bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic sonography after first‐trimester Down syndrome screening
Authors: Krantz D. A. , Hallahan T. W. , Macri V. J. , Macri J. N.
Published: May 2007

Objective

Approximately 90% of Down syndrome cases are detected during first‐trimester screening. We aimed to determine the potential effectiveness of second‐trimester genetic sonography as a sequential screen for Down syndrome.

Methods

In this simulation study, published statistical parameters for first‐trimester free β‐human chorionic gonadotropin, pregnancy‐associated plasma protein‐A and nuchal translucency thickness, and second‐trimester ultrasound markers (nuchal fold, hyperechoic bowel, short humerus, short femur, echogenic intracardiac focus, pyelectasis and major abnormality) were used to model the effectiveness of second‐trimester genetic sonography combined with first‐trimester screening.

Results

First‐trimester combined screening alone resulted in a detection rate of 88.5% with a 4.2% false‐positive rate. A follow‐up genetic ultrasound examination in which only one sonographic marker was found and previous results were not taken into account would detect an additional 8% of Down syndrome cases for an additional false‐positive rate of 13.2%. Using individual marker likelihood ratios to modify the first‐trimester risk for screen‐negative patients, genetic sonography detected an additional 6.1% of Down syndrome cases for an additional 1.2% false‐positive rate, giving a total detection rate of 94.6% and a total false‐positive rate of 5.4%. In a contingent protocol, in which genetic sonography would be performed only for patients with a first‐trimester risk of between 1/300 and 1/2500, the detection rate was 4.8% and the false‐positive rate was 0.7%, giving a total detection rate of 93.3% and a total false‐positive rate of 4.9%.

Conclusion

Second‐trimester genetic sonography, if used properly, can be an effective sequential screen following first‐trimester Down syndrome screening. Further studies on the role of the genetic sonogram as a follow‐up to first‐trimester combined screening are warranted. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Frontomaxillary facial angle at 11 + 0 to 13 + 6 weeks: effect of plane of acquisition
Authors: Plasencia W. , Dagklis T. , Pachoumi C. , Kolitsi E. , Nicolaides K. H.
Published: May 2007

Objective

To determine the range of positions of the fetal head in which a three‐dimensional (3D) volume is acquired for subsequent successful assessment of the frontomaxillary facial (FMF) angle.

Method

We obtained 3D volumes of the fetal head at 11 + 0 to 13 + 6 weeks. The volumes were acquired with the head in different positions and reconstructed to obtain a mid‐sagittal section and demonstrate the maxilla, palate and frontal bone, which constitute the landmarks for the assessment of the FMF angle.

Results

In the reconstructed mid‐sagittal sections, it was possible to demonstrate the landmarks that define the FMF angle in most of the cases when the 3D volume acquisition plane was: (a) mid‐sagittal, with the angle between the face of the transducer and the direction of the fetal nose being about 0–99°, 150–199° and 330–359°; (b) transverse at the level of the biparietal diameter when the angle between the transducer and the midline echo of the brain was 0–29°; and (c) oblique around the crown–rump axis when the angle from the mid‐sagittal plane was 0–49°. However, the measurement of the FMF angle was artificially increased when in the mid‐sagittal plane the angle was 40–99° and 150–199°.

Conclusion

Successful assessment of the FMF angle by 3D ultrasound is dependent on the plane and angle of the volume acquisition. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Exploiting caching in heterogeneous mobile environment
Authors: Chand Narottam , Joshi R. C. , Misra Manoj
Published: May 2007

Sparse connectivity, limited energy, and restricted memory of Mobile Hosts (MHs) are the main characteristics of today's Mobile Ad hoc NETwork (MANET). Present wireless technology is now enabling MHs not only to have multi‐hop communication among themselves, but also to have direct connection with an Access Point (AP) also. The emergence of such heterogeneous technologies brings cooperative caching to reality wherein MHs can access data items from caches at MHs in their neighborhood and can drastically minimize query latency. This key technique reduces the number of uplink channel requests, alleviates server load, and increases data availability. In this paper, we assume a heterogonous mobile environment where combination of ad hoc communication and infrastructured APs can be used to better manage the data needs of MHs through cooperative caching. We call such an environment as Cooperation‐based Access Point MANET (CAPMANET). We present a Hop‐Oriented Cooperative Caching (HOCC) scheme for CAPMANET which helps in reducing the communication overhead and the query latency. HOCC employs a hybrid Pull with Push (PwP) mechanism to maintain data consistency. Simulation results demonstrate that HOCC outperforms the pure push and pure pull‐based strategies by taking advantages of underlying characteristics and avoiding associated weaknesses. Copyright © 2007 John Wiley & Sons, Ltd.
An adaptive energy‐efficient and low‐latency MAC for tree‐based data gathering in sensor networks
Authors: Lu Gang , Krishnamachari Bhaskar , Raghavendra Cauligi S.
Published: May 2007

A specific characteristic of sensor network applications is that the major traffic consists of data collection from various sensor source nodes to a sink via a unidirectional tree. In this paper, we propose DMAC, an energy efficient and low latency MAC that is designed and optimized for such data gathering trees in wireless sensor networks. We first show that previously proposed MAC protocols for sensor networks that utilize activation/sleep duty cycles suffer from a data forwarding interruption problem, whereby not all nodes on a multihop path to the sink can be notified of data delivery in progress, resulting in significant sleep delay. DMAC is designed to solve the interruption problem, by giving the active/sleep schedule of a node an offset that depends upon its depth on the tree. This scheme allows continuous packet forwarding because all nodes on the multihop path can be notified of the data delivery in progress. DMAC also adjusts node duty cycles adaptively according to the traffic load in the network by varying the number of active slots in an schedule interval. We further propose a data prediction mechanism and the use of more to send (MTS) packets in order to alleviate problems pertaining to channel contention and collisions. Our simulation results as well as experimental results with the Mote platform show that by exploiting the application‐specific structure of data gathering trees in sensor networks, DMAC provides significant energy savings and latency reduction while ensuring high data reliability. Copyright © 2007 John Wiley & Sons, Ltd.
The mitochondrial genome from the thermal dimorphic fungus Paracoccidioides brasiliensis
Authors: Cardoso Maria Angélica G. , Tambor José Humberto M. , Nobrega Francisco G.
Published: May 2007

We present here the sequence of the mitochondrial DNA of the pathogenic thermodimorphic fungus Paracoccidioides brasiliensis, agent of an endemic disease in most South American countries. The sequenced genome has 71 334 bp and is organized as a circular molecule with two gaps of unknown size flanking the middle exon of the nad5 gene. We located genes coding for the three subunits of the ATP synthase (atp6, atp8 and atp9), the apocytochrome b (cob), three subunits of the cytochrome c oxidase enzyme complex (cox1, cox2 and cox3), seven subunits of the reduced nicotinamide adenine dinucleotide ubiquinone oxidoreductase (nad1, nad2, nad3, nad4, nad5, nad6 and nad4L) and the large (rnl) and small (rns) subunits of ribosomal RNA. Two maturases and a ribosomal protein (rms5) are located inside introns. Twenty‐five tRNAs were identified with acceptors for all 20 amino acids. Seven polypurine/polypyrimidine tracts (140–240 bp) have been found in this genome. All genes are in the same orientation over the genome, while their order is closest to the mitochondrial genomes from Penicillium marneffei and Aspergillus nidulans. This sequence is available under GenBank Accession No. AY955840. Copyright © 2007 John Wiley & Sons, Ltd.
Providing a Transcultural Genetic Counseling Service in the UK
Authors: Middleton Anna , Robson Fiona , Burnell Liza , Ahmed Mushtaq
Published: May 2007

This paper uses a broad definition of culture to explore the practice of transcultural genetic counseling through three case studies. The first case involves a White genetic counselor seeing an Asian family, the second, an Asian genetic counselor seeing an Asian family and the third, a hearing genetic counselor seeing a culturally Deaf client. Boundaries, transference and countertransference reactions are considered within each transcultural encounter and the author of each case reflects in detail on their role in the client interaction and their impact on the transcultural dynamic. The cases are used to illustrate some cultural beliefs or characteristics that may challenge the genetic counselor's expectations. The value of identifying and interpreting these differences to facilitate useful clinical work is considered. The paper debates, where possible, whether it is helpful to culturally match genetic counselor and client.
Stigmatization, Culture and Counseling A Commentary on Growing Up and Living with NF1: a UK–Bangladeshi Case Study—by Santi Rozario
Authors: Gaff Clara L. , Clarke Angus
Published: May 2007

Rozario's presentation of the cultural manifestations of stigma experienced by a British Bangladeshi woman with Neurofibromatosis 1 (NF1) is unusual in its detail of one woman's account of others’ interactions with her and the impact on her life. It raises issues that are readily recognisable to genetic counselors and are familiar themes in the literature on the psychology of appearance. We draw on the genetics literature and on a body of expertise in research on the psychology of visible difference to consider the role of the genetic counselor in response to expressions of stigmatization or poor self‐esteem by those with a visible difference caused by a genetic condition.
Cholesterol Oxidation is Increased and PUFA Decreased by Frozen Storage and Grilling of Atlantic Hake Fillets (Merluccius hubbsi)
Authors: Saldanha Tatiana , Bragagnolo Neura
Published: May 2007

Fresh fillets of Atlantic hake were stored at −18 °C for 120 days and changes in lipid composition and the formation of cholesterol oxidation products (COP) during storage and subsequent grilling were evaluated. Fresh hake showed low COP levels (8.0 μg/g, dry basis); however, a significant increase in COP (P < 0.02) and a concomitant decrease in the cholesterol and polyunsaturated fatty acids content during frozen storage and after grilling were observed. The main cholesterol oxides present in the analyzed samples were: 19‐Hydroxycholesterol, 24(S)‐hydroxycholesterol, 22(S)‐hydroxycholesterol, 25‐hydroxycholesterol, 25(R)‐hydroxycholesterol and 7‐Ketocholesterol. The oxides which were more influenced by the thermal treatment were 24(S)‐OH and 25(R)‐OH; however, after 120 days of storage 7‐ketocholesterol was the main product formed. Frozen storage and subsequent grilling under domestic conditions are important factors in damage of cholesterol and unsaturated fatty acids levels, with consequent production of cholesterol oxides, although the mechanism of the formation of these compounds by the different processes is probably different.
Lipid Content and Fatty Acid Composition of 15 Marine Fish Species from the Southeast Coast of Brazil
Authors: Visentainer Jesuí Vergílio , Noffs Maximiliano D'Addio , de Oliveira Carvalho Patricia , de Almeida Vanessa Vivian , de Oliveira Cláudio Celestino , de Souza Nilson Evelázio
Published: May 2007

Lipid content and fatty acid composition were determined in edible meat of fifteen marine fish species caught on the Southeast Brazilian coast and two from East Antarctic. Most of the fish had lipid amounts lower than 10% of their total weight. Palmitic acid (C16:0) predominated, accounting for 54–63% of the total amount of saturated fatty acids. Oleic acid (C18:1n‐9) was the most abundant (49–69%) monounsaturated fatty acid, and docosahexaenoic acid (DHA) was the predominant polyunsaturated fatty acid (PUFA), accounting for 31–84% of n‐3 PUFA. n‐3 PUFA level were highest in Antarctic fish meat, comprising 45% of the total fatty acid content, which consisted of mainly EPA (16.1 ± 1.5 g/100 g lipids) and DHA (24.8 ± 2.4 g/100 g lipids). The amounts of EPA + DHA in g/100 g of lipids on the Southeast Brazilian coast and Antarctic fish species investigated were found to be similar: 42.0 ± 1.7 for Bonito cachorro, 41.0 ± 2.3 for Atum, and 39.4 ± 1.8 for peixe porco, respectively. All the studied species exhibited an n‐3/n‐6 ratio higher than 3, which confirms the great importance of Southeast Brazilian coast fish as a significant dietary source of n‐3 PUFA.
Expression of human leukocyte antigen‐G and its correlation with interleukin‐10 expression in cervical carcinoma
Authors: Yoon B.S. , Kim Y.T. , Kim J.W. , Kim S.H. , Kim J.H. , Kim S.W.
Published: May 2007

Objective: To determine human leukocyte antigen (HLA)‐G and interleukin (IL)‐10 expression and the relationship between HLA‐G expression and clinicopathologic features in patients with cervical cancer. Method: Tissue samples were obtained from 40 patients with cervical cancer and 15 control patients with a normal cervix. Quantitative real‐time RT‐PCR for mRNA and western blot analysis for protein expression were used. Result: Both HLA‐G and IL‐10 mRNA expression in cervical cancer tissues was significantly greater than normal controls (P < 0.001, P = 0.005). Protein expression of HLA‐G and IL‐10 in the cancer group was also significantly greater than in the controls (P < 0.001, P = 0.021). There was an inverse relationship between FIGO stage and HLA‐G mRNA expression (P = 0.046). Conclusion: HLA‐G and IL‐10 might play an important role in cancer progression of the cervix. High HLA‐G mRNA expression may be related to early carcinogenesis since it was associated with early‐stage cervical cancer.
Method of placental removal during cesarean delivery and postpartum complications
Authors: Merchavy S. , Levy A. , Holcberg G. , Freedman E.N. , Sheiner E.
Published: May 2007

Objective: The study was aimed to determine whether the method of placental removal at the time of the cesarean delivery is associated with postpartum complications such as postpartum fever and wound infection. In addition it was aimed to identify other complications following cesarean delivery. Methods: A prospective observational study was conducted, including 426 women who underwent cesarean deliveries between January 2004 and March 2005, in a tertiary medical center. A multivariable logistic regression model, with backward elimination, was constructed in order to identify independent risk factors associated with the occurrence of wound infection or fever. A sample size of about 150 subjects in each group was needed to demonstrate a difference of 15% between the two methods of placental removal, with a probability of 95% and power of 80%. Results: Manual removal of the placenta occurred in 269 operations while in 157 women the placenta was removed in a spontaneous method. No statistically significant differences were noted between the two methods of removal of the placenta regarding the risk for fever (7.8% in the group of the manual removal, as compared with 5.1% in the group of the spontaneous method; P = 0.284) or for wound infection (3.7% in the group of the manual removal compared with 5.1% in the group of the spontaneous method; P = 0.495). Using a multivariable logistic regression model, with backward elimination, the following risk factors were identified for postcesarean fever, or wound infection: unskilled surgeon (OR 3.2, 95% CI 1.4–7.8), number of previous cesarean deliveries (OR 1.8, 95% CI 1.3–2.6) and maternal hypertension (OR 3.3, 95% CI 2.0–38.5). Conclusion: The method of placental removal during cesarean delivery is not associated with the risk for either wound infection or postpartum fever.
Highly neurotic never-depressed students have negative biases in information processing
Authors: CHAN STELLA W. Y. , GOODWIN GUY M. , HARMER CATHERINE J.
Published: May 2007

Background

Cognitive theories associate depression with negative biases in information processing. Although negatively biased cognitions are well documented in depressed patients and to some extent in recovered patients, it remains unclear whether these abnormalities are present before the first depressive episode.

Method

High neuroticism (N) is a well-recognized risk factor for depression. The current study therefore compared different aspects of emotional processing in 33 high-N never-depressed and 32 low-N matched volunteers. Awakening salivary cortisol, which is often elevated in severely depressed patients, was measured to explore the neurobiological substrate of neuroticism.

Results

High-N volunteers showed increased processing of negative and/or decreased processing of positive information in emotional categorization and memory, facial expression recognition and emotion-potentiated startle (EPS), in the absence of global memory or executive deficits. By contrast, there was no evidence for effects of neuroticism on attentional bias (as measured with the dot-probe task), over-general autobiographical memory, or awakening cortisol levels.

Conclusions

These results suggest that certain negative processing biases precede depression rather than arising as a result of depressive experience per se and as such could in part mediate the vulnerability of high-N subjects to depression. Longitudinal studies are required to confirm that such cognitive vulnerabilities predict subsequent depression in individual subjects.
Suicide in Bahrain in the Last Decade
Authors: Al Ansari Ahmed , Hamadeh Randah R. , Ali Mazin K. , El Offi Adel
Published: May 2007

Abstract. A combination of social, legal, and religious factors make reporting of suicide difficult in Bahrain, an Islamic country. Limited available data indicates a very low incidence rate of 3 per 100,000. The objective of the present study was to describe the pattern of suicide in Bahrain during a 10-year period. The registered suicide cases (N = 304) at the Ministry of Interior for the 10-year period from 1995 to 2004 were reviewed and analyzed. The mean suicide rate was 0.6 per 100,000 for the Bahraini nationals and 12.6 per 100,000 for the non-Bahrainis with and 17.7 per 100,000 for the Indian migrants. Men were six times more likely than women to commit suicide. The majority of the subjects were under 35 years of age with financial domestic problems being the most common reason reported in the record and hanging the mostly commonly used mode of suicide (92.8%). The suicide rate for the Bahraini population remains low compared to other countries. The higher rate of suicide among Indians merits further investigation. Moreover, more research is needed on the epidemiology of suicide risk factors in ethnic groups for further prevention and intervention.
Outcome of Suicidal Ideation and Behavior in a Young, Help-Seeking Population over a 2-Year Period
Authors: Cosgrave E.M. , Robinson J. , Godfrey K.A. , Yuen H.P. , Killackey E.J. , Baker K.D. , Buckby J.A. , Yung A.R.
Published: May 2007

Abstract. Suicidal behavior is associated with negative outcomes, including completed suicide. This study examined the prevalence of suicidal behavior in a sample of referrals to a youth psychiatric service and investigated the stability of suicidality over 2 years. Of the 140 people (mean age 17.8) who were referred to a youth psychiatric service, 82 who were accepted for treatment (RA group) and 58 who were not accepted (RNA group) were assessed; 57% reported considering suicide and 39% reported attempting suicide in the 12 months prior to referral. Participants who reported suicidal ideation were significantly more likely than nonsuicidal participants to have multiple Axis I diagnoses and lower levels of functioning. At the 2-year follow-up there was a significant reduction in suicidality in the RA group, but not in the RNA group. In conclusion, suicidality is prevalent among young people referred to psychiatric services. Even brief contact with services results in a reduction in suicidality over 2 years.
Body Mass and Suicide Risk
Authors: Stack Steven , Lester David
Published: May 2007

Abstract. Body mass has been neglected as a possible predictor of suicidal behavior. The present investigation explores the association between body mass index and completed suicide. Data are from the National Mortality Followback Survey and refer to 373 suicides, and 518 deaths from motor vehicle accidents as controls. The results of a logistic regression analysis indicated that, for females, the greater the BMI the greater the suicide risk. However, this relationship did not hold up under controls for race and other covariates of BMI. For males, the BMI was not significantly related to suicide risk either at the bivariate or multivariate levels of analysis. The best predictors of suicide were living alone for females, and alcohol abuse for males.
Climatic and tectonic controls on weathering in south China and Indochina Peninsula: Clay mineralogical and geochemical investigations from the Pearl, Red, and Mekong drainage basins
Authors: Liu Zhifei , Colin Christophe , Huang Wei , Le Khanh Phon , Tong Shengqi , Chen Zhong , Trentesaux Alain
Published: May 2007

Results of clay mineralogy, major element geochemistry, and Sr and Nd isotopes in 93 argillaceous samples collected from drainage basins of the Pearl, Red, and Mekong rivers reveal different degrees of chemical weathering in Southeast Asia despite similar climate conditions across these regions. The kaolinite/illite ratio, illite chemistry index, and illite crystallinity can be used as indicators of chemical weathering intensity. These mineralogical proxies combined with the K2O/(Na2O + CaO) molar ratio, chemical index of alteration (CIA), and weathering trends observed from major element results indicate intensive silicate weathering in the Pearl River basin, moderate to intensive in the Mekong River basin, and moderate in the Red River basin. Although a significant modification of ɛNd(0) values in our riverine sediments during chemical weathering and transport is unlikely,87Sr/86Sr ratios are controlled by various states of chemical weathering of high‐Sr minerals such as plagioclase (rich in Na and Ca) with a linear decrease trend from the Pearl, Mekong, to Red river basins. Our results suggest that it is not the warm climate with heavy monsoon precipitation but tectonics playing the most significant role in controlling weathering and erosion processes in south China and Indochina Peninsula. Strong physical erosion caused by tectonic activities and river incision along the eastern margin of the Tibetan Plateau and along the Red River fault system is responsible for high contents of primary minerals in the lowlands of Red and Mekong river basins.
Measuring turbulent heat fluxes over leads using kites
Authors: Guest Peter S.
Published: May 2007

During the MaudNESS project in the austral winter of 2005, radiosondes attached to a kite indirectly measured surface turbulent heat fluxes from leads in the Eastern Weddell Sea near Maud Rise. Kite flights over two different leads with similar widths and upwind ice conditions are discussed. Lead mean surface fluxes were estimated by measuring the excess temperature and humidity downwind of the leads, estimating the wind speed profiles and performing a heat and moisture budget quantification. The measured sensible (latent) heat fluxes were 318 Wm−2 (158 Wm−2) and 258 Wm−2 (85 Wm−2) for the two flights; the values were lower in the second flight due to lower wind speeds. The average neutral sensible heat transfer coefficients for the two flights was (1.48 ± 0.13) × 10−3, and the average neutral latent heat flux coefficient was (1.47 ± 0.09) × 10−3. As expected, these values are enhanced from what would be expected in a typical open ocean situation with the same air‐sea temperature and humidity differences. Kite radiosonde profile measurements are an economically viable method for measuring lead heat fluxes that avoid many of the logistical problems associated with other methods for measuring fluxes over leads.
New particle formation in Beijing, China: Statistical analysis of a 1‐year data set
Authors: Wu Zhijun , Hu Min , Liu Shang , Wehner Birgit , Bauer Stefan , Ma ßling Andreas , Wiedensohler Alfred , Petäjä Tuukka , Dal Maso Miikka , Kulmala Markku
Published: May 2007

Particle number size distributions between 3 nm and 10 μm were measured in Beijing, China. New particle formation events were observed on around 40% of the measurement days from March 2004 to February 2005 and were generally observed under low relative humidity and sunny conditions. Though occurring during all seasons, new particle formation events had highest frequency in spring and lowest frequency in summer. Events were classified as “clean” or “polluted” groups mainly according to the condensational sink and the local wind. The formation rate range was from 3.3 to 81.4 cm−3 s−1. The growth rate varied from 0.1 to 11.2 nm h−1. The seasonal variation of condensable vapor concentration showed the highest values during summer months due to enhanced photochemical and biological activities as well as stagnant air masses preventing exchange with cleaner air.
Air mass classification in coastal New England and its relationship to meteorological conditions
Authors: Chen Ming , Talbot Robert , Mao Huiting , Sive Barkley , Chen Jianjun , Griffin Robert J.
Published: May 2007

The dominant air mass types along coastal New England during summer 2004 were classified and their relationship to synoptic meteorological conditions investigated as a component of the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign. Representative air mass types were defined on the basis of variability in the occurrence of volatile organic compounds (VOCs), and they were further grouped into distinct source‐related categories. Emissions from nearby anthropogenic sources were found to govern the total variance of the data set (58% at Appledore Island (AI) and 56% at Thompson Farm (TF)), whereas long‐distance transport was much less dominant (15% on AI and 17% at TF). This result indicates frequent influence from recent anthropogenic emissions at TF and AI, with periodic inputs of aged/processed pollutants. The fractional time periods dominated by anthropogenic (recent and aged/processed) and marine biogenic air masses were almost the same at TF and AI (36% versus 30% and 14% versus 16% respectively), clearly showing the strong impact of continental outflow on the nearshore marine atmosphere and a surprising persistent influence of marine biogenic emissions at an inland site. Empirical orthogonal function (EOF) analysis suggested that the most important circulation pattern during summer 2004 was characterized by a low trough positioned along coastal New England, leaving this region under the control of northwesterly flow from central Canada. This result helps explain why New England in summer 2004 was less polluted compared to previous years.
Summertime influence of Asian pollution in the free troposphere over North America
Authors: Liang Q. , Jaeglé L. , Hudman R. C. , Turquety S. , Jacob D. J. , Avery M. A. , Browell E. V. , Sachse G. W. , Blake D. R. , Brune W. , Ren X. , Cohen R. C. , Dibb J. E. , Fried A. , Fuelberg H. , Porter M. , Heikes B. G. , Huey G. , Singh H. B. , Wennberg P. O.
Published: May 2007

We analyze aircraft observations obtained during INTEX‐A (1 July to 14 August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and principal component analysis (PCA) to the observations between 6 and 12 km, we find dominant influences from recent convection and lightning (13% of observations), Asia (7%), the lower stratosphere (7%), and boreal forest fires (2%), with the remaining 71% assigned to background. Asian air masses are marked by high levels of CO, O3, HCN, PAN, C2H2, C6H6, methanol, and SO42–. The partitioning of NOy species in the Asian plumes is dominated by PAN (∼600 pptv), with varying NOx/HNO3 ratios in individual plumes, consistent with individual transit times of 3–9 days. Export of Asian pollution occurred in warm conveyor belts of midlatitude cyclones, deep convection, and in typhoons. Compared to Asian outflow measurements during spring, INTEX‐A observations display lower levels of anthropogenic pollutants (CO, C3H8, C2H6, C6H6) due to shorter summer lifetimes; higher levels of biogenic tracers (methanol and acetone) because of a more active biosphere; and higher levels of PAN, NOx, HNO3, and O3 reflecting active photochemistry, possibly enhanced by efficient NOy export and lightning. The high ΔO3/ΔCO ratio (0.76 mol/mol) in Asian plumes during INTEX‐A is due to strong photochemical production and, in some cases, mixing with stratospheric air along isentropic surfaces. The GEOS‐Chem global model captures the timing and location of the Asian plumes. However, it significantly underestimates the magnitude of observed enhancements in CO, O3, PAN and NOx.
Modeling water ice lifetimes at recent Martian gully locations
Authors: Williams K. E. , Toon O. B. , Heldmann J.
Published: May 2007

Mars Global Surveyor identified two instances of recent changes in gully morphology. Images suggest that two gullies had recent discharges of some liquid, leaving a residue behind. The residue might be water ice mixed with dust. We applied a thermodynamic model to these two locations to determine the lifetime of the hypothetical water ice. We find that a very dusty 2m‐thick icepack of moderate density would completely disappear within 1–2 Mars years by sublimation. If the bright deposits are actually ice then we would expect to see them absent in images taken several Mars years from now, unless they are being replenished.
Multidecadal variability in the transmission of ENSO signals to the Indian Ocean
Authors: Shi G. , Ribbe J. , Cai W. , Cowan T.
Published: May 2007

Since 1980, transmission of El Niño‐Southern Oscillation (ENSO) signals into the Indian Ocean involves an equatorial, and a subtropical North Pacific (NP) Rossby wave pathway. We examine the robustness of the amount of energy that leaves the Pacific via each of the pathway using the Simple Ocean Data Assimilation with the Parallel Ocean Program (SODA‐POP) reanalysis and a multi‐century coupled model control experiment. We find that in the pre‐1980 period, little ENSO signal is transmitted to the Indian Ocean and does not involve the subtropical NP pathway. Such multidecadal variability is periodically produced by the climate model. Examinations reveal that when ENSO is weak as determined by Niño3.4, their meridional extent is narrow, the associated discharge‐recharge does not involve the subtropical NP pathway; further, weak ENSO events have a low signal‐to‐noise ratio, making the transmission hard to detect. The dynamics of multidecadal variability in ENSO strength awaits further investigation.
Differences in the composition of vaginal microbial communities found in healthy Caucasian and black women
Authors: Zhou Xia , Brown Celeste J , Abdo Zaid , Davis Catherine C , Hansmann Melanie A , Joyce Paul , Foster James A , Forney Larry J
Published: May 2007

The maintenance of a low pH in the vagina through the microbial production of lactic acid is known to be an important defense against infectious disease in reproductive age women. Previous studies have shown that this is largely accomplished through the metabolism of lactic acid bacteria, primarily species of Lactobacillus. Despite the importance of this defense mechanism to women's health, differences in the species composition of vaginal bacterial communities among women have not been well defined, nor is it known if and how these differences might be linked to differences in the risk of infection. In this study, we defined and compared the species composition of vaginal bacterial communities in 144 Caucasian and black women in North America. This was carried out based on the profiles of terminal restriction fragments of 16S rRNA genes, and phylogenetic analysis of 16S rRNA gene sequences of the numerically dominant microbial populations. Among all the women sampled, there were eight major kinds of vaginal communities (‘supergroups’) that occurred in the general populace at a frequency of at least 0.05 (P=0.99). From the distribution of these supergroups among women, it was possible to draw several conclusions. First, there were striking, statistically significant differences (P=0.0) in the rank abundance of community types among women in these racial groups. Second, the incidence of vaginal communities in which lactobacilli were not dominant was higher in black women (33%) as compared to Caucasian women (7%). Communities not dominated by lactobacilli had Atopobium and a diverse array of phylotypes from the order Clostridiales. Third, communities dominated by roughly equal numbers of more than one species of Lactobacillus were rare in black women, but common in Caucasian women. We postulate that because of these differences in composition, not all vaginal communities are equally resilient, and that differences in the vaginal microbiota of Caucasian and black women may at least partly account for known disparities in the susceptibility of women in these racial groups to bacterial vaginosis and sexually transmitted diseases.
New mixed quantum∕semiclassical propagation method
Authors: Antoniou Dimitri , Gelman David , Schwartz Steven D.
Published: May 2007

The authors developed a new method for calculating the quantum evolution of multidimensional systems, for cases in which the system can be assumed to consist of a quantum subsystem and a bath subsystem of heavier atoms. The method combines two ideas: starting from a simple frozen Gaussian description of the bath subsystem, then calculate quantum corrections to the propagation of the quantum subsystem. This follows from recent work by one of them, showing how one can calculate corrections to approximate evolution schemes, even when the Hamiltonian that corresponds to these approximate schemes is unknown. Then, they take the limit in which the width of the frozen Gaussians approaches zero, which makes the corrections to the evolution of the quantum subsystem depend only on classical bath coordinates. The test calculations they present use low-dimensional systems, in which comparison to exact quantum dynamics is feasible.
Magnetically driven filament probe
Authors: Schmid A. , Herrmann A. , Rohde V. , Maraschek M. , Müller H. W. ,   the ASDEX Upgrade Team
Published: May 2007

A radially movable probe has been developed for studies of filamentary transport in ASDEX Upgrade during edge localized modes (ELMs) by means of Langmuir tips and magnetic pickup coils. The probe is permanently installed at the low field side in the ASDEX Upgrade vacuum vessel and is not subject to limitations in probe size, as, for example, probes on a shared manipulator are. The probe is moved by a magnetic drive, which allows for easy installation in the vessel, and has moderate machine requirements, as it will only require an electric feedthrough and an external power supply. The drive gives a linear motion with a radial range of 5cm within 50ms, where range and velocity can be largely scaled according to experimental requirements. The probe has been installed in the outer midplane of the ASDEX Upgrade vessel, where ELM filaments are expected to have their maximum amplitude. Filaments are coherent substructures within an ELM, carrying a fraction of the ELM released energy towards the wall. The new probe allows to measure the structure of these filaments, in particular, parameters such as filament rotation (by time delay measurements) and size (by peak width analysis). Activating the drive moves the probe from a safe position behind the limiter to a position in front of the limiters, i.e., exposes the Langmuir pins to the scrape-off layer plasma.
High resolution gas volume change sensor
Authors: Dirckx Joris J. J. , Aernouts Jef E. F. , Aerts Johan R. M.
Published: May 2007

Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15measurements∕s and a resolution better than 0.06μl. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15Pa, and at constant change rates the pressure artifact is smaller than 10Pa or 0.01% of ambient pressure.
Feeding dynamics, consumption rates and daily ration of longtail tuna (Thunnus tonggol) in Australian waters, with emphasis on the consumption of commercially important prawns
Authors: Griffiths Shane P. , Fry Gary C. , Manson Fiona J. , Pillans Richard D.
Published: May 2007

The feeding ecology of longtail tuna was studied in northern and eastern Australia. Diet biomass data were used to estimate daily ration and consumption of individual prey taxa, particularly penaeids targeted by Australia’s valuable Northern Prawn Fishery (NPF). Overall, the 497 stomachs contained 101 prey taxa. In both regions, small pelagic and demersal fishes comprised the majority of the diet biomass. Fish in both regions showed a marked increase in prey diversity, variation in prey composition and stomach fullness index in autumn and winter (March–August). This increase in apparently opportunistic feeding behaviour and feeding intensity showed an inverse relationship with reproductive activity, indicating a possible energy investment for gonad development. Daily ration decreased with increasing fish size, while annual consumption by fish increased with size. Total prey consumption in the Gulf of Carpentaria was estimated at 148178 t year–1. This includes 599 t year-1 of penaeids, equivalent to 11% of the annual NPF catch. This study demonstrated that longtail tuna play an important ecological role in neritic ecosystems. Their interaction with commercial fisheries highlights the need for targeted dietary studies of high order predators to better understand trophic pathways to facilitate ecosystem-based fisheries management.
Patch history, invertebrate patch dynamics and heterogeneous community composition: perspectives from a manipulative stream experiment
Authors: Olsen D. A. , Matthaei C. D. , Townsend C. R.
Published: May 2007

Recent research after bed-moving flow events has shown that local disturbance history can contribute to patchiness in stream communities. Patterns of recolonisation were studied following experimental disturbances in which patches of sediment were manipulated by removing 10 cm of surface sediment (scour) or by depositing 10 cm of clean sediment (fill) on top of existing sediments. Six invertebrate samples were collected from each patch type (including stable control patches) on five occasions up to six weeks after the manipulation. Immediately after the disturbance, distinctive macroinvertebrate communities occurred in scour, fill and stable patches. Community composition in scour patches remained distinct from fill and stable patches for the entire study period. Immediately after the manipulation, scour patches contained higher densities of hypogean taxa than did fill patches, but this difference did not persist for long, indicating that the relict community had little influence on the subsequent pattern of recovery. In contrast, fill patch communities were indistinguishable from stable patches by Day 14, most likely owing to recolonisation by buried invertebrates and invertebrate drift. Differences in patterns of recolonisation following different types of disturbance can result in patchy invertebrate communities that persist for several weeks after the disturbance.
Optimisation of handling, activation and assessment procedures for Bufo marinus spermatozoa
Authors: Fitzsimmons C. , McLaughlin E. A. , Mahony M. J. , Clulow J.
Published: May 2007

In the present study, we investigated handling, activation and assessment procedures for cane toad (Bufo marinus) spermatozoa. Optimisation of these techniques will facilitate the maintenance of sperm viability during cryopreservation and during in vitro fertilisation (IVF) techniques in reproduction technologies for endangered species. Spermatozoa were taken from testicular macerates and assessed using plasma membrane integrity assays (live/dead stains) and quantitative scores of motility parameters. In the assessment of sperm viability using live/dead stains, there were small but significant differences in the percentage of sperm from cryopreserved samples staining positive with propidium iodide, Hoechst H33258 and Trypan blue; these differences were not large and all stains performed acceptably. Spermatozoa were activated by dilution of testicular macerates in water at one of two dilution ratios (1 : 6 or 1 : 20) with or without 0.1–5.0 mm theophylline. Sperm plasma membrane integrity (unstained spermatozoa) was unaffected by either dilution ratio (osmolarity) or theophylline concentration. However, sperm motility was significantly affected by osmolarity and theophylline concentration. The stimulation of sperm motility increased with higher theophylline concentrations and these strongly interacted with lower osmolarities through a higher dilution ratio of sperm macerates with water. Spermatozoa were exposed to increasing centrifugation forces to determine tolerance to physical stresses encountered during washing procedures. Forces between 50 and 800g were associated with a significant reduction in motility (mean 56 ± 3% decreasing to 27 ± 3%), but did not affect staining. In conclusion, centrifugation should be minimised in anuran sperm washing procedures; osmotic shock associated with higher dilution ratios reduces the capacity of anuran sperm to achieve high percentages of motile sperm, leading to a likely trade-off between dilution required for activation and sperm motility to optimise IVF fertilisation rates; and optimal conditions for sperm motility after activation occur at lower dilutions of suspensions with 5.0 mm theophylline. The present study has improved protocols for the handling of anuran sperm during pre- and post-cryopreservation procedures.
Effects of uteroplacental restriction on the relaxin-family receptors, Lgr7 and Lgr8, in the uterus of late pregnant rats
Authors: Vodstrcil Lenka A. , Wlodek Mary E. , Parry Laura J.
Published: May 2007

The peptide hormone relaxin stimulates uterine growth and endometrial angiogenesis and inhibits myometrial contractions in a variety of species. The receptor for relaxin is a leucine-rich repeat containing G-protein-coupled receptor Lgr7 (RXFP1) that is highly expressed in the myometrium of late pregnant mice, with a significant decrease in receptor density observed at term. The present study first compared the expression of Lgr7 with another relaxin-family receptor Lgr8 (RXFP2) in the uterus and placenta of late pregnant rats. The uterus was separated into endometrial and myometrial components, and the myometrium into fetal and non-fetal sites, for further analysis. We then assessed the response of these receptors to uteroplacental restriction (UPR). Expression of the Lgr7 gene was significantly higher in the uterus compared with the placenta. Within the uterus, on Day 20 of gestation, there was equivalent expression of Lgr7 in fetal and non-fetal sites of the myometrium, as well as in the endometrium v. myometrium. The second receptor investigated, Lgr8, was also expressed in the endometrium and myometrium, but at significantly lower levels than Lgr7. Bilateral ligation of the maternal uterine blood vessels on Day 18 of gestation resulted in uteroplacental restriction, a decrease in fetal weight and litter size, and a significant upregulation in uterine, but not placental, Lgr7 and Lgr8 gene expression in UPR animals compared with controls. These data suggest that both relaxin family receptors are upregulated in response to a reduction in uteroplacental blood flow in rats.
Single-molecule mass spectrometry in solution using a solitary nanopore
Authors: Robertson Joseph W. F. , Rodrigues Claudio G. , Stanford Vincent M. , Rubinson Kenneth A. , Krasilnikov Oleg V. , Kasianowicz John J.
Published: May 2007

We introduce a two-dimensional method for mass spectrometry in solution that is based on the interaction between a nanometer-scale pore and analytes. As an example, poly(ethylene glycol) molecules that enter a single α-hemolysin pore cause distinct mass-dependent conductance states with characteristic mean residence times. The conductance-based mass spectrum clearly resolves the repeat unit of ethylene glycol, and the mean residence time increases monotonically with the poly(ethylene glycol) mass. This technique could prove useful for the real-time characterization of molecules in solution.
ApoER2/VLDL receptor and Dab1 in the rostral migratory stream function in postnatal neuronal migration independently of Reelin
Authors: Andrade Nuno , Komnenovic Vukoslav , Blake Sophia M. , Jossin Yves , Howell Brian , Goffinet Andre , Schneider Wolfgang J. , Nimpf Johannes
Published: May 2007

Postnatal migration of interneuron precursors from the subventricular zone to the olfactory bulb occurs in chains that form the substrate for the rostral migratory stream. Reelin is suggested to induce detachment of neuroblasts from the chains when they arrive at the olfactory bulb. Here we show that ApoER2 and possibly very-low-density lipoprotein receptor (VLDLR) and their intracellular adapter protein Dab1 are involved in chain formation most likely independent of Reelin. F-spondin, which is present in the stream, may act as ligand for ApoER2 and VLDLR. In mice lacking either both receptors or Dab1 chain formation is severely compromised, and as a consequence the rostral migratory stream is virtually absent and neuroblasts accumulate in the subventricular zone. The mutant animals exhibit severe neuroanatomical defects in the subventricular zone and in the olfactory bulb. These data demonstrate a cell-autonomous function of ApoER2, and most likely VLDLR and Dab1, in postnatal migration of neuroblasts in the forebrain, which is suggested to depend on ligands other than Reelin.