bluuebunny/crossref_metadata_2025 huggingface dataset:
Secondary Metabolites in Maca as Affected by Hypocotyl Color, Cultivation History, and Site
Authors: Clément Céline , Diaz Diego , Manrique Ivan , Avula Bharathi , Khan Ihklas A. , Ponce Aguirre Dante D. , Kunz Carmen , Mayer Andrea C. , Kreuzer Michael
Published: March 2010

Maca (Lepidium meyenii Walpers) hypocotyls are reported to have a favorable biological activity in man. The presumed bioactive constituents seem to vary among maca hypocotyl color types, but the residual variation is large. This study tested the hypothesis that, apart from color types, environmental factors have a distinct influence on the concentration of characteristic secondary metabolites in maca. In a field experiment at 4100 m altitude (Peru), maca of four hypocotyl color types was evaluated at two sites with different soil types. At each site, experimental areas were either never cultivated or cultivated with maca 2 to 3 yr ago followed by a fallow period. Applying four color replicates per site and area resulted in 64 plots (100 plants plot−1). Especially color type largely influenced concentrations of macaene, macamides, β‐sitosterol, campesterol, and glucosinolates. Site (also clearly affecting growth yield) was weaker in effect on these metabolites but still significantly influenced concentrations of some constituents, while the effect of cultivation history was widely absent. Macaene, macamides, and β‐sitosterol were negatively correlated with glucosinolates. This shows that environmental conditions and color type have to be considered in producing maca with high concentrations of distinct bioactive metabolites.
Yield and Economic Assessments of Fertilizer Nitrogen and Phosphorus for Processing Tomato with Drip Fertigation
Authors: Zhang T. Q. , Tan C. S. , Liu K. , Drury C. F. , Papadopoulos A. P. , Warner J.
Published: March 2010

Agronomic and economic assessments of response of processing tomato (Lycopersicon Esculentum Mill.) to nutrient application with drip fertigation are essential to optimize soil fertility management that maximizes farmers' profitability in a sustainable manner. A field study was conducted to evaluate the yield and economic responses of drip fertigated processing tomatoes to additions of fertilizer nitrogen (N) and phosphorus (P) from 2003 to 2005. The experiment was arranged in a factorial design with four levels of fertilizer N (0, 120, 240, and 360 kg N ha−1) and three levels of fertilizer P (0, 100, and 200 kg P2O5 ha−1). Fertilizer N application affected biomass yield of stems and leaves, total and marketable fruit yields, N use efficiency, and N agronomic efficiency. However, neither P application nor the interaction between fertilizer N and P influenced these variables. Nitrogen use efficiency and N agronomic efficiency decreased with increases in fertilizer N rate, with N use efficiency averaging 443 kg kg−1 and N agronomic efficiency averaging 237 kg kg−1 Both fruit yields and net economic returns responded quadratically to the fertilizer N rate, with a maximum marketable yield of 127 Mg ha−1 averaged across the 3 yr. The fertilizer N rates were 271 kg N ha−1 for the maximum marketable yield and 265 kg N ha−1 for the optimum economic yield. These values are considerably greater than the current recommendation, due to the largely increased yield with drip fertigation. Fertilizer N should be applied at an increased rate for processing tomatoes with drip fertigation to maximize the economic return.
Precipitation Storage Efficiency during Fallow in Wheat‐Fallow Systems
Authors: Nielsen David C. , Vigil Merle F.
Published: March 2010

Precipitation storage efficiency (PSE) is the fraction of precipitation received in a given time period that is stored in the soil. Average fallow PSE for Great Plains wheat (Triticum aestivum L.)‐fallow (W‐F) production systems have ranged widely (10–53%). Study objectives were to compare PSE in conventionally tilled (CT) and no‐till (NT) W‐F systems over 10 seasons at Akron, CO, against published values and to identify meteorological conditions that may influence PSE. Soil water measurements were made four times during each fallow period, dividing the fallow season into three periods (first summer, fall–winter–spring, second summer). Precipitation was measured in the plot area and other meteorological conditions were measured at a nearby weather station. The 14‐mo fallow PSE averaged 20% (range 8–34%) for CT and 35% (range 20–51%) for NT, much lower than previously reported for NT at Akron. During the second summer period, PSE was not different between the two systems. The largest PSE difference between the two systems was seen during the fall–winter–spring period (32 vs. 81%). Fallow soil water increased an average of 111 mm under CT and 188 mm under NT. The PSE during the three fallow periods was related to tillage, precipitation, air temperature, vapor pressure deficit, and wind speed, but sometimes counter‐intuitively. A simple linear regression using inputs of tillage system, percentage of fallow precipitation events with amounts between 5 and 15 mm, and percentage of fallow precipitation events with amounts > 25 mm can be used to estimate PSE and fallow period water storage.
Fertilizer Effectiveness of Phosphorus Recovered from Broiler Litter
Authors: Szogi Ariel A. , Bauer Philip J. , Vanotti Matias B.
Published: March 2010

Phosphorus can be recovered from broiler litter using a new process (“quick wash”). However, limited information is available on the beneficial use of this P product as plant fertilizer. The objective of this study was to determine the agronomic effectiveness of this P material. A greenhouse study was conducted with annual ryegrass (Lolium multiflorum Lam.) to compare the recovered phosphorus (RP) to both commercial triple superphosphate (TSP) and raw broiler litter (BL) as a P source. The study consisted of a 7‐wk experiment that was repeated three times. Fertilizer rates were 0, 22, 44, 88, and 176 mg P kg−1 soil. Three harvests of the ryegrass were made at 2‐wk intervals. On average, biomass production was higher than the control with no P for plants fertilized with RP, BL, or TSP. Total P uptake increased linearly with application rate for all three fertilizer materials. At the highest application rate, total P uptake was 36.1 mg pot−1 for TSP, 21.3 mg pot−1 for the BL, and 17.3 mg pot−1 for the RP. Chemical analysis of the RP material revealed that more than 90% of the total P in the RP material was mostly as citrate‐soluble. Mehlich‐3 extractable soil P at the end of the experiment indicated that less RP material dissolved than TSP during this short study. The RP material appears to have potential as a fertilizer.
Yield and Environmental Effects of Summer Pig Slurry Applications to Irrigated Alfalfa under Mediterranean Conditions
Authors: Salmerón Montserrat , Cavero José , Delgado Ignacio , Isla Ramón
Published: March 2010

In the Ebro Valley (Spain), the intensive pig (Sus scrofa) production combined with a limited nearby cereal growing area for spreading pig slurry residue is leading more farmers to apply slurry to alfalfa (Medicago sativa L.). The effects of summer pig slurry applications on irrigated alfalfa yield and the environment have not been adequately established. An experiment was conducted in 12 drainage lysimeters in 2007 and 2008, where two rates of pig slurry (low (LD), 140 kg N ha−1 yr−1; high (HD) 340 kg N ha−1 yr−1) were compared to a P‐K fertilized control. Application of pig slurry did not affect accumulated forage yield after 2 yr (37.3 Mg ha−1). Forage N concentration and total N extractions (1214 kg ha−1) were similar for all treatments, revealing a high flexibility of the crop to adjust symbiotic N fixation depending on mineral N availability. The NO3−–N and P concentrations and loads in drainage were very low (< 2 kg N ha−1 yr−1 and 0.035 kg P ha−1 yr−1) and not affected by the pig slurry applications. Soil P in the surface layer (0–0.3 m) increased by a 19% as a result of both pig slurry and P fertilization. Application of pig slurry did not significantly increase the Zn and Cu content of the soil. These results indicate the feasibility of moderate pig slurry applications to growing alfalfa in the Ebro Valley, which will improve the management of this residue.
Nutritive Value and Herbage Accumulation Rates of Pastures Sown to Grass, Legume, and Chicory Mixtures
Authors: Sanderson Matt
Published: March 2010

Planting forage mixtures may benefit pasture herbage production; however, changes in botanical composition could cause variable (unstable) nutritive value. A grazing study was conducted to compare forage mixtures for variation in herbage nutritive value with time and herbage accumulation rate. In August 2001, four mixtures (two, three, six, and nine species of grasses, legumes and chicory, Cichorium intybus L) were established in replicated 1‐ha pastures (eight total) in central Pennsylvania. Pastures were grazed by dairy cattle (Bos taurus) from April to September of 2002 and 2003 and sampled frequently for nutritive value and herbage accumulation rate in April, July, and September each year. The intra‐annual variation (across all sampling periods within years) in fiber and digestibility was similar among mixtures; however, variation in crude protein (CP) was greater for the six‐species mixture than others in 2003. Concentration of CP (range of 155–250 g kg−1 dry matter) seemed to be controlled by herbage legume proportion (Pearson r of 0.33–0.90), whereas fiber (range of 278–506 g kg−1) and digestibility (range of 740–895 g kg−1) were controlled by the grass proportion (Pearson r of 0.54–0.88). The three‐, six‐, and nine‐species mixtures (all with chicory) had greater herbage accumulation rates than the orchardgrass (Dactylis glomerata L.)‐white clover (Trifolium repens L.) mixture in 2002, a dry year. Accumulation rates were similar among mixtures (avg of 62 kg ha−1d−1 in spring and 47 kg ha−1d−1 in summer) in 2003 with more rainfall. Complex forage mixtures were not inherently unstable in herbage nutritive value.
Meadow Fescue, Tall Fescue, and Orchardgrass Response to Defoliation Management
Authors: Brink G. E. , Casler M. D. , Martin N. P.
Published: March 2010

Meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.] represents an alternative to temperate grasses typically used in forage‐livestock systems. Our objective was to compare the productivity, nutritive value, and persistence of diverse meadow fescue cultivars with that of tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] and orchardgrass (Dactylis glomerata L.) when harvested by regimes representing lax and severe hay production and rotational grazing. ‘Azov’ (plant introduction strain cross), ‘Bartura’ (commercial cultivar), and ‘Hidden Valley’ (naturalized population) meadow fescue, ‘Barolex’ tall fescue, and ‘Bronc’ orchardgrass were harvested infrequently (40‐ to 65‐d harvest interval) or frequently (when plants reached 25‐cm sward height) to a 5‐ or 10‐cm residual sward height (RSH) at two Wisconsin locations in 2 yr. Annual dry matter (DM) yield of all grasses was greater when harvested infrequently (7.46 Mg ha−1) than frequently (5.92 Mg ha−1), or at 5 cm (7.52 Mg ha−1) than 10‐cm RSH (5.88 Mg ha−1). Tall fescue and orchardgrass annual yield was greater than that of all meadow fescues when harvested infrequently, but differences among grasses were relatively small when harvested frequently, particularly at 10‐cm RSH. Neutral detergent fiber digestibility (NDFD) of meadow fescue was 30 to 80 g kg−1 neutral detergent fiber (NDF) greater than that of tall fescue or orchardgrass at every harvest in all environments. Meadow fescue cultivars were less persistent than tall fescue after 2 yr, but were usually equal to or more persistent than orchardgrass. Meadow fescue should be considered as a viable alternative to tall fescue and orchardgrass in temperate, managed intensive rotational grazing systems due to its comparable yield and superior digestibility.
Forage Yield and Nutritive Value of Hard Red and Hard White Winter Wheat
Authors: Holman Johnathon D. , Thompson Curtis R. , Hale Ronald L. , Schlegel Alan J.
Published: March 2010

Six hard red (‘2137’, ‘Jagalene’, ‘Jagger’, ‘OK101’, ‘Stanton’, and ‘Thunderbolt’) and six hard white (‘Burchett’, ‘Lakin’, ‘NuFrontier’, ‘NuHills’, ‘NuHorizon’, and ‘Trego’) winter wheat (Triticum aestivum L.) cultivars were evaluated for forage yield and nutritive value. Forage samples were collected in December, March, and May. Red cultivars averaged greater total season forage yield in one growing season, but yield differences among cultivars within a color group were greater than differences between color groups, indicating that color did not affect yield as much as cultivar. Total growing season forage yield was greatest among red cultivars 2137, Jagalene, Stanton, and Thunderbolt and white cultivar Trego. Color had no effect on forage nutritive value. Crude protein averaged 230 g kg−1 in December, 240 g kg−1 in March, and 140 g kg−1 in May. Acid detergent fiber averaged 190 g kg−1 in December, 240 g kg−1 in March, and 320 g kg−1 in May. Neutral detergent fiber averaged 430 g kg−1 in December, 410 g kg−1 in March, and 550 g kg−1 in May. Total digestible nutrients averaged 790 g kg−1 in December, 740 g kg−1 in March, and 670 g kg−1 in May. Nitrate‐nitrogen averaged 247 mg kg−1 in December, 550 mg kg−1 in March, and 1366 mg kg−1 in May. Both red and white wheat cultivars can be used in a dual‐purpose system with no adverse affects on forage yield or nutritive value. Producers should select cultivars adapted to their grazing system and environment.
Timing and Rate of Nitrogen Application Influence Profitability of Maize Planted at Low and High Densities in Northwest Pakistan
Authors: Amanullah  , Almas Lal K. , Shah Paigham
Published: March 2010

Getting maximum benefits from maize (Zea mays L.) lies not in reducing N rate and its number of splits but in lowering cost per unit production through higher yields. Field experiments were conducted on maize at the New Developmental Research Farm of North West Frontier Province (NWFP) Agricultural University Peshawar during summer 2002 (Y1) and 2003 (Y2) to investigate the effects of variable rates of N and its time of application on the net returns (NR) of maize (cultivar Azam) planted at low and high densities. The 2 × 3 × 6 factorial experiment was designed having two plant densities (D1 = 60,000 and D2 = 100,000 plants ha−1) and three N levels (N1 = 60, N2 = 120 and N3 = 180 kg N ha−1) as main plots, and six split N applications: two equal (S1), three unequal (S2), three equal (S3), four equal (S4), five equal (S5) and five unequal splits (S6) applied at sowing and with first, second, third, and fourth irrigation at 2 wk intervals as subplots. Maize planted at high density gave about 18% higher NR than at low density, and the increase in NR was comparatively more (3%) in the second growing season than the first growing season. Net returns showed positive relationship with increase in N rates, and increased by 19,565 and 31,948 PKR ha−1 with 120 and 180 kg N ha−1, respectively as compared with 60 kg N ha−1 The increase in NR with N3 was 39% greater than N2. Among the N timings, S5 showed the highest NR (16,646 PKR ha−1) and was 3, 21, and 97% greater than S6, S4, and S3,, respectively. The NR from S2 was negative (−783 PKR) when compared with S1 (control). In conclusion, the findings suggests that growing maize at high density applied with 180 kg N ha−1 in five equal or unequal splits could be more economical in terms of NR in the study area.
Nitrogen Use Efficiency and Nitrogen Fertilizer Recovery of Durum Wheat Genotypes as Affected by Interspecific Competition
Authors: Giambalvo Dario , Ruisi Paolo , Di Miceli Giuseppe , Frenda Alfonso Salvatore , Amato Gaetano
Published: March 2010

A better understanding of the genotype response to N fertilization under weed competition is necessary to identify varieties that exhibit high N use efficiency even when weeds compete for available N. Such varieties may be more suitable for low input or organic systems. This study assessed the variations in nitrogen use efficiency (NUE) (and its components) and the recovery of 15N‐labeled fertilizer in three durum wheat (Triticum durum Desf.) genotypes (one landrace and two varieties that differ in terms of plant growth, grain yield potential, and adaptability to stressful environments) grown in the presence or absence of interspecific competition and varying soil N availability (0 or 80 kg N ha−1 fertilization). The results showed that wheat genotypes had different grain yield potentials and the yields were similar when plants were grown in conditions of low N availability and in presence of interspecific competition. Differences among genotypes in N uptake efficiency were very small, and the low NUE value observed for the landrace seemed to be due to its reduced ability to use absorbed N for increasing grain yield compared with the two varieties. Furthermore, the genotypes showed different competitive abilities against competitor, and seemed to depend on the genotypes' ability to reduce resource availability (N) for their competitors rather than on their ability to tolerate a reduction in contested resources due to competitors.
Tillage, Seeding, and Nitrogen Rate Effects on Rice Density, Yield, and Yield Components of Two Rice Cultivars
Authors: Harrell Dustin L. , Blanche Sterling B.
Published: March 2010

Research was conducted for 2 yr on a Crowley silt loam soil (fine, smectitic, thermic Typic Albaqualfs) near Crowley, LA to evaluate the main effects of tillage, seeding and N rate and potential interactions on rice (Oryza sativa L.) density, yield, and yield components. Two tillage systems (conventional and fall‐stale seedbed), four seeding rates (162, 323, 484, and 646 seed m−2) and four N rates (101, 134, 168, and 202 kg ha−1) were evaluated. ‘Jupiter’ and ‘Cheniere’ a medium and long grain cultivar, respectively, were evaluated in separate experiments. Conventional tillage reduced rice plant density as compared with fall‐stale seedbed tillage due to crusting following flush irrigation during seedling emergence. A tillage by N rate interaction was not observed, suggesting optimal N rates are similar for rice grown using a conventional or fall‐stale seedbed. Rough rice grain yield was optimized at 202 and 168 kg N ha−1 for Jupiter and Cheniere, respectively. Grain yields were optimized for Jupiter at 323 seed m−2, while Cheniere required a seeding rate of more than 323 seed m−2 Panicle density was found to be the single most influential yield component on rice yield and was able to explain 49 and 51% of the variation in yield for Jupiter and Cheniere, respectively. Filled grain panicle−1 was inversely related to panicle density highlighting the ability of rice to tiller as a yield compensatory measure when less than optimum rice densities exist. However, total yield compensation may not be feasible at low seeding rates.
Influence of Seeding Rate and Herbicide Treatments on Weed Control, Yield, and Quality of Spring‐Seeded Glyphosate‐Resistant Alfalfa
Authors: Bradley Kevin , Kallenbach Robert , Roberts Craig A.
Published: March 2010

Field trials were conducted in 2005 and 2006 in central and southwest Missouri to investigate the effect of seeding rate and herbicide programs on weed control, forage quality, and yield within the year of establishment in spring seeded glyphosate‐resistant (GR) alfalfa (Medicago sativa L.). In all experiments, EPTC (4.4 kg ha−1), 2,4‐DB plus sethoxydim (1.1 plus 0.21 kg ha−1), imazamox (0.043 kg ha−1) and glyphosate (0.86 kg ae ha−1) were applied to GR alfalfa that was seeded at 4.5, 8.9, 13.5, and 18 kg ha−1 Across all locations, the glyphosate application provided good control of weeds regardless of alfalfa seeding rate. When applied at the same timing, imazamox provided similar levels of annual broadleaf weed control as glyphosate, while 2, 4‐DB plus sethoxydim provided similar levels of annual grass and broadleaf weed control as glyphosate. Neither glyphosate nor the conventional herbicide treatments reduced alfalfa stem density between the first and last annual harvests, but 2, 4‐DB plus sethoxydim resulted in the most visual injury to seedling alfalfa stands and lowered initial yields at all locations. In addition, alfalfa annual yields were similar or higher in the glyphosate treatment compared to the other herbicide programs. Harvested forage in the herbicide treatments generally had greater crude protein (CP) content than the untreated control forage. Application of glyphosate resulted in similar or higher forage CP content compared to conventional herbicide treatments. In vitro true digestibility of the harvested GR alfalfa ranged from 750 to 860 g kg−1 DM at all locations with few differences across herbicide treatments.
Minimizing Immature Fiber and Neps in Upland Cotton
Authors: Bange Michael P. , Long Robert L. , Constable Greg A. , Gordon Stuart G.
Published: March 2010

Immature cotton (Gossypium hirsutum L.) fibers and neps in ginned cotton will affect textile quality and thus can affect overall industry reputations. This study conducted three field studies that systematically varied the timing of harvest aid application to generate differences in the amount of immature fiber and levels of neps in crops at harvest. The aim was to ascertain what crop conditions (percent open bolls, number of immature bolls, percent immature bolls, and percent immature lint mass) at the time of application contribute to these differences, and assess whether these outcomes are influenced by 0, 1, 2 lint cleaning passes. Earlier harvest aid treatments increased neps and the level of neps was best related to fiber linear density (r2 = 0.78). All measurements of crop condition at harvest aid application explained changes in yield and fiber properties well, although the percent immature bolls (r2 > 0.67) can be applied when crops are nonuniform in their maturity, and when they contain fruiting gaps. Relationships between lint cleaning passes and crop condition at harvest aid application showed an interaction between earlier harvest treatments and lint cleaning passes. One lint cleaning pass contributed between 95 and 141 count g−1 more neps, while a second pass added between 101 and 181 count g−1 more neps. This information will be valuable in refining strategies that aim to optimize both yield and fiber quality (including less neps). This study also supported the current recommendation of applying harvest aids at 60% open bolls.
An Efficient Distributed Genetic Algorithm Architecture for Vector Quantizer Design
Authors: Hwang Wen-Jyi , Ou Chien-Min , Hung Peng-Chieh , Yang Cheng-Yen , Yu Tun-Hao
Published: March 2010

This paper presents a novel distributed genetic algorithm (GA) architecture for the design of vector quantizers. The design is based on a multi-core architecture, where each island of the GA is associated with a hardware accelerator and a softcore processor for independent genetic evolutions. An on-chip RAM with a mutex circuit is adopted for the migration of genetic strings among different islands. This allows a simple and flexible migration for the implementation of hardware distributed GA. Experimental results shows that the proposed architecture has significantly lower computational time as compared with its software counterparts running on multicore processors with multithreading for GA-based optimization.
Transdermal Drug Delivery Aided by an Ultrasound Contrast Agent: An In Vitro Experimental Study
Authors: Park Donghee , Yoon Jinhee , Park Jingam , Jung Byungjo , Park Hyunjin , Seo Jongbum
Published: March 2010

Sonophoresis temporarily increases skin permeability such that medicine can be delivered transdermally. Cavitation is believed to be the predominant mechanism in sonophoresis. In this study, an ultrasound contrast agent (UCA) strategy was adopted instead of low frequency ultrasound to assure that cavitation occurred, and the efficacy of sonophoresis with UCA was quantitatively analyzed by optical measurements. The target drug used in this study was 0.1 % Definity® in 70% glycerol, which was delivered into porcine skin samples. Glycerol was used because it is an optical clearing agent, and the efficiency of glycerol delivery could be analyzed with optical measurements. The applied acoustic pressure was approximately 600 kPa at 1 MHz ultrasound with a 10% duty cycle for 60 minutes. Experimental results indicated that the measured relative contrast (RC) after sonophoresis with UCA was approximately 80% higher than RC after sonophoresis without UCA. In addition, the variance of RC was also reduced by more than 50% with the addition of a UCA. The use of a UCA appeared to increase cavitation, demonstrating that the use of a UCA can be effective in transdermal drug delivery (TDD).
An Electrode Array for Limiting Blood Loss During Liver Resection: Optimization via Mathematical Modeling
Authors: Strigel R.M , Schutt D.J , Webster J.G. , Mahvi D.M , Haemmerich D
Published: March 2010

Liver resection is the current standard treatment for patients with both primary and metastatic liver cancer. The principal causes of morbidity and mortality after liver resection are related to blood loss (typically between 0.5 and 1 L), especially in cases where transfusion is required. Blood transfusions have been correlated with decreased long-term survival, increased risk of perioperative mortality and complications. The goal of this study was to evaluate different designs of a radiofrequency (RF) electrode array for use during liver resection. The purpose of this electrode array is to coagulate a slice of tissue including large vessels before resecting along that plane, thereby significantly reducing blood loss. Finite Element Method models were created to evaluate monopolar and bipolar power application, needle and blade shaped electrodes, as well as different electrode distances. Electric current density, temperature distribution, and coagulation zone sizes were measured. The best performance was achieved with a design of blade shaped electrodes (5 × 0.1 mm cross section) spaced 1.5 cm apart. The electrodes have power applied in bipolar mode to two adjacent electrodes, then switched sequentially in short intervals between electrode pairs to rapidly heat the tissue slice. This device produces a ~1.5 cm wide coagulation zone, with temperatures over 97 ºC throughout the tissue slice within 3 min, and may facilitate coagulation of large vessels.
Mathematical Modeling of Epicardial RF Ablation of Atrial Tissue with Overlying Epicardial Fat
Authors: Suárez Ana González , Hornero Fernando , Berjano Enrique J.
Published: March 2010

The efficacy of treating atrial fibrillation by RF ablation on the epicardial surface is currently under question due to the presence of epicardial adipose tissue interposed between the ablation electrode and target site (atrial wall). The problem is probably caused by the electrical conductivity of the fat (0.02 S/m) being lower than that of the atrial tissue (0.4-0.6 S/m). Since our objective is to improve epicardial RF ablation techniques, we planned a study based on a two-dimensional mathematical model including an active electrode, a fragment of epicardial fat over a fragment of atrial tissue, and a section of atrium with circulating blood. Different procedures for applying RF power were studied, such as varying the frequency, using a cooled instead of a dry electrode, and different modes of controlling RF power (constant current, temperature and voltage) for different values of epicardial fat thickness. In general, the results showed that the epicardial fat layer seriously impedes the passage of RF current, thus reducing the effectiveness of atrial wall RF ablation.
Changes in the Expression of Myosins During Postnatal Development of Masseter Muscle in the Microphthalmic Mouse
Authors: Katayama R. , Yamane A. , Fukui T.
Published: March 2010

In the present study, to elucidate the influences of the deficiency of teeth on the masseter muscle, we analyzed changes in the expression of MyHC isoform mRNAs during postnatal development inmi/mimice using real-time PCR. By 8 weeks of age, MyHC I had nearly disappeared in the +/+ mice, while it was still present in themi/mi, and the level of MyHC I mRNA in themi/miwas 5.1-fold higher than that in the+/+(p<0.01). The levels of MyHC IIx mRNAs in themi/mimice were 41 ~ 55% lower than those in the+/+at both 3 weeks and 4 weeks of age (p<0.05). No significant difference in the expression of MyHC IIa and IIb mRNAs in the masseter muscle was found between themi/miand+/+. From these results, we speculate that the deficiency of teeth affects the masseter muscles during the postnatal development.
The Effect of Age on the Gingival Crevicular Fluid Composition During Experimental Gingivitis. A Pilot Study
Authors: Tsalikis Lazaros
Published: March 2010

Background:

Cytokines have been proposed as potentially useful diagnostic or prognostic markers of periodontal inflammation related alterations during the experimental gingivitis model. The role of ageing in periodontal disease needs further elucidation; therefore investigations of its influence on host response are needed.

Objective:

To study the effect of age on interleukins IL -6, IL-8 and TNF-a levels in gingival crevicular fluid (GCF) and their correlations to clinical parameters during experimental gingivitis.

Materials and Methods: Five young subjects (20-22 years old) and five old subjects (61-65 years old), all periodontal healthy, participated in this clinical trial. A professional plaque control programme was undertaken to establish healthy gingival conditions at baseline. Plaque index (PI), gingival index (GI) were recorded at 60 sites at baseline, after 21 days of no oral hygiene and one week later after professional cleaning and reestablishment of oral hygiene procedures. A total of 180 samples were analyzed with ELISA for levels of IL -6, IL-8 and TNF-a in gingival crevicular fluid. The examination included the mesiobuccal sites of the Ramfjord teeth. Comparisons between and within groups were performed by non-parametric tests (Mann- Withney) and correlations were sought for with Wilcoxon test. Significance was set at p=0.05.

Results:

Results showed significant diferences between the two groups with regard to the plaque and bleeding scores and GCF volume, all of which proved to be more pronounced in old group. With respect to laboratory data, mean cytokine concentrations were in general lower in young group. TNF-a had a steady increase for the adults, which was found to be statistically significant between Days 0 and 21, IL-8 showed a statistically significant decrease at Day 28 in the young group and finally IL-6 showed a fluctuation, which was totally adverse for the two groups at each time point.

Conclusion:

Within the limitations of the present study, age cannot be identified as a factor that strongly affects the cytokine expression and fluctuations even in a well-controlled environment of inflammation, such as experimental gingivitis.
Alumina-on-Polyethylene Bearing Surfaces in Total Hip Arthroplasty
Authors: Yup Lee Jung , Kim Shin-Yoon
Published: March 2010

The long-term durability of polyethylene lining total hip arthroplasty (THA) mainly depends on periprosthetic osteolysis due to wear particles, especially in young active patients. In hip simulator study, reports revealed significant wear reduction of the alumina ceramic-on-polyethylene articulation of THA compared with metal-on-polyethylene bearing surfaces. However, medium to long-term clinical studies of THA using the alumina ceramic-on-polyethylene are few and the reported wear rate of this articulation is variable. We reviewed the advantages and disadvantages of ceramicon- polyethylene articulation in THA, hip simulator study and retrieval study for polyethylene wear,in vivoclinical results of THA using alumina ceramic-on-polyethylene bearing surfaces in the literature, and new trial alumina ceramic-onhighly cross linked polyethylene bearing surfaces.
Trauma Mechanisms and Injuries Associated with Go-Karting
Authors: Eker Hasan H. , Van Lieshout Esther M.M , Hartog Dennis Den , Schipper Inger B
Published: March 2010

Annually, approximately 600 patients seek medical attention after go-kart accidents in the Netherlands. A large variability in injury patterns can be encountered. Knowledge of the trauma mechanisms of go-kart accidents and insight into the associated injuries is limited and requires improvement. Such additional knowledge may lead to customized trauma protocols for patients with a high index of suspicion on go-kart injuries. Research into trauma mechanisms may also lead to implementation of improved or additional safety measures for go-karting, involving both the go-karts itself as well as prerequisites to the go-kart tracks and qualifications for the drivers. The main trauma mechanisms involved in gokart accidents, and three cases to illustrate the variety of injuries are described in the current manuscript.
Negative Staining Technique of Heine for the Detection of Cryptosporidium spp.: A Fast and Simple Screening Technique
Authors: Potters Idzi , Van Esbroeck Marjan
Published: March 2010

Although inexpensive and easy to perform, the negative staining technique of Heine for the detection of Cryptosporidium
spp. has been largely neglected. The lack of familiarity with the negative staining technique, the misconception
that a phase-contrast microscope is indispensible and inferior results due to Köhler-illumination, are possible explanations
for its low popularity. While the modified Ziehl-Neelsen staining technique is still considered the Gold Standard for
the detection of Cryptosporidium spp., the negative staining technique of Heine should be reconsidered as the screening
technique of first choice. Advantages of the negative staining technique of Heine over the modified Ziehl-Neelsen staining
are discussed.
Dimethyl Ether Synthesis over Novel Silicotungstic Acid Incorporated Nanostructured Catalysts
Authors: Ciftci Aysegul , Varisli Dilek , Dogu Timur
Published: March 2010

Dimethyl ether (DME), which is an excellent green diesel-fuel alternate with excellent clean burning properties, is synthesized by dehydration of methanol over novel solid acid catalysts, which are synthesized following a direct hydrothermal route and using silicotungstic acid (STA) as the active compound. These mesoporous silicate structured catalysts have surface area values of 108-393 m2/g, depending upon their W/Si ratio. These catalysts showed very high methanol dehydration activity and also very high DME selectivity values, approaching 100%. The STA-SiO2 mesoporous nanocomposite catalyst having a W/Si atomic ratio of 0.33 showed the highest activity, with a DME selectivity over 99% and a methanol conversion over 60%, at 250°C and at a space time of 0.27 s.g.cm-3. Effects of W/Si atomic ratio, calcination temperature and the synthesis procedure on the catalytic performance of these novel mesoporous catalytic materials were investigated.
Numerical Simulation of Oscillating Heat Pipe Heat Exchanger
Authors: Chai Benyin , Shao Min , Li Xuanyou , Zhou Shenjie , Shi Yongchun
Published: March 2010

Oscillating heat pipe is a new type high efficiency heat-transfer element. Its development and design attract increasing attention. This paper describes a numerical simulation for investigating on the flow and heat exchange performance of an oscillating heat pipe heat exchanger. The influences of the arrangement of heat pipe, the inlet temperature and the flux of hot air were explored. The results show that the heat exchange of staggered arrangement is more efficient than the aligned one. The influence of temperature difference on the heat exchanger by hot air flux is more than hot air inlet temperature.
Ideas, Institutions, and Welfare Program Typologies: An Analysis of Pensions and Old Age Income Protection Policies in Sub‐Saharan Africa
Authors: Kpessa Michael W.
Published: March 2010

Since the 1980s, social policy research shifted attention from institutional development of welfare programs to what were described as crises of the welfare state in an era of austerity. Much of the scholarly debate in this area had focused on the maturation of welfare programs, especially the post‐war old age income support programs in the advanced industrialized countries to the neglect of social protection in Sub‐Saharan African (SSA) countries. This paper is intended to bring the dynamics of social policy in SSA countries into the comparative welfare dialogue and into the global social security debate in particular. Using a historical institutionalist approach, this study analyzes the trajectories of old age income support development in SSA countries through a careful study of old age income security or protection strategies in the region across time and space. The paper develops ideal typologies for understandings variations and transformations of pensions and old age income provision programs in the region. In doing this, it argues that the ideas and institutions around which recent rounds of pension reforms revolves have always been at both the foreground and background of old age income protection thinking and practices in SSA countries since the pre‐colonial era.
Devolution as a Policy Crucible: The Case of Universal Free School Meals
Authors: Morelli Carlo J , Seaman Paul T.
Published: March 2010

The election of the Scottish government, in May 2007, raised expectations that devolution may at last give rise to a sea change in the development of welfare policy. Certainly, in the areas of education and health the newly elected Scottish National Party (SNP) Scottish government, despite its minority control of the parliament, lost no time in announcing significant changes to previous policies in the areas of hospital closures and primary school class sizes. The proposals to introduce universal free school meals in all primary schools for school children in years one to three from 2010, following a pilot in selected local authorities, was one of these changes. This policy shift is of significance for three reasons. First, the previous executive had explicitly rejected proposals for universal free school meals on two previous occasions. Second, it represented a movement towards universality and away from the strategy of targeting and means‐testing welfare adhered to by both the Westminster UK government and the previous Scottish Executive. As such, therefore, the introduction of universal free school meals marks a significant victory for the campaigning groups behind the move. Finally, and perhaps of still greater significance, the introduction of a pilot scheme for universal provision in England, announced by the Westminster government in September 2008, further highlights one other goal of devolution: that of a potential for policy experimentation and divergence. Universal free school provision may be the first example of devolution providing a crucible for welfare policy for the wider United Kingdom. This paper assesses the extent to which an extension of the entitlement to free school meals is likely to improve the access of free school meals to children from the poorest of households and the extent to which changes in free school meal provision leads to a regionally specific impact on child poverty due to variations of household composition within the English regions and Scotland, Wales and Northern Ireland. In doing so we suggest that evidence for the advantages of universal provision provides a positive example of devolution's potential for acting as a welfare policy crucible.
What Can Be Done about Homelessness and Society's Nimby Attitude?—America Needs a Way to Eliminate the Stigma of Public Housing
Authors: Redd Victoria A.
Published: March 2010

America needs a way to eliminate the stigma of public housing. Lawrence Vale suggests some solutions for America's public housing woes in From the Puritans to the Projects: Public Housing and Public Neighbors. If we provide the public housing, what select few of the poor will be allowed to live there? What types of dwellings will be provided as public housing for the poor? And, will this public housing for the poor be near my neighborhood? More importantly, Vale explains what he believes that housing policymakers need to do to improve on the public housing system. The need of housing is downplayed, and instead, there is a focus on what the purpose behind public housing should be. (Congress intervened and called for public housing authorities “to attract a greater mix of incomes.”) Vale's view of the public housing system is enlightening, realistic, and thought‐provoking.
Book Review of Barack Obama's The Audacity of Hope: Thoughts on Reclaiming the American Dream
Authors: Skidmore Max J.
Published: March 2010

Editor‐in‐Chief Max J. Skidmore reviews Barack Obama's The Audacity of Hope: Thoughts on Reclaiming the American Dream and uncovers possible insights into the president's upcoming poverty agenda both at home and abroad.
Research and development investment strategy and market performance
Authors: Liu Tsung-Chi , Chen Yi-Jen
Published: March 2010

In this study, we aimed to analyze research and development (R&D) business strategy with regard to investment funded by the government or by the business itself in relation to market performance. Because these 2 types of subsidized and nonsubsidized R&D may have important implications
for market performance, it is worth considering their differences. In this paper empirical evidence is provided of the relationships among government-funded R&D, private enterprise-funded R&D, and market performance in innovation projects. Regression analysis was used to test the hypotheses
using a sample of 500 projects. The results indicate that market performance of businesses that fund their own R&D is statistically and significantly greater than that of high investment by government in R&D. Finally, managerial implications and possible future research directions
are discussed.
Qualitative Research Ethics: Enhancing Evidence-Based Practice in Physical Therapy
Authors: Townsend Anne , Cox Susan M. , Li Linda C.
Published: March 2010

Background

Increasing challenges to health care systems and the prominence of patient-centered care and evidence-based practice have fostered the application of qualitative approaches in health care settings, prompting discussions of associated ethical issues in a range of disciplines.

Objectives

The purposes of this work were to identify and describe the application and value of qualitative health research for physical therapy and to identify ethical considerations in a qualitative research study.

Design

This was a qualitative interview study with telephone follow-ups.

Methods

Forty-six participants were interviewed about their early experiences with rheumatoid arthritis. They also were asked what motivated them to volunteer for the study. To inform the discussion of ethics in qualitative health research, this study drew on the in-depth interviews, took a descriptive approach to the data, and applied the traditional ethical principles of autonomy, justice, and beneficence to the study process.

Results

Ethical issues emerged in this qualitative health research study that were both similar to and different from those that exist in a positivist paradigm (eg, clinical research). With flexibility and latitude, the traditional principle approach can be applied usefully to qualitative health research.

Conclusions

These findings build on previous research and discussion in physical therapy and other disciplines that urge a flexible approach to qualitative research ethics and recognize that ethics are embedded in an unfolding research process involving the role of the subjective researcher and an active participant. We suggest reflexivity as a way to recognize ethical moments throughout qualitative research and to help build methodological and ethical rigor in research relevant to physical therapist practice.
Effect of Intensive Outpatient Physical Training on Gait Performance and Cardiovascular Health in People With Hemiparesis After Stroke
Authors: Jørgensen Jørgen Roed , Bech-Pedersen Daniel Thue , Zeeman Peter , Sørensen Janne , Andersen Lars L. , Schönberger Michael
Published: March 2010

Background

Stroke can result in severe motor deficits, and many people who have survived a stroke have poor cardiovascular fitness, with potentially disabling effects on daily life.

Objective

The objective of this study was to evaluate the impact of intensive physical training on gait performance and cardiovascular health parameters in people with stroke in the chronic stage.

Design

This was a single-group, pretest-posttest experimental study.

Methods

Fourteen people with hemiparesis after cerebrovascular injury (mean age=58.4 years, mean time since injury=25 months) participated in a 12-week training intervention, 5 times per week for 1.5 hours per session. The intervention consisted of high-intensity, body-weight–supported treadmill training; progressive resistance strength training; and aerobic exercise. The main outcome measures were gait performance (Six-Minute Walk Test, 10-Meter Walk Test, and aerobic capacity) and parameters of cardiovascular health (systolic and diastolic blood pressures, body mass index, and resting heart rate).

Results

Significant improvements in all main outcome parameters were observed in response to the intervention. Gait speed during the Six-Minute Walk Test increased 62%, and systolic and diastolic blood pressures decreased 10% and 11%, respectively. Weekly testing of walking speed showed that most of the increase in the walking speed occurred in the first 8 weeks of training. Correlation analyses showed that improvements were unrelated to age, chronicity, or level of functioning.

Conclusions

High-intensity physical training for people with stroke in the chronic stage increased walking speed regardless of chronicity, age, or level of functioning. Further studies should investigate the intervention duration needed to reach the full potential of gait recovery.
A Simple Clinical Scale to Stratify Risk of Recurrent Falls in Community-Dwelling Adults Aged 65 Years and Older
Authors: Buatois Severine , Perret-Guillaume Christine , Gueguen Rene , Miget Patrick , Vançon Guy , Perrin Philippe , Benetos Athanase
Published: March 2010

Background

Correct identification of people at risk for recurrent falls facilitates the establishment of preventive and rehabilitative strategies in older adults.

Objective

The purposes of this study were: (1) to develop and validate a simple clinical scale to stratify risk for recurrent falls in community-dwelling elderly people based on easily obtained social and clinical items and (2) to evaluate the added value of 3 clinical balance tests in predicting this risk.

Design

This was a prospective measurement study.

Methods

A population of 1,618 community-dwelling people over 65 years of age underwent a health checkup, including performance of 3 clinical balance tests: the One-Leg-Balance Test, the Timed “Up & Go” Test, and the Five-Times-Sit-to-Stand Test. Falls were recorded using a self-administered questionnaire that was completed a mean (SD) of 25±5 months after the visit. Participants were randomly divided into either group A (n=999), which was used to develop the scale, or group B (n=619), which was used to prospectively validate the scale.

Results

Logistic regression analysis identified 4 variables that independently predicted recurrent falls in group A: history of falls, living alone, taking ≥4 medications per day, and female sex. Thereafter, 3 risk categories of recurrent falls (low, moderate, and high) were determined. Predicted probability of recurrent falls increased from 4.1% to 30.1% between the first and third categories. This scale subsequently was validated with great accuracy in group B. Only the Five-Times-Sit-to-Stand Test provided added value in the estimation of risk for recurrent falls, especially for the participants who were at moderate risk, in whom failure on the test (duration of >15 seconds) doubled the risk.

Limitations

Falls were assessed only once, and length of follow-up was heterogeneous (18–36 months).

Conclusions

Clinicians could easily classify older patients in low-, moderate-, or high-risk groups of recurrent falls by using 4 easy-to-obtain items. The Five-Times-Sit-to-Stand Test provides added value to stratify risk for falls in people at moderate risk.