bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful Psychotherapy Reduces Hypervigilance in Borderline Personality Disorder
Authors: Sieswerda Simkje , Arntz Arnoud , Kindt Merel
Published: May 2007

The aims of the present study were to investigate whether selective attention in borderline personality disorder (BPD) is content-specific and influenced by treatment. Comparisons were made between emotional Stroop interferences of stimulus types that were related and unrelated to hypothesized BPD schemas (1) of patients with BPD (n = 24) and nonpatient controls (n = 23), and (2) of BPD patients (n = 16) at start and end of an intensive, 3-year lasting treatment. Patients with BPD showed general hypervigilance, i.e. attentional biases for both schema related and unrelated emotional stimuli. Hypervigilance was completely reduced to normalized levels in recovered patients (n = 6), but not in non-recovered patients (n = 10) at the end of treatment. The findings support the possibility of structural change in BPD.
Breast-feeding mothers can exercise: results of a cohort study
Authors: Su Dada , Zhao Yun , Binns Colin , Scott Jane , Oddy Wendy
Published: May 2007

Objectives

To study the relationship between exercise by the mother and breast-feeding initiation and duration, and its effect on infant growth.

Design

A cohort study of mothers and infants, recruited at birth. Infant feeding methods were recorded in detail and breast-feeding was categorised as ‘any’ or ‘full’. Exercise levels were categorised using the metabolic equivalent tasks approach based on details of physical activity recorded in questionnaires.

Setting

Perth, Western Australia.

Subjects

A total of 587 mothers were interviewed on seven occasions over a period of 12 months.

Results

There was no difference in the means of infant weight and length changes, indicating that exercise appeared to have no significant influence on infant growth up to 52 weeks after birth (P = 0.236 and 0.974, respectively). The mother's level of exercise was not significantly associated with breast-feeding to 6 or 12 months. This applied to ‘full’ and ‘any’ categories of breast-feeding.

Conclusion

Exercise does not affect breast-feeding outcomes at the usual levels of activity undertaken by mothers. Breast-feeding and exercise are important for maintaining and promoting health, and this study provides reassurance to health professionals wishing to encourage mothers to continue both behaviours.
For the use of ultrasound by surgeons
Authors: Dixon J. Michael , Macaskill E. Jane
Published: May 2007

There is an increasing demand upon radiology departments for use of ultrasound as part of triple assessment of symptomatic breast disease. It has been shown that in the context of proper training both surgeons and radiologists achieve comparably high diagnostic sensitivity and specificity with ultrasound. This article outlines the arguments in favour of the use of ultrasound by surgeons in the breast clinic for diagnostic and therapeutic purposes.
Improving Prolog programs: Refactoring for Prolog
Authors: SEREBRENIK ALEXANDER , SCHRIJVERS TOM , DEMOEN BART
Published: May 2007

Refactoring is an established technique from the object-oriented (OO) programming community to restructure code: it aims at improving software readability, maintainability, and extensibility. Although refactoring is not tied to the OO-paradigm in particular, its ideas have not been applied to logic programming until now. This paper applies the ideas of refactoring to Prolog programs. A catalogue is presented listing refactorings classified according to scope. Some of the refactorings have been adapted from the OO-paradigm, while others have been specifically designed for Prolog. The discrepancy between intended and operational semantics in Prolog is also addressed by some of the refactorings. In addition, ViPReSS, a semi-automatic refactoring browser, is discussed and the experience with applying ViPReSS to a large Prolog legacy system is reported. The main conclusion is that refactoring is both a viable technique in Prolog and a rather desirable one.
A possible biogenic origin for hydrogen peroxide on Mars: the Viking results reinterpreted
Authors: Houtkooper Joop M. , Schulze-Makuch Dirk
Published: May 2007

The adaptability of extremophiles on Earth raises the question of what strategies putative life might have used to adapt to the present conditions on Mars. Here, we hypothesize that organisms might utilize a water–hydrogen peroxide (H2O–H2O2) mixture rather than water as an intracellular liquid. This adaptation would have the particular advantages in the Martian environment of providing a low freezing point, a source of oxygen and hygroscopicity. The findings by the Viking experiments are reinterpreted in light of this hypothesis. Our conclusion is that the hitherto mysterious oxidant in the Martian soil, which evolves oxygen when humidified, might be H2O2of biological origin. This interpretation has consequences for site selection for future missions to search for life on Mars.
Canopy structure and imaging geometry may create unique problems during spectral reflectance measurements of crop canopies in bioregenerative advanced life support systems
Authors: Schuerger Andrew C. , Copenhaver Kenneth L. , Lewis David , Kincaid Russell , May George
Published: May 2007

Human exploration missions to the Moon or Mars might be helped by the development of a bioregenerative advanced life-support (ALS) system that utilizes higher plants to regenerate water, oxygen and food. In order to make bioregenerative ALS systems competitive to physiochemical life-support systems, the ‘equivalent system mass’ (ESM) must be reduced by as much as possible. One method to reduce the ESM of a bioregenerative ALS system would be to deploy an automated remote sensing system within plant production modules to monitor crop productivity and disease outbreaks. The current study investigated the effects of canopy structure and imaging geometries on the efficiency of measuring the spectral reflectance of individual plants and crop canopies in a simulated ALS system. Results indicate that canopy structure, shading artefacts and imaging geometries are likely to create unique challenges in developing an automated remote sensing system for ALS modules. The cramped quarters within ALS plant growth units will create problems in collecting spectral reflectance measurements from the nadir position (i.e. directly above plant canopies) and, thus, crop canopies likely will be imaged from a diversity of orientations relative to the primary illumination source. In general, highly reflective white or polished surfaces will be used within an ALS plant growth module to maximize the stray light that is reflected onto plant canopies. Initial work suggested that these highly reflective surfaces might interfere with the collection of spectral reflectance measurements of plants, but the use of simple remote sensing algorithms such as 760/685 band ratios or normalized difference vegetation index (NDVI) images greatly reduced the effects of the reflective backgrounds. A direct comparison of 760/685 and NDVI images from canopies of lettuce, pepper and tomato plants indicated that unique models of individual plants are going to be required to properly assess the health conditions of canopies. A mixed model of all three plant species was not effective in predicting plant stress using either the 760/685 or NDVI remote sensing algorithms.
Who needs the concept of spirituality? Human beings seem to!
Authors: BREITBART WILLIAM
Published: May 2007

Well, it's finally happened. I've been attacked in the
scientific literature (Salander, 2006). Well,
just to clarify, it wasn't a personal attack, but rather an attack of
the highest and most noble order: an attack on the scientific rigor of the
conceptual underpinnings of my recent work on meaning and spirituality in
advanced cancer patients (e.g., Breitbart, 2002). To be honest, and a bit less grandiose, it was
not an attack against me alone, but rather a set of critical comments
aimed at a growing number of investigators who have been publishing papers
(a 600% increase over the past 10 years) dealing with religious or
spiritual aspects of life-threatening illness (Stefanek et al., 2005). The critical comments by Dr. Par Salander of
the Department of Social Welfare, Umea University, Sweden, in a recent
issue of the journal Psycho-oncology (Salander, 2006) challenge the need for and the validity of the
concept of spirituality.
Urban voices: The quality-of-life experience among women of color with breast cancer
Authors: FATONE ANNE M. , MOADEL ALYSON B. , FOLEY FREDERICK W. , FLEMING MEGAN , JANDORF. LINA
Published: May 2007

Objectives:Research on the health-related quality of life (HRQL) among women of color (i.e., Hispanics and African Americans) with breast cancer suggests that they may be at elevated risk for a variety of physical and psychosocial sequelae. The context in which these women perceive, experience, and respond to these HRQL challenges can provide important information for planning a culturally appropriate palliative care treatment plan.

Methods: In an effort to understand the quality of lifeexperienceafter breast cancer among women of color, this study describes the nature and impact of physical, emotional, and menopausal symptoms among African American (n= 8) and Hispanic (n= 12) breast cancer survivors based on qualitative data gathered through semistructured interviews. Themes were identified and categorized into six HRQL domains: physical (e.g., pain, nausea), psychological (e.g., sadness, irritability), cognitive (e.g., memory problems), sexual (e.g., decreased desire), social/functional (e.g., financial strain, social distress), and spiritual/existential (e.g., increased faith, spiritual coping), with high interrater reliability (kappa = .81).

Results:For both groups, physical issues had a major impact on HRQL, with psychological issues being additionally salient for Hispanic women. Most (88%) African American women voiced positive changes in their faith after diagnosis whereas 50% of Hispanic women viewed faith as an important way of coping with breast cancer.

Significance of results:This research broadens our understanding of the experience of breast cancer among ethnic minority women, and in turn, offers some key directions for guiding the development of culturally tailored HRQL interventions.
Unmet needs among adolescent cancer patients: A pilot study
Authors: PALMER SUSAN , MITCHELL ANNE , THOMPSON KATE , SEXTON MAREE
Published: May 2007

Objective:Adolescents with cancer pose a unique challenge to current health systems and the professional working with them. Throughout the world, it is increasingly recognized that the needs of this particular group of patients may not be met through existing services within either the pediatric or adult systems. In Australia, this is a new area of research, and little is known about the unmet physical, psychological, and social needs of this patient group. This study reports the outcomes of a focus group conducted to explore these issues.

Methods:Six young people, with a mean age at diagnosis of 17 years and 6 months, participated in a 2-h focus group. A qualitative analytic approach was utilized to examine themes.

Results:The participants identified a number of concerns relating to three broad categories: information provision, treatment processes, and survivorship.

Significance of results:The research findings support previously documented evidence that indicate gaps in cancer services provided to this age group. Importantly, these gaps can be narrowed by improving access to adolescent multidisciplinary teams and introducing specific training for health care professionals.
Adolescents and young adults with cancer: The challenge
Authors: THOMAS DAVID M.
Published: May 2007

Adolescence and young adulthood is a time of enormous change. For many
young people, the profound shift from dependence to autonomy that is the
hallmark of this period is physically, emotionally, and spiritually
demanding. On the other hand, this phase of life is generally marked by an
exuberant optimism that is the envy of jaded adulthood. This optimism,
when coupled with intelligence, lack of respect for established forms, and
iconoclastic energy, may be the source of a lifetime's
achievement.
Survivors Day
Authors: BUDABIN GEORGE
Published: May 2007

George Budabin is a cancer survivor. What follows are his remarks
commemorating Survivors Day 2006 at New York Presbyterian Hospital in New
York City.
In Summer
Authors: Neimeyer Robert
Published: May 2007

In Summer.
Urtikaria und Parasiten: Fallbericht und Übersicht über die häufigsten parasitären Erreger der chronischen Urtikaria
Authors: Oberholzer  , Nüesch  , Häusermann
Published: May 2007

Die chronische Urtikaria stellt eine relativ häufige poliätiologische Krankheit dar. Bei Vorliegen einer Bluteosinophilie muss differenzialdiagnostisch an eine Parasitose gedacht werden. Bei Urtikariaformen, die assoziiert mit Echinokokkus- und Helminthen-Infektionen auftreten, findet sich eine IgE-vermittelte Histaminfreisetzung. Zudem sind bei diesen und anderen parasitären Infektionen verschiedene Zytokine involviert, die in der Pathogenese der Urtikaria eine Rolle spielen. Die Zahl der publizierten Fallberichte einer durch Amöben induzierten chronischen Urtikaria ist gering. Die Amöbeninfektion erfolgt fäko-oral und der Erreger kann mittels einfachen Stuhluntersuchungen oder mit einer Antigen-Testung und molekularen Methoden nachgewiesen werden. Im vorliegenden Fall konnte eine komplette Remission der chronischen Urtikaria nach Behandlung der Amöbeninfektion mit Flagyl und Humatin erreicht werden, sodass ein direkter Kausalzusammenhang der chronischen Urtikaria angenommen werden darf.
Solute mixing during imbibition and drainage in a macroscopically heterogeneous medium
Authors: Rossi M. , Lehmann P. , Ursino N. , Ippisch O. , Flühler H.
Published: May 2007

We studied the flow of water and the transport of solutes in a heterogeneously packed sand tank by performing transport experiments with a fluorescent tracer. The packing consisted of an inclined, layered sand bedding characterized by a large number of thin layers of three quartz sands of different grain sizes. The purpose was to evaluate to which extent the preceding wetting‐draining history affects the mixing of solutes in presence of textural heterogeneities. We irrigated the surface at stepwise increased flow rates (imbibition) and afterward at stepwise decreased flow rates (drainage). At each step the flow rate was kept constant to monitor the transport and spreading of several tracer plumes in the stationary flow field. The results show that during imbibition, mixing at the textural boundaries is hindered and the solutes are funneled through connected preferential flow paths. During drainage we observed enhanced mixing resulting in a definitely less heterogeneous transport regime. These results stress the role of the preceding wetting‐draining history for determining the characteristics of solute transport in heterogeneous media. We demonstrate this using the integral mixing characteristics “dilution index” and “reactor ratio,” which quantify the degree of preferentiality of flow and transport.
Horizontal displacement of carbon associated with agriculture and its impacts on atmospheric CO2
Authors: Ciais P. , Bousquet P. , Freibauer A. , Naegler T.
Published: May 2007

The growth of crops represents a sink of atmospheric CO2, whereas biomass is consumed by humans and housed animals, yielding respiratory sources of CO2. This process induces a lateral displacement of carbon and creates geographic patterns of CO2 sources and sinks at the surface of the globe. We estimated the global carbon flux harvested in croplands to be 1290 TgC/yr. Most of this carbon is transported into domestic trade, whereas a small fraction (13%) enters into international trade circuits. We then calculated the global patterns of CO2 fluxes associated with food and feedstuff trade, using country‐based agricultural statistics and activity maps of human and housed animal population densities. The CO2 flux maps show regional dipoles of sources and sinks in Asia and North America. The effect of these fluxes on atmospheric CO2 was simulated using a global atmospheric transport model. The mean latitudinal CO2 gradients induced by the displacement of crop products are fairly small (≈0.2 ppm) compared with observations (4–5 ppm), indicating that this process has a only a small influence in explaining the latitudinal distribution of CO2 fluxes. On the other hand, the simulated longitudinal mean atmospheric CO2 gradients at northern midlatitudes (≈ up to 0.5 ppm) are comparable to the ones measured between atmospheric stations, suggesting that CO2 fluxes from crop products trade are an important component of continental‐ and regional‐scale CO2 budgets. Thus they should be accounted for as prior information in regional inversions.
Deep‐dwelling foraminifera as thermocline temperature recorders
Authors: Cléroux Caroline , Cortijo Elsa , Duplessy Jean‐Claude , Zahn Rainer
Published: May 2007

We measured the oxygen isotopic composition of the deep‐dwelling foraminiferal species G. inflata, G. truncatulinoides dextral and sinistral, and P. obliquiloculata in 29 modern core tops raised from the North Atlantic Ocean. We compared calculated isotopic temperatures with atlas temperatures and defined ecological models for each species. G. inflata and G. truncatulinoides live preferentially at the base of the seasonal thermocline. Under temperature stress, i.e., when the base of the seasonal thermocline is warmer than 16°C, G. inflata and G. truncatulinoides live deeper in the main thermocline. P. obliquiloculata inhabits the seasonal thermocline in warm regions. We tested our model using 10 cores along the Mauritanian upwelling and show that the comparison of δ18O variations registered by the surficial species G. ruber and G. bulloides and the deep‐dwelling species G. inflata evidences significant glacial‐interglacial shifts of the Mauritanian upwelling cells.
Circulation rate changes in the eastern subtropical North Pacific based on chlorofluorocarbon ages
Authors: Sonnerup Rolf E. , Bullister John L. , Mecking Sabine
Published: May 2007

A space‐time regression analysis of chlorofluorocarbon (CFC) data from the eastern North Pacific Ocean's subtropical thermocline (25.6–26.6 σθ) is used to extract age and velocity changes from a collection of 1980s and 1990s hydrographic sections. Results indicate substantial increases of CFC ages, from 0.2 yr yr−1 on 25.8 σθ increasing with depth up to 0.4 yr yr−1 on 26.6 σθ, and increases of meridional age gradients, implying a circulation slowdown. Using the regression‐derived spatial and temporal derivatives, an isopycnal balance of advection and diffusion, including the effects of mixing on CFC ages, was applied to estimate changes in flow. Southward velocities at 20°N, 145°W generally decreased by ∼ 0.03 ± 0.02 cm s−1 yr−1 on isopycnals 25.6 to 26.4 σθ during the 1980s and 1990s, consistent with overturning changes from historical hydrographic data and with concurrent increases in AOU. The deeper (26.6 σθ) age increase was consistent with mixing effects.
Constraints on terrestrial gamma ray flash production from satellite observation
Authors: Carlson B. E. , Lehtinen N. G. , Inan U. S.
Published: May 2007

Terrestrial gamma‐ray flash (TGF) production has been modeled by several emission mechanisms. In spite of extensive studies of these mechanisms and the existing satellite data, significant uncertainties exist about the nature of the source. In this paper, we present a method to develop approximate production‐mechanism‐independent constraints on TGF production on the basis of Monte Carlo simulation of gamma‐ray propagation through the atmosphere. A broad range of possible source parameters are simulated, based on assumptions of a simplified source with varying general properties. The results of the simulations are compared with averaged satellite data, from which constraints are derived. Constraints on the basis of photon fluence and spectral shape are presented and indicate a source of 103−105 J at an altitude of 15–20 km. Possible constraints based on the lateral distance between the location of TGF production and the spacecraft nadir point is also discussed.
Transient geotherms in Archean continental lithosphere: New constraints on thickness and heat production of the subcontinental lithospheric mantle
Authors: Michaut C. , Jaupart C. , Bell D. R.
Published: May 2007

Because of its large thickness and thermal relaxation time, Archean lithosphere cannot be in thermal equilibrium with the instantaneous rate of heat production in the lithospheric mantle and heat supplied to its base. Comparison of xenolith (P,T) data with time‐dependent thermal models allows constraints on lithosphere thickness, in situ heat production in the lithospheric mantle and time changes of basal heat flux. In this paper, the lithosphere is defined as the rigid part of the thermal boundary layer where heat transport occurs by conduction only. A Monte Carlo procedure is used to determine the full range of thermal models consistent with xenolith (P,T) arrays from Newlands and Finsch orangeites, Kaapvaal craton, South Africa. These xenolith suites from an early phase of kimberlite magmatism in the Kaapvaal record thermal conditions in unperturbed lithosphere. Together with constraints on surface heat flow and crustal heat production, these data require the lithosphere thickness to be between 200 and 270 km, with most values between 210 and 250 km. Additional constraints, including the condition that lithospheric temperatures have remained below the solidus, estimates of the cooling rate in mantle xenoliths, and the depth extent of seismic anomalies beneath cratons tighten the solution range. Present‐day values of basal heat flow and heat production in the Kaapvaal lithospheric mantle lie between 12–16 mW m−2 and 0–0.02 μW m−3 respectively. At 240‐km depth, lithospheric material undergoes secular cooling at a rate of 40 to 110 K/Ga due solely to in situ radioactive decay. Changes of basal heat flow must be less than 5% per Ga, suggesting that thermal conditions in the underlying mantle have not changed much since the Archean.
Tracking coherent structures in a regional ocean model with wavelet analysis: Application to Cape Basin eddies
Authors: Doglioli A. M. , Blanke B. , Speich S. , Lapeyre G.
Published: May 2007

This study is mainly aimed at proposing objective tools for the identification and tracking of three‐dimensional eddy structures. It is conducted with a high‐resolution numerical model of the ocean region around South Africa, and emphasis is put on Cape Basin anticyclones and cyclones thought to be actively implicated in the Indian‐Atlantic interocean exchange. We settle on wavelet analysis for the decomposition and processing of successive maps of relative vorticity for a simulation run with ° resolution. The identification of three‐dimensional coherent structures comes with the calculation of eddy trajectories and the time evolution of eddy properties. Instantaneous mass transport and momentum of eddies are calculated from the knowledge of instantaneous drift velocities, volumes, and diameters. The success of the regional model and of the analysis technique is assessed through comparisons with equivalent observations.
A numerical study on nutrient sources in the surface layer of the Japan Sea using a coupled physical‐ecosystem model
Authors: Onitsuka Goh , Yanagi Tetsuo , Yoon Jong‐Hwan
Published: May 2007

A nitrogen‐based four‐compartment ecosystem model coupled with a physical model is applied to the Japan Sea. Seasonal variability in ecosystem dynamics simulated by the coupled model is in good agreement with the observations. A set of artificial tracers labeled according to specified regions is introduced to identify nutrient sources in the surface layer of the Japan Sea. The results of the labeled tracer experiment show that one of the large nutrient sources in the southern Japan Sea is located along the east coast of Korea. The upward flux of dissolved inorganic nitrogen along the east coast of Korea and the nitrogen flux through the western channel of the Tsushima/Korea Straits (TKS) sustain high primary productivity in the southwestern Japan Sea. The surface nutrient conditions in the nearshore region along the Japanese coast depend on the nitrogen flux through the eastern channel of the TKS throughout the year. Since materials transported through the TKS have significant impact on the biological productivity of the southern Japan Sea, field observations of chemical and biological data, in addition to physical ones, should be continued in the TKS.
Source characterization of biomass burning particles: The combustion of selected European conifers, African hardwood, savanna grass, and German and Indonesian peat
Authors: Iinuma Y. , Brüggemann E. , Gnauk T. , Müller K. , Andreae M. O. , Helas G. , Parmar R. , Herrmann H.
Published: May 2007

We carried out a detailed size‐resolved chemical characterization of particle emissions from the combustion of European conifer species, savanna grass, African hardwood, and German and Indonesian peat. Combustion particles were sampled using two sets of five‐stage Berner‐type cascade impactors after a buffer volume and a dilution tunnel. We determined the emission factors of water‐soluble organic carbon (WSOC, 46–6700 mg kg−1, sum of five stages), water‐insoluble organic carbon (WISOC, 1300–6100 mg kg−1), (apparent) elemental carbon (ECa, 490–1800 mg kg−1), inorganic ions (68–400 mg kg−1), n‐alkanes (0.38–910 mg kg−1), n‐alkenes (0.45–180 mg kg−1), polycyclic aromatic hydrocarbons (PAHs) (1.4–28 mg kg−1), oxy‐PAHs (0.08‐1.0 mg kg−1), lignin decomposition products (59–620 mg kg−1), nitrophenols (1.4–31 mg kg−1), resin acids (0–110 mg kg−1), and cellulose and hemicellulose decomposition products (540–5900 mg kg−1). The combustion and particle emission characteristics of both of peat were significantly different from those of the other biofuels. Peat burning yielded significantly higher emission factors of total fine particles in comparison to the other biofuels. Very high emission factors of n‐alkanes and n‐alkenes were observed from peat combustion, which may be connected to the concurrently observed “missing” CCN in peat smoke. A high level of monosaccharide anhydrides, especially levoglucosan, was detected from all types of biofuel combustion. The fractions of monosaccharide anhydrides in the emitted total carbon were higher in smaller particles (aerodynamic diameter, Dpa < 0.42 μm).
Southern Hemisphere midlatitude atmospheric variability of the NCEP‐NCAR and ECMWF reanalyses
Authors: Dell'Aquila Alessandro , Ruti Paolo M. , Calmanti Sandro , Lucarini Valerio
Published: May 2007

We compare the representation of the Southern Hemisphere midlatitude winter variability in the NCEP‐NCAR and ERA40 reanalyses by using the Hayashi spectral technique. We find important discrepancies in the description of the atmospheric waves at different spatial and temporal scales. ERA40 is generally characterized by a larger variance, especially in the high‐frequency spectral region. Compared to the Northern Hemisphere, the assimilated data are relatively scarce particularly over the oceans, and they provide a weak constraint to the assimilation system even in the period when satellite data are available. In the presatellite period the discrepancies between the two reanalyses are large and randomly distributed; after 1979 the discrepancies are systematic. This study suggests that, as for the winter midlatitude variability in the Southern Hemisphere, a well‐defined picture to be used in the evaluation of climate model simulations is still lacking because of the nonconsistency of the reanalyses.
Influence of lateral and top boundary conditions on regional air quality prediction: A multiscale study coupling regional and global chemical transport models
Authors: Tang Youhua , Carmichael Gregory R. , Thongboonchoo Narisara , Chai Tianfeng , Horowitz Larry W. , Pierce Robert B. , Al‐Saadi Jassim A. , Pfister Gabriele , Vukovich Jeffrey M. , Avery Melody A. , Sachse Glen W. , Ryerson Thomas B. , Holloway John S. , Atlas Elliot L. , Flocke Frank M. , Weber Rodney J. , Huey L. Gregory , Dibb Jack E. , Streets David G. , Brune William H.
Published: May 2007

The sensitivity of regional air quality model to various lateral and top boundary conditions is studied at 2 scales: a 60 km domain covering the whole USA and a 12 km domain over northeastern USA. Three global models (MOZART‐NCAR, MOZART‐GFDL and RAQMS) are used to drive the STEM‐2K3 regional model with time‐varied lateral and top boundary conditions (BCs). The regional simulations with different global BCs are examined using ICARTT aircraft measurements performed in the summer of 2004, and the simulations are shown to be sensitive to the boundary conditions from the global models, especially for relatively long‐lived species, like CO and O3. Differences in the mean CO concentrations from three different global‐model boundary conditions are as large as 40 ppbv, and the effects of the BCs on CO are shown to be important throughout the troposphere, even near surface. Top boundary conditions show strong effect on O3 predictions above 4 km. Over certain model grids, the model's sensitivity to BCs is found to depend not only on the distance from the domain's top and lateral boundaries, downwind/upwind situation, but also on regional emissions and species properties. The near‐surface prediction over polluted area is usually not as sensitive to the variation of BCs, but to the magnitude of their background concentrations. We also test the sensitivity of model to temporal and spatial variations of the BCs by comparing the simulations with time‐varied BCs to the corresponding simulations with time‐mean and profile BCs. Removing the time variation of BCs leads to a significant bias on the variation prediction and sometime causes the bias in predicted mean values. The effect of model resolution on the BC sensitivity is also studied.
Forest fire plumes over the North Atlantic: p‐TOMCAT model simulations with aircraft and satellite measurements from the ITOP/ICARTT campaign
Authors: Cook Peter A. , Savage Nicholas H. , Turquety Solène , Carver Glenn D. , O'Connor Fiona M. , Heckel Andreas , Stewart David , Whalley Lisa K. , Parker Alex E. , Schlager Hans , Singh Hanwant B. , Avery Melody A. , Sachse Glen W. , Brune William , Richter Andreas , Burrows John P. , Purvis Ruth , Lewis Alastair C. , Reeves Claire E. , Monks Paul S. , Levine James G. , Pyle John A.
Published: May 2007

Intercontinental Transport of Ozone and Precursors (ITOP) (part of International Consortium for Atmospheric Research on Transport and Transformation (ICARTT)) was an intense research effort to measure long‐range transport of pollution across the North Atlantic and its impact on O3 production. During the aircraft campaign plumes were encountered containing large concentrations of CO plus other tracers and aerosols from forest fires in Alaska and Canada. A chemical transport model, p‐TOMCAT, and new biomass burning emissions inventories are used to study the emissions long‐range transport and their impact on the troposphere O3 budget. The fire plume structure is modeled well over long distances until it encounters convection over Europe. The CO values within the simulated plumes closely match aircraft measurements near North America and over the Atlantic and have good agreement with MOPITT CO data. O3 and NOx values were initially too great in the model plumes. However, by including additional vertical mixing of O3 above the fires, and using a lower NO2/CO emission ratio (0.008) for boreal fires, O3 concentrations are reduced closer to aircraft measurements, with NO2 closer to SCIAMACHY data. Too little PAN is produced within the simulated plumes, and our VOC scheme's simplicity may be another reason for O3 and NOx model‐data discrepancies. In the p‐TOMCAT simulations the fire emissions lead to increased tropospheric O3 over North America, the north Atlantic and western Europe from photochemical production and transport. The increased O3 over the Northern Hemisphere in the simulations reaches a peak in July 2004 in the range 2.0 to 6.2 Tg over a baseline of about 150 Tg.
Stable isotopic variations in west China: A consideration of moisture sources
Authors: Tian Lide , Yao Tandong , MacClune K. , White J. W. C. , Schilla A. , Vaughn B. , Vachon R. , Ichiyanagi K.
Published: May 2007

In this study, individual precipitation samples, collected over 2 years at stations in different climatic regions of west China (Tibetan Plateau region, Tianshan region, and Altay) were analyzed for the stable isotopes of precipitation to improve our understanding of how vapor transport impacts the modern stable isotopic distribution. Our results identify regional patterns in both δ18O and deuterium excess (D excess, defined as δD – 8δ18O), and in particular we have identified the northward maximum extent of the southwest monsoon over the Tibetan Plateau. This demarcation is also the boundary for the fractionation effect of temperature on stable isotopes in precipitation. The patterns we have identified are as follows: (1) In the southern Tibetan Plateau, along the southern slope of the Himalayas, our results show a distinct seasonality for both δ18O and D excess as a result of the shift of summer monsoon moisture and winter westerly moisture transport. The signals of δ18O in the western Tibetan Plateau reveal that the region receives southwest monsoonal moisture. In the east of the plateau, stable isotopic variation shows alternation between monsoon intrusion and recycling of northern moisture. (2) In contrast, in Tianshan there is an apparent “temperature effect” in δ18O, with enriched values occurring in summer and depleted values occurring in winter. Seasonal D excess values, opposite to those observed in the southern Tibetan Plateau, are controlled by differing seasonal evaporation conditions. (3) In Altay, the most northern mountain region, the seasonal δ18O shows the same variation with that in Tianshan region. However, D excess shows no apparent seasonal variation.
Multilayered cloud parameters retrievals from combined infrared and microwave satellite observations
Authors: Romano F. , Cimini D. , Rizzi R. , Cuomo V.
Published: May 2007

A technique based on multispectral satellite observations is proposed to improve the retrieval of cloud parameters in presence of scenes with overlapping cloud layers. The technique combines satellite data measured by the Atmospheric Infrared Radiation Sounder, the Advanced Microwave Sounding Unit‐A/B, and the Moderate Resolution Imaging Spectrometer. Cloud properties, such as top heights (CTH) and base heights (CBH), integrated water vapor (IWV), liquid water path (LWP), and ice water path (IWP), are estimated for a variety of scenes, including multilayered cloud cases. Satellite retrievals are validated against ground‐based observations collected at the Chilbolton Observatory Facilities (UK) during spacecraft overpasses. Results from the proposed technique are compared with retrievals using the CO2 slicing method (CTH only) and the standard AIRS Level 2 products (CTH, IWV, and LWP). The proposed technique shows significant improvements, especially in the presence of multiple cloud layers, at the expenses of larger computational efforts. For the data set considered in this study (40 cases), the root mean squared agreement with ground‐based observations is within 295, 905, 1094, and 1862 m for the first two CTH and CBH, respectively, and 0.62, 0.08, and 0.02 kg/m2 for IWV, LWP, and IWP, respectively.
Sensitivity of the shortwave radiative budget to the parameterization of ice crystal effective radius
Authors: van Zadelhoff G.‐J. , van Meijgaard E. , Donovan D. P. , Knap W. H. , Boers R.
Published: May 2007

A new effective particle size (Reff) parameterization for ice clouds has been formulated based on depth into cloud relative to cloud top. This parameterization has been developed based on an extensive data set of lidar and radar ice cloud retrievals. Using this parameterization within the stand‐alone radiation code from the European Centre for Medium Range Weather Forecasting (cy23r4), the performance of the new parameterization is compared with the more commonly used parameterizations based on temperature and/or ice water content. An evaluation is performed on the basis of observed shortwave fluxes for 13 days with persistent ice cloud decks, with no liquid clouds beneath, over the Cabauw Experimental Site for Atmospheric Research in the Netherlands. For each of these clouds the shortwave flux is calculated after which the distribution of the differences between the observed and modeled shortwave fluxes from the combined 13 days are compared with each other. The new parameterization shows a median absolute difference of 0.7 W m−2 relative to the observations. The control parameterization based on temperature shows a median absolute difference of 15 W m−2. Within the framework of the KNMI regional climate model (RACMO2), the new parameterization yields an effective particle size versus temperature distribution very similar to the observed distributions from lidar and radar retrievals. Results from a 1‐year integration indicate that the domain averaged monthly mean planetary albedo and transmissivity change by a maximum of 2.6 and 2.4%, respectively, using the new parameterization compared to the temperature‐based parameterization.
High‐resolution ensemble surface insolation estimates through assimilation of coarse‐scale retrievals into a simple physical model: 1. Physical model development and accuracy tests
Authors: Lee Songweon , Margulis Steven A.
Published: May 2007

A simple physical radiative transfer insolation model (mG‐model) is developed for use in both prediction (part 1) and data assimilation applications (part 2). The primary novel aspect of the model is the use of the Visible Infrared Solar‐infrared Split window Technique (VISST) pixel‐level cloud product. The parsimony of the model and high‐resolution VISST cloud product allows for the computationally efficient prediction of high‐resolution solar radiation fields. The mG‐model, which has 0.02° spatial and half‐hourly temporal resolutions, was tested over the Southern Great Plains during the summer of 1997 and compared to measurements from the Atmospheric Radiation Measurement (ARM) project and the Global Energy Water Exchange (GEWEX) Continental Scale International Project and GEWEX Americas Prediction Project (GCIP/GAPP) Shortwave Radiation Budget (SRB) product. When investigating the insolation accuracy conditioned on cloud fraction, the mG‐model and the SRB data showed similar accuracy under clear and partly cloudy‐sky conditions. However, there are better results in the coarser SRB product under cloudy‐sky conditions, which makes the general performance of the SRB product better than that of the mG‐model. This result is the primary motivation for employing a data assimilation scheme to assimilate the SRB data into the mG‐model, which would combine the benefits of the mG‐model (higher resolution) and the SRB insolation product (resulting from a more complicated physical retrieval model) and provide dynamic error bound estimates that are reflective of input uncertainty. This data assimilation approach is described in part 2.
Impacts of biogenic emissions on photochemical ozone production in Houston, Texas
Authors: Li Guohui , Zhang Renyi , Fan Jiwen , Tie Xuexi
Published: May 2007

A regional chemical transport model (CTM) has been employed to assess the influence of biogenic emissions on ozone (O3) formation in Houston, Texas during an eight‐day episode of 24–31 August 2000 in association with the Texas Air Quality Study (TexAQS) 2000. The effects of isoprene and monoterpene emissions on O3 photochemistry in this region were investigated. Isoprene emissions played an important role in O3 formation when the O3 plume occurred in the afternoon over the urban Houston area. When the isoprene emissions were decreased or increased by 50%, the O3 concentration was decreased or increased by 5–25 ppb over the urban Houston area, respectively, but the change in the O3 concentration was less than 5–10 ppb over the industrial Ship Channel. Additional sensitivity studies showed that the surface O3 change resulted primarily from local isoprene emissions, although transport of isoprene from the north of the urban Houston area was found to be nonnegligible in the isoprene budget on several days. The contribution of monoterpene emissions to O3 formation was insignificant due to low emission rate and relatively slow reaction rate.
Retrieval of tropospheric ozone: The synergistic use of thermal infrared emission and ultraviolet reflectivity measurements from space
Authors: Landgraf J. , Hasekamp O. P.
Published: May 2007

We investigate the synergistic use of ultraviolet reflectivity measurements in the spectral range of 290–320 nm and the thermal emission spectra at the 9.6‐μm ozone absorption band for the retrieval of vertical distribution of tropospheric ozone from satellite observations. Retrievals of vertical ozone profiles are performed from simulated measurements for different atmospheric conditions. The retrievals show that the use of measurements of both spectral ranges can improve significantly the retrieved ozone in the lowest 5 km of the troposphere. Here largest improvements are found for tropical temperature distributions and for a low thermal contrast in the lower troposphere. So the use of both spectral bands may help to improve the remote sensing of tropospheric ozone from space.
Coronae of Parga Chasma, Venus
Authors: Martin P. , Stofan E. R. , Glaze L. S. , Smrekar S.
Published: May 2007

Parga Chasma is a 10,000 km long fracture and trough system in the southern hemisphere of Venus. In this study, we analyze coronae in the Parga region, addressing the relationship between corona and rift formation, the relationship of volcanism to rifting and coronae, and the overall evolution of the rift system. Our observations are compared with various models, with the aim of determining any causative relationships between corona formation, volcanism, and rifting. Our statistical analysis shows that coronae are randomly located within this region, indicating that corona locations are not significantly controlled by rifting, or by lithospheric loading caused by the earlier formation of other coronae. Our observations suggest that the two processes of corona and rift formation were occurring more or less synchronously, with no specific control on each other, but that coronae and rifting in this region are genetically related. We find a wide variation in the amount of volcanism associated with coronae across the Parga region, and no evidence for a deep‐seated plume or multiple plumes beneath Parga Chasma. We suggest that the concentration of volcanic features in the Beta‐Atla‐Themis region may actually result from three independent but overlapping broad zones of deformation, corona formation, and enhanced volcanism associated with the three rifts (Parga, Hecate, and Devana Chasmata), rather than one large zone of activity covering the whole of the region simultaneously.
Meander geometry of Venusian canali: Constraints on flow regime and formation time
Authors: Bray V. J. , Bussey D. B. J. , Ghail R. C. , Jones A. P. , Pickering K. T.
Published: May 2007

The similar meander geometries of Venusian canali and terrestrial rivers imply that the in‐channel flow regimes may be comparable. This work details meander geometry measurements from ten lowland canali and compares the extensive data set produced to a variety of solar system channels. The meander properties of Venusian canali do not closely match any channel so far observed on the terrestrial planets. However, analysis of the relationship between meander wavelength and radius of channel curvature confirms previous suggestions that the canali were carved by a low (water‐like) viscosity fluid. Whether the canali are due to thermal and/or mechanical erosion of the plains by an exotic lava, or have some other genesis, the dominant meander wavelengths of 11 to 77 km require peak fluid discharge rates of up to 6.6 × 106 m3 s−1, an order of magnitude larger than terrestrial rivers. Slight decrease in width along the channel length was observed in most investigated canali, perhaps reflecting the effect of downstream loss processes. Cyclical variations in the average channel width were observed in some channels; where topographic data are available, these variations apparently correlate with peaks in plains topography. This indicates that the canali remained active, after their initially rapid formation, long enough to interact with the early stages of plains tectonism.
The chemical composition of the early terrestrial atmosphere: Formation of a reducing atmosphere from CI‐like material
Authors: Hashimoto George L. , Abe Yutaka , Sugita Seiji
Published: May 2007

The chemical composition of Earth's early atmosphere is likely to have played an important role in the origin of life. In particular, the redox state of Earth's early atmosphere may have controlled greatly the efficiency of abiotic synthesis of biologically important organic compounds. However, the chemical composition of the Earth's early atmosphere has not been studied extensively before. In this study, we theoretically estimate the chemical composition of an atmosphere near the end of the completion of planetesimal accretion of the Earth. Our calculation results show that the Earth's early atmosphere is very reducing, rich in H2and/or CH4, regardless of which meteoritic materials accrete and regardless of which chemical reactions control the molecular abundance in the atmosphere. In other words, impact‐degassed origin of Earth's atmosphere leads inevitably to a reducing chemical composition, which is very favorable to efficient prebiotic synthesis of organic matter on Earth.
Structural characteristics and behavior of fire‐modified soil aggregates
Authors: Blake William H. , Droppo Ian G. , Humphreys Geoffrey S. , Doerr Stefan H. , Shakesby Richard A. , Wallbrink Peter J.
Published: May 2007

The transport dynamics of burnt material in fluvial systems require attention since the off‐site transfer of soil material from wildfire‐affected slopes includes ash and nutrients which may have negative impacts on downstream water quality. The aim of this work is to explore the presence, structural characteristics, and fluvial behavior of fire‐modified soil aggregates in burnt soil material sampled from a water supply catchment near Sydney, Australia, and to compare their fluvial behavior to that of composite particles from unburnt soils. Samples of burnt and unburnt soil material were analyzed for effective particle size, settling velocity, composite particle density, and porosity using established microscope‐based image analysis approaches. Burnt soil aggregates exhibit significantly higher settling velocities (mean 11.47 ± 1.11 mm s−1) than unburnt particles of similar diameter (3.36 ± 0.91 mm s−1) reflecting an increase in density because of reduction in organic content and a reduction in pore space linked to shrinkage. Soil aggregates in severely burnt soil are dense and inorganic and behave differently to their unburnt counterparts and discrete grains of the same size. Burnt composite particles are robust and readily transported within fluvial systems. Their presence in burnt soil and mobilized material is likely to have important implications for postfire fine (<63 μm) sediment and nutrient budgets.