bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Primary Osteocyte Differentiation in a 3D Culture System
Authors: Boukhechba Florian , Balaguer Thierry , Michiels Jean-François , Ackermann Karin , Quincey Danielle , Bouler Jean-Michel , Pyerin Walter , Carle Georges F. , Rochet Nathalie
Published: May 2009

Studies on primary osteocytes, which compose >90–95% of bone cells, embedded throughout the mineralized matrix, are a major challenge because of their difficult accessibility and the very rare models available in vitro. We engineered a 3D culture method of primary human osteoblast differentiation into osteocytes. These 3D-differentiated osteocytes were compared with 2D-cultured cells and with human microdissected cortical osteocytes obtained from bone cryosections. Human primary osteoblasts were seeded either within the interspace of calibrated biphasic calcium phosphate particles or on plastic culture dishes and cultured for 4 wk in the absence of differentiation factors. Osteocyte differentiation was assessed by histological and immunohistological analysis after paraffin embedding of culture after various times, as well as by quantitative RT-PCR analysis of a panel of osteoblast and osteocyte markers after nucleic acid extraction. Histological analysis showed, after only 1 wk, the presence of an osteoid matrix including many lacunae in which the cells were individually embedded, exhibiting characteristics of osteocyte-like cells. Real-time PCR expression of a set of bone-related genes confirmed their osteocyte phenotype. Comparison with plastic-cultured cells and mature osteocytes microdissected from human cortical bone allowed to assess their maturation stage as osteoid-osteocytes. This model of primary osteocyte differentiation is a new tool to gain insights into the biology of osteocytes. It should be a suitable method to study the osteoblast-osteocyte differentiation pathway, the osteocyte interaction with the other bone cells, and orchestration of bone remodeling transmitted by mechanical loading and shear stress. It should be used in important cancer research areas such as the cross-talk of osteocytes with tumor cells in bone metastasis, because it has been recently shown that gene expression in osteocytes is strongly affected by cancer cells of different origin. It could also be a very efficient tool for drug testing and bone tissue engineering applications.
Retrieval Analysis of Total Disc Replacements: Implications for Standardized Wear Testing
Authors: Kurtz S , Siskey R , Ciccarelli L , van Ooij A , Peloza J , Villarrage M
Published: May 2009

The purpose of this study was to evaluate the wear and surface damage mechanisms of polyethylene in retrieved CHARITÉ total disc replacements. The retrieved implants showed evidence of adhesive/abrasive wear mechanisms in the central domed region of the implants. In addition, there was also evidence of macroscopic rim damage, including radial cracking, plastic deformation, and third body damage. The retrieved total disc replacements (TDRs) displayed surface damage observed previously in both hip and knee replacements. The information from this study will be useful for engineers seeking to adequately replicate long-term, clinically relevant damage modes of TDRs using in vitro testing methods.
Application of the Normalization Method to Dynamic Fracture Toughness Testing of Alloy 718
Authors: Graham SM
Published: May 2009

The fracture toughness and tensile properties of Alloy 718 were measured at quasi-static and dynamic loading rates for two different heat treatments and two product forms. Two different methods for conducting the dynamic tests were investigated; one involving interrupted tests and the other utilizing a single impact. The interrupted test method used multiple impacts with displacement limits to enable measurement of crack lengths at intermediate points. The normalization method was used to generate tearing resistance curves for the dynamic tests following the guidelines in ASTM Standard Test Method for measurement of Fracture Toughness (E 1820). The analysis pointed out the importance of obtaining a good measurement of load, displacement, and crack length at the point of maximum displacement (the anchor point). As the amount of ductile crack extension increased, the uncertainty in the plasticity function fit also increased. Methods to improve the fit were investigated, including the addition of anchor points from multiple tests, and use of a tangency point to estimate initiation. The resulting curves are compared to ascertain the variability obtained from nominally identical specimens, and to evaluate the effect of loading rate on the plasticity function. The normalization tearing resistance curves are compared with curves generated from the interrupted tests using compliance measurements during unloads to determine crack extension. Good agreement was obtained between the two methods of measuring tearing resistance, thereby validating the normalization analysis. The tests showed that multiple impacts drive down the tearing resistance, which may be significant in applications where a dynamic event causes load fluctuation.
Use of CPXSD for Generation of Effective Fast Multigroup Libraries for Pressure Vessel Fluence Calculations
Authors: Alpan F. Arzu , Haghighat Alireza
Published: May 2009

Multigroup (i.e., broad-group) libraries play a significant role in the accuracy of transport calculations. There are several broad-group libraries available for particular applications. For example the 47-neutron (26 fast groups), 20-gamma-group BUGLE libraries are commonly used for light water reactor shielding and pressure vessel dosimetry problems. However, there is no publicly available methodology to construct group structures for a problem and objective of interest. Therefore, we have developed the Contributon and Point-wise Cross-Section Driven (CPXSD) methodology, which constructs effective fine- and broad-group structures. In this paper, we use the CPXSD methodology to construct broad-group structures for fast neutron dosimetry problems. It is demonstrated that the broad-group libraries generated from CPXSD constructed group structures, while only 14 groups (rather than 26 groups) in the fast energy range are in good agreement (∼1 %–2 %) with the fine-group library from which they were derived, in reaction rate calculations.
Digital Multiparameter System for Characterizing the Neutron-Gamma Field in the LR-O Experimental Reactor
Authors: Bureš Z. , Cvachovec F. , Čeleda P. , Kroupa J. , Ošmera B. , Pošta S.
Published: May 2009

The present paper points toward the possibility of reducing the proportion of analog processing in an apparatus employed to measure the neutron and photon energy spectra. The digitization of the detector output pulses makes it possible to process the information contained in the pulses either instantaneously or subsequently. The present paper deals with the method of digitizing the leading edge of the pulses generated by a stilbene organic scintillator or an NE-213 scintillator. The neutron versus gamma discrimination can be carried out on the basis of the pulse leading edge duration. Coping with this task requires a digitizer featuring quite a high sampling frequency, which must exceed 1 GHz. The requirements for the amplitude digitization frequency are less severe, however, the amplitude resolution must be better than 8 bits. Both of the above requirements can be met with present-day components. The digitization is expected to result in reducing the apparatus size and improving its functionality.
Functional Properties of Nanostructured Ti-50.0 at % Ni Alloys
Authors: Demers V , Brailovski V , Prokoshkin S , Inaekyan K , Bastarash E , Khmelevskaya I , Dobatkin S
Published: May 2009

Ti-50 at % Ni alloy wire is subjected to cold-rolling (true strain e=0.3-1.9) and post-deformation annealing (200–700°C range). For all levels of cold work, the maxima of recovery strain and stress are obtained after annealing in the 350–400°C range. For the moderately-to-high cold-worked material (e=0.3-0.88), this annealing leads to polygonization, while for the severely cold-worked one (e=1.9), to the material nanocrystallization (grains of 50–80 nm in size). Nanocrystallized alloy generates 30 % higher recovery stresses (up to 1450 MPa) and 10% higher completely recoverable strains (more than 8 %) as compared to the polygonized alloy, while having comparable mechanical properties in tension.
Development of an ASTM Method for Measurement of the Extensional Viscosity of Agricultural Spray Solutions
Authors: Dexter Robin W.
Published: May 2009

Polymeric drift control agents are used to modify the droplet size distribution of pesticide sprays. These agents function by increasing the extensional viscosity of the spray liquid, enabling it to resist disruption as it emerges from the spray nozzle, usually leading to an increase in the median droplet diameter of the spray droplets. Extensional viscosity is often the most important physical property controlling the spray droplet size, especially when soluble polymers are present, but methods available for measurement of extensional viscosity of dilute solutions are complicated and are not generally available. This paper describes a simple, portable apparatus that can detect and quantify a relative extensional viscosity (screen factor) that is useful in evaluating the properties of drift control agents. The apparatus has been used to determine the screen factors of test substances used by the Spray Drift Task Force and to correlate them with independent measurements of extensional viscosity obtained using a Rheometrics RFX Extensional Rheometer. The method has been adopted as ASTM Method E 2408-04, “Relative Extensional Viscosity of Agricultural Spray Tank Mixes.”
Compatibility Testing of Multi-Vehicle Coolant Chemistries
Authors: Skrobul Anthony P. , Balfe Steven L. , Alverson Fred C.
Published: May 2009

Multi-vehicle or universal coolants, or both, have been introduced into the marketplace to satisfy the wishes of mass merchandisers, automotive garage and repair shops, quick oil change establishments, and the general public for a convenient single coolant for use in the myriad makes and models of vehicles. Universal coolants are recommended for top off, as well as complete drain and fill of the customer’s cooling system, regardless of the color or inhibitor chemistry of coolant already in use. Coolant mixing, and potential compatibility issues, will result for the top-off scenario, but may also be of concern following coolant system flush-and-fill. However, there are currently no standard compatibility tests to define satisfactory compatibility when coolants of different chemistry are mixed. Previous work to establish compatibility of coolant mixtures documents that potential coolant deterioration of the corrosion protection may occur in the ASTM D 4340 [1] Aluminum Heat-Rejection Test when mixing coolants with different additive chemistries. Compatibility testing has been conducted on various universal coolants with traditional high silicate, traditional low silicate, hybrid (phosphate free), hybrid (phosphated), and OAT-only technologies. This paper provides results of the coolant compatibility tests and correlation of coolant chemistry with coolant performance in these tests.
Fast Scan Differential Scanning Calorimetry Distinguishes Melting, Melting-Degradation/Sublimation and Thermal Stability of Drugs
Authors: Riga Alan T. , Golinar Michael , Alexander Kenneth S.
Published: May 2009

In order to establish a structure and property (melting and oxidative or thermal degradation, or both) relationship for a United States Pharmacopeias (USP) set of standard drugs, they were evaluated by fast scan differential scanning calorimetry. A critical problem in characterizing the endothermic melting of a drug is to determine the melting range and if a chemical melts and immediately degrades. The stability of standard drugs is based on a comparison of their thermal properties at widely varying ramp or heating rates from 10 to 100°C/min. A stable crystalline drug has an obvious melting endotherm followed by a stable baseline. An unstable crystalline drug melts and immediately degrades as viewed by a shifting melt endotherm with heating rate. The USP thermally stable standards evaluated in this study include vanillin (melt temperature, Tm, 80.4°C), acetanilide (Tm, 114°C), acetophenetidin (Tm, 135°C), sulfanilamide (Tm, 165°C), sulfapyridine (Tm, 191°C), and caffeine (Tm, 235°C and Tsublimation, <220°C). In addition to the USP samples a number of commercial and model drugs, like benzoic acid (Tm, 122°C and Tsublimation, <120°C), lidocaine.HCl and procaine.HCl were also examined. Their melt profiles were ranked as stable or unstable post fusion by the fast scan DSC technique and are reported.
Effect of Chemical Admixtures on Rheology of Cement Paste at High Temperature
Authors: Al-Martini S. , Nehdi M.
Published: May 2009

Placement of cement-based materials in hot weather conditions encounters many problems due to the rapid evaporation of mixing water and the accelerated hydration of cement. Such materials are also adversely affected at elevated temperatures by an increased water demand, shorter setting time, and more rapid slump loss. These problems can be mitigated using adequate chemical admixtures. However, technical data on such admixtures are commonly developed at normal temperatures, and there is a real need to investigate their performance at hot temperatures. In the current research, the rheological properties of portland cement pastes with a water-cement ratio (w/c) of 0.35 and 0.50 are investigated at different temperatures in the range of 20 to 45°C using an advanced shear-stress/shear-strain controlled rheometer. The influence of water-reducing and retarding admixture, polycarboxylate, naphthalene sulfonate, and melamine-based high-range water-reducing admixtures (HRWR) in addition to mid-range water-reducing admixtures (MRWR) on the rheological properties of cement paste at various temperatures was also examined. The paper aims at formulating recommendations for the effective use of chemical admixtures at high temperature, which should enhance the rheological properties of cement-based materials in hot weather conditions.
Estimation of the Osteolytic Potential of Noncrosslinked and Crosslinked Polyethylenes and Ceramic-on-Ceramic Total Hip Prostheses
Authors: Tipper JL , Galvin AL , Ingham E , Fisher J
Published: May 2009

There is currently considerable interest in the wear debris and osteolytic potential of different types of bearings used in total joint replacements. The aim of this study was first to characterize the wear and wear particles generated from two different grades of UHMWPE acetabular cups with different levels of crosslinking in a hip joint simulator. Secondly, the results for the polyethylenes were compared to an alumina ceramic-on-ceramic hip prosthesis. The wear rates of the two noncrosslinked material types were very similar at 49±8 mm3 per million cycles for the GUR 1020 and 45.6±1.4 mm3 per million cycles for the GUR 1050. Moderate crosslinking (4 MRad) significantly (P<0.05) reduced the wear rate of the GUR 1020 material by 30 % to 35±9 mm3 per million cycles. High levels of crosslinking of GUR 1050 (10 MRad) produced a highly significant (P<0.01) 80 % reduction in wear volume. Although reduced wear volumes were observed with moderate levels of crosslinking for the 4 MRad GUR 1020 material, little benefit was conveyed by crosslinking, in terms of predicted overall biocompatibility and estimated osteolytic potential. Introducing high levels of crosslinking (10 MRad) into the GUR 1050 material reduced wear and osteolytic potential by up to five-fold compared to the other GUR 1050 materials. However, compared to the noncrosslinked and moderately crosslinked GUR 1020 materials, the highly crosslinked GUR 1050 UHMWPE had only a two-fold lower osteolytic potential. The alumina ceramic-on-ceramic hip prostheses produced extremely low wear rates under both standard and microseparation simulation conditions, and consequently the osteolytic potential of the alumina bearings was estimated to be >20-fold lower than the highly crosslinked polyethylene.
A Comparison of Membrane Technologies for Engine Coolant Recycling
Authors: Hudgens R. , Schmidt E. , Williams M.
Published: May 2009

Recycling of used engine coolants containing ethylene glycol and other glycols would appear to be well established, particularly for reverse osmosis and nanofiltration membrane, electrodialysis, and distillation-based processes. Both literature and recycling facilities indicate success in employing these techniques. However, many recyclers, particularly those employing a single treatment technology, are not capable of producing recycled product meeting original equipment manufacturer (OEM) requirements for coolant, and these typically fall far short of approaching virgin (nonrecycled) coolant quality. In addition, some recycling facilities have produced and marketed product that led to coolant system damage and engine failure, either as a result of not sufficiently removing contaminants or inadequately reformulating with corrosion inhibitors and other additives. The danger of process upsets resulting in inadequate product is particularly high for those facilities that receive feeds with varying contaminant levels and coolants containing a range of corrosion inhibitors and additives (silicates, organic acids, etc.). However, no study to date has focused on a fundamental assessment of the separation characteristics and interactions of the various classes of coolant technologies with the commercially available reverse osmosis, nanofiltration, and electrodialysis ion exchange membranes typically seen in recycling operations. This study presents results of a comprehensive evaluation of the separation characteristics of a wide range of these membranes with a wide range of coolant types. In particular, the study examined production rate characteristics, inhibitor and other additive separation, and contaminant removal for reverse osmosis, nanofiltration, and electrodialysis. Residual inhibitors remaining in the recycled coolant are examined, with guidance provided on how these residuals might affect coolant reformulation and performance.
Comparison of Bench Test Methods to Evaluate Heavy Duty Coolant Thermal Stability
Authors: Chen Yu-Sen , Hudgens R. Doug , Eaton Edward R.
Published: May 2009

The past 10 to 15 years have seen a dramatic change in heavy duty coolants and cooling system maintenance practices. Controversy exists about the relative merits of newer organic acid (OAT) coolants and more conventional products, especially in the area of thermal stability. Coolant life has been extended from two years/240 K miles to at least five years/600 K miles. It is not uncommon for the same charge of coolant to remain in the cooling system until engine rebuild. Further, there has been an equally significant increase in the coolant service intervals. Reinhibition of the coolant was once tied to the oil change interval at 15 to 25 K miles. Now this additive addition has been extended in many cases to one year/150 K miles to two years/300 K miles. • Along with these dramatic increases in coolant life and service interval, strategies to reduce exhaust emissions such as EGR have increased and will continue to increase coolant temperatures. Sorting out coolant stability issues in the field is both expensive and time consuming. Further, it is very difficult to control a field test so as to obtain reliable data. In this environment, a bench test method that can quickly simulate high temperature, severe field service conditions is of vital importance. This paper compares four bench test methods as far as their ability to sort out thermal stability issues based on results from five coolants representing different additive packages and glycol qualities.
High-Altitude Testing and Evaluation of Liquid Pharmaceutical Glass and Plastic Bottles to Detect Leaks
Authors: Singh S. P. , Burgess G. , Singh J. , Lockhart H.
Published: May 2009

This paper discusses the impact on package integrity of high-altitude shipments of glass and plastic bottles. High altitudes are encountered when trucks travel over mountain passes and when cargo and feeder aircraft transport packages in nonpressurized or partially pressurized cargo holds. This is the second research study conducted on liquid product shipments. The first was done on liquid hazardous material combination packaging. The testing of pharmaceutical packaging is critical since the integrity of the product may be compromised during shipping and handling. Current shipping tests performed in labs do not account for simultaneous pressure changes and vibration. This study shows that packages currently being used for shipments of liquid pharmaceuticals that are tested to existing ASTM and ISO shipping tests are often inadequate, and can result in a significant number of leakers. Testing under combined vibration and pressure is necessary to ensure integrity.
The Relevance of Drop Tester Accuracy
Authors: Singh Jay , Vorst Keith , Singh S. Paul , Lao Matt
Published: May 2009

ASTM D 5276-98 “Standard Test Method for Drop Test of Loaded Containers by Free Fall,” [1] was written as the general test specification for permitting free-fall drop tests for packaged products. One of the fundamental characteristics for drop testers used to perform ASTM D 5276 is that they must produce a flat drop with tolerance limit set at ±2 deg. For drops other than flat drops, such as edges and corners, tolerance limits of ±5 deg have been specified. Although most drop testers are calibrated during manufacturing, they are often not checked for accuracy at their lab locations. This is primarily due to the lack of a calibration standard. This paper investigates the importance of drop test accuracy and reports observations, measurements, and documentation of changes in acceleration and velocity change measured on a test specimen as it is subjected to drops with increasing deviation from the desired impact orientation. A statistical analysis of accelerations as impact orientations deviated is provided and statistical trends in the data as impact angles change are reported. The results suggested that the existing tolerances for performing drops within ±2 deg as recommended by ASTM D 5276 are acceptable for flat drops and the tolerances for performing edge and corner drops within ±5 deg are not acceptable as they can result in larger deviations as the offset is increased beyond ±2 deg.
Novel Adjuvants for Targeting Pesticide Delivery
Authors: Penner Donald
Published: May 2009

Water repellent adjuvants increase the surface tension in contrast to surfactants that decrease surface tension of spray solutions. Increasing the surface tension spray droplets could potentially bounce through the plant foliage and canopy to target sites below. In this study organosilicone water repellents were applied with the herbicide, flumioxazin, and the insecticides, permethrin and carbaryl in greenhouse trials. Foliar retention was determined with the addition of Chicago sky blue dye which could be measured spectrophotometrically. Only the inclusion of DC1-6184 consistently reduced foliar retention of the various spray solutions on the spectrum of test plants.
Strength of Quasi-Isotropic Co-Cured Composite Joints Under Quasi-static and Fatigue Loading
Authors: Tan Xinyuan , Armanios Erian
Published: May 2009

Three composite joint configurations, namely, the straight laminate (SL), the single lap, and the single nested overlap (SNO) joints are investigated to ascertain the improvement of the SNO joint over the single lap joint under quasi-static and cyclic loading. The SNO joint is a co-cured composite joint design proposed previously, while the SL represents a perfect joint and serves as an upper bound for static strength and fatigue life comparisons. Stress-number curves are generated based on constant amplitude tension-tension cyclic loading at a frequency of 5 Hz and stress ratio (R) of 0.1 for quasi-isotropic graphite/epoxy (IM7/8551-7) joints. The maximum fatigue load is varied between an average of 70-90 % UTS for SL, 20–80 % ultimate tensile strength (UTS) for single lap joints and 40–95 % UTS for SNO joints. Fatigue run-out is defined at 1×106 cycles. The fatigue strength improvement of SNO joint is ascertained quantitatively through two indicators. Three quasi-static acoustic emission (AE) count peaks were identified during monotonic loading before eventually reaching a maximum at ultimate failure. The cumulative AE count peaks are used as a collective measurement of the significant damage event incurred under specific loading and subsequently correlated to the fatigue performance of each of these three joint configurations.
Sizing for the Clothing Industry Using Principal Component Analysis—An Australian Example
Authors: Veitch D. , Veitch L. , Henneberg M.
Published: May 2009

Principal component analysis was used to condense twelve anthropometric measurements into the first two principal components, which maximize information relevant to setting up a size and shape specification for the development of well-fitting apparel patterns, in this case for the manufacture of a bodice. The use of only two principal components allows for the specification of a practical sizing system. The database for the work consists of 54 measurements taken from 1330 adult women ranging in age from 18 to 70 + years measured in six capital cities in Australia in 2002 and 2004. The twelve measure subset was chosen by an experienced apparel pattern maker to be most relevant for a construction of a bodice pattern. Additionally, the measures were ordered in importance using all pair wise comparisons. This aspect of the work is essential in maximizing the retention of information using only two numbers. A new feature uses the scale dependency of principal component analysis to influence the accuracy of the reconstructed data using only the first two principal components. The paper defines 36 categories: twelve sizes and three shapes in each size. Percentages of women in the 36-size shape groups are determined. In as far as the sample of 1330 women is representative of the Australian population, the percentages provide valuable information for the apparel industry. The main purpose of the paper is to provide an example of how it is possible to improve sizing for clothing based on anthropometric body measurements in a manner acceptable to the apparel industry. The paper shows the body scans of a subset of nine actual women who illustrate the size and shape variations existing in this sample.
Use of a Soil Surfactant with Fungicides for Control of Fairy Ring Disease in Turfgrass
Authors: Fidanza M. A. , Wong F. P. , Kostka S. J. , McDonald S. J.
Published: May 2009

Fairy ring is the common name for a complex disease of turf encompassing the appearance of mushrooms, circles of stimulated grass, or rings of damaged or dead turfgrass maintained for lawns, athletic fields, or golf courses. Type-I fairy ring is especially destructive due to the development of water repellent or hydrophobic soil conditions and the subsequent decline and damage to the existing turfgrass. Fairy ring management strategies, particularly the control or suppression of Type-I fairy ring symptoms, has been inconsistent in effectiveness. The objective of this field study was to evaluate the efficacy of fungicides recommended for fairy ring control when applied alone and with a soil surfactant. This research was conducted on cool-season turfgrass in California in 2005, and in Pennsylvania in 2006. The same treatments were applied at both locations. The four fungicide treatments were evaluated at 620 g active ingredient (a.i.) azoxystrobin∙ha-1, 9757 g a.i. flutolanil∙ha-1, 310 g a.i polyoxin-D∙ha-1, or 558 g a.i. pyraclostrobin∙ha-1. Each fungicide was applied alone and in a tank-mix combination with the modified alkylated polyol soil surfactant (100 % concentration) at 19 L product∙ha-1. All treatments were applied at two water carrier volumes of 814 and 1628∙ L∙ha-1. At both locations, Type-I fairy ring symptoms were noticeably reduced in plots treated with fungicides plus soil surfactant at either water carrier volume versus plots treated with fungicides alone applied at 814 L water carrier ha-1. Therefore, the consistently best overall treatment for the control or suppression of Type-I fairy ring symptoms was fungicides plus soil surfactant at either water carrier volume. The application of plant protection products at the lower water volume is preferred by turfgrass managers and practitioners; thus the utility of soil surfactants applied with fungicides is a useful strategy for the chemical control of fairy ring in turf.
Glyphosate Adjuvant Formulation with Glycerin
Authors: Elsik Curtis M. , Stridde Howard M. , Tann R. Scott
Published: May 2009

The development of many crops with glyphosate tolerance has created a large demand for glyphosate herbicide formulations. Commercial aqueous solution glyphosate formulations usually contain a surfactant along with other formulation additives. The surfactant can function to help the spray solution wet the weed surface, and can also help potentiate the active ingredient. The other formulation ingredients usually include materials that function as humectants, antigelling agents, and antifreeze agents. Various traditional petrochemical derivatives have been used to achieve these effects. In this paper glycerin, a renewable natural material provides all of the nonsurfactant excipient properties. The advent of biodiesel production has created a surge in the production of glycerin. It has been found that this crude glycerin can be incorporated into commercial aqueous glyphosate formulations and can replace the traditional petrochemical derivative constituents. The glycerin functions as the humectant, antigelling agent, and antifreeze agent. This paper deals with the modifications and specifications necessary to achieve a suitable finished glyphosate product, as well as the performance results observed from field trials with the final formulation.
Development of Fast Dissolving Concentrated Gibberellin Water Soluble Granular Formulations
Authors: Devisetty Bala N. , Warrior Prem , Menendez Ricardo , Beach Mark , Heiman Daniel
Published: May 2009

Gibberellins, a major group of naturally occurring plant hormones, are diterpenoid acids, known to influence a range of plant developmental processes including stem elongation, germination, dormancy, flowering, sex expression, enzyme induction, fruit size and quality, and leaf and fruit senescence. Gibberellins are commercially produced by fermentation of natural fungus, Gibberella fujikuroi. The most commonly used Gibberellic acid, GA3, is primarily formulated as solutions (2 to 5 % in isopropyl alcohol, 10 % in methyl alcohol), as 5 to 20 % wettable or soluble powders, or both, as 3.1 % soluble granules or as 1 to 10-g effervescent tablets. The other frequently used gibberellins, GA4+7, are primarily formulated as 1 to 4 % solutions either in tetrahydrofurfuryl alcohol (THFA) or in propylene glycol. Of the solvents currently used, isopropyl alcohol and methyl alcohol offer severe disadvantages such as flammability, toxicity, and restrictions in manufacturing, packaging, labeling, transportation, and warehousing. The THFA used in some of the formulations is considered corrosive to the eye and skin. Low solubility of gibberellins in propylene glycol does not permit solution formulations with greater than 2 % wt/wt gibberellins. The powder formulations are not user friendly and require quite a long time to achieve true solubility of the active component in tank mixes. Due to low solubility and undesirable hydrolysis, it has not been possible to formulate gibberellins in aqueous systems. This paper will present formulation studies leading to the development of stable, high potency (GA3 at 40 % wt/wt and higher; GA4+7 at 10 % wt/wt and higher), dust free, instantly water wettable, dispersible, and soluble Gibberellin plant growth regulator granular formulations by low pressure extrusion methodology. Field biological efficacy studies on grapes showed concentrated water soluble granular formulation either equivalent or superior to the standard powder formulation.
Additive and Base Oil Effects in Automatic Particle Counters
Authors: Michael Paul W. , Wanke Thomas S. , McCambridge Michael A.
Published: May 2009

The U.S. Military specifies the use of Mil-PRF-2104 engine oil in the hydraulic system of certain nontactical military vehicles. Skid-steer loaders and other heavy equipment also use engine oils in their hydraulic systems. These vehicles are required to meet roll-off cleanliness specifications in order to improve hydraulic equipment reliability. Automatic particle counters are used to verify the cleanliness of these systems. Occasionally, particle counters detect phantom particles that cannot be removed by filtration. This paper examines the possible role of base oil and additive selection in the appearance of phantom counts. Filtered Group I and Group III base oils were doped with the components of an engine oil formulation. Particle levels were monitored before and after filtration using an on-line automatic particle counter. The results show that base oil selection has minimal bearing upon appearance of phantom counts while additive selection is a significant factor. Results from three different particle counters are compared. Two laser particle counters that operate by the light-blockage principle were found to produce phantom counts from polydimethylsiloxane antifoam additives. A direct-imaging laser particle counter classified antifoam particles as water droplets and was less susceptible to phantom particle interferences from silicone antifoam additives.
Retrospective Dosimetry of Fast Neutrons Focused on the Reactions 93Nb(n,n′)93Nbm and 54Fe(n,p)54Mn
Authors: Voorbraak W. P. , Kekki T. , Serén T. , Van Bockxstaele M. , Wagemans J. , Woittiez J. R.W.
Published: May 2009

An overview is given of practices for “retrospective” dosimetry based on extraction and counting of niobium and manganese present in typical pressure vessel materials. The main problem of counting structural materials is the overwhelming presence of the nuclide 60Co in the gamma-ray spectra of irradiated materials. Chemical separation of niobium and manganese is needed to determine the induced 93Nbm and 54Mn activities. Procedures have been developed for retrospective dosimetry applicable at normally equipped radiochemical laboratories. Chemical separation procedures have been applied followed by determination of the amount of niobium in dissolution after separation. Special attention has been given to the accurate counting of the very weak X rays of 93Nbm. Different techniques have been applied. Advantages, disadvantages, and the accuracy that can be achieved are discussed. Special attention has been given to the maximum accuracy that can be reached and the minimum amount of niobium that has to be collected to reach this accuracy.
Measurement of Corrosion Potentials of the Internal Surface of Operating High-Pressure Oil and Gas Pipelines
Authors: Demoz Alebachew , Papavinasam Sankara , Michaelian Kirk , Revie R. Winston
Published: May 2009

Corrosion potential is a fundamental electrochemical parameter critical to understanding the thermodynamic aspects of corrosion. Many corrosion theories are based on corrosion potentials. Corrosion potential is routinely and easily measured in the laboratory. In order to transfer this scientific knowledge from the laboratory to the field, it is necessary to determine the corrosion potential under operating field conditions. In this paper, the unique challenges measuring corrosion potentials in an industrial environment are described using measurements of the corrosion potentials of the internal surfaces of pipelines as examples.
Skiing and Snowboarding Injuries in Greece: A Two-Year Case-Control Study
Authors: Zacharopoulos Athanasios N. , Tzanakakis Nikolaos E. , Douka Maria I.
Published: May 2009

Purpose: To examine the incidence, types and patterns of snow sports injuries at Greek ski resorts. Material and Methods: Prospective case-control study at two major Greek ski resorts during 2004-5 and 2005-6 winter seasons, involving 978 injured skiers and snowboarders who asked for medical help and 775 uninjured controls randomly selected. The controls comprised every fifth person at the waiting queue towards the lifts, during weekdays, weekends and holidays, in all weather conditions. Results: The injury rate was 6.05 injuries per 1000 skier days, while 72.7 % of injuries occurred during alpine skiing and 27.3 % during snowboarding. Lower limb injuries were the commonest among skiers 43 % and females had a significant higher prevalence of injury than males (59 % versus 39 %). Snowboarders sustained more frequently upper limb injuries (49.2 %). Ligament sprains (22 %) and contusions (17.4 %) were commonest among skiers, whereas fractures (20.5 %) and contusions (15.4 %) were commonest among snowboarders. Knee and wrist injuries had statistically significant differences between skiers and snowboarders: knee 33.1 % versus 13.3 % and wrist 6.8 % versus 20 %. Most of injuries occurred during “free riding” (65 %), while the second cause of injury was collision for skiers (15.6 %) and jumps for snowboarders (23.5 %). Almost one out of five injuries (19.8 %) was lift related and 23.4 % of the lift related injuries happened when riding with an instructor. Most of injuries occurred at the end of the skiing day. Conclusions: Despite the high incidence of snow sports injuries in Greece the patterns and specific rates of injuries are similar to those previously reported in comparable studies. Many injuries were lift related, most of the injuries happened at the end of the skiing day and many people were injured when skiing/boarding with an instructor. So there is much room to update skiing safety in Greece providing safer slopes and adequate instruction.
Head Kinematics During Experimental Snowboard Falls: Implications for Snow Helmet Standards
Authors: Richards Darrin , Carhart Michael , Scher Irving , Thomas Reed , Hurlen Natalie
Published: May 2009

A study by Nakaguchi and Tsutsumi [“Mechanisms of Snowboarding-Related Severe Head Injury: Shear Strain Induced by the Opposite-Edge Phenomenon,” J. Neurosurg, Vol. 97, 2002, pp. 542–548] showed that 68 % of all snowboarders’ head injuries were associated with backward falls, with beginner and intermediate snowboarders constituting the majority of the injured. We previously fabricated a test apparatus that replicated the fall kinematics of a snowboarder during a back-edge trip. A Hybrid-III anthropomorphic test device (ATD) outfitted with a snowboard and snowboarding gear was accelerated to a typical intermediate snowboarder’s speed (30.5 ± 1.5 kph) and tripped resulting in a backward fall that terminated in a head-to-slope impact. This test protocol produced repeatable fall kinematics under realistic on-slope conditions. In this study, we characterized the fall kinematics and quantified head velocity in order to evaluate the helmet energy management requirements associated with a back-edge trip. Digital high-speed video recorded at 500 frames per second was used to quantify the snowboarder’s head kinematics: (i) prior to the trip; (ii) during trip phase; (iii) during free fall; and (iv) at ground impact. Translational energy of the ATD was rapidly converted to a combination of linear and angular energy during the trip phase. Although the speed of the ATD’s center of gravity decreased during the trip phase, the test data showed the absolute speed of the head increased rapidly during the fall as a result of the body’s induced angular rotation. The mean head velocity normal to the slope increased from approximately zero at fall initiation to as much as 37.1 kph during the fall (122 % of the initial velocity), and was 29.1 kph at snow contact (95 % of the initial velocity). Resultant head velocity peaked at 54.3 kph (178 % of the initial velocity), and was 38.2 kph at snow contact (125 % of the initial velocity). The data presented here may be useful for assessing drop height requirements for snow helmet evaluations.
Evaluation of Residual Stress Effects on Brittle Fracture Strength Based on Weibull Stress Criterion
Authors: Yamashita Yoichi , Minami Fumiyoshi
Published: May 2009

This paper studies the method for estimating the residual stress effects on brittle fracture of structural steel based on the Weibull stress criterion. First, brittle fracture tests were conducted for four-point bend notched specimens with and without compressive preloading. It is shown that the compressive preloading apparently decreases the critical crack tip opening displacement (CTOD). The critical CTOD of the preloaded specimen can be predicted from monotonically loaded test results based on the Weibull stress criterion. It has been found that the Weibull stress is an effective fracture parameter for brittle fracture initiation under tensile residual stress. Second, using wide plate specimens with and without welding residual stress subjected to uniform tension and three-point bend fracture toughness specimens, welding residual stresses effect on the brittle fracture strength is investigated. Experiments show that the critical CTOD of wide plate with welding residual stress is significantly smaller than that without residual stress. Constraint loss effect on CTOD of wide plate can be assessed by the equivalent CTOD ratio β. β is defined as β=δ3PB/δWP, where δ3PB and δWP are CTODs of the standard fracture toughness specimen and wide plate, respectively, at the same level of the Weibull stress. Fracture assessment result using β is shown within the context of failure assessment diagram. An excessive conservatism observed in the conventional procedure (β=1) is reasonably reduced by applying the equivalent CTOD ratio β.
Hydrogen/Plasticity Interactions at an Axial Crack in Pipeline Steel
Authors: Dadfarnia M. , Sofronis P. , Somerday B. P. , Robertson I. M.
Published: May 2009

The technology of large scale hydrogen transmission from central production facilities to refueling stations and stationary power sites is at present undeveloped. Among the problems which confront the implementation of this technology is the deleterious effect of hydrogen on structural material properties, in particular at gas pressure of 15 MPa which is the desirable transmission pressure suggested by economic studies for efficient transport. To investigate the hydrogen embrittlement of pipelines, a hydrogen transport methodology for the calculation of hydrogen accumulation ahead of a crack tip in a pipeline steel is outlined. This work addresses the interaction of hydrogen with an axial crack on the inside surface of the pipe. The approach accounts for stress-driven transient diffusion of hydrogen and trapping at microstructural defects whose density evolves dynamically with deformation. The results address the effect of hydrostatic constraint, stress, and plastic strain on the time it takes for the steady state hydrogen profiles to be established.
Tabletop Jumping: Engineering Analysis of Trajectory and Landing Impact
Authors: Shealy Jasper , Stone Fred
Published: May 2009

This study is an engineering analysis of skiers and snowboarders jumping what is known as a mid-sized tabletop feature at a ski resort. The analysis specifically looks at the trajectories and landing impacts of individuals while jumping mid-sized tabletop features (deck lengths 20 to 30 ft) at a ski resort. For the trajectory analysis, out of a total of 117 jumps by skiers and snowboarders that were observed, 57 jumps were analyzed using a radar gun to determine actual speed on the ramp, digital photography to document flight paths and landing points as well as jumper body position at the moment of take-off. For the impact analysis, a total of 31 jumps by an instrumented subject were videotaped; the landing impacts for 21 of these jumps were measured with triaxial accelerometers to measure the impact resulting from the landing at the boot top, chest, and head levels. With respect to trajectory analysis, the study concludes that simply knowing the ramp angle and take-off speed is not a sufficient dataset to predict where the jumper will land; alternatively, knowing the ramp angle and the landing point is an insufficient dataset to predict the take-off speed. The specific actions of the jumper with regard to raising or lowering the jumper’s center of mass while on the last part of the take-off ramp can significantly alter the effective take-off angle and subsequent flight trajectory. For the jumps observed in this study, the jumpers were able to routinely add or subtract as much as 15° to the actual take-off ramp angle, resulting in effective take-off angles much larger or smaller than the measured take-off angle. With respect to impact analysis, the study concluded that for jumps similar to the those observed in the trajectory analysis, when the jumper lands in an upright controlled manner, the resulting impact (measured in G units) at the boot level ranged from 50 to 100 Gs, with a mean of 75 Gs, it averaged 4.7 Gs at the chest and only 2.5 Gs at the head.
Injury Trends in Norwegian Ski Resorts in the 10 Year Period 1996–2006
Authors: Ekeland Arne , Rødven Andreas
Published: May 2009

A central ski patrol-based registration of skiing and boarding injuries was performed by the Norwegian Ski Lift Association during the winter seasons 1996/1997–2005/2006. Totals of 31 175 injured skiers/boarders and 21.898 million skier/boarder days were recorded during the ten seasons, giving an injury rate of 1.4 injured per 1000 skier/boarder days. Most of the injuries occurred during alpine skiing (49–58 %). Snowboarding injuries peaked with 45 % in the middle of the period decreasing to 35 % the last two seasons. Telemark skiing and skiboarding each accounted for less than 10 % of the injuries. Wrist injuries were most common among injured snowboarders and knee injuries among injured alpine skiers. The percentage of knee injuries was almost twice as high for females compared to males throughout the period (p<0.001). The prevalence of lower leg fracture for injured alpine skiers ⩽12 years decreased from 20 % to 13 % in the period (p<0.001), whereas the corresponding prevalence for teenagers and adults was relatively stable at 3–5 %. Injuries in terrain parks increased to 20 % of all injuries at the end of the period. The use of helmets among injured skiers/boarders increased from 11 % to 44 % in the 10-year period (p<0.001), whereas the prevalence of head injuries decreased from 19 % to 17 % (p<0.003). In conclusion, the injury rate has been almost constant during the last six seasons in Norwegian ski resorts. The prevalence of lower leg fracture has decreased in injured alpine skiers ⩽12 years. The use of protective helmet has increased by injured skiers/boarders and the prevalence of head injuries has decreased.