bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence, severity, and chronicity of pain and general health‐related quality of life in patients with localized prostate cancer
Authors: Gerbershagen Hans J. , Özgür Enver , Straub Karin , Dagtekin Oguzhan , Gerbershagen Kathrin , Petzke Frank , Heidenreich Axel , Lehmann Klaus A. , Sabatowski Rainer
Published: September 2007

Aims: To analyze the prevalence and the severity spectrum of pain and its relationships to health‐related quality of life and the bio‐psycho‐social consequences of pain among patients scheduled for radical prostatectomy.

Methods: Urological inpatients completed an epidemiological pain questionnaire extensively exploring pre‐operative acute and chronic pains in 21 body regions. The severity of pain was determined using von Korff's Pain Grading (CPGQ). Pain chronicity was estimated employing the Mainz Pain Staging System (MPSS). Anxiety and depressive symptoms were identified with the HADS and the Habitual Well‐Being Questionnaire (FW‐7). Health‐related quality of life was measured using the SF‐12. Comorbidities and comorbidity‐related interferences with daily activities were ascertained with the Weighted Illness Checklist (WICL).

Results: Eighty of 115 patients (69.6%) reported about pain during the last 3 months pre‐operatively. 28.7% of the pain patients had pain related to urological disease. Severe dysfunctional pain was identified by pain Grades 3 and 4 of the CPGQ in 20% and 13.8%, respectively. Advanced pain chronicity characterized by pain Stages II and III of the MPSS was present in 38.8% and 11.3%. Patients with localized prostate cancer without pain complaints had significantly better health‐related quality of life and habitual well‐being and lower anxiety and depression scores and fewer comorbidities. Patients with cancer‐related and non‐cancer pain did not differ in pain chronicity, pain severity, pain intensities, anxiety, comorbidities and physical health (SF12‐PCS).

Conclusions: The high prevalence of severe and chronic pain in cancer patients before scheduled radical prostatectomy – combined with considerable disability effects and markedly reduced quality of life necessitate a short routine screening‐analysis of the severity spectrum of pain and psychopathology. Patient self‐rated pain chronicity staging and psychological distress analysis will allow a disorder severity‐guided treatment and the prevention of suffering and additional new chronic post‐surgical pain.
A neuronal cell‐based botulinum neurotoxin assay for highly sensitive and specific detection of neutralizing serum antibodies
Authors: Pellett Sabine , Tepp William H. , Clancy Colin M. , Borodic Gary E. , Johnson Eric A.
Published: September 2007

Clostridium botulinum neurotoxin (BoNT) serotypes A and B are widely used as pharmaceuticals to treat various neurological disorders and in cosmetic applications. The major adverse effect of these treatments has been resistance to treatment after multiple injections. Currently, patients receiving BoNT therapies and patients enrolled in clinical trials for new applications and/or new formulations of BoNTs are not routinely monitored for the formation of neutralizing antibodies, since no assay other than the mouse protection procedure is commercially available that reliably tests for the presence of such antibodies. This report presents a highly sensitive and specific neuronal cell‐based assay that provides sensitive and specific detection of neutralizing antibodies to BoNT/A.
Active site closure facilitates juxtaposition of reactant atoms for initiation of catalysis by human dUTPase
Authors: Varga Balázs , Barabás Orsolya , Kovári Júlia , Tóth Judit , Hunyadi-Gulyás Éva , Klement Éva , Medzihradszky Katalin F. , Tölgyesi Ferenc , Fidy Judit , Vértessy Beáta G.
Published: September 2007

Human dUTPase, essential for DNA integrity, is an important survival factor for cancer cells. We determined the crystal structure of the enzyme:α,β‐imino‐dUTP:Mg complex and performed equilibrium binding experiments in solution. Ordering of the C‐terminus upon the active site induces close juxtaposition of the incoming nucleophile attacker water oxygen and the α‐phosphorus of the substrate, decreasing their distance below the van der Waals limit. Complex interactions of the C‐terminus with both substrate and product were observed via a specifically designed tryptophan sensor, suitable for further detailed kinetic and ligand binding studies. Results explain the key functional role of the C‐terminus.
Owners ‘perception of their cats’ quality of life during COP chemotherapy for lymphoma
Authors: Tzannes Sophia , Hammond Margaret F. , Murphy Suzanne , Sparkes Andrew , Blackwood Laura
Published: September 2007

Questionnaires regarding the perceptions of chemotherapy and its impact on the quality of life (QoL) of their cat were received from owners of 31 cats treated for lymphoma between 2002 and 2006 with COP (cyclophosphamide, vincristine, prednisolone) chemotherapy. The QoL scores prior to the onset of cancer (mean 9.5, range 6–10) were significantly higher than the ratings given after the onset of cancer but before commencement of chemotherapy (mean 3.9, range 1–9.4). The QoL scores during chemotherapy (mean 6.3, range 1–10) were also significantly lower than prior to the onset of cancer, but significantly higher during treatment than prior to starting treatment. Adverse effects were experienced by 27 (87%) cats during the course of chemotherapy. Twenty-five (83%) of clients were happy they treated their cat and 27 owners (87%) would treat another cat. The results suggest that COP chemotherapy is perceived by owners to be tolerated by cats.
The responses of serum transferrin receptors to iron supplements in subjects with iron-deficiency erythropoiesis and iron-deficiency anaemia
Authors: Lin Xiao-Ming , Tian Wei , Ma Le , Long Zhu , Zhang Juan , Shen Xiao-Yi , Zhang Xiao-Peng
Published: September 2007

We aimed to study the response of serum transferrin receptors (sTfR) to Fe supplementation in women of childbearing age with Fe-deficiency erythropoiesis (IDE) and Fe-deficiency anaemia (IDA). Primary screening was performed in 942 women ranging in age from 18 to 45 years. After Fe-related biochemical indices such as serum ferritin, Zn protoporphyrin and Hb were determined, the subjects were divided into four groups: normal, Fe store depletion, IDE and IDA. A total of 131 women were randomly selected from the normal, IDE and IDA groups. Subsequently, seventy-six women with IDE and IDA were given various doses of Fe (14 mg/d for IDE; 28 mg/d for IDA) with ferrousl-threonate capsules for twelve consecutive weeks. After receiving Fe supplements, the levels of Fe and sTfR were determined at weeks 0, 3, 6, 9 and 12.The levels of sTfR in women of childbearing age with IDE and IDA were significantly higher than those in the normal group. After receiving Fe supplements, the levels of sTfR were significantly decreased in women of childbearing age with IDE and IDA, while the levels of serum ferritin were significantly increased. In conclusion, STfR can be used as a reliable indicator for assessing the efficacy of Fe supplements.
Effect of the LoBAG30 diet on blood glucose control in people with type 2 diabetes
Authors: Nuttall Frank Q. , Schweim Kelly , Hoover Heidi , Gannon Mary C.
Published: September 2007

In subjects with untreated type 2 diabetes, we previously determined that a weight-maintenance, non-ketogenic diet containing 30 % protein, 50 % fat and 20 % carbohydrate (30:50:20) decreased the percentage total glycohaemoglobin (%tGHb) by 2·2 % glycohaemoglobin over 5 weeks compared to a diet recommended for the American public (protein–fat–carbohydrate 15:30:55). Both the fasting and postprandial glucose were decreased. The objective of the present study was to determine if increasing the carbohydrate content from 20 to 30 % at the expense of fat would still provide a similar effect on %tGHb, fasting and postprandial glucose concentration. Eight men with untreated type 2 diabetes were studied over a 5-week period. Results at the beginning (standard diet) and end of the 5-week study were analysed. Body weight was stable. Fasting glucose concentration decreased by 40 %; 24 h glucose area response decreased by 45 %. Insulin did not change. Mean %tGHb decreased by 1·7 (from 10·8 to 9·1 %), and was still decreasing linearly at 5 weeks. In conclusion, a high-protein, 30 % carbohydrate diet could be a patient-empowering method of improving the hyperglycaemia of type 2 diabetes without pharmacologic intervention. Long-term effects and general applicability of this diet remain to be determined.
Effect of prebiotic supplementation on a probiotic bacteria mixture: comparison between a rat model and clinical trials
Authors: Tiihonen Kirsti , Suomalainen Tarja , Tynkkynen Soile , Rautonen Nina
Published: September 2007

The effects of a probiotic mixture (PRO), supplemented with either galacto-oligosaccharide (GOS) or polydextrose (PDX), on cell numbers of lactic acid bacteria (LAB) and bifidobacteria (BIF) were studied in conventional rats and healthy human subjects. In rats the baseline BIF cell numbers were below the detection limit and were increased by the 2-week GOSPRO intervention. In contrast baseline LAB numbers in rats were high and not affected by the treatments. The human study consisted of two independent but concurrent trials; both started with PRO followed by GOSPRO or PDXPRO periods. In the human subjects variation in numbers of BIF and LAB were high. The GOSPRO group exhibited high counts of faecal LAB and BIF at the start and showed little or no effects of the interventions. In contrast, the PDX group had low faecal LAB and BIF numbers at the start and clearly increased cell numbers of BIF after the PDXPRO period, and LAB after the PRO and PDXPRO period, compared with the run-in period. We propose here that responses to pro- and prebiotics are dependent on baseline numbers of LAB and/or BIF, and that the conventional rat model does not predict well the treatment responses in humans. The survival of PRO was presumably enhanced by the use of prebiotic supplementation and advocates the use of particular combinations of pro- and prebiotics.
The ontogeny and systematics of the otarionine trilobiteOtarionellafrom the Devonian of the Montagne Noire, France and the Maider, Morocco
Authors: LEROSEY-AUBRIL RUDY , FEIST RAIMUND , CHATTERTON BRIAN D. E.
Published: September 2007

A new otarionine trilobiteOtarionella rastrumsp. nov., from the late Emsian Mont Peyroux Formation (Montagne Noire, France), is described. Silicified remains, recovered from the underlying Bissounel Formation (early to late Emsian), are also attributed to this new species. These isolated silicified sclerites represent metaprotaspid to young holaspid growth stages, which enables the almost complete ontogeny of an otarionine trilobite with a spinose adult morphology to be described for the first time. Comparison with associated larval and juvenile growth stages ofCyphaspisreveal that the pattern of juvenile cranidial spine distribution inOtarionella rastrumsp. nov. differs from all patterns described so far in the Otarioninae, in particular that characterizing the tribe Otarionini. A second species,Otarionella lkomaliisp. nov., known only from a complete articulated specimen discovered in the early Eifelian of southern Morocco, is also described. Like the middle EifelianOtarionella chamaeleo(Basse, 1997), this new species has only ten thoracic segments, with the fourth and the sixth segments each bearing a long axial spine. In the light of the new elements provided by the ontogenetic sequence ofO. rastrumsp. nov. and the adult specimens of this species andO. lkomaliisp. nov., the putative synonymy ofOtarionellaandOtarionis rejected and a restricted concept of the genusOtarionellais defined.
RAPID FERTILITY DECLINE IN IRAN: ANALYSIS OF INTERMEDIATE VARIABLES
Authors: ERFANI AMIR , MCQUILLAN KEVIN
Published: September 2007

The remarkable decline in fertility in Iran, which saw the total fertility rate fall from 7 children per woman in 1986 to 2 in 2000, has received only limited analysis in the demographic literature. Using the 2000 Iran Demographic and Health Survey and Bongaarts’ age-specific fertility model, this paper examines the role of the major proximate determinants of fertility in bringing about the rapid decrease in fertility in Iran. The analysis indicates that contraception had the largest effect on fertility, accounting for 61% of the reduction in fertility from its theoretical maximum. The fertility-inhibiting effect of marriage patterns accounted for an additional 31% reduction, and was most important among the young. Further analysis of contraceptive behaviour suggests that the current period fertility rate of 2·0 children per woman is an outcome of a synchronization of delaying and spacing of births among younger women with stopping of childbearing among women in the middle and late reproductive ages. The policy implications of the results are discussed.
Vertigo, dizziness and imbalance in the elderly
Authors: Üneri A , Polat S
Published: September 2007

Objective:

The aim of this retrospective analysis was to evaluate the diagnosis of vertigo, dizziness and imbalance in elderly patients in two tertiary neurotology clinics.

Design and setting:

Six hundred and seventy-seven patients aged over 65 years were assessed by the same senior author, and 601 patients were enrolled in the study.

Results:

The most frequent diagnoses were benign paroxysmal positional vertigo (42.43 per cent), idiopathic vestibulopathy (20.29 per cent), migraine vestibulopathy (13.15 per cent), Ménière's disease (12.47 per cent) and acute vestibular attack (6.49 per cent).

Conclusion and significance:

This retrospective study showed that 93.5 per cent of the elderly patients studied had been diagnosed with peripheral vertigo. The majority of patients had been classified as having benign paroxysmal positional vertigo, idiopathic vestibulopathy or migraine vestibulopathy.
What causes the sporadic phytoplankton bloom southeast of Madagascar?
Authors: Uz B. Mete
Published: September 2007

A large, dendritic phytoplankton bloom develops in the austral summer of roughly every other year in the Indian Ocean southeast of Madagascar. It starts in February or March and dissipates by the end of April. It was observed in 1997, 1999, 2000, 2002, and 2004 and was absent in 1998, 2001, 2003, and 2005. A. Longhurst, who described it in 2001, suggested that the bloom is caused by the entrainment of nutrient‐rich waters into a deepening mixed layer. At the time the bloom had been seen to fail only once, in 1998, and Longhurst attributed that to reduced entrainment due to low winds during the strong La Niña. Since reanalysis winds are not correlated with the occurrence/failure of the bloom, and since the bloom starts before sea surface temperature (SST) peaks and increased chlorophyll is found with high rather than low SST, entrainment is an unlikely cause. Argo float profiles from 2004 show the bloom within a shallow mixed layer over a very strong pycnocline. This indicates that the bloom is caused not by entrainment of nutrient‐rich waters from below, but by another mechanism such as nitrogen fixation by diazotrophs that are retained within a shallow, well‐lit layer, or nutrient fluxes due to vertically mobile plankton. This bloom is among the strongest features of interannual variability in the ocean color time series, second only to El Niño–Southern Oscillation (ENSO)‐related variability in terms of both the area effected and magnitude of the anomaly. While the mechanisms with which biology responds to the physical changes associated with ENSO are well‐known and rather obvious in the strong correlations with physical indicators such as sea surface height or temperature, the occurrence/failure of a strong Madagascar bloom does not have an obvious correlation with any physical parameter. Of the many variables tested, only the landfall of tropical cyclones on the island of Madagascar correlated with the occurrence of the bloom. A hypothesis is presented, without any proof other than that it explains the location, seasonal timing, interannual variability, and observations of temperature and mixed layer depth, on the basis of the premise that runoff from the island alleviates iron limitation of diazotrophs. Definitive determination of the nature of the bloom will probably require in situ sampling.
Characteristics of global and regional drought, 1950–2000: Analysis of soil moisture data from off‐line simulation of the terrestrial hydrologic cycle
Authors: Sheffield Justin , Wood Eric F.
Published: September 2007

Drought occurrence is analyzed over global land areas for 1950‐2000 using soil moisture data from a simulation of the terrestrial water cycle with the Variable Infiltration Capacity (VIC) land surface model, which is forced by an observation based meteorological data set. A monthly drought index based on percentile soil moisture values relative to the 50‐year climatology is analyzed in terms of duration, intensity and severity at global and regional scales. Short‐term droughts (<= 6 months) are prevalent in the Tropics and midlatitudes, where inter‐annual climate variability is highest. Medium term droughts (7–12 months) are more frequent in mid‐ to high‐latitudes. Long term (12+ months) droughts are generally restricted to sub‐Saharan Africa and higher northern latitudes. The Sahel region stands out for having experienced long‐term and severe drought conditions. Severe regional drought events are systematically identified in terms of spatial coverage, based on different thresholds of duration and intensity. For example, in northern Europe, 1996 and 1975 were the years of most extensive 3‐ and 12‐month duration drought, respectively. In northern Asia, severe drought events are characterized by persistent soil moisture anomalies over the wintertime. The drought index identifies several well‐known events, including the 1988 US, 1982/83 Australian, 1983/4 Sahel and 1965/66 Indian droughts which are generally ranked as the severest and most spatially extensive in the record. Comparison with the PDSI shows general agreement at global scales and for these major events but they diverge considerably in cooler regions and seasons, and especially in latter years when the PDSI shows a larger drying trend.
Water sources in semiarid northeast Asia as revealed by field observations and isotope transport model
Authors: Sato Tomonori , Tsujimura Maki , Yamanaka Tsutomu , Iwasaki Hiroyuki , Sugimoto Atsuko , Sugita Michiaki , Kimura Fujio , Davaa Gombo , Oyunbaatar Dambaravjaa
Published: September 2007

Origin of water vapor, which falls as precipitation over arid/semiarid area in northeast Asia, is investigated by modeling and observational approaches. The regional climate model evaluates the spatiotemporal variations of precipitation and water vapor budget, which are used to drive the single‐layer isotope circulation model. Intraseasonal variations of δ18O in precipitation are well simulated during June‐July‐August of 2003. The δ18O in water vapor experiences rapid decreases according to the passage of synoptic‐scale disturbances. The rapid decreases of δ18O are attributed to two processes. (1) The δ18O in air mass locally decreases over the western mountains associated with the mountain precipitation; the light vapor is advected to eastern Mongolia by the prevailing westerly wind. (2) Convective systems pass by in the vicinity of the observation site, which persistently keep the lower δ18O in the air mass. Origin of the water vapor during June‐July‐August in 2003 is evaluated by the colored moisture analysis in which the tracers are assigned depending on the region where the water vapor finally evaporated. Seasonal mean result indicates that the regions contributing to precipitation in Mongolia are not low‐latitude regions but central Asia and western Siberia located to the northwest of Mongolia. Observed multilevel isotopic composition supports the model estimation. The moisture transport along the southwesterly wind of the Asian summer monsoon has difficulty reaching Mongolia as a monthly/seasonal mean perspective. However, eastern Mongolia and northeast China are situated on the border area between westerly wind moisture transport (by midlatitude synoptic cyclones) and southerly wind moisture transport (by Asian summer monsoon).
Cirrus optical properties observed with lidar, radiosonde, and satellite over the tropical Indian Ocean during the aerosol‐polluted northeast and clean maritime southwest monsoon
Authors: Seifert P. , Ansmann A. , Müller D. , Wandinger U. , Althausen D. , Heymsfield A. J. , Massie S. T. , Schmitt C.
Published: September 2007

Cirrus formation and geometrical and optical properties of tropical cirrus as a function of height and temperature are studied on the basis of INDOEX (Indian Ocean Experiment) lidar and radiosonde measurements and satellite observations of deep convection causing the generation of anvil cirrus. Lidar and radiosonde measurements were conducted at Hulule (4.1°N, 73.3°E), Maldives, during four field campaigns carried out in February–March 1999 and March 2000 (northeast (NE) monsoon season, characterized by increased concentrations of anthropogenic aerosols over the Indian Ocean) and in July and October 1999 (southwest (SW) monsoon season, characterized by clean maritime conditions). As a result of a stronger impact of deep convection on cirrus formation during the SW monsoon season, cirrus clouds covered the sky over the lidar site in only 35% (NE), but 64% (SW) of the measurement time. Subvisible cirrus (optical depth ≤0.03), thin (optical depth from 0.03 to 0.3), and opaque cirrus (optical depth ≥0.3) were observed in 18%, 48%, and 34% (NE) and in 8%, 52%, and 40% (SW) out of all cirrus cases, respectively. Mean midcloud heights were rather similar with values of 12.9 ± 1.5 km (NE) and 12.7 ± 1.3 km (SW). In 25% of the cases the cirrus top height was found close to the tropopause. Mean values of the multiple‐scattering‐corrected cirrus optical depth, cirrus layer mean extinction coefficient, and extinction‐to‐backscatter ratio were 0.25 ± 0.26 (NE) and 0.34 ± 0.29 (SW), 0.12 ± 0.09 km−1 (NE) and 0.12 ± 0.10 km−1 (SW), and 33 ± 9 sr (NE) and 29 ± 11 sr (SW), respectively. A functional dependency of the extinction coefficient of the tropical cirrus on temperature is presented. All findings are compared with several other cirrus lidar observations in the tropics, subtropics, and at midlatitudes. By contrasting the cirrus optical properties of the different seasons, a potential impact of anthropogenic particles on anvil cirrus optical properties was examined. Differences in the cirrus extinction‐to‐backscatter ratio suggest that NE monsoon anvil cirrus originating from deep‐convection cumulus clouds had more irregularly shaped and thus slightly larger ice crystals than respective SW monsoon anvil cirrus. Because the meteorological conditions were found to vary significantly between the seasons, an unambiguous identification of the influence of Asian haze on cirrus optical properties is not possible.
Spin transition and equations of state of (Mg, Fe)O solid solutions
Authors: Fei Yingwei , Zhang Li , Corgne Alexandre , Watson Heather , Ricolleau Angele , Meng Yue , Prakapenka Vitali
Published: September 2007

We have performed a series of experiments to investigate the compositional effect on the compression behavior of (Mg, Fe)O solid solutions at high pressure. The in‐situ synchrotron X‐ray diffraction data revealed abnormal volume contractions at about 40, 60, and 80 GPa for (Mg0.80, Fe0.20)O, (Mg0.61, Fe0.39)O, and (Mg0.42, Fe0.58)O, respectively. The volume contractions are associated with the reported electronic transition of high‐spin to low‐spin in Fe2+, and caused by the reduction of Fe2+ ionic radius across the transition. A least‐squares fit of the compression data to the Birch‐Murnaghan equation of state yielded bulk modulus K0 (GPa) = 160 − 10XFeO for the high‐spin (Mg,Fe)O and K0 = 170(3) GPa for the low‐spin (Mg,Fe)O. The equations of state of (Mg,Fe)O established in this study are directly applicable to the Earth's lower mantle in composition and pressure ranges and provide essential data for modeling the density profile of the lower mantle.
Diurnal hysteresis between soil CO2 and soil temperature is controlled by soil water content
Authors: Riveros‐Iregui Diego A. , Emanuel Ryan E. , Muth Daniel J. , McGlynn Brian L. , Epstein Howard E. , Welsch Daniel L. , Pacific Vincent J. , Wraith Jon M.
Published: September 2007

Recent years have seen a growing interest in measuring and modeling soil CO2 efflux, as this flux represents a large component of ecosystem respiration and is a key determinant of ecosystem carbon balance. Process‐based models of soil CO2 production and efflux, commonly based on soil temperature, are limited by nonlinearities such as the observed diurnal hysteresis between soil CO2 concentration ([CO2]) and temperature. Here we quantify the degree to which hysteresis between soil [CO2] and soil temperature is controlled by soil water content in a montane conifer forest, and how this nonlinearity impacts estimates of soil CO2 efflux. A representative model that does not consider hysteresis overestimated soil CO2 efflux for the entire growing season by 19%. At high levels of soil water content, hysteresis imposes organized, daily variability in the relationship between soil [CO2] and soil temperature, and at low levels of soil water content, hysteresis is minimized.
Drivers of declining sea ice in the Arctic winter: A tale of two seas
Authors: Francis Jennifer A. , Hunter Elias
Published: September 2007

While the summer perennial Arctic sea ice has declined markedly in recent decades, the maximum extent of the winter ice cover had decreased only slightly, until the past few years when it also receded dramatically. This investigation reveals that the timing of maximum extent varies greatly, and the drivers of ice‐edge location differ strikingly between two of the areas where it varies most: the Bering and Barents Seas. Between 1979 and 2005 in the Bering Sea, the ice edge is influenced mainly by anomalies in easterly winds associated with the Aleutian Low, which was particularly strong during the 1980s. The Barents Sea ice edge, in contrast, is driven primarily by two factors: anomalies in sea‐surface temperature, particularly close in time to the maximum extent, and by southerly wind (from the south) anomalies integrated back to mid‐ and early winter. The hemispheric‐mean decline in winter ice extent is due in large part to increasing sea‐surface temperatures in the Barents Sea and adjoining waters, which are consistent with increased concentrations of greenhouse gases.
Propagating uncertainty through prognostic carbon cycle data assimilation system simulations
Authors: Scholze M. , Kaminski T. , Rayner P. , Knorr W. , Giering R.
Published: September 2007

One of the major advantages of carbon cycle data assimilation is the possibility to estimate carbon fluxes with uncertainties in a prognostic mode, that is beyond the time period of carbon dioxide (CO2) observations. The carbon cycle data assimilation system is built around the Biosphere Energy Transfer Hydrology Scheme (BETHY) model, coupled to the atmospheric transport model TM2. It uses about 2 decades of observations of the atmospheric carbon dioxide concentration from a global network to constrain 57 process parameters via an adjoint approach. The model's Hessian matrix of second derivatives provides uncertainty estimates for the optimized process parameters that are consistent with the assumed uncertainties in the observations and the model. With those estimated parameter values, the model can predict the response of the terrestrial biosphere to prescribed climate forcing beyond the assimilation period. We develop a methodological framework that is able to propagate parameter uncertainties through such a prognostic simulation and provide uncertainty estimates for the simulation results. We demonstrate the concept for a 4‐year hindcast simulation from 2000 to 2003 following a 21‐year assimilation period from 1979 to 1999. We discuss prognostic uncertainties for surface fluxes and atmospheric carbon dioxide.
A novel approach to dissolution correction of Mg/Ca–based paleothermometry in the tropical Pacific
Authors: Mekik Figen , François Roger , Soon Maureen
Published: September 2007

Mg/Ca in planktonic foraminifers carries two main signals: calcification temperature and postdepositional test dissolution. Shell dissolution thus distorts water temperature reconstructions made with Mg/Ca in foraminifers. This problem could be resolved by quantifying the impact of carbonate dissolution on Mg/Ca with an independent, temperature‐insensitive deep‐sea calcite dissolution proxy, such as the Globorotalia menardii fragmentation index (MFI). To test the validity of this approach, we measured Mg/Ca in the tests of several planktonic foraminifers and MFI in core tops collected over a wide geographic region of the tropical Pacific and covering a wide range of deep‐sea calcite dissolution and seawater temperature. We confirm that Mg/Ca from different species have different susceptibility to temperature and dissolution. Mg/Ca in surface‐dwelling Globigerina bulloides is controlled by calcification temperature and is largely unaffected by carbonate dissolution estimated from MFI. In contrast, Mg/Ca in deeper dwelling G. menardii is minimally sensitive to temperature and dominantly affected by dissolution. Mg/Ca in Neogloboquadrina dutertrei and Pulleniatina obliquiloculata are significantly affected by both temperature and dissolution, and MFI can be effectively used to correct temperature estimates from these species for calcite dissolution. Additional variables besides temperature and dissolution appear to control Mg/Ca in Globorotalia tumida, and their identification is a prerequisite for interpreting elemental shell composition in this species. Combining down‐core measurements of Mg/Ca in multiple foraminifer species with MFI provides a powerful tool for reconstructing past changes in the upper water column temperature structure in the tropical Pacific.
Multipole‐Free Fast Inhomogeneous Plane Wave Algorithm
Authors: Saville M. A. , Chew W. C.
Published: September 2007

Solving radiation and scattering problems in the vicinity of a half‐space or stratified medium with integral equation methods is complicated, and slowed by computation of expensive Sommerfeld integrals. In this paper, a new formulation of the spectral layered media Green's function is presented. It is demonstrated for a simple scattering problem in the new fast algorithm called the Multipole‐Free Fast Inhomogeneous Plane Wave Algorithm (MF‐FIPWA). MF‐FIPWA is shown to scale as (N log N) in memory usage and processing time. Additional advantages include rigorous treatment of reflected contributions, simplicity in design, and mathematical insight into the fast algorithm.
Effect of organic forms of phosphorus and variable concentrations of sulfide on the metabolic generation of soluble-reactive phosphate by sulfur chemolithoautotrophs: a laboratory study
Authors: Guhathakurta Himadri , Biswas Raka , Dey Prabuddha , Mahapatra Piyali Gajendra , Mondal Bipasha
Published: September 2007

In aquatic systems, recycling of phosphorus (P) is strongly influenced by microbial metabolic responses. This study was designed to look at the generation of P (as soluble-reactive phosphate (SRP)) from organic P-enriched sediments by benthic sulfur chemolithoautotrophs. The study revealed that microbial density was greater in organic P-enriched sediments when compared to sediments without added organic P and the presence of organic P significantly influenced mobilization of SRP from sediment. Generation of SRP by sediment microbes was cumulative, dependent on time. The results indicated dissolved sulfide (S2−) to be necessary for initiation of the metabolism-related mobilization of P: there was no statistically significant effect of variations in ambient concentrations of sulfide (S2−). The results elucidate possible outcomes of addition of organic P in aquatic ecosystems.
The use of stable isotope probing to identify key iron-reducing microorganisms involved in anaerobic benzene degradation
Authors: Kunapuli Umakanth , Lueders Tillmann , Meckenstock Rainer U
Published: September 2007

Here, we present a detailed functional and phylogenetic characterization of an iron-reducing enrichment culture maintained in our lab with benzene as sole carbon and energy source. We used DNA-stable isotope probing to identify microbes within the enrichment most active in the assimilation of 13C-label. When 12C6- and 13C6-benzene were added as comparative substrates, marked differences in the quantitative buoyant density distribution became apparent especially for uncultured microbes within the Gram-positive Peptococcaceae, closely related to environmental clones retrieved from contaminated aquifers world wide and only distantly related to cultured representatives of the genus Thermincola. Prominent among the other constituents of the enrichment were uncultured Deltaproteobacteria, as well as members of the Actinobacteria. Although their presence within the enrichment seems to be stable they did not assimilate 13C-label as significantly as the Clostridia within the time course of our experiment. We hypothesize that benzene degradation in our enrichment involves an unusual syntrophy, where members of the Clostridia primarily oxidize benzene. Electrons from the contaminant are both directly transferred to ferric iron by the primary oxidizers, but also partially shared with the Desulfobulbaceae as syntrophic partners. Alternatively, electrons may also be quantitatively transferred to the partners, which then reduce the ferric iron. Thus our results provide evidence for the importance of a novel clade of Gram-positive iron-reducers in anaerobic benzene degradation, and a role of syntrophic interactions in this process. These findings shed a totally new light on the factors controlling benzene degradation in anaerobic contaminated environments.
Significance of Plant Sulfite Oxidase
Authors: Hänsch R. , Lang C. , Rennenberg H. , Mendel R. R.
Published: September 2007

Abstract: Sulfite oxidizing activities are known since years in animals, microorganisms, and also plants. Among plants, the only enzyme well characterized on molecular and biochemical level is the molybdoenzyme sulfite oxidase (SO). It oxidizes sulfite using molecular oxygen as electron acceptor, leading to the production of sulfate and hydrogen peroxide. The latter reaction product seems to be the reason why plant SO is localized in peroxisomes, because peroxisomal catalase is able to decompose hydrogen peroxide. On the other hand, we have indications for an additional reaction taking place in peroxisomes: sulfite can be nonenzymatically oxidized by hydrogen peroxide. This will promote the detoxification of hydrogen peroxide especially in the case of high amounts of sulfite. Hence we assume that SO could possibly serve as “safety valve” for detoxifying excess amounts of sulfite and protecting the cell from sulfitolysis. Supportive evidence for this assumption comes from experiments where we fumigated transgenic poplar plants overexpressing Arabidopsis SO with SO2 gas. In this paper, we try to explain sulfite oxidation in its co‐regulation with sulfate assimilation and summarize other sulfite oxidizing activities described in plants. Finally we discuss the importance of sulfite detoxification in plants.
Electric double layer effect on observable characteristics of the tunnel current through a bridged electrochemical contact
Authors: Kuznetsov Alexander M. , Medvedev Igor G. , Ulstrup Jens
Published: September 2007

Scanning tunneling microscopy and electrical conductivity of redox molecules in conducting media (aqueous or other media) acquire increasing importance both as novel single-molecule science and with a view on molecular scale functional elements. Such configurations require full and independent electrochemical potential control of both electrodes involved. We provide here a general formalism for the electric current through a redox group in an electrochemical tunnel contact. The formalism applies broadly in the limits of both weak and strong coupling of the redox group with the enclosing metal electrodes. Simple approximate expressions better suited for experimental data analysis are also derived. Particular attention is given to the effects of the Debye screening of the electric potential in the narrow tunneling gap based on the limit of the linearized Poisson-Boltzmann equation. The current/overpotential relation shows a maximum at a position which depends on the ionic strength. It is shown, in particular, that the dependence of the maximum position on the bias voltage may be nonmonotonous. Approximate expressions for the limiting value of the slope of the current/overpotential dependence and the width of the maximum on the bias voltage are also given and found to depend strongly on both the Debye screening and the position of the redox group in the tunnel gap, with diagnostic value in experimental data analysis.
Formation of density singularities in ideal hydrodynamics of freely cooling inelastic gases: A family of exact solutions
Authors: Fouxon Itzhak , Meerson Baruch , Assaf Michael , Livne Eli
Published: September 2007

We employ granular hydrodynamics to investigate a paradigmatic problem of clustering of particles in a freely cooling dilute granular gas. We consider large-scale hydrodynamic motions where the viscosity and heat conduction can be neglected, and one arrives at the equations of ideal gas dynamics with an additional term describing bulk energy losses due to inelastic collisions. We employ Lagrangian coordinates and derive a broad family of exact nonstationary analytical solutions that depend only on one spatial coordinate. These solutions exhibit a new type of singularity, where the gas density blows up in a finite time when starting from smooth initial conditions. The density blowups signal formation of close-packed clusters of particles. As the density blow-up time tc is approached, the maximum density exhibits a power law ∼(tc−t)−2. The velocity gradient blows up as ∼−(tc−t)−1 while the velocity itself remains continuous and develops a cusp (rather than a shock discontinuity) at the singularity. The gas temperature vanishes at the singularity, and the singularity follows the isobaric scenario: the gas pressure remains finite and approximately uniform in space and constant in time close to the singularity. An additional exact solution shows that the density blowup, of the same type, may coexist with an “ordinary” shock, at which the hydrodynamic fields are discontinuous but finite. We confirm stability of the exact solutions with respect to small one-dimensional perturbations by solving the ideal hydrodynamic equations numerically. Furthermore, numerical solutions show that the local features of the density blowup hold universally, independently of details of the initial and boundary conditions.
Energy decompositions according to physical space partitioning schemes: Treatments of the density cumulant
Authors: Alcoba Diego R. , Torre Alicia , Lain Luis , Bochicchio Roberto C.
Published: September 2007

This article is a continuation of our previous paper on schemes of energy decompositions of molecular systems in the real space [D. R. Alcoba et al., J. Chem. Phys. 122, 074102 (2005)] now using correlated state functions. We study, according to physical arguments, the appropriate management of the density cumulant arising from the second-order reduced density matrix at correlated level, whose contributions can be assigned to one-center or to two-center terms in the energy partitioning. Our treatments are applied within two physical space partitioning schemes: the Bader partitioning into atomic basins and the fuzzy atom procedure. The results obtained in selected molecules are analyzed and discussed in detail.
Surface defects and their influence on structural and photoluminescence properties of CdWO4:Eu3+ nanocrystals
Authors: Dai Qilin , Song Hongwei , Pan Guohui , Bai Xue , Zhang Hui , Qin Ruifei , Hu Lanying , Zhao Haifeng , Lu Shaozhe , Ren Xinguang
Published: September 2007

CdWO 4 :Eu 3 + nanocrystals were prepared by the hydrothermal method at different pH values (pH=4, 7.5, and 10) and annealed at different temperatures. Their structural and photoluminescence properties were systemically studied. The studies on electron spin resonance and Fourier-transfer infrared absorption spectra demonstrated that at least two kinds of surface defects were involved, the surface dangling bonds of transition metals and the surface adsorption of the OH− and CO32− groups. The surface adsorption in the pH=10 sample increased considerably, which led the surface dangling bonds to decrease and even to disappear. Due to the existence of surface defect states, especially the surface dangling bonds, tungstates at two symmetry sites were formed, the normal site and the perturbed site locating at/near the surface. The former tungstates located at high energy side (∼290 nm) in the excitation bands and emitted blue-green photons, while the latter located at low energy (∼340 nm) and emitted red photons. They can both effectively transfer the energies to Eu3+ ions, generating red D50-F7J transitions. As the nanocrystalline powders were annealed, colorations appeared and evolved with temperature, while the surface dangling bonds and surface adsorption gradually disappeared. The defect states had great and complicated influence on luminescence efficiency, luminescent stability, and temperature-stability of tunstates and Eu3+ ions.
Fourier transform-based k⋅p method of semiconductor superlattice electronic structure
Authors: Mei T.
Published: September 2007

With the periodic spatial domain Hamiltonian being expressed as a Fourier series, a simple and neat Hamiltonian in a Fourier domain is formulated. The Fourier transform-based k⋅p approach is developed to calculate electronic structures of semiconductor heterostructures. Calculation of electronic structures is investigated with several quantum well examples and comparison is made between this approach and the finite difference approach. The formulation of the Fourier domain Hamiltonian for quantum dots is presented as well.
Inversion layer formation in organic field-effect devices
Authors: Lindner Th. , Paasch G.
Published: September 2007

One of the challenges for polymer electronics is the realization of complementary metal-oxide-semiconductor circuits, requiring both n- and p-channel transistors on the chip. The difficulty to create both accumulation and inversion layers in the same material has been attributed to obstacles to the synthesis of metallic source/drain contacts for efficient injection of both electrons and holes, and also to the fact that the electron and hole mobilities differ often by several orders of magnitude. Although the formation of inversion layers has been well understood in microelectronics, it has to be studied anew for organics, since the mobility and the intrinsic density are many orders of magnitude lower. An analytical estimate of the relation between relevant characteristic times reveals the peculiarities occurring in the organics. Detailed insight is obtained from a numerical simulation study for metal-oxide-semiconductor capacitors and transistors of different design. In simulated quasistatic capacitance-voltage characteristics hysteresis effects are obtained due to the inversion layer formation process. This mechanism can be understood by inspecting the internal density profiles obtained by the simulation. In addition, capaci-tance-frequency characteristics are simulated and analyzed in more detail with equivalent circuit models that describe the simulated characteristics well. Here, the relaxation times characterizing the transition between the maximum capacitance and the geometrical capacitance are determined by resistances and capacitances of sublayers, which can be ascribed different regions as oxide, bulk, depletion, accumulation, or inversion. Both the design and the source/drain contact properties influence the characteristics significantly.
Integrated silicon nanowire diodes and the effects of gold doping from the growth catalyst
Authors: Jackson Justin B. , Kapoor Divesh , Jun Sun-Gon , Miller Mark S.
Published: September 2007

We report on integrated, silicon single-nanowire diodes. Gold catalyst templates, defined by lithography, controlled the location of nanowires grown with a vapor-liquid-solid mechanism. The nanowire growth, by atmospheric-pressure chemical vapor deposition, used SiCl4 diluted in H2 on (100) n-type silicon substrates. Postgrowth oxidation and wet etching reduced the nanowire diameters and removed unintentional small diameter nanowires. Spin-on glass isolated the nanowire tips from the substrate, which were then contacted with aluminum. Current-voltage measurements show rectification and ideality factors consistent with pn junction diodes. However, the gold catalyzed nanowires have much higher than expected hole concentrations that cannot be explained by behaviors reported for gold diffused into silicon.
Enhancement of photoluminescence emission in low-dimensional structures formed by irradiation of laser
Authors: Huang Wei-Qi , Xu Li , Wu Ke-Yue , Liu Shi-Rong
Published: September 2007

We report the fabrication of low-dimensional structures by irradiation of a laser on the silicon sample and on the SiGe alloy sample. The physical mechanism forming a kind of hole-net structure of silicon could be explained with the theory of the harmonic standing wave of plasma. The article has studied the enhancement of the photoluminescence (PL) in the hole-net structure of silicon and in the porous structure of SiGe. The optimum condition in the preparing process is found to make a stable sample which has an intensive PL emission. The effect of the enhancement of the PL emission in the low-dimensional structures cannot be interpreted within the quantum confinement (QC) theory alone. So a model for explaining the effect is proposed in which the trap states of the interface between SiO2 and low-dimensional nanocrystal play an important role.
Band offsets between amorphous LaAlO3 and In0.53Ga0.47As
Authors: Goel N. , Tsai W. , Garner C. M. , Sun Y. , Pianetta P. , Warusawithana M. , Schlom D. G. , Wen H. , Gaspe C. , Keay J. C. , Santos M. B. , Goncharova L. V. , Garfunkel E. , Gustafsson T.
Published: September 2007

The band offsets between an amorphous LaAlO3 dielectric prepared by molecular-beam deposition and a n-type In0.53Ga0.47As (001) layer have been measured using synchrotron radiation photoemission spectroscopy. The valence and conduction band offsets at the postdeposition annealed LaAlO3∕InGaAs interface are 3.1±0.1 and 2.35±0.2eV, respectively. The band gap of LaAlO3, as determined by Al 2p and O 1s core level energy loss spectra, is 6.2±0.1eV. Within the resolution of the medium energy ion scattering technique, no interfacial oxide layer is seen between the InGaAs and the 3.6nm thick amorphous LaAlO3.
Wide angle crystal spectrometer for angularly and spectrally resolved x-ray scattering experiments
Authors: García Saiz E. , Khattak F. Y. , Gregori G. , Bandyopadhyay S. , Clarke R. J. , Fell B. , Freeman R. R. , Jeffries J. , Jung D. , Notley M. M. , Weber R. L. , van Woerkom L. , Riley D.
Published: September 2007

A novel wide angle spectrometer has been implemented with a highly oriented pyrolytic graphite crystal coupled to an image plate. This spectrometer has allowed us to look at the energy resolved spectrum of scattered x rays from a dense plasma over a wide range of angles (∼30°) in a single shot. Using this spectrometer we were able to observe the temporal evolution of the angular scatter cross section from a laser shocked foil. A spectrometer of this type may also be useful in investigations of x-ray line transfer from laser-plasmas experiments.