bluuebunny/crossref_metadata_2025 huggingface dataset:
Extreme Grain-Based Cropping Systems: When Herbicide-Free Weed Management Meets Conservation Tillage in Northern Climates
Authors: Légère Anne , Shirtliffe Steven J. , Vanasse Anne , Gulden Robert H.
Published: March 2013

The challenges associated with the adoption of conservation tillage and/or low-input cropping systems, whether organic or herbicide-free, across Canada are shaped by scale, environment, and local practices. A study in eastern Canada captured the challenges of introducing low-input cropping systems in mature (20+ yr) tillage treatments in a barley/red clover/corn/soybean rotation. Each mature tillage system came with its own weed problems, but this did not affect crops such as barley and red clover, which produced similar yields across high and low input systems. However, some form of primary tillage was needed to achieve adequate weed control and yield in organic (ORG) and herbicide-free (HF) systems. The HF and ORG systems with no-till actually failed to produce a corn crop but produced soybean yields that were half or less than that for other treatments. The successful combination of conservation tillage practices and low-input systems in eastern Canada would thus appear to be crop-specific, being easier to achieve in competitive cereal crops. In western Canadian organic agriculture, tillage is practiced with low-disturbance chisel plows instead of inversion plows. However, green manure crops (summer cover crops) are often terminated with tandem discs. Both roller crimpers and mowing can successfully kill annual green manure crops such as field pea and rye, and usually result in reduced weed growth following termination. However, the lack of tillage can result in lower crop yields in wheat following green manure terminated by roller crimping compared to tillage. Challenges for no-till organic practices include perennial weed control and soil fertility. Overall, flexible crop production programs such as the former Manitoba Pesticide Free Production program and the “Agriculture raisonnéeTM” program in Québec are more likely to promote sustained environmental, economic, and social prosperity than rigid adherence to organic or no-till practices.
Evaluation of Cattle Grazing Distribution in Response to Weed and Legume Removal in Mixed Tall Fescue (Schedonorus phoenix) and Legume Pastures
Authors: Sather Bryan C. , Kallenbach Robert L. , Sexten William J. , Bradley Kevin W.
Published: March 2013

Grazing experiments were conducted during 2009 and 2010 to investigate the effect of herbicide application and subsequent weed removal on cattle grazing distribution in mixed tall fescue and legume pastures. At each location, herbicide applications were made to one-half of the grazed hectares to remove existing weeds and brush. Weeds and legumes were left nontreated across the remaining half of the grazed hectares at each location. Global positioning system tracking collars were fitted to three beef cows at each site and coordinates from each collar were recorded at 1-h intervals for 3 to 4 mo after herbicide application. At each location, broadleaf weeds were reduced from 1 to 51 kg ha−1, and legumes were completely eliminated in herbicide-treated compared to nontreated portions of the pastures. By the end of the season, the forage grass and legume component of pastures was greater and weed component lower in treated compared to nontreated portions of the pastures. By 3 mo after treatment, the cattle distribution was 1.3 to 5 times greater in herbicide-treated compared to nontreated portions of pastures. Overall, results from these experiments indicate herbicide treatment can increase desirable forage mass and thus modify cattle grazing distribution in pastures.
Overcoming Weed Management Challenges in Cover Crop–Based Organic Rotational No-Till Soybean Production in the Eastern United States
Authors: Mirsky Steven B. , Ryan Matthew R. , Teasdale John R. , Curran William S. , Reberg-Horton Chris S. , Spargo John T. , Wells M. Scott , Keene Clair L. , Moyer Jeff W.
Published: March 2013

Cover crop–based organic rotational no-till soybean production has attracted attention from farmers, researchers, and other agricultural professionals because of the ability of this new system to enhance soil conservation, reduce labor requirements, and decrease diesel fuel use compared to traditional organic production. This system is based on the use of cereal rye cover crops that are mechanically terminated with a roller-crimper to create in situ mulch that suppresses weeds and promotes soybean growth. In this paper, we report experiments that were conducted over the past decade in the eastern region of the United States on cover crop–based organic rotational no-till soybean production, and we outline current management strategies and future research needs. Our research has focused on maximizing cereal rye spring ground cover and biomass because of the crucial role this cover crop plays in weed suppression. Soil fertility and cereal rye sowing and termination timing affect biomass production, and these factors can be manipulated to achieve levels greater than 8,000 kg ha−1, a threshold identified for consistent suppression of annual weeds. Manipulating cereal rye seeding rate and seeding method also influences ground cover and weed suppression. In general, weed suppression is species-specific, with early emerging summer annual weeds (e.g., common ragweed), high weed seed bank densities (e.g. > 10,000 seeds m−2), and perennial weeds (e.g., yellow nutsedge) posing the greatest challenges. Due to the challenges with maximizing cereal rye weed suppression potential, we have also found high-residue cultivation to significantly improve weed control. In addition to cover crop and weed management, we have made progress with planting equipment and planting density for establishing soybean into a thick cover crop residue. Our current and future research will focus on integrated multitactic weed management, cultivar selection, insect pest suppression, and nitrogen management as part of a systems approach to advancing this new production system.
Weed Management in Mechanized-Sown, Zero-Till Dry-Seeded Rice
Authors: Chauhan Bhagirath S. , Abugho Seth B.
Published: March 2013

Weeds are the main constraint in the adoption of zero-till, dry-seeded rice systems because weeds and rice emerge simultaneously in these systems, and there is no standing water at crop establishment to suppress weeds. A study was conducted during the wet season of 2011 and the dry season of 2012 at the International Rice Research Institute to evaluate the performance of different herbicides in mechanized-sown, zero-till dry-seeded rice. Among the treatments evaluated, oxadiazon followed by penoxsulam + cyhalofop followed by one hand-weeding at 42 d after sowing, provided 23 to 35% higher yield than the nontreated control. The yields in the oxadiazon-treated plots were similar to those in the weed-free plots. Some weed species, including eclipta and doveweed, were not controlled by the evaluated herbicides. Therefore, there is a need to evaluate additional herbicides and to integrate them with cultural weed management strategies to manage such problematic weeds.
Differential Response of FourTrifoliumSpecies to Common Broadleaf Herbicides: Implications for Mixed Grass-Legume Swards
Authors: McCurdy James D. , McElroy J. Scott , Flessner Michael L.
Published: March 2013

Clovers are commonly included as utility plants within mixed grass swards, such as pastures and roadside right-of-ways. As such, they provide supplemental nitrogen, quality forage, and insect habitat. Yet weed control within mixed swards is often hampered by the lack of selective herbicides that are tolerated by clovers. Differential tolerance of legumes to common row-crop and pasture herbicides has previously been reported, yet little information is available that is specific to clover species. Herbicide injury of clover is often inconsistent, hypothetically due to differential species tolerance. Field and greenhouse experiments were conducted with the objective of testing differential tolerance amongst four clover species. Our experiments suggest varying tolerances amongst clover species and common broadleaf herbicides. Only imazaquin control differed due to species; however, treatment by clover interactions were further demonstrated due to variable reductions in clover height. Imazaquin, 2,4-D, 2,4-DB, and triclopyr height reductions differed due to clover species. Differential clover response to herbicide treatment should be an important consideration when managing mixed grass–clover swards and should be accounted for in future research. On a more practical level, our experiments demonstrate a range of herbicides that effectively control clover species, including atrazine, dicamba, clopyralid, 2,4-D, triclopyr, metsulfuron, and trifloxysulfuron. However, results suggest that 2,4-DB, imazethapyr, and bentazon are candidate herbicides for weed control in scenarios in which clover is a desirable crop.
Predicted Corn Yield Loss Due to Weed Competition Prior to Postemergence Herbicide Application on Wisconsin Farms
Authors: Fickett Nathanael D. , Boerboom Chris M. , Stoltenberg David E.
Published: March 2013

Approximately 50% of the genetically modified herbicide-resistant corn hectares in the United States are treated only with POST-applied herbicides for weed management. Although a high degree of efficacy can be obtained with POST-applied herbicides, delayed timing of application may result in substantial corn yield loss. Our goal was to characterize on-farm corn–weed communities prior to POST herbicide application and estimate potential corn-yield loss associated with early-season corn–weed competition. In 2008 and 2009, field surveys were conducted across 95 site-years in southern Wisconsin and recorded weed species, density, and height in addition to crop height, growth stage, and row spacing. WeedSOFT® was used to predict corn yield loss. Common lambsquarters, velvetleaf, dandelion, common ragweed, andAmaranthusspecies were the five most abundant broadleaf weed species across site-years, present in 92, 86, 59, 45, and 44% of all fields, respectively, at mean densities of 19, 3, 3, 4, and 3 plants m−2, respectively. Mean plant heights among these species were 17 cm or less. Grass and sedge species occurred in 96% of fields at a mean density of 25 plants m−2and height of 7 cm. The mean and median of total weed density across site-years were 96 and 52 plants m−2, with heights of 14 and 13 cm, respectively. Mean predicted corn yield loss was 4.5% with a mean economic loss of $62 ha−1. However, predicted yield loss was greater than 5% on one-third of the site-years, with a maximum of 26%. These results indicate that delayed application of POST herbicides has led to corn yield loss due to early-season weed-crop competition on a substantial number of fields across southern Wisconsin, and suggest that management tactics need to be improved to protect corn yield potential fully.
Influence of Herbicide Programs on Weed Management in Soybean with Resistance to Glufosinate and 2,4-D
Authors: Craigmyle Brett D. , Ellis Jeffrey M. , Bradley Kevin W.
Published: March 2013

A field experiment was conducted in Boone and Callaway counties in Missouri in 2010 and 2011 to investigate herbicide programs for the management of summer annual grass and broadleaf weeds in soybean resistant to 2,4-D and glufosinate. Results revealed that the addition of 0.56, 0.84, or 1.12 kg ha−1 2,4-D (amine) to either or both POST applications of glufosinate in a two-pass POST herbicide program increased control of common waterhemp compared to two POST applications of glufosinate alone. Similar levels of common cocklebur, giant foxtail, large crabgrass, and barnyardgrass control were achieved with any of the two-pass POST programs that contained 2,4-D compared to two-pass POST programs containing glufosinate alone. Similar control of these species was also achieved with the inclusion of 2,4-D in either the first or second pass of glufosinate. Two-pass programs resulted in the highest levels of weed control (90%). Annual grass and broadleaf weed control was as much as 59% lower when one-pass POST herbicide programs were compared to PRE followed by (fb) POST or two-pass POST programs. However, one-pass POST programs were sufficient to obtain exceptional control of common cocklebur and giant foxtail. Across all site years, soybean yields ranged from 2,680 to 3,100 kg ha−1 for all herbicide treatments, but did not differ statistically. Overall, results from these experiments indicate that compared to glufosinate alone, PRE fb POST or two-pass POST herbicide programs that incorporate 2,4-D amine with glufosinate in 2,4-D–resistant soybean enhance control of common waterhemp, while providing similar levels of control of other summer annual grass and broadleaf weeds.
The Effect of Cations and Ammonium Sulfate on the Efficacy of Dicamba and 2,4-D
Authors: Roskamp Jared M. , Chahal Gurinderbir S. , Johnson William G.
Published: March 2013

Dicamba or 2,4-D will be used POST for the control of weeds in soybean when dicamba- or 2,4-D-resistant soybean are commercialized. The active ingredients of both herbicides are weak acids in solution and may bind to cations present from hard water used as herbicide carrier or from foliar fertilizers added to spray solutions. The objectives of this research were (1) to determine if the efficacy of dicamba or 2,4-D are influenced by divalent cations, namely calcium (Ca), magnesium (Mg), manganese (Mn), and zinc (Zn), in the spray solution, and (2) to determine if adding ammonium sulfate (AMS) to the spray solution can overcome antagonism. The factorial study included five cation solutions (deionized water [dH2O], Ca at 590 mg L−1, Mg at 630 mg L−1, Mn at 4.97 L ha−1, and Zn at 2.33 L ha−1), two herbicide treatments (dicamba or 2,4-D), and two water conditioner treatments (without or with AMS at 20.37 g L−1). Treatments were applied to common lambsquarters, horseweed, and redroot pigweed. Control of horseweed and redroot pigweed increased when AMS was added to the 2,4-D treatments, irrespective of cation solution. Control of common lambsquarters was increased when AMS was added to 2,4-D for only the Ca and Mn cation solution. In contrast to the results obtained with 2,4-D, control of horseweed with dicamba was not influenced by cation solution. Tank-mixing AMS with dicamba increased control of both redroot pigweed and common lambsquarters in the dH2O, Mg, and Mn solutions.
Recent Weed Control, Weed Management, and Integrated Weed Management
Authors: Harker K. Neil , O'Donovan John T.
Published: March 2013

Integrated weed management (IWM) can be defined as a holistic approach to weed management that integrates different methods of weed control to provide the crop with an advantage over weeds. It is practiced globally at varying levels of adoption from farm to farm. IWM has the potential to restrict weed populations to manageable levels, reduce the environmental impact of individual weed management practices, increase cropping system sustainability, and reduce selection pressure for weed resistance to herbicides. There is some debate as to whether simple herbicidal weed control programs have now shifted to more diverse IWM cropping systems. Given the rapid evolution and spread of herbicide-resistant weeds and their negative consequences, one might predict that IWM research would currently be a prominent activity among weed scientists. Here we examine the level of research activity dedicated to weed control techniques and the assemblage of IWM techniques in cropping systems as evidenced by scientific paper publications from 1995 to June 1, 2012. Authors from the United States have published more weed and IWM-related articles than authors from any other country. When IWM articles were weighted as a proportion of country population, arable land, or crop production, authors from Switzerland, the Netherlands, New Zealand, Australia, and Canada were most prominent. Considerable evidence exists that research on nonherbicidal weed management strategies as well as strategies that integrate other weed management systems with herbicide use has increased. However, articles published on chemical control still eclipse any other weed management method. The latter emphasis continues to retard the development of weed science as a balanced discipline.
Bermudagrass (Cynodon dactylon) Control with Topramezone and Triclopyr
Authors: Brosnan James T. , Breeden Gregory K.
Published: March 2013

Common bermudagrass is a problematic weed within tall fescue turfgrass. Field research was conducted from 2010 to 2012 in Knoxville, TN, evaluating the efficacy of sequential applications of topramezone (12.5 and 25 g ha−1), triclopyr (1,120 g ha−1), and mixtures of topramezone + triclopyr for bermudagrass control in tall fescue turf. Sequential applications of fenoxaprop + triclopyr (100 + 1,120 g ha−1) were included for comparison. Three applications of each treatment were applied at 21-d intervals during July, August, and September of 2010 and 2011. Plots were stripped to receive tall fescue interseeding at 0 or 490 kg ha−1during September 2010 and 2011. Bermudagrass control with topramezone + triclopyr mixtures was greater than topramezone or triclopyr applied alone 14 wk after initial treatment (WAIT) each year. In the second year of this study, topramezone + triclopyr mixtures controlled bermudagrass 27 to 50% compared to 27% for fenoxaprop + triclopyr by 52 WAIT. However, bermudagrass control with topramezone + triclopyr mixtures increased to 88 to 92% by 52 WAIT when accompanied with tall fescue interseeding at 490 kg ha−1. Future research should evaluate effects of interseeding on the efficacy of different herbicides for weed control in cool- and warm-season turf.
Towards a No-Till No-Spray Future? Introduction to a Symposium on Nonchemical Weed Management for Reduced-Tillage Cropping Systems
Authors: Brainard Daniel C. , Haramoto Erin , Williams Martin M. , Mirsky Steven
Published: March 2013

Reduced-tillage systems including no-tillage and striptillage have well-known benefits for conserving and improving soils, protecting vulnerable crops from extreme weather events, and reducing labor and fuel costs associated with full-width inversion tillage (Franzluebbers 2002, 2005; Parsch et al. 2001; Pesant et al. 1987; Spargo et al. 2008). Despite these benefits, reduced-tillage has not been widely adopted in many cropping systems due in part to the increased difficulty of managing weeds when tillage is not used. Not surprisingly, adoption of reduced-tillage has occurred primarily in crops for which low-cost, effective herbicides are available, including glyphosate-resistant soybean [Glycine max (L.) Merr.], corn (Zea mays L.), cotton (Gossypium hirsutum L.), and sugarbeets (Beta vulgaris L.) (Horowitz et al. 2010; Tarkalson et al. 2012). Increased use of a narrow range of herbicides in these cropping systems has exacerbated problems of herbicide resistance (Duke and Powles 2009; Heap 2012). Conversely, adoption of reduced-tillage has been limited in crops where effective herbicides are not available (e.g. in “minor crops” like vegetables) or prohibited (e.g. in organic production systems). Research aimed at identifying nonchemical approaches to managing weeds in reduced-tillage production systems has the potential to increase adoption of reducedtillage while minimizing herbicide use and selection pressure for herbicide resistance in production systems currently using reduced tillage (Figure 1).
Scaling of fracture and acoustic emission in concrete
Authors: Invernizzi Stefano , Lacidogna Giuseppe , Carpinteri Alberto
Published: March 2013

A combined compression and acoustic emission (AE) test is proposed to study the scaling of fracture and AE in concrete-like specimens with different size and slenderness. The cylindrical concrete specimens were drilled from two pilasters sustaining an Italian viaduct built in the 1950s. A finite-element method model of the pure compression tests is presented, which is able to describe both the discrete cracking at the matrix–aggregate interface and the smeared cracking of the matrix. The adopted mesoscale modelling directly accounts for the aggregate dimensional distribution, each aggregate being explicitly represented. In this way, the crack patterns can be simulated correctly, as well as the load–displacement curve. During microcrack propagation, AE events can be clearly detected experimentally. Therefore, the number of AE can be put into relation with the number of Gauss points in the finite-element model where cracking takes place. A good correlation is found between the amount of cracking simulated numerically and the experimental AE counting number for different specimen sizes, and the two quantities show the same scaling exponent. This evidence reconfirms the assumption, provided by fragmentation theories, that the energy dissipation during microcrack propagation occurs in a fractal domain.
Enhancing conservation of large‐river biodiversity by accounting for tributaries
Authors: Pracheil Brenda M , McIntyre Peter B , Lyons John D
Published: March 2013

Alteration of rivers for human use has resulted in substantial biodiversity declines, particularly for species restricted to the largest rivers. Conservation and restoration efforts on large rivers often focus on the mainstem, but societal reliance on benefits derived from these alterations generally prevents complete restoration of the river. We propose that certain tributaries, by virtue of their lower degree of alteration, offer underappreciated opportunities for conserving large‐river biota. Using the distribution patterns of large‐river specialist fishes from the Mississippi River Basin, we identify a threshold discharge (166 cubic meters per second) beyond which tributaries support all or most of these species. We merge our macroecological analysis of assemblage structure with data on dam locations to identify tributaries where restoration efforts offer the highest potential conservation gains for 60 of the 68 large‐river specialist fish species that are of state, federal, or international conservation concern. Given the highly altered state of many mainstem rivers, this analytical approach could be used to select tributaries that will aid in the conservation of large‐river species worldwide.
Correlation from Undiluted Vitreous Cytokines of Untreated Central Retinal Vein Occlusion with Spectral Domain Optical Coherence Tomography
Authors: Koss MJ , Pfister M , Rothweiler F , Rejdak R , Ribeiro R , Cinatl J , Schubert R , Kohnen T , Koch FH
Published: March 2013

Purpose:

To correlate inflammatory and proangiogenic key cytokines from undiluted vitreous of treatment-naïve central retinal vein occlusion (CRVO) patients with SD-OCT parameters.

Methods:

Thirty-five patients (age 71.1 years, 24 phakic, 30 nonischemic) underwent intravitreal combination therapy, including a single-site 23-gauge core vitrectomy. Twenty-eight samples from patients with idiopathic, non-uveitis floaterectomy served as controls. Interleukin 6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and vascular endothelial growth factor (VEGF-A) levels were correlated with the visual acuity (logMar), category of CRVO (ischemic or nonischemic) and morphologic parameters, such as central macular thickness-CMT, thickness of neurosensory retina-TNeuro, extent of serous retinal detachment-SRT and disintegrity of the IS/OS and others.

Results:

The mean IL-6 was 64.7pg/ml (SD ± 115.8), MCP-1 1015.7 ( ± 970.1), and VEGF-A 278.4 ( ± 512.8), which was significantly higher than the control IL-6 6.2 ± 3.4pg/ml (P=0.06), MCP-1 253.2 ± 73.5 (P<0.0000001) and VEGF-A 7.0 ± 4.9 (P<0.0006). All cytokines correlated highly with one another (correlation coefficient r=0.82 for IL-6 and MCP-1; r=0.68 for Il-6 and VEGF-A; r=0.64 for MCP-1 and VEGF-A). IL-6 correlated significantly with CMT, TRT, SRT, dIS/OS, and dELM. MCP-1 correlated significantly with SRT, dIS/OS, and dELM. VEGF-A correlated not with changes in SD-OCT, while it had a trend to be higher in the ischemic versus the nonischemic CRVO group (P=0.09).

Conclusions:

The inflammatory cytokines were more often correlated with morphologic changes assessed by SD-OCT, whereas VEGF-A did not correlate with CRVO-associated changes in SD-OCT. VEGF inhibition alone may not be sufficient in decreasing the inflammatory response in CRVO therapy.
Soft tissue changes after mandibular setback and bimaxillary surgery in Class III patients
Authors: Jokić Davor , Jokić Dražen , Uglešić Vedran , Macan Darko , Knežević Predrag
Published: March 2013

Objective:

To evaluate the relationship between soft tissue and bone structure for Class III patients before and after bilateral sagittal split osteotomy (BSSO) and bimaxillary orthognathic surgery; to determine the impact of other factors on soft tissue change; and to evaluate correlations between thickness of tissue before surgery, SNA, SNB, and ANB angles, and soft tissue changes.

Materials and Methods:

The study included 78 Class III patients treated only with BSSO or with BSSO and Le Fort I osteotomy. Lateral cephalograms were taken before and 3 months to 1 year after surgery. After all points of the Zagreb82 and Legan and Burstone profile analysis were traced, the ratio of five soft tissue points before and after surgery was evaluated.

Results:

Soft tissue between points Sn and A and upper lip showed statistically significant changes for patients treated with bimaxillary surgery and BSSO. Only gender had an influence on soft tissue change. The correlation between soft tissue thickness and changes after surgery was significant. A change in SNB angle correlated with upper lip thickness for patients treated with BSSO but not for patients treated with BSSO and Le Fort I. SNA angle changes correlated with soft tissue changes between points Sn and A.

Conclusion:

Results of this study show soft tissue changes after BSSO and BSSO and Le Fort I and eliminate the deficiencies that were indicated in the meta-analysis of soft tissue changes from a previous study.
Eigenvalue results for pseudomonotone perturbations of maximal monotone operators
Authors: Kim In-Sook , Bae Jung-Hyun
Published: March 2013

Let X be an infinite-dimensional real reflexive Banach space such that X and its dual X* are locally uniformly convex. Suppose that T: X⊃D(T) → 2X* is a maximal monotone multi-valued operator and C: X⊃D(C) → X* is a generalized pseudomonotone quasibounded operator with L ⊂ D(C), where L is a dense subspace of X. Applying a recent degree theory of Kartsatos and Skrypnik, we establish the existence of an eigensolution to the nonlinear inclusion 0 ∈ T
x + λ
C
x, with a regularization method by means of the duality operator. Moreover, possible branches of eigensolutions to the above inclusion are discussed. Furthermore, we give a surjectivity result about the operator λT + C when λ is not an eigenvalue for the pair (T, C), T being single-valued and densely defined.
Exponential generating function of hyperharmonic numbers indexed by arithmetic progressions
Authors: Mező István
Published: March 2013

There is a circle of problems concerning the exponential generating function of harmonic numbers. The main results come from Cvijovic, Dattoli, Gosper and Srivastava. In this paper, we extend some of them. Namely, we give the exponential generating function of hyperharmonic numbers indexed by arithmetic progressions; in the sum several combinatorial numbers (like Stirling and Bell numbers) and the hypergeometric function appear.
Approximate multiplication in adaptive wavelet methods
Authors: Černá Dana , Finěk Václav
Published: March 2013

Cohen, Dahmen and DeVore designed in [Adaptive wavelet methods for elliptic operator equations: convergence rates, Math. Comp., 2001, 70(233), 27–75] and [Adaptive wavelet methods II¶beyond the elliptic case, Found. Comput. Math., 2002, 2(3), 203–245] a general concept for solving operator equations. Its essential steps are: transformation of the variational formulation into the well-conditioned infinite-dimensional l
2-problem, finding the convergent iteration process for the l
2-problem and finally using its finite dimensional approximation which works with an inexact right-hand side and approximate matrix-vector multiplication. In our contribution, we pay attention to approximate matrix-vector multiplication which is enabled by an off-diagonal decay of entries of the wavelet stiffness matrices. We propose a more efficient technique which better utilizes actual decay of matrix and vector entries and we also prove that this multiplication algorithm is asymptotically optimal in the sense that storage and number of floating point operations, needed to resolve the problem with desired accuracy, remain proportional to the problem size when the resolution of the discretization is refined.
Self-assembly of aniline oligomers and their induced polyaniline supra-molecular structures
Authors: Feng Jing , Jing Xinli , Li Yu
Published: March 2013

Aniline chemical oxidative polymerisation (COP), which produces various polyaniline (PANI) and oligoaniline supra-molecular structures, can be regarded as an in situ self-assembly process. This review provides a brief introduction to recent work on the structural characters and self-assembly behaviours of oligomeric aniline chemical oxidation products; it is focused on the relationships between the oligomeric species and morphology of the final products such as PANI nanoparticles, nanofibres/rods, nanotubes or oligoaniline nanosheets, micro/nanospheres in aniline COP systems. Several mechanisms proposed as explanations for the formation of typical supra-molecular structures are discussed in order to illustrate the roles of aniline oligomers. This article concludes with our perspectives on future work remaining to be done to uncover the formation mechanism of supra-molecular structures constructed by aniline chemical oxidation products and their controllable synthesis.
Translation, Cross-cultural Adaptation, and Clinimetric Testing of Instruments Used to Assess Patients With Patellofemoral Pain Syndrome in the Brazilian Population
Authors: Da Cunha Ronaldo Alves , Costa Leonardo Oliveira Pena , Hespanhol Luiz Carlos , Pires Raquel Simoni , Kujala Urho M. , Lopes Alexandre Dias
Published: March 2013

Study Design

Clinical measurement study.

Objectives

To cross-culturally adapt the Anterior Knee Pain Scale (AKPS), the Functional Index Questionnaire (FIQ), and the Pain Severity Scale (PSS) for patellofemoral pain syndrome (PFPS) into Brazilian Portuguese. This study also aimed to test the measurement properties of the AKPS, the FIQ, and the PSS, and the existing Brazilian Portuguese versions of the numeric pain rating scale (NPRS) and the Global Perceived Effect scale in a group with PFPS.

Background

PFPS is a common condition. Therefore, translated, culturally adapted, and clinimetrically tested instruments for measuring PFPS are needed.

Methods

The AKPS, FIQ, and PSS instruments were cross-culturally adapted into Brazilian Portuguese. The measurement properties of the AKPS, FIQ, PSS, NPRS, and Global Perceived Effect scale (internal consistency, ceiling and floor effects, and construct validity) were tested in 83 patients with PFPS. The reproducibility and responsiveness were tested in 52 patients with PFPS in a test-retest design, with follow-up testing at 48 to 72 hours and at 4 weeks after baseline.

Results

The AKPS, the FIQ, and the PSS yielded adequate internal consistency (Cronbach alpha ranging from .75 to .87) and excellent reliability (intraclass correlation coefficients [model 2,1] ranging from 0.90 to 0.97). The AKPS and the PSS yielded very good agreement (standard error of measurement, 2.9% and 3.5%, respectively). The highest correlations were observed among the AKPS, the FIQ, and the PSS (Pearson r>0.60, P<.05). No floor or ceiling effects were observed for any of the instruments. Effect sizes used for measuring internal responsiveness ranged from moderate to high for all measures. The NPRS and the AKPS were the measures with the highest external responsiveness.

Conclusion

The Brazilian Portuguese versions of the AKPS, FIQ, PSS, NPRS, and global Perceived Effect scale have acceptable measurement properties. J Orthop Sports Phys Ther 2013;43(5):332–339. Epub 13 March 2013. doi:10.2519/jospt.2013.4228
Efficacy of Thrust and Nonthrust Manipulation and Exercise With or Without the Addition of Myofascial Therapy for the Management of Acute Inversion Ankle Sprain: A Randomized Clinical Trial
Authors: Truyols-Domínguez Sebastián , Salom-Moreno Jaime , Abian-Vicen Javier , Cleland Joshua A. , Fernández-De-Las-Peñas César
Published: March 2013

Study Design

Randomized clinical trial.

Objective

To compare the effects of thrust and nonthrust manipulation and exercises with and without the addition of myofascial therapy for the treatment of acute inversion ankle sprain.

Background

Studies have reported that thrust and nonthrust manipulations of the ankle joint are effective for the management of patients post-ankle sprain. However, it is not known whether the inclusion of soft tissue myofascial therapy could further improve clinical and functional outcomes.

Methods

Fifty patients (37 men and 13 women; mean ± SD age, 33 ± 10 years) post-acute inversion ankle sprain were randomly assigned to 2 groups: a comparison group that received a thrust and nonthrust manipulation and exercise intervention, and an experimental group that received the same protocol and myofascial therapy. The primary outcomes were ankle pain at rest and functional ability. Additionally, ankle mobility and pressure pain threshold over the ankle were assessed by a clinician who was blinded to the treatment allocation. Outcomes of interest were captured at baseline, immediately after the treatment period, and at a 1-month follow-up. The primary analysis was the group-by-time interaction.

Results

The 2-by-3 mixed-model analyses of variance revealed a significant group-by-time interaction for ankle pain (P<.001) and functional score (P = .002), with the patients who received the combination of nonthrust and thrust manipulation and myofascial intervention experiencing a greater improvement in pain and function than those who received the nonthrust and thrust manipulation intervention alone. Significant group-by-time interactions were also observed for ankle mobility (P<.001) and pressure pain thresholds (all, P<.01), with those in the experimental group experiencing greater increases in ankle mobility and pressure pain thresholds. Between-group effect sizes were large (d>0.85) for all outcomes.

Conclusion

This study provides evidence that, in the treatment of individuals post-inversion ankle sprain, the addition of myofascial therapy to a plan of care consisting of thrust and nonthrust manipulation and exercise may further improve outcomes compared to a plan of care solely consisting of thrust and nonthrust manipulation and exercise. However, though statistically significant, the difference in improvement in the primary outcome between groups was not greater than what would be considered a minimal clinically important difference. Future studies should examine the long-term effects of these interventions in this population.

Level of Evidence

Therapy, level 1b-. J Orthop Sports Phys Ther 2013;43(5):300–309. Epub 13 March 2013. doi:10.2519/jospt.2013.4467
Using Functional Magnetic Resonance Imaging to Determine if Cerebral Hemodynamic Responses to Pain Change Following Thoracic Spine Thrust Manipulation in Healthy Individuals
Authors: Sparks Cheryl , Cleland Joshua A. , Elliott James M. , Zagardo Michael , Liu Wen-Ching
Published: March 2013

Study Design

Case series.

Objectives

To use blood oxygenation level-dependent functional magnetic resonance imaging (fMRI) to determine if supraspinal activation in response to noxious mechanical stimuli varies pre-and post-thrust manipulation to the thoracic spine.

Background

Recent studies have demonstrated the effectiveness of thoracic thrust manipulation in reducing pain and improving function in some individuals with neck and shoulder pain. However, the mechanisms by which manipulation exerts such effects remain largely unexplained. The use of fMRI in the animal model has revealed a decrease in cortical activity in response to noxious stimuli following manual joint mobilization. Supraspinal mediation contributing to hypoalgesia in humans may be triggered following spinal manipulation.

Methods

Ten healthy volunteers (5 women, 5 men) between the ages of 23 and 48 years (mean, 31.2 years) were recruited. Subjects underwent fMRI scanning while receiving noxious stimuli applied to the cuticle of the index finger at a rate of 1 Hz for periods of 15 seconds, alternating with periods of 15 seconds without stimuli, for a total duration of 5 minutes. Subjects then received a supine thrust manipulation directed to the mid-thoracic spine and were immediately returned to the scanner for reimaging with a second delivery of noxious stimuli. An 11-point numeric pain rating scale was administered immediately after the application of noxious stimuli, premanipulation and postmanipulation. Blood oxygenation level-dependent fMRI recorded the cerebral hemodynamic response to the painful stimuli premanipulation and postmanipulation.

Results

The data indicated a significant reduction in subjects' perception of pain (P<.01), as well as a reduction in cerebral blood flow as measured by the blood oxygenation level-dependent response following manipulation to areas associated with the pain matrix (P<.05). There was a significant relationship between reduced activation in the insular cortex and decreased subjective pain ratings on the numeric pain rating scale (r = 0.59, P<.05).

Conclusion

This study provides preliminary evidence that suggests that supraspinal mechanisms may be associated with thoracic thrust manipulation and hypoalgesia. However, because the study lacked a control group, the results do not allow for the discernment of the causative effects of manipulation, which may also be related to changes in levels of subjects' fear, anxiety, or expectation of successful outcomes with manipulation. Future investigations should strive to elicit more conclusive findings in the form of randomized clinical trials. J Orthop Sports Phys Ther 2013;43(5):340–348. Epub 13 March 2013. doi:10.2519/jospt.2013.4631
Tracing the depth of the Holocene ice in North Greenland from radio-echo sounding data
Authors: Karlsson Nanna B. , Dahl-Jensen Dorthe , Prasad Gogineni S. , Paden John D.
Published: March 2013

Radio-echo sounding surveys over the Greenland ice sheet show clear, extensive internal layering, and comparisons with age–depth scales from deep ice cores allow for dating of the layering along the ice divide. We present one of the first attempts to extend the dated layers beyond the ice core drill sites by locating the depth of the Bølling–Allerød transition in >400 flight-lines using an automated fitting method. Results show that the transition is located in the upper one-third of the ice column in the central part of North Greenland, while the transition lowers towards the margin. This pattern mirrors the present surface accumulation, and also indicates that a substantial amount of pre-Holocene ice must be present in central North Greenland.
Subglacial bathymetry and sediment layer distribution beneath the Pine Island Glacier ice shelf, West Antarctica, modeled using aerogravity and autonomous underwater vehicle data
Authors: Muto Atsuhiro , Anandakrishnan Sridhar , Alley Richard B.
Published: March 2013

Pine Island Glacier (PIG), West Antarctica, has been experiencing acceleration in its flow speed and mass loss for nearly two decades, driven in part by an increase in the delivery of relatively warm Circumpolar Deep Water (CDW). However, at present, the configuration of the sub-ice-shelf cavity and bed conditions beneath the PIG ice shelf that dictate such oceanic influences remain poorly understood. Here, we use aerogravity data and ocean bottom depths measured by an autonomous underwater vehicle (AUV) to model the bathymetry and sediment layer thickness beneath the PIG ice shelf. Results reveal that the deep basins, previously found by AUV on both landward and seaward sides of a submarine ridge, extend substantially to the north and south. The water column thickness of the basins reaches 400-550 m on the landward side of the ridge and 500-600 m on the seaward side. The sediment layer covers the whole expanse of the seabed beneath the ice shelf, and the thickness is in the range ∼200-1000 m. The thinnest sediments (<200 m) are found on the seaward slope of the submarine ridge, suggesting that erosion by advancing ice may have been concentrated in the lee of the topographic high.
A blue-ice ecosystem on the margins of the East Antarctic ice sheet
Authors: Hodson Andy , Paterson Harriet , Westwood Karen , Cameron Karen , Laybourn-Parry Johanna
Published: March 2013

Freezing temperatures, desiccation and high levels of solar radiation make the surface of the Antarctic ice sheet one of Earth’s harshest habitats. However, our study in the Vestfold Hills area of East Antarctica shows that favourable conditions for microbial production become established just beneath the surface of blue-ice areas, which collectively cover about 2% of the ice-sheet periphery. Their translucent, wind-polished surface allows solar heating to create meltwater in a greenhouse-type environment at depths of up to 1 m. Melting is intensified around dark debris particles, or cryoconite, where we found microbiological activity to be greatest. Rates of photosynthesis (average 2060 ng C (g cryoconite)−1d−1) were adapted to low light intensities (∼10% of surface irradiance values) and most likely dominated by cyanobacteria and Chloroplastida. A heterotrophic bacterial community was also found to be active within the cryoconite, although average bacterial growth rates (5.7 ng C (g cryoconite)−1d−1) were far lower than average community respiration (1870 ng C (g cryoconite)−1d−1). The majority of the respired carbon was most likely associated with the autotrophs and several protists. Therefore, blue-ice areas constitute oases for microbial life around the periphery of Earth’s coldest ice sheet.
X-ray microtomography analysis of isothermal densification of new snow under external mechanical stress
Authors: Schleef Stefan , Löwe Henning
Published: March 2013

We have investigated the isothermal densification of new snow under an external mechanical stress. New snow samples that mimic natural snow were made in the laboratory by sieving ice crystals grown in a snowmaker. This allowed us to assemble homogeneous initial samples with reproducible values of low density and high specific surface area (SSA). Laboratory creep experiments were conducted in an X-ray microtomograph at −20°C for 2 days. We focused on the evolution of density and SSA as a function of constant stress at a single temperature. External mechanical stresses resembled natural overburden stresses of a snow sample at depths of ∼0–30 cm of new snow. We demonstrate that densification increases with higher external stress and lower initial densities. We find that the evolution of the SSA is independent of the density and follows a unique decay for all measurements of the present type of new snow. The results suggest that details of the SSA decrease can be investigated using carefully designed experiments of short duration which are convenient to conduct. Additionally, we calculated the strain evolution and identify transient creep behavior that does not follow the Andrade creep law of denser snow or polycrystalline ice.
Incidence of Bacteremia After Endoscopic Variceal Ligation of Oesophageal Varices in Cirrhotic Patients
Authors: Alam Md Shahinul , Lama Thupten K , Alam AKM Khorshed
Published: March 2013

Bacteremia and infectious sequelea are frequent  complications after sclerotherapy. As cirrhotic patients are  immune deficient, bacteremia occurring as a consequence  of endoscopic variceal ligation (EVL) may develop systemic  infection. The aim of the study was to see the incidence of  bacteremia in cirrhotic patients after EVL.  In this study 91 cirrhotic patients with grade II-III  oesophageal varices were enrolled and 100 EVL sessions  were done. Patients receiving antibiotics, having evidence  of infection were excluded. After the completion of EVL,  blood samples for culture and sensitivity were collected at  5minute and after 30minute and subculture done in Blood  Agar and MacConkey Agar media. We followed the patients  for a week.  Of the one hundred cases there were 30 subjects in Child A,  48 in Child B and 13 in Child C class. Four patients (4%)  had positive blood culture after EVL, three of Child A class  and one of Child B class and non in Child C class. All three  patients of Child A had culture positive in their 30minute  sample and not in 5 minute sample. The Child B patient had  culture positive in his 5minute sample and not in 30minute  sample. The bacterium isolated was Coagulase negative  Staphylococcus, which we considered it as contaminant.  None of these patients developed any infectious sequelea.  The incidence of bacteremia after EVL is yet to be  ascertained. Post EVL antibiotic prophylaxis is not  recommended. DOI: http://dx.doi.org/10.3329/medtoday.v24i1.14109 Medicine TODAY Vol.24(1) 2012 pp.20-22
Short Term Outcome of Urethroplasty with or without Urethral Stent: A Comparative Study
Authors: Karim SM Rezaul , Abdullah Sheikh Md , Shaha Bablu Kumar , Rahman Md Matiur , Amin Md Ruhul
Published: March 2013

Urethroplasty is the surgery for Hypospadias. The most  common complication of Hypospadias surgery is  urethro-cutaneous (U-C) fistula. We designed this study to  compare the short term outcome of Urethroplasty with or  without urethral stent postoperatively. A total 30 patients of  distal penile hypospadias except glnular variety have been  studied prospectively in Pediatric Surgery Department of  Banga Bandhu Sheikh Mujib Medical University, Dhaka for a  period of 20 months, from March 2005 to October 2006. All  patients were divided into Group-A (pt with stent) and Group-  B (pts without stent). Age ranges of all patients were 2-12  years. After operation no patient developed urinary retention  in stented group (Group-A) and 3 patients developed urinary  retention which was managed by suprapubic puncture. 5  patients developed urethra-cutaneous fistula in stented group  (Group- A) and 2 patients developed fistula in non stented  group (Group-B). Calibration was done in all patients after 2  weeks of operation. Before calibration 2 patients came to us  with narrow urinary stream of Group-B. After analyzing the  result, it was concluded that the short term outcome of  Urethroplasty without postoperative urethral stent is better  than with stent specially in terms of Urethro-cutaneous fistula. DOI: http://dx.doi.org/10.3329/medtoday.v24i1.14110 Medicine TODAY Vol.24(1) 2012 pp.23-26
Managing by measuring
Authors: Nylander Erik , Aman Robert , Hallqvist Anders , Malmquist Anna , Sandberg Fredrik
Published: March 2013

No abstract available.