bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffusion of drugs from hydrogels and liposomes as drug carriers
Authors: Pjanović Rada , Bošković‐Vragolović Nevenka , Veljković‐Giga Jelena , Garić‐Grulović Radmila , Pejanović Srdjan , Bugarski Branko
Published: February 2010

BACKGROUND: The mass transfer of model drugs Lidocaine hydrochloride and Dihydroquercetin from hydrogels (the usual carriers for topical drugs), and hydrogels containing liposomes, as novel drug vehicles, was studied. Diffusion experiments were performed using a Franz diffusion cell. Experimental data were used to calculate drug diffusion coefficients across membranes, and their effective diffusion coefficients from hydrogels and liposome containing hydrogels. For the first time the diffusion resistance of all drug carriers was determined from corresponding diffusion coefficients.

The main aim of this work was the study of drug diffusion coefficients from liposomes and their comparison with related diffusion coefficients from hydrogels to find how liposomes contribute to prolonged and controlled drug release.

RESULTS: Drug diffusion coefficients were: 1.38 · 10−8m2 s−1 for Lidocaine hydrochloride and 5.96 · 10−9m2 s−1 for Dihydroquercetin, while corresponding effective diffusion coefficients from hydrogels were: 7.82 · 10−10m2 s−1 and 7.98 · 10−10m2 s−1, respectively. Effective diffusion coefficients from liposome‐containing hydrogels were:4.82 · 10−10m2 s−1 (Lidocaine hydrochloride) and 4.305 · 10−10m2 s−1 (Dihydroquercetin). Diffusion resistances for the two hydrogels were almost the same. Very similar values of diffusion resistances for all liposome dispersions were obtained.

CONCLUSION: Calculated diffusion coefficients and resistances demonstrate that liposomes, as drug carriers, significantly affect diffusion rates. The results obtained could be used whenever diffusion‐controlled drug release is required. Copyright © 2010 Society of Chemical Industry
The influence of plant polyphenols on lipolysis and biohydrogenation in dried forages at different phenological stages: in vitro study
Authors: Cabiddu Andrea , Salis Lorenzo , Tweed John KS , Molle Giovanni , Decandia Mauro , Lee Michael RF
Published: February 2010

BACKGROUND: It is known that forage legumes show a higher transfer efficiency of polyunsaturated fatty acids (PUFA) to ruminant dairy products in comparison with grasses. Legumes are usually characterised by moderate levels of plant secondary metabolites, which can have an effect on lipolysis and biohydrogenation in the rumen. An in vitro study was carried out to compare two species with different plant phenol compositions, Vicia sativa (VS, common vetch, cv. Jose) and Trifolium incarnatum (TI, crimson clover, cv. Viterbo) cut at the vegetative (Veg) and reproductive (Rep) stages, on lipolysis and PUFA biohydrogenation in the rumen.

RESULTS: The study showed that forage species and phenological stage affected the levels of bound phenols (BP) and tannic polyphenols (TP). VS was characterised by a higher level of TP than TI at both Veg and Rep stages, whereas BP levels were low in both forages. BP and TP had a negative effect on lipolysis and biohydrogenation, but TP showed a greater negative correlation than BP for both forages.

CONCLUSION: These results showed that lipolysis and biohydrogenation of PUFA could be affected by plant phenols, particularly TP. Copyright © 2010 Society of Chemical Industry
Microbial inhibitory and radical scavenging activities of cold‐pressed terpeneless Valencia orange (Citrus sinensis) oil in different dispersing agents
Authors: Chalova Vesela I , Crandall Philip G , Ricke Steven C
Published: February 2010

BACKGROUND: Due to their low solubility in water, oil‐based bioactive compounds require dispersion in a surface‐active agent or appropriate solvents to ensure maximum contact with microorganisms. These combinations, however, may change their physical and/or chemical characteristics and consequently alter the desired functionality. The objective of this study was to determine the impact of selected dispersing agents, ethanol, dimethyl sulfoxide (DMSO), and Tween‐80, on cold‐pressed terpeneless (CPT) Valencia orange oil to function as a free radical scavenger and an antimicrobial food additive.

RESULTS: When dissolved in ethanol or DMSO, the orange oil fraction had similar minimum inhibitory concentrations (MIC) for Listeria monocytogenes ATCC 19 115 (0.3% and 0.25% v/v respectively), which were significantly lower (P ≤ 0.5) than the MIC for Salmonella typhimurium ATCC 14 028 (1% v/v). Both ethanol and DMSO oil dispersion systems exhibited an intermediate MIC (0.75% v/v) for Lactobacillus plantarum WCFS1. The orange oil (up to 3%) in an aqueous solution of 0.1% Tween‐80 yielded no inhibitory activities against any of the test bacteria. However, the 1% natural orange oil dispersed in Tween‐80 exhibited 56.86% 2,2‐diphenyl‐1‐picryl hydrazyl (DPPH) radical inhibition versus 18.37% and 16.60% when the same level of orange oil was dissolved in DMSO or ethanol, respectively. At the same orange oil concentration, the oil/Tween‐80 suspension yielded 57.92% neutralization of hydroxyl radicals. This represents 71.37% of the mannitol antioxidant activity, which was used as a positive control.

CONCLUSIONS: These findings suggest that Tween‐80 is an appropriate dispersing agent only if the antioxidant functionality is desired. If both antimicrobial and antioxidant properties are needed, the CPT Valencia orange oil should be dispersed in either DMSO or ethanol. Copyright © 2010 Society of Chemical Industry
Influence of pre‐cure freezing on the profile of volatile compounds during the processing of Iberian hams
Authors: Pérez‐Palacios Trinidad , Ruiz Jorge , Martín Diana , Grau Raúl , Antequera Teresa
Published: February 2010

BACKGROUND: This work was designed to study the effect of pre‐cure freezing of raw thighs from Iberian pigs on the profile of volatile compounds during the processing of hams.

RESULTS: Generation of volatile compounds during Iberian ham processing was similar in both pre‐cure frozen and refrigerated hams, the main differences being at the final stage. The levels of 2‐methylbutanal, 2‐methyl‐1‐butanol, 2,3‐butanediol and 2‐heptanol were significantly higher in dry‐cured hams that were pre‐cure frozen than in refrigerated ones, whereas the content of most detected esters was statistically lower in pre‐cure frozen than in refrigerated hams.

CONCLUSION: The effect of pre‐cure freezing of Iberian ham on the profile of volatile compounds during ripening was not remarkable. Few differences were found in the final product, which would not greatly modify the aroma and flavour features of the dry‐cured hams. Copyright © 2010 Society of Chemical Industry
Einzelmolekülmethoden zur Genomsequenzierung
Authors: Groß Michael
Published: February 2010

Die gegenwärtig genutzten Genomsequenzierer der zweiten Generation sind nur ein Übergang. Es ist heute bereits möglich, einzelne DNA‐Moleküle zu sequenzieren.
Long‐term follow‐up of children with ovarian cysts diagnosed prenatally
Authors: Ben‐Ami Ido , Kogan Adi , Fuchs Noga , Smorgick Noam , Mendelovic Sonia , Lotan Gagi , Herman Arie , Maymon Ron
Published: February 2010

Objective

To assess long‐term outcomes of children who had ovarian cysts diagnosed prenatally.

Methods

We reviewed prenatal records of fetuses diagnosed with ovarian cysts in our ultrasound unit between January 1997 and December 2008. During January–April 2009, those children were invited to our institute for transabdominal pelvic sonographic re‐examination. Demonstration of the uterus and adnexa was required.

Results

Twenty‐one children were diagnosed prenatally with either simple (n = 11) or complex (n = 12) ovarian cysts and treated by either conservative management (n = 13) or surgical intervention (n = 10) postnatally. The ipsilateral ovary was not detected in 8 of 11 children in whom a complex cyst had been detected on the first postnatal scan. Significantly higher rate of ovarian loss was diagnosed when the sonographic appearance of the ovarian cyst was simple on the prenatal scan and complex on the postnatal scan (six of seven) compared with when the ovarian cyst was simple on both scans (one of four, P = 0.04).

Conclusion

Prenatal detection of complex ovarian cyst might indicate close monitoring in order to alert the need for early intervention for preventing impending ovarian loss. Further researches are needed to empower this study. Copyright © 2010 John Wiley & Sons, Ltd.
The pairing symmetry in the ferromagnetic superconductor UGe2
Authors: Garcia F. A. , Cabrera G. G.
Published: February 2010

We give an extensive treatment of the pairing symmetry in the ferromagnetic (FM) superconductor UGe2. We show that one can draw important conclusions concerning the superconducting state, considering only the transformation properties of the pairing function, without assumptions about the form of the pairing amplitudes.
Psychosocial working conditions, school sense of coherence and subjective health complaints. A multilevel analysis of ninth grade pupils in the Stockholm area
Authors: Modin Bitte , Östberg Viveca , Toivanen Susanna , Sundell Knut
Published: February 2010

This study explores the psychosocial working conditions of 7930 Swedish 9th grade students, distributed over 475 classes and 130 schools, in relation to their subjective health using multilevel modeling. At the individual level, students with “strained” working conditions in school (i.e. those experiencing a high level of demands in combination with a low level of control) demonstrated significantly worse health compared to students in “low‐strain” situations. “Strained” conditions in combination with a weak school‐related sense of coherence were especially unfavourable for health. These findings remained significant when support from teachers, school marks, norm‐breaking behaviours, family‐relations and certain class‐ and school‐contextual conditions were adjusted for. Thus, while demands are an essential part of school work, this study suggests that high levels of control and a strong school‐related sense of coherence can protect against the more detrimental effects on health that high demands at school may cause.
From the Klein–Gordon–Zakharov system to a singular nonlinear Schrödinger system
Authors: Masmoudi Nader , Nakanishi Kenji
Published: February 2010

In this paper, we continue our investigation of the high-frequency and subsonic limits of the Klein–Gordon–Zakharov system. Formally, the limit system is the nonlinear Schrödinger equation. However, for some special case of the parameters going to the limits, some new models arise. The main object of this paper is the derivation of those new models, together with convergence of the solutions along the limits.

Dans cet article, on continue l'investigation des limites haute fréquence et subsonique du système de Klein–Gordon–Zakharov. Formellement, le système limite est le système de Schrödinger nonlinéaire. Cependant, pour un cas particulier des paramètres, on trouve un nouveau modèle qui contient un terme singulier. L'objet de ce papier est de donner une dérivation rigoureuse de ce modèle et de montrer la convergence dans l'espace d'énergie.
Recognition of cellooligosaccharides by a family 28 carbohydrate‐binding module
Authors: Tsukimoto Kazuhide , Takada Rie , Araki Yuko , Suzuki Kentaro , Karita Shuichi , Wakagi Takayoshi , Shoun Hirofumi , Watanabe Takashi , Fushinobu Shinya
Published: February 2010

The crystal structures of a carbohydrate‐binding module (CBM) family 28 domain of endoglucanase Cel5A from Clostridium josui have been determined in ligand‐free and complex forms with cellobiose, cellotetraose, and cellopentaose as the first complex structures of this family. In the cleft of a β‐sandwich fold, the ligands are recognized by stacking interactions and hydrogen bonds. Conformations of the bound cellooligosaccharides are similar to those in crystals and solution but clearly different from the cellulose structure. Interestingly, the glucan chain bound on CBM28 is in the opposite direction of that bound to CBM17, although these families share significant structural similarity.
TPCs: Endolysosomal channels for Ca2+ mobilization from acidic organelles triggered by NAADP
Authors: Zhu Michael X. , Ma Jianjie , Parrington John , Galione Antony , Mark Evans A.
Published: February 2010

Two‐pore channels (TPCs or TPCNs) are novel members of the large superfamily of voltage‐gated cation channels with slightly higher sequence homology to the pore‐forming subunits of voltage‐gated Ca2+ and Na+ channels than most other members. Recent studies demonstrate that TPCs locate to endosomes and lysosomes and form Ca2+ release channels that respond to activation by the Ca2+ mobilizing messenger, nicotinic acid adenine dinucleotide phosphate (NAADP). With multiple endolysosomal targeted NAADP receptors now identified, important new insights into the regulation of endolysosomal function in health and disease will therefore be unveiled.
Site‐directed mutagenesis and PBAN activation of the Helicoverpa zea PBAN‐receptor
Authors: Choi Man-Yeon , Jurenka Russell A.
Published: February 2010

Pheromone biosynthesis‐activating neuropeptide (PBAN) and pyrokinins belong to a family of insect peptide hormones that have a common FXPRLamide C‐terminal ending. The G‐protein‐coupled receptors (GPCRs) for this peptide family were first identified from a moth and Drosophila with sequence similarity to neuromedin U receptors from vertebrates. We have characterized the PBAN‐receptor (PBAN‐R or PR) active binding domains using chimeric GPCRs and proposed that extracellular loop 3 is critical for ligand selection. Here, we characterized the 3rd extracellular domain of PBAN‐R through site‐directed point mutations. Results are discussed in context of the structural features required for receptor activation using receptor activation experiments and in silico computational modeling. This research will help in characterizing these receptors towards a goal of finding agonists and/or antagonists for PBAN/pyrokinin receptors.
High‐intensity focused ultrasound treatment for non‐neoplastic epithelial disorders of the vulva
Authors: Ruan Liming , Xie Zhenwei , Wang Huiyun , Jiang Jingyi , Shi Haiyan , Xu Jian
Published: February 2010

Objective

To assess the efficacy of high‐intensity focused ultrasound (HIFU) treatment in patients with non‐neoplastic epithelial disorders of the vulva.

Method

We reviewed 41 cases of lichen sclerosus, 38 cases of squamous cell hyperplasia, and 17 mixed cases treated by HIFU from April 2004 to July 2008 at the Women's Hospital of Zhejiang University School of Medicine. Biopsy specimens were assessed with light microscopy before and after treatment.

Results

Pruritus and signs of vulvar lesions were dramatically improved following HIFU treatment, without severe complications, and 90.23% of the patients were cured or had their symptoms improved 6 months after treatment. On light microscopy, pigmentation and epithelial structures were recovered and dermal lymphocytic infiltration was reduced. The response rates were lower and complication rates higher among lichen sclerosus than among squamous cell hyperplasia cases (P < 0.05 for both).

Conclusion

Treatment with HIFU may be safe and effective in cases of vulvar dystrophy.
Outcome following splenectomy in cats
Authors: Gordon Sebastian S.N. , McClaran Janet K. , Bergman Philip J. , Liu Serena M.
Published: February 2010

No studies have yet examined whether there are prognostic factors for survival for cats undergoing splenectomies. The medical records of 19 cats that had complete splenectomy were reviewed for information on preoperative, intraoperative, and postoperative factors. The most common presenting signs were a palpable abdominal mass in 58% and anorexia in 47% of the cats. Mast cell tumors were the most common reason for splenectomy and were found in 10/19 cats (53%); followed by hemangiosarcoma in 4/19 (21%); and lymphoma in 2/19 (11%). The Kaplan–Meier median survival time (MST) was 197 days, with a range from 2 days to 1959 days. Three cats were noted to have preoperative weight loss, and this was the only factor that had prognostic significance for survival following surgery. For cats with weight loss the MST was 3 days, for cats with no weight loss noted the MST was 293 days ( P=0.008).
Fundamental indexing around the world
Authors: Walkshäusl Christian , Lobe Sebastian
Published: February 2010

Using an international sample from 1982 to 2008, we investigate the performance of global and 50 country‐specific (28 developed and 22 emerging) fundamentally weighted portfolios compared to capitalization‐weighted portfolios. First, we establish that superior performance of domestic portfolios diminishes considerably when applying a bootstrap procedure for robust performance testing. Second, after controlling for data snooping biases and the value premium, we find evidence of outperforming global fundamental indexes, but no compelling evidence of outperforming country‐specific indexes.
Latitudinal and Downcore (0–750 ka) Changes in Nalkane Chain Lengths in the Eastern Equatorial Pacific
Authors: Horikawa Keiji , Murayama Masafumi , Minagawa Masao , Kato Yoshihisa , Sagawa Takuya
Published: February 2010

The n-alkane C31/(C29+C31) ratios from surface sediments in the eastern equatorial Pacific (EEP) exhibit higher values to the north and lower values to the south across the southern edge (2–4°N) of the Intertropical Convergence Zone (ITCZ). Since plants tend to synthesize longer chain length n-alkanes in response to elevated temperature and/or aridity, the higher C 31/(C29+C31) ratios at northern sites suggest a higher contribution of vegetation under hot and/or dry conditions. This is consistent with the observation that northern sites receive higher levels of plant waxes transported by northeasterly trade winds from northern South America, where hot and dry conditions prevail. Furthermore, from a sediment core covering the past 750 ka (core HY04; 4°N, 95°W) we found that C31/(C29+C31) ratios exhibit a long-term decrease from MIS (marine oxygen isotope stage) 17 to 13. During this period, the zonal SST (sea-surface temperature) gradient in the equatorial Pacific increased, suggesting an increase in Walker circulation. Such intensified Walker circulation may have enhanced moisture advection from the equatorial Atlantic warm pool to the adjacent northern South America, causing arid regions in northern South America to contract, which may explain long-term decrease in n-alkane chain lengths.
The Influence of Pretreatment Chemistry on the Radiocarbon Dating of Campanian Ignimbrite-Aged Charcoal from Kostenki 14 (Russia)
Authors: Douka Katerina , Higham Thomas , Sinitsyn Andrey
Published: February 2010

The presence of an independently dated marker in an archaeological site offers rare opportunities for assessing the reliability of radiocarbon dates, especially when these are close to the age limit of the technique. Two different pretreatment protocols (routine ABA and more rigorous ABOx-SC) were employed in the chemical preparation of the same charcoal sample from a layer closely associated to the Campanian Ignimbrite tephra at the Russian Palaeolithic site of Kostenki 14 (Markina Gora). The ABA-treated fraction gave an age of ∽33 14C ka BP, comparable to a previous determination from the same layer, whereas the ABOx-SC produced an older age of ∽35 14C ka BP. This is the first radiocarbon determination of an archaeological sample to provide an age consistent with the "calendar" age for the CI tephra marker.
Fritillaria ragusinasp. nov., a new species of Appendicularia (Tunicata) from the Adriatic Sea
Authors: Garić Rade , Batistić Mirna
Published: February 2010

A new species of appendicularian,Fritillaria ragusina, is described from specimens collected between the surface and 300 m depth at three stations in the open south Adriatic Sea (north-eastern Mediterranean).Fritillaria ragusinais characterized by a broad trunk–tail connection created by a wide tail fin in the initial part of the tail, sloping shoulders of the tail fin, broad tail musculature, multiple fusiform amphichordal cells along the edge of the tail musculature and small size at sexual maturity (maximum recorded trunk length of 445 µm and maximum recorded tail length of 960 µm). Maximum abundance, 2.4 ind m−3, was found within the 0–50 m layer.
Selection of Apis mellifera workers by the parasitic mite Varroa destructor using host cuticular hydrocarbons
Authors: PICCOLO F. DEL , NAZZI F. , VEDOVA G. DELLA , MILANI N.
Published: February 2010

The parasitic mite, Varroa destructor, is the most important threat for apiculture in most bee-keeping areas of the world. The mite is carried to the bee brood cell, where it reproduces, by a nurse bee; therefore the selection of the bee stage by the parasite could influence its reproductive success. This study investigates the role of the cuticular hydrocarbons of the European honeybee (Apis mellifera) in host-selection by the mite. Preliminary laboratory bioassays confirmed the preference of the varroa mite for nurse bees over pollen foragers. GC-MS analysis of nurse and pollen bees revealed differences in the cuticular hydrocarbons of the two stages; in particular, it appeared that pollen bees have more (Z)-8-heptadecene than nurse bees. Laboratory experiments showed that treatment of nurse bees with 100 ng of the pure compound makes them repellent to the varroa mite. These results suggest that the mite can exploit the differences in the cuticular composition of its host for a refined selection that allows it to reach a brood cell and start reproduction. The biological activity of the alkene encourages further investigations for the development of novel control techniques based on this compound.
Zur Geschichte der deutschen Polizeiliteratur im 19. Jahrhundert
Authors: Stein H.
Published: February 2010

In Nr. 2/1937 unseres Bulletins haben wir über eine vergessene deutsche Polizeipublikation, den Anzeiger für die politische Polizei Deutschlands berichtet. Inzwischen hat unser Institut eine seltene Schrift erwerben können, die sich mit der deutschen Polizeiliteratur, darunter auch mit dem Anzeiger recht kritisch befasst und allerlei aufschlussreiches Material über die Tätigkeit der politischen Polizei der 1850er Jahre beibringt. Es handelt sich um die 123 Seiten starke Broschüre von A. Vandermeulen, Enthüllungen aus der höheren Region der politischen Spionage, in Berichten eines ungarischen Judas Ischarioth. Nebst sonstigen Aufdeckungen in Bezug auf das Treiben der geheimen Polizei. Verlag von Reinhold Schlingmann, Berlin 1862.
Cross-Section Sample Preparation of a Free-Standing Thin-Film Coupon
for Transmission Electron Microscopy Analysis
Authors: Phelps John M.
Published: February 2010

A method for preparing a cross-section sample from a free-standing
thin-film coupon suitable for transmission electron microscopy analysis
has been successfully developed. The free-standing coupon presented a
significant challenge for the preparation of a cross-section sample. A
stack consisting of a silicon wafer, thin-film coupon, and glass coverslip
was epoxied together, providing both support for thin film and enough
surface area to handle the specimen during the sample preparation
procedure. The tripod polisher wedge technique was used to thin the
cross-section sample to 2 to 5 μm in thickness. This produced a sample
with the required structural integrity. Final thinning was accomplished
using an ion mill. This technique showed no artifacts introduced from the
sample preparation procedure.
Epigenetic mechanisms regulating normal and malignant haematopoiesis: new therapeutic targets for clinical medicine
Authors: Bonifer Constanze , Bowen David T.
Published: February 2010

It is now well established that epigenetic phenomena and aberrant gene regulation play a major role in carcinogenesis. These include aberrant gene silencing by imposing inactive histone marks on promoters, aberrant methylation of DNA at CpG islands, and the active repression of promoters by oncoproteins. In addition, many malignant cells also show aberrant gene activation due to constitutively active signalling. The next frontier in cancer research will be to examine how, at the molecular level, small mutations that alter the regulatory phenotype of a cell give rise after a number of cell divisions to the vast deregulation phenomena seen in malignant cells. This review outlines recent insights into how normal cell differentiation in the haematopoietic system is subverted in leukaemia and it introduces the molecular players involved in this process. It also summarises the results of recent clinical trials trying to reverse aberrant epigenetic regulation by employing agents influencing global epigenetic regulators.
Soil CO2 production in upland tundra where permafrost is thawing
Authors: Lee Hanna , Schuur Edward A. G. , Vogel Jason G.
Published: February 2010

Permafrost soils store nearly half of global soil carbon (C), and therefore permafrost thawing could lead to large amounts of greenhouse gas emissions via decomposition of soil organic matter. When ice‐rich permafrost thaws, it creates a localized surface subsidence called thermokarst terrain, which changes the soil microenvironment. We used soil profile CO2 measurements to understand the response of belowground C emissions for different soil depths from upland tundra as a result of permafrost thaw and thermokarst development. We established sites in central Alaska, where permafrost thaw and thermokarst development had been monitored for the past 2 decades. Cumulative growing season CO2 production averaged for 3 years (2005–2007) ranged from 177 to 270 g CO2‐C m−2 and was lowest in the least disturbed moist acidic tundra and highest where thawing of permafrost and thermokarst was most pronounced. We were able to explain 55% of variability in growing season soil CO2 production using surface subsidence, soil temperature, and site differences. This was likely a direct effect of permafrost thaw and thermokarst development and an indirect effect of changes in microsite soil temperature and surface moisture content, which stimulated soil organic matter decomposition and root respiration. We also observed unusually high CO2 concentrations in the early growing season, which may be attributable to trapped CO2 within air pockets in the frozen soil. Taken together, these results supported the projection that permafrost thaw and thermokarst development will increase belowground carbon emissions in the upland tundra.
Identifying a rainfall event threshold triggering herbicide leaching by preferential flow
Authors: McGrath G. S. , Hinz C. , Sivapalan M. , Dressel J. , Pütz T. , Vereecken H.
Published: February 2010

How can leaching risk be assessed if the chemical flux and/or the toxicity is highly uncertain? For many strongly sorbing pesticides it is known that their transport through the unsaturated zone occurs intermittently through preferential flow, triggered by significant rainfall events. In these circumstances the timing and frequency of these rainfall events may allow quantification of leaching risk to overcome the limitations of flux prediction. In this paper we analyze the leaching behavior of bromide and two herbicides, methabenzthiazuron and ethidimuron, using data from twelve uncropped lysimeters, with high‐resolution climate data, in order to identify the rainfall controls on rapid solute leaching. A regression tree analysis suggested that a coarse‐scale fortnightly to monthly water balance was a good predictor of short‐term increases in drainage and bromide transport. Significant short‐term herbicide leaching, however, was better predicted by the occurrence of a single storm with a depth greater than a 19 mm threshold. Sampling periods where rain events exceeded this threshold accounted for between 38% and 56% of the total mass of herbicides leached during the experiment. The same threshold only accounted for between 1% and 10% of the total mass of bromide leached. On the basis of these results, we conclude that in this system, the leaching risks of strongly sorbing chemicals can be quantified by the timing and frequency of these large rainfall events. Empirical and modeling approaches are suggested to apply this frequentist approach to leaching risk assessment to other soil‐climate systems.
Surface‐subsurface flow modeling with path‐based runoff routing, boundary condition‐based coupling, and assimilation of multisource observation data
Authors: Camporese M. , Paniconi C. , Putti M. , Orlandini S.
Published: February 2010

A distributed physically based model incorporating novel approaches for the representation of surface‐subsurface processes and interactions is presented. A path‐based description of surface flow across the drainage basin is used, with several options for identifying flow directions, for separating channel cells from hillslope cells, and for representing stream channel hydraulic geometry. Lakes and other topographic depressions are identified and specially treated as part of the preprocessing procedures applied to the digital elevation data for the catchment. Threshold‐based boundary condition switching is used to partition potential (atmospheric) fluxes into actual fluxes across the land surface and changes in surface storage, thus resolving the exchange fluxes, or coupling, between the surface and subsurface modules. Nested time stepping allows smaller steps to be taken for typically faster and explicitly solved surface runoff routing, while a mesh coarsening option allows larger grid elements to be used for typically slower and more compute‐intensive subsurface flow. Sequential data assimilation schemes allow the model predictions to be updated with spatiotemporal observation data of surface and subsurface variables. These approaches are discussed in detail, and the physical and numerical behavior of the model is illustrated over catchment scales ranging from 0.0027 to 356 km2, addressing different hydrological processes and highlighting the importance of describing coupled surface‐subsurface flow.
Pumping out the atmosphere of Mars through solar wind pressure pulses
Authors: Edberg N. J. T. , Nilsson H. , Williams A. O. , Lester M. , Milan S. E. , Cowley S. W. H. , Fränz M. , Barabash S. , Futaana Y.
Published: February 2010

We study atmospheric escape from Mars during solar wind pressure pulses. During the solar minimum of 2007–08 we have observed 41 high pressure events, which are predominantly identified as corotating interaction regions (CIR) while a few are coronal mass ejections (CME), in data from the Advanced Composition Explorer (ACE) upstream of the Earth. 36 of these events are also identified using Mars Express (MEX) data at Mars. We use MEX measurements at Mars to compare the antisunward fluxes of heavy planetary ions during the passage of these pulses to the fluxes during quiet solar wind conditions. The ion fluxes are observed to increase by a factor of ∼2.5, on average. Hence, a third of the total outflow from Mars takes place during ∼15% of the time, when a solar wind pressure pulse impacts on the planet. This can have important consequences for the total time‐integrated outflow of plasma from Mars.
Amplitude and phase of nonlinear magnetospheric wave growth excited by the HAARP HF heater
Authors: Gołkowski M. , Inan U. S. , Cohen M. B. , Gibby A. R.
Published: February 2010

The High Frequency Active Auroral Research Program (HAARP) HF ionospheric heater is used to inject ELF/VLF signals into the magnetosphere to study wave‐particle interactions that lead to nonlinear amplification. HAARP‐generated whistler mode “echoes” are observed after twice crossing the equatorial plane in magnetospheric ducts. The magnetospheric paths traversed by the signals are determined to be in the range 5.06 < L < 5.19 with associated cold plasma densities of 177 cm−3 < Neq < 185 cm−3. The amplitude and phase of the echoes are observed to exhibit exponential temporal increase. A decrease in input amplitude by 14 dB is observed to yield a delay in onset of nonlinear growth by ∼1 s. Nonlinear theory of cyclotron resonant currents formed by electrons phase trapped in the potential well of the input wave is used to analyze the simultaneous evolution of amplitude and phase of the observations. The average nonlinear resonant current vector is found to rotate in relation to the input wavefields during growth, and the magnetospheric linear growth rate is estimated to be 31–45 dB/s.
Effects of substorm dynamics on magnetic signatures of the ionospheric Alfvén resonator
Authors: Parent Adrienne , Mann Ian R. , Rae I. Jonathan
Published: February 2010

Spectral resonance structures (SRS) of the ionospheric Alfvén resonator (IAR) measured by the induction magnetometer at the High Frequency Active Auroral Research Program (HAARP) ionospheric observatory during a substorm on 28 February 2006 are presented. The evolution of IAR SRS is compared to ionospheric parameters measured by the colocated Digisonde, riometer and all‐sky imager at HAARP. Initially, the magnetic IAR signatures (spectral resonance structures) exhibited an expected variation that can be attributed to typical diurnal changes in ionospheric structure. At substorm onset, the signatures disappeared because of either a suppression of resonance conditions by substorm‐related particle precipitation or enhanced power in the Pc1 spectrum that concealed continuing IAR SRS. After the substorm, the SRS reappeared; however the harmonics had shifted to lower frequencies with tighter frequency spacing. For the first time, we show that this time‐dependent behavior in IAR SRS is explained by increased F region densities resulting from electron precipitation. Similarities between observed IAR harmonic frequencies and those calculated with a model suggest that variations in F region density, especially foF2, may often dominate the evolution of IAR eigenfrequencies. This could potentially provide a mechanism for monitoring topside dynamics using IAR SRS.
Suppression of the Rhines effect and the location of vortices on Saturn
Authors: Penny A. B. , Showman A. P. , Choi D. S.
Published: February 2010

Saturn's atmosphere contains numerous vortices that reside predominantly within specific localized latitude bands. Two‐dimensional turbulence theory predicts that vortices which do form are readily destroyed as they interact with dispersive Rossby waves in a process called the “Rhines effect,” which acts to organize turbulent energy into alternating zonal flows through the interaction of Rossby waves and turbulence of similar scales. Observations show that at some latitudes, vortices are more prevalent, suggesting that Rossby waves are suppressed in these regions. Following the method applied to Jupiter by Theiss (2006), we generalize the 2‐D Rhines scale to include depth‐dependent flow with a finite deformation radius; this allows for a simple estimate of the conditions under which Rossby waves are suppressed in the cloud layer. We then compare the latitudes of known vortices to the predicted latitudes where Rossby waves may be suppressed on Saturn. We find a good correlation, suggesting that, as on Jupiter, Rossby wave suppression helps explain the prevalence of vortices at specific latitudes on Saturn.
Some Studies on Circadian Rhythm in the Culture of Omphalina Quelet sp. (Basidiomycota, Agaricales) A Mycobiont of an Unidentified Basidiolichen
Authors: Kalangutkar Jyoti , Kamat Nandkumar
Published: February 2010

This paper reports the discovery of circadian rhythm in Omphalina Quelet, in pure culture under laboratory conditions. The species was collected as a mycobiont from an unidentified basidiolichen.
Evidence for Organometallic Intermediates in Bacterial Methane Formation Involving the Nickel Coenzyme F430
Authors: Dey Mishtu , Li Xianghui , Zhou Yuzhen , Ragsdale Stephen W.
Published: February 2010

Bioorganometallic chemistry underlies the reaction mechanisms of metalloenzymes that catalyze key processes in the global carbon cycle. Metal ions that appear well suited for the formation of metal-carbon bonds are nickel, iron, and cobalt. The formation and reactivity of alkylcobalt species (methylcobalamin and adenosylcobalamin) at the active sites of B12-dependent methyltransferases and isomerases have been well studied and serve as models to guide hypothesis for how organometallic reactions occur in other systems. This review focuses on methyl-coenzyme M reductase (MCR), which is responsible for all biologically produced methane on earth. At its active site, this enzyme contains a nickel corphin (F430), which bears similarity to the cobalt corrin in cobalamin (B12). Several mechanisms have been proposed for the MCR-catalyzed reaction, and a methylnickel species is a central intermediate in all but one of these mechanisms. After introducing some important concepts of bioorganometallic chemistry and describing methanogenesis and some of the key properties of MCR, this review discusses research that has led to the generation and characterization of alkylnickel species in MCR and in model complexes related to F430. Then, the focus shifts to the reactions that these alkylnickel species can undergo both in the enzyme and in bioinspired models: protonolysis to form alkanes and thiolysis to form thioethers, including methyl-SCoM (the natural methyl donor for MCR). Throughout, results are discussed in relation to the proposed models for the MCR mechanism.
Organotins. Formation, Use, Speciation, and Toxicology
Authors: Gajda Tamás , Jancsó Attila
Published: February 2010

The speciation of organotin(IV) cations in natural waters, in sewage or in biofluids is strongly influenced by the complex formation with the available metal-binding compounds, i.e., both high and low molecular weight ligands of biological and environmental interest. The primary intention of this chapter is to discuss the aquatic solution chemistry of organotin cations and their complexes formed with low and high molecular weight bioligands. Besides, some synthetic aspects, applications and sources of organotin pollution, their destinations in the environment, and toxicology will be also shortly discussed.
Toxicology of Alkylmercury Compounds
Authors: Aschner* Michael , Onishchenko Natalia , Ceccatelli Sandra
Published: February 2010

Methylmercury is a global pollutant and potent neurotoxin whose abundance in the food chain mandates additional studies on the consequences and mechanisms of its toxicity to the central nervous system. Formulation of our new hypotheses was predicated on our appreciation for (a) the remarkable affinity of mercurials for the anionic form of sulfhydryl (-SH) groups, and (b) the essential role of thiols in protein biochemistry. The present chapter addresses pathways to human exposure of various mercury compounds, highlighting their neurotoxicity and potential involvement in neurotoxic injury and neurodegenerative changes, both in the developing and senescent brain. Mechanisms that trigger these effects are discussed in detail.
Methylated Metal(loid) Species in Humans
Authors: Hirner Alfred V. , Rettenmeier Albert W.
Published: February 2010

While the metal(loid)s arsenic, bismuth, and selenium (probably also tellurium) have been shown to be enzymatically methylated in the human body, this has not yet been demonstrated for antimony, cadmium, germanium, indium, lead, mercury, thallium, and tin, although the latter elements can be biomethylated in the environment. Methylated metal(loid)s exhibit increased mobility, thus leading to a more efficient metal(loid) transport within the body and, in particular, opening chances for passing membrane barriers (blood-brain barrier, placental barrier). As a consequence human health may be affected. In this review, relevant data from the literature are compiled, and are discussed with respect to the evaluation of assumed and proven health effects caused by alkylated metal(loid) species.
Structure control of organized mesoporous TiO2 films templated by graft copolymers for dye-sensitized solar cells
Authors: Ahn Sung Hoon , Koh Joo Hwan , Seo Jin Ah , Kim Jong Hak
Published: February 2010

Randomly microphase-separated graft copolymers are self-reorganized to exhibit a micellar structure upon tuning the solvent affinity. These are used as a structure-directing agent for organized mesoporous TiO2 films, leading to enhanced performance of dye-sensitized solar cells.
The power of the weak: recognition of ion pairs in water using a simple array sensor
Authors: Liu Yuan-li , Palacios Manuel A. , Anzenbacher Pavel
Published: February 2010

Thirty-five different ion pairs are recognized by a sensor array consisting of supramolecular hydrogel and six off-the-shelf pH indicators at pH = 5–9. Such recognition efficiency (6 : 35) with ≥93% classification accuracy is rare.
Commonly used tag combinations for tandem affinity purification
Authors: Li Yifeng
Published: February 2010

TAP (tandem affinity purification) allows rapid and clean isolation of a tagged protein along with its interacting partners from cell lysates. Initially developed in yeast, the TAP method has subsequently been adapted to other cells and organisms. In combination with MS analysis, this method has become an indispensable tool for systematic identification of target‐associated protein complexes. The key feature of TAP is the use of a dual‐affinity tag, which is fused to the protein of interest. The original TAP tag consisted of two IgG‐binding units of Protein A of Staphylococcus aureus and the calmodulin‐binding peptide. As the technique has been widely exploited, a number of alternative TAP tags based on other affinity handles have been developed. The present review gives an overview of the various tag combinations for TAP with a highlight on those alternatives that result in improved yields or unique features. The information provided should assist in the selection and development of TAP tags for specific applications.
Sealed operation of a rf driven ion source for a compact neutron generator to be used for associated particle imaging
Authors: Wu Y. , Hurley J. P. , Ji Q. , Kwan J. W. , Leung K. N.
Published: February 2010

We present the recent development of a prototype compact neutron generator to be used in conjunction with the method of associated particle imaging for the purpose of active neutron interrogation. In this paper, the performance and device specifications of these compact generators that employ rf driven ion sources will be discussed. Initial measurements of the generator performance include a beam spot size of 1 mm in diameter and a neutron yield of 2×105 n/s with air cooling.
Electron cyclotron resonance plasma photos
Authors: Rácz R. , Biri S. , Pálinkás J.
Published: February 2010

In order to observe and study systematically the plasma of electron cyclotron resonance (ECR) ion sources (ECRIS) we made a high number of high-resolution visible light plasma photos and movies in the ATOMKI ECRIS Laboratory. This required building the ECR ion source into an open ECR plasma device, temporarily. An 8MP digital camera was used to record photos of plasmas made from Ne, Ar, and Kr gases and from their mixtures. We studied and recorded the effect of ion source setting parameters (gas pressure, gas composition, magnetic field, and microwave power) to the shape, color, and structure of the plasma. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas.
Production of highly charged ion beams with SECRAL
Authors: Sun L. T. , Zhao H. W. , Lu W. , Zhang X. Z. , Feng Y. C. , Li J. Y. , Cao Y. , Guo X. H. , Ma H. Y. , Zhao H. Y. , Shang Y. , Ma B. H. , Wang H. , Li X. X. , Jin T. , Xie D. Z.
Published: February 2010

Superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is an all-superconducting-magnet electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged ion beams to meet the requirements of the Heavy Ion Research Facility in Lanzhou (HIRFL). To further enhance the performance of SECRAL, an aluminum chamber has been installed inside a 1.5 mm thick Ta liner used for the reduction of x-ray irradiation at the high voltage insulator. With double-frequency (18+14.5 GHz) heating and at maximum total microwave power of 2.0 kW, SECRAL has successfully produced quite a few very highly charged Xe ion beams, such as 10 e μA of Xe37+, 1 e μA of Xe43+, and 0.16 e μA of Ne-like Xe44+. To further explore the capability of the SECRAL in the production of highly charged heavy metal ion beams, a first test run on bismuth has been carried out recently. The main goal is to produce an intense Bi31+ beam for HIRFL accelerator and to have a feel how well the SECRAL can do in the production of very highly charged Bi beams. During the test, though at microwave power less than 3 kW, more than 150 e μA of Bi31+, 22 e μA of Bi41+, and 1.5 e μA of Bi50+ have been produced. All of these results have again demonstrated the great capability of the SECRAL source. This article will present the detailed results and brief discussions to the production of highly charged ion beams with SECRAL.
Charge state breeding for the acceleration of radioactive ions at TRIUMF
Authors: Ames F. , Baartman R. , Bricault P. , Jayamanna K. , Lamy T. , McDonald M.
Published: February 2010

A 14.5 GHz electron cyclotron resonance ion source (PHOENIX from Pantechnik) has been set up at the Isotope Separation and ACceleration (ISAC) facility at TRIUMF for the charge state breeding of radioactive ions. After extensive testing and optimization on a test bench it has been moved on-line and put into operation. During a first test in 2008 a beam of R80b14+ was successfully created from R80b1+ and accelerated by the ISAC postaccelerator. Further tests with different stable and radioactive isotopes from the ISAC on-line sources and from a test source with stable Cs have been carried out. Until now an efficiency of 1.4% for C124s20+ has been obtained.
The study of helicon plasma source
Authors: Miao Ting-Ting , Zhao Hong-Wei , Liu Zhan-Wen , Shang Yong , Sun Liang-Ting , Zhang Xue-Zhen , Zhao Huan-Yu
Published: February 2010

Helicon plasma source is known as efficient generator of uniform and high density plasma. A helicon plasma source was developed for investigation of plasma neutralization and plasma lens in the Institute of Modern Physics in China. In this paper, the characteristics of helicon plasma have been studied by using Langmuir four-probe and a high argon plasma density up to 3.9×1013 cm−3 have been achieved with the Nagoya type III antenna at the conditions of the magnetic intensity of 200 G, working gas pressure of 2.8×10−3 Pa, and rf power of 1200 W with a frequency of 27.12 MHz. In the experiment, the important phenomena have been found: for a given magnetic induction intensity, the plasma density became greater with the increase in rf power and tended to saturation, and the helicon mode appeared at the rf power between 200 and 400 W.
Measurements of transverse ion beam emittance generated by high current ion sources at the GSI test injector facility HOSTI
Authors: Adonin A. , Hollinger R. , Spädtke P.
Published: February 2010

The first emittance measurements with a new test injector facility (HOSTI) at GSI, designed for optimization of high current beam injection scheme, are discussed. The emittance of the ion beam (88 kV, Ar1+ ions) was investigated as a function of various parameters related to the ion source, extraction, and postacceleration systems and the optimum parameters for future low energy beam transport line are concluded. The preliminary results of the emittance measurements with superconducting solenoid are presented. The influence of the focusing strength as well as the longitudinal field shape of the solenoid on the beam emittance is described.