bluuebunny/crossref_metadata_2025 huggingface dataset:
Vitamin D deficiency in patients with intellectual disabilities: prevalence, risk factors and management strategies
Authors: Frighi Valeria , Morovat Alireza , Stephenson Matthew T. , White Sarah J. , Hammond Christina V. , Goodwin Guy M.
Published: September 2014

Background

People with intellectual disabilities have a high risk of osteoporosis and fractures, which could partly be as a result of vitamin D deficiency.

Aims

To compare the serum vitamin D (25(OH)D) levels of 155 patients with intellectual disabilities under psychiatric care and 192 controls, investigate potential risk factors for vitamin D deficiency in people with intellectual disabilities and assess available treatments.

Method

Cross-sectional observational study followed by treatment evaluation.

Results

Almost twice as many patients with intellectual disabilities had vitamin D deficiency (25(OH)D <50 nmol/l) compared with controls (77.3%v.39.6%,P<0.0001). In the intellectual disabilities group, winter season (P<0.0001), dark skin pigmentation (P<0.0001), impaired mobility (P= 0.002) and obesity (P= 0.001) were independently associated with lower serum 25(OH)D. In most patients, 800 IU colecalciferol daily normalised 25(OH)D levels.

Conclusions

Vitamin D deficiency is highly prevalent in people with intellectual disabilities, partly because of insufficient exposure to sunlight. Screening and treatment strategies, aiming to reduce these patients' high fracture risk, should be introduced. Similar strategies may be required in other psychiatric populations at risk for fractures and with a tendency to spend excessive time indoors.
Precise control of plant stem cell activity through parallel regulatory inputs
Authors: Bennett Tom , van den Toorn Albert , Willemsen Viola , Scheres Ben
Published: September 2014

The regulation of columella stem cell activity in the Arabidopsis root cap by a nearby organizing centre, the quiescent centre, has been a key example of the stem cell niche paradigm in plants. Here, we investigate interactions between transcription factors that have been shown to regulate columella stem cells using a simple quantification method for stem cell activity in the root cap. Genetic and expression analyses reveal that the RETINOBLASTOMA-RELATED protein, the FEZ and SOMBRERO NAC-domain transcription factors, the ARF10 and ARF16 auxin response factors and the quiescent centre-expressed WOX5 homeodomain protein each provide independent inputs to regulate the number of columella stem cells. Given the tight control of columella development, we found that these inputs act in a surprisingly parallel manner. Nevertheless, important points of interaction exist; for example, we demonstrate the repression of SMB activity by non-autonomous action of WOX5. Our results suggest that the developmental progression of columella stem cells may be quantitatively regulated by several more broadly acting transcription factors rather than by a single intrinsic stem cell factor, which raises questions about the special nature of the stem cell state in plants.
From Pre-Elite to Elite: The Pathway Travelled by Adolescent Golfers
Authors: Hayman Rick J. , Borkoles Erika , Taylor Jamie A. , Hemmings Brian , Polman Remco C.
Published: September 2014

This study employed interpretative phenomenological analysis (IPA) to explore the lived experiences of eight high performing adolescent golfers who had all successfully travelled the path from novice to elite level status. By means of semi-structured qualitative interviews, participants answered questions centred on four key areas which explored their journey from pre-elite to elite adolescent status: initial involvement and continued participation in golf, the meaning of golf, golf environment and social support. Two super-ordinate themes emerged from participants accounts: Early Pre-Elite Sporting Experiences and Strategic Approaches to Develop Adolescent Golfing Excellence. The study provides key insights into individual, social and environmental factors that enabled pre-elite adolescent golfers to make a successful transition to the elite pathway, and highlights plausible factors that may make a difference whether an athlete becomes elite or not. The findings will help coaches, policy makers and sport psychologists more effectively support emerging talent in golf.
Golden Section’s Numerical Approximations in Terms of Graphics and Application
Authors: Сафиулина  , Safiulina Yu. , Шмурнов  , Shmurnov V.
Published: September 2014

Golden proportion’s graphic plotting methods have

been considered. A history related to gradual development of views

on Golden section problem as «law of beauty» is traced. Numerical

ratios most frequently used in the art for approximations related to

division of a line segment in extreme and mean ratio have been

provided. An original scheme for «Golden rectangle» construction

based on application offered by Leonardo da Vinci for the quadrature of circle problem solution has been proposed.
Pediatric Population Reference Value Distributions for Cancer Biomarkers and Covariate-Stratified Reference Intervals in the CALIPER Cohort
Authors: Bevilacqua Victoria , Chan Man Khun , Chen Yunqi , Armbruster David , Schodin Beth , Adeli Khosrow
Published: September 2014

BACKGROUND

Cancer biomarkers are commonly used in pediatrics to monitor cancer progression, recurrence, and prognosis, but pediatric reference value distributions have not been well established for these markers. The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) sought to develop a pediatric database of covariate-stratified reference value distributions for 11 key circulating tumor markers, including those used in assessment of patients with childhood or adult cancers.

METHODS

Healthy community children from birth to 18 years of age were recruited to participate in the CALIPER project with informed parental consent. We analyzed serum samples from 400–700 children (depending on the analyte in question) on the Abbott Architect ci4100 and established reference intervals for α-fetoprotein (AFP), antithyroglobulin (anti-Tg), human epididymis protein 4 (HE4), cancer antigen 125 (CA125), CA15-3, CA19-9, progastrin-releasing peptide (proGRP), carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and total and free prostate specific antigen (PSA) according to CLSI C28-A3 statistical guidelines.

RESULTS

We observed significant fluctuations in biomarker concentrations by age and/or sex in 10 of 11 biomarkers investigated. Age partitioning was required for CA153, CA125, CA19-9, CEA, SCC, proGRP, total and free PSA, HE4, and AFP, whereas sex partitioning was also required for CA125, CA19-9, and total and free PSA.

CONCLUSIONS

This CALIPER study established a database of childhood reference intervals for 11 tumor biomarkers and revealed dramatic fluctuations in tumor marker concentrations between boys and girls and throughout childhood. In addition, important differences between the adult and pediatric population were observed, further highlighting the need for pediatric-specific reference intervals.
Modelling variation of needle density of Scots pine at high latitudes
Authors: Salminen Hannu , Jalkanen Risto
Published: September 2014

The relationship between apical extension and needle density and the effect of temperature and precipitation on needle density was modelled using data gathered from forty-nine felled sample trees in five stands of Scots pine (Pinus sylvestris L.) located along a latitudinal transect from the Arctic Circle up to the northern timberline. The lengths were measured and needle densities assessed from all annual shoots located above 1.3 metres using the Needle Trace Method (NTM), resulting, on average, in 39-year-long chronologies. The mean overall needle density was 7.8 short shoots per shoot centimetre. Needle-density variation in the measured data was mostly due to within-tree differences. Of the total variance, within-tree variation yielded 46%, between-tree 21%, and between-year 27%. The dependence of needle density on annual height growth was studied by fitting a multilevel model with random stand-, tree- and year-intercepts, the independent variables being tree age and height growth. There was a very strong negative correlation between height growth and needle density, and the proportion of between-year variance explained solely by height growth and age was 50%. The stand-wise residual variations and their correlations with the temperature and precipitation time series were further analysed with cross-correlation analysis in order to screen for additional independent variables. The only possible additional independent variable found was the precipitation of AprilâMay (precipitation of May in the two northernmost stands). When it was added to the multi-level model, the proportion of explained between-year needle-density variance was 55%, but the overall fit of the model improved only slightly. The effect of late winter and early spring precipitation indicates the role of snow coverage and snowmelt on the growing conditions in the three southernmost stands. In general, stand-level needle-density variation is mostly due to changes in height growth.
Geometrically accurate time series of archived aerial images and airborne lidar data in a forest environment
Authors: Korpela Ilkka
Published: September 2014

Reconstructing three-dimensional structural changes in the forest over time is possible using archived aerial photographs and photogrammetric techniques, which have recently been introduced to a larger audience with the advent of digital photogrammetry. This paper explores the feasibility of constructing an accurate time-series of archived aerial photographs spanning 42 years using different types of geometric data and estimation methods for image orientation. A recent airborne laser scanning (lidar) data set was combined with the image block and assessed for geometric match. The results suggest that it is possible to establish the multitemporal geometry of an image block to an accuracy that is better than 0.5 m in 3D and constant over time. Even geodetic ground control points can be omitted from the estimation if the most recent images have accurate direct sensor orientation, which is becoming a standard technique in aerial photography. This greatly reduces the costs and facilitates the work. An accurate multitemporal image block combined with recent lidar scanning for the estimation of topography allows accurate monitoring and retrospective analysis of forest vegetation and management operations.
Harvesting and transport of root biomass from fast-growing poplar plantations
Authors: Spinelli Raffaele , Nati Carla , Magagnotti Natascia
Published: September 2014

Recovery of tree root biomass can be attractive, since the stump-root system represents a substantial portion of the tree mass and its removal may prove instrumental to re-cultivation. Most available studies concern Nordic technologies, particularly suited to mature conifer stands. Unlike spruce, plantation poplar develops a deep taproot, whose extraction requires completely different methods. The aim of the study was to investigate poplar root recovery operations in plantations with time studies, and to determine the productivity and delivery costs of the operations. Seven operation systems developed to work with poplar plantations in Italian conditions were studied. Extraction and cleaning units were based on general-purpose prime movers. Under favourable conditions extraction and cleaning units achieved a very high productivity: 150 stumps per hour for the extraction unit and 170 for the cleaning unit. Delivered cost varied widely, ranging from 28 to 66 Euros Mg. Transportation was the most expensive single work task. It accounted for about 40% of the total recovery cost. Extraction and cleaning contributed approximately 25% each to the total cost, and loading 9%. Guidelines to recovery system improvement and efficient operation are provided.â1
Applying geostatistics for investigations of forest ecosystems using remote sensing imagery
Authors: Zawadzki Jaroslaw , Cieszewski Chris , Zasada Michal , Lowe Roger
Published: September 2014

Geostatistically based methods that utilize textural information are frequently used to analyze remote sensing (RS) images. The role of these methods in analyzing forested areas increased rapidly during the last several years following advancements in high-resolution RS technology. The results of numerous applications of geostatistical methods for processing RS forest images are encouraging. This paper summarizes such results. Three closely related topics are reviewed: 1) specific properties of geostatistical measures of spatial variability calculated from digital images of forested areas, 2) determination of biophysical forest parameters using semivariograms and characterization of forest ecosystem structure at the stand level, and 3) forest classification methods based on spatial information.
Temporal trends in chemical parameters of upland forest soils in southern Finland
Authors: Tamminen Pekka , Derome John
Published: September 2014

Changes in chemical soil properties during periods of 12 to 28 years were studied in 54 stands in southern Finland. Relative slopes (%/year) were calculated for the changes in soil variables in order to utilise all the sampling occasions (2â6) covered by the study period. Only the results of new analyses made on the soil samples could be used owing to unpredictable differences between the results of the original and new analyses. During the study period the acidity (pH, exchangeable acidity) of the organic layer had decreased, and the mineral soil had become more acidic only in terms of increased exchangeable aluminium concentrations. An increasing trend in the amount of soil organic matter best explained the acidity variables: it lowered acidity in the organic layer, but increased it in the mineral soil. Acid ammonium acetate extractable nutrients showed decreasing trends over time, apart from an increasing trend for sulphur in the 0â30 cm mineral soil layer. Total concentrations of most elements in the organic layer, including nitrogen and sulphur, also showed a decreasing trend. Changes in the soil variables could not be firmly connected to deposition, wood production or the amount of nutrients accumulated in woody tissues. However, the decrease in sulphur concentrations in the organic layer was clearly linked with the decrease in sulphur deposition in recent years.
Small-scale non-industrial private forest ownership in the United States: rationale and implications for forest management
Authors: Zhang Yaoqi , Zhang Daowei , Schelhas John
Published: September 2014

The transaction cost approach is used to explain why small non-industrial private forest (NIPF) ownerships are increasing in the U.S. We argue that the number of small NIPF owners have increased because: 1) a significant amount of forestland is no longer used economically if primarily for timber production, but rather for non-timber forest products and environmental services (particularly where population density is high), 2) when a person makes frequent use of non-timber products and services, owning forestland is more efficient for them because it saves the transaction costs involved in getting them from the market, 3) forestland parcelization takes place when non-timber value increases faster than timber value, and 4) marginal value for non-timber product is diminishing much faster than that for timber production. The paper also discusses implications of the parcelization of NIPF ownerships on forest management.
Survival-time analysis of white spruce during spruce budworm defoliation
Authors: Magnussen Steen , Alfaro René , Boudewyn Paul
Published: September 2014

Mortality and defoliation (DF%) in 987 white spruce (Picea glauca (Moench) Voss) trees were followed from 1992 to 2003 during an outbreak of the spruce budworm Choristoneura fumiferana (Clem.) in 15 white-spruce-dominated uneven-aged stands in the Fort Nelson Forest District near Prince George, British Columbia. Four stands were aerially sprayed with Bacillus thuringiensis (Bt). Defoliation and mortality levels were elevated in non-sprayed stands. The relationship between defoliation and survival-times was captured in a Cox proportional hazard model with a defoliation stress index (DSI), diameter (DBH), crown class (CCL), a random stand effect, Bt-treatment, and number of years of exposure to stand-level defoliation (DYEAR) as predictors. The DSI, optimized for discrimination between survivors and non-survivors, is the discounted sum of five lagged DF% values. Survival probabilities were predicted with a maximum error of 0.02. Hazard rates increased by 0.06 for every one point increase in DSI. CCL and random stand effects were highly significant. Bt-treatment effects were fully captured by DSI, CCL, and DYEAR.
Functions for estimating stem diameter and tree age using tree height, crown width and existing stand database information
Authors: Kalliovirta Jouni , Tokola Timo
Published: September 2014

The aim was to investigate the relations between diameter at breast height and maximum crown diameter, tree height and other possible independent variables available in stand databases. Altogether 76 models for estimating stem diameter at breast height and 60 models for tree age were formulated using height and maximum crown diameter as independent variables. These types of models can be utilized in modern remote sensing applications where tree crown dimensions and tree height are measured automatically. Data from Finnish national forest inventory sample plots located throughout the country were used to develop the models, and a separate test site was used to evaluate them. The RMSEs of the diameter models for the entire country varied between 7.3% and 14.9% from the mean diameter depending on the combination of independent variables and species. The RMSEs of the age models for entire country ranged from 9.2% to 12.8% from the mean age. The regional models were formulated from a data set in which the country was divided into four geographical areas. These regional models reduced local error and gave better results than the general models. The standard deviation of the dbh estimate for the separate test site was almost 5 cm when maximum crown width alone was the independent variable. The deviation was smallest for birch. When tree height was the only independent variable, the standard deviation was about 3 cm, and when both height and maximum crown width were included it was under 3 cm. In the latter case, the deviation was equally small (11%) for birch and Norway spruce and greatest (13%) for Scots pine.
Repeatability in automatic sorting of curved Norway spruce saw logs
Authors: Edlund Jacob , Warensjö Mats
Published: September 2014

Sawn wood from curved logs is prone to have cross grain and contain compression wood, both of which affect the dimensional stability. Different types of curvature can, however, have different effects on both the sawing process and board quality, which is why a standard measure of bow height alone is not enough to sort logs or set the log quality. The aim of this study was to evaluate the repeatability when sorting curved saw logs using a 3D log scanner. In the study, 56 logs were categorized into five different curvature types and four different degrees of curvature severity. The logs were run through a Rema 3D log scanner four times, and the external geometry was recorded. From the geometry data, variables describing log shapes were calculated and used to develop models using linear discriminant analysis, which was used to classify the logs according to curvature type. The accuracy and repeatability were evaluated for the classifications with Cohenâs simple Kappa coefficient. The results of this study showed that it is possible to sort logs by curve type using a 3D log scanner, although sorting by curve type was largely dependent on curve severity. The repeatability test determined that the chance of a curved log being graded identically two consecutive times was 0.40, measured as kappa.
Effectiveness of neutral RAPD markers to detect genetic divergence between the subspecies uncinata and mugo of Pinus mugo Turra
Authors: Monteleone Ignazio , Ferrazzini Diana , Belletti Piero
Published: September 2014

Fifteen populations of Pinus mugo subsp. mugo (shrub) and Pinus mugo subsp. uncinata (erect), located in the Alps, were investigated through genetic variation scored at 64 polymorphic RAPD loci. In addition, morphological traits of the female cones were analysed. According to AMOVA most of the genetic variation was found within populations (83.39%), and only 1.25% of it between subspecies. Populations differed in terms of their internal genetic variation, with Neiâs gene diversity ranging from 0.227 to 0.397. Morphological data showed differences between subspecies, although none of the populations showed full accordance with expectations. Significant correlation was found between matrices for geographical and morphological distances, while genetic distances were not correlated with any other aspect. The efficacy of morphological and RAPD markers in discriminating between subspecies, and the contribution of the results in relation to the preservation of biodiversity, are discussed.
A new heuristic method for solving spatially constrained forest planning problems based on mitigation of infeasibilities radiating outward from a forced choice
Authors: Bettinger Pete , Zhu Jianping
Published: September 2014

A new heuristic method to mitigate infeasibilities when a choice is forced into a solution was developed to solve spatially constrained forest planning problems. One unique aspect of the heuristic is the introduction of unchosen decision choices into a solution regardless of the resulting infeasibilities, which are then mitigated by selecting next-best choices for those spatial units that are affected, but in a radiating manner away from the initial choice. As subsequent changes are made to correct the affected spatial units, more infeasibilities may occur, and these are corrected as well in an outward manner from the initial choice. A single iteration of the model may involve a number of changes to the status of the decision variables, making this an n-opt heuristic process. The second unique aspect of the search process is the periodic reversion of the search to a saved (in computer memory) best solution. Tests have shown that the reversion is needed to ensure better solutions are located. This new heuristic produced solutions to spatial problems that are of equal or comparable in quality to traditional integer programming solutions, and solutions that are better than those produced by two other basic heuristics. Three small hypothetical forest examples illustrate the performance of the heuristic against standard versions of threshold accepting and tabu search. In each of the three examples, the variation in solutions generated from random starting points is smaller with the new heuristic, and the difference in solution values between the new heuristic and the other two heuristics is significant (p<0.05) when using an analysis of variance. However, what remains to be seen is whether the new method can be applied successfully to the broader range of operations research problems in forestry and other fields.
Finite morphisms to projective space and capacity theory
Authors: Chinburg Ted , Moret-Bailly Laurent , Pappas Georgios , Taylor Martin J.
Published: September 2014

We study commutative rings R for which all projective schemes over R have
finite morphisms to a projective space of R. We then use our results to define a new kind of capacity
for adelic subsets of projective flat schemes

X

{{X}}

over global fields. This capacity can be used to generalize the converse part of
the Fekete–Szegő Theorem.
Reengineering classic organic reactions using polymeric tools
Authors: Toy Patrick H.
Published: September 2014

Many of the most widely used reactions in organic synthesis suffer from drawbacks that can hamper their use. For example, the Mitsunobu, Wittig and Appel reactions all result in the formation of a full equivalent of triphenylphosphine oxide, which can be similar in polarity to the desired product, and thus be difficult to remove. Other reactions such as the Suzuki-Miyaura and Mizoroki-Heck reactions require the addition of numerous reagents, ligands and catalysts that can be laborious to separate from the targeted cross-coupled product. This review summarizes our recent work to address these issues by developing polymeric tools designed to simplify product isolation from these transformations.
Novel measures based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis
Authors: Mihailović Dragutin T. , Mimić Gordan , Nikolić-Djorić Emilija , Arsenić Ilija
Published: September 2014

We propose novel metrics based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis. We consider the origins of the Kolmogorov complexity and discuss its physical meaning. To get better insights into the nature of complex systems and time series analysis we introduce three novel measures based on the Kolmogorov complexity: (i) the Kolmogorov complexity spectrum, (ii) the Kolmogorov complexity spectrum highest value and (iii) the overall Kolmogorov complexity. The characteristics of these measures have been tested using a generalized logistic equation. Finally, the proposed measures have been applied to different time series originating from: a model output (the biochemical substance exchange in a multi-cell system), four different geophysical phenomena (dynamics of: river flow, long term precipitation, indoor 222Rn concentration and UV radiation dose) and the economy (stock price dynamics). The results obtained offer deeper insights into the complexity of system dynamics and time series analysis with the proposed complexity measures.
A New High-Pressure Triaxial Apparatus for Inducing and Tracking Hydro-Mechanical Degradation of Clayey Rocks
Authors: Pineda Jubert , Romero Enrique , Alonso Eduardo E. , Pérez Tomás
Published: September 2014

This paper presents the development of a new high-pressure triaxial apparatus specifically prepared for inducing and tracking the degradation of clayey rocks. Total suction—used to induce the hydraulic degradation—is applied with vapor transfer technique by controlling the relative humidity of air in contact with the material. The evolution of the degradation process along different hydro-mechanical stress paths is continuously tracked with bender elements, as well as with air or water permeability measurements on partially saturated or saturated states, respectively. Relevant test results on a low porosity clayey rock (Lilla claystone, Spain) are presented to evaluate the main capabilities of the new equipment. The results bring up the high sensitivity to water of the material, which is evidenced by the important reduction of shear wave velocity induced on first wetting and drying at low confining stress, as well as by the significant increase in the air permeability of the degraded material (around four orders of magnitude larger than the intact material). Test results also showed clear differences in the volume change and shear strength behavior of undisturbed, saturated, and degraded samples, highlighting the relevance of degradation on macroscopic behavioral features.
High-Speed Quenching of High Carbon Steel
Authors: Martínez-Cázares G. M. , Lozano D. E. , Guerrero-Mata M. P. , Colás R. , Totten G. E.
Published: September 2014

Medium and high carbon steels are usually quenched in polymer and oil in order to avoid cracking and distortion; however, recent studies have proved that it is possible to minimize cracking using water as a coolant of these steels by promoting extremely high cooling rates. By great agitation and velocity of quenchant, the vapor blanket is reduced or prevented during water quench, allowing uniform hardening of the surface. In this study, the cooling severity of a spray quenching system and a high-speed quenching chamber are studied. Cylindrical samples of AISI 304 stainless steel (20 mm in diameter and 100 mm length) were employed to characterize the cooling severity. Thermal data was acquired through K-type thermocouples placed in the sample at three positions, 1 mm below surface, mid-radius and at center of the specimen, connected to a data acquisition system. High thermal gradients were observed in both systems, being the high-speed chamber the severest cooling. The maximum cooling rate obtained at the surface was 470 and 300°C/s for the high-speed chamber and the spray system, respectively. In addition, 5160 spring steel samples were quenched for short times in both systems; the cooling was interrupted to avoid through transformation and to produce a case-core type microstructure. Different cooling times were used for the interrupted quenching to modify the martensite case thickness. No cracks were observed. Thermal results and microstructures are discussed.
Appraisal of Solution Heat Treatment on Elimination of Hafnium Rich γ–γ′ Eutectic and Prior Particle Boundary Precipitate in a Superalloy Powder
Authors: Oluwasegun K. M. , Olawale J. O. , Adeoye M. O. , Olorunniwo O. E. , Ige O. O. , Atanda P. O.
Published: September 2014

Near-net shape hot isostatic pressing (HIPping) in powder metallurgy (P/M) has been on the increase in the production of superalloys for aero and land based turbine disc applications. A critical challenge related to net-shape HIPping PM is the presence hafnium rich γ–γ′ eutectic in some superalloys powder, which promotes the formation of hafnium oxide. This encourages the formation of prior particle boundary (PPB) precipitates during HIPping, which decreases the bonding strength between powder particles during HIPping and thus becomes the crack initiation and growth sites under loading. Hence, this study aims at dissolving hafnium rich γ–γ′ eutectic in RR1000 superalloy powder and eliminating the PPB precipitates after HIPping by heat treating the powder prior HIPping. As-received powder was heat treated at 900, 1000, 1100, and 1200°C for 2 h, and their microstructure was characterized before the application of pressure for its consolidation. From the outcome of the study, 1200°C was found to be the optimum heat treatment temperature where hafnium rich γ–γ′ eutectic dissolved and where prior particle boundary (PPB) precipitates were eliminated during HIPping for the RR1000 superalloy powder studied.
Vegetable Oils as Quenchants for Steels: Residual Stresses and Dimensional Changes
Authors: Civera C. , Rivolta B. , Simencio-Otero R. L. , Lúcio J. G. , Totten G. E. , Canale L. C. F.
Published: September 2014

The development of non-toxic, biodegradable vegetable oils as alternatives to petroleum derived quenchants and their influence on residual stresses and dimensional changes of AISI 4140 and AISI H13 modified C-ring steel test specimens is discussed. The C-ring test specimens were quenched in 6 different vegetable oil blends based on soybean oil and the results were compared to 2 different commercially available petroleum oil quenchants. Residual stresses were determined by X-ray analysis on cylindrical test specimens after quenching. Some measurements were also performed using the hole-drilling method to confirm the results obtained using X-ray analysis.
Small Specimen Data from a High Temperature HFIR Irradiation Experiment
Authors: Burchell Tim , McDuffee Joel , Thoms Ken
Published: September 2014

The HTV capsule is a High Flux Isotope Reactor (HFIR) target-rod capsule designed to operate at very high temperatures. The graphite containing section of the capsule (in core) is approximately 18 in. (457.2 mm) long and is separated into eight temperature zones. The specimen diameters within each zone are set to achieve the desired gas gap and hence design temperature (900, 1200, or 1500°C). The capsule has five zones containing 0.400 in. (10.16 mm) diameter specimens, two zones containing 0.350 in. (8.89 mm) diameter specimens and one zone containing 0.300 in. (7.62 mm) diameter specimens. The zones have been distributed within the experiment to optimize the gamma heating from the HFIR core as well as minimize the axial heat flow in the capsule. Consequently, there are two 900°C zones, three 1200°C zones, and three 1500°C zones within the HTV capsule. Each zone contains nine specimens 0.210 ± 0.002 in. (5.334 mm) in length. The capsule will be irradiated to a peak dose of 3.17 displacements per atom. The HTV specimens include samples of the following graphite grades: SGL Carbon’s NBG-17 and NBG-18, GrafTech’s PCEA, Toyo Tanso’s IG-110, Mersen’s 2114, and the reference grade H-451 (SGL Carbon). As part of the pre-irradiation program, the specimens were characterized using ASTM Standards C559 for bulk density, and ASTM C769 for approximate Young’s modulus from the sonic velocity. The probe frequency used for the determination of time of flight of the ultrasonic signal was 2.25 MHz. Marked volume (specimen diameter) effects were noted for both bulk density (increased with increasing specimen volume or diameter) and dynamic Young’s modulus (decreased with increasing specimen volume or diameter). These trends are extended by adding the property versus diameter data for unirradiated AGC-1 creep specimens (nominally 12.5 mm-diameter by 25.4 mm-length). The relatively large reduction in dynamic Young’s modulus was surprising given the trend for increasing density with increasing volume. The graphite-filler particle size was noted to be influential in the volume dependency data, with finer grained graphites showing the least specimen volume/diameter effect. Here the volume dependency trends are discussed in terms of the graphite’s filler-particle size and texture.
Molecularizing Chicago—1945–1965
Authors: Sloan Phillip R.
Published: September 2014

This paper examines the history of biophysics at the University of Chicago, with a specific focus on the history of the Institute for Radiobiology and Biophysics (IRB), established at the university in 1945 as a continuation of the Manhattan Project. Discussed herein is how biophysical research developed at Chicago, and how the IRB formed the locus for early work in photosynthesis, phage genetics, and nucleic acid chemistry. The discontinuation of this institution in 1954 did not, however, terminate such work, but led to its dispersal into other entities within the university. Therefore the dramatic institutionalization of “molecular biology” and the creation of the Department of Biophysics under the presidency of George Beadle that commenced in the early 1960s relied upon a preexisting tradition rather than creating a new molecular phase in Chicago biology. This paper also shows that the interest in topics such as phage genetics and nucleic acid chemistry were continuous developments at Chicago from the early 1950s and did not represent a late interest in these topics.
Two-year clinical evaluation of resinous restorative systems in non-carious cervical lesions
Authors: Santiago Sérgio Lima , Passos Vanara Florêncio , Vieira Alessandra Helen Magacho , Navarro Maria Fidela de Lima , Lauris José Roberto Pereira , Franco Eduardo Batista
Published: September 2014

This controlled clinical trial evaluated the 2-year clinical performance of a one-bottle etch-and-rinse adhesive and resin composite system (Excite/Tetric Ceram) compared to a resin-modified glass ionomer cement (RMGIC) (Vitremer/3M) in non-carious cervical lesions. Seventy cervical restorations (35 resin composite - RC- restorations and 35 RMGIC restorations) were placed by a single operator in 30 patients under rubber dam isolation without mechanical preparation. All restorations were evaluated blindly by 2 independent examiners using the modified USPHS criteria at baseline, and after 6, 12 and 24 months. Data were analyzed statistically by Fisher's exact and McNemar tests. After 2 years, 59 out of 70 restorations were evaluated. As much as 78.8% retention rate was recorded for RC restorations, while 100% retention was obtained for RMGIC restorations. Fisher's exact test showed significant differences (p=0.011) for retention. However, there were no significant differences for marginal integrity, marginal discoloration, anatomic form and secondary caries between the RC and RMGIC restorations. The McNemar test detected significant differences for Excite/TC between baseline and the 2-year recall for retention (p=0.02), marginal integrity (p=0.002) and anatomic form (p=0.04). Therefore, the one-bottle etch-and-rinse bonding system/resin composite showed an inferior clinical performance compared to the RMGIC.
Intelligent label – a new way to support food waste reduction
Authors: Rossaint Sonja , Kreyenschmidt Judith
Published: September 2014

Approximately 20% of meat and meat products is wasted. One important reason for the waste of perishable meat products is incorrect handling, such as improper storage or missing information about the real quality status. In order to decrease the amount of food waste, the application of intelligent packaging solutions such as time–temperature indicators is discussed with increasing frequency. In this paper, the impact of intelligent label application in a typical poultry supply chain, with special regard to sustainable food production, is demonstrated. The results show that the additional information provided by a time–temperature indicator leads to a reduction of food waste. The amount of food waste (12%) and the waste reduction due to the implementation of the time–temperature indicator (35%) is defined based on expert interviews. The overall amount of waste and waste reduction is calculated for each step of a defined German poultry supply chain. The impact of the waste reduction on selected environmental parameters is also calculated. Furthermore a system is developed to calculate the cost and benefits for intelligent label application for each step in the chain.
An Innovative Approach to Reverse Production Decline in Brown Fields
Authors: Guehria Fawzi M. , Collaku Alban
Published: September 2014

It is known that the vast majority of oil and gas fields in the world are on decline; generally in these fields, the high uncertainties stemming from geological complexities and operational risks do not leave much room for risky and costly interventions or ill-planned reactions to issues such as loss of well productivity, water and/or gas breakthoughs. These fields rather need a much elaborated approach to enhance oil or gas throughput while reducing risks and maintaining minimal operations cost. For that, it is best to opt for a strategy, which articulates around day-to-day management through usage of expertise, adapted technology and long-term planning. This requires an integrated approach where the engineering diagnosis/conceptual/ analysis part is intimately tied to the execution/evaluation and other operational and cost constraints.

This work shows through a case study the value of integration in brown field projects. It highlights the fact that by collaborating as a joint project team, excellent results are achieved in field management but also tangible value is gained by unlocking the true reservoir potential that can be achieved through an optimum use of technology and data integration workflows when applied in junction with operations tasks.
Improved Oil Recovery Potential by Using Emulsion Flooding
Authors: Demikhova I. I. , Likhanova N. V. , Moctezuma A. E. , Hernandez Perez J. R. , Olivares-Xometl O. , Lijanova I. V.
Published: September 2014

The present paper deals with emulsion flooding laboratory experiments in porous media, which were performed to investigate the potential use of emulsions as IOR technologies in brownfields of the Gulf of Mexico. Until now, the method of chemical emulsion injections free of siloxanes or fluorinated compounds to promote the hydrophobization of sandstone rocks to reconfigure the phase flow paths, water and oil, generating changes in the flow patterns after the injection of water in order to improve and increase the oil recovery has not been described in the literature.

Oil-in-water emulsions were used along with a sand pack and a sandstone core. The flooding tests were carried out with Ottawa sand and Berea sandstones, respectively. The diameter size of the 90 % dispersed phase (D90), which was represented by a hydrophobic chemical compound, was lower than 5 μm and characterized by laser diffraction; the continuous phase was water. Initially, the oil was displaced by water injection. At the end of this step, the oil production fell to zero; all the oil inside the pore space was immobile. An emulsion slug was then injected, followed by another cycle of water injection. During this process, the additional oil recovery was higher than 15 %.

An oil-in-water emulsion based on a hydrophobic compound blocked a small, water-full pore and additionally, changed the pore surface wettability from water-wet to oil-wet, which modifies the preferential water routes, increasing the volumetric sweep, changing the residual oil saturation and finally, increasing the oil recovery factor.

The results suggest the possibility of using this novel technology in IOR projects for mature oil fields that feature medium gravity (20 °API) and produce high water cut. In addition, this technology is not affected by water salinity and temperature.
Technologies Based on Hydrocarbon-Base Surfactant Compositions for Improved Efficiency of Oil Recovery
Authors: Sobanova O. B. , Lebedev N. A.
Published: September 2014

The scientists of JSC NIIneftepromchim have been developing the reagents and methods for improved efficiency of oil recovery using the hydrocarbon-base surfactant compositions (HBSC) for a number of years.

Application of the compositions containing surfactants of different types instead of the single surfactant changes the properties of these systems over a wide range and adapts the compositions for different geological and physical conditions of the oil fields.

A number of technologies based on HBSC was developed and successfully applied for enhanced oil recovery. The conducted work proves good prospects for application of these technologies for improved efficiency of oil recovery in the mature oil fields with high water cut of well production.
Geomechanic Model Reconstruction for the Choice of Development Strategy
Authors: Mityaev M. , Belozerov B. , Lukin S.
Published: September 2014

Nowadays there is tendency to involve hard-to-recover reserves. As the consequence it starts to involve low permeable reservoirs with high number of permeable intervals in section. These technics demand to practice the new methods of oil development such as horizontal well drilling with multi hydraulic fracturing.

Relatively high coast of such wells poses much higher requirements on cumulative production of every single well. Further concerning of the problem makes efficient sister of pressure maintenance implementation. On of the most encountered issue is the constant water breakthrough as a consequence of pressure close to formation breakdown pressure, low reservoir properties and the last but not least non-correct organized development system (e.g. horizontal wells orientation in case of stress anisotropy).

According to the hydrodynamics modeling data estimation, the maximum of recovery factor for the oil reservoirs achieved by the elongation the development system in one direction with maximum stress line. Therefore the purpose is the maximum recovery factor achievement by the elongation of hydraulic fractures with the rows of injection wells and rows of production wells, making system with piston-like displacement.

One of the main claims of such systems is clear understanding the maximum stress directions in a every particular formation. In the paper the issue is complicated by strike-slip faults and as a consequence strains. Such a strain is hard to be found by seismic data and the determination of the main stress direction in the case of fields with late stage of development becomes hard. This paper concerns the method of stress direction recovery with the help of 3D seismic and early performed hydraulic fracturing.
Risk Evaluation of Investment Decision During Low Oil Prices
Authors: Kolbikov Sergey , Kolbikova Ekaterina , Sholudko Alexander
Published: September 2014

Profitability of investment projects for oil fields development is dropping drastically in the period of low oil prices especially if production drilling is in progress (so called "green fields"). Decision that is usually made in order to keep a positive annual profit during such period often leads to drilling suspension as the most capital-intensive process. Influence assessment of the investment project indicators in terms of fluctuating oil prices and long period of time has not been extended yet.

The analysis of factors affecting the oil price and its trend building are brought in the paper. The evaluation of the investment project on the production drilling in the low oil price period is performed in two scenarios: high oil price volatility trend and current price. It was shown that in order to avoid loses in short term period the company and the government miss the benefits in the long term perspective. The case study is based on the 2008 economic crises. The methodology of project estimation by using high oil price volatility trend within its range of uncertainty is suggested in the paper.
Application of Mathematical Optimization Techniques for Well Pattern Selection
Authors: Khasanov M. M. , Babin V. M. , Melchaeva O. U. , Ushmaev O. S. , Ciaurri D. Echeverria , Semenikhin A. S.
Published: September 2014

The paper describes an approach to selection of horizontal well placement. Given a field dynamic model we use advanced optimization techniques to select horizontal well length, well placement, well control that improve the field economics (as measured by the net present value, NPV) and increase field recoveries. Well-known problems of using optimization algorithms for field development are: (1) big number of variables, simplest well description assumes 5 variables: position, lateral length, orientation, bottom-hole pressure; (2) computational complexity of hydrodynamic simulation. In order to deal with high dimensionality and computation complexity we propose multi-layer approach. First, we decompose optimal well placement and control task of high dimension into a number of optimization problems of lower dimension: selection of optimal well pattern, local well placement optimization, selection of well control. That allows significantly decrease a number of simulation runs. Second, we use chain of simulators and dynamic models (from analytic models to fine-scale hydrodynamic model). The optimal solution for well placement obtained on simple model is used as input (baseline) solution for more complicated models. Thus we reduce number of complicated model runs.

The proposed approach was implemented in experimental software that automatically optimize horizontal well placement and well control using Eclipse dynamic model. We use this software to optimize FDP of a JSC "Gazprom neft" greenfield. The optimization resulted in significant increase of the field NPV and increase of expected recovery factor: 14% and 1.7% respectively. We estimate that optimization techniques contribution is 9% of NPV and 0.4% of RF.