bluuebunny/crossref_metadata_2025 huggingface dataset:
Schottky junction/ohmic contact behavior of a nanoporous TiO2thin film photoanode in contact with redox electrolyte solutions
Authors: Kaneko Masao , Ueno Hirohito , Nemoto Junichi
Published: March 2011

The nature and photoelectrochemical reactivity of nanoporous semiconductor electrodes have attracted a great deal of attention. Nanostructured materials have promising capabilities applicable for the construction of various photonic and electronic devices. In this paper, a mesoporous TiO2thin film photoanode was soaked in an aqueous methanol solution using an O2-reducing Pt-based cathode in contact with atmospheric air on the back side. It was shown from distinct photocurrents in the cyclic voltammogram (CV) that the nanosurface of the mesoporous n-TiO2film forms a Schottky junction with water containing a strong electron donor such as methanol. Formation of a Schottky junction (liquid junction) was also proved by Mott–Schottky plots at the mesoporous TiO2thin film photoanode, and the thickness of the space charge layer was estimated to be very thin, i.e., only 3.1 nm at −0.1 V vs Ag/AgCl. On the other hand, the presence of [Fe(CN)6]4−and the absence of methanol brought about ohmic contact behavior on the TiO2film and exhibited reversible redox waves in the dark due to the [Fe(CN)6]4−/3−couple. Further studies showed that multiple Schottky junctions/ohmic contact behavior inducing simultaneously both photocurrent and overlapped reversible redox waves was found in the CV of a nanoporous TiO2photoanode soaked in an aqueous redox electrolyte solution containing methanol and [Fe(CN)6]4−. That is, the TiO2nanosurface responds to [Fe(CN)6]4−to give ohmic redox waves overlapped simultaneously with photocurrents due to the Schottky junction. Additionally, a second step photocurrent generation was observed in the presence of both MeOH and [Fe(CN)6]4−around the redox potential of the iron complex. It was suggested that the iron complex forms a second Schottky junction for which the flat band potential (Efb) lies near the redox potential of the iron complex.
Successful Efavirenz Dose Reduction Guided by Therapeutic Drug Monitoring
Authors: Mello Aurélie Fayet , Buclin Thierry , Decosterd Laurent A , Delhumeau Cécile , di Iulio Julia , Fleurent Alessandra , Schneider Marie-Paule , Cavassini Matthias , Telenti Amalio , Hirschel Bernard , Calmy Alexandra
Published: March 2011

Background

There are potential benefits to individualizing dosage in patients treated with efavirenz (EFV). We tested a simplified algorithm based on a Bayesian pharmacokinetic approach for guiding dose reduction in patients with EFV concentrations above the 75th percentile (P75) with documented virological efficacy.

Methods

We designed a prospective, open-label, multi-centre study. All consenting participants with EFV concentrations above P75 on standard dosage were included in a dose-reduction cycle. Primary end point was the number of patients who reached plasma concentrations within target (1,000–4,000 ng/ml) after, at most, two cycles of dose reduction at 3 and 6 months. CYP2B6 genetic characterization was performed.

Results

Seventy-two patients were screened and 13 ful-filled selection criteria. These patients, with undetectable viraemia on a stable 600 mg EFV-based regimen, had a median (interquartile range) EFV plasma level of 8,112 ng/ml (5,993–10,278) at baseline; 38% (between P75 and P95) qualified for a 400 mg EFV dose, and 62% (above P95) qualified for a 200 mg EFV dose. After one to two dose-reduction cycles, all patients reached targets for EFV plasma concentration at 24 weeks. The predictive dose reduction based on genetic profile differed from dose reduction according to therapeutic drug monitoring (TDM) in three patients. All patients maintained viral suppression at 6 months.

Conclusions

A standardized TDM-guided EFV dose-reduction strategy over a 24-week period was successful, safe and yielded EFV plasma concentrations within the recommended therapeutic range. In addition to improving neuropsychiatric tolerability, EFV dose reduction has the potential to substantially decrease treatment cost.
Toronto Psoriatic Arthritis Screening (ToPAS) Questionnaire: A Report from the GRAPPA 2009 Annual Meeting
Authors: CHANDRAN VINOD , GLADMAN DAFNA D.
Published: March 2011

The Toronto Psoriatic Arthritis Screening questionnaire (ToPAS) was developed as a tool to screen for psoriatic arthritis (PsA) in patients with psoriasis as well as in the general population. Thus, it differs from PsA-specific screening tools and may be used to screen for PsA in epidemiologic and family investigations. In a presentation at the 2009 annual meeting of GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) in Stockholm, Sweden, the authors described the development, testing, and validation of the ToPAS tool. Results of a comparison of the ToPAS questionnaire with the Psoriatic Arthritis Screening and Evaluation (PASE) questionnaire were also presented. Modification and further validation of the ToPAS are under way.
L'étude du lien entre cycle et saisonnalité sur un marché immobilier résidentiel. Le cas de l'habitat ancien à Bordeaux
Authors: Faye Benoit , Le Fur Éric
Published: March 2011

La saisonnalité du marché immobilier est un phénomène reconnu bien que peu étudié, notamment dans sa relation avec le cycle immobilier. En utilisant une base de données sur les transactions immobilières de la ville de Bordeaux, nous explorons ici les liens entre les mouvements du cycle et les modifications de la saisonnalité des prix, pour l’ensemble du marché et par type de biens. Cette approche descriptive permet de poser les bases d’une modélisation plus pertinente des séries de prix.
Enjeux politiques et sociaux de la culture chevaleresque au XVI e siècle : les prologues de chansons de geste imprimées
Authors: Deruelle Benjamin
Published: March 2011

Résumé Alors que la première modernité est traditionnellement présentée comme le « crépuscule de la chevalerie », le nombre et la diffusion des romans de chevalerie n’ont jamais été aussi importants. Paradoxalement, alors que les liens entre histoire et politique ont été l’objet de l’intérêt des historiens ; celui entre littérature et politique demeure peu étudié. Pourtant, les littéraires, telles qu’Emmanuelle Poulain Gautret et Élisabeth Gaucher, ont récemment démontré la dimension politique de la littérature chevaleresque de la fin du Moyen Âge. Cette littérature connaît depuis ses origines des mouvements de réécritures incessants qui lui permettent de survivre tout en s’adaptant aux évolutions de la société. Les traductions en prose et le passage du manuscrit à l’imprimé sont l’occasion, au cours du xv e siècle et de la première moitié du xvi e siècle, d’une redécouverte de la culture chevaleresque avec les yeux de la Renaissance. L’étude des prologues des romans issus des anciennes chansons de geste permet de saisir quels sont les pratiques, les fonctions et les enjeux de la transmission de la culture chevaleresque dans une noblesse confrontée à la genèse de l’État moderne, à la concurrence de la Robe et de la bourgeoisie, et aux critiques de plus en plus acerbes de sa position de domination.
Le dégoût dans le travail d'assistance aux soins personnels, s'en défendre mais pas trop
Authors: Marché-Paillé Anne
Published: March 2011

Résumé Le travail d’assistance aux soins personnels des personnes âgées en hébergement collectif est socialement assimilé au sale boulot, à la part ingrate du travail des soins infirmiers. Il est délégué à des femmes et des hommes qui ont à se défendre de l’insupportable du dégoût et de la menace éthique qu’il représente pour le travail bien fait. L’article examine les stratégies défensives mises en place pour résister au dégoût et subvertir la souffrance en plaisir dans une clinique du toucher et de la conversation qui fait advenir les résidents en sujets désirants. Néanmoins, le dégoût ne peut être totalement suspendu, car il contient une efficace dont les préposées ne peuvent se passer dans les aspects hygiéniste, compassionnel et coopératif de leur travail. Enfin, le rapport entre travail et dégoût revêt ici une forme de courage moral qui pourrait se révéler caractéristique du travail de care.
Practical limitations and applications of short dead time surface NMR
Authors: Walsh David O. , Grunewald Elliot , Turner Peter , Hinnell Andrew , Ferre Paul
Published: March 2011

There is increasing interest in the unique measurement capabilities of nuclear magnetic resonance (NMR) for hydrologic applications. In particular, the ability to quantify water content (both bound and free) and to infer the permeability distribution are critical to hydrologists. As the method has gained in acceptance, there has been growing interest in extending its range to near‐surface and vadose zone applications and to measurement in finer grained and magnetic soils. All of these applications require improved resolution of early‐time signals, which requires shorter measurement dead times. This paper analyses three physical/electrical processes that limit the minimum achievable measurement dead times in surface NMR applications: 1) inherent characteristics of electromechanical and semiconductor switching devices, 2) the effective bandwidth of the receiver and signal processing chain, 3) transient signals associated with induced eddy currents in the ground. We then describe two applications of surface NMR that rely on reduced measurement dead time: detection and characterization of fast decaying NMR signals in silt and clay and the detection of fast decaying NMR signals in magnetic geology.
Independent Association Between Preoperative Cognitive Status and Discharge Location After Cardiac Surgery
Authors: Harrington Mary Beth , Kraft Malissa , Grande Laura J. , Rudolph James L.
Published: March 2011

Background

Among cardiac surgery patients, those with impaired cognitive status before surgery may have longer postoperative stays than do patients with normal status and may require additional care upon discharge.

Objectives

To determine if preoperative scores on a screening measure for cognitive status (the Clock-in-the-Box), were associated with postoperative length of stay and discharge to a location other than home in patients who had cardiac surgery.

Methods

A total of 181 consecutive patients scheduled for cardiac surgery at a single site were administered the Clock-in-the-Box as part of the preoperative evaluation. Scores on the Clock-in-the-Box tool, demographic and operative information, postoperative length of stay, and discharge location were collected retrospectively from medical records.

Results

The mean age of the patients was 68.1 years (SD, 0.7), and 99% were men. Mean postoperative length of stay was 10.5 days (SD, 8.2), and 35 patients (19%) were discharged to a facility. Scores on the Clock-in-the-Box assessment were not associated with postoperative length of stay. Increasing age, living alone before surgery, and duration of cardiopulmonary bypass were associated with discharge to a facility and were used as covariates in adjusted analyses. After adjustment, better preoperative cognitive status reduced the risk of being discharged to a facility (adjusted relative risk, 0.93; 95% confidence interval, 0.89–0.98) after cardiac surgery.

Conclusions

Cognitive screening before cardiac surgery can identify patients with impaired cognitive status who are less likely than patients with normal cognitive status to return home after cardiac surgery.
Emergency Subtotal Colectomy in a Jehovah’s Witness With Massive Lower Gastrointestinal Bleeding: Challenges Encountered and Lessons Learned
Authors: Raman Shankar R. , Parithivel Vellore S. , Cosgrove John M.
Published: March 2011

A 66-year-old woman who was a Jehovah’s Witness had massive lower gastrointestinal bleeding and subsequent hypovolemic shock, necessitating a subtotal colectomy. During the postoperative period, her hemoglobin level decreased to a low of 2.6 g/dL, prolonging her dependence on mechanical ventilation. Prudent perioperative care resulted in a successful outcome. Blood-conserving techniques are indispensable in the management of Jehovah’s Witnesses who have massive blood loss. Maximizing oxygen transport, minimizing blood loss, using a cell saver when permissible, providing optimal ventilatory support, performing tracheostomy early if prolonged mechanical ventilation is expected, and augmenting hemoglobin production with administration of iron and erythropoietin are techniques that can facilitate successful outcome in patients who refuse blood transfusion.
The Airway Antigen Sampling System: Respiratory M Cells as an Alternative Gateway for Inhaled Antigens
Authors: Kim Dong-Young , Sato Ayuko , Fukuyama Satoshi , Sagara Hiroshi , Nagatake Takahiro , Kong Il Gyu , Goda Kaoru , Nochi Tomonori , Kunisawa Jun , Sato Shintaro , Yokota Yoshifumi , Lee Chul Hee , Kiyono Hiroshi
Published: March 2011

In this study, we demonstrated a new airway Ag sampling site by analyzing tissue sections of the murine nasal passages. We revealed the presence of respiratory M cells, which had the ability to take up OVA and recombinant Salmonella typhimurium expressing GFP, in the turbinates covered with single-layer epithelium. These M cells were also capable of taking up respiratory pathogen group A Streptococcus after nasal challenge. Inhibitor of DNA binding/differentiation 2 (Id2)-deficient mice, which are deficient in lymphoid tissues, including nasopharynx-associated lymphoid tissue, had a similar frequency of M cell clusters in their nasal epithelia to that of their littermates, Id2+/− mice. The titers of Ag-specific Abs were as high in Id2−/− mice as in Id2+/− mice after nasal immunization with recombinant Salmonella-ToxC or group A Streptococcus, indicating that respiratory M cells were capable of sampling inhaled bacterial Ag to initiate an Ag-specific immune response. Taken together, these findings suggest that respiratory M cells act as a nasopharynx-associated lymphoid tissue-independent alternative gateway for Ag sampling and subsequent induction of Ag-specific immune responses in the upper respiratory tract.
Platelets Participate in Synovitis via Cox-1–Dependent Synthesis of Prostacyclin Independently of Microparticle Generation
Authors: Boilard Eric , Larabee Katherine , Shnayder Ruslan , Jacobs Kathleen , Farndale Richard W. , Ware Jerry , Lee David M.
Published: March 2011

In addition to the well-described role of platelets in thrombosis, a growing body of evidence implicates platelets in diverse inflammatory responses. We recently showed platelets can contribute to the pathophysiology of inflammatory arthritis via IL-1– containing microparticles. In this study, we demonstrate that platelets, and not platelet microparticles, actively contribute to synovitis via production of proinflammatory prostacyclin in an autoimmune arthritis model. Using both genetic and pharmacologic approaches, we establish that paracrine production of prostacyclin proceeds in the absence of cyclooxygenase-2. Furthermore, we also demonstrate that prostacyclin generation can arise via transcellular collaboration between platelets and fibroblast-like synoviocytes. In addition to shedding light on an unappreciated pathway of lipid synthesis in arthritis, we further delineate a novel effector activity by which platelets can contribute to inflammatory disease.
Alcohol Suppresses the Granulopoietic Response to Pulmonary Streptococcus pneumoniae Infection with Enhancement of STAT3 Signaling
Authors: Siggins Robert W. , Melvan John N. , Welsh David A. , Bagby Gregory J. , Nelson Steve , Zhang Ping
Published: March 2011

Enhanced granulopoietic activity is crucial for host defense against bacterial pneumonia. Alcohol impairs this response. The underlying mechanisms remain obscure. G-CSF produced by infected lung tissue plays a key role in stimulating bone marrow granulopoiesis. This study investigated the effects of alcohol on G-CSF signaling in the regulation of marrow myeloid progenitor cell proliferation in mice with Streptococcus pneumoniae pneumonia. Chronic alcohol consumption plus acute alcohol intoxication suppressed the increase in blood granulocyte counts following intrapulmonary challenge with S. pneumoniae. This suppression was associated with a significant decrease in bone marrow granulopoietic progenitor cell proliferation. Alcohol treatment significantly enhanced STAT3 phosphorylation in bone marrow cells of animals challenged with S. pneumoniae. In vitro experiments showed that G-CSF–induced activation of STAT3–p27Kip1 pathway in murine myeloid progenitor cell line 32D-G-CSFR cells was markedly enhanced by alcohol exposure. Alcohol dose dependently inhibited G-CSF–stimulated 32D-G-CSFR cell proliferation. This impairment of myeloid progenitor cell proliferation was not attenuated by inhibition of alcohol metabolism through either the alcohol dehydrogenase pathway or the cytochrome P450 system. These data suggest that alcohol enhances G-CSF–associated STAT3–p27Kip1 signaling, which impairs granulopoietic progenitor cell proliferation by inducing cell cycling arrest and facilitating their terminal differentiation during the granulopoietic response to pulmonary infection.
New Thoughts on Thought Disorders in Parkinson's Disease: Review of Current Research Strategies and Challenges
Authors: Goldman Jennifer G.
Published: March 2011

Psychosis is a frequent nonmotor complication in Parkinson's disease (PD), characterized by a broad phenomenology and likely due to a variety of intrinsic (i.e., PD-related) and extrinsic factors. Safe and effective therapies are greatly needed as PD psychosis contributes significantly to morbidity, mortality, nursing home placement, and quality of life. Novel research strategies focused on understanding the pharmacology and pathophysiology of PD psychosis, utilizing translational research including animal models, genetics, and neuroimaging, and even looking beyond the dopamine system may further therapeutic advances. This review discusses new research strategies regarding the neurobiology and treatment of PD psychosis and several associated challenges.
Increased Left Ventricular Stiffness Impairs Exercise Capacity in Patients with Heart Failure Symptoms Despite Normal Left Ventricular Ejection Fraction
Authors: Sinning David , Kasner Mario , Westermann Dirk , Schulze Karsten , Schultheiss Heinz-Peter , Tschöpe Carsten
Published: March 2011

Aims. Several mechanisms can be involved in the development of exercise intolerance in patients with heart failure despite normal left ventricular ejection fraction (HFNEF) and may include impairment of left ventricular (LV) stiffness. We therefore investigated the influence of LV stiffness, determined by pressure-volume loop analysis obtained by conductance catheterization, on exercise capacity in HFNEF.Methods and Results. 27 HFNEF patients who showed LV diastolic dysfunction in pressure-volume (PV) loop analysis performed symptom-limited cardiopulmonary exercise testing (CPET) and were compared with 12 patients who did not show diastolic dysfunction in PV loop analysis. HFNEF patients revealed a lower peak performance (), breathing reserve (), and ventilation equivalent for carbon dioxide production at rest (). LV stiffness correlated with peak oxygen uptake (, ), peak oxygen uptake at ventilatory threshold (, ), and ventilation equivalent for carbon dioxide production at ventilatory threshold (, ).Conclusions. CPET parameters such as peak oxygen uptake, peak oxygen uptake at ventilatory threshold, and ventilation equivalent for carbon dioxide production at ventilatory threshold correlate with LV stiffness. Increased LV stiffness impairs exercise capacity in HFNEF.
Seismograms for historic Canadian earthquakes: the 29 May 1940 Richardson Mountains, Yukon earthquake
Authors: Cassidy J F , Bent A L
Published: March 2011

This paper is one in a series of reports designed to catalog the Geological Survey of Canada's (GSC) collection of seismograms for historical Canadian earthquakes. The data set has been assembled by past and present seismologists at the GSC. The seismogram
collection for the May 1940 Richardson Mountains earthquake consists of 89 records from 34 seismograph stations. Of these, 58 seismograms from 19 stations have been digitized. To assist those who may study this earthquake in the future, this report describes the seismograms in the collection and
inclicates which record segments have been digitizecl. The digital data files may be obtainecl from the GSC. We also summarize magnitude calculations and first motion polarities for all stations utilizecl in the cletailecl stucly of this earthquake by Cassidy and Beni,
[1993].
Intensity report of the November 25, 1988 Saguenay, Quebec, earthquake
Authors: Cajka M G , Drysdale J A
Published: March 2011

On Friday November 25, 1988 the largest earthquake in eastern North America in 53 years occurred 35 km south of Chicoutimi, Québec and 75 km north of the Charlevoix-Kamouraska earthquake zone. This earthquake, referred to as the Saguenay earthquake, was
located in a relatively aseismic region, had a calculated magnitude of 5.9 mb, 6.5 MN, and a depth of 29 km. lt was characterized by a single foreshock, relatively minor aftershock activity, and a large amount of high frequency energy. The Geological Survey of Canada distributed about 2400
questionnaires to rural postmasters in Quebec, Ontario, the Maritimes and Newfoundland to determine intensity distribution. Response rate was estimated to be about 75%. Supplementary information was obtained from technical reports and local newspapers. The Canadian data were combined with
similar data collected by the National Earthquake Information Service in the United States and used to produce an isoseismal map. The Saguenay earthquake was felt with maximum intensity MM VIII, but more typically MM VII, in the Chicoutimi-Jonquière-La Baie area, was felt strongly by most
people within 500 km, was felt by many within 1000 km and was perceptible by some people, under special circumstances, beyond 1000 km. Damage in the sparsely populated epicentral area was modest, limited to cracked or fallen unreinforced masonry walls and a few minor landslides. Damage outside the
epicentral area was correlated with underlying unconsolidated deposits. The total felt area of over 3.5 million km2 is consistent with the large amount of high frequency energy and approaches that of the M6.5 Charlevoix-Kamouraska earthquake in 1925.
Noradrenergic Modulation of Light-Driven Egr-1 Expression in the Adult Visual Cortex
Authors: Tremere Liisa A.
Published: March 2011

Noradrenaline has been shown to modulate sensory driven responses in the primary visual cortex (V1) of a number of vertebrate species. Moreover, this neurotransmitter has been postulated to bridge neuronal activation to genomic responses in order to instruct cells in long-lasting changes in neuronal performance. Here we show that local noradrenergic receptor activation in V1 is required for experience-regulated gene expression in the mouse V1. More specifically, we demonstrate that noradrenaline used locally within V1 mediates the light-driven gene expression of egr-1, an immediate early gene implicated as a mediator of neuronal plasticity. Visually-driven egr-1 expression largely depends on the α-adrenergic receptor subtype, with a lesser involvement of the β-subtype. Our findings suggest that noradrenergic transmission regulates plasticity associated gene expression in V1 of awake mice and is well positioned to broadly integrate experience-dependent changes at the cell's membrane and the genomic machinery in neurons.
Characteristics of wood wastes in British Columbia and their potential suitability as soil amendments and seedling growth media
Authors: Venner Kirsty , Preston Caroline , Prescott Cindy
Published: March 2011

Venner, K. H, Preston, C. M. and Prescott, C. E. 2011. Characteristics of wood wastes in British Columbia and their potential suitability as soil amendments and seedling growth media. Can. J. Soil Sci. 91: 95–106. In British Columbia, alternative uses for poor-quality wood-waste fines (approximately 50 mm or less) are being sought to replace traditional methods of disposal, including landfilling and burning without energy recovery. As a complement to associated field trials to assess the potential suitability of woody wastes as soil amendments, we determined chemical, physical and spectroscopic characteristics of a variety of wood wastes, co-composts and wood chips and carried out a plant (Betula papyrifera) bioassay. Chemical properties and 13C NMR spectra indicated similarity to other woody wastes, and suitability for site rehabilitation if applied under conditions to avoid excessive leachate. Seedlings grew poorly in the wood waste materials (final height <4 cm), except for co-composts prepared with municipal biosolids (final height 93 cm). Seedlings also grew poorly in wood chips unless fertilizer was added, indicating that nutrient deficiencies were the primary cause of the poor growth in wood chips. Even with nutrient addition, seedling growth was low in the finest wood chips (<10 mm), probably as a consequence of retention of excessive moisture. This problem could be overcome by applying larger particles or by incorporating the wood chips into soil rather than leaving them as a surface mulch. In conjunction with results from field trials, these results support the application of woody wastes for site rehabilitation, where in situ mixing with mineral soil should reduce bulk density and improve water-holding capacity, and fertilization can compensate for N immobilization by wastes with high C:N ratios.
Predicting soil organic carbon and total nitrogen using mid- and near-infrared spectra for Brookston clay loam soil in Southwestern Ontario, Canada
Authors: Xie H. T. , Yang X. M. , Drury C. F. , Yang J. Y. , Zhang X. D.
Published: March 2011

Xie, H. T., Yang, X. M., Drury, C. F., Yang, J. Y. and Zhang, X. D. 2011. Predicting soil organic carbon and total nitrogen using mid- and near-infrared spectra for Brookston clay loam soil in Southwestern Ontario, Canada. Can. J. Soil Sci. 91: 53–63. Mid-infrared (MIR) and near-infrared (NIR) spectroscopy of soils have been tested to estimate soil organic carbon (SOC) and total N (TN) concentrations at local, regional and national scales. However, these methods have rarely been used to assess SOC and TN concentrations of the same soil under different management practices. The objective of this study was to determine if models developed from infrared spectra of Brookston clay loam soils under different management practices could be used to estimate SOC, and TN concentrations and the C:N ratio. Soils used for model calibration included 217 samples from a long-term fertilization and crop rotation study and a long-term compost study, whereas 78 soil samples from a long-term tillage study on the same soil type were used for model validation. Soil organic carbon and TN concentrations of all samples were also analyzed using dry combustion techniques. Soil samples were scanned from 4000 to 400 cm−1 (2500–25 000 nm) for MIR spectra and from 8000 to 4000 cm−1 (1250–2500 nm) for NIR spectra. Partial least squares regression (PLSR) analysis was used for the calibration dataset to build prediction models for SOC, TN and C:N ratio. The SOC and TN concentrations determined using dry combustion techniques were compared with the prediction from the models using the calibration datasets. The predictions of SOC and TN concentrations by the PLSR method using infrared spectra were statistically sound, with high coefficient of determination with the calibration dataset (R2cal, SOCMIR=0.99 and SOCNIR=0.97, TNMIR=0.98 and TNNIR=0.97) and the validation dataset (R2val, SOCMIR=0.96 and SOCNIR=0.95, TNMIR=0.96 and TNNIR=0.95) and low root mean square error (RMSEPcal, SOCMIR=0.93 and SOCNIR=1.60, TNMIR=0.08 and TNNIR=0.12; RMSEPval, SOCMIR=1.40 and SOCNIR=1.75, TNMIR=0.11 and TNNIR=0.12). The predictions of SOC and TN concentrations in the 5 to 30 cm depth were better than the predictions for either the surface (0 to 5 cm) soils or for soils from lower depths (>30 cm). The models could be used as an alternative method for determining SOC and TN concentrations of Brookston clay loam soils; however, larger sample populations and improved model algorithms could further improve predictions.
Phosphorus use efficiency and long-term trends in soil available phosphorus in wheat production systems with and without nitrogen fertilizer
Authors: Selles F. , Campbell C. A. , Zentner R. P. , Curtin D. , James D. C. , Basnyat P.
Published: March 2011

Selles, F., Campbell, C. A., Zentner, R. P., Curtin, D., James, D. C. and Basnyat, P. 2011. Phosphorus use efficiency and long-term trends in soil available phosphorus in wheat production systems with and without nitrogen fertilizer. Can. J. Soil Sci. 91: 39–52. Efficient use of phosphorus (P) in crop production is important for economic and environmental reasons, and to prolong the life of a limited resource. Short-term studies often show low recovery of fertilizer P, but P use efficiency may be underestimated because the value of residual P in the soil is ignored. Our objective was to determine fertilizer P use efficiency in two wheat production systems [continuous wheat (CW) and a 3-yr rotation of summer fallow-wheat-wheat (FWW)] using data from a 39-yr study (1967–2005) at Swift Current, SK. Each rotation received either P only (P) or nitrogen plus P (NP) fertilizer. Annual grain P removal was monitored (all straw was returned to the soil) and changes in soil available P (0- to 15-cm layer) were measured by the Olsen bicarbonate method. In 1993, subplots which received no additional P were established to evaluate the residual effect of P fertilizer applied in the preceding 27 yr. Where P was applied each year, grain P removal averaged 54 to 78% of fertilizer P, with values as high as 65 to 109% in 1994 to 2005, the period of lowest water deficit. The P-only treatments removed 13% less P in grain, on average, than NP treatments. In the P-nly systems, Olsen P content increased linearly with time, but in the NP systems it reached a maximum after 20–22 yr and then stabilized. The cumulative P balance (fertilizer P minus P removed in grain) accounted for 60% of the variability in Olsen P accumulation over the course of the experiment. In CW, Olsen P content increased by 0.15 kg ha−1 for each kg ha−1 of P added in excess of crop removal. The rate of Olsen P accumulation was greater (0.20 kg ha−1 for each kg ha−1 of excess fertilizer P) in the FWW rotation possibly due to P mineralization during the summer fallow year. When P was withheld between 1994 and 2005, total grain production in the CW rotation was reduced slightly (by 10%), but there was no significant effect on FWW. Crop P removal (1967–2005) where P was withheld in the final 12 yr was equivalent to 105 and 90% of fertilizer P added to the NP and P-only systems, respectively. We concluded that residual P in prairie soils is retained in forms that are available to plants; wheat crops may therefore recover close to 100% of applied fertilizer P given sufficient time.
Estimating the impact of manure nitrogen losses on total nitrogen application on agricultural land in Canada
Authors: Yang J. Y. , Huffman E. C. , Drury C. F. , Yang X. M. , De Jong R.
Published: March 2011

Yang, J. Y., Huffman, E. C., Drury, C. F., Yang, X. M. and De Jong, R. 2011. Estimating the impact of manure nitrogen losses on total nitrogen application on agricultural land in Canada. Can. J. Soil Sci. 91: 107–122. About 1 million tonnes (1 Tg=1012 g) of livestock manure N are applied to farmland in Canada each year. Comprehensive information on manure N production and losses from manure during on-farm storage, handling and field application is scarce, especially at a regional scale. However, manure N losses during storage and land application are of considerable concern with respect to nitrogen use efficiency and environmental pollution of air, soil and water. In this paper, manure N production, manure N losses during storage and land application and manure N mineralization from organic manure and the resultant manure N available for annual crops were estimated using the Census of Agriculture database, Farm Environmental Management Survey data and manure N loss factors obtained from the literature. A database of fertilizer N application rates for field crops was developed at the regional scale based on recommendations provided in agronomic extension bulletins and fertilizer N sales. Fertilizer N and available manure N (i.e., total manure N produced minus N losses plus N mineralized from manure applied in previous years) were allocated to each of 24 crops at the regional scale from 1981 to 2006.

The amount of manure N produced in Canada increased by 18.7% from 0.928 Tg in 1981 to 1.102 Tg in 2006. We estimated that 35.6% of the manure N produced was immediately available to crops, 25.6% was lost during storage and land application and 38.8% was carried over to the next year as organic N. The amount of fertilizer N applied to crops increased dramatically from 0.928 Tg in 1981 to a peak level of 1.68 Tg in 2000. There were significant changes in manure N production and application to farmland both on a regional and a temporal basis.
Estimating soil water content from surface digital image gray level measurements under visible spectrum
Authors: Zhu Yuanjun , Wang Yunqiang , Shao Mingan , Horton Robert
Published: March 2011

Zhu, Y., Wang, Y., Shao, M. and Horton, R. 2011. Estimating soil water content from surface digital image gray level measurements under visible spectrum. Can. J. Soil Sci. 91: 69–76. Determining soil water content (SWC) is fundamental for soil science, ecology and hydrology. Many methods are put forward to measure SWC, such as drying soil samples, neutron probes, time domain reflectrometry (TDR) and remote sensing. Sampling and drying soil is time-consuming. A neutron probe cannot determine SWC of surface soil accurately because neutrons escape when they are emitted near soil surface and TDR is, to some extent, influenced by soil salinity and temperature. Remote sensing can obtain SWC over a large area across a range of temporal and spatial scales. Complicated terrain and atmospheric conditions often make remote sensing data unreliable. Determining SWC from surface gray level (GL) measurements in the visible spectrum may have advantages over other remote sensing techniques, because surface soil images can be easily acquired by digital cameras, even with complicated landforms and meteorological conditions. However, few studies use this method, and further work is required to develop the ability of visible spectrum digital images to accurately estimate SWC. In this study, 42 soil samples were collected to investigate the relationship between surface GL and SWC using computer processing of soil surface images acquired by a digital camera. After establishing an equation to describe this relationship, a simple calibrated model was developed. The calibrated model was validated by an independent set of 48 soil samples. The results indicate that surface GL was sensitive to SWC. There was a negative linear relationship between surface GL and the square of SWC for the 42 calibration soil samples (correlation coefficients >0.91). Based on this negative relationship, a model was established to estimate SWC from surface GL. The results of model validation showed the estimated SWCs by surface GL were very close to the measured SWCs (correlation coefficient=0.99 at a significant level of 0.01). Generally, SWC could be estimated from surface GL for a given soil, and the model could be used to quickly and accurately determineg SWC from surface GL measurements.
Evaluation of a polymer treatment as enhancer of phosphorus fertilizer efficiency in wheat
Authors: Karamanos R. E. , Puurveen D.
Published: March 2011

Karamanos, R. E. and Puurveen, D. 2011. Evaluation of a polymer treatment as enhancer of phosphorus fertilizer efficiency in wheat. Can. J. Soil Sci. 91: 123–125. The effectiveness of Avail® was assessed in two 3-yr trials that included an unfertilized control and three rates of seed-placed P (6.5, 13 and 19.5 kg P ha−1) applied as monoammonium phosphate (MAP) with or without Avail®, and arranged in a randomized complete block design with six replications. Neither a significant effect of treating MAP with Avail® nor a significant interaction between Avail® treatment and rate of P on the yield of wheat and P uptake was observed.
Wavelet and Multiscale Methods
Authors: Cohen Albert , Dahmen Wolfgang , DeVore Ronald A. , Kunoth Angela
Published: March 2011

Various scientific models demand finer and finer resolutions of relevant features. Paradoxically, increasing computational power serves to even heighten this demand. Namely, the wealth of available data itself becomes a major obstruction. Extracting essential information from complex structures and developing rigorous models to quantify the quality of information leads to tasks that are not tractable by standard numerical techniques. The last decade has seen the emergence of several new computational methodologies to address this situation. Their common features are the nonlinearity of the solution methods as well as the ability of separating solution characteristics living on different length scales. Perhaps the most prominent examples lie in multigrid methods and adaptive grid solvers. These have advanced the frontiers of computability for certain problem classes in numerical analysis. Other highly visible examples are: regression techniques in nonparametric statistical estimation, the design of universal estimators in the context of mathematical learning theory and machine learning; the investigation of greedy algorithms in complexity theory, compression techniques and encoding in signal and image processing; the solution of global operator equations through the compression of fully populated matrices arising from boundary integral equations with the aid of multipole expansions and hierarchical matrices; attacking problems in high spatial dimensions by sparse grid or hyperbolic wavelet concepts.This workshop proposed to deepen the understanding of the underlying mathematical concepts that drive this new evolution of computation and to promote the exchange of ideas emerging in various disciplines. A special emphasis was placed on high dimensional problems since these amplify even further the need for novel theory and computation.
Low-Dimensional Topology and Number Theory
Authors: Gunnells Paul E. , Neumann Walter D. , Sikora Adam S. , Zagier Don B.
Published: March 2011

The workshop on Low-Dimensional Topology and Number Theory brought together researchers in these areas with the intent of exploring the many tantalizing connections between Low-Dimensional Topology and Number Theory. Some of the most actively discussed topics were the appearances of modularity in quantum invariants and mutual relations between hyperbolic volume, K-theory, and asymptotics of quantum invariants.
Osservazioni sui teoremi di inversione globale
Authors: Ambrosetti Antonio
Published: March 2011

Some global inversion theorems with applications to semilinear ellitptic equation are discussed.
Dependence of SOA oxidation on organic aerosol mass concentration and OH exposure: experimental PAM chamber studies
Authors: Kang E. , Toohey D. W. , Brune W. H.
Published: March 2011

Abstract. The oxidation of secondary organic aerosol (SOA) is studied with mass spectra analysis of SOA formed in a Potential Aerosol Mass (PAM) chamber, a small flow-through photo-oxidation chamber with extremely high OH and ozone levels. The OH exposure from a few minutes in the PAM chamber is similar to that from days to weeks in the atmosphere. The mass spectra were measured with a Quadrupole Aerosol Mass Spectrometer (Q-AMS) for SOA formed from oxidation of α-pinene, m-xylene, p-xylene, and a mixture of the three. The organic mass fractions of m/z 44 (CO2+) and m/z 43 (mainly C2H3O+), named f44 and f43 respectively, are used as indicators of the degree of organic aerosol (OA) oxidation that occurs as the OA mass concentration or the OH exposure are varied. The degree of oxidation is sensitive to both. For a fixed OH exposure, the degree of oxidation initially decreases rapidly and then more slowly as the OA mass concentration increases. For fixed initial precursor VOC amounts, the degree of oxidation increases linearly with OH exposure, with f44 increasing and f43 decreasing. In this study, the degree of SOA oxidation spans much of the range observed in the atmosphere. These results, while sensitive to the determination of f44 and f43, provide evidence that some characteristics of atmospheric OA oxidation can be generated in a PAM chamber. For all measurements in this study, the sum of f44 and f43 is 0.25 ± 0.03, so that the slope of a linear regression is approximately −1 on an f44 vs. f43 plot. This constancy of the sum suggests that these ions are complete proxies for organic mass in the OA studied.
Characterization of submicron aerosols at a rural site in Pearl River Delta of China using an Aerodyne High-Resolution Aerosol Mass Spectrometer
Authors: Huang X.-F. , He L.-Y. , Hu M. , Canagaratna M. R. , Kroll J. H. , Ng N. L. , Zhang Y.-H. , Lin Y. , Xue L. , Sun T.-L. , Liu X.-G. , Shao M. , Jayne J. T. , Worsnop D. R.
Published: March 2011

Abstract. The Pearl River Delta (PRD) region in South China is one of the most economically developed regions in China, but it is also noted for its severe air pollution due to industrial/metropolitan emissions. In order to continuously improve the understanding and quantification of air pollution in this region, an intensive campaign was executed in PRD during October–November 2008. Here, we report and analyze Aerodyne High-Resolution Aerosol Mass Spectrometer measurements at Kaiping, a rural site downwind of the highly-polluted central PRD area, to characterize the general features of submicron particulate pollution in the regional air. The mean measured PMsub>1 mass concentration was 33.1±18.1 μg m−3 during the campaign and composed of organic matter (33.8%), sulfate (33.7%), ammonium (14.0%), nitrate (10.7%), black carbon (6.7%), and chloride (1.1%), which is characterized by high fractions of inorganic ions due to huge emissions of SO2 and NOx in PRD. The average size distributions of the species (except BC) were all dominated by an accumulation mode peaking at ~450 nm in vacuum aerodynamic diameter. Calculations based on high-resolution organic mass spectra indicate that C, H, O, and N on average contributed 56.6, 7.0, 35.1, and 1.3% to the total organic mass, respectively, corresponding to an organic matter mass to organic carbon mass ratio (OM/OC) of 1.77±0.08. Based on the high-resolution organic mass spectral dataset observed, Positive Matrix Factorization (PMF) analysis differentiated the organic aerosol into three components, i.e., biomass burning (BBOA) and two oxygenated (LV-OOA and SV-OOA) organic aerosols, which on average accounted for 24.5, 39.6 and 35.8% of the total organic mass, respectively. The BBOA showed strong features of biomass burning emissions and has been mainly attributed to the open field burning of crop residues after the harvest in PRD rural areas. The LV-OOA and SV-OOA were found to correspond to more aged (and thus less-volatile) and fresher (and semi-volatile) secondary organic aerosol (SOA), respectively. Analysis of meteorological influence supported that regional transport from the central PRD area was the major origin of the PM1 observed at the Kaiping site.
α-Pinene Nitrates: synthesis, yields and atmospheric chemistry
Authors: Ma S. X. , Rindelaub J. D. , McAvey K. M. , Gagare P. D. , Nault B. A. , Ramachandran P. V. , Shepson P. B.
Published: March 2011

Abstract. The biogenic volatile organic compound α-pinene is one of the dominant monoterpenes emitted to the Earth's atmosphere at an estimated rate of ~50 Tg yr−1. Its atmospheric oxidation products in the presence of NO can lead to ozone production, as well as production of secondary organic aerosol (SOA). The major oxidation pathway of α-pinene is reaction with OH, which in the presence of NO can form either α-pinene nitrates or convert NO to NO2, which can photolyze to form ozone. In this work, we successfully synthesized four α-pinene hydroxy nitrates through three different routes, and have identified the 4 individual isomers in α-pinene/OH/NO reaction chamber experiments. From the experiments, we determined their individual production yields, estimated the total RONO2 yield, and calculated the relative branching ratios of the nitrate precursor peroxy radicals (RO2). The combined yield of the four α-pinene nitrates was found to be 13.0 (±0.7) % at atmospheric pressure and 296 K, and the total organic nitrate yield was estimated to be 0.19 (+0.10/−0.06). We also determined the OH rate constants for two of the isomers, and have calculated their overall atmospheric lifetimes, which range between 22 and 38 h.
High-resolution simulations of atmospheric CO2 over complex terrain – representing the Ochsenkopf mountain tall tower
Authors: Pillai D. , Gerbig C. , Ahmadov R. , Rödenbeck C. , Kretschmer R. , Koch T. , Thompson R. , Neininger B. , Lavrič J. V.
Published: March 2011

Abstract. Accurate simulation of the spatial and temporal variability of tracer mixing ratios over complex terrain is challenging, but essential in order to utilize measurements made in complex orography (e.g. mountain and coastal sites) in an atmospheric inverse framework to better estimate regional fluxes of these trace gases. This study investigates the ability of high-resolution modeling tools to simulate meteorological and CO2 fields around Ochsenkopf tall tower, situated in Fichtelgebirge mountain range – Germany (1022 m a.s.l.; 50°1'48'' N, 11°48'30'' E). We used tower measurements made at different heights for different seasons together with the measurements from an aircraft campaign. Two tracer transport models – WRF (Eulerian based) and STILT (Lagrangian based), both with a 2 km horizontal resolution – are used together with the satellite-based biospheric model VPRM to simulate the distribution of atmospheric CO2 concentration over Ochsenkopf. The results suggest that the high-resolution models can capture diurnal, seasonal and synoptic variability of observed mixing ratios much better than coarse global models. The effects of mesoscale transports such as mountain-valley circulations and mountain-wave activities on atmospheric CO2 distributions are reproduced remarkably well in the high-resolution models. With this study, we emphasize the potential of using high-resolution models in the context of inverse modeling frameworks to utilize measurements provided from mountain or complex terrain sites.
HULIS in nanoaerosol clusters; investigations of surface tension and aggregate formation using molecular dynamics simulations
Authors: Hede T. , Li X. , Leck C. , Tu Y. , Ågren H.
Published: March 2011

Abstract. Cloud condensation nuclei act as cores for water vapor condensation, and their composition and chemical properties may enhance or depress the ability for droplet growth. In this study we use molecular dynamics simulations to show that humic-like substances of larger systems (8.6 nm in diameter) mimic experimental data well referring to reduction of surface tension. The structural properties examined show the ability for the humic-like substances to aggregate inside the nanoaerosol clusters.