bluuebunny/crossref_metadata_2025 huggingface dataset:
Further observations on the usefulness of the sonographic Murphy sign in the evaluation of suspected acute cholecystitis
Authors: Bree Robert L.
Published: February 2007

A positive sonographic Murphy sign, the presence of maximal tenderness elicited over a sonographically localized gallbladder, has been reported to be a helpful adjunctive finding in patients with proven acute cholecystitis who are evaluated with ultrasonography. We evaluated 200 patients with right upper quadrant pain, thought to be acute cholecystitis. Results of ultrasound examinations and subsequent follow‐up were tabulated. The sensitivity of the sonographic Murphy sign in acute cholecystitis was 86% with a specificity of 35%, positive predictive value of 43%, and negative predictive value of 82%. The sensitivity of the sonographic findings, including stones, gallbladder wall edema, and pericholecystic fluid collections, was 93%, a specificity of 53%. The combination of the Murphy sign accompanied by gallstones yielded a specificity of 77%. The large number of false positives, and only moderate improvement in specificity when accompanied by gallstones, makes this sign unreliable in separating acute from chronic cholecystitis. © 1995 John Wiley & Sons, Inc.
Thyroid nodules: Re‐evaluation with ultrasound
Authors: Takashima Shodayu , Fukuda Haruki , Nomura Naoko , Kishimoto Haruyoshi , Kim Tonsok , Kobayashi Tetsuro
Published: February 2007

The purpose of this study was to clarify ultrasound (US) evaluation of microcalcifications and determine whether the calcifications seen in US scans can reliably predict malignant thyroid tumors. Diagnostic accuracy of microcalcification and other various signs seen in US scans for predicting malignancy was evaluated prospectively in 259 pathologically verified thyroid nodules. Sonographic and pathologic correlation of calcifications was performed on 69 of 99 surgically removed nodules.

Pathologic studies revealed that hyperechoic areas with acoustic shadowing represented mostly amorphous dense calcifications and sometimes microcalcifications, but small particles without acoustic shadowing mainly reflected microcalcifications and sometimes large amount of fibrous bands and condensed colloids. of the various sono‐graphic signs, microcalcification showed the highest accuracy (76%), specificity (93%), and positive predictive value (70%) for malignancy as a single sonographie sign, but its sensitivity (36%) was poor. Although sonographic microcalcification showed relatively high specificity, the accuracy of this finding for malignancy was insufficient. © 1995 John Wiley & Sons, Inc.
Image‐directed and color Doppler ultrasonography in the diagnosis of postbiopsy arteriovenous fistulas of native kidneys
Authors: Özbek S. Süreyya , Memiş Ahmet , Killi Refik , Karaca Erdal , Kabasakal Caner , Mir Sevgi
Published: February 2007

Using image‐directed and color Doppler ultrasonography (ICDUS), we examined 65 patients with single kidney biopsy and diagnosed one arteriovenous fistula (AVF) in each of 8 kidneys. Three of them were associated with pseudoaneurysms. Three of the patients with AVF who presented with macrohematuria underwent angiography. Therapeutic percutaneous embolization was performed in 2 of them. The remaining 6 patients were followed up with ICDUS. All the lesions had disappeared at the end of a 6‐month period. We conclude that ICDUS is an easy and noninvasive imaging technique in the diagnosis of postbiopsy native renal AVFs. © 1995 John Wiley & Sons, Inc.
Evaluation of twin growth status at birth using individualized growth assessment: Comparison with conventional methods
Authors: Xu Bishong , Deter Russell L. , Milner Lizabeth L. , Hill Reba M.
Published: February 2007

Objective: We sought to evaluate the growth status of twins at birth using individualized growth assessment methods and to compare this assessment with that obtained with conventional methods.

Study design: Twenty twin pregnancies were studied longitudinally with ultrasound. Measurements of the head and abdominal cubes (A, B), head circumference (HC), abdominal circumference (AC), thigh circumference (ThC), and femur diaphysis length (FDL) made in the 2nd trimester were used to specify Rossavik growth models for each parameter in each fetus. These models were used to predict weight (WT), HC, AC, ThC, and crown–head length (CHL) at birth. Actual birth measurements made within 24 hours of delivery were compared to predicted values, the latter corrected using singleton [corrects for both technical problems (TP)] or twin [corrects for both technical problems (TP) and decreased soft‐tissue deposition (DSTD)] correction factors where appropriate. Two sets of growth potential realization index (GPRI) values and their corresponding neonatal growth assessment scores (NGAS) were calculated and compared to previously established normal values. Birth measurements were compared with appropriate population age‐specific size curves. These data were used to characterize and classify the growth status of each twin neonate.

Results: Individualized growth assessment identified five primary types of growth outcomes: normal (Group I, 45%); primarily DSTD (Group II, 22.5%); IUGR (Group III, 15%); above average soft‐tissue deposition (Group IV, 5%); and growth acceleration (Group V, 7.5%). Within Group I was a subgroup with evidence of DSTD (Group Ib, 33.3% of Group I). Group II could be divided into two subgroups, one with only DSTD (Group IIa, 44.4% of Group II) and one with both DSTD and other growth abnormalities (Group IIb, 55.6% of Group II). Group III had multiple growth abnormalities which were more severe than those seen in Group II. All normal neonates were AGA and had virtually all anatomic parameters within their respective normal ranges. Of the neonates with definite evidence of IUGR (Groups IIb and III), only 4 of 11 (36.4%) were SGA and only 6 of 11 (54.5%) had any of the five anatomic parameters below their respective normal ranges. Only 1 of 3 (33.3%) of neonates with growth acceleration was LGA and none (0%) of the five anatomic parameters were above their respective normal ranges.

Conclusions: Individualized growth assessment methods provide a more comprehensive assessment of growth outcome in twins and detect a decrease in soft‐tissue deposition not identifiable with conventional growth assessment procedures. The latter procedures are also less sensitive in the detection of both IUGR and growth acceleration. © 1995 John Wiley & Sons, Inc.
Causes of increasing width of right anterior extrarenal space seen in ultrasonographic examinations
Authors: Chen Jyh‐Jou , Changchien Chi‐Sin , Kuo Chung‐Huang
Published: February 2007

The right anterior extrarenal space is composed of the perirenal fascia, the right anterior perirenal space, the right anterior pararenal space, and the liver capsule. To clarify the probable causes of an increasing width of the right anterior extrarenal space, the width was measured using ultrasonography for a period of 8 months. The right anterior extrarenal space was measured 3 cm from the superior renal pole and the smallest width obtained in several different scan planes was used. In 1,114 ultrasound examinations, 35 patients were found to have an increased width of the right anterior extrarenal space. Among the 35 cases, the common probable causes for such a condition were found in 27 cases. Eight patients had hyperechogenicity in the right pararenal space, a condition considered to be due to an acute inflammation, including acute pancreatitis, acute cecal diverticulitis, acute appendicitis, ischemic bowel, acute cholangitis, liver abscess, and penetrated duodenal ulcer. Chronic inflammations of an adjacent organ, a previous history of laparotomy, a malignancy with peritoneal metastases, and treatment with corticosteroid were considered the causes behind the condition in the 19 patients with normal echogenicity. For the remaining 8 patients, causes were not found during the follow‐up period. This study indicates that life‐threatening diseases, such as acute or chronic inflammatory diseases and malignancy of the abdomen, could be the cause of an increase in the width of this space. © 1995 John Wiley & Sons, Inc.
Relationship between portal blood flow measured by image‐directed doppler ultrasonography and hepatic blood flow measured by indocyanine green constant infusion in patients with cirrhosis
Authors: Bolognesi Massimo , Sacerdoti David , Merkel Carlo , Gatta Angelo
Published: February 2007

The validity of portal blood flow measurement in image‐directed Doppler ultrasound (PBF‐IDU) is still under debate.

In this study PBF‐IDU has been compared with hepatic blood flow measured by the indocyanine green constant infusion technique (HBF‐ICG), which is the reference invasive method with which to measure total hepatic blood flow in man (ie, the sum of hepatic artery and portal vein blood flow).

In 27 cirrhotic patients with hepatopetal portal blood flow, PBF‐IDU was measured by multiplying the portal vein cross‐sectional area by the averaged mean velocity of blood in the vessel. About 1 hour later HBF‐ICG was measured during hepatic vein catheterization performed to evaluate portal hypertension. In 19 of 27 patients, intra‐hepatic arterial resistance indices were also measured.

PBF‐IDU and HBF‐ICG were 1.010 ± 0.555 L/min (M ± SD) and 1.496 ± 0.731 L/min, respectively. Blood flow measured by the two methods showed a close correlation (r = 0.80, p < 0.001). The regression line showed that HBF‐ICG was systematically higher than PBF‐IDU (mean difference + 29 ± 30%). The hepatic artery component of HBF‐ICG probably accounted for the difference. An inverse correlation was found between the differences between the two procedures and intrahepatic arterial resistance indices (r = −0.52, p = 0.04), which may be considered indirect parameters of arterial supply. It can be concluded that image‐directed Doppler ultrasound is a sufficiently accurate method to measure portal blood flow in cirrhotics. © 1995 John Wiley & Sons, Inc.
Sonohysterography of the uterine cavity: Preliminary investigations
Authors: Gaucherand Pascal , Piacenza Jean M. , Salle Bruno , Rudigoz René Ch.
Published: February 2007

Objective: To compare sonohysterography (SH), in the exploration of the uterine cavity, with classical transvaginal sonography (TVS), hysterography (HSG), and hysteroscopy.

Study design: 104 consecutive patients evaluated for uterine disorders underwent both TVS and SH. SH was obtained by distension of the uterine cavity with the instillation of an isotonic saline solution; 36 patients also underwent HSG; 82 women underwent surgery. Histologic findings were considered as gold standard. The criteria used to compare these methods were sensitivity, specificity, and negative and positive predictive values (NPV, PPV) for identifying pathology.

Results: 3 instillation failures occurred. SH was found to be more effective (sensitivity 94%, specificity 98%) than HSG (sensitivity 67%, specificity 94%). The difference between TVS and SH was less marked, SH showing some superiority (sensitivity 88%, specificity 98%) to TVS (sensitivity 77%, specificity 93%).

Conclusion: SH represents an improvement over conventional TVS and is fully capable of replacing HSG for the study of the uterine cavity. © 1995 John Wiley & Sons, Inc.
Visceral slide for intraperitoneal adhesions? A prospective study in 48 patients with surgical correlation
Authors: Uberoi R. , D'Costa H. , Brown C. , Dubbins P.
Published: February 2007

Bowel perforation in patients undergoing laparoscopic surgery is an uncommon but serious complication. Bowel adherent to the anterior abdominal wall due to adhesions is considered a particular risk. It has been suggested that transabdominal ultrasound can reliably predict the presence of intraperitoneal adhesions. Normal bowel excursions (visceral slide) in 15 volunteers with no history of surgery or peritonitis and in 48 patients undergoing abdominal surgery were evaluated. Visceral slide during spontaneous respiration (SRSL) with manual compression (MCSL) and exaggerated respiration (ESL) was assessed in all 4 quadrants. Adhesions were found in 43 quadrants (12 in the RUQ, 6 in the LUQ, 14 in the RIF, and 11 in the LIF) in 21 patients at surgery. Reduced SRSL detected fibrous adhesions in 6 of 15 quadrants, but only 3 of 28 fibrinous adhesions, with an overall sensitivity of 21%, specificity of 94%, and accuracy of 76%. MCSL detected 9 of 15 fibrous and 9 of 28 fibrinous adhesions, with an overall sensitivity of 42%, specificity of 73.5%, and accuracy of 62%. ESL detected 6 of 15 fibrous and 3 of 28 fibrinous adhesions, with an overall sensitivity of 20%, specificity of 76%, and accuracy of 63%. Preliminary results suggest that ultrasound can detect adhesions preoperatively, but the overall sensitivity is poor and the number of false‐positives and false‐negatives make it unreliable for routine use. © 1995 John Wiley & Sons, Inc.
Hepatic venous Doppler waveforms: Changes in pregnancy
Authors: Roobottom C. A. , Hunter J. D. , Weston M. J. , Dubbins P. A.
Published: February 2007

A total of 75 fasted healthy normal volunteers were examined during various stages of pregnancy. Examinations were performed in a supine position using an Acuson 128 ultrasound scanner with a 3.5 MHz transducer. Doppler interrogation of the middle hepatic vein was made during quiet respiration by one of three examiners. The Doppler waveforms were subsequently assessed blindly by one of the authors and categorized as normal, damped, or flat. Between 12 and 20 weeks, the majority of patients had normal hepatic pulsatility (64%) with 20% damped and 16% flat. Between 20 and 30 weeks there was a significant change (p > 0.001) with 68% being flat, 20% damped, and only 12% normal. In the last 10 weeks of pregnancy the changes were more marked: 80% were flat, 12% dampened, and 8% normal. There was a profound change in hepatic venous pulsatility during pregnancy. Hepatic waveforms changed from their normal pulsatile nature to become completely flat with increasing gestation. These changes were more frequent and more marked the further gestation progressed. © 1995 John Wiley & Sons, Inc.
Early fetal circulation in pregnancies complicated by retroplacental hematoma
Authors: Rizzo Giuseppe , Capponi Alessandra , Soregaroli Mirella , Arduini Domenico , Romanini Carlo
Published: February 2007

The objective of this study was to investigate the effects in early gestation of retroplacental hematomas on Doppler indices measured in different fetal vascular districts and to relate these changes, if any, to the volume of hematoma and pregnancy outcome. Thirty‐eight pregnancies complicated by bleeding and ultrasonographic findings of retroplacental hematomas were considered for this study. Menstrual age ranged between 9 and 14 weeks. Blood flow velocity waveforms were measured in the umbilical artery, descending aorta, middle cerebral artery, and inferior vena cava. The pulsatility index in arterial vessels was calculated as well as the percentage reverse flow in the inferior vena cava. The values obtained were compared to previously constructed reference limits. No significant differences were found for any of the Doppler indices when the values obtained in pregnancies complicated by retroplacental hematomas were compared to the reference limits. Furthermore no significant relationships were found between the Doppler indices and either the size of hematoma or pregnancy outcome. In conclusion, retroplacental hematoma does not induce hemodynamic effects in the fetal circulation before 14 weeks, menstrual age. These data do not support the use of Doppler ultrasonography in early gestation for pregnancies complicated by bleeding and retroplacental hematomas. © 1995 John Wiley & Sons, Inc.
Quantitative characterization of color Doppler images: Reproducibility, accuracy, and limitations
Authors: Delorme Stefan , Weisser Gerald , Zuna Ivan , Fein Martin , Lorenz Adolf , van Kaick Gerhard
Published: February 2007

A computer‐based quantitative analysis for color Doppler images of complex vascular formations is presented. The red‐green‐blue‐signal from an Acuson XP10 is frame‐grabbed and digitized. By matching each image pixel with the color bar, color pixels are identified and assigned to the corresponding flow velocity (color value). Data analysis consists of delineation of a region of interest and calculation of the relative number of color pixels in this region (color pixel density) as well as the mean color value. The mean color value was compared to flow velocities in a flow phantom. The thyroid and carotid artery in a volunteer were repeatedly examined by a single examiner to assess intra‐observer variability. The thyroids in five healthy controls were examined by three experienced physicians to assess the extent of inter‐observer variability and observer bias. The correlation between the mean color value and flow velocity ranged from 0.94 to 0.96 for a range of velocities determined by pulse repetition frequency. The average deviation of the mean color value from the flow velocity was 22% to 41%, depending on the selected pulse repetition frequency (range of deviations, −46% to +66%). Flow velocity was underestimated with inadequately low pulse repetition frequency, or inadequately high reject threshold. An overestimation occurred with inadequately high pulse repetition frequency. The highest intra‐observer variability was 22% (relative standard deviation) for the color pixel density, and 9.1% for the mean color value. The inter‐observer variation was approximately 30% for the color pixel density, and 20% for the mean color value. In conclusion, computer assisted image analysis permits an objective description of color Doppler images. However, the user must be aware that image acquisition under in vivo conditions as well as physical and instrumental factors may considerably influence the results. © 1995 John Wiley & Sons, Inc.
Assessment of fetal breathing movements using three different ultrasound modalities
Authors: Bruner Joseph P. , Coggins Teresa
Published: February 2007

Twenty‐five consecutive women in the third trimester of pregnancy were studied to determine the presence or absence of fetal breathing movements using three different ultrasound imaging techniques. Using real‐time B‐mode observation of the fetal trunk as the standard, image‐directed pulsed wave Doppler insonation of the umbilical vein confirmed the presence of breathing movements with a sensitivity of 100% and the absence of breathing movements with a specificity of 100%. The sensitivity and specificity of color Doppler imaging of the fetal naso‐and oropharynx for the presence or absence of fetal breathing movements were 96% and 100%, respectively. In the current study, the detection of fetal breathing movements by three different ultrasound modalities was virtually interchangeable. © 1995 John Wiley & Sons, Inc.
Ionization of anabolic steroids by adduct formation in liquid chromatography electrospray mass spectrometry
Authors: Pozo Oscar J. , Van Eenoo Peter , Deventer Koen , Delbeke Frans T.
Published: February 2007

The ionization of 46 anabolic steroids has been studied. The absence of basic or acidic moieties in most of these analytes makes their direct ionization as [M + H]+ by atmospheric pressure interfaces difficult. The formation of adducts with different components of the mobile phase has been found to be an efficient way to ionize anabolic steroids by electrospray. Different mobile phases using methanol (MeOH) or acetonitrile as organic solvent and HCOOH, Na+ or NH4+ as additives have been tested to favor the adduct formation. A direct correlation between the chemical structure of the anabolic steroid and the possibility to ionize it in a particular chromatographic condition has been found. According to their ionization, anabolic steroids can be divided into seven different groups depending on both the nature and the relative position of their functional groups. The formation of different adducts such as [M + Na + MeOH]+ or [M + H + CH3 CN − H2O]+ is required in order to ionize some of these groups and the optimal mobile phase composition for each group of anabolic steroids is proposed. Despite the ionization limitations due to their chemical structure, most of tested anabolic steroids could be ionized using the adduct formation approach. Copyright © 2007 John Wiley & Sons, Ltd.
Holocene colluvial (debris‐flow and water‐flow) processes in eastern Norway: stratigraphy, chronology and palaeoenvironmental implications
Authors: Sletten K. , Blikra L. H.
Published: February 2007

Very little is known about the temporal pattern and the palaeoenvironmental implications of Holocene colluvial processes (debris‐flow and water‐flow processes) in eastern Norway. In this study, well‐dated sedimentary successions from 19 deep excavations are used to reconstruct Holocene colluvial activity in upper Gudbrandsdalen, eastern Norway. Following deglaciation, debris‐flow and water‐flow events have been common in upper Gudbrandsdalen throughout the Holocene, with 62% of the recognised debris‐flow and water‐flow units deposited prior to 5000 cal. yr BP. Relatively high colluvial activity is recorded at ca. 8600–7400, 2400–1900 and 800–400 cal. yr BP, with a conspicuous peak at ca. 8500–8100. Periods of relatively low colluvial activity are recorded at ca. 7100–6500, 5900–5300 and 3500–2500 cal. yr BP. Two different weather situations, unusually heavy rains and warm periods during the snowmelt season, are responsible for triggering colluvial processes in this area. These different weather situations may in turn be related to different climatic conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Robust Nash Equilibrium in multi‐model LQ differential games: analysis and extraproximal numerical procedure
Authors: Jiménez‐Lizárraga Manuel , Poznyak Alex
Published: February 2007

This paper tackles the problem of finding a Nash equilibrium for a multi‐model differential game. Player's dynamics is governed by an ordinary differential equation with unknown parameters (Multi‐Model Representation) from a given finite set. The problem consists in the designing of min–max strategies for each player which guarantee an equilibrium for the worst‐case scenario. Based on the Robust Maximum Principle necessary conditions for a game to be in Robust Nash Equilibrium are derived. The LQ differential games are considered in detail. It is shown that the initial min–max differential game may be converted into a standard static game given in a multi‐dimensional simplex. A numerical procedure for resolving the LQ differential game is designed. Copyright © 2007 John Wiley & Sons, Ltd.
Conjugated polymers with tethered electron‐accepting moieties as ambipolar materials for photovoltaics
Authors: Cravino Antonio
Published: February 2007

Conjugated polymers are of increasing interest as semiconductors for soft (opto)electronic devices, including photovoltaic elements. A promising conversion of solar energy into electrical energy is possible with blends of soluble electron donor‐type conjugated polymers and fullerenes as electron‐acceptor, transporting component. This approach, called bulk‐heterojunction, suggested the preparation of intrinsic ambipolar materials to control simultaneously the electronic and morphological properties. On these bases, the covalent grafting of acceptor moieties onto conjugated backbones seemed attractive for the preparation of intrinsically ambipolar polymeric materials (‘double‐cable’ polymers) as an alternative to donor–acceptor composites. The design, characterisation and application of this novel class of polymers are reviewed taking into account the current understanding of organic photovoltaics. Copyright © 2007 Society of Chemical Industry
Monodisperse magnetic nanoparticles for biomedical applications
Authors: Xu Chenjie , Sun Shouheng
Published: February 2007

Magnetic nanoparticles that are superparamagnetic with high saturation moment have great potential for biomedical applications. Solution‐phase syntheses have recently been applied to make various kinds of monodisperse magnetic nanoparticles with standard deviation in diameter of less than 10%. However, the surface of these nanoparticles is coated with a layer of hydrocarbon molecules due to the use of lipid‐like carboxylic acid and amine in the syntheses. Surface functionalization leads to the formation of water‐soluble nanoparticles that can be further modified with various biomolecules. Such functionalization has brought about several series of monodisperse magnetic nanoparticle systems that have shown promising applications in protein or DNA separation, detection and magnetic resonance imaging contrast enhancement. The goal of this mini review is to summarize the recent progress in the synthesis and surface modification of monodisperse magnetic nanoparticles and their applications in biomedicine. Copyright © 2007 Society of Chemical Industry
III‐V concentrator solar cell reliability prediction based on quantitative LED reliability data
Authors: Vázquez Manuel , Algora Carlos , Rey‐Stolle Ignacio , González José Ramón
Published: February 2007

III‐V Multi Junction (MJ) solar cells based on Light Emitting Diode (LED) technology have been proposed and developed in recent years as a way of producing cost‐competitive photovoltaic electricity. As LEDs are similar to solar cells in terms of material, size and power, it is possible to take advantage of the huge technological experience accumulated in the former and apply it to the latter. This paper analyses the most important parameters that affect the operational lifetime of the device (crystalline quality, temperature, current density, humidity and photodegradation), taking into account experience on the reliability of LEDs. Most of these parameters are less stressed for a III‐V MJ solar cell working at 1000 suns than for a high‐power LED. From this analysis, some recommendations are extracted for improving the long‐term reliability of the solar cells. Compared to high‐power LEDs based on compound semiconductors, it is possible to achieve operational lifetimes higher than 105 hours (34 years of real‐time operation) for III‐V high‐concentration solar cells. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and photovoltaic properties of a low‐band‐gap polymer consisting of alternating thiophene and benzothiadiazole derivatives for bulk‐heterojunction and dye‐sensitized solar cells
Authors: Shin Won Suk , Kim Sung Chul , Lee Seung‐Joon , Jeon Han‐Su , Kim Mi‐Kyoung , Naidu B. Vijaya Kumar , Jin Sung‐Ho , Lee Jin‐Kook , Lee Jae Wook , Gal Yeong‐Soon
Published: February 2007

We synthesized a novel low‐band‐gap, conjugated polymer, poly[4,7‐bis(3′,3′‐diheptyl‐3,4‐propylenedioxythienyl)‐2,1,3‐benzothiadiazole] [poly(heptyl4‐PTBT)], consisting of alternating electron‐rich, diheptyl‐substituted propylene dioxythiophene and electron‐deficient 2,1,3‐benzothiadiazole units, and its photovoltaic properties were investigated. A thin film of poly(heptyl4‐PTBT) exhibited an optical band gap of 1.55 eV. A bulk‐heterojunction solar cell with indium tin oxide/poly(3,4‐ethylenedioxythiophene)/poly(heptyl4‐PTBT): methanofullerene [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) (1:4)/LiF/Al was fabricated with poly(heptyl4‐PTBT) as an electron donor and PCBM as an electron acceptor and showed an open‐circuit voltage, short‐circuit current density, and power conversion efficiency of 0.37 V, 3.15 mA/cm2, and 0.35% under air mass 1.5 (AM1.5G) illumination (100 mW/cm2), respectively. A solid‐state, dye‐sensitized solar cell with a SnO2:F/TiO2/N3 dye/poly(heptyl4‐PTBT)/Pt device was fabricated with poly(heptyl4‐PTBT) as a hole‐transport material. This device exhibited a high power conversion efficiency of 3.1%, which is the highest power conversion efficiency value with hole‐transport materials in dye‐sensitized solar cells to date. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1394–1402, 2007
Fragmentation study of iridoid glucosides through positive and negative electrospray ionization, collision‐induced dissociation and tandem mass spectrometry
Authors: Es‐Safi Nour‐Eddine , Kerhoas Lucien , Ducrot Paul‐Henri
Published: February 2007

Mass spectrometric methodology based on the combined use of positive and negative electrospray ionization, collision‐induced dissociation (CID) and tandem mass spectrometry (MS/MS) has been applied to the mass spectral study of a series of six naturally occurring iridoids through in‐source fragmentation of the protonated [M+H]+, deprotonated [MH]− and sodiated [M+Na]+ ions. This led to the unambiguous determination of the molecular masses of the studied compounds and allowed CID spectra of the molecular ions to be obtained. Valuable structural information regarding the nature of both the glycoside and the aglycone moiety was thus obtained. Glycosidic cleavage and ring cleavages of both aglycone and sugar moieties were the major fragmentation pathways observed during CID, where the losses of small molecules, the cinnamoyl and the cinnamate parts were also observed. The formation of the ionized aglycones, sugars and their product ions was thus obtained giving information on their basic skeleton. The protonated, i.e. [M+H]+ and deprotonated [MH]−, ions were found to fragment mainly by glycosidic cleavages. MS/MS spectra of the [M+Na]+ ions gave complementary information for the structural characterization of the studied compounds. Unlike the dissociation of protonated molecular ions, that of sodiated molecules also provided sodiated sugar fragments where the C fragment corresponding to the glucose ion was obtained as base peak for all the studied compounds. Copyright © 2007 John Wiley & Sons, Ltd.
Online aerosol mass spectrometry of single micrometer‐sized particles containing poly(ethylene glycol)
Authors: Bogan Michael J. , Patton Elizabeth , Srivastava Abneesh , Martin Sue , Fergenson David P. , Steele Paul T. , Tobias Herbert J. , Gard Eric E. , Frank Matthias
Published: February 2007

The analysis of poly(ethylene glycol) (PEG)‐containing particles by online single particle aerosol mass spectrometers equipped with laser desorption/ionization (LDI) is reported. We demonstrate that PEG‐containing particles are useful in the development of aerosol mass spectrometers because of their ease of preparation, low cost, and inherently recognizable mass spectra. Solutions containing millimolar quantities of PEGs were nebulized and, after drying, the resultant micrometer‐sized PEG‐containing particles were sampled. LDI (266 nm) of particles containing NaCl and PEG molecules of average molecular weight <500 Da generated mass spectra reminiscent of mass spectra of PEG collected by other mass spectrometer platforms including the characteristic distribution of positive ions (Na+ adducts) separated by the 44 m/z units of the ethylene oxide units separating each degree of polymerization. PEGs of average molecular weight >500 Da were detected from particles that also contained the tripeptide tyrosine‐tyrosine‐tyrosine or 2,5‐dihydroxybenzoic acid, which were added to nebulized solutions to act as matrices to assist LDI using pulsed 266 nm and 355 nm lasers, respectively. Experiments were performed on two aerosol mass spectrometers, one reflectron and one linear, that each utilize two time‐of‐flight mass analyzers to detect positive and negative ions created from a single particle. PEG‐containing particles are currently being employed in the optimization of our bioaerosol mass spectrometers for the application of measurements of complex biological samples, including human effluents, and we recommend that the same strategies will be of great utility to the development of any online aerosol LDI mass spectrometer platform. Copyright © 2007 John Wiley & Sons, Ltd.
High‐pressure Scanning Tunneling Microscopy: Tip Reactions
Authors: Weeks Brandon L. , Zhang Gengxin
Published: February 2007

Scanning tunneling microscopy (STM) is an ideal tool to image conducting and semiconducting surfaces with atomic resolution. The technique provides high‐resolution images in vacuum or even high‐pressure environments. Since STM can be operated at elevated pressures and temperatures, images can be collected in situ under catalytic conditions. In this work, we demonstrate that artifacts can be observed when imaging in situ since reactions can occur on the tip, and care should be taken when analyzing the data obtained. SCANNING 29: 5–10, 2007. Copyright © 2007 Wiley Periodicals, Inc.
Variation in demographic and fine‐scale genetic structure with population‐history stage of Hemerocallis taeanensis (Liliaceae) across the landscape
Authors: Chung Mi Yoon
Published: February 2007

Fine‐scale genetic structure (FSGS) in plant populations is expected to be influenced by variation in demographic processes across space and over time. I chose Hemerocallis taeanensis (Liliaceae), a perennial herb with a rapid population turnover, to quantify how demographic structure and FSGS change with a population's history (i.e., density). Nonaccumulative O‐ring statistic and spatial autocorrelation analysis (kinship coefficient, Fij) were used to quantify spatial patterns of individuals and FSGS in four populations belonging to two population stages (expansion and maturation) in west‐central Korea. The O‐ring function revealed that significant aggregation of individuals occurs at short spatial scales during the earlier stage of population expansion, which reflects restricted seed dispersal around maternal individuals. However, this pattern disappears as the population density increases during population maturation, probably due to a high population density. Significant evidence of FSGS was found in two populations at the stage of population expansion (Sp, a statistic which describes the rate of decrease of pairwise kinship with distance, was 0.018 and 0.029). The results show that most seeds fall around maternal plants when initially established colonists proliferate at suitable microhabitats. In contrast to this, much lower Sp values (−0.003 and 0.004) were estimated for two populations at the stage of population maturation, which may result from the overlapping of seed shadows due to high adult density. All of these results demonstrate considerable variation in within‐population demographic and genetic structures of H. taeanensis with respect to population temporal stage across the landscape.
Fatty Acids in Vernonia Produced in the Mid‐Atlantic Region of the United States
Authors: Bhardwaj H. L. , Hamama A. A. , Dierig D. A.
Published: February 2007

Vernonia galamensis [(Cass.) Less.] is a native of Ethiopia and Eritrea. Seed of vernonia contain substantial quantities of naturally epoxidized oil, which is used in the paint industry to reduce emissions of volatile organic compounds that produce smog resulting from the use of petroleum‐based (alkyd‐resin) paint. Epoxidized oil is also used in the manufacture of plasticizers, additives to polyvinyl chloride, polymer blends and coatings, and cosmetic and pharmaceutical applications. Previous research has indicated that vernonia has potential for commercialization in the mid‐Atlantic region of the United States. This study characterized fatty acids in oil from vernonia grown in this latter region. Vernonia oil, from 14 vernonia lines grown during 1995 and 1996 under field conditions in Virginia, contained 3.3, 3.0, 5.0, 15.0, 0.2, 0.5, 0.4, and 72.7%, respectively, of C16:0, C18:0, C18:1, C18:2, C18:3, C20:0, C20:1, and vernolic (C18:1 epoxy) fatty acids. Effects of genotypes on vernonia oil quality were generally not significant whereas the effects of years were significant. The concentration of vernolic acid was positively correlated with oil concentration but negatively correlated with concentrations of all individual fatty acids, except for C18:3.
Prevalence of infection and 18S rRNA gene sequences ofCytauxzoonspecies in Iberian lynx (Lynx pardinus) in Spain
Authors: MILLÁN J. , NARANJO V. , RODRÍGUEZ A. , DE LA LASTRA J. M. PÉREZ , MANGOLD A. J. , DE LA FUENTE J.
Published: February 2007

The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Only about 160 individuals remain in 2 separate metapopulations in Southern Spain (Sierra Morena and Doñana). We obtained blood samples of 20 lynxes captured from 2004 to 2006, and determined the prevalence of infection and genetic diversity ofCytauxzoonspp. using 18S rRNA PCR and sequence analysis. Prevalence of infection was 15% (3 of 20).Cytauxzoonsp. was only detected in Sierra Morena. For phylogenetic analysis, we used the sequences reported in the present study and those characterized in different domestic and wild felids and ticks from North and South America, Asia and Europe. Three differentCytauxzoonsp. sequences were obtained. They were closely related to that obtained from a Spanish cat, but diverged in up to 1·0% with respect to the only previously reported sequence from an Iberian lynx. Conversely, the latter sequence clustered together withC. manulsequences obtained from Pallas cats (Otocolobus manul) in Mongolia. Our analysis yields a separate cluster ofC. felissequences from cats, wild felids and ticks in the United States and Brazil. These results suggest that at least 2 differentCytauxzoonspp. may be present in Iberian lynx. The apparent absence in one of the areas, together with the possibility of fatal cytauxzoonosis in lynxes makes necessary disease risks to be taken into account in management conservation strategies, such as translocations and re-introductions.
Cryptic species ofDidymobothrium rudolphii(Cestoda: Spathebothriidea) from the sand sole,Solea lascaris, off the Portuguese coast, with an analysis of their molecules, morphology, ultrastructure and phylogeny
Authors: MARQUES J. F. , SANTOS M. J. , GIBSON D. I. , CABRAL H. N. , OLSON P. D.
Published: February 2007

Didymobothrium rudolphii(Cestoda: Spathebothriidea) was collected seasonally from the sand sole,Solea lascaris, off the northern, central and southern areas of the Portuguese coast. Morphological and molecular analyses were conducted in order to examine the possible existence of cryptic species and to facilitate the circumscription of their morphological boundaries. Data were compared betweenD. rudolphiispecimens from each of the 3 geographical areas and 4 seasons, and principal components analysis of 18 morphological characters was used to detect differences. Two distinct genotypes were present with sequence divergences of 1·9% and 2·1% in the large subunit (lsrDNA) and second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA), respectively. The less common ‘central’ genotype was present only off the central area from summer to winter, whereas the ‘common’ genotype was present throughout the year off the northern and southern areas, but only during spring in the central area. No sequence variation was found within each genotype. The presence of 2 distinct genetic entities was supported by morphological analyses, which showed the ‘central’ genotype specimens to be more slender and elongate, although morphometric ranges overlapped considerably for most characters. Molecular phylogenetic analysis of 4 of the 5 known genera of the Spathebothriidea showedSpathebothriumto be the earliest branching lineage and the 2 genotypes ofDidymobothriumformed a sister group toCyathocephalus. The concordance of genetic differences with variation in host diet according to season and locality could account for sympatric speciation occurring in the central region of the Portuguese coast.
Recent experiments on the hydrodynamics of laser-produced plasmas conducted at the PALS laboratory
Authors: BATANI D. , DEZULIAN R. , REDAELLI R. , BENOCCI R. , STABILE H. , CANOVA F. , DESAI T. , LUCCHINI G. , KROUSKY E. , MASEK K. , PFEIFER M. , SKALA J. , DUDZAK R. , RUS B. , ULLSCHMIED J. , MALKA V. , FAURE J. , KOENIG M. , LIMPOUCH J. , NAZAROV W. , PEPLER D. , NAGAI K. , NORIMATSU T. , NISHIMURA H.
Published: February 2007

We present a series of experimental results, and their interpretation, connected to various aspects of the hydrodynamics of laser produced plasmas. Experiments were performed using the Prague PALS iodine laser working at 0.44 μm wavelength and irradiances up to a few 1014W/cm2. By adopting large focal spots and smoothed laser beams, the lateral energy transport and lateral expansion have been avoided. Therefore we could reach a quasi one-dimensional regime for which experimental results can be more easily and properly compared to available analytical models.
An approach to hydrogen production by inertial fusion energy
Authors: IMASAKI K. , LI D.
Published: February 2007

An approach to produce efficient and economical hydrogen, which is one of the solutions of future energy, by inertial fusion energy reactor is discussed. This fusion reactor is with magnetic field such as mirror machine and graphite solid blanket. Neutrons and charged particles from nuclear reactions are separated from each other by this magnetic field. This results in hydrogen production efficiently in a solid blanket of high temperature with a breakeven of electricity by direct conversion of charged particle. The output of hydrogen may meet not only economical issue but also ecological issues.
Gametogenesis in the dragonfishes Akarotaxis nudiceps and Bathydraco marri (Pisces, Notothenioidei: Bathydraconidae) from the Ross Sea
Authors: La Mesa Mario , Caputo Vincenzo , Eastman Joseph T.
Published: February 2007

We analysed histological characteristics of gonads and reproductive effort of the small deep-living dragonfishes Akarotaxis nudiceps (Waite) and Bathydraco marri Norman collected in the south-western Ross Sea. From a macroscopic point of view, most specimens of B. marri were juveniles in early stages of gonad maturity, except for a maturing female. Conversely, the sample of A. nudiceps was composed of both immature and adult fish in different stages of maturity. A single A. nudiceps female was mature with a gonadosomatic index of 9.8%. Its absolute and relative fecundity was 260 oocytes and 31.5 oocytes g−1 TW, respectively, with a mean size of ripe oocytes of 1.9 mm. Gametogenesis in both species closely resembled that observed in other notothenioids, with females possessing two well-defined groups of oocytes. One group consisted of previtellogenic oocytes as a reserve stock while the other group was maturing oocytes to be ovulated in the current spawning season. A distinctive feature of oogenesis in recovering and maturing females of A. nudiceps was the presence of both postovulatory follicles in different stages of reabsorption and atretic oocytes. Based on low absolute fecundity, it is possible that A. nudiceps provides parental care and egg guarding.
Light environment and seasonal dynamics of microalgae in the annual sea ice at Terra Nova Bay, Ross Sea, Antarctica
Authors: Lazzara L. , Nardello I. , Ermanni C. , Mangoni O. , Saggiomo V.
Published: February 2007

We investigated the physical conditions of the Spring pack ice environment at Terra Nova Bay to understand their influence on the structure and physiology of sympagic microalgae. Bio-optical methods were used to study the availability and spectral quality of solar radiation, both inside and underneath the ice cover. Pack ice thickness was around 2.5 m, with a temperature between −2 and −7°C. On average, only 1.4% of surface PAR penetrated to the bottom ice and less than 0.6% below platelet ice level. Surface UV-B radiation under the bottom ice was 0.2–0.4%. Biomass concentrations up to 2400 mg Chl a m−3, dominated by two species of diatoms (Entomoneis kjellmannii and Nitschia cf. stellata), showed marked spatial and temporal patterns. Maximum values were in the platelet ice during the first half of November, and in the bottom ice two weeks later. Strong shade adaptation characteristics emerged clearly and explained the relevant abundance of microalgae within the sea ice, with specific absorption coefficients (a*) as low as 0.005 m2 (mg Chl a)−1 and the photo-acclimation index (Ek) in the range of in situ irradiance. The biomass specific production values were low, around 0.12–0.13 mg C mg Chl a−1 h−1. The hypothesis suggesting bottom ice colonization by platelet ice microalgae is supported here.
Comparison of children's diets as reported by the child via the Youth/Adolescent Questionnaire and the parent via the Willett food-frequency questionnaire
Authors: Lamb Molly M , Ross Colleen A , Brady Heather L , Norris Jill M
Published: February 2007

Objective

A comparison of a parent-completed Willett food-frequency questionnaire (FFQ) and a self-completed Youth/Adolescent Questionnaire (YAQ) has not yet been conducted.

Setting

In the Diabetes Autoimmunity Study in the Young (DAISY), parents report their child's diet on the FFQ annually from birth until age 10 years, when the child begins to report their own diet using the YAQ.

Subjects

To determine the comparability of these collection methods, 89 children aged 10–17 years and their parents completed the YAQ and FFQ, respectively, for the child's previous year's diet.

Design

We compared reported intakes for energy, the macronutrients and a variety of micronutrients of interest to the DAISY study.

Results

Bland–Altman plots of energy-adjusted differences between questionnaire responses against their means suggested that the two collection methods gave similar results. The average Spearman correlation coefficient of all energy-adjusted nutrient intakes was 0.50, and did not differ significantly by gender (males, r = 0.48; females, r = 0.46) or age (10–11 years, r = 0.49; 12–17 years, r = 0.51). While correlated, the nutrient values from the FFQ were higher than the nutrient values from the YAQ.

Conclusions

While reported nutrient intakes are correlated, an indicator variable defining which survey method a nutrient was collected with should be included in any longitudinal data analyses examining nutrient intakes collected with the YAQ and the FFQ as independent predictors of a disease outcome.
On the applicability of the Aristotelian principles to the definition of life
Authors: Kolb Vera M.
Published: February 2007

Despite numerous attempts, we still do not have a satisfactory definition of life. It is generally accepted that one of the essential features of life is the ability of an organism to reproduce. This implies that mules, workers ants, and other sterile individuals are not alive. To correct this apparent problem, we suggest that life should be defined in two ways. First, we define life as a phenomenon, for which the reproduction of some, but not all, individuals is essential. Second, we define life as a set of characteristics of an individual organism, among which reproduction is not essential. We explore Aristotle's classifications of things that exist, in which he placed individual living beings as primary substances, above their species and genera, which are considered secondary substances. The definition of life as a phenomenon needs to link life to its origins. Life presumably emerged from abiotic matter via chemical evolution. We have examined Aristotle's concept of change in which potentiality goes to actuality, and its variant, Kauffman's concept of ‘adjacent possible’, for their possible application in prebiotic chemical evolution. We have found that these principles are somewhat useful in the back-engineering process, but that they have very little predictive value. We have also considered whether viruses should be considered alive, and have pointed to the need for astrobiology to include viruses in its studies.