bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spiraled Boreholes: An Expression of 3D Directional Instability of Drilling Systems
Authors: Marck Julien , Detournay Emmanuel 
Published: March 2015

Abstract
The occurrence of borehole spiraling is predicted by analyzing the delay differential equations that govern the propagation of a borehole. These evolution equations for borehole inclination and azimuth are obtained by considering the following three model components: (i) a bit/rock interaction law that relates the force and moment acting on the bit to its penetration into the rock; (ii) kinematic relationships that describe the local borehole geometry from the bit penetration; and (iii) a beam model for the bottom-hole assembly (BHA) that can be used to express the force and moment at the bit from the external loads applied on the BHA and the geometrical constraints arising from the stabilizers conforming to the borehole geometry.
The analytical nature of borehole propagation equations makes it possible to conduct a stability analysis in terms of a key dimensionless group that controls the directional stability of the drilling system. This group depends on the downhole weight on bit (WOB), on properties of the BHA, on the bluntness of the bit, and on parameters characterizing its response. The directional stability of a particular drilling system can be assessed by comparing the magnitude of this group with a critical value that depends only on the BHA configuration and on the bit walk. If this dimensionless group, which depends on the actual drilling conditions, is less than the bifurcation value, the system is deemed to be directionally unstable, and borehole spiraling is likely. Stability curves for an ideal BHA with two stabilizers are shown to depend on the bit walk. An application to a field example is discussed. Borehole simulations, based on solving the equations of propagation, also are presented to illustrate that, for unstable systems, the model reproduces spiraled boreholes with a pitch, comparable to what is observed in the field.
Overcoming Barriers to Adoption of Drilling Automation: Moving Towards Automated Well Manufacturing
Authors: Ambrus Adrian , Pournazari Parham , Ashok Pradeepkumar , Shor Roman , van Oort Eric 
Published: March 2015

Abstract
There has been a growing interest in automated drilling in the recent decade, motivated primarily by increased well construction efficiency, enhanced safety and well quality requirements. Many drilling tasks have been successfully automated and pilot technologies have been deployed, but broader adoption has remained slow. This can be attributed to some key factors. First, no two wells or rigs are the same. So the concept of “developing one algorithm applicable to all scenarios” is difficult except in the simplest of cases where only a limited set of tightly integrated sensors and actuators are involved. Secondly, full automation requires cohesive data and information integration between multiple stakeholders: the operator, the service provider, the drilling contractor and the equipment manufacturer. No efficient mathematical construct has been adopted for integrating data / information from these different stakeholders. Thirdly, any drilling automation task requires the full buy-in of the drilling crew, which is often difficult when these algorithms are presented as black-box solutions and it is unclear how to bring the rig to a safe condition when automation fails.
A mathematical construct, and the methodology / architecture is presented that would enable one to combine information and data from multiple sources in a meaningful way and the rapid development of intuitive control algorithms that can be easily understood without advanced degrees or training is demonstrated. The algorithm development process is purposefully simplified, allowing for well engineers to easily develop their own control strategies while enabling rig- and site-specific customization. Additionally, the visual nature of the methodology enables easy monitoring by the rig crew for troubleshooting purposes. Automation scenarios are presented for tripping and Managed Pressure Drilling operations that demonstrate the ease of use. Multiple control strategies are developed for each task, and compared against criteria that include easy comprehension of the algorithm and optimality. This automation approach can help reduce some of the current barriers to broad scale adoption of automation.
Expert Real-Time Drilling Performance Prevents Twist-offs and Reduces Bit Damage in the Permian Basin
Authors: Hood James , Taylor Richard , Morris Paul , Riley Brian , Plouzek Damian , Wilson John , Metz Mike , Alam Rashid 
Published: March 2015

Abstract
Sudden growth of the Permian's Delaware Basin, exploiting multiple unconventional targets, has increased the number of drilling rigs in the area to well over 550. This rapid expansion of drilling rigs has diluted the pool of experienced drillers and operators in the region, which in turn has caused numerous drilling optimization problems such as poor penetration rates and accelerated wear on drillstring components. To enhance the learning curve and address these drilling practices, a number of operators have requested real-time downhole dynamics and mechanics information to improve drilling performance.
Previously, a dedicated ‘down-hole drilling dynamics service’ was successfully deployed to the Permian for recording the down-hole drilling dynamics environment in memory mode. This service confirmed strong dynamic events occurring, and subsequently allowed adjustments to be made to the drill string components and operational parameters. However, the memory only approach meant a delayed improvement cycle, never reaching its full optimization potential or technical capabilities.
Providing a ‘real-time down-hole drilling dynamics service’ delivered immediate improvements to performance through real-time drilling parameter adjustments, as well as enabling optimum bit and bottom hole assembly selection for subsequent wells. The continuous performance improvement loop highlighted the best drilling practices, permitting the development and implementation of refined drilling procedures, and further enhanced performance and safety.
This paper addresses drilling dynamics challenges encountered and overcame while drilling vertical sections in six wells (on four rigs) by one operator in the Permian Basin. The data and examples presented in this paper provide an understanding of the benefits of managing drilling parameters in real-time and express the best drilling practices. Using a ‘real-time down-hole drilling dynamics service’ reduced overall operator costs by an average of 24% per well when compared to previous wells. Additionally, real-time down-hole weight on bit functionality offered an increased safety feature over a conventional drilling system, while the use of close-to-bit rotational inclination provided enhanced vertical control versus the standard survey system of a conventional straight-hole drilling assembly.
Resistance of ‘Zhongmai 155’ Wheat to Powdery Mildew: Effectiveness and Detection of the Resistance Gene
Authors: Sun Huigai , Song Wei , Sun Yanling , Chen Xinmin , Liu Jianjun , Zou Jingwei , Wang Xiaoming , Zhou Yinfu , Lin Xiaohu , Li Hongjie 
Published: March 2015

ABSTRACTPowdery mildew, caused by the biotrophic parasitic fungusBlumeria graminisf. sp.tritici(Bgt), is a prevalent disease in many wheat (Triticum aestivumL.)–producing regions throughout the world. To reduce yield losses and avoid environmental pollution caused by fungicide application, growing resistant cultivars is the preferred means for managing wheat powdery mildew. ‘Zhongmai 155’, a commercial winter wheat cultivar released in 2012, was resistant to 92 of the 115Bgtisolates originating from northern China. Using segregating F2and F2:3populations derived from Zhongmai 155 × ‘Han 4564’ cross, genetic analysis indicated that a single dominant resistance gene, tentatively designatedPmZ155, was responsible for the resistance of Zhongmai 155 to theBgtisolate E09. The gene was subsequently localized on chromosome 5DS on the basis of the results of molecular marker analysis. The flanking markersSCAR203 and Xcfd8are linked to genePmZ155at genetic distances of 0.3 and 4.9 cM, respectively, and were physically mapped to the deletion bin 5DS‐1‐0‐0.63; therefore,PmZ155is located in this region of chromosome 5DS and shares the same molecular markers asPm2. However, Zhongmai 155 differed from Ulka/8*Cc (CI 14118), which carries genePm2on chromosome 5DS, in its reactions to 26 of 111 commonly tested isolates, of which 18 isolates were avirulent on Zhongmai 155 but virulent on Ulka/8*Cc, while 8 isolates were virulent on Zhongmai 155 but avirulent on Ulka/8*Cc. Zhongmai 155 also differed from ‘Tabasco’ (carryingPm48on chromosome 5DS) in its reaction to 14 of 62 isolates. On the basis of its chromosome position, close linkage to the molecular markersXcfd8andSCAR203, but different responses to an array ofBgtisolates, it appears thatPmZ155is most likely an allele of locusPm2.
Genetic and Heterosis Analyses using Hayman's Six‐Generation Model for Grain Yield and Yield Components in Maize
Authors: Chen H.M. , Zhang Y.D. , Jiang F.Y. , Huang Y.X. , Yao W.H. , Chen X.H. , Kang M.S. , Fan X.M. 
Published: March 2015

ABSTRACTThis study aimed to (i) estimate additive (a), dominance (d), aa, ad, and dd genetic variances and effects; (ii) investigate the differences for five genetic variances or effects among crosses between a maize (Zea mays L.) line from the Suwan‐1 heterotic group and five inbred lines from other groups; and (iii) develop a theory to explain the results from Hayman's model and low‐, mid‐, and high‐parent heterosis. Hayman's model was used to evaluate the genetic effects in five six‐generation sets between the Suwan‐1 cross with five lines from other groups. The magnitude of variance was consistent among all crosses for grain yield (GY) and ear length (EL) but different for ear diameter (ED), row number per ear (RE), kernel number per row (KR), and 100‐kernel weight (KW). The a, d, aa, ad, and dd effects were similar for EL among crosses between lines from different groups, indicating that the effects for EL could be used to differentiate Reid and non‐Reid heterotic groups. We postulated a ‘linked coexpressed genes’ (LCG) model to (i) explain why a, d, aa, ad, and dd variances and effects might be different when a common line is crossed with other lines and (ii) serve as an improved model explaining heterosis. The LCG model explains what dominance–overdominance theories can explain and explains what dominance–overdominance models do not. For example, it can explain why an inbred line cannot perform like a hybrid and why an F2 population for a quantitative trait has a normal distribution.
Grass and Legume Effects on Nutritive Value of Complex Forage Mixtures
Authors: Brink G.E. , Sanderson M.A. , Casler M.D. 
Published: March 2015

ABSTRACTDry matter productivity of complex forage mixtures is typically influenced by a dominant species, but nutritive value may be a function of multiple components. Two experiments were conducted in Pennsylvania and Wisconsin during 2 yr. Each experiment consisted of 15 mixtures and monocultures of orchardgrass (Dactylis glomerata L.), quackgrass (Elymus repens (L.) Gould), alfalfa (Medicago sativa L.), and white clover (Trifolium repens L.), or of meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], reed canarygrass (Phalaris arundinacea L.), red clover (Trifolium pratense L.), and kura clover (Trifolium ambiguum M. Bieb.). Vegetative‐stage mixtures and monocultures were harvested five times each year. Botanical composition was used to calculate the additive effect of each species, or the expected change in nutritive value associated with a change in proportion of a species in the mixture from 0 to 100%. Nutritive value differences among mixtures attributed to abundance of sown species were evident the first year, but except for monocultures, had largely disappeared in the second year. White clover and meadow fescue had a positive additive effect on forage digestibility (range of 36 to 80 g kg−1), but alfalfa and reed canarygrass had no additive effect on digestibility. Legumes generally had a negative additive effect (range of −179 to −81 g kg−1) and grasses a positive effect (range of 81 to 166 g kg−1) on forage neutral detergent fiber concentration. The results suggest that species with high nutritive value relative to other species within the same functional group have a disproportionate effect on nutritive value of complex mixtures.
Phenomorphological Characterization of Vegetable Soybean Germplasm Lines for Commercial Production
Authors: Williams Martin M. 
Published: March 2015

ABSTRACTGrowing demand for vegetable soybean [Glycine max (L.) Merr.] has renewed interest in producing the crop in the United States, a significant importer of vegetable soybean despite being the world's largest producer and exporter of grain‐type soybean. Field studies were conducted over 3 yr to(i) compare phenomorphological traits of vegetable and grain‐type soybean and (ii) identify candidate lines for vegetable soybean production in the North Central United States, the nation's leading soybean‐producing region. A total of 136 vegetable soybean entries from 22 sources were compared to 14 grain‐type cultivars representing a range of maturity groups. Germination and emergence of vegetable soybean were poorer than grain‐type entries. Seedling growth traits and rate of phenological development were higher in vegetable soybean. However, by the time of crop harvest (i.e., R6 growth stage), vegetable soybean produced shorter, smaller plants than grain‐type soybean. Seed mass accounted for some of the variation in emergence and seedling traits. Filtering entry responses by criteria essential to viable commercial production, including a sensory evaluation, 12 entries from eight seed sources were identified as the most promising candidate lines for use in the North Central United States. By comparing vegetable soybean responses to grain‐type soybean, this work puts into perspective the agronomic performance of vegetable soybean germplasm available to growers in the United States and points to specific areas of future research and crop development.
Relations Between Subclinical Disease Markers and Type 2 Diabetes, Metabolic Syndrome, and Incident Cardiovascular Disease: The Jackson Heart Study
Authors: Xanthakis Vanessa , Sung Jung Hye , Samdarshi Tandaw E. , Hill Alethea N. , Musani Solomon K. , Sims Mario , Ghraibeh Kamel A. , Liebson Philip R. , Taylor Herman A. , Vasan Ramachandran S. , Fox Ervin R. 
Published: March 2015

OBJECTIVE
The presence of subclinical disease measures has been directly associated with the development of cardiovascular disease (CVD) in whites. African Americans (AAs) in the U.S. are at higher risk of CVD compared with non-Hispanic whites; however, data on the prevalence of subclinical disease measures in AAs and their association to CVD remain unclear and may explain the higher CVD risk in this group.

RESEARCH DESIGN AND METHODS
We evaluated 4,416 participants attending the first examination of the Jackson Heart Study (mean age 54 years; 64% women) with available subclinical disease measures.

RESULTS
There were 1,155 participants (26%) with subclinical disease, defined as the presence of one or more of the following: peripheral arterial disease, left ventricular hypertrophy, microalbuminuria, high coronary artery calcium (CAC) score, and low left ventricular ejection fraction. In cross-sectional analyses using multivariable-adjusted logistic regression, participants with metabolic syndrome (MetS) or diabetes (DM) had higher odds of subclinical disease compared with those without MetS and DM (odds ratios 1.55 [95% CI 1.30–1.85] and 2.86 [95% CI 2.32–3.53], respectively). Furthermore, the presence of a high CAC score and left ventricular hypertrophy were directly associated with the incidence of CVD (265 events) in multivariable-adjusted Cox proportional hazards regression models (P &lt; 0.05). In prospective analyses, having MetS or DM significantly increased the hazard of incident CVD, independent of the presence of subclinical disease (P &lt; 0.001).

CONCLUSIONS
In our community-based sample of AAs, we observed a moderately high prevalence of subclinical disease, which in turn translated into a greater risk of CVD, especially in people with MetS and DM.
The morphology of tense and aspect in Nama, a Papuan language of southern New Guinea
Authors: Siegel Jeff 
Published: March 2015

AbstractThis paper describes the complex tense and aspect morphology in Nama, a previously undocumented Papuan language of southern New Guinea. Tense/aspect suffixes followed by agent/actor referencing suffixes occur in combination with one of two sets of patient referencing prefixes. Most of the tense/aspect suffixes mark two possible tenses, and the choice of a prefix from a particular set determines the appropriate interpretation. The distinction between imperfective and perfective aspect is central to the Nama tense/aspect system, and the forms of the perfectivity markers depend on the number category of the grammatical arguments: dual versus non-dual, which encompasses both singular and plural (i.e. more than two). At the same time, the agent/actor suffixes and patient referencing prefixes generally index two different number categories: singular versus non-singular. Each of the two basic aspects has three different tenses, with some other aspectual distinctions occurring only with singular arguments. A combination of imperfective and perfective marking is also used.
Modeling Alterations in Sinonasal Physiology after Skull Base Surgery
Authors: Frank-Ito Dennis O. , Sajisevi Mirabelle , Solares C. Arturo , Jang David W. 
Published: March 2015

Background Endonasal endoscopic skull base surgery (EESBS) often requires significant alterations in intranasal anatomy. For example, posterior septectomy (PS) with middle turbinate resection (MTR) is frequently performed to provide access to large sellar and clival tumors. However, little is known about the alterations that occur in sinonasal physiology. This study was designed to assess changes in sinonasal physiology after virtually performed endoscopic skull base surgery. Methods Three-dimensional models of the sinonasal passage were created from computed tomography scans in three subjects with varying anatomy: no SD (SD), right anterior SD, and left anterior SD, respectively. Four additional surgery types were performed virtually on each model: endoscopic transsphenoidal approach (ETSA) with small (1 cm) PS (smPS), ETSA with complete (2 cm) PS, ETSA with smPS and right MTR, and ETSA with complete PS and right MTR. Computational fluid dynamics (CFD) simulations were performed on the 3 presurgery and 12 virtual surgery models to assess changes from surgery types. Results Increased nasal airflow corresponded to amount of tissue removed. Effects of MTR on unilateral airflow allocation were unchanged in subject with no SD, worsened in leftward SD, and reversed in rightward SD. Severity of airflow and mucosal wall interactions trended with amount of tissue removed. MTR hindered flow interactions with the olfactory mucosa in subjects with SD. Conclusion CFD simulations on virtual surgery models are able to reasonably detect changes in airflow patterns in the computer-generated nasal models. In addition, each patient's unique anatomy influences the magnitude and direction of these changes after virtual EESBS. Once future studies can reliably correlate CFD parameters with patient symptoms, CFD will be a useful clinical tool in surgical planning and maximizing patient outcomes.
Development of Taiwan Smell Identification Test: A Quick Office-Based Smell Screening Test for Taiwanese
Authors: Hsu Ning-I , Lai Jen-Tsung , Shen Ping-Hung 
Published: March 2015

Background Objective smell tests not only identify levels of smelling ability but also provide information on changes in olfaction after treatment. Odor identification is strongly socially and culturally dependent; therefore, the odorants used in a smell identification test should be familiar to the test population. We developed this smell test for Taiwanese populations with two aims: the test odors should be familiar to Taiwanese and the test should be easily and quickly administered in a busy clinic. Methods Additives that are familiar to Taiwanese people were selected for this smell identification test. Subsequently, the test was validated with the traditional Chinese version of the University of Pennsylvania Smell Identification Test (TC-UPSIT). Finally, this Taiwan Smell Identification Test (TWSIT) was implemented in daily clinical use, and cut-off points of “normosmia,” “hyposmia,” and “anosmia” were established. Results A total of 1000 subjects were included in the market survey to identify commonly recognized odors. Eight odorants with identification rate greater than 95% were selected. The TWSIT is an array of multiple-choice questions to select the odor. In addition, patient also reported the strength of the odor. The full score was 48. Thirty-seven patients simultaneously received both TWSIT and TC-UPSIT, and the correlation was high (r = 0.874). Based on the testing results of an additional 187 subjects, we concluded that scores of 47–48, 15–44, and 2–12 corresponded to normosmia, hyposmia, and anosmia, respectively. Patients with scores falling in the gaps require retesting at a later time. Conclusion The TWSIT is a quick, office-based, and useful odor identification tool for Taiwanese. The experience of developing a culturally specific olfaction test like the TWSIT can be applied in different countries and cultures.
Outcomes of intraventricular hemorrhage and posthemorrhagic hydrocephalus in a population-based cohort of very preterm infants born to residents of Nova Scotia from 1993 to 2010
Authors: Radic Julia A. E. , Vincer Michael , McNeely P. Daniel 
Published: March 2015

OBJECT
Intraventicular hemorrhage (IVH) is a common complication of preterm birth, and the prognosis of IVH is incompletely characterized. The objective of this study was to describe the outcomes of IVH in a population-based cohort with minimal selection bias.

METHODS
All very preterm (≥ 30 completed weeks) patients born in the province of Nova Scotia were included in a comprehensive database. This database was screened for infants born to residents of Nova Scotia from January 1, 1993, to December 31, 2010. Among very preterm infants successfully resuscitated at birth, the numbers of infants who died, were disabled, developed cerebral palsy, developed hydrocephalus, were blind, were deaf, or had cognitive/language scores assessed were analyzed by IVH grade. The relative risk of each outcome was calculated (relative to the risk for infants without IVH).

RESULTS
Grades 2, 3, and 4 IVH were significantly associated with an increased overall mortality, primarily in the neonatal period, and the risk increased with increasing grade of IVH. Grade 4 IVH was significantly associated with an increased risk of disability (RR 2.00, p < 0.001), and the disability appeared to be primarily due to cerebral palsy (RR 6.07, p < 0.001) and cognitive impairment (difference in mean MDI scores between Grade 4 IVH and no IVH: −19.7, p < 0.001). No infants with Grade 1 or 2 IVH developed hydrocephalus, and hydrocephalus and CSF shunting were not associated with poorer outcomes when controlling for IVH grade.

CONCLUSIONS
Grades 1 and 2 IVH have much better outcomes than Grades 3 or 4, including a 0% risk of hydrocephalus in the Grade 1 and 2 IVH cohort. Given the low risk of selection bias, the results of this study may be helpful in discussing prognosis with families of very preterm infants diagnosed with IVH.