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Writing nutrient management plans for Christmas tree production requires accurate values for nutrient removal and harvest records. Freshly cut trees of each of Norway spruce (Picea abies), Canaan fir (Abies balsamea var. phanerolepis), and Douglas fir (Pseudotsuga menziesii) were collected in December 2005. Minimum, maximum, and mean cut tree size measurements were documented. Nutrient contents were calculated and there were no significant differences in nutrient uptake values among species. In a spacing of 1.5 m × 1.5 m (4302 trees per hectare), a clear-cut harvest would remove on average (kg/ha) 560 nitrogen (N), 60.87 phosphorus (P), 168 potassium (K), 243.51 calcium (Ca), 37.75 magnesium (Mg), 28.25 sulfur (S), 0.54 boron (B), 3.39 iron (Fe), 4.74 manganese (Mn), 0.11 copper (Cu), 2.79 zinc (Zn), 2.92 aluminum (Al), 105.85 chlorine (Cl), 0.02 molybdenum (Mo), and 1.44 sodium (Na). Except for Mn and Na, nutrient removal increased linearly as dry weight of whole tree increased. [ABSTRACT FROM AUTHOR]

Relatively little is known about the behavior and toxicity of nanoparticles in the environment. Objectives of work presented here include establishing the toxicity of a variety of silver nanoparticles (AgNPs) to Daphnia magna neonates, assessing the applicability of a commonly used bioassay for testing AgNPs, and determining the advantages and disadvantages of multiple characterization techniques for AgNPs in simple aquatic systems. Daphnia magna were exposed to a silver nitrate solution and AgNPs suspensions including commercially available AgNPs (uncoated and coated), and laboratory-synthesized AgNPs (coated with coffee or citrate). The nanoparticle suspensions were analyzed for silver concentration (microwave acid digestions), size (dynamic light scattering and electron microscopy), shape (electron microscopy), surface charge (zeta potentiometer), and chemical speciation (X-ray absorption spectroscopy, X-ray diffraction). Toxicities of filtered (100 nm) versus unfiltered suspensions were compared. Additionally, effects from addition of food were examined. Stock suspensions were prepared by adding AgNPs to moderately hard reconstituted water, which were then diluted and used straight or after filtration with 100-nm filters. All nanoparticle exposure suspensions, at every time interval, were digested via microwave digester and analyzed by inductively coupled argon plasma-optical emission spectroscopy or graphite furnace-atomic absorption spectroscopy. Dose-response curves were generated and median lethal concentration (LC50) values calculated. The LC50 values for the unfiltered particles were (in µg/L): 1.1 ± 0.1-AgNO; 1.0 ± 0.1-coffee coated; 1.1 ± 0.2-citrate coated; 16.7 ± 2.4 Sigma Aldrich Ag-nanoparticles (SA) uncoated; 31.5 ± 8.1 SA coated. LC50 values for the filtered particles were (in µg/L): 0.7 ± 0.1-AgNO; 1.4 ± 0.1-SA uncoated; 4.4 ± 1.4-SA coated. The LC50 resulting from the addition of food was 176.4 ± 25.5-SA coated. Recommendations presented in this study include AgNP handling methods, effects from sample preparation, and advantages/disadvantages of different nanoparticle characterization techniques. Environ. Toxicol. Chem. 2010;29:2742-2750. © 2010 SETAC [ABSTRACT FROM AUTHOR]

During exercise, patients with intermittent claudication (IC) have decreased limb arterial blood pressure that recovers during rest. A novel method for assessing dynamic recovery of function is measurement of the hemodynamic response after exercise. Cilostazol (Pletal®), a new agent for the treatment of IC, increases walking distance and may decrease ischemic burden. The objective of this study was to assess the effect of cilostazol versus placebo on hemodynamic measurements after exercise-induced ischemia in patients with IC. Two double-blind, placebo-controlled studies with similar inclusion/exclusion criteria and duration (24 weeks) were pooled. Patients walked on a treadmill at 2.0 miles/h (3.2 km/h) on a 12.5% grade until the claudication-limited maximal walking distance (MWD) was reached. Anterior and posterior tibial pressures were measured with Doppler ultrasound at baseline and at 1, 5, and 9 min during recovery. Area under the curve (AUC), a measure of the time course of recovery of systolic pressure after exercise-induced ischemia, and ankle–brachial index (ABI) were calculated and compared using analysis of variance (ANOVA). All three treatment groups (308 patients randomized to cilostazol 100 mg bid, 303 to cilostazol 50 mg bid, and 299 to placebo) had similar baseline characteristics. Mean post-exercise AUC for cilostazol 100 mg and 50 mg bid versus placebo increased by 0.31 (p = 0.001) and 0.26 (p = 0.004), respectively. Mean resting ABI increased by 0.03 (p = 0.0039) and 0.04 (p = 0.0001) in the cilostazol 100 mg and 50 mg bid groups, respectively. In conclusion, following 24 weeks of treatment, cilostazol ncreased the ABI at rest and improved the recovery time of ankle pressures post-exercise. [ABSTRACT FROM AUTHOR]

The root hairs of plants are tubular projections of root epidermal cells and are suitable for investigating the control of cellular morphogenesis. In wild-type Arabidopsis thaliana (L.) Heynh, growing root hairs were found to exhibit cellular expansion limited to the apical end of the cell, a polarized distribution of organelles in the cytoplasm, and vesicles of several types located near the growing tip. The rhd3 mutant produces short and wavy root hairs with an average volume less than one-third of the wild-type hairs, indicating abnormal cell expansion. The mutant hairs display a striking reduction in vacuole size and a corresponding increase in the relative proportion of cytoplasm throughout hair development. Bead-labeling experiments and ultrastructural analyses indicate that the wavy-hair phenotype of the mutant is caused by asymmetric tip growth, possibly due to abnormally distributed vesicles in cortical areas flanking the hair tips. It is suggested that a major effect of the rhd3 mutation is to inhibit vacuole enlargement which normally accompanies root hair cell expansion. [ABSTRACT FROM AUTHOR]

The accuracy of the Pre‐sidedress Soil Nitrate Test (PSNT) for predicting the need for sidedressing and for its ability to provide satisfactory nitrogen (N) rate recommendations for field corn grown on a diversity of soils and production systems was evaluated. Thirty‐five N‐response experiments were conducted over a six year period in New Jersey. Soil nitrate (NO3) concentrations were determined in the surface 30 cm of soil when corn plants were 30 to 45 cm tall. Soil nitrate‐nitrogen (NO3‐N) concentrations reflected differences in N availability due to manure application. The relationship between soil NO3‐N concentration and relative grain yield was examined using Cate‐Nelson analysis to define the PSNT critical level. Soil NO3‐N concentrations >22 mg/kg were associated with relative yields of 92% or higher. The success rate for the PSNT critical level was 81 % for making the correct predication as to whether sidedress N was needed. The PSNT is useful to determine the need for sidedress N, but PSNT values below the critical level provide limited guidance for predicting the optimum sidedress N appli‐ cation rate. [ABSTRACT FROM PUBLISHER]

Sandy coastal plain soils have relatively low reserves of potassium (K) and may not be able to supply adequate K for intensive soybean [Glycine max (L.) Merr.] production. Field experiments were conducted in 1985 on Goldsboro sandy loam (fine‐loamy, siliceous, thermic Aguic Paleudult) and in 1986 and 1987 on Dothan loamy sand (fine‐loamy, siliceous, thermic Plinthic Paleudult) to determine K fertilizer rate and placement effects on soybean growth and seasonal K accumulation. Treatments were 0, 56, 112, 168, and 224 kg/ha broadcast and 56 kg K/ha banded plus 0, 56, 112, and 168 kg/ha broadcast. Seasonal plant tissue K concentrations were generally increased by K fertilizer rate each year. Method of placement did not have consistent effects on plant K concentration and had little effect on total K accumulation. Grain yield responded to applied K only in 1986 when the initial exchangeable K level was 0.24 cmol/L. Both broadcast and broadcast‐plus‐band placement methods resulted in linear yield increases but yield was generally higher with broadcast placement. A plateau yield level was not exhibited with K rate. The 224 kg/ha broadcast treatment achieved the highest grain yield and was associated with an exchangeable K level of 0.37 cmol/L and a soil solution K concentration of 1.08 mmol/L. When soybean is grown with intensive production practices, there is little benefit to band placement of K on sandy soil testing high in K [ABSTRACT FROM PUBLISHER]

A patient with mitochondrial myopathy is described. Examination of his fundus revealed bilateral vitelliform degeneration of the maculae. This lesion is a focal abnormality of the retinal pigment epithelium and may be a manifestation of the underlying mitochondrial disease. [ABSTRACT FROM PUBLISHER]

The article presents a randomized, sham-controlled trial to evaluate ultrasound in treating tibial fractures. Patients were allocated to sham device or low-intensity pulsed ultrasound (LIPUS) after intramedullary nailing. The study shows that daily LIPU after intramedullary nail fixation did not accelerate radiographic healing or improve functional recovery in patients with tibial fractures.

Purpose: Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.Materials and Methods: Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.Results: A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10cm (IQR: 8-12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).Conclusions: The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates. [ABSTRACT FROM AUTHOR]

The practice of leaving clippings on the lawn recycles nutrients andreduces yard-waste but the residue of unsightly clippings deters widespread adoption. An experiment was conducted on a Kentucky bluegrass(Poa pratensis L.) turf to evaluate mowing practice in combination with various fertilizer types and application rates. The main objective was to minimize clipping yield while achieving acceptable turfgrassquality. The return of clippings, as compared to clipping removal, was associated with fewer weeds and a darker green more luxuriant turf. Furthermore, the benefits of clipping return were achieved using half (97.6 k ha-1 yr-1) as much N as is typicallyapplied (195.2 kg ha-1 yr-1 ) for high maintenance turf. Slow-release fertilizers were shown to reduce spring clipping yield and thereby make the practice of clipping return a more acceptable mowing practice. [ABSTRACT FROM AUTHOR]