bluuebunny/crossref_metadata_2025 huggingface dataset:
Switchgrass Winter Yield, Year‐Round Elemental Concentrations, and Associated Soil Nutrients in a Zero Input Environment
Authors: Makaju S. O. , Wu Y. Q. , Zhang H. , Kakani V. G. , Taliaferro C. M. , Anderson M. P.
Published: February 2013

The maximum biomass yield of switchgrass (Panicum virgatum L.) usually is achieved with one seasonal autumn harvest. However, information is limited on the influences of winter harvesting on annual biomass yield and on quality parameters impacting conversion into bioethanol. Accordingly, the objectives of this study were to assess: (i) yield of standing field cured biomass at monthly intervals through winter, (ii) year‐round elemental composition of biomass, and (iii) associated year‐round soil nutrient status. An unfertilized ‘Kanlow’ switchgrass planting established in 1998 was used for this study conducted from November 2007 to October 2010. The experimental treatment was monthly harvest from November to the following March and year‐round monthly sampling of biomass (except April) and soil for chemical analyses. The 3‐yr mean dry matter yield of winter harvests was 5.94Mg ha−1, ranging from 3.88 Mg ha−1 in the winter of 2007–2008 to 7.55 Mg ha−1 in 2009–2010. Monthly biomass yield differences were significant in Years 1 and 3 but not in Year 2. Concentrations of biomass elements and soil nutrients changed with various degrees over the 3 yr. Concentrations of ash, cell wall components, and mineral nutrients, except P, K, and S, did not change appreciably across winter months. Early winter harvests resulted in less yield loss compared to late winter harvests. These findings will be valuable in harvest management for switchgrass biomass production.
Intraspecific and Interspecific Competition in Sweet Corn
Authors: Williams M. M. , Boydston R. A.
Published: February 2013

Competition among crop plants (i.e., intraspecific) and between crop and weed plants (i.e., interspecific) likely co‐occurs in many sweet corn (Zea mays L.) fields; however, a fundamental understanding of the extent to which the crop is affected by the combination of these stresses is unknown. The objective of this work was to identify the extent to which seeding level influences the crop’s tolerance to weed competition in terms of crop development, yield, and profitability. In field research in Illinois and Washington, two hybrids with different levels of tolerance to weed competition were planted each of 2 yr at five seeding levels each year and grown in the presence and absence of wild‐proso millet (Panicum miliaceum L.). The crop’s ability to tolerate intraspecific and interspecific competition was additive, as evidenced by no significant interaction between seeding level and weed competition for thermal time to mid‐silk, marketable ear number, marketable ear mass, and gross profit margin to the processor. Losses in gross profit margin due to weed competition alone ranged from $2,400 to $8,100 ha−1. Hybrids used in this work showed differential tolerance to interspecific competition, but of the seeding levels tested, neither hybrid was consistently more tolerant to intraspecific competition. Across years and hybrids, the seeding level that consistently did not delay silking but maximized marketable ear number, marketable ear mass, and gross profit margin to the processor was 70,000 and 88,200 ha−1 in Illinois and Washington, respectively. Improving weed management efficacy and genetic tolerance to competition offer two approaches to improving sweet corn productivity.
Diminishing marginal returns for sensor networks in a water distribution system
Authors: Shen Hailiang , McBean Edward
Published: February 2013

With increasing interest in the implementation/functionality of a contaminant warning system for water distribution systems, questions exist over the application to a real distribution system. A methodology is described to assess the impacts of changes in the numbers of sensors, on the time delay required to detect a contaminant intrusion event and to maximize sensor detection redundancy as protection against false positives. The methodology is used to explore the point of diminishing marginal return of detection likelihood, and the average time delay of detected intrusion events. Pareto front performance improvement with increasing numbers of sensors (from 2 through 50) is characterized through a case study application to the City of Guelph water distribution system (WDS). The results provide a methodology for utilities to employ for decisions on the number of sensors to use for a system. Within the two scenarios applied, five and four sensors are shown to be the point of diminishing marginal return for Guelph WDS in terms of the Pareto front performance improvement, detection likelihood, and the average time delay for the case study. Nevertheless, given that the timeframe to detect a contamination event may be lengthy, placing more sensors than the point of diminishing marginal return may be appropriate.
Regionalization of hydrological model parameters using data depth
Authors: Bárdossy András , Singh Shailesh Kumar
Published: February 2013

The parameters of hydrological models with no or short discharge records can only be estimated using regional information. We can assume that catchments with similar characteristics show a similar hydrological behaviour. A regionalization of hydrological model parameters on the basis of catchment characteristics is therefore plausible. However, due to the non-uniqueness of the rainfall/runoff model parameters (equifinality), a procedure of a regional parameter estimation by model calibration and a subsequent fit of a regional function is not appropriate. In this paper, a different procedure based on the depth function and convex combinations of model parameters is introduced. Catchment characteristics to be used for regionalization can be identified by the same procedure. Regionalization is then performed using different approaches: multiple linear regression using the deepest parameter sets and convex combinations. The assessment of the quality of the regionalized models is also discussed. An example of 28 British catchments illustrates the methodology.
Predictions in a data-sparse region using a regionalized grid-based hydrologic model driven by remotely sensed data
Authors: Samaniego Luis , Kumar Rohini , Jackisch Conrad
Published: February 2013

The goal of this study was to assess the feasibility of using Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS) products to drive a mesoscale hydrologic model (mHM) in a poorly gauged basin. Other remotely sensed products such as LandSat and Shuttle Radar Topography Mission (SRTM) were also used to complement the local geoinformation. For this purpose, three data blending techniques that combine satellite with in situ observations were implemented and evaluated in the Mod basin (512 km2) in India. The climate of the basin is semi-arid and monsoon-dominated. The rainfall gauging network comprised six stations with daily records spanning 9 years. Daily discharge time series was only 4 years long and incomplete. Lumped and distributed versions of mHM were evaluated. Parameters of the lumped version were obtained through calibration. A multiscale regionalization technique was used to parameterize the distributed version using global parameters from other gauged basins. Both mHM versions were evaluated during six monsoon seasons. Results of numerical experiments indicated that driving mHM with satellite-based products is possible and promising. The distributed model with regionalized parameters was at least 20% more efficient than that of its lumped version. Initialization conditions must be carefully considered when the model is only driven by remotely sensed inputs.
Frequency of episodic stratification in the near surface of Lake Opeongo and other small lakes
Authors: Pernica Patricia , Wells Mathew
Published: February 2013

Wind-driven mixing in the epilimnion of a deep lake can be suppressed when there is a weak near surface stratification, which occurs frequently during periods of strong solar heating and weak winds. Using data from a vertical chain of fast response thermistors, we analyze the frequency of near surface stratification in the top 2 meters of the epilimnion in Lake Opeongo, Ontario for the periods between May and August in 2009 and 2010. Near surface thermoclines (as defined by dT/dz > 0.2 °C m−1 between 1 and 2 m) occur for 24% of the sampling period in 2009, 37% of the sampling period in 2010 and correspond to periods of high values of gradient Richardson number. During daytime the epilimnion is stratified up to 45% of the time. At night, cooling generally leads to a more isothermal profile, but near surface thermoclines still form at least 20% of the time. Extended periods of near surface stratification (>1 h), account for more than 80% of the stratified period. We compare these findings with previous observations from the Experimental Lakes Area in Northern Ontario, and discuss the biological implications of episodic stratification.
Summary performance of the Estuary and Lake Computer Model (ELCOM): application in the Laurentian and other Great Lakes
Authors: Leon Luis F. , Antenucci Jason P. , Rao Yerubandi R. , McCrimmon Craig
Published: February 2013

The use of sophisticated three-dimensional (3D) hydrodynamic models is often required to simulate the spatial and temporal variability of water quality in large lakes. Recently, coupled lake–atmosphere models have also been developed to resolve the spatial distribution of the thermal behavior in lakes and to assess the feedback mechanisms at the air–water interface. In the studies summarized in this paper, the 3D Estuary and Lake Computer Model (ELCOM) acts as the hydrodynamic driver that provides temperature, salinity, and the transport fields that, if coupled with the Computational Aquatic Ecosystem Dynamics Model (CAEDYM), simulates nutrients, phytoplankton, zooplankton, and benthic habitat. This study presents a summary of the performance of ELCOM, and in an indirect form, serves as well as a corroboration of the strength or weakness of the coupled modeling and its ability to reproduce the thermal structure and circulation patterns, with examples from the Laurentian Great Lakes (Erie and Ontario), Northern Great Lakes (Great Slave Lake and Great Bear Lake), and Lake Winnipeg in Central Canada.
Decadal and seasonal water quality trends downstream of urban and rural areas in southern Alberta rivers
Authors: Turnbull B. , Ryan M. C.
Published: February 2013

Seasonal and long-term water quality changes downstream of urban and agricultural land uses were compared using chloride, fecal coliform (FC), Escherichia coli and discharge from five long-term river monitoring sites in the Bow and Oldman watersheds in southern Alberta. Water quality data from up- and downstream locations of two major urban centers (Calgary and Lethbridge) and single sampling locations downstream of three agricultural sites were evaluated. Significant monotonic, decadal increases in chloride mass fluxes observed downstream of both urban areas were consistent with increasing chloride fluxes in wastewater effluent from increasing populations. Significant step function decreases in FC concentrations downstream of the two urban centers (89% at Calgary, 70% at Lethbridge) observed after UV disinfection were introduced at upstream wastewater treatment plants, suggesting wastewater disinfection improved river water quality. Significant monotonic decreases in pathogen indicators were found at only one of the three agricultural sampling locations. Seasonal variations in indicator bacteria were consistent with a constant source at the urban downstream sites, while variable seasonal loading patterns at the agricultural sites were attributed to seasonally changing land use. This suggests that the urban centers are more significantly mitigating pathogens in rivers than rural areas despite their significant growth.
An oscillating bottom boundary layer connects the littoral and pelagic regions of Lake Opeongo, Canada
Authors: Coman Melissa Anne , Wells Mathew Graeme
Published: February 2013

The movement of a thermocline can drive strong benthic currents, which can transport nutrients from sediments into the water column via pore water advection or sediment resuspension. We report field observations of near-shore benthic velocities and offshore thermocline movements in Lake Opeongo; a medium-sized lake typical of the Canadian Shield. We find that during large thermocline deflections there are sustained currents >6 cm s−1 in the near-shore benthic layer. The mean current was 1.75 cm s−1 and the maximum current is 10.3 cm s−1. At our site, the net transport is offshore even though the thermocline oscillates up and down so that currents are sometimes upslope and inshore. We estimate the excursion length of a water parcel over the 31-day deployment period, and determine that the mean daily excursion length is 630 m, with the maximum value being 2 km offshore. Given that the south arm of Lake Opeongo is 6 km long and 0.6 km wide, the predicted excursion length of water implies that there is strong connectivity between the sediment in the littoral zone, and the metalimnetic waters offshore. As Lake Opeongo is oligotrophic, any nutrient pulses from the sediment will be quickly taken up by the plankton.
Identifying parameter sensitivity in a water quality model of a reservoir
Authors: Huang Yongtai , Pierson Don
Published: February 2013

Sensitivity analysis can provide useful insights into how a model responds to the variations in its parameter values (i.e. coefficients). The results can be very helpful for model calibration, refinement and application. A one-dimensional model has been set up to simulate the hydrothermal and water quality conditions of Cannonsville Reservoir, which provides water supply for New York City. This paper aims at identifying the most influential parameters in the model through sensitivity analysis. Firstly, the Morris method (a screening method) is used to identify influential parameters. It is found that 18 parameters are important in simulations of variables that include temperature, dissolved oxygen (DO), total phosphorus (TP) and chlorophyll a (Chla). Secondly, the method is enhanced to investigate the global sensitivity of the parameters. It highlights 20 parameters that are sensitive in the simulations of the above-mentioned variables. The 18 parameters identified by the original Morris method are among the 20 parameters and the other two parameters are not very sensitive. The results show that similar results can be obtained through the original and enhanced Morris methods, although they each have their own strengths and weaknesses.
Leachate dissolved organic matter characterization using spectroscopic methods
Authors: Yunus Anika , Smallman David J. , Stringfellow Anne , Beaven Richard , Powrie William
Published: February 2013

This study investigated the use of ultraviolet (UV) and fluorescence spectroscopy to monitor the changes in biodegradability of dissolved organic matter (DOM) in landfill leachates. Experiments to investigate aerobic biodegradation of leachate DOM were carried out using untreated and treated leachate samples collected from two UK municipal solid waste landfills, L1 and L2. Leachate samples collected at different stages of the aerobic treatment processes were characterized by conventional methods (chemical oxygen demand (COD) and dissolved organic carbon content (DOC)) and also by UV spectroscopy and fluorescence excitation-emission matrix. The laboratory-scale aerobic treatment system achieved reductions in COD and DOC in all of the leachates. Results obtained from UV spectrophotometry indicated that the aromatic character of the leachate decreased during aerobic biodegradation. Additionally, the fluorescence intensity of the leachates decreased to various extents, suggesting degradation of humic, fulvic or protein-like structures during biodegradation. Initial results showed strong relations between fluorescent DOC and fluorescent COD and suggest that the strength of these correlations could be a useful tool in distinguishing sources and biodegradability of DOC cheaply and quickly, although further research using different types of leachates is required.
An evaluation of MBR and conventional pretreatment for reverse osmosis for water reclamation
Authors: Xu J. , Kent F. C. , Farahbakhsh K.
Published: February 2013

Two wastewater polishing systems were compared in terms of their ability to protect downstream reverse osmosis (RO) processes. A conventional full-scale wastewater treatment system with primary and secondary treatment followed by rotating biological contactors (RBC) and sand filtration were compared in a side-by-side study with a pilot-scale membrane bioreactor (MBR). Effluent from the two pretreatment trains was sent to two identical RO pilot systems. The effluent water quality of the two systems was compared as well as the RO performance. The MBR pretreatment provided effluent with a turbidity (0.11 NTU) that was more than five times lower than that of the conventional system (0.58 NTU). The fouling rate of the RO system with MBR pretreatment was 50–67% of the value found for the RO system with conventional pretreatment and the difference in turbidity values was identified as the major source of this large difference. The RO effluent quality of both systems was excellent, with similar overall removals in both systems. The study emphasizes the importance of removing particulate matter for the prevention of RO fouling within water reclamation.
Fish (Labeo rohita) scales as a new biosorbent for removal of textile dyes from aqueous solutions
Authors: Chakraborty Sagnik , Chowdhury Shamik , Saha Papita Das
Published: February 2013

The feasibility of utilizing fish scales as a new biosorbent for removal of textile dyes, namely crystal violet (CV) and methylene blue (MB), from their aqueous solutions was investigated in a batch system. Experiments were conducted as a function of initial solution pH (2–10), contact time (0–180 min), biosorbent dose (0.5–5 g) and temperature (293–313 K). The Langmuir isotherm model showed excellent fit to the equilibrium biosorption data of both CV and MB. The maximum dye biosorption capacity of fish scale was calculated as 74.39 and 58.67 mg g−1 for CV and MB, respectively, at 313 K. Biosorption phenomena of CV and MB by fish scales followed pseudo-second-order kinetics. Activation energy calculated by using the Arrhenius equation suggested the chemisorption nature of the biosorption processes. A thermodynamic assessment indicated the spontaneous and endothermic nature of biosorption of the textile dyes. It could be concluded that fish scales may be used as an inexpensive and effective biosorbent for removal of dyes from aqueous solutions.
Pilot scale evaluation of biofiltration as an innovative pre-treatment for ultrafiltration membranes for drinking water treatment
Authors: Huck P. M. , Peldszus S. , Hallé C. , Ruiz H. , Jin X. , Van Dyke M. , Amy G. , Uhl W. , Theodoulou M. , Mosqueda-Jimenez D. B.
Published: February 2013

Fouling remains one of the major constraints on the use of low pressure membranes in drinking water treatment. Work over the last few years has shown the importance of biopolymers (carbohydrates and protein-like material) as foulants for ultrafiltration (UF) membranes. The purpose of this study was to investigate at pilot scale the use of rapid biofiltration (without prior coagulation or ozone addition) as an innovative pretreatment to reduce fouling of UF membranes. The investigation was carried out on a water with a higher than average DOC and significant temperature variation. The biofilters, each operated at a hydraulic loading of 5 m/h, had empty bed contact times of 5, 10 and 15 minutes. The membrane unit was operated at a flux equivalent to 60 LMH at 20°C. The investigation confirmed the encouraging results obtained in an earlier smaller scale study with essentially the same water. Increased biofiltration contact time (i.e. increased bed depth) led to lower rates of hydraulically irreversible fouling. The initial biofiltration backwash procedure, involving air scour as is common in chemically assisted filtration, led in some cases to an increased rate of membrane fouling immediately after the backwash. An alternative backwashing strategy was developed, however the feasibility of operating with this approach over very long periods of time needs to be confirmed. To assist in full-scale implementation of this “green” and simple pretreatment, the design and operating conditions for the biofilters should be optimized for various types of waters. It is expected that biofiltration pretreatment will be of particular interest for small and/or isolated systems where a higher initial capital cost may be acceptable because of operational simplicity and reduced chemical requirements.
Preparation of TiO2-diatomite composites by ball-milling and its photocatalytic degradation of methyl orange
Authors: Deng Yanxi , Wang Xuming , Yin Jinfeng , Li Yanfeng , Ding Hao , Chang Fei
Published: February 2013

TiO2-diatomite composites were prepared using a two–stage ball-milling technique and they were subsequently characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and FTIR, showing that nanotitania had been successfully supported on the surface of diatomite. The as-prepared TiO2–diatomite composites were used to decompose methyl orange (MO). Good degradation efficiency was observed. The effects of milling conditions, such as milling time of diatomite suspension, the diatomite particle concentration in suspension, weight ratio of ball-to-powder, milling time of the mixed TiO2-diatomite suspension and dosage of titania, on photocatalytic degradation performance were systematically examined for the sake of achieving the best efficiency.
Degradation of propoxycarbazone-sodium with advanced oxidation processes
Authors: Dulov A. , Dulova N. , Veressinina Y. , Trapido M.
Published: February 2013

The degradation of propoxycarbazone-sodium, an active component of commercial herbicide, in aqueous solution with ozone, UV photolysis and advanced oxidation processes: O3/UV, O3/UV/H2O2, H2O2/UV, and the Fenton process was studied. All these methods of degradation proved feasible. The kinetics of propoxycarbazone-sodium degradation in water followed the pseudo-first order equation for all studied processes except the Fenton treatment. The application of schemes with ozone demonstrated low pseudo-first order rate constants within the range of 10−4 s−1. Addition of UV radiation to the processes improved the removal of propoxycarbazone-sodium and increased the pseudo-first order rate constants to 10−3 s−1. The Fenton process was the most efficient and resulted in 5 and 60 s of half-life and 90% conversion time of propoxycarbazone-sodium, respectively, at 14 mM H2O2 concentration. UV treatment and the Fenton process may be recommended for practical application in decontamination of water or wastewater.
Effects of Oral Sodium Bicarbonate in Patients with CKD
Authors: Abramowitz Matthew K. , Melamed Michal L. , Bauer Carolyn , Raff Amanda C. , Hostetter Thomas H.
Published: February 2013

Background and objectives

Metabolic acidosis contributes to muscle breakdown in patients with CKD, but whether its treatment improves functional outcomes is unknown. The choice of dose and tolerability of high doses remain unclear. In CKD patients with mild acidosis, this study evaluated the dose–response relationship of alkali with serum bicarbonate, its side effect profile, and its effect on muscle strength.

Design, setting, participants, & measurements

In this single-blinded pilot study from March of 2009 to August of 2010, 20 adults with estimated GFR 15–45 ml/min per 1.73 m2 and serum bicarbonate 20–24 mEq/L were treated during successive 2-week periods with placebo followed by escalating oral NaHCO3 doses (0.3, 0.6, and 1.0 mEq/kg per day). At each visit, handgrip strength and time required to complete 5 and 10 repetitions of a sit-to-stand test were measured.

Results

Each 0.1 mEq/kg per day increase in dose produced a 0.33 mEq/L (95% confidence interval=0.23–0.43 mEq/L) higher serum bicarbonate. Sit-to-stand time improved after 6 weeks of oral NaHCO3 (23.8±1.4 versus 22.2±1.6 seconds for 10 repetitions, P=0.002), and urinary nitrogen excretion decreased (−0.70 g/g creatinine [95% confidence interval=−1.11 to −0.30] per 0.1 mEq/kg per day higher dose). No statistically significant change was seen in handgrip strength (29.5±9.6 versus 28.4±9.4 kg, P=0.12). Higher NaHCO3 doses were not associated with increased BP or greater edema.

Conclusions

NaHCO3 supplementation produces a dose-dependent increase in serum bicarbonate and improves lower extremity muscle strength after a short-term intervention in CKD patients with mild acidosis. Long-term studies are needed to determine if this finding translates into improved functional status.
Determination of feasibility and advantages of using additional turbines to reduce energy consumption and CO2 emission of a distillation column
Authors: Svang-Ariyaskul Apichit , Chaireongsirikul Thanapat
Published: February 2013

Distillation is a process that consumes an extensive amount of energy and
emits an enormous amount of CO2. It is attractive to reduce the energy
consumption and CO2 emission for distillation. A new design of distillation
is proposed by adding turbines in the vapor process streams before the
condenser and after a reboiler to produce domestic electricity. As a result,
this new design helps in reducing energy consumption and CO2 emission. The
key variables are the distillate to feed ratio and the reflux ratio because
they are the direct factors that control the vapor flowrates supplying the
turbines. The distillation of an alkane mixture of C4 - C8 commonly found in
a petroleum refinery was used as a test model to prove the process
feasibility. The energy consumption and CO2 emission of the new process are
reduced to 0.93 - 0.96 and 0.89 - 0.90 of the conventional process,
respectively. This new design increases process efficiency in terms of second
law efficiency by reducing the entropy generation from the conventional
distillation at low distillate to feed ratios and reflux ratios. The
distillation with additional turbines is promising to reduce energy
consumption and CO2 emission and to increase process efficiency.
Desorption of 137Cs from Homalothecium sericeum (Hedw.) Schim. moss using weakly acid solutions
Authors: Cuculovic Ana , Veselinovic Dragan
Published: February 2013

Desorption of 137Cs from Homalothecium sericeum (Hedw.) Schim. moss was
performed using five consecutive desorptions with five identical solution
volumes. The following solutions were used for desorption: H2SO4, HNO3 and
their mixture H2SO4-HNO3, with pH values of 4.61; 5.15 and 5.75; and also
distilled water pH 6,50. After five consecutive desorptions from 22.8%
(solution H2SO4-HNO3 pH 5.75) to 33.2% (solution H2SO4-HNO3 pH 4.60) of 137Cs
was desorbed by the sorbed acid, while by distilled water 31.3% of 137Cs was
desorbed. The highest amount of 137Cs is desorbed by the first desorption,
from 9.0% to 17.9%. Mean values of the total percentage of desorbed 137Cs
from moss are similar: for solution H2SO4 28.8%; HNO3 25.7% and H2SO4-HNO3
28.6%, that indicates that NO3- and SO42- anions do not have an influence on
Cs+ desorption. The used pH values of solutions do not significantly
influence 137Cs desorption from moss. After five consecutive desorptions
137Cs is not significantly desorbed from moss. In the pH interval of 4.61 to
6.50 the desorbed substances are H2O and H+ ions, while SO42- and NO3- ions
have a smaller influence. There are two sorption points, i.e. two sorption
types where one is dominant.
Variable neighborhood search for maximum diverse grouping problem
Authors: Urosevic Dragan
Published: February 2013

This paper presents a general variable neighborhood search (GVNS) heuristic
for solving the maximum diverse grouping problem. Extensive computational
experiments performed on a series of large random graphs as well as on
several instances of the maximum diversity problem taken from the literature
show that the results obtained by GVNS consistently outperform the best
heuristics from the literature.
Detectable Subclinical Myocardial Necrosis Is Associated With Cardiovascular Risk in Stable Patients With Diabetes
Authors: Tang W.H. Wilson , Wu Yuping , Britt Earl B. , Iqbal Naveed , Hazen Stanley L.
Published: February 2013

OBJECTIVE

To investigate the relationship between different degrees of subclinical myocardial necrosis, glycemic control, and long-term adverse clinical outcomes within a stable patient population with diabetes mellitus.

RESEARCH DESIGN AND METHODS

We examined 1,275 stable patients with diabetes mellitus undergoing elective diagnostic coronary angiography with cardiac troponin I (cTnI) levels below the diagnostic cut-off for defining myocardial infarction (MI) (<0.03 ng/mL). The relationship of subclinical myocardial necrosis (cTnI 0.009–0.029 ng/mL) with incident major adverse cardiovascular events (MACE; defined as any death, MI, or stroke) over 3 years of follow-up was examined.

RESULTS

Subclinical myocardial necrosis was observed in 22% of patients. A strong association was observed between the magnitude of subclinical myocardial necrosis and risk of 3-year incident MACE (hazard ratio, 1.98; 95% confidence interval, 1.48–2.65; P < 0.001) and remained statistically significant even after adjustment for traditional risk factors, high-sensitivity C-reactive protein, and creatinine clearance. Only a weak correlation was observed between the presence of subclinical myocardial necrosis and either glycemic control (r = 0.06; P = 0.044 for hemoglobin A1c versus cTnI) or insulin resistance (r = 0.04; P = 0.094 for glucose-to-insulin ratio versus cTnI).

CONCLUSIONS

The presence of detectable subclinical myocardial necrosis in stable patients with diabetes mellitus is associated with heightened long-term risk for MACE, independent of traditional risk factors and glycemic control.
Systemic Oxidative Stress Is Associated With Lower Aerobic Capacity and Impaired Skeletal Muscle Energy Metabolism in Patients With Metabolic Syndrome
Authors: Yokota Takashi , Kinugawa Shintaro , Yamato Mayumi , Hirabayashi Kagami , Suga Tadashi , Takada Shingo , Harada Kuniaki , Morita Noriteru , Oyama-Manabe Noriko , Kikuchi Yasuka , Okita Koichi , Tsutsui Hiroyuki
Published: February 2013

OBJECTIVE

Systemic oxidative stress is associated with insulin resistance and obesity. We tested the hypothesis that systemic oxidative stress is linked to lower aerobic capacity and skeletal muscle dysfunction in metabolic syndrome (MetS).

RESEARCH DESIGN AND METHODS

The incremental exercise testing with cycle ergometer was performed in 14 male patients with MetS and 13 age-, sex-, and activity-matched healthy subjects. Systemic lipid peroxidation was assessed by serum thiobarbituric acid reactive substances (TBARS), and systemic antioxidant defense capacity was assessed by serum total thiols and enzymatic activity of superoxide dismutase (SOD). To assess skeletal muscle energy metabolism, we measured high-energy phosphates in the calf muscle during plantar flexion exercise and intramyocellular lipid (IMCL) in the resting leg muscle, using 31P- and 1proton-magnetic resonance spectroscopy, respectively.

RESULTS

Serum TBARS were elevated (12.4 ± 7.1 vs. 3.7 ± 1.1 μmol/L; P < 0.01), and serum total thiols and SOD activity were decreased (290.8 ± 51.2 vs. 398.7 ± 105.2 μmol/L, P < 0.01; and 22.2 ± 8.4 vs. 31.5 ± 8.5 units/L, P < 0.05, respectively) in patients with MetS compared with healthy subjects. Peak VO2 and anaerobic threshold normalized to body weight were significantly lower in MetS patients by 25 and 31%, respectively, and inversely correlated with serum TBARS (r = −0.49 and r = −0.50, respectively). Moreover, muscle phosphocreatine loss during exercise was 1.4-fold greater in patients with MetS (P < 0.05), and IMCL content was 2.9-fold higher in patients with MetS (P < 0.01), indicating impaired skeletal muscle energy metabolism, and these indices positively correlated with serum TBARS (r = 0.45 and r = 0.63, respectively).

CONCLUSIONS

Systemic oxidative stress was associated with lower aerobic capacity and impaired skeletal muscle energy metabolism in patients with MetS.
Determinants of Maternal Triglycerides in Women With Gestational Diabetes Mellitus in the Metformin in Gestational Diabetes (MiG) Study
Authors: Barrett Helen L. , Dekker Nitert Marloes , Jones Lee , O’Rourke Peter , Lust Karin , Gatford Kathryn L. , De Blasio Miles J. , Coat Suzette , Owens Julie A. , Hague William M. , McIntyre H. David , Callaway Leonie , Rowan Janet
Published: February 2013

OBJECTIVE

Factors associated with increasing maternal triglyceride concentrations in late pregnancy include gestational age, obesity, preeclampsia, and altered glucose metabolism. In a subgroup of women in the Metformin in Gestational Diabetes (MiG) trial, maternal plasma triglycerides increased more between enrollment (30 weeks) and 36 weeks in those treated with metformin compared with insulin. The aim of this study was to explain this finding by examining factors potentially related to triglycerides in these women.

RESEARCH DESIGN AND METHODS

Of the 733 women randomized to metformin or insulin in the MiG trial, 432 (219 metformin and 213 insulin) had fasting plasma triglycerides measured at enrollment and at 36 weeks. Factors associated with maternal triglycerides were assessed using general linear modeling.

RESULTS

Mean plasma triglyceride concentrations were 2.43 (95% CI 2.35–2.51) mmol/L at enrollment. Triglycerides were higher at 36 weeks in women randomized to metformin (2.94 [2.80–3.08] mmol/L; +23.13% [18.72–27.53%]) than insulin (2.65 [2.54–2.77] mmol/L, P = 0.002; +14.36% [10.91–17.82%], P = 0.002). At 36 weeks, triglycerides were associated with HbA1c (P = 0.03), ethnicity (P = 0.001), and treatment allocation (P = 0.005). In insulin-treated women, 36-week triglycerides were associated with 36-week HbA1c (P = 0.02), and in metformin-treated women, they were related to ethnicity.

CONCLUSIONS

At 36 weeks, maternal triglycerides were related to glucose control in women treated with insulin and ethnicity in women treated with metformin. Whether there are ethnicity-related dietary changes or differences in metformin response that alter the relationship between glucose control and triglycerides requires further study.
Utility of a Partial Autopsy: A Case Report of Congenital Laryngeal Atresia
Authors: Savage Erica C. , Robinson Robert A. , Kirby Patricia
Published: February 2013

Laryngeal atresia is a rare congenital anomaly that is fatal if not quickly diagnosed at birth. Here we report a case of unexpected congenital laryngeal atresia and esophageal atresia in a preterm male infant, in whom prenatal ultrasonic findings were limited to polyhydramnios and duodenal atresia. Attempts at intubation and emergent tracheotomy were unsuccessful. A diagnosis of congenital laryngeal atresia with esophageal atresia was made during a restricted autopsy (limited to the neck). In an era of declining autopsy rates nationwide, this case emphasizes the value of limited autopsy examinations, focused on the region of interest.
Advances in the Genetics and Epigenetics of Neurodegenerative Diseases
Authors: Coppedè Fabio
Published: February 2013

Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Huntington’s disease (HD) represent four of the major neurodegenerative diseases. AD, PD and ALS are complex disorders including both Mendelian and sporadic forms. Studies on families with these diseases led to the identification of several genes and pathways responsible for the familial forms. Those studies have been paralleled by hundreds of genetic association studies, including genome-wide screenings, in order to identify genes likely contributing to the sporadic forms. HD is a monogenic disorder caused by a trinucleotide repeat expansion in the causative gene. Increasing evidence points to an epigenetic contribution to neurodegeneration, suggesting that DNA methylation, histone tail modifications and RNA mediated mechanisms might contribute to the onset and progression of all the above diseases. In addition, epigenetic drugs are promising for the restoration of memory and motor impairments in animal models of the diseases. The aim of this review article is to provide an updated overview of the genetics and epigenetics of these major neurodegenerative disorders.
Simultaneous determination of cytochrome P450 1A, 2A and 3A activities in porcine liver microsomes
Authors: Johansson Monika , Tomankova Jana , Li Shengjie , Zamaratskaia Galia
Published: February 2013

The aim of this study was to develop a robust method for the simultaneous determination of the activities of three porcine CYP450 enzymes in hepatic microsomes. A cocktail consisting of three selective CYP450 probe substrates, 7-ethoxyresorufin (CYP1A), coumarin (CYP2A) and 7-benzyloxy-4-trifluoromethylcoumarin (BFC; CYP3A), was incubated with porcine liver microsomes. The presence of 7-ethoxyresorufin appears to significantly influence the kinetics of coumarin hydroxylation and BFC O-debenzylation. These results indicate that the use of 7-ethoxyresorufin in substrate cocktails together with coumarin and BFC should be avoided.
Sex differences in endothelial function of aged hypertriglyceridemic rats – effect of atorvastatin treatment
Authors: Sotnikova Ruzena , Bacova Barbora , Vlkovicova Jana , Navarova Jana , Tribulova Narcis
Published: February 2013

The aim of the study was to test the hypothesis that the effect of atorvastatin on endothelium-dependent relaxation of the superior mesenteric artery (SMA) may differ in male vs. female aged hypertriglyceridemic rats (HTGs). Experiments were performed on 11-month-old male and female Prague hereditary HTGs. Atorvastatin (ATO) was administered p.o. in the dose of 0.30 mg/100g/day.

Controls received vehiculum. After two months of ATO administration blood pressure, serum triglycerides (TG) and total cholesterol (CHOL) were determined. Endothelial function of SMA was studied in vitro using evaluation of relaxant responses of precontracted SMA to acetylcholine. The serum TG of control male HTGs were found to be statistically higher than those of female controls, while CHOL and blood pressure did not share gender differences. Responses of SMA of female control HTGs were statistically decreased compared to their male counterparts. ATO treatment induced decrease in blood pressure and TG of both males and females, yet CHOL values were reduced only in females. The protective effect of ATO on SMA endothelial function was much more pronounced in females compared to males.

We conclude that vascular endothelial dysfunction of aged HTG rats is more severe and more attenuated by ATO in females compared to males. The protective effect of ATO on vascular endothelial function does not seem to depend solely on its lipid lowering action.
The effect of different bioregulators on lateral shoot formation in maiden apple trees
Authors: Gąstoł Maciej , Domagała-Świątkiewicz Iwona , Bijak Michał
Published: February 2013

One-year-old Malus domestica Borkh. ‘Boskoop’ and ‘Mutsu’ nursery trees on M.9 rootstock were treated with foliar sprays of different BA + GA3 mixtures (450 + 450 mg dm-3 or 780 + 120 mg dm-3) or BA + GA4+7 combinations (450 + 450 or 330 + 570 mg dm-3). Both cultivars showed strong apical dominance; however, increased branching potential was observed following the use of exogenous growth regulators. All of the investigated branching agents revealed a high effectiveness, yet only after one treatment. Environmental factors played a major role in the induction of sylleptic shoot formation, especially in the case of ‘Boskoop’. In the case of ‘Boskoop’, the branching effect was correlated with several vegetative growth properties (tree height, trunk diameter), while for ‘Mutsu’, a different branching pattern was found with no correlations ascertained. No tree injuries were observed following the use of a chemical branching agent.
Pain Treatment for Patients With Osteoarthritis and Central Sensitization
Authors: Lluch Girbés Enrique , Nijs Jo , Torres-Cueco Rafael , López Cubas Carlos
Published: February 2013

Osteoarthritis is one of the most frequent, disabling, and costly pathologies of modern society. Among the main aims of osteoarthritis management are pain control and functional ability improvement. The exact cause of osteoarthritis pain remains unclear. In addition to the pathological changes in articular structures, changes in central pain processing or central sensitization appear to be involved in osteoarthritis pain. The latter calls for a broader approach to the management of patients with osteoarthritis. Yet, the scientific literature offers scant information addressing the treatment of central sensitization, specifically in patients with osteoarthritis. Interventions such as cognitive-behavioral therapy and neuroscience education potentially target cognitive-emotional sensitization (and descending facilitation), and centrally acting drugs and exercise therapy can improve endogenous analgesia (descending inhibition) in patients with osteoarthritis. Future studies should assess these new treatment avenues.
Incidence of high-frequency hearing loss after microvascular decompression for hemifacial spasm
Authors: Ying Tingting , Thirumala Parthasarathy , Shah Aalap , Nikonow Tara , Wichman Kelley , Holmes Maura , Hirsch Barry , Chang Yuefang , Gardner Paul , Habeych Miguel , Crammond Donald J. , Burkhart Lois , Horowitz Michael , Balzer Jeffrey
Published: February 2013

Object

The primary aim of this study was to evaluate the incidence and discuss the pathogenesis of high-frequency hearing loss (HFHL) after microvascular decompression (MVD) for hemifacial spasm (HFS).

Methods

Preoperative and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from 94 patients who underwent MVD for HFS were analyzed. Pure tone audiometry at 0.25–2 kHz, 4 kHz, and 8 kHz was calculated for all individuals pre- and postoperatively ipsilateral and contralaterally. Intraoperative neurophysiological data were reviewed independently. An HFHL was defined as a change in pure tone audiometry of more than 10 dB at frequencies of 4 and 8 kHz.

Results

The incidence of HFHL was 50.00% and 25.53% ipsilateral and contralateral to the side of surgery, respectively. The incidence of HFHL adjusted for conductive and nonserviceable hearing loss was 26.6% ipsilaterally. The incidence of HFHL at 4 and 8 kHz on the ipsilateral side was 37.23% and 45.74%, respectively, and it was 10.64% and 25.53%, respectively, on the contralateral side. Maximal change in interpeak latency Waves I–V compared with baseline was the only variable significantly different between groups (p < 0.05). Sex, age, and side did not increase the risk of HFHL. Stepwise logistic regression analysis did not find any changes in intraoperative BAEPs to increase the risk of HFHL.

Conclusions

High-frequency hearing loss occurs in a significant number of patients following MVD surgery for HFS. Drill-induced noise and transient loss of CSF during surgery may impair hearing in the high-frequency ranges on both the ipsilateral and contralateral sides, with the ipsilateral side being more affected. Changes in intraoperative BAEPs during MVD for HFS were not useful in predicting HFHL. Follow-up studies and repeat audiological examinations may be helpful in evaluating the time course and prognosis of HFHL. Prospective studies focusing on decreasing intraoperative noise exposure, as well as auditory shielding devices, will establish causation and allow the team to intervene appropriately to decrease the risk of HFHL.
Stent-assisted embolization of 100 middle cerebral artery aneurysms
Authors: Johnson Andrew K. , Heiferman Daniel M. , Lopes Demetrius K.
Published: February 2013

Object

The introduction of intracranial stents to aneurysm treatment allows endovascular repair of nearly all aneurysms, but the safety and durability of stent-assisted embolization of middle cerebral artery (MCA) aneurysms is unclear.

Methods

Ninety-one patients with 100 complex MCA aneurysms not amenable to simple coiling were treated with stent-assisted embolization as a first option. Technical and clinical results, initial follow-up imaging, and long-term annual MR angiography (MRA) were reviewed.

Results

Intracranial stents were successfully deployed in all 100 aneurysms. There was 1 case of significant neurological morbidity (1%) and 1 case of death (1%) related to treatment. Initial posttreatment angiography revealed complete occlusion of 48 aneurysms (48%), a residual neck in 21 (21%), and residual aneurysm filling in 31 (31%). Follow-up imaging performed in 85 (90.4%) of a possible 94 aneurysms showed complete occlusion of 77 aneurysms (90.6%), residual neck in 3 (3.5%), and residual filling in 5 (5.9%). Four aneurysms (4.7%) required retreatment. Long-term MRA follow-up revealed stability or progressive thrombosis in 47 (97.9%) of 48 aneurysms. In 11 patients Y-configuration stenting caused only 1 minor complication and provided durable occlusion in all cases.

Conclusions

Stent-assisted techniques increase the number of aneurysms that may be treated endovascularly and represent an acceptable alternative to craniotomy. Stents provided adequate vessel reconstruction, low complication rates, and good long-term occlusion.
The Creation of the Concept through the Interaction of Philosophy with Science and Art
Authors: Schönher Mathias
Published: February 2013

In What Is Philosophy? we find philosophy devised as that power of thinking and creating which, in a division of labour with science and art, creates the concept. This division of labour points to the free interplay of Reason, Understanding and Imagination in Kant's Critique of Judgement and enables us to affirm, without obliterating the differences in kind, the non-hierarchical relationship between the three forms of thought that is asserted by Deleuze and Guattari. However, as powers of thinking and creating, philosophy, science and art do not inscribe themselves in a transcendental subject. Rather, Deleuze and Guattari conceive of them, following Spinoza's ‘creating nature’, as powers that express themselves in an attribute in which every thinking subject participates.
Is A New Life Possible? Deleuze and the Lines
Authors: Miranda Luis de
Published: February 2013

In his dialogues with Claire Parnet, Deleuze asserts that: ‘Whether we are individuals or groups, we are made of lines’ ( Deleuze and Parnet 2007 : 124). In A Thousand Plateaus (with Guattari), Deleuze calls these kinds of ‘lifelines’ or ‘lines of flesh’: break line (or segmental line, or molar line), crack line (or molecular line) and rupture line (also called line of flight) ( Deleuze and Guattari 2004a : 22). We will explain the difference between these three lines and how they are related to the ‘soul’. We will also explain how a singular individual or group can arise from the play of the lines. Eventually, we will introduce the concept of ‘Creal’ to develop the Deleuzian figure of the ‘Anomal’, the so(u)rcerer.
Pleistocene Palaeoart of Africa
Authors: Bednarik Robert
Published: February 2013

This comprehensive review of all currently known Pleistocene rock art of Africa shows that the majority of sites are located in the continent’s south, but that the petroglyphs at some of them are of exceptionally great antiquity. Much the same applies to portable palaeoart of Africa. The current record is clearly one of paucity of evidence, in contrast to some other continents. Nevertheless, an initial synthesis is attempted, and some preliminary comparisons with the other continents are attempted. Certain parallels with the existing record of southern Asia are defined.