SummaryGlyphosate‐resistant Ambrosia trifida is a competitive and difficult‐to‐control annual broad‐leaved weed in several agronomic crops in the Midwestern United States and Ontario, Canada. The objectives of this study were to compare treatments for control of glyphosate‐resistant A. trifida with tillage followed by pre‐emergence (PRE) and/or post‐emergence (POST) herbicides in glyphosate‐resistant maize and to determine the impact of A. trifida escapes on maize yield. Field experiments were conducted in 2013 and 2014 in grower fields infested with glyphosate‐resistant A. trifida. Tillage prior to maize sowing resulted in 80–85% control compared with no tillage. Tillage followed by PRE application of saflufenacil plus dimethenamid‐P with or without atrazine resulted in 99% control compared with ≤86 and 96% control with PRE herbicides alone at 7 and 21 days after application respectively. Tillage or POST‐only herbicides resulted in 4–14 A. trifida plants m−2, whereas a PRE and POST programme had <3 plants m−2. Maize yield was greatest (13.1–14.2 tonnes ha−1) with tillage followed by PRE and POST herbicide programme. The relationship between maize yield and late‐season density of A. trifida escapes showed a 50% maize yield reduction irrespective of control measures when A. trifida density was 8.4 plants m−2. It was concluded that the combination of tillage with PRE and/or POST herbicides reduced A. trifida density and biomass accumulation early in the season and provided an integrated approach for effective management.

Effective antimicrobial intervention strategies to reduce Shiga toxin–producing Escherichia coli (STEC) risks associated with veal are needed. This study evaluated the efficacy of lactic acid (4.5%, pH 2.0), Citrilow (pH 1.2), and Beefxide (2.25%, pH 2.3) for reducing STEC surrogates on prerigor and chilled bob veal carcasses and monitored the effects of these interventions on chilled carcass color. Dehided bob veal carcasses were inoculated with a five-strain cocktail of rifampin-resistant, surrogate E. coli bacteria. E. coli surrogates were enumerated after inoculation, after water wash, after prechill carcass antimicrobial spray application, after chilling for 24 h, and after postchill carcass antimicrobial spray application; carcass color was measured throughout the process. A standard carcass water wash (~50°C) reduced the STEC surrogate population by 0.9 log CFU/cm2 (P ≤ 0.05). All three antimicrobial sprays applied to prerigor carcasses delivered an additional ~0.5-log reduction (P ≤ 0.05) of the surrogates. Chilling of carcasses for 24 h reduced (P ≤ 0.05) the surrogate population by an additional ~0.4 log cycles. The postchill application of the antimicrobial sprays provided no further reductions. Carcass L*, a*, and b* color values were not different (P > 0.05) among carcass treatments. Generally, the types and concentrations of the antimicrobial sprays evaluated herein did not negatively impact visual or instrumental color of chilled veal carcasses. This study demonstrates that warm water washing, followed by a prechill spray treatment with a low-pH chemical intervention, can effectively reduce STEC risks associated with veal carcasses; this provides processors a validated control point in slaughter operations.

OBJECTIVES:Cartilage fatigue, due to mechanical work, may account for precocious development of degenerative joint disease in the temporomandibular joint (TMJ). This study compared energy densities (mJ/mm³) in TMJs of three diagnostic groups.SETTING AND SAMPLE POPULATION:Sixty-eight subjects (44 women, 24 men) gave informed consent. Diagnostic criteria for temporomandibular disorders (DC/TMD) and imaging were used to group subjects according to presence of jaw muscle or joint pain (+P) and bilateral disk displacement (+DD).MATERIAL AND METHODS:Subjects (+P+DD, n=16; -P+DD, n=16; and -P-DD, n=36) provided cone-beam computed tomography and magnetic resonance images, and jaw-tracking data. Numerical modeling was used to determine TMJ loads (Fnormal). Dynamic stereometry was used to characterize individual-specific data of stress-field dynamics during 10 symmetrical jaw-closing cycles. These data were used to estimate tractional forces (Ftraction). Energy densities were then calculated as W/Q (W=work done or mechanical energy input=tractional force×distance of stress-field translation, Q=volume of cartilage). anova and Tukey-Kramer post hoc analyses tested for intergroup differences.RESULTS:Mean±standard error energy density for the +P+DD group was 12.7±1.5 mJ/mm³ and significantly greater (all adjusted p<0.04) when compared to -P+DD (7.4±1.4 mJ/mm³) and -P-DD (5.8±0.9 mJ/mm³) groups. Energy densities in -P+DD and -P-DD groups were not significantly different.CONCLUSION:Diagnostic group differences in energy densities suggest that mechanical work may be a unique mechanism, which contributes to cartilage fatigue in subjects with pain and disk displacement.

OBJECTIVE:To determine differences in masticatory muscle usage between temporomandibular joint disorders diagnostic groups.SETTING AND SAMPLE POPULATION:Seventy-one informed and consented subjects (27 men; 44 women) participated at the University at Buffalo.MATERIAL AND METHODS:Research diagnostic criteria and imaging data were used to categorize subjects according to the presence/absence +/- of TMJ disc placement (DD) and chronic pain (P) (+DD+P, n=18; +DD-P, n=14; -DD-P, n=39). Electromyographic (EMG)/bite-force calibrations determined subject-specific masseter and temporalis muscle activities per 20 N bite-force (T20N , μV). Over 3 days and nights, subjects collected EMG recordings. Duty factors (DFs, % of recording time) were determined based on threshold intervals (5-9, 10-24, 25-49, 50-79, ≥80% T20N ). anova and Tukey-Kramer post hoc tests identified 1) diagnostic group differences in T20N and 2) the effects of diagnostic group, gender, time and interval on muscle DFs.RESULTS:Mean (±SE) temporalis T20N in +DD+P subjects was significantly higher (71.4±8.8 μV) than masseter T20N in these subjects (19.6±8.8 μV; p=0.001) and in -DD-P subjects (25.3±6.0 μV, p=0.0007). Masseter DFs at 5-9% T20N were significantly higher in +DD-P women (3.48%) than +DD-P men (0.85%) and women and men in both other diagnostic groups (all p<0.03), and in +DD+P women (2.00%) compared to -DD-P men (0.83%; p=0.029). Night-time DFs at 5-9% T20N in +DD-P women (1.97%) were significantly higher than in -DD-P men (0.47%) and women (0.24%; all p<0.01).CONCLUSIONS:Between-group differences were found in masticatory muscle activities in both laboratory and natural environmental settings.

OBJECTIVES:Subjects with/without temporomandibular joint disorders (TMJD) were tested for differences in muscle forces. SETTING AND SAMPLE POPULATION:School of Dental Medicine, University at Buffalo. Ninety-one subjects were classified in four groups based on the presence/absence (±) of chronic myofascial and/or TMJ pain (P) and bilateral disc displacement (DD). MATERIAL AND METHODS:Validated numerical models employed an organizational objective and subjects' anatomy to calculate masticatory muscle forces during static biting. anova and Holm's step-down procedure post hoc tests assessed group differences. Theoretical geometries, representing the range of subjects' muscle orientations, were surveyed via numerical models to identify key combinations resulting in high muscle forces. Effect size (Cohen's d) and anova/post hoc tests assessed group differences in key muscle orientations. RESULTS:+P-DD subjects had significantly higher muscle forces, especially for lateral pterygoid muscles, compared to the other groups (p<0.01) for bite forces that were directed posteromedially or posterolaterally on mandibular molars and posteriorly and slightly medially on mandibular incisors. Key muscle orientations for peak lateral pterygoid muscle forces were identified, and group comparisons showed mean orientation in +P-DD compared to other diagnostic groups was ≥5° more upright for masseter and ≥3° more posteriorly directed for temporalis muscles (all Cohen's d≥0.8). CONCLUSION:Predicted lateral pterygoid muscle forces were significantly higher in +P-DD compared to other groups for specific biting conditions and were attributable, in part, to differences in masseter and temporalis muscle orientations.

BACKGROUND AND OBJECTIVE:Local host-modulation therapy is an emerging approach to prevent disease progression in sites with moderate periodontitis. The combination of simvastatin and alendronate would be an intriguing host-modulatory strategy because of the bone-anabolic properties of simvastatin and the antiresorptive/bone-targeting characteristics of alendronate. The objective of this study was to evaluate the effects of local administration of a simvastatin-alendronate-β-cyclodextrin (SIM-ALN-CD) conjugate for preventing experimental periodontitis bone loss.MATERIAL AND METHODS:Twenty-four mature female Sprague-Dawley rats were treated with three, 12 μL injections, administered one week apart, bilaterally into the palatal/interproximal gingiva. The injections contained: (i) a conjugate of 0.5 mg of SIM and 3.75 mg of ALN-CD in H2 O; (ii) H2 O alone; or (iii) no treatment. One week later, the same sites were subjected to induction of experimental periodontitis by three injections (i.e. one injection administered every other day for five d) of 0.01 mg of Escherichia coli endotoxin [lipopolysaccharide (LPS)] in phosphate-buffered saline (PBS) or PBS alone. After an additional week, the rats were killed, the palates were harvested and interproximal bone volume and adjacent thickness were calculated using microcomputed tomography. Subsequently, specimens were decalcified, and interproximal histologic sections were stained with hematoxylin and eosin for evaluation of alveolar crest osteoclasts and surrounding inflammation. Values were compared among treatment groups using analysis of variance and the Kruskal-Wallis test.RESULTS:Interproximal bone volume was reduced by LPS injections (p ≤ 0.04), yet when experimental periodontitis was preceded by treatment with SIM-ALN-CD, more bone was preserved than after treatment with carrier alone (p = 0.007). While LPS caused a significant loss in bone thickness over the palatal roots (p ≤ 0.04), the injection protocol (PBS) also caused a significant loss of palatal bone thickness (p ≤ 0.03). However, prophylactic SIM-ALN-CD injections resulted in no further loss of bone thickness during experimental periodontitis. LPS injections gave histologic evidence of increased osteoclasts and subsulcular inflammation, both of which were reduced when preceded by treatment with SIM-ALN-CD (p ≤ 0.0002).CONCLUSION:The primary conclusion of this study was that locally applied SIM-ALN-CD has the potential to prevent episodes of periodontitis bone loss.

The effectiveness of a narrow grass hedge in reducing runoff nutrient loads following swine slurry application was examined. Slurry was applied to 0.75 m wide by 4.0 m long plots established on an Aksarben silty clay loam soil located in southeast Nebraska. Manure treatments consisted of no manure application and manure application to meet the 1, 2, or 3 year nitrogen (N) requirements for corn. Runoff water quality was measured during three 30 min simulated rainfall events. The grass hedge did not significantly reduce runoff nutrient transport after the swine slurry, which contained relatively small amounts of manure, was applied. Increasing the N application rate from a 1 year to a 3 year corn N requirement also did not result in a significant increase in N or phosphorus (P) loads in runoff. The grass hedge significantly reduced electrical conductivity (EC) measurements from 0.78 to 0.73 dS m and pH values from 8.16 to 7.85. The rates of transport of dissolved P, particulate P, and total P were each influenced by runoff rate and increased in a linear fashion from 7 to 25, 65 to 357, and 72 to 382 g ha min, respectively. Runoff rate significantly affected rates of transport of NO3-N, NH4-N, and total nitrogen, which increased in a linear fashion from 273 to 1204, 30 to 47, and 323 to 1490 g ha min, respectively. Runoff rate is an important variable that should be considered when estimating nutrient transport following application of swine slurry containing relatively small amounts of nutrients.

Central nervous system organization of masticatory muscles determines the magnitude of joint and muscle forces. Validated computer-assisted models of neuromuscular organization during biting were used to determine organization in individuals with and without temporomandibular disorders (TMD). Ninety-one individuals (47 women, 44 men) were assigned to one of four diagnostic groups based on the presence (+) or absence (-) of pain (P) and bilateral temporomandibular joint disc displacement (DD). Electromyography and bite-forces were measured during right and left incisor and molar biting. Two three-dimensional models employing neuromuscular objectives of minimization of joint loads (MJL) or muscle effort (MME) simulated biting tasks. Evaluations of diagnostic group and gender effects on choice of best-fit model were by analysis of variance (ANOVA) and Tukey-Kramer post hoc tests, evaluations of right-left symmetry were by Chi-square and Fisher's exact statistics, and evaluations of model accuracy were by within-subject linear regressions. MME was the best-fit during left molar biting in +DD individuals and incisor biting in men (all p < 0.03). Incisor biting symmetry in muscle organization was significantly higher (p < 0.03) in healthy individuals compared with those with TMD. Within-subject regressions showed that best-fit model errors were similar among groups: 8 to 15% (0.68 ≤ R(2) ≤ 0.74). These computer-assisted models predicted muscle organization during static biting in humans with and without TMDs.

RATIONALE: Raw agricultural commodities are exempt from food allergen labeling laws. We sought to determine the levels of soybean contamination in various wheat flours and determine any potential risk for soy-allergic consumers. METHODS: A total of 35 wheat flour products were purchased in Lincoln, Nebraska, USA. Products included all-purpose, whole wheat, white wheat, bread, and pastry flours. A representative sample from each package was analyzed for the presence of soybean using a commercial enzyme-linked immunosorbent assay (Soy Allergen Veratox®, Neogen) with a lower limit of quantification of 10 parts per million (ppm, μg/g). Consumption data for wheat flour was extracted from the National Health and Nutrition Examination Survey (NHANES). The population threshold for soy was estimated by screening clinical publications for DBPCFC thresholds and combining data regarding the minimal eliciting dose for objective symptoms for soy-allergic individuals. Quantitative probabilistic risk analysis is demonstrated. RESULTS: Soy was detected in 63% (22/35) of wheat flours tested. Consumption of wheat flour ranged from 2 mg - 900 g at a single eating occasion. Thresholds were found for 54 soy-allergic individuals with the lowest-observed adverse effect levels ranging from 220 mg to >66 g whole soybean equivalents. CONCLUSIONS: Many wheat flours without soy on the label contain detectable levels of soybean. Probabilistic risk assessment shows that the risk of an allergic reaction from soy-contaminated wheat is very low. These results suggest that no changes should be considered to labeling laws regarding soybean commodity contamination in wheat, and we do not advise soy-allergic consumers to avoid wheat-based products.

Analysis of previous data suggested the hypothesis that temporomandibular joint (TMJ) eminence shapes develop ideally to minimize joint loads. Hence, we tested this hypothesis in nine females and eight males in each of two groups, with and without TMJ disc displacement. Participants provided anatomical data used in a joint load minimization numerical model to predict, and jaw-tracking data used to measure, eminence shapes. Coordinate data (x,y) of shapes were fit to third-order polynomials for two sessions, sides, and methods (predicted, measured) for each participant. Inter-session data were reliable and averaged. Those with, compared with those without, disc displacement had higher measured shape range (5:1) and left-right asymmetry prevalence (4:1). In 29 symmetrical individuals, ANCOVA and Bonferroni tests compared vertical dimensions (y) at 11 postero-anterior points (x), 0.5 mm apart. Model-predicted and measured shapes were significantly different (P ≤ 0.01) near the eminence crest, but joint load minimization was consistent with eminence shape for x < 3.0 mm.

Switchgrass (Panicum virgatum L.) is being developed into a perennial, herbaceous, cellulosic feedstock crop for use in temperate regions of the USA. Information on spatial and temporal variation for stands and biomass yield among and within fields in large agroecoregions is not available. Spatial and temporal variation information is needed to model feedstock availability for biorefineries. In this 5-yr study, the spatial and temporal variation for biomass yield and stands was determined among and within 10 fields located in North Dakota, South Dakota, and Nebraska. Switchgrass fields were managed for bioenergy from 2000 to 2004 for the Nebraska locations and 2001 to 2005 for the South Dakota and North Dakota locations. A global positioning system (GPS) receiver was used to repeatedly measure within field quadrat sites for switchgrass stands using frequency grid (2.25 m2) measurements in June for five growing seasons. Sixteen quadrat (≥1 m2) yield samples were taken post-killing frost in the establishment year and in August in subsequent years at each location. Topographic within field effects on switchgrass stand frequency and biomass yields were largely insignificant. Stands tended to increase from establishment year to year 3 and then begin to plateau. Weather factors, which were the principal source of temporal variation, were more important in switchgrass yield variation than on switchgrass stand frequencies. Temporal standard deviations for yield were higher on quadrat sites with higher than average field means while temporal standard deviations were smaller in quadrat sites that had lower than average field means at six locations. In the Northern Great Plains agroecoregion, there is greater temporal and spatial variation for switchgrass biomass yields among fields than within fields. Results indicate that modeling feedstock availability for a biorefinery can be based on field scale yields.

OBJECTIVES:To investigate genetic, biologic, and mechanical factors that affect speed of human tooth movement. Setting and Sample Population - Sixty-six maxillary canines in 33 subjects were translated distally for 84 days.MATERIAL AND METHODS:Distal compressive stresses of 4, 13, 26, 52, or 78 kPa were applied to maxillary canines via segmental mechanics. Dental casts and gingival crevicular fluid (GCF) samples were collected nine to 10 times/subject over 84 days at 1- to 14-day intervals. Three-dimensional tooth movements were measured using a microscope and each subject's series of dental casts. GCF samples were analyzed for total protein, interleukin-1beta (IL-1beta), and interleukin-1 receptor antagonist (IL-1RA). Cheek-wipe samples from 18 subjects were typed for IL-1 gene cluster polymorphisms.RESULTS:Average speeds of distal translation were 0.028 +/- 0.012, 0.043 +/- 0.019, 0.057 +/- 0.024, 0.062 +/- 0.015, and 0.067 +/- 0.024 mm/day for 4, 13, 26, 52, and 78 kPa, respectively. Most teeth moved showed no lag phase (63/66). Three factors significantly affected speed (p = 0.0391) and provided the best predictive model (R(2) = 0.691): Activity index [AI = experimental (IL-1beta/IL-1RA)/control (IL-1beta/IL-1RA)], IL-1RA in GCF, and genotype at IL-1B.CONCLUSIONS:Increased AI and decreased IL-1RA in GCF plus having > or =1 copy of allele 2 at IL-1B(+3954) were associated with faster tooth movement in humans.

Tractional forces on the temporomandibular joint (TMJ) disc predispose tissue fatigue. This study tested the hypotheses that tractional forces: (1) increased with stress-field velocity ( V) and aspect ratio ( AR, contact area diameter/cartilage thickness), and compressive strain (ε); and (2) varied depending on cartilage thickness. Porcine TMJ discs (n = 187) received a 10-N vertical static load via an acrylic indenter for 1, 5, 10, 30, or 60 sec, followed by movement. Physical data were recorded and analyzed by quadratic regression relations and a likelihood ratio test. Results showed non-linear increases in tractional forces that were positively correlated with increased V, AR, and ε when the stress-field moved onto relatively thicker (R2 = 0.83) and thinner cartilage (R2 = 0.86). When V was > 27 mm/sec and AR·ε3, was > 0.09, tractional forces were significantly higher (≤ 12% of peak) when the stress-field moved onto thicker cartilage. Stress-field dynamic mechanics and cartilage thickness significantly affected TMJ disc tractional forces.

Iron chlorosis can limit crop yield, especially on calcareous soil. Typical management for iron chlorosis includes the use of iron fertilizers or chlorosis tolerant cultivars. Calcareous and non-calcareous soil can be interspersed within fields. If chlorosis-prone areas within fields can be predicted accurately, site-specific use of iron fertilizers and chlorosis-tolerant cultivars might be more profitable than uniform management. In this study, the use of vegetation indices (VI) derived from aerial imagery, on-the-go measurement of soil pH and apparent soil electrical conductivity (ECa) were evaluated for their potential to delineate chlorosis management zones. The study was conducted at six sites in 2004 and 2005. There was a significant statistical relationship between grain yield and selected properties at two sites (sites 1 (2005) and 3), moderate relationships at sites 2 and 4, and weak relationships at site 5. For sites 1 (2005) and 3, and generally across all sites, yield was predicted best with the combination of NDVI and deep ECa. These two properties were used to delineate chlorosis management zones for all sites. Sites 1 and 3 showed a good relationship between delineated zones and the selected properties, and would be good candidates for site-specific chlorosis management. For site 5, differences in the properties between mapped zones were small, and the zones had weak relationships to yield. This site would be a poor candidate for site-specific chlorosis management. Based on this study, the delineation of chlorosis management zones from aerial imagery combined with soil ECa appears to be a useful tool for the site-specific management of iron chlorosis.

Knowledge of spatial variability of soil attributes within an agricultural field is critical for successful site-specific crop management. Soil sensing techniques to assess this variability on-the-go are being developed as an alternative to tedious manual soil sampling and laboratory testing. The goal of this study was to evaluate an Agitated Soil Measurement (ASM) method for integrated on-the-go mapping of soil pH, soluble potassium and residual nitrate contents using ion-selective electrodes. To implement ASM, an Integrated Agitation Chamber Module (IACM) was developed and attached to a commercial soil pH mapping implement. Precision of the tested electrodes was assessed through the root mean squared error (RMSE) and ranged from 0.10 for pK to 0.22 for pNO3 (units represent the negative base 10 logarithm of the molar concentration of specified ions). The accuracy of the electrodes was assessed by comparing test results against reference measurements conducted in a commercial soil laboratory using the linear regression method. Average accuracy error ranged from 0.11 for pK to 0.23 for pNO3. In a field simulation test, neither precision nor accuracy errors obtained with ASM were lower than for a previously investigated Direct Soil Measurement (DSM) method, which produced precision errors ranging from 0.11 for pH to 0.22 for pNO3 and accuracy errors ranging from 0.12 for pNO3 to 0.20 for pH. The coefficients of determination (r2) of linear regressions between individual field simulation measurements and corresponding average reference measurements were 0.85–0.89 (pH), 0.50–0.54 (pK), and 0.14–0.32 (pNO3). However, laboratory evaluation of the ASM method revealed substantially lower measurement errors and increased r2 values when compared to the field simulation, indicating that the proposed ASM method retains the potential for improving on-the-go field mapping. Except for reduced electrode abuse and the ability to use less expensive half-cell ion-selective electrodes, physical implementation of ASM through the IACM did not bring substantial improvement over conventionally available DSM. This could be attributed to the design of the IACM and use of half-cell electrodes. Further research is necessary to improve the design of the solution-based measuring equipment and to develop an algorithm integrating on-the-go measurements with other sources of spatial data for an improved decision-making process.

Static mechanical analyses of the masticatory apparatus often assume that jaw muscle activity, as measured using electromyography (EMG), is linearly and constantly related to magnitude of bite force during biting, regardless of bite force-induced tooth-tipping moments. The objective of this study was to test the hypothesis that the relationship between EMG of the jaw muscles and bite force varies with the magnitude and sign of tooth-tipping moments. Seven healthy male subjects produced unilateral static occlusal forces at five biting positions, resulting in sequential changes from buccal (+) to lingual (-) tipping moments on the mandibular first molar. Jaw muscle activities were recorded bilaterally using surface (for temporalis and masseter muscles) and indwelling (for lateral pterygoid muscles) electrodes. Bite forces were recorded and controlled using custom devices. EMG versus bite force data were plotted and regression relationships were calculated for each subject, muscle and biting position. Linear regression analysis, analysis of variance and Bonferroni adjusted least significant difference tests were used to determine the effects of muscle, side (ipsilateral, contralateral) and biting position within subjects. It was found that the relationship between EMG and bite force for different tipping moments differed significantly within a subject and muscle. This was most common in the lateral pterygoid and temporalis muscles (all P=0.042), where slopes of the EMG:bite force relationship varied between 3:1 and >25:1. In the masseter muscle, the EMG:bite force relationship for different tipping moments differed significantly in one subject (P<0.008); slopes varied up to 4.6:1. In conclusion, the relationship between EMG and bite force was linear. However, the slopes of the relationship changed significantly depending on sign (+, -) and magnitude of tipping moments acting on the molars.

BACKGROUND AND OBJECTIVE:Simvastatin, a cholesterol-lowering drug, also stimulates oral bone growth when applied topically, without systemic side-effects. However, the mechanisms involved in vivo are not known. We hypothesized that bone morphogenetic protein-2, nitric oxide synthase, and cyclooxygenase-2 are involved, based on prior in vitro evidence. MATERIAL AND METHODS:A rat bilateral mandible model, where 0.5 mg of simvastatin in methylcellulose gel was placed on one side and gel alone on the other, was used to quantify nitric oxide, cyclooxygenase-2 and bone morphogenetic protein-2 (via tissue extraction, enzyme activity or immunoassay), and to analyze the bone formation rate (via undecalcified histomorphometry). Cyclooxygenase-2 and nitric oxide synthase inhibitors (NS-398 and L-NAME, respectively) were administered intraperitoneally. RESULTS:Simvastatin was found to stimulate local bone morphogenetic protein-2, nitric oxide and the regional bone formation rate (p < 0.05), whereas NS-398 inhibited bone morphogenetic protein-2 and reduced the bone formation rate (p < 0.05). CONCLUSION:These data suggest an association between simvastatin-induced bone morphogenetic protein-2 and bone formation in the mandibular microenvironment, and the negative effect of cyclooxygenase-2 inhibitors on bone growth.

Knowledge of the spatial variation of soil attributes is critical for precision agriculture. On-the-go soil sensors have been able to provide relatively high mapping density while assessing this variation. A new ion-selective electrode (ISE) based approach was developed and tested for simultaneous mapping of soil pH, residual nitrate (NO3-), and soluble potassium (K+) contents. In this article, results of laboratory experiments investigating the effects of key measurement factors on ISE performance are presented. In addition to four different soils, these factors included: soil/water ratio (SWR), quality of water used for electrode rinsing (QWR) and for ion extraction (QWE), presence of ionic strength adjuster (ISA), and solution agitation (stirring). After the targeted ion activity presented by different soils, SWR was the second most influential factor causing increased measurement variance, while the influence of QWE was only significant for pH measurements. Based on this study, the following measurement parameters were recommended: agitated purified water extraction without ISA, addition of a fixed amount of water (preferably 1:1 soil/water ratio), and use of regular (tap) water for electrode rinsing.

Screening germplasm for chemical and nutritional content can be expensive and time consuming. Near infrared spectroscopy (NIRS) and application of geostatistical models can make screening more efficient. The objectives of this study were to utilize these technologies to: (i) generate chemical and nutritional values for the U.S. photoperiod insensitive sorghum collection, (ii) describe variability for those traits, (iii) identify accessions in the highest and lowest 1% for each trait, and (iv) describe relationships among the accessions. Accessions were grown at Ithaca, NE, during 2001 and 2002. Samples of grain were scanned and NIRS equations developed for starch, fat, crude protein, acid detergent fiber, and phosphorus. The NIRS generated values for each accession can be accessed on GRIN at http://www.ars‐grin.gov/cgi‐bin/npgs/html/desclist.pl?69; verified 22 November 2005. The highest and lowest 1% of accessions was identified for each trait by best linear unbiased predictors (BLUPs). Means and standard deviations for observed values and variances due to accessions were calculated. Rank correlations between BLUPs and observed values ranged from r = 0.82 to r = 0.92. Principal component analysis showed that much of the variation is attributable to a contrast of starch with a weighted average of fat, crude protein, acid detergent fiber, and phosphorus. Cluster analyses showed clusters on the basis of canonical values, but no geographical, taxonomical, or morphological interpretation of the clusters was apparent.