bluuebunny/crossref_metadata_2025 huggingface dataset:
THE COPPER STATUS OF SOILS AND FORAGE IN THE VANDERHOOF-FORT FRASER AREA OF BRITISH COLUMBIA
Authors: LOWE L. E. , MILNE I. H.
Published: March 2010

An area in North Central B.C. has been characterized as having unusually low levels of DTPA-extractable soil Cu, and of Cu in grass and legume forage materials, in relation to other agricultural areas in B.C. The results account for the occurrence of Cu deficiency in cattle, and may contribute to difficulties in alfalfa production.
RELEASE OF P IN ORGANIC SOILS UNDER AEROBIC AND ANAEROBIC CONDITIONS
Authors: RACZ G. J.
Published: March 2010

Two organic soil samples were incubated at 10 °C aerobically and anaerobically for varying durations up to 24 mo. After incubation, the inorganic P concentrations were determined by successively extracting the soils with 1 N NH4Cl, 0.5 N neutral NH4, 0.1 N NaOH and 0.5 N H2SO4. All extractable forms of inorganic P increased upon incubation in both samples and for both methods of incubation. Total and all extractable forms of inorganic P for samples incubated anaerobically were usually greater than or about equal to P concentrations in samples incubated aerobically.
ORGANIC MATTER CHARACTERISTICS OF UNDISTURBED AND CULTIVATED CHERNOZEMIC AND SOLONETZIC A HORIZONS
Authors: DORMAAR J. F.
Published: March 2010

Under a wheat-fallow system of farming practised on Brown, Dark Brown, and Black Chernozemic soils, on a Black Solodized Solonetz, and on Brown and Black Solods, organic C decreased by as much as 60%; the humic acid/fulvic acid ratio decreased little for the semiarid soils but up to 38% for the Black soils; ethanol/benzene-extractable organic matter increased by as much as 330%; chelating resin-extractable C increased by 27–115%; and total acidity of the extracted humic substances increased up to 36%. The ash contents of the humic substances from the Ah horizons were all less than 12%, whereas those of the Ap horizons varied between 20 and 28%. Apparent differences between the infrared spectra of the resin-extractable humic substances of the Ah and Ap horizons existed particularly near 2920 and 1550 cm−1 suggesting less aliphatic C-H and amide bonds. Anthropogenic pressures have wrought, therefore, distinct measurable qualitative changes, i.e., the general trend with cultivation was towards humic materials with a decreased proportion of side chain components, such as C-H and NH2 groups, but increased carboxyl group content.
THE PEDOGENETIC ORIGIN AND CHARACTERISTICS OF ORGANIC MATTER OF SOLOD SOILS
Authors: ANDERSON D. W. , JONG E. DE , McDONALD D. S.
Published: March 2010

The pedogenetic origin of dark subsurface horizons of a Dark Brown Solod and Solod-like soil from the prairie region of Saskatchewan was studied. The soils had thick, strongly acidic A horizons, dark-colored B horizons and saline C horizons. Standard soil analyses, humus fractionation and measurement of the plant opal phytolith content of the 20–50 μm fraction were done. The dark B horizons contained 1.5 to 2.0 times more organic carbon than the adjacent horizons. The phytolith content decreased regularly with depth, indicating that the dark horizons were not buried surfaces. Consistent with generally accepted theories, they appeared to have formed by the translocation of humic materials in a high sodium environment. The illuvial humus of the B horizon was predominantly humic acid with a high level of aromaticity. Leachates of sodium-saturated A horizon soil contained organic matter with a ratio of humic:fulvic acids and spectral properties similar to the organic matter of the illuvial B horizons.
RELATIONSHIP BETWEEN SALINITY AND WENNER RESISTIVITY FOR SOME DRYLAND SOILS
Authors: READ D. W. L. , CAMERON D. R.
Published: March 2010

Soil paste electrical conductivity (EC) (mmhos/cm) measurements were correlated with Wenner array conductivities at eight sites. Linear correlation coefficients varied from 0.61 to 0.98. The addition of the independent variables, sand, clay, and water content, improved the relationship on four sites. The largest standard deviation from the regression relationships did not exceed ± 2.9 mmhos/cm (average soil EC near 7.0 mmhos/cm). For most sites soil salinity could be estimated within ± 2.0 mmhos/cm and at certain sites within ± 1.0 mmhos/cm. Although the correlations were not as high as those obtained by others, it was felt the Wenner array technique was still a reasonable approach for assessing and mapping salinity under a wide range of field conditions.
CONTAMINATION OF SHALLOW GROUNDWATER BY AN UNPAVED FEEDLOT
Authors: COOTE D. R. , HORE F. R.
Published: March 2010

An unpaved feedlot on a Guelph loam soil was monitored for its effects on shallow groundwater. Elevated concentrations of nitrate (plus nitrite) nitrogen, chloride, sodium and total carbon were found to follow a distinct contamination plume downslope from the feedlot. Maximum nitrate (plus nitrite) concentrations were observed at a distance of approximately 20 m from the feedlot. Within this distance from the feedlot, organic nitrogen was mineralized and then nitrified. Beyond this zone, nitrogen concentrations declined more rapidly than chloride. Denitrification was likely the cause of this more rapid decline, chloride decline being influenced only by dilution. Contamination of groundwater by nitrate extended to a distance of about 60 m from the feedlot. Phosphorus movement was negligible; it was not detected beyond the lower edge of the feedlot. Contamination by chloride and sodium was evident in migrating groundwater.
EFFECT OF MOISTURE CHANGE AND SALINITY ON THE Mg/Ca RATIO AND RATIO OF Ca/TOTAL CATIONS IN SOIL SOLUTIONS
Authors: CARTER M. R. , WEBSTER G. R. , CAIRNS R. R.
Published: March 2010

The magnitude of change of the Mg/Ca ratio and ratio of Ca/total cations were determined over the available moisture range in the soil solution of saline (Na, Mg and Ca sulfates) and non-saline soils. Estimates of the soil solution were obtained by displacement with ethanol. As the soil moisture declined in saline or near saline soils, the Mg/Ca ratio and Ca/total cation ratio increased and remained relatively stable, respectively. Saturation paste extracts were found to serve as an indicator to changes in the above ratios.
MONOSACCHARIDE COMPOSITION OF SELECTED CANADIAN PEATS
Authors: MORITA H. , MONTGOMERY W. G.
Published: March 2010

The neutral monosaccharides released by the acid hydrolysis of five peat profiles were analyzed by ion exchange chromatography and gas-liquid chromatography in order to ascertain whether monosaccharide composition can be used to differentiate peats. Glucose, mannose and galactose were the predominant monosaccharides found. Changes observed with depth in the relative abundances of the monosaccharides were not always correlated with the degree of decomposition as measured by fibre content or pyrophosphate index. The arabinose to xylose ratio was a diagnostic chemical feature which reflected the degree of decomposition of the peats.
THE AMELIORATING EFFECT OF DOLOMITE ON SOILS THAT HAD RECEIVED HEAVY APPLICATIONS OF POTASSIUM REFINERY DUST
Authors: BALLANTYNE A. K.
Published: March 2010

An increase in wheat yield in 1977 on an Elstow silt loam to levels slightly greater than those of the checks was obtained on dolomite-treated (11.2 and 22.4 t/ha) plots that had formerly received 17.9 and 33.6 t/ha KCl dust, and had subsequent wheat yield reductions of 21 and 53% in 1973, and rapeseed yield reductions of 19 and 25% in 1975. Water-soluble and NH4 Ac-extractable K in the surface horizons were increased by high application of KCl, and the Ca and Mg were reduced; K was not increased below the 55-cm depth. An application of 33.6 t/ha KCl had made this soil, below 45 cm, slightly saline due to Ca and Mg from the upper horizon’s exchange complex, and Cl from the added KCl. Eighteen months after the application of dolomite, K was slightly reduced, Ca mainly restored, and Mg partly restored in the surface 15 cm of this soil. Forty percent of the Cl applied with 33.6 t/ha KCl had leached beyond 213 cm by 1976. An upward movement of Ca and MgCl occurred during 1977.
MINERALOGICAL, PHYSICAL, AND CHEMICAL CHARACTERISTICS OF AMORPHOUS CONSTITUENTS IN SOME PODZOLIC SOILS FROM BRITISH COLUMBIA
Authors: ROSS G. J.
Published: March 2010

The inorganic clay constituents of the B horizons of three Podzolic soils from British Columbia were analyzed by X-ray diffraction, infrared, electron-optical and chemical methods. The amorphous inorganic constituents comprised from 51 to 82% of the clay in these Podzol B horizons. Quartz, feldspar, chlorite, and vermiculite were the dominant minerals in the crystalline portion of the clay. Infrared spectra suggested the presence of appreciable amounts of imogolite in the fine clays of the three soils. Electron optical evidence confirmed its presence in small amounts (< 3%) in the fine clays of the Haney and Marble Hill soils. The majority of the fine clay particles appeared gel-like and did not show the 50 Å spherical "unit particle" characteristic of allophane. The amorphous clay constituents had SiO2/Al2O3 ratios of 0.2–0.4 and consisted therefore mainly of sesquioxides. A portion of the sesquioxides was probably derived from organic-complexed Al and Fe that was precipitated as hydrous oxides during peroxide treatment prior to clay separation. Although the chemical composition and micromorphology of the Podzol B amorphous clay constituents were different from those of allophane, their effect on some soil properties was the same as that of allophane. For example, the soil-surface charge was strongly dependent on pH and the high soil plasticity was lost during drying. This behavior was probably significantly enhanced by the relatively high organic matter contents of the samples studied. There was no evidence, however, for any specificity in cation exchange, such as retention of Rb against exchange with Na.
CEMENT OF DURIC HORIZONS, MICROMORPHOLOGY AND ENERGY DISPERSIVE ANALYSIS
Authors: McKEAGUE J. A. , PROTZ R.
Published: March 2010

Analysis by energy dispersive X-ray spectrometry (EDS) of cutans linking grains in coarse-textured duric horizons with plectic fabrics indicated that Al-organic material was a component of the cement. (Al, Fe)-organic material occurred in voids near the upper surface of duric horizons with porphyroskelic fabrics but EDS was not useful in detecting the cement of such horizons. Ground (2 mm) sandy loam C horizon material from a soil with a dense duric horizon was cemented strongly by as little as 0.1% (Al + Fe) precipitated with Na2 SiO3. Results of this and previous studies suggest that various combinations oa Al, Fe and Si hydrous oxides and humified organic matter act as cementing agents of duric horizons and that very little cement is required to indurate closely packed materials.
OPTIMAL SOIL pH AND SUFFICIENCY CONCENTRATIONS OF N, P AND K FOR MAXIMUM ALFALFA AND ONION YIELDS ON ACID ORGANIC SOILS
Authors: LIEROP W. VAN , MARTEL Y. A. , CESCAS M. P.
Published: March 2010

The optimal soil pH and sufficiency concentrations of N in plants and P, K and Ca + Mg in plants and soils were determined for alfalfa (Medicago sativa L.) and onion (Allium cepa L.) grown on three acid organic soils in a growth chamber experiment. The heaviest (14 t/ha) liming rate reduced soil acidity from pH 3.4 to 5.1 (1 N KCl), pH 3.9–6.2, and pH 2.6–4.9 on soils 1, 2 and 3, respectively. Liming increased alfalfa yields on all soils, but onion yields on only two soils out of three. Yields were, however, not increased by liming soils above pH 4.5 for alfalfa and 4.0 for onion. At maximum yields, the concentration of Ca + Mg in alfalfa at pH 4.5 was about 145 meq/100 g tissue while the concentration in onion at pH 4.0 was about 86 meq, concentrations that are typical for these crops grown successfully on other soils. Alfalfa and onion yields were not increased by fertilizing these soils at higher levels than 200 kg N, 100 kg P and 400 kg K/ha. The average sufficiency concentrations of plant nutrients for obtaining maximum yields were: tissue, 2.0 and 2.1% N, 0.2 and 0.24% P, 1.2 and 1.9% K; soil, 90 and 100 ppm P (13 and 15 μg P/cm3), and 0.8 and 0.9 meq K/100 g (44 and 50 μg K/cm3) for alfalfa and onion, respectively.
RESPONSE OF COMPACT SUBSOILS TO SOIL DISTURBANCE
Authors: WEBSTER D. H.
Published: March 2010

Three years after disturbance of soil, by digging sample pits to a depth of 1 m, soil at a depth of 85–95 cm had greater air porosity and greater total porosity than previously and soil strength of disturbed soil was much less than strength of the undisturbed side wall. At a depth of 25–35 cm, air porosity was increased and soil strength was decreased. Disturbance of wet soil tended to have less beneficial or detrimental effects. These data suggest than Berwick and Kentville sandy loams would be amenable to improvement by deep tillage provided moisture conditions were favorable.
HUMUS FRACTION RATIOS AS A MEANS OF DISCRIMINATING BETWEEN HORIZON TYPES
Authors: LOWE L. E.
Published: March 2010

Humus fraction distribution in a wide range of horizon samples was examined by measuring carbon content in humic acid (Ch), in fulvic acid (Cf) and in the strongly colored polyphenolic component of the fulvic acid fraction (Ca). Fraction distribution was described by the ratios Ch/Cf and Ca/Cf. It was concluded that humus fraction ratios were related to horizon types as used in the Canadian System of Soil Classification, and were effective in discriminating between certain horizon types, particularly between Luvisolic Bt and Podzolic Bf. The results also suggested that humus fraction ratios may be effective in separating distinct sub-populations within Ah horizons and Bf horizons in general, based on qualitative differences in organic matter present. Aspects of the role of humus fractions in soil genesis are discussed.
EFFECTS OF PLACEMENT LOCATION FOR PHOSPHORUS BANDED AWAY FROM THE SEED ON GROWTH AND UPTAKE OF SOIL AND FERTILIZER PHOSPHORUS BY FLAX
Authors: SADLER J. M.
Published: March 2010

Growth chamber studies were conducted on the relative effects of various placements of NH4H232PO4 applied at 20 kg P ha−1 in a single band away from the seed on growth, and on uptake of soil and fertilizer P by flax (Linum usitatissimum L. ’Linott’) grown on two P-deficient Chernozemic soils; one calcareous, the other non-calcareous. Crop response was very sensitive to location of the placed P. Placement of the P away from, and up to 3.0 cm to the side and from 0–4.5 cm below the seed on average increased aboveground dry matter yield and P uptake of flax 8 wk after seeding by 2.3- and 2.1-fold, respectively, compared with the non-P fertilized soils. Maximum yields and P uptake, which were approximately four and three and a half times greater, respectively, than the non-P fertilized values, were achieved by placing the P no more than 1.5 cm to the side and 1.5–3.0 cm below the seed. Flax root development studies indicated that this was due largely to root development during the first few weeks being limited to a small cylinder of soil immediately surrounding the single vertical tap root. Distance of placement of P away from the seed was more critical for the calcareous soil, with crop use of the applied P being noticeably less for this soil (4.8–17.3%) than for the non-calcareous soil (18.3–40.2%).
TOTAL PHENOLIC CONTENT IN THE PYROPHOSPHATE EXTRACTS OF TWO PEAT SOIL PROFILES
Authors: MORITA H.
Published: March 2010

The Folin-Ciocalteau reagent was used to determine the total content of soluble peat phenolic compounds by a colorimetric method. The response of known phenolic compounds to the reagent was measured and it indicated its usefulness for studying peat humus. The results showed that the absorbance at 550 nm of the Na4P2O7 extracts of peat materials from two peat soil profiles was correlated with the total phenolic content but anomalous results were encountered in some horizons. Additionally, the total phenolic content per microgram of dissolved organic matter and the behavior of known phenolic compounds revealed that one peat profile had the most reactive phenolics in the bottom horizon.
CHANGES IN NATURAL 15N ABUNDANCE ASSOCIATED WITH PEDOGENIC PROCESSES IN SOIL. I. CHANGES ASSOCIATED WITH SALINE SEEPS
Authors: KARAMANOS R. E. , RENNIE D. A.
Published: March 2010

The δa15N for the total and nitrate soil N from surface samples taken from recharge and discharge areas associated with a saline seep differ significantly. Suggested reasons for these differences are included. These data suggest that the nitrate moving towards the surface with the soluble salts is depleted in the heavier isotope; the very high δa15N for total and nitrate N of surface samples suggests that denitrification has been a dominant process operating in the saline seep area. Incubation studies carried out on Ap samples taken from the recharge and discharge areas have verified that the δa15N (and perhaps also the nature of the mineralizable organic nitrogen) from a "mature" and "recent" saline profile are different from each other, and distinctly different from that of the recharge area.
CHANGES IN NATURAL 15N ABUNDANCE ASSOCIATED WITH PEDOGENIC PROCESSES IN SOIL. II. CHANGES ON DIFFERENT SLOPE POSITIONS
Authors: KARAMANOS R. E. , RENNIE D. A.
Published: March 2010

Rather marked variations in δa15N values were obtained in a study carried out on samples taken from four soils belonging to the Weyburn soil association. The δa15N of the total N of well-drained depressional profiles dropped sharply with depth and, in contrast, for upper slope positions was relatively constant to a depth of approximately 5 m. This characteristic enrichment in the heavier isotope of total nitrogen of surface horizons may represent long-term immobilization of partially oxidized ammonium N into the organic N fraction; δa15N of the total N more closely represents past soil-forming processes while that of the nitrate N appears to reflect, in addition, recent N cycle stresses.
THE USE OF AN ULTRASONIC PROBE IN SOIL DISPERSION AND IN THE BULK ISOLATION OF ORGANO-MINERAL COMPLEXES
Authors: HINDS A. A. , LOWE L. E.
Published: March 2010

Conditions were investigated for using a Biosonic BP-III ultrasonic probe for reproducible soil dispersion. The importance of probe-tip conditions and an instrument rest period between successive dispersions is emphasized. A procedure for bulk isolation of particle size separates is described, based on ultrasonic dispersion and continuous flow centrifugation. For 500-g soil samples, average recovery of soil solids was 98%. The procedure is relatively rapid and should be useful where high yield of size separates is needed for characterization or mineralization studies on organo-mineral complexes.
LONG-RANGE EFFECTS OF INTENSIVE CULTIVATION AND MONOCULTURE ON THE QUALITY OF SOUTHERN ONTARIO SOILS
Authors: KETCHESON J. W.
Published: March 2010

Ontario holds a significant proportion of the land base for Canada’s food production. Many of the soils are vulnerable to the effects of erosion and intense cropping. Laboratory and field studies indicate that monoculture systems without grass-legume forages lower organic C and N equilibrium levels. Structure and tilth, in terms of total porosity and stable aggregation, are impaired. Marked increases in land areas in monoculture, particularly corn and beans, have occurred in the last 20 yr and could lead to lower yield potentials. However, contrary to this expected trend in soil productivity, Ontario’s census records indicate a yield increase of 1.88 t/ha for nine commonly-grown crops over the 20-yr period. Fertilizer recommendations at the end of the period have decreased to approximately 60% of the amount recommended at the beginning. Deterioration of soil by wind and water erosion is a matter of concern. While average losses are estimated between 0.07 and 1.9 t/ha for different watersheds, individual field situations exceed this and may create serious problems in yield reduction and impaired water quality.
NITROUS OXIDE EVOLUTION RATES FROM FERTILIZED SOIL: EFFECTS OF APPLIED NITROGEN
Authors: McKENNEY D. J. , SHUTTLEWORTH K. F. , FINDLAY W. I.
Published: March 2010

Nitrous oxide emission from agricultural soil has been measured in two relatively long-term studies over two different soil types, Brookston clay and Fox sandy loam, located at Woodslee and Harrow Ontario, respectively. The clay plots treated with various amounts (0–366 kg N∙ha−1) of ammonium nitrate, potassium nitrate, or urea were routinely monitored for periods up to 1 yr. Extreme variability in rates within the range 109–1013 molecules∙cm−2∙s−1 was observed (1 × 109 molecules∙cm−2∙s−1 = 4.02 = 10−4 kg N∙ha−1∙day−1 = 1.68 μg N∙m−2∙h−1). Over sandy loam, rates which were lower and more uniform (108–1011 molecules∙cm−2∙s−1) showed a strong correlation with amount of NH4NO3 applied. About 0.25% of applied fertilizer was released as N2O within 80 days following treatment.
CROP RESPONSE TO SALINE SOIL CONDITIONS IN THE PARKLAND AREA OF SASKATCHEWAN
Authors: FOWLER D. B. , HAMM J. W.
Published: March 2010

The salinity tolerance of six annual crop species, wheat, oats, barley, rye, flax and rapeseed, were determined on saline soils that occur north of the Quill Lakes in the northeastern corner of the agricultural area of Saskatchewan. The relative merits of a salt-tolerant grass-legume mixture were also given consideration. The effects of salt stress on spring-sown cultivars became most apparent following exposure to hot, dry summer weather. In contrast, maximum salt tolerance for both winter wheat and winter rye was a function of winterkill. The winterhardiness of both winter annuals was reduced by saline conditions, but winter rye was more adversely affected than winter wheat. Large decreases in seed yield, plant dry weight and height occurred before the effects of increased soil conductivity were expressed for hectoliter weight, 1000-kernel weight, date of maturity, protein content and oil content. Among the spring and winter annual cultivars considered, Bonanza barley and Garry oats demonstrated the greatest salt tolerance. However, where severely saline conditions occurred, mixtures of salt-tolerant perennial grasses and alfalfa proved to be more productive than either barley or oats. The salinity tolerance of all cultivars was greater for years with more favorable growing conditions. It was apparent that stress factors, such as soil salinity, cold, heat, drought, etc., have a cumulative effect in reducing crop performance. This observation emphasizes the importance of minimizing all stress factors when attempting to crop saline soils. Detailed soil analyses indicated that where salts were a problem, the level of salinity was extremely variable, often changing dramatically over short distances. This extreme variability made it difficult to assess the magnitude of the salinity problem. In this regard, crop performance, especially plant height, provided a good indicator for identifying saline areas for purposes of soil testing.
THE RESPONSE OF A GRASS-LEGUME SWARD TO POULTRY MANURE
Authors: MAYNARD D.G. , BOMKE A.A.
Published: March 2010

Poultry numbers, density and potential environmental quality problems have increased greatly in the Lower Fraser Valley. A field experiment was carried out in 1975 and 1976 to determine the effect of manure from a deep-pit laying house on the growth, yield and chemical composition of orchardgrass-ladino clover forage. The manure had N:P:K, ratios of 5.1:2.5:2.0 and 3.5:1.6:1.4 in 1975 and 1976, indicating that its K content relative to N and P was relatively low for forages. Manure rates were 1.25, 2.5, 5.0, 10, 20 and 40 t/ha. In 1976, these rates were applied as a single application in the early spring or split into three equal increments applied in the early spring and following the first and second cuts. The grass component of the sward responded positively to increased manure rates. However, at rates in excess of 2.5 t/ha, the clover was almost totally eliminated from the stand. The maximum 1975 dry matter yield of 7.00 t/ha occurred with 40 t/ha of manure although the rate of yield increase was greatest at rates of 10 t/ha or less. The maximum forage yield of 16.1 t/ha occurred in 1976 at the 20 t/ha split-application rate of manure. At the 5, 10 and 20 t/ha manure rates the split application produced yields about 1.2 t/ha higher than the single application method. Except for the last cuts in both years, manure significantly increased percent total Kjeldahl nitrogen, especially at rates of 20 t/ha or less. Forage NO3-N concentrations exceeded 0.20%, the level cited as being toxic to ruminants, at rates of 20 and 40 t/ha. Forage P concentrations were not significantly affected by manure addition, probably because the available P level in the soil was high. Forage K concentrations were increased at all cuts by increasing manure rates although K was not a factor in the crop response to manure because initial soil K was high. Manure applied at rates in excess of 20t/ha to supply adequate K for forage production would make inefficient use of the N and P in the manure. Good forage yields without damage to the sward and with little problem with high forage NO3 concentrations were obtained at the 10 t/ha rate; however, for manure disposal, rates as high as 20 t/ha could be used.
RESIDUAL EFFECTS OF HIGH RATES OF LIMESTONE, P, K AND Mg APPLICATIONS: EVIDENCE OF INDUCED Mn AND Zn DEFICIENCY IN OATS
Authors: KOWALENKO C. G. , MAAS E. F. , VANLAERHOVEN C. I.
Published: March 2010

In a field plot study to examine the residual effects of heavy rates of coarse limestone (0, 11, 22 and 44 t/ha) in combination with P (560 kg/ha), K (1120 kg/ha), Mg (560 kg/ha) and PKMg (560 + 1120 + 560 kg/ha) applied five growing seasons previously, dry matter production of oats (grain and straw) decreased with increasing rate of limestone application. The decrease was attributed to lime-induced Mn and Zn deficiency. Both Mn and Zn uptake decreased significantly with increased limestone applications. Plant Mn and Zn concentrations were below critical levels in the heavily limed treatments. Neutral normal ammonium acetate soil extractable Mn was significantly related to oats Mn uptake and yield. This same extractant for Zn was not related to uptake of Zn or yield of oats. After the fifth season of cropping, residual limestone (Ca), P and K effects were evident as increased plant uptake and soil extractable Ca, P and K. Residual Mg was shown only by soil extractable Mg.
A ratio ergodic theorem for multiparameter non-singular actions
Authors: Hochman Michael
Published: March 2010

We prove a ratio ergodic theorem for non-singular free

ℤ^d

and

ℝ^d

actions, along balls in an arbitrary norm. Using a Chacon–Ornstein type lemma the proof is reduced to a statement about the amount of mass of a probability measure that can concentrate on (thickened) boundaries of balls in

ℝ^d

. The proof relies on geometric properties of norms, including the Besicovitch covering lemma and the fact that boundaries of balls have lower dimension than the ambient space. We also show that for general group actions, the Besicovitch covering property not only implies the maximal inequality, but is equivalent to it, implying that further generalization may require new methods.
Sagbi bases of Cox–Nagata rings
Authors: Sturmfels Bernd , Xu Zhiqiang
Published: March 2010

We degenerate Cox–Nagata rings to toric algebras by means of sagbi bases induced by conﬁgurations over the rational function ﬁeld. For del Pezzo surfaces, this degeneration implies the Batyrev–Popov conjecture that these rings are presented by ideals of quadrics. For the blow-up of projective
n
-space at
n
+ 3 points, sagbi bases of Cox–Nagata rings establish a link between the Verlinde formula and phylogenetic algebraic geometry, and we use this to answer questions due to D’Cruz–Iarrobino and Buczyńska–Wiśniewski. Inspired by the zonotopal algebras of Holtz and n s Ron, our study emphasizes explicit computations, and offers a new approach to Hilbert functions of fat points.
Bounding the Betti numbers and computing the Euler–Poincaré characteristic of semi-algebraic sets deﬁned by partly quadratic systems of polynomials
Authors: Basu Saugata , Pasechnik Dmitrii V. , Roy Marie-Françoise
Published: March 2010

Let

\mathrm R

be a real closed ﬁeld,

\mathcal Q \subset \mathbb R[Y_1 , \dots , Y_\ell, X_1 , \dots, X_k]

, with

\mathrm{deg}_Y(Q) \leq 2

,

\mathrm{deg}_X( Q) \leq d

,

Q \in \mathcal Q

,

\#(\mathcal Q) = m

, and

\mathcal P \subset \mathrm R[X_1, \dots , X_k]

with

\mathrm{deg}_X(P) \leq d

,

P\in \mathcal P

,

\#(\mathcal P) = s

, and

S \subset \mathrm R^{\ell+k}

a semi-algebraic set deﬁned by a Boolean formula without negations, with atoms

P = 0

,

P\geq 0

,

P\leq 0

,

P\in \mathcal P \cup \mathcal Q

. We prove that the sum of the Betti numbers of

S

is bounded by

\ell^2 (O(s + l + m)\ell d)^{k+2m}.

This is a common generalization of previous results in (Basu, 1999) and (Barvinok, 1997) on bounding the Betti numbers of closed semi-algebraic sets deﬁned by polynomials of degree

d

and 2, respectively. We also describe an algorithm for computing the Euler–Poincaré characteristic of such sets, e generalizing similar algorithms described in (Basu, 1999; Basu 2006). The complexity of the algorithm is bounded by

(\ell smd)^{O(m(m+k))}

.
Multilayer approximation for a confined fluid in a slit pore
Authors: Zarragoicoechea G. J. , Meyra A. G. , Kuz V. A.
Published: March 2010

A simple Lennard-Jones fluid confined in a slit nanopore with hard walls is studied on the basis of a multilayer structured model. Each layer is homogeneous and parallel to the walls of the pore. The Helmholtz energy of this system is constructed following van der Waals-like approximations, with the advantage that the model geometry permits to obtain analytical expressions for the integrals involved. Being the multilayer system in thermodynamic equilibrium, a system of non-linear equations is obtained for the densities and widths of the layers. A numerical solution of the equations gives the density profile and the longitudinal pressures. The results are compared with Monte Carlo simulations and with experimental data for Nitrogen, showing very good agreement.Received: 23 December 2009, Accepted: 24 February 2010; Edited by: D. A. Stariolo; DOI: 10.4279/PIP.020002
Effects of duration of glucocorticoid therapy on relapse rate in antineutrophil cytoplasmic antibody–associated vasculitis: A meta‐analysis
Authors: Walsh Michael , Merkel Peter A. , Mahr Alfred , Jayne David
Published: March 2010

Objective

Disease relapses are common for patients with antineutrophil cytoplasmic antibody–associated vasculitis (AAV). The role of low‐dose glucocorticoids (GC) in relapse prevention is controversial. We undertook a systematic review and meta‐analysis to determine if GC target doses influence relapses of AAV.

Methods

Medline, EMBase, and Cochrane databases were searched for observational studies and randomized controlled trials of treatment of AAV that included a predefined GC treatment plan. The association of GC target dose with the proportion of relapses in studies was assessed using meta‐regression and multilevel generalized linear modeling.

Results

Thirteen studies (983 patients) were identified for inclusion. There were no studies directly comparing GC regimens. We classified 288 patients as having a nonzero GC target dose by study end and 695 patients as having a zero GC target dose by study end. The pooled proportion of patients with a relapse was 36% (95% confidence interval [95% CI] 25–47%). GC regimen was the most significant variable explaining the variability between the proportions of patients with relapses. The proportion of patients with a relapse was 14% (95% CI 10–19%) in nonzero GC target dose studies and 43% (95% CI 33–52%) in zero GC target dose studies. Differences other than GC regimens exist between studies that complicate the comparability of trials and isolation of the variability in relapses due to GC target alone.

Conclusion

Studies with longer courses of GC in AAV are associated with fewer relapses. These results have implications for study design and outcome assessment in clinical trials of AAV.
Association of physical function and physical activity in women with rheumatoid arthritis
Authors: Piva Sara R. , Almeida Gustavo J. M. , Wasko Mary Chester M.
Published: March 2010

Objective

To explore the associations between measures of physical activity (PA) and measures of physical function (PF) in women with rheumatoid arthritis (RA). We hypothesized that the strength of the associations between PA and PF would be moderate, and that after controlling for social and biomedical characteristics, the associations would decrease.

Methods

Women with RA (n = 47, mean ± SD age 56.5 ± 7.0 years) participated in the cross‐sectional analysis of this study. Social and biomedical characteristics explored included age, ethnicity, disease duration, marital and educational status, height, weight, comorbidity, and disease activity. PF was measured by the self‐reported Health Assessment Questionnaire (HAQ) and by a battery of performance‐based measures that included self‐selected gait speed, the 5 chair rise test, and the single leg stance test. PA was measured by a portable activity monitor worn for 10 days, and was characterized in 2 ways: daily average number of steps and daily energy expenditure during moderate levels of PA.

Results

Correlations between measures of PA and PF were small to moderate (zero‐order correlations = 0.189–0.479). After controlling for social and biomedical characteristics, the correlations became smaller (semi‐partial correlations = 0.095–0.277) and only HAQ score remained significantly associated with PA.

Conclusion

Associations between measures of PA and measures of PF were explained, in part, by social and biomedical characteristics in women with RA. The results indicate that measures of PF and PA may represent different constructs and support the need to measure PA in rehabilitation research in RA.
Reliability of patient self‐evaluation of swollen and tender joints in rheumatoid arthritis: A comparison study with ultrasonography, physician, and nurse assessments
Authors: Cheung Peter P. , Ruyssen‐Witrand Adeline , Gossec Laure , Paternotte Simon , Le Bourlout Catherine , Mazieres Maryse , Dougados Maxime
Published: March 2010

Objective

Swollen and tender joints, important in assessing rheumatoid arthritis (RA) activity, have traditionally been evaluated by health professionals. Whether patients can accurately evaluate joints is uncertain. This study evaluated 1) the reliability of patient‐assessed swollen joint counts (SJCs) and tender joint counts (TJCs) versus those assessed by a physician, nurse, and B‐mode ultrasonography (US) and 2) patient‐derived Disease Activity Score in 28 joints (DAS28) compared with physician‐, nurse‐, and US‐derived DAS28.

Methods

Fifty RA patients self‐assessed 28 joints (shoulders, elbows, wrists, metacarpophalangeal, proximal interphalangeal, and knees) for swelling and tenderness. They were then assessed separately by a physician, a nurse, and an ultrasonographer. Nine patients were tested twice (intraobserver reliability), and reliability was assessed at the patient level (28 joints) by intraclass correlation coefficients (ICCs) and at the joint level by prevalence‐adjusted bias‐adjusted kappa.

Results

TJC reliability was good for patient versus physician (ICC 0.85 [95% confidence interval (95% CI) 0.65, 0.94]) and patient versus nurse (ICC 0.76 [95% CI 0.47, 0.90]). However, SJC reliability was poor for patient versus physician (ICC 0.41 [95% CI −0.05, 0.72]) and patient versus nurse (ICC 0.44 [95% CI −0.005, 0.74]). SJC reliability was poor in all assessors compared with B‐mode US, particularly patient‐assessed SJC (ICC 0.22 [95% CI −0.25, 0.61]). However, patient‐derived DAS28 correlated well with US‐derived DAS28 (ICC 0.95 [95% CI 0.87, 0.98]). Intraobserver reliability was good for all assessors for TJC, but was lower for SJC.

Conclusion

Patient‐derived DAS28 is at least as reliable as physician‐, nurse‐, or US‐derived DAS28, despite poor reliability in patient‐assessed SJC.
Safety and immunogenicity of varicella vaccine in patients with juvenile rheumatic diseases receiving methotrexate and corticosteroids
Authors: Pileggi Gecilmara Salviato , de Souza Cleonice Barbosa Sandoval , Ferriani Virgínia Paes Leme
Published: March 2010

Objective

To evaluate the safety and immunogenicity of varicella vaccine (VV) in susceptible patients with juvenile rheumatic diseases receiving methotrexate and corticosteroids.

Methods

Twenty‐five patients with juvenile rheumatic diseases (ages 2–19 years) and 18 healthy children and adolescents (ages 3–18 years) received a single dose of VV. All 25 patients were receiving methotrexate; 13 were also receiving prednisone and 5 were also receiving other disease‐modifying antirheumatic drugs. None of the vaccinated patients or controls had a previous history of varicella. Anti–varicella‐zoster virus IgG antibody (anti–VZV‐IgG) titers were measured by enzyme‐linked immunosorbent assay immediately before, 4–6 weeks after, and 1 year after vaccination. The patients were monitored prospectively for adverse reactions related to the vaccine, exposure, and occurrence of varicella. Disease activity was assessed 3 months before and 3 months after VV.

Results

Twenty patients and all of the controls had negative preimmunization titers of VZV‐IgG, and 5 patients had equivocal levels. Positive VZV‐IgG titers were detected in 10 (50%) of 20 seronegative patients and 13 (72.2%) of 18 controls 4–6 weeks after VV (P = 0.2). One year after vaccination, 8 of 10 patients maintained positive VZV‐IgG titers. No overt varicella episodes and no severe adverse reactions were observed during the followup period. No worsening of clinical parameters and no flares of juvenile rheumatic diseases or changes in doses of medications used were detected after vaccination. In fact, the number of active joints in patients with juvenile idiopathic arthritis was significantly lower after VV (P = 0.009).

Conclusion

VV appears to be safe in patients with juvenile rheumatic diseases receiving methotrexate, as long as continuous prospective vigilance for side effects is performed.
Electronic medical records for discovery research in rheumatoid arthritis
Authors: Liao Katherine P. , Cai Tianxi , Gainer Vivian , Goryachev Sergey , Zeng‐treitler Qing , Raychaudhuri Soumya , Szolovits Peter , Churchill Susanne , Murphy Shawn , Kohane Isaac , Karlson Elizabeth W. , Plenge Robert M.
Published: March 2010

Objective

Electronic medical records (EMRs) are a rich data source for discovery research but are underutilized due to the difficulty of extracting highly accurate clinical data. We assessed whether a classification algorithm incorporating narrative EMR data (typed physician notes) more accurately classifies subjects with rheumatoid arthritis (RA) compared with an algorithm using codified EMR data alone.

Methods

Subjects with ≥1 International Classification of Diseases, Ninth Revision RA code (714.xx) or who had anti–cyclic citrullinated peptide (anti‐CCP) checked in the EMR of 2 large academic centers were included in an “RA Mart” (n = 29,432). For all 29,432 subjects, we extracted narrative (using natural language processing) and codified RA clinical information. In a training set of 96 RA and 404 non‐RA cases from the RA Mart classified by medical record review, we used narrative and codified data to develop classification algorithms using logistic regression. These algorithms were applied to the entire RA Mart. We calculated and compared the positive predictive value (PPV) of these algorithms by reviewing the records of an additional 400 subjects classified as having RA by the algorithms.

Results

A complete algorithm (narrative and codified data) classified RA subjects with a significantly higher PPV of 94% than an algorithm with codified data alone (PPV of 88%). Characteristics of the RA cohort identified by the complete algorithm were comparable to existing RA cohorts (80% women, 63% anti‐CCP positive, and 59% positive for erosions).

Conclusion

We demonstrate the ability to utilize complete EMR data to define an RA cohort with a PPV of 94%, which was superior to an algorithm using codified data alone.
Changes in vitamin D levels in patients with systemic lupus erythematosus: Effects on fatigue, disease activity, and damage
Authors: Ruiz‐Irastorza Guillermo , Gordo Susana , Olivares Nerea , Egurbide Maria‐Victoria , Aguirre Ciriaco
Published: March 2010

Objective

To analyze whether changes in serum 25‐hydroxyvitamin D (25[OH]D) levels affect activity, irreversible organ damage, and fatigue in systemic lupus erythematosus (SLE).

Methods

We performed an observational study of 80 patients with SLE included in a previous cross‐sectional study of 25(OH)D, reassessed 2 years later. Oral vitamin D3 was recommended in those with low baseline 25(OH)D levels. The relationship between changes in 25(OH)D levels from baseline and changes in fatigue (measured by a 0–10 visual analog scale [VAS]), SLE activity (measured by the Systemic Lupus Erythematosus Disease Activity Index [SLEDAI]), and irreversible organ damage (measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI]) were analyzed.

Results

Sixty patients took vitamin D3. Mean 25(OH)D levels increased among all treated patients (P = 0.044), in those with baseline vitamin D levels <30 ng/ml (P < 0.001), and in those with baseline vitamin D levels <10 ng/ml (P = 0.005). Fifty‐seven patients (71%) still had 25(OH)D levels <30 ng/ml and 5 (6%) had 25(OH)D levels <10 ng/ml. Inverse significant correlations between 25(OH)D levels and the VAS (P = 0.001) and between changes in 25(OH)D levels and changes in the VAS in patients with baseline 25(OH)D levels <30 ng/ml (P = 0.017) were found. No significant correlations were seen between the variation of the SLEDAI or SDI values and the variation in 25(OH)D levels (P = 0.87 and P = 0.63, respectively).

Conclusion

Increasing 25(OH)D levels may have a beneficial effect on fatigue. Our results do not support any effects of increasing 25(OH)D levels on SLE severity, although they are limited by the insufficient 25(OH)D response to the recommended regimen of oral vitamin D3 replacement.
A Preliminary Analysis of the Relationship Between Jaw‐Muscle Architecture and Jaw‐Muscle Electromyography During Chewing Across Primates
Authors: Vinyard Christopher J. , Taylor Andrea B.
Published: March 2010

The architectural arrangement of the fibers within a muscle has a significant impact on how a muscle functions. Recent work on primate jaw‐muscle architecture demonstrates significant associations with dietary variation and feeding behaviors. In this study, the relationship between masseter and temporalis muscle architecture and jaw‐muscle activity patterns is explored using Belanger's treeshrews and 11 primate species, including two genera of strepsirrhines (Lemur and Otolemur) and five genera of anthropoids (Aotus, Callithrix, Cebus, Macaca, and Papio). Jaw‐muscle weights, fiber lengths, and physiologic cross‐sectional areas (PCSA) were quantified for this preliminary analysis or collected from the literature and compared to published electromyographic recordings from these muscles. Results indicate that masseter architecture is unrelated to the superficial masseter working‐side/balancing‐side (W/B) ratio across primate species. Alternatively, relative temporalis architecture is correlated with temporalis W/B ratios across primates. Specifically, relative temporalis PCSA is inversely related to the W/B ratio for the anterior temporalis, indicating that as animals recruit a larger relative percentage of their balancing‐side temporalis, they possess the ability to generate relatively larger amounts of force from these muscles. These findings support three broader conclusions. First, masseter muscle architecture may have experienced divergent evolution across different primate clades related to novel functional roles in different groups. Second, the temporalis may be functionally constrained (relative to the masseter) across primates in its functional role of creating vertical occlusal forces during chewing. Finally, the contrasting results for the masseter and temporalis suggest that the fiber architecture of these muscles has evolved as distinct functional units in primates. Anat Rec, 293:572–582, 2010. © 2010 Wiley‐Liss, Inc.
Mechanical Impact of Incisor Loading on the Primate Midfacial Skeleton and its Relevance to Human Evolution
Authors: Wang Qian , Wright Barth W. , Smith Amanda , Chalk Janine , Byron Craig D.
Published: March 2010

The midfacial skeleton in the human lineage demonstrates a wide spectrum of variation that may be the consequence of different environmental and mechanical selective pressures. However, different facial configurations may develop under comparable selective regimes. For example, the Neanderthal high and projected face and the Inuit broad and flat face are hypothesized to be the consequence of (1) life in a cold climate, and (2) excessive paramasticatory stresses focused on the anterior dentition. In this study, the second of these two hypotheses is tested using finite element analyses of a monkey skull. Results indicate that incisor loading induces heavy stress in the anterior midface of macaques. Additional analyses using incremental increases in the anteroinferior tilt of the skull to simulate different magnitudes of facial projection revealed that comparable muscular force generates less stress in a less‐projected face. However, the findings of our final analyses, which attempted to combine biting with the incisors and pulling with the hands, differed from the analyses that mimicked only incisor loading (without any sort of anterior pulling component). These findings suggest that shortening the face may be the most effective way to compensate for anterior dental loading but not necessarily offset the forces incurred when using the anterior dentition as a vice for various paramasticatory behaviors. Although Neanderthals may have frequently loaded their anterior dentition, countervailing selection pressures, such as the inclusion of tough foods in the diet that demanded molar grinding, may have selected for a longer face with a lower load‐ to lever‐arm ratio. Anat Rec, 293:607–617, 2010. © 2010 Wiley‐Liss, Inc.