts for interaction in the L2. A third task, also originally thought to be representative of carnival, proved only to have carnival‐like features and did not lead to the sense of renewal associated with Bakhtin's interpretation of the state of mind of the festivals.
A Child's Development of Interactional Competence in a Swedish L2 Classroom
Authors: CEKAITE ASTA
Published: February 2007

This study explores a child's emergent second language (L2) interactional competence during her first year in a Swedish immersion classroom. Within the theoretical framework of situated learning, it focuses on how she acquires expertise in a specific classroom practice: multiparty classroom talk. The data cover three periods (the early, middle, and late phases) of her first school year. The methods adopted combine a microanalytic approach with ethnographic fieldwork analyses of L2 socialization within a classroom community. The analyses revealed systematic changes in the novice's interactional engagements. An interplay of language skills and turn‐taking skills influenced her participation in multiparty talk during the three periods, casting her as (a) a silent child, (b) a noisy and loud child, and (c) a skillful student. These changes indicate that learning cannot be seen as the unilinear development of a single learner identity. It is argued that a detailed longitudinal analysis may provide important insights into the relationship between participation and L2 learning. Instead of unilinear development of a single learner identity, we may find different participation patterns linked to distinct language learning affordances over time.
Foreign Language Pedagogical Knowledge: Toward a Developmental Theory of Beginning Teacher Practices
Authors: WATZKE JOHN L.
Published: February 2007

This longitudinal study focuses on how pedagogical content knowledge is initially represented and changes during the beginning teaching experiences of 9 teachers of French, German, and Spanish. The data consist of reflective journal entries, classroom observations, and focus group interviews collected during the first 2 years of foreign language (FL) teaching at the high school level. Techniques of grounded theory analysis were used to develop a theoretical framework comprehensive to the data. Four core categories—prior knowledge that frames instructional decisions, attitudes toward teacher control in the classroom, instructional goals for daily lessons, and considerations for responding to student affect—were identified to explain overarching change in foreign language pedagogical content knowledge. The results support the proposition that approaches to instruction, such as communicative language teaching, and their related theoretical underpinnings in language learning, develop as pedagogical content knowledge through a process of teaching, conflict, reflection, and resolution specific to the in‐service classroom context. Similar to research findings in other subject disciplines, the instructional practices of beginning FL teachers may initially be considered traditional, outdated, or even antithetical to their preservice preparation as control over students and the instructional content serve as a proxy for perceptions of successful teaching. Professional development of beginning teachers must support the ongoing transformation of pedagogical content knowledge in order to ensure that these early characteristics do not become lasting traits in long‐term teaching careers.
Radical Awareness and Word Acquisition Among Nonnative Learners of Chinese
Authors: SHEN HELEN H. , KE CHUANREN
Published: February 2007

This study investigates developmental trends in acquiring knowledge of radicals, radical perception skills, and skills in applying knowledge of radicals among nonnative learners of Chinese across learning levels. It also examines the relationship between the acquisition of radical knowledge and the development of radical perception and radical knowledge application skills, as well as how the development of radical knowledge application skills is associated with Chinese word acquisition. The results of this study suggest that radical knowledge, radical perception skills, and radical knowledge application skills do not develop synchronously across learning levels, but rather that each of them shows a unique developmental trend. A linear trend exists between the development of radical knowledge and the application of this knowledge; a moderate positive association is observed between the development of radical knowledge application skills and Chinese word acquisition. The pedagogical implications of these findings are suggested.
A Novel Mesh Electrode Catheter for Mapping and Radiofrequency Delivery at the Left Atrium‐Pulmonary Vein Junction: A Single‐Catheter Approach to Pulmonary Vein Antrum Isolation
Authors: ARRUDA MAURICIO S. , HE DING SHENG , FRIEDMAN PAUL , NAKAGAWA HIROSHI , BRUCE CHARLES , AZEGAMI KOJI , ANDERS ROBERT , KOZEL PETER , CHIAVETTA AMEDEO , MARAD PAUL , MACADAM DAVID , JACKMAN WARREN , WILBER DAVID J.
Published: February 2007

Background: Electrical isolation of pulmonary veins (PV) by radiofrequency (RF) ablation is often performed in patients with atrial fibrillation (AF). Current catheter technology usually requires the use of a multielectrode catheter for mapping in addition to the ablation catheter.

Purpose: We evaluated the feasibility and safety of using a single, expandable electrode catheter (MESH) to map and to electrically isolate the PV.

Methods and Results: Nineteen closed‐chest mongrel dogs, weighing 23–35 kg, were studied under general anesthesia. Intracardiac echocardiography (ICE) was used to guide transseptal puncture and to assess PV dimensions and contact of the MESH with PV ostia. ICE and angiography of RSPV were obtained before and after ablation, and prior to sacrifice at 7–99 days. An 11.5 Fr steerable MESH was advanced and deployed at the ostium of the RSPV. Recordings were obtained via the 36 electrodes comprising the MESH. For circumferential ablation, RF current was delivered at a target temperature of 62–65°C (4 thermocouples) and maximum power of 70–100 W for 180 to 300 seconds. Each animal received 1–4 RF applications. Entrance conduction block was obtained in 13/19 treated RSPVs. Pathological examination confirmed circumferential and transmural lesions in 13 of 19 RSPV. LA mural thrombus was present in 3 animals. There was no significant PV stenosis.

Conclusion: Based on this canine model, a new expandable MESH catheter may safely be used for mapping and for PV antrum isolation. This approach may decrease procedure time without compromising success rate in patients undergoing AF ablation.
Aortic Valve Sclerosis: Is It a Cardiovascular Risk Factor or a Cardiac Disease Marker?
Authors: Palmiero Pasquale , Maiello Maria , Passantino Andrea , Wasson Sanjeev , Reddy Hanumanth K.
Published: February 2007

Background: Aortic valve sclerosis, without stenosis, has been associated with an increased cardiovascular mortality and morbidity due to myocardial infarction. However, it is unclear whether it is a cardiovascular risk factor or a cardiac disease marker. The goal of our study is to evaluate the difference in the prevalence of cardiovascular disease and risk factors among patients with or without aortic sclerosis. Methods: This observational study compared a group of 142 consecutive subjects with aortic valve sclerosis, assigned as group S, with a group of 101 subjects without aortic sclerosis, assigned as group C. Patients with bicuspid aortic valves and those with antegrade Doppler velocity across aortic valve leaflets exceeding 2.0 m/sec were excluded. Results: Mean ages of groups S and C were 71 ± 8, and 68.8 ± 6 years, respectively (P value = not significant). The prevalence of smoking, diabetes, hypercholesterolemia, hypertension, pulse pressure, left ventricular diastolic dysfunction, atrial fibrillation, and stroke was not significantly different between the two groups. However, there was a significantly higher prevalence of left ventricular hypertrophy (P = 0.05), ventricular arrhythmias (P = 0.02), myocardial infarction (P = 0.04), and systolic heart failure (P = 0.04) in aortic sclerosis group. Conclusions: Aortic sclerosis is associated with a higher prevalence of left ventricular hypertrophy, ventricular arrhythmias, myocardial infarction, and systolic heart failure, while the prevalence of cardiovascular risk factors is not different between aortic sclerosis patients and controls. Hence, aortic sclerosis represents a cardiac disease marker useful for early identification of high‐risk patients beyond cardiovascular risk factors rate.
Correlation of Tei Index Obtained from Tissue Doppler Echocardiography with Invasive Measurements of Left Ventricular Performance
Authors: Su Ho‐Ming , Lin Tsung‐Hsien , Voon Wen‐Chol , Lee Kun‐Tai , Chu Chih‐Sheng , Yen Hsueh‐Wei , Lai Wen‐Ter , Sheu Sheng‐Hsiung
Published: February 2007

Background: The aim of this study is to correlate Tei index obtained from tissue Doppler echocardiography (TDE‐Tei index) defined as the ratio of the sum of isovolumetric contraction time (ICT) and isovolumetric relaxation time (IRT) over the ejection time (ET) with invasive measurements of left ventricular (LV) performance. Methods: Thirty‐four patients who underwent an echocardiographic examination and cardiac catheterization were studied. Invasive measurements of peak +dp/dt, peak −dp/dt, and isovolumic relaxation constant of the left ventricle (tau) were obtained from a micromanometer‐tipped catheter. Results: After a multivariate analysis, TDE‐Tei index had a negative correlation with ejection fraction (EF) (β=−0.384, P = 0.046) and positive correlation with tau (β= 0.397, P = 0.040). ET had a negative correlation with heart rate (β=−0.446, P = 0.005) and positive correlation with EF (β= 0.379, P = 0.015). ICT + IRT had a positive correlation with tau (β= 0.512, P = 0.002). ICT/ET had a negative correlation with EF (β=−0.657, P < 0.001) and positive correlation with peak early transmitral filling wave velocity (β= 0.385, P = 0.001). IRT/ET had a positive correlation with tau (β= 0.402, P = 0.018). Conclusions: TDE‐Tei index exerts a correlation both with accepted indices of LV systolic and diastolic function acquired by cardiac catheterization. Hence, TDE‐Tei index is a simple and feasible indicator in assessing overall LV function.
Transthoracic Echocardiographic Diagnosis of Mobile Aortic Arch Atherothrombosis Associated with Stroke
Authors: Meltzer Sara M. , Rigby Michael J. , Meltzer Richard S.
Published: February 2007

Aortic arch atherosclerosis is associated with an increased risk of stroke or TIA. Up to now, transesophageal echocardiography has been the standard method for diagnosing protruding and/or mobile aortic arch atherosclerosis. We report a case where a mobile aortic arch atheroma was diagnosed using transthoracic echo in a patient with a recent stroke.
Incidental Detection of Inferior Vena Caval Dissection by Intraoperative High Frequency Vascular Duplex Ultrasonography
Authors: Puwanant Sarinya , Click Roger L. , Kalra Manju , Farley David R. , Chandrasekaran Krishnaswamy
Published: February 2007

Inferior vena caval (IVC) dissection has been rarely reported. This could be due to less susceptibility of the venous structure to dissect or under recognition of this entity. We first report a case of IVC dissection detected by high frequency surface ultrasonography following tumor thrombectomy of adrenal cortical carcinoma. This report described the value of intraoperative surface echocardiography and reviewed previous literatures with regard to IVC dissection.
Cardiac MRI is Complementary to Echocardiography in the Assessment of Cardiac Masses
Authors: Altbach Maria I. , Squire Scott W. , Kudithipudi Vijayasree , Castellano Lisa , Sorrell Vincent L.
Published: February 2007

Despite the fact that the incidence of cardiac tumors is low, the prompt evaluation and adequate intervention of these is highly important. Although most tumors of the heart are considered histologically benign, there are significant risks associated with these “benign” tumors. These are associated with significant morbidity and mortality due to obstruction of blood flow, alterations of conduction, propagation of arrhythmias, and thromboembolism, depending on their size, location, and nature. With the advent of noninvasive imaging modalities—traditionally echocardiography; but more recently using cross‐sectional imaging with cardiac computed tomography and magnetic resonance imaging—cardiac tumors can be optimally assessed providing a greater opportunity for curative treatments by cardiothoracic surgery.
Evaluating Cardiac Sources of Embolic Stroke with MRI
Authors: Rustemli Asu , Bhatti Tandeep K. , Wolff Steven D.
Published: February 2007

The evaluation of patients with stroke includes identifying its etiology in order to appropriately tailor therapy. Currently, the diagnostic work‐up includes imaging of the brain, the arteries of the head and neck, the aorta, and the heart. Traditional methods of imaging include magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA), duplex ultrasound, and transthoracic echocardiography (TTE) and/or transesophageal echocardiography (TEE). While echocardiography remains a cornerstone in the field of cardiac imaging, MRI is increasingly able to assess for the most common causes of cardioembolic stroke such as left atrial/left atrial appendage thrombus, left ventricular thrombus, aortic atheroma, cardiac masses and patent foramen ovale. This review will focus on the advantages and limitations of echocardiography and cardiac magnetic resonance (CMR) imaging in diagnosing patients suspected of having an embolic stroke and the role these modalities play in clinical practice today.
Dobutamine Stress Magnetic Resonance Imaging
Authors: Rerkpattanapipat Pairoj , Gregory Hundley W.
Published: February 2007

Measurements of left ventricular function with cardiovascular magnetic resonance (CMR) at rest and during intravenous dobutamine are useful for identifying myocardial ischemia, viability, and the risk of subsequent cardiovascular events. Without ionizing radiation, intravascular iodinated contrast administration, or acoustic window limitations, CMR has emerged as a useful adjunct to transthoracic echocardiography for assessing patients with or suspected of having coronary artery disease.
Structural Features of C–S–H(I) and Its Carbonation in Air—A Raman Spectroscopic Study. Part I: Fresh Phases
Authors: Garbev Krassimir , Stemmermann Peter , Black Leon , Breen Chris , Yarwood Jack , Gasharova Biliana
Published: February 2007

The Raman spectra of a series of mechanochemically prepared calcium silicate hydrate samples of type C–S–H(I) with C/S ratios ranging from 0.2 to 1.5 reveal changes in structure with changes in the C/S ratio. These support the model of Stade and Wieker based entirely on the tobermorite structure. The main characteristic feature of the spectra is the Si–O–Si bending vibration at about 670 cm−1. Comparisons with bending frequencies of some known crystalline phases composed of single silicate chains led to an estimation of the mean Si–O–Si angles in the C–S–H(I) phases to be ∼140°. Finite silicate chains (Q2) dominate the structures of the samples at C/S ratios 0.2–1.0, the spectra showing characteristic bands from 1010 to 1020 cm−1. When the samples are measured in air, the spectra exhibit carbonate bands arising from surface carbonation. The ν1[CO3] bands obscure the characteristic Raman scattering of silicate units near 1080 cm−1, which is clearly evident in the fresh samples analyzed in closed capillaries. At C/S>1.00, dimers (Q1) are the main building unit of the silicate anionic structure, with a characteristic band at 889 cm−1. At C/S ratios 1.33 and 1.50, portlandite (Ca(OH)2) is also observed.
Structural Features of C–S–H(I) and Its Carbonation in Air—A Raman Spectroscopic Study. Part II: Carbonated Phases
Authors: Black Leon , Breen Chris , Yarwood Jack , Garbev Krassimir , Stemmermann Peter , Gasharova Biliana
Published: February 2007

The effects of carbonation of mechanochemically prepared C–S–H samples under ambient conditions for upto 6 months have been investigated by Raman spectroscopy and X‐ray diffraction. The type and extent of carbonation are strongly dependent on the initial CaO/SiO2 (C/S) ratio of the samples. Amorphous calcium carbonate hydrate is formed within minutes upon exposure to air. It crystallizes, over time, to give primarily vaterite at C/S≥0.67 and aragonite at C/S≤0.50. Calcite was not observed as a primary carbonation product within the time frame investigated. Decalcification upon storage also initiates silicate polymerization. The dimeric silicate units seen in the calcium‐rich phases polymerize rapidly to yield Q2 silicate moieties. After 6 months, broad bands are seen in most spectra, ascribed to poorly ordered silica. C–S–H phases with C/S ratios of 0.75 and 0.67 are the most resistant to carbonation, and even after 6 months of storage, Q2 silicate units still dominate their structures. The ability of Raman spectroscopy to probe the short‐range order of poorly crystalline materials is ideal for investigations of C–S–H structure. Additionally, the technique's sensitivity toward the various calcium carbonate polymorphs illuminates the sequence of carbonation and decalcification processes during aging of C–S–H. Of particular importance is the identification of amorphous calcium carbonate as the first carbonation product. Additionally, the formation of aragonite as a carbonation product is related to the presence of SiO2 gel in the aged samples.
Fabricating 2.5D SiCf/SiC Composite Using Polycarbosilane/SiC/Al Mixture for Matrix Derivation
Authors: Zhu Yunzhou , Huang Zhengren , Dong Shaoming , Yuan Ming , Jiang Dongliang
Published: February 2007

2.5D SiCf/SiC composites were produced by a modified polymer infiltration and pyrolysis process. Fine Al and SiC powders were first infiltrated into large inter‐bundle pores. During pyrolytic decomposition of the polymer, the active Al filler reacts with small carbon‐bearing polymer fragments, and reactive nitrogen atmosphere to form new phases of carbide or nitride. The volume expansion compensates for polymer shrinkage to a certain degree. The microstructural evolution and mechanical performances were characterized. The result indicates that the addition of Al fillers has significant influence on the mechanical properties of the composites. For the composite with Al loading, a proportional‐limit stress of 380 MPa and a maximum stress of 441 MPa are achieved.
Fingerprint Reagents with Dual Action: Color and Fluorescence
Authors: Almog Joseph , Levinton‐Shamuilov Genyia , Cohen Yaron , Azoury Myriam
Published: February 2007

ABSTRACT: We define “dual fingerprint reagents” as chemical formulations that produce with latent fingerprints in one stage impressions that are both colored and fluorescent. Solutions containing ninhydrin and group IIb metal salts appear to be true dual reagents. Application of these formulations to latent fingerprints on paper is as efficient as the two‐step process beginning with ninhydrin and followed by treatment with metal salt. In the color mode, fingerprint detectability with the two ninhydrin–metal salt reagents (one with zinc chloride and the other with cadmium chloride) is comparable with that of ninhydrin itself, in spite of the difference in color. The sensitivity is significantly higher in the fluorescence mode. To view the latent impressions the exhibits are treated with ninhydrin–metal salt reagents and observed under white light illumination and under fluorescence conditions. Cooling to liquid nitrogen temperature enhances the fluorescence considerably. In the shorter wavelength domain, ninhydrin–metal salt reagents exhibit higher sensitivity than the recently reported dual reagent, genipin. The latter is advantageous, however, in the longer wavelength domain, on paper items with strong self‐fluorescence, such as brown wrapping paper or paper printed with fluorescent ink. Upon reduction of the ninhydrin concentration 10‐fold, ninhydrin–metal salt formulations become purely fluorogenic reagents; no color is noticed but the fluorescence is as intense as with concentrated solutions. Working at lower concentrations is an advantage from ecological and economical viewpoints.
Thermal Degradation Analysis of Amino Acids in Fingerprint Residue by Pyrolysis GC–MS to Develop New Latent Fingerprint Developing Reagents*
Authors: Richmond‐Aylor Amy , Bell Suzanne , Callery Patrick , Morris Keith
Published: February 2007

ABSTRACT: Conventional development of latent fingerprints is compromised when the prints are decomposed by extreme temperatures, such as those encountered when a weapon cartridge is fired, an improvised explosive device is detonated, and/or in arson cases. Understanding how these extreme temperatures alter the chemical and physical properties of latent fingerprint residue could aid in the discovery of a reagent that could effectively develop these decomposed fingerprints. To mimic scenarios where fingerprints may be exposed to high heat conditions, standards of the five most abundant amino acids in fingerprint residue as well as extracted fingerprint residue were pyrolized under controlled conditions. Compounds identified as pyrolytic decomposition products were 3,6‐dimethylpiperazine‐2,5‐dione (from alanine), maleimide, and 2,5‐furandione (from aspartic acid). The pyrograms and selected ion traces show these products to hold promise as indicators of decomposed fingerprint residues and, therefore, may serve as good candidate substrates for a developing reagent.
Maggot Development During Morgue Storage and Its Effect on Estimating the Post‐Mortem Interval*
Authors: Huntington Timothy E. , Higley Leon G. , Baxendale Frederick P.
Published: February 2007

ABSTRACT: When insect evidence is obtained during autopsy, forensic entomologists make decisions regarding the effects of low‐temperature (−1°C to 4°C) storage of the body and associated insects when estimating the post‐mortem interval (PMI). To determine the effects of storage in a morgue cooler on the temperature of maggot masses, temperatures inside and outside of body bags containing a human cadaver and porcine cadavers (seven replicates) were measured during storage. Temperatures remained significantly higher (p<0.05) inside of the body bags relative to the cooler, and remained at levels sufficient for maggot feeding and development. If the assumption that no insect development takes place during preautopsy refrigeration is made, potential error rates in PMI estimation of 8.6–12.8% occur. The potential for blow fly larvae to undergo significant development while being stored in the morgue is a possibility that forensic entomologists should consider during an investigation involving samples collected from autopsy. Case and experimental evidence also demonstrate that substantial tissue loss can occur from maggot feeding during morgue storage.
Assessment of Intra‐ and Intercostal Variation in Rib Histomorphometry: Its Impact on Evidentiary Examination*
Authors: Crowder Christian , Rosella Laura
Published: February 2007

ABSTRACT:Rib histological age estimation requires the evaluation of the middle third of the sixth rib. Human ribs have thin cortices and, when recovered, are often fragmented or absent, making it difficult to identify a specific midthoracic rib. This research explores the amount of microstructure variation in the middle third of the midthoracic ribs and determines whether the sixth rib age prediction equation can be applied to non‐sixth ribs with similar accuracy. The amount of variability must be evaluated in order to meet the criterion for evidentiary examination. The sample consists of 120 cortical bone cross‐sections from the middle third of ribs 3–8 removed from 20 cadavers. For each rib, osteon population densities (OPDs) and associated age estimates were calculated. The results demonstrate that non‐sixth ribs can provide similar OPD values compared with those of the sixth ribs; however, individual variation proved to be significantly associated with bias, suggesting that individual factors influence the magnitude and direction of bias in non‐sixth rib OPD values. This demonstrates the importance of evaluating multiple cross‐sections (both intra‐ and inter‐rib) to estimate age due to the normal remodeling variation within individuals.
Genetic Data of Four X‐Chromosomal STRs in a Population Sample of Santa Catarina, Brazil
Authors: Cainé Laura M. , Pontes Lurdes , Abrantes David , Lima Gabriela , Pinheiro Fátima
Published: February 2007

POPULATION: A total of 184 healthy unrelated individuals (70 females and 114 males), autochthonous from Santa Catarina, Brazil.
Allele Frequencies of 20 Y‐Chromosomal Short Tandem Repeat Loci in a Tribal Population of Deccan Plateau, India
Authors: Hima Bindu G. , Trivedi R. , Kashyap V. K.
Published: February 2007

POPULATION: Eighty male individuals from a nomadic tribal population belonging to Dravidian and Indo‐Caucasian ethnicities from Deccan Plateau, Andhra Pradesh, India (1), were analyzed in the present study.
A Detailed Mechanistic Fragmentation Analysis of Methamphetamine and Select Regioisomers by GC/MS
Authors: Sachs Sandra B. , Woo Francis
Published: February 2007

ABSTRACT:A novel ring‐substituted methamphetamine regioisomer,N,α,4‐trimethyl phenmethylamine, was synthesized in order to study the validity of proposed structures for various mass spectrometry (MS)‐derived peaks in a methamphetamine fragmentation pattern. While other research efforts have studied aspects of methamphetamine in detail, a full fragmentation study has not been reported previously. In addition to showing molecular structures represented by fragment peaks, mechanisms for selected processes are detailed. An empirically derived procedure to easily determine by simple spectral peak pattern recognition the geometry of dimethyl‐ or ethyl‐substituted immonium ions (RRC=N+RR) wherem/z=58 is outlined. These results are platform independent for electron ionization (EI) instruments, but have also proven to be helpful in explaining spectral peaks observed in spectra from ion trap systems. The spectrum for the synthesized methamphetamine regioisomer was accurately predicted using this methodology. While this approach is useful in some casework, the converse may be more useful: when an unexpected or unusual peak pattern arises in a spectrum, being able to analyze it to determine the structure of the molecule. This paper gives an analyst the means to begin such retro‐synthetic analyses.
Role of scratch‐induced cutaneous prostaglandin D2 production on atopic‐like scratching behaviour in mice
Authors: Takaoka Akiko , Arai Iwao , Sugimoto Masanori , Futaki Nobuko , Sakurai Takanobu , Honma Yusuke , Nakaike Shiro
Published: February 2007

Abstract:  NC/Nga mice are known to develop scratching dermatitis akin to atopic dermatitis, under conventional (Conv), but not under the specific‐pathogen‐free (SPF) condition. In this study, we examined the effects of mechanical‐scratching on the spontaneous scratching counts (sign of itching), in relation to the cutaneous prostaglandin D2 (PGD2) levels in NC/Nga or BALB/c mice. Mechanical‐scratching increased the cutaneous barrier damage and PGD2 levels in both strain mice under the SPF condition. By 4 weeks of cohabitation with the skin‐lesioned NC/Nga mice, both the increase in the spontaneous scratching and development of dermatitis score were higher in the Conv‐NC/Nga than in the Conv‐BALB/c mice. At this time‐point, the cutaneous PGD2 level induced by mechanical‐scratching was significantly lower in the Conv‐NC/Nga when compared with that in the SPF‐NC/Nga mice, and that in the Conv‐BALB/c was almost equal to that in the SPF‐BALB/c mice. With mechanical scratches, the cohabitation‐induced scratching was suppressed in the Conv‐BALB/c, but not in the Conv‐NC/Nga mice. These results suggest that the scratch‐induced cutaneous PGD2 inhibits scratching and the subsequent development of dermatitis in BALB/c, while the impaired scratch‐induced cutaneous PGD2 production in the NC/Nga mice resulted in no suppression of scratching, and aggravated the dermatitis.
Grape seed proanthocyanidins promote apoptosis in human epidermoid carcinoma A431 cells through alterations in Cdki‐Cdk‐cyclin cascade, and caspase‐3 activation via loss of mitochondrial membrane potential
Authors: Meeran Syed M. , Katiyar Santosh K.
Published: February 2007

Abstract:  Dietary grape seed proanthocyanidins (GSPs) prevent photocarcinogenesis in mice. Here, we report that in vitro treatment of human epidermoid carcinoma A431 cells with GSPs inhibited cellular proliferation (13–89%) and induced cell death (1–48%) in a dose (5–100 μg/ml)‐ and time (24, 48 and 72 h)‐dependent manner. GSP‐induced inhibition of cell proliferation was associated with an increase in G1‐phase arrest at 24 h, which was mediated through the inhibition of cyclin‐dependent kinases (Cdk) Cdk2, Cdk4, Cdk6 and cyclins D1, D2 and E and simultaneous increase in protein expression of cyclin‐dependent kinase inhibitors (Cdki), Cip1/p21 and Kip1/p27, and enhanced binding of Cdki‐Cdk. The treatment of A431 cells with GSPs (20–80 μg/ml) resulted in a dose‐dependent increase in apoptotic cell death (26–58%), which was associated with an increased protein expression of proapoptotic Bax, decreased expression of antiapoptotic Bcl‐2 and Bcl‐xl, loss of mitochondrial membrane potential, and cleavage of caspase‐9, caspase‐3 and PARP. Pretreatment with the pan‐caspase inhibitor (z‐VAD‐fmk) blocked the GSP‐induced apoptosis in A431 cells suggesting that GSP‐induced apoptosis is associated primarily with the caspase‐3‐dependent pathway. Together, our study suggests that GSPs possess chemotherapeutic potential against human epidermoid carcinoma cells in vitro, further in vivo mechanistic studies are required to verify the chemotherapeutic effect of GSPs in skin cancers.
Air‐exposed keratinocytes exhibited intracellular calcium oscillation
Authors: Denda Mitsuhiro , Denda Sumiko
Published: February 2007

We previously demonstrated that calcium propagation plays a crucial role in epidermal homeostasis when the epidermis was exposed to a dry environment. In the present study, we first demonstrated the intracellular calcium oscillation in cultured human skin keratinocytes. On partial exposure of cultured human keratinocytes to air, a transient increase of intracellular calcium concentration appeared, followed by a wave‐like increase in the unexposed keratinocytes, showing oscillations with a frequency that varied from cell to cell. There appeared to be no correlation between the oscillation frequencies in adjacent cells. The increase of calcium concentration did not appear when calcium was removed from the medium or when suramin, a purinergic receptor antagonist, was added. The ATP concentration also increased immediately after keratinocytes were exposed to air. We hypothesize that ATP is secreted from keratinocytes on exposure to air, and induces an increase of intracellular calcium concentration.