bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Spectral Noise Logging and High Precision Temperature (SNL-HPT) To Identify Hydrocarbon and Water Bearing Zones in Naturally Fractured Reservoirs (NFR) – A Case Study of Potwar Region
Authors: Zakir Mufaddal Murtaza , Hussain Saddam , Qazi Shoukat Elahi , Ali Shahzad , Muhammad Danish , Haleemuddin H. M. , Hassan Mohsin , Iqbal Muneez
Published: November 2016

Uncontrolled water production in naturally fractured tight carbonate reservoirs with low porosities is a serious problem that confronts Petroleum engineers in Potwar region of Pakistan. The potential of hydrocarbons in these reservoir rocks is masked by the undesirable high water cut. Spectral Noise Logging, High-Precision Temperature Logging in combination with conventional production logging can yield valuable information on gas, oil and water flow profile and behind casing communication in wells.

This paper demonstrates how the (SNL-HPT) diagnostic tool was employed in a well producing from a naturally fractured carbonate reservoir to analyze flow stream to identify hydrocarbon and water flowing intervals and cross flows behind casing. Spectral Noise Logging (SNL) can provide information on reservoir flow units behind one or multiple barriers, which is beyond the spinner capability of PLT. The acoustic noise caused by moving fluid is the result of internal friction and normally audible in highly turbulent flows. Its spectrum and volume is strongly dependent on the fluid type, pressure, temperature and flow rate.

Well-A was drilled and perforated in Sakessar formation of Eocene age. The well flowed at low oil rate and high water cut (98%) despite being at an up dip location compared to a near-by producing well (Well-B) with less water cut from the same zone. To identify the problem, diagnostic logs (SNL-HPT) were run in combination in Well-A to ascertain the perforation's flow profile and flow behind casing if any.

The diagnostic logs interpretation indicated that the bottom most perforation sets were producing the major volume of fluid and no cross flow behind casing was detected. Based on the analyses of logs, the bottom perforation sets were plugged with calcium carbonate chips capped by cement plug. After water shut off job, the well was flowed and reduced water cut along with decline in gross fluid was observed indicating that the top perforations may have not been acidized. A small acid job was subsequently carried out to stimulate the upper perforation which improved oil rates and the water cut reduced to 60%. Later PLT was also conducted in order to acquire post water shut-off profile and verify SNL-HPT results.
A Paradigm Shift: Higher Recovery from Water-drive Gas Reservoirs Producing through Wells having Bigger Size Completion
Authors: Ahmad Fazeel , Zahoor Muhammad Khurram
Published: November 2016

Developing prolific gas reservoirs in an optimized manner has always been a challenge. The situation becomes more complicated when production tubing size is to be optimized for wells completed in water-drive gas reservoirs. In such reservoir, after breakthrough it is normally preferred to reduce the completion size for prolonged well life under natural flow. However, in this study, analysis has been accomplished on a gas well completed in a prolific reservoir under water drive mechanism, which showed better performance with bigger completion size in both early and later (after water breakthrough) stages of the well completed in a high productivity reservoirs. This has a positive impact on completion strategy of such gas reservoirs. This study negates the usual concept of reducing the tubing size to sustain gas production after water breakthrough in prolific water drive gas reservoirs. Further, this work also highlights the benefits of using bigger completion size in gas wells under natural flow completed in prolific homogeneous reservoir. This analysis could benefit the petroleum community in the similar cases, in future.
The Quest for Productivity Steering
Authors: Haq Shahid A. , Denichou Jean M. , Okoroafor Rita , Zhou Wentao
Published: November 2016

Over the past forty years, steering a horizontal well has evolved from geometric to structural to facies type and now productivity steering. This paper is aimed to summarize the evolution of wellbore steering and the impact of logging-while-drilling on well and reservoir performance.

The quest for productivity drilling began in the late 1980s with the first generation of logging-whiledrilling (LWD) technology that provided directional and formation-evaluation measurements and basic data insurance in vertical and deviated wells. The primary applications were stratigraphic and structural correlation and rudimentary formation evaluation. A shift in LWD technology in the 1990s increased the focus on exploitation of smaller, tighter, and harder-to-reach reservoirs. This second phase saw the introduction of azimuthal measurements, borehole images, instrumented steerable motors, and forwardmodeling programs for well placement through geosteering. Well architectures became more challenging as well construction evolved from geometrical designs to wells steered by geological information. In the 21st century, geosteering entered its third phase; structural steering with deep-reading LWD resistivity measurements and high-resolution imaging. This allowed operators to reposition in real-time horizontal and high-angle wellbore trajectories in anticipation of structural changes ahead of the bit.

Two recent developments since 2010 have taken geosteering to the next phase of productivity steering. The first one is reservoir mapping while drilling. It uses continuous bed boundary logs from deep azimuthal electromagnetic measurements. The second one is fluid mapping while drilling. It incorporates discrete/station measurements of reservoir rock and fluid properties from formation testing while drilling along with advanced mud gas logs. These developments have made it possible to estimate the productivity index (PI) of openhole section, in near real time, during reservoir drilling process.

The productivity index while drilling estimate can therefore be used for drilling decisions as well as completion decisions and to evaluate the effect of trajectory undulations on well productivity while drilling. Real Time Productivity Steering (RTPS) is hence no longer a myth but a reality now.
New Methodology to Quantify Productivity of Vertical Wells in Naturally Fractured Solution Gas Drive Reservoirs with Dual Porosity and Dual Permeability
Authors: Tariq Zeeshan , Alnuaim Sami , Abdulraheem Abdulazeez , Khan Mohammad Rasheed
Published: November 2016

Forecasting the performance of individual wells is of great importance to oil companies for continuous field production optimization and cost per barrel reduction. Well Performance is measured by evaluating the Inflow Performance & Outflow Performance Relationships (IPR & OPR). For that the need to use the correct IPR for subjected reservoir is very essential.

Since many decades, Vogel IPR equation has been used comprehensively for evaluating the productivity of vertical wells in saturated gas drive reservoirs. Vogel's model successfully evaluates IPR for single porosity solution gas drive in homogenous reservoirs. However, the applicability of Vogel's IPR for naturally fractured dual porosity-dual permeability reservoirs is questionable; hence this challenge is addressed by the industry only numerically. Due to composite fluid flow behavior between fracture and matrix system in a dual porosity-dual permeability reservoir, there is a pressing need for a new, practical and simple IPR model that takes into account the consideration of fracture parameters.

This study investigates the effects of reservoir complex fluid flow behavior on IPR curves for vertical wells drilled in naturally fractured oil saturated reservoirs resulting in the development of an IPR curve for such conditions. A base case simulation model is developed with typical reservoir, fluid and rock properties using black oil model. Using a set of points relating oil production rates to flowing bottom-hole pressures, the dimensionless IPR curves are generated. Fluid and reservoir properties were varied between two porous and permeable media such as Inter-porosity flow co-efficient, storativity ratio, oil gravity, reservoir thickness and bubble point pressure. Inter-porosity flow coefficient and fracture storativity ratio were found to have a significant impact on dimensionless IPR curves. Finally, an attempt is made to converge the results into one simple model using non-linear regression technique in order to get a new empirical IPR correlation for vertical well producing from naturally fractured oil reservoirs.

A small and acceptable average absolute error of less than 2% was found with the new proposed empirical IPR model, while comparing the existing published correlations on the same data gives more than 15% error. The developed IPR correlation is accurate enough and can serve as a handy tool for the production engineers to forecast the productivity of wells drilled in a naturally fractured dual porosity-dual permeability saturated oil reservoirs.
Development Strategy for a Low BTU Gas Discovery with Effective Design of Interference Test & Utilization of Limited Pressure & Production Data for GIIP Estimates by Material Balance P/Z Technique - A Case Study
Authors: Anjum Muhammad Ghufran , Khan Muhammad Noman , Rizwan Muhammad , Khan Muhammad Wahjuddin
Published: November 2016

Material balance P/Z method is widely applicable concept in reservoir engineering to estimate GIIP in volumetric dry gas reservoirs. The application of conventional P/Z method is based on constant pore volume assumption and reliable production of GIIP & PVT data. In newly drilled prospects there is always huge uncertainty in dynamic GIIP due to unavailability of significant production & pressure data [1] and uncertainty of drive mechanism. However, production tests (Reservoir Limit Test, Interference Test, etc.) for longer duration are usually designed to acquire reliable production and average reservoir pressure data to have indicative estimates of GIIP and drive mechanism in order to have development & appraisal program with more certainty.

Low BTU gas with more than 50% inert in the gas cannot be allowed to be injected in the buyer's network. Commercial development of such discoveries for power generation needs firm commitments of gas supply which is based on GIIP estimates which usually have uncertainty due to lack of production and pressure data at the time of discovery.

In this paper we will give a brief insight on the techniques to acquire reliable production data with longer production tests & their limitations, Pros & Cons of conventional P/Z approach for GIIP estimation in the newly drilled prospect. The case study will show how the limited pressure & production data may also be utilized with caution to have minimum GIIP estimates using P/Z method especially in case of overpressure reservoir where drive mechanism is most likely volumetric by designing simplified numerical modeling approach without conducting longer production tests. However, this technique has limitations in case of poroelastic nature of reservoir.
The Potential of Strip Tillage and Rowcovers for Organic Cucurbit Production
Authors: Lilley Jason M. , Sánchez Elsa S.
Published: November 2016

Plasticulture systems, the use of polyethylene mulch on raised beds with drip irrigation, are commonly used for the production of many cucurbit (Cucurbitaceae) crops. Although the use of plasticulture systems has many benefits, disadvantages include plastic disposal issues and costs and the intensive tillage required for installation. Strip tillage systems have been shown to decrease soil erosion, increase soil moisture retention, and increase soil microbial communities. Spunbonded polyethylene rowcover use has been shown to decrease early season striped cucumber beetle (Acalymma vittatum) and spotted cucumber beetle (Diabrotica undecimpunctata) populations and the incidence of bacterial wilt (Erwinia tracheiphila) while increasing yields. Plasticulture and strip tillage systems were compared with and without rowcovers at The Pennsylvania State University’s Russell E. Larson Research and Education Center in Rock Springs, PA. Two separate organically managed experiments were conducted, one being on ‘Lioness’ summer squash (SS; Cucurbita pepo), the other on ‘Athena’ muskmelon (MM; Cucumis melo). Both two-season experiments occurred during the 2013 and 2014 growing seasons. Yields, soil nitrate levels, soil and air temperatures, striped cucumber beetle populations, and incidence of bacterial wilt were measured. Plants grown in the strip tillage system generally had lower yields than in the plasticulture system in both years. Yield reductions observed in the strip tillage system in both years of the muskmelon experiment and in the first year of the summer squash experiment were beyond acceptable levels. The need for specialized tillage equipment, delayed planting, and high weed pressure were all obstacles to the successful use of strip tillage in these experiments. Rowcovers resulted in larger plants; however, yields were comparable to not using rowcovers within the strip tillage and plasticulture systems. There was low incidence of bacterial wilt in both years of the experiments despite observed striped cucumber beetle populations above the set threshold throughout all experiments.
Effects of Cover Crops, Compost, and Vermicompost on Strawberry Yields and Nitrogen Availability in North Carolina
Authors: Beck John E. , Schroeder-Moreno Michelle S. , Fernandez Gina E. , Grossman Julie M. , Creamer Nancy G.
Published: November 2016

Summer cover crop rotations, compost, and vermicompost additions can be important strategies for transition to organic production that can provide various benefits to crop yields, nitrogen (N) availability, and overall soil health, yet are underused in strawberry (Fragaria ×ananassa) production in North Carolina. This study was aimed at evaluating six summer cover crop treatments including pearl millet (Pennisetum glaucum), soybean (Glycine max), cowpea (Vigna unguiculata), pearl millet/soybean combination, pearl millet/cowpea combination, and a no cover crop control, with and without vermicompost additions for their effects on strawberry growth, yields, nutrient uptake, weeds, and soil inorganic nitrate-nitrogen and ammonium-nitrogen in a 2-year field experiment. Compost was additionally applied before seeding cover crops and preplant N fertilizer was reduced by 67% to account for organic N additions. Although all cover crops (with compost) increased soil N levels during strawberry growth compared with the no cover crop treatment, cover crops did not impact strawberry yields in the first year of the study. In the 2nd year, pearl millet cover crop treatments reduced total and marketable strawberry yields, and soybean treatments reduced marketable strawberry yields when compared with the no cover crop treatment, whereas vermicompost additions increased strawberry biomass and yields. Results from this study suggest that vermicompost additions can be important sustainable soil management strategies for transitional and certified organic strawberry production. Summer cover crops integrated with composts can provide considerable soil N, reducing fertilizer needs, but have variable responses on strawberry depending on the specific cover crop species or combination. Moreover, these practices are suitable for both organic and conventional strawberry growers and will benefit from longer-term studies that assess these practices individually and in combination and other benefits in addition to yields.
Evaluating the Implementation of Video Web Conferencing in Delaware Master Gardener Training
Authors: Barton Emily A. , Barton Susan S. , Ilvento Thomas
Published: November 2016

In the 2015 Delaware (DE) Master Gardener training, instructors synchronously delivered content to two trainee cohorts (Cohorts A and B) who met at three locations (Sites 1, 2, and 3) via video web conferencing (VWC). This reduced instructor delivery and travel time but warranted close examination of trainee learning outcomes and experiences. To evaluate the pilot implementation of remote delivery, trainees [number of trainees (N) = 30] answered two open-ended application questions after 11 instructional sessions. One cohort received instruction face-to-face, while the other cohort synchronously received instruction via remote delivery [number of participants in cohort 1 (n1) = 17; number of participants in cohort 2 (n2) = 13]; each cohort was remote for about half of the sessions. The overall average face-to-face score assessing session content mastery was higher than the overall average remote score by 0.1, a 5% difference given the possible scores range of 0 to 2.0. When we grouped sessions by remote delivery site, delivery mode only significantly predicted average session scores for those sessions delivered remotely to Site 2 and not those delivered remotely to either Site 1 or Site 3. When we considered each session individually, delivery mode significantly predicted session scores for 2 of the 11 sessions, both broadcast remotely to trainees at Site 2, where the bandwidth was 10% of those at Sites 1 and 3. We suggest the VWC system performed particularly poorly for these sessions due to limited bandwidth. Posttraining survey results suggest the VWC system did not function well enough to approximate face-to-face instruction. The overall educational rating of the training was significantly higher than the media naturalness rating suggesting poor technical functionality did not substantially undermine trainees’ perception of the education they received. This study indicates remote delivery is a viable strategy for improving the efficiency of training programs if it is consistently implemented with the appropriate technical infrastructure.
Nitrate removal from natural water by coupling adsorption and Donnan dialysis
Authors: Turki Thouraya , Ben Amor Mohamed
Published: November 2016

A hybrid adsorption/Donnan dialysis (DD) process for nitrate removal using PUROLITE A520E resin as an adsorbent was investigated in this work. PUROLITE resin was introduced into the DD process due to its good selectivity adsorption for nitrate and widespread availability. This study was conducted in order to benefit from each process, and it was an original and new combination. The retention efficiency of nitrate was discussed by considering the factors of adsorbent mass, nature of the receiver electrolyte and flow rate. The coupling was a solution to improve the resin mass and the amount of nitrate removed. The coupling was successfully performed, with a nitrate removal capacity of about 7 mg/g.
FIXED COMBINATION OF ANTIDIABETIC DRUGS IN THE TREATMENT OF TYPE 2 DIABETES: FROM THEORY TO PRACTIC
Authors: Karachentsev Yu. I. , Kazakov A. V. , Romanova I. P. , Chernyavskaya I. V. , Kravchun N. A.
Published: November 2016

In the review it was presented data about using of antidiabetic drugs with a fixed combination of their components. The authors paid attention of effectiveness appointment of this drugs in certain clinical situations. It was shown the results of own research taking into account the long-term results.
FEATURES OF CHANGES IN CIRCADIAN RHYTHM OF CIRCULATING LEVELS OF INSULIN AND GLUCOSE IN THE METABOLIC SYNDROME INDUCED EXPERIMENTAL HYPOPINEALISM
Authors: Mishchenko T. V. , Gladkih A. I. , Poltorak V. V. , Bondarenko L. O.
Published: November 2016

In the experimental study on young adult male rabbits it was found leveling of circadian rhythm in insulin concentration and violation of circadian pattern of glucose (inversion, which is replaced by leveling) in the dynamics of the formation of metabolic syndrome, which develops in the hypopinealism induced by long-term exposure to low-light in the dark. Change in the circadian rhythm of secretion of insulin, glucose, and hyperinsulinemia that result of chronic disturbance of natural light/dark cycle, are the basis of the manifestation of the metabolic syndrome in hypopinealism.
RELATIONSHIP ADIPOCYTOKINES WITH ACTIVITY IMMUNE SYSTEM IN TYPE 2 DIABETES MELLITUS COMBINED WITH NONALCOHOLIC FATTY LIVER DISEASE (literature review and own data)
Authors: Chernyavskay I. V. , Dorosh E. G. , Polozova L. G. , Cherniaieva A. A. , Dunayeva I. P. , Alexeeva I. I. , Kozar V. V. , Kravchun N. A.
Published: November 2016

In the review it was presented the literature data devoted to the study of the activity of the immune system, the levels of adipocytokines in patients with type 2 diabetes mellitus combined with non-alcoholic fatty liver disease. It was shown the results of own research anti- and pro-oxidant status and cytokine profile in patients with type 2 diabetes mellitus combined with non-alcoholic fatty liver disease. It was found an increase in pro-oxidant status indicators, levels of leptin and IL-6 combined with type 2 diabetes, obesity and NAFLD in comparison with patients with type 2 diabetes without NAFLD and obesity.
Interlaboratory Variability in Plasma Creatinine Measurement and the Relation with Estimated Glomerular Filtration Rate and Chronic Kidney Disease Diagnosis
Authors: Lee Elizabeth , Collier Christine P. , White Christine A.
Published: November 2016

Background and objectives

The tracing of creatinine (Cr) reference materials to isotope dilution mass spectrometry–assigned values was implemented worldwide to reduce interlaboratory variability and improve assay accuracy. The aims of this study were to examine the current extent of interlaboratory variability and its effect on eGFR.

Design, setting, participants, & measurements

Leftover plasma from 2–3 consecutive days was obtained from 53 intensive care unit patients with a range of kidney functions. Individual patient samples were pooled and split and sent to 12 different laboratories for Cr measurement. For each patient, the mean Cr and Chronic Kidney Disease Epidemiology Collaboration eGFR (eGFR-EPI), assuming a 65-year-old nonblack woman, were determined. Interlaboratory variability was assessed by the range and SD of Cr and eGFR-EPI. This was repeated after stratifying by assay type and by the median Cr of 1.36 mg/dl. For patients whose eGFR-EPI range included 60 ml/min per 1.73 m2, the percentage of laboratories with eGFR-EPI<60 ml/min per 1.73 m2 was determined.

Results

The mean±SD of the Cr and eGFR-EPI ranges were 0.20±0.09 mg/dl and 14±9 ml/min per 1.73 m2 for Cr<1.36 mg/dl. Jaffe Cr results were an average 0.1 mg/dl (Cr≥1.36 mg/dl) and 0.05 mg/dl (Cr<1.36 mg/dl) higher than enzymatic results (P<0.001 for both). Ten patients had an eGFR-EPI range that included 60 ml/min per 1.73 m2. Their median eGFR-EPI range was 15 ml/min per 1.73 m2. There was significant discordance in the diagnosis of CKD (eGFR-EPI<60 ml/min per 1.73 m2), with laboratories using Jaffe Cr methods making the diagnosis more frequently than those using enzymatic Cr methods (60% versus 39%).

Conclusions

Significant interlaboratory variability in Cr measurement still exists. Jaffe assays yield higher Cr values than enzymatic assays, leading to lower eGFR-EPIs and more frequent CKD diagnoses. Further improvements in assay performance are required to standardize patient CKD diagnosis and to facilitate longitudinal Cr monitoring across laboratories.
The effects of symmetry-breaking functions on the Ermakov-Pinney equation
Authors: Morris R.M. , Leach P.G.L.
Published: November 2016

The Ermakov-Pinney Equation, x?? + ?2x = h2/x3, has a varied provenance which
we briefly delineate. We introduce time-dependent functions in place of the ?2
and h2. The former has no effect upon the algebra of the Lie point symmetries
of the equation. The latter destroys the sl(2,R) symmetry and a single
symmetry persists only when there is a specific relationship between the two
time-dependent functions introduced. We calculate the form of the
corresponding autonomous equation for these cases.
Visualization and Quantification of Browning Using a Ucp1-2A-Luciferase Knock-in Mouse Model
Authors: Mao Liufeng , Nie Baoming , Nie Tao , Hui Xiaoyan , Gao Xuefei , Lin Xiaoliang , Liu Xin , Xu Yong , Tang Xiaofeng , Yuan Ran , Li Kuai , Li Peng , Ding Ke , Wang Yu , Xu Aimin , Fei Jian , Han Weiping , Liu Pentao , Madsen Lise , Kristiansen Karsten , Zhou Zhiguang , Ding Sheng , Wu Donghai
Published: November 2016

Both mammals and adult humans possess classic brown adipocytes and beige adipocytes, and the amount and activity of these adipocytes are considered key factors in combating obesity and its associated metabolic diseases. Uncoupling protein 1 (Ucp1) is the functional marker of both brown and beige adipocytes. To facilitate a reliable, easy, and sensitive measurement of Ucp1 expression both in vivo and in vitro, we generated a Ucp1-2A-luciferase knock-in mouse by deleting the stop codon for the mouse Ucp1 gene and replacing it with a 2A peptide. This peptide was followed by the luciferase coding sequence to recapitulate the expression of the Ucp1 gene at the transcriptional and translational levels. With this mouse, we discovered a cold-sensitive brown/beige adipose depot underneath the skin of the ears, which we named uBAT. Because of the sensitivity and high dynamic range of luciferase activity, the Ucp1-2A-luciferase mouse is useful for both in vitro quantitative determination and in vivo visualization of nonshivering thermogenesis. With the use of this model, we identified and characterized axitinib, an oral small-molecule tyrosine kinase inhibitor, as an effective browning agent.
Macrophage Proliferation Sustains Adipose Tissue Inflammation in Formerly Obese Mice
Authors: Zamarron Brian F. , Mergian Taleen A. , Cho Kae Won , Martinez-Santibanez Gabriel , Luan Danny , Singer Kanakadurga , DelProposto Jennifer L. , Geletka Lynn M. , Muir Lindsey A. , Lumeng Carey N.
Published: November 2016

Obesity causes dramatic proinflammatory changes in the adipose tissue immune environment, but relatively little is known regarding how this inflammation responds to weight loss (WL). To understand the mechanisms by which meta-inflammation resolves during WL, we examined adipose tissue leukocytes in mice after withdrawal of a high-fat diet. After 8 weeks of WL, mice achieved similar weights and glucose tolerance values as age-matched lean controls but showed abnormal insulin tolerance. Despite fat mass normalization, total and CD11c+ adipose tissue macrophage (ATM) content remained elevated in WL mice for up to 6 months and was associated with persistent fibrosis in adipose tissue. ATMs in formerly obese mice demonstrated a proinflammatory profile, including elevated expression of interferon-γ, tumor necrosis factor-α, and interleukin-1β. T-cell–deficient Rag1−/− mice showed a degree of ATM persistence similar to that in WT mice, but with reduced inflammatory gene expression. ATM proliferation was identified as the predominant mechanism by which ATMs are retained in adipose tissue with WL. Our study suggests that WL does not completely resolve obesity-induced ATM activation, which may contribute to the persistent adipose tissue damage and reduced insulin sensitivity observed in formerly obese mice.
Long-Term Clinical Outcomes and Factors That Predict Poor Prognosis in Athletes After a Diagnosis of Acute Spondylolysis: A Retrospective Review With Telephone Follow-up
Authors: Selhorst Mitchell , Fischer Anastasia , Graft Kristine , Ravindran Reno , Peters Eric , Rodenberg Richard , MacDonald James
Published: November 2016

Study Design

Retrospective review with telephone follow-up.

Background

Acute spondylolytic injuries have a dramatic impact on the young athlete. Excellent short-term clinical outcomes have been observed, but not enough is known about long-term clinical outcomes.

Objectives

(1) To report long-term clinical outcomes for patients diagnosed with acute spondylolysis, and (2) to assess the prognostic ability of retrospective variables for long-term outcomes.

Methods

Patients from 2010 through 2013 were retrospectively reviewed to identify patients and to obtain demographic, baseline, and short-term outcomes. Long-term follow-up data were collected by telephone from patients diagnosed with acute spondylolysis to assess recurrence rate of low back pain, perceived outcome, pain, and functional ability. Patients were categorized as having a good or poor long-term outcome based on these measures. Logistic regression analysis was performed to assess the prognostic ability of the retrospective variables for long-term outcomes 3.4 years (range, 1.5–5.6 years) after treatment.

Results

One hundred twenty-one (71.6%) patients completed the follow-up questionnaire (48 female; mean age at baseline, 14.4 years). At follow-up, 81 (66.9%) patients were able to maintain their same or a higher level of sport. Recurrence of significant symptoms was reported by 55 (45.5%) patients, with 41 (33.9%) requiring medical treatment. The final logistic regression model revealed that female sex, adverse reaction during care, and multilevel injury were significant predictors of poor long-term outcome (R2 = 0.22).

Conclusion

Although excellent short-term outcomes were noted, 42% of patients reported a poor outcome at long-term follow-up. Female sex, multilevel injury, and experiencing an adverse reaction during care were significant predictors of poor long-term clinical outcome for patients diagnosed with acute spondylolysis.

Level of Evidence

Prognosis, level 4. Registered January 15, 2015 at www.clinicaltrials.gov (NCT02332200). J Orthop Sports Phys Ther 2016;46(12):1029–1036. Epub 8 Nov 2016. doi:10.2519/jospt.2016.7028
Place of Birth and Concepts of Wellbeing
Authors: McCourt Christine , Rayment Juliet , Rance Susanna , Sandall Jane
Published: November 2016

Abstract

This article is based on analysis of a series of ethnographic case studies of midwifery units in England. Midwifery units1 are spaces that were developed to provide more home-like and less medically oriented care for birth that would support physiological processes of labour, women’s comfort and a positive experience of birth for women and their families. They are run by midwives, either on a hospital site alongside an obstetric unit (Alongside Midwifery Unit – AMU) or a freestanding unit away from an obstetric unit (Freestanding Midwifery Unit – FMU). Midwifery units have been designed and intended specifically as locations of wellbeing and although the meaning of the term is used very loosely in public discourse, this claim is supported by a large epidemiological study, which found that they provide safe care for babies while reducing use of medical interventions and with better health outcomes for the women. Our research indicated that midwifery units function as a protected space, one which uses domestic features as metaphors of home in order to promote a sense of wellbeing and to re-normalise concepts of birth, which had become inhabited by medical models and a preoccupation with risk. However, we argue that this protected space has a function for midwives as well as for birthing women. Midwifery units are intended to support midwives’ wellbeing following decades of professional struggles to maintain autonomy, midwife-led care2 and a professional identity founded on supporting normal, healthy birth. This development, which is focused on place of birth rather than other aspects of maternity care such as continuity, shows potential for restoring wellbeing on individual, professional and community levels, through improving rates of normal physiological birth and improving experiences of providing and receiving care. Nevertheless, this very focus also poses challenges for health service providers attempting to provide a ‘social model of care’ within an institutional context.

1The term midwifery unit was adopted by the Birthplace research programme in place of the more popular term ‘birth centre’ to avoid ambiguity. In a midwifery unit care is not only provided by mid-wives but is also managed by midwives and does not normally include use of obstetric instruments or interventions. If a woman planning birth in a mid-wifery unit develops obstetric complications, or decides she wishes to have a medical intervention such as epidural pain relief, she is transferred for care to an obstetric unit. Some units called birth centres are not managed by midwives in this way.

2Midwife-led care refers to care where the midwife, rather than an obstetrician or other professional is the lead professional, who takes responsibility for a woman’s maternity care through from pregnancy to postnatal. Following the Changing Childbirth report in 1993, this was re-established as the usual model for women classified as at low risk of pregnancy and birth complications.
A Procedure for Identification of Appropriate State Space and ARIMA Models Based on Time-Series Cross-Validation
Authors: Ramos Patrícia , Oliveira José
Published: November 2016

In this work, a cross-validation procedure is used to identify an appropriate Autoregressive Integrated Moving Average model and an appropriate state space model for a time series. A minimum size for the training set is specified. The procedure is based on one-step forecasts and uses different training sets, each containing one more observation than the previous one. All possible state space models and all ARIMA models where the orders are allowed to range reasonably are fitted considering raw data and log-transformed data with regular differencing (up to second order differences) and, if the time series is seasonal, seasonal differencing (up to first order differences). The value of root mean squared error for each model is calculated averaging the one-step forecasts obtained. The model which has the lowest root mean squared error value and passes the Ljung–Box test using all of the available data with a reasonable significance level is selected among all the ARIMA and state space models considered. The procedure is exemplified in this paper with a case study of retail sales of different categories of women’s footwear from a Portuguese retailer, and its accuracy is compared with three reliable forecasting approaches. The results show that our procedure consistently forecasts more accurately than the other approaches and the improvements in the accuracy are significant.
On Thermodynamics Problems in the Single-Phase-Lagging Heat Conduction Model
Authors: Li Shu-Nan , Cao Bing-Yang
Published: November 2016

Thermodynamics problems for the single-phase-lagging (SPL) model have not been much studied. In this paper, the violation of the second law of thermodynamics by the SPL model is studied from two perspectives, which are the negative entropy production rate and breaking equilibrium spontaneously. The methods for the SPL model to avoid the negative entropy production rate are proposed, which are extended irreversible thermodynamics and the thermal relaxation time. Modifying the entropy production rate positive or zero is not enough to avoid the violation of the second law of thermodynamics for the SPL model, because the SPL model could cause breaking equilibrium spontaneously in some special circumstances. As comparison, it is shown that Fourier’s law and the CV model cannot break equilibrium spontaneously by analyzing mathematical energy integral.
Fostering Creativity in the Classroom for High Ability Students: Context Does Matter
Authors: Tan Liang , Lee Shu , Ponnusamy Letchmi , Koh Elizabeth , Tan Keith
Published: November 2016

Researchers have argued for the importance of the classroom context in developing students’ creative potential. However, the emphasis on a performative learning culture in the classroom does not favour creativity. Thus, how creative potential can be realised as one of the educational goals in the classrooms remains a key question. This study measured creativity across three secondary schools using the Wallach-Kogan Creative Thinking Test (WKCT). A total of 283 students enrolled in the Express programme and 290 students enrolled in the Integrated Programme (IP) volunteered in the study. The same cohort of students took the 38-item WKCT twice; once at the beginning of Secondary One and then at the end of Secondary Three. Four aspects of creativity, namely fluency, flexibility, unusualness, and uniqueness, were investigated. Our analyses showed that (i) IP students showed a greater increase in scores over time when compared to Express students; (ii) when Programme and PSLE (Primary School Leaving Examination) were used to predict creativity scores in a multiple regression, the predictive power of Programme increased from Secondary 1 to Secondary 3 while that of PSLE decreased; and (iii) flexibility scores were more resistant to change than fluency scores. These findings suggest that the classroom context matters and that the removal of high-stakes examination can provide room for the development of creative potential.
Power Quality Disturbances Feature Selection and Recognition Using Optimal Multi-Resolution Fast S-Transform and CART Algorithm
Authors: Huang Nantian , Peng Hua , Cai Guowei , Chen Jikai
Published: November 2016

In order to improve the recognition accuracy and efficiency of power quality disturbances (PQD) in microgrids, a novel PQD feature selection and recognition method based on optimal multi-resolution fast S-transform (OMFST) and classification and regression tree (CART) algorithm is proposed. Firstly, OMFST is carried out according to the frequency domain characteristic of disturbance signal, and 67 features are extracted by time-frequency analysis to construct the original feature set. Subsequently, the optimal feature subset is determined by Gini importance and sorted according to an embedded feature selection method based on the Gini index. Finally, one standard error rule subtree evaluation methods were applied for cost complexity pruning. After pruning, the optimal decision tree (ODT) is obtained for PQD classification. The experiments show that the new method can effectively improve the classification efficiency and accuracy with feature selection step. Simultaneously, the ODT can be constructed automatically according to the ability of feature classification. In different noise environments, the classification accuracy of the new method is higher than the method based on probabilistic neural network, extreme learning machine, and support vector machine.
New Requirements of the Voltage/VAR Function for Smart Inverter in Distributed Generation Control
Authors: Kim Yun-Su , Kim Gyeong-Hun , Lee Jae-Duck , Cho Changhee
Published: November 2016

International Electronical Committee (IEC) 61850-90-7 is a part of the IEC 61850 series which specifies the advanced functions and object models for power converter based Distributed Energy Resources (DERs). One of its functions, the Voltage/VAR (V/V) control function, is used to enhance the stability and the reliability of the voltage in the distribution system. The conventional V/V function acts mainly for flattening the voltage profile as for a basic grid support function. Currently, other objectives such as the minimization of line loss and the operational costs reduction are coming into the spotlight. In order to attain these objectives, the V/V function and hence the DER units shall actively respond to the change of distribution system conditions. In this paper, the modification of V/V function and new requirements are proposed. To derive new requirements of V/V function, loss minimization is applied to a particle swarm optimization (PSO) algorithm where the condition of voltage constraint is considered not to deteriorate the voltage stability of the distribution system.
Forecasting Electricity Market Risk Using Empirical Mode Decomposition (EMD)—Based Multiscale Methodology
Authors: He Kaijian , Wang Hongqian , Du Jiangze , Zou Yingchao
Published: November 2016

The electricity market has experienced an increasing level of deregulation and reform over the years. There is an increasing level of electricity price fluctuation, uncertainty, and risk exposure in the marketplace. Traditional risk measurement models based on the homogeneous and efficient market assumption no longer suffice, facing the increasing level of accuracy and reliability requirements. In this paper, we propose a new Empirical Mode Decomposition (EMD)-based Value at Risk (VaR) model to estimate the downside risk measure in the electricity market. The proposed model investigates and models the inherent multiscale market risk structure. The EMD model is introduced to decompose the electricity time series into several Intrinsic Mode Functions (IMF) with distinct multiscale characteristics. The Exponential Weighted Moving Average (EWMA) model is used to model the individual risk factors across different scales. Experimental results using different models in the Australian electricity markets show that EMD-EWMA models based on Student’s t distribution achieves the best performance, and outperforms the benchmark EWMA model significantly in terms of model reliability and predictive accuracy.
Analysis of Power Quality Signals Using an Adaptive Time-Frequency Distribution
Authors: Khan Nabeel , Baig Faisal , Nawaz Syed , Ur Rehman Naveed , Sharma Shree
Published: November 2016

Spikes frequently occur in power quality (PQ) disturbance signals due to various causes such as switching of the inductive loads and the energization of the capacitor bank. Such signals are difficult to analyze using existing time-frequency (TF) methods as these signals have two orthogonal directions in a TF plane. To address this issue, this paper proposes an adaptive TF distribution (TFD) for the analysis of PQ signals. In the proposed adaptive method, the smoothing kernel’s direction is locally adapted based on the direction of energy in the joint TF domain, and hence an improved TF resolution can be obtained. Furthermore, the performance of the proposed adaptive technique in analyzing electrical PQ is thoroughly studied for both synthetic and real world electrical power signals with the help of extensive simulations. The simulation results (specially for empirical data) indicate that the adaptive TFD method achieves high energy concentration in the TF domain for signals composed of tones and spikes. Moreover, the local adaptation of the smoothing kernel in the adaptive TFD enables the extraction of TF signature of spikes from TF images, which further helps in measuring the energy of spikes in a given signal. This new measure can be used to both detect the spikes as well as to quantify the extent of distortion caused by the spikes in a given signal.
Steric Clash in the SET Domain of Histone Methyltransferase NSD1 as a Cause of Sotos Syndrome and Its Genetic Heterogeneity in a Brazilian Cohort
Authors: Ha Kyungsoo , Anand Priya , Lee Jennifer , Jones Julie , Kim Chong , Bertola Debora , Labonne Jonathan , Layman Lawrence , Wenzel Wolfgang , Kim Hyung-Goo
Published: November 2016

Most histone methyltransferases (HMTase) harbor a predicted Su(var)3–9, Enhancer-of-zeste, Trithorax (SET) domain, which transfers a methyl group to a lysine residue in their substrates. Mutations of the SET domains were reported to cause intellectual disability syndromes such as Sotos, Weaver, or Kabuki syndromes. Sotos syndrome is an overgrowth syndrome with intellectual disability caused by haploinsufficiency of the nuclear receptor binding SET domain protein 1 (NSD1) gene, an HMTase at 5q35.2–35.3. Here, we analyzed NSD1 in 34 Brazilian Sotos patients and identified three novel and eight known mutations. Using protein modeling and bioinformatic approaches, we evaluated the effects of one novel (I2007F) and 21 previously reported missense mutations in the SET domain. For the I2007F mutation, we observed conformational change and loss of structural stability in Molecular Dynamics (MD) simulations which may lead to loss-of-function of the SET domain. For six mutations near the ligand-binding site we observed in simulations steric clashes with neighboring side chains near the substrate S-Adenosyl methionine (SAM) binding site, which may disrupt the enzymatic activity of NSD1. These results point to a structural mechanism underlying the pathology of the NSD1 missense mutations in the SET domain in Sotos syndrome. NSD1 mutations were identified in only 32% of the Brazilian Sotos patients in our study cohort suggesting other genes (including unknown disease genes) underlie the molecular etiology for the majority of these patients. Our studies also found NSD1 expression to be profound in human fetal brain and cerebellum, accounting for prenatal onset and hypoplasia of cerebellar vermis seen in Sotos syndrome.
Secular Trends in Growth and Nutritional Outcomes of Children under Five Years Old in Xiamen, China
Authors: Chen Jing , Chen Wei , Zeng Guozhang , Li Guimei
Published: November 2016

The purpose of this study was to examine secular changes in growth and nutritional outcomes of Chinese urban children under five years old, in 2009, 2012, and 2015. Cluster random sampling methods were used to select children under five years old in Xiamen, one of five special economic zones in China. Subjects (N = 71,229) under five years old (39,413 boys, 31,816 girls) were examined at three different times (22,576 in 2009, 24,816 in 2012, and 23,837 in 2015). Significant differences in the boys’ height and weight (p < 0.05) were found across the three time points; subjects in the 2015 sample were the heaviest and tallest, and they had the highest BMI (2009 < 2015; 2012 < 2015). Among the girls, those in the 2015 sample were similar to the boys (2009 < 2012; 2012 < 2015). In general, similar patterns were observed when mean values were analyzed by age. An increasing trend was found in the prevalence of overweight and obesity and a decreasing trend for stunting, underweight, and wasting. The results revealed that the burden of childhood under- and over-nutrition might constitute a public health concern in modern China.
Patterns of Smoking and Snus Use in Sweden: Implications for Public Health
Authors: Ramström Lars , Borland Ron , Wikmans Tom
Published: November 2016

There has been concern that the availability of alternative less harmful forms of nicotine might inhibit smoking cessation and/or encourage those who would not otherwise have smoked to do so. The plausibility of such effects can be best assessed by looking at population trends in use of smoking in relation to alternatives. This paper looks at the relationships between snus use and smoking in Sweden. Analyses are based on a data set for the period January 2003 to February 2011 from a long-term study covering nationally representative samples of the Swedish population aged 18–79, with a total study population of 60,675 individuals. Questionnaires made it possible to identify detailed tobacco use categories and use trajectories. The results showed that uptake of snus use is much more common in males than females. Those who began daily tobacco use using snus were much less likely to subsequently take up smoking than those who had not, both among males (17.6% vs. 45.9%), and females (8.2% vs. 40.2%). Further, among those who started using snus after starting as smokers, 76.3% of men and 71.6% of women had stopped smoking completely, including 31.5% of the men and 28.6% of the women who had quit all forms of tobacco. Indeed, those who were primary snus users were also more likely to have quit altogether than those who only ever smoked. Snus was also reported as the most common smoking cessation aid among men and yielded higher success rates than nicotine replacement therapy and other alternatives. As conclusions, snus has both contributed to decreasing initiation of smoking and, when used subsequent to smoking, appears to facilitate smoking cessation. All these effects suggest that the availability and use of snus has been a major factor behind Sweden’s record-low prevalence of smoking and the lowest level of tobacco-related mortality among men in Europe.