bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Simulation of Solidification of Colloids Inside a Differentially Heated Cavity
Authors: EL Hasadi Yousef M. F. , Khodadadi J. M.
Published: November 2014

Development of the solid–liquid interface, distribution of the particle concentration field, as well as the development of thermosolutal convection during solidification of colloidal suspensions in a differentially heated cavity are investigated. The numerical model is based on the one-fluid mixture approach combined with the single-domain enthalpy porosity model for phase change, and it is implemented in fluent software package. The linear dependence of the liquidus and solidus temperatures with the concentration of the nanoparticles was assumed. A colloidal suspension consisting of water and copper or alumina nanoparticles were considered. In the current investigation, the nanoparticle size selected was 5 and 2 nm. The suspension was solidified unidirectionally inside a square differentially heated cavity that was cooled from the left side. It was found that the solid–liquid interface changed its morphology from a planar shape to a dendritic one as the solidification process proceeds in time, due to the constitutional supercooling that resulted from the increased concentration of particles at the solid–liquid interface rejected from the crystalline phase. Initially, the flow consisted of two vortices rotating in opposite directions. However, at later times, only one counter clockwise rotating cell survived. Changing the material of the particle to alumina resulted in crystallized phase with a higher concentration of particles. If it is compared to that of the solid phase resulted from freezing the copper–water colloidal suspension. Decreasing the segregation coefficient destabilizes the solid–liquid interface and increases the intensity of the convection cell with respect to that of the case of no particle rejection. At slow freezing rates, the resulting crystal phase consisted of lower particle content compared to the case of higher freezing rate.
The Effects of Entrainment on Pore Shape in Keyhole Mode Welding
Authors: Wei P. S. , Chao T. C.
Published: November 2014

This study theoretically investigates the effects of the entrainment accompanying mass, momentum, and energy transport on pore size during high power density laser and electron beam welding processes. The physics of macroporosity formation is not well understood, even though macroporosity often occurs and limits the widespread industrial application of keyhole mode welding. This work is an extension of a previous work dealing with collapses of keyholes induced by high intensity beam drilling. In order to determine the pore shape, this study, however, introduces the equations of state at the times when the keyhole is about to be enclosed and when the temperature drops to melting temperature. The gas pressure required at the time when keyhole collapses is determined by calculating the compressible flow of the two-phase, vapor–liquid dispersion in a vertical keyhole with varying cross sections, paying particular attention to the transition between annular and slug flows. It is found that the pore size increases as entrainment fluxes decrease in the lower and upper regions of the keyhole containing a supersonic mixture. The pore size also increases with decreasing total energy of entrainment and an increasing axial velocity component ratio between entrainment and mixture through the core region. With a subsonic mixture in the keyhole, the final pore size increases with entrainment fluxes in the lower and upper regions. This work provides an exploratory and systematical investigation of pore size induced by entrainment accompanied by mass, momentum, and energy transport during keyhole mode welding.
Effects of Mn Content on the Deformation Behavior of Fe–Mn–Al–C TWIP Steels—A Computational Study
Authors: Wang Y. Y. , Sun X. , Wang Y. D. , Zbib H. M.
Published: November 2014

This paper presents a double-slip/double-twin polycrystal plasticity model using finite element solution to investigate the kinetics of deformation twinning of medium manganese (Mn) twinning-induced plasticity (TWIP) steels. Empirical equations are employed to estimate the stacking fault energy (SFE) of TWIP steels and the critical resolved shear stress (CRSS) for dislocation slip and deformation twinning, respectively. The results suggest that the evolution of twinning in Fe–xMn–1.4Al–0.6 C (x = 11.5, 13.5, 15.5, 17.5, and 19.5 mass%) TWIP steels, and its relation to the Mn content, can explain the effect of Mn on mechanical properties. By comparing the double-slip/double-twin model to a double-slip model, the predicted results essentially reveal that the interaction behavior between dislocation slip and deformation twinning can lead to an additional work hardening. Also, numerical simulations are carried out to study the influence of boundary conditions on deformation behavior and twin formation. The nucleation and growth of twinning are found to depend on internal properties (e.g., mismatch orientation of grains and stress redistribution) as well as on external constraints (e.g., the applied boundary conditions) of the material.
Multiscale Contribution of Bone Tissue Material Property Heterogeneity to Trabecular Bone Mechanical Behavior
Authors: Lloyd Ashley A. , Wang Zhen Xiang , Donnelly Eve
Published: November 2014

Heterogeneity of material properties is an important potential contributor to bone fracture resistance because of its putative contribution to toughness, but establishing the contribution of heterogeneity to fracture risk is still in an incipient stage. Experimental studies have demonstrated changes in distributions of compositional and nanomechanical properties with fragility fracture history, disease, and pharmacologic treatment. Computational studies have demonstrated that models with heterogeneous material properties predict apparent stiffness moderately better than homogeneous models and show greater energy dissipation. Collectively, these results suggest that microscale material heterogeneity affects not only microscale mechanics but also structural performance at larger length scales.
A Parametric Study on Laser Welding of Magnesium Alloy AZ31 by a Fiber Laser
Authors: Bailey Neil S. , Tan Wenda , Shin Yung C.
Published: November 2014

Laser welding of wrought magnesium alloy has been investigated through experimentation and simulation. Laser butt welds and laser lap welds were performed on 2.0 mm thick magnesium alloy AZ31 plates using a 1 kW fiber laser and shielded with argon gas. The effects of laser power and welding speed on weld geometry and microstructure were investigated. Tensile tests were performed to verify weld quality. Through experimentation, a novel processing map was created, which gives the ranges of operating parameters of laser power and welding speed that resulted in viable, defect-free welds. Numerical simulations were performed to predict the weld pool geometry and keyhole stability, and resultant microstructures are shown to be in good agreement with experimental results.
Dynamic Analysis of Active Magnetic Bearing Rotor Dropping on Auto-eliminating Clearance Auxiliary Bearing Devices
Authors: Yu Chengtao , Jin Chaowu , Yu Xudong , Xu Longxiang
Published: November 2014

Auto-eliminating clearance auxiliary bearing devices (ACABD) can automatically eliminate the protective clearance between the ball bearing's outer race and the ACABD's supports, thus recenter the rotor when active magnetic bearing (AMB) system fails. This paper introduces the mechanical structure and working principles of the ACABD. When the rotor drops, numerical and experimental studies on the transient responses of the rotor and the ACABD's supports are also conducted as follows. First, we propose an equivalent clearance circle method to establish dynamic models of rotor dropping on the ACABD. Based on these models, the rotor dropping simulations are carried out to investigate the modes of lubrication and the ACABD's support shape's influences on the performance and execution time of clearance elimination. Second, various AMB rotor dropping tests are performed on our experimental setup with different ACABD supporting conditions. Indicated from the basically consistent simulation and experimental results, the correctness of the theoretical analysis and the successful operation of ACABD have been verified. Moreover, with the grease lubrication in the ball bearing and convex shape supports, the ACABD can eliminate the protective clearance within approximately 0.5 s upon the rotor drops and then sustain the rotor to operate stably around its original rotation center. Because of clearance elimination, the dramatic impact between the ball bearing and the supports is avoided and the impact forces among each part are effectively reduced. Meanwhile, the possibility of incurring full-clearance backward whirling motion is eliminated.
#Fight4UNCWSwimandDive: A Case Study of How College Athletes Used Twitter to Help Save Their Teams
Authors: Hull Kevin
Published: November 2014

This study explored how student-athletes at UNC-Wilmington (UNCW) used Twitter to help save their swimming and diving teams from being eliminated. Both a series of interviews and a content analysis of 1,775 tweets by 25 athletes were conducted. The results suggest that athletes and advocates can use Twitter to raise awareness about their cause. The UNCW athletes’ goal to demonstrate community support by alerting as many people as possible through social media was achieved through tweeting consistently, becoming opinion leaders in the two-step flow of information, and using weak ties to get followers of other accounts to rally behind their cause. Limitations and directions for future research are also discussed.
Men Competing, Men Watching: Exploring Watching-Pattern Contingencies in Sports
Authors: Apostolou Menelaos , Frantzides Nicholas , Pavlidou Andromahi
Published: November 2014

People exhibit a considerable interest in attending and watching sports. This article attempts to explore whether this interest is asymmetrical, that is, whether individuals are more interested in watching members of one sex competing rather than the other. In particular, based on an evolutionary framework, 2 hypotheses are derived and tested. First, both sexes would be more interested in watching men than women competing, and, second, there would be an interaction between the spectators’ sex and the athletes’ sex. Evidence from a study of 19 different sports finds support for both hypotheses, with the interaction showing that men are more interested than women in watching male sports. The implications of these findings are further discussed.
Evaluation of Sports Nutrition Knowledge and Recommendations Among High School Coaches
Authors: Couture Steven , Lamarche Benoit , Morissette Eliane , Provencher Veronique , Valois Pierre , Goulet Claude , Drapeau Vicky
Published: November 2014

The objectives of this study were to evaluate high school coaches’ knowledge in sports nutrition and the nutritional practices they recommend to their athletes. Forty-seven high school coaches in “leanness” and “non-leanness” sports from the greater region of Quebec (women = 44.7%) completed a questionnaire on nutritional knowledge and practices. “Leanness sports” were defined as sports where leanness or/and low bodyweight were considered important (e.g., cheerleading, swimming and gymnastics), and “non-leanness sports” were defined as sports where these factors are less important (e.g., football). Participants obtained a total mean score of 68.4% for the nutrition knowledge part of the questionnaire. More specifically, less than 30% of the coaches could answer correctly some general nutrition questions regarding carbohydrates and lipids. No significant difference in nutrition knowledge was observed between coaches from “leanness” and “non-leanness” sports or between men and women. Respondents with a university education scored higher than the others (73.3% vs. 63.3%, p < .05). Coaches who participated in coaching certification also obtained better results than those without a coaching certification. The most popular source of information about nutrition used by coaches was the Internet at 55%. The two most popular nutrition practices that coaches recommended to improve athlete performance were hydration and consumption of protein-rich foods. Recommendation for nutritional supplements use was extremely rare and was suggested only by football coaches, a nonleanness sport. Findings from this study indicate that coaches need sports nutrition education and specific training.
Age Related Differences in the Validity of the OMNI Perceived Exertion Scale During Lifestyle Activities
Authors: Rice Kelly R. , Gammon Catherine , Pfieffer Karin , Trost Stewart
Published: November 2014

Purpose:

The OMNI perceived exertion scale was developed for children to report perceived effort while performing physical activity; however no studies have formally examined age-related differences in validity. This study evaluated the validity of the OMNI-RPE in 4 age groups performing a range of lifestyle activities.

Methods:

206 participants were stratified into four age groups: 6-8 years (n = 42), 9-10 years (n = 46), 11-12 years (n = 47), and 13-15 years (n = 71). Heart rate and VO2 were measured during 11 activity trials ranging in intensity from sedentary to vigorous. After each trial, participants reported effort from the OMNI walk/run scale. Concurrent validity was assessed by calculating within-subject correlations between OMNI ratings and the two physiological indices.

Results:

The average correlation between OMNI ratings and VO2 was 0.67, 0.77, 0.85, and 0.87 for the 6-8, 9-10, 11-12 and 13-15 y age groups, respectively.

Conclusion:

The OMNI RPE scale demonstrated fair to good evidence of validity across a range of lifestyle activities among 6- to 15-year-old children. The validity of the scale appears to be developmentally related with RPE reports closely reflecting physiological responses among children older than 8 years.
The UP4FUN Intervention Effect on Breaking Up Sedentary Time in 10- to 12-Year-Old Belgian Children: The ENERGY Project
Authors: Verloigne Maïté , Ridgers Nicola D. , Chinapaw Mai , Altenburg Teatske , Bere Elling , Berntsen Sveinung , Cardon Greet , Brug Johannes , De Bourdeaudhuij Ilse , Van Lippevelde Wendy , Maes Lea
Published: November 2014

There are currently no studies available reporting intervention effects on breaking up children’s sedentary time. This study examined the UP4FUN intervention effect on objectively measured number of breaks in sedentary time, number of sedentary bouts (> 10 mins) and total and average amount of time spent in those sedentary bouts among 10- to 12-year-old Belgian children. The total sample included 354 children (mean age: 10.9 ± 0.7 years; 59% girls) with valid ActiGraph accelerometer data at pre- and posttest. Only few and small intervention effects were found, namely on total time spent in sedentary bouts immediately after school hours (4-6PM; β = -3.51mins) and on average time spent in sedentary bouts before school hours (6-8.30AM; β = -4.83mins) and immediately after school hours in favor of children from intervention schools (β = -2.71mins). Unexpectedly, girls from intervention schools decreased the number of breaks during school hours (8.30AM-4PM; β = -23.45breaks) and increased the number of sedentary bouts on a weekend day (β = +0.90bouts), whereas girls in control schools showed an increase in number of breaks and a decrease in number of bouts. In conclusion, UP4FUN did not have a consistent or substantial effect on breaking up children’s sedentary time and these data suggest that more intensive and longer lasting interventions are needed.
The Contribution of Youth Sport Football to Weekend Physical Activity for Males Aged 9 to 16 Years: Variability Related to Age and Playing Position
Authors: Fenton Sally A.M. , Duda Joan L. , Barrett Timothy
Published: November 2014

The aims of this study were (1) to determine minutes of moderate-to-vigorous physical activity (PA) and vigorous PA accrued in youth sport football (also internationally referred to as soccer), and the contribution toward daily weekend moderate-to-vigorous PA and vigorous PA for males aged 9-16 years, and (2) to investigate variability in these outcomes related to age and playing position. One hundred and nine male grassroots footballers (Mean age = 11.98 ± 1.75 years) wore a GT3x accelerometer for 7 days. Weekend youth sport football participation and playing position were recorded. Youth sport football moderate-to-vigorous PA (M = 51.51 ± 17.99) and vigorous PA (M = 27.78 ± 14.55) contributed 60.27% and 70.68% toward daily weekend moderate-to-vigorous PA and vigorous PA, respectively. Overall, 36.70% of participants accumulated ≥60 min moderate-to-vigorous PA and 69.70% accrued < 20 min of vigorous PA during youth sport. For participants aged 13 to16 years, youth sport football moderate-to-vigorous PA and vigorous PA were significantly higher, and contributed a greater amount toward daily weekend moderate-to-vigorous PA and vigorous PA than for participants aged 9-12 years (p = >.01). Youth sport football is an important source of moderate-to-vigorous PA and vigorous PA at the weekend for male youth, and particularly for adolescents. Participation may offer opportunity for weekend engagement in vigorous PA toward health enhancing levels.
Associations Between Home Environment and After-School Physical Activity and Sedentary Time Among 6th Grade Children
Authors: Lau Erica Y. , Barr-Anderson Daheia J. , Dowda Marsha , Forthofer Melinda , Saunders Ruth P. , Pate Russell R.
Published: November 2014

This study examined associations of various elements of the home environment with after-school physical activity and sedentary time in 671 6th-grade children (Mage = 11.49 ± 0.5 years). Children’s after-school total physical activity, moderate-to-vigorous physical activity, and sedentary time were measured by accelerometry. Parents completed surveys assessing elements of the home social and physical environment. Mixed-model regression analyses were used to examine the associations between each element of the home environment and children’s after-school physical activity and sedentary time. Availability of home physical activity resources was associated positively with after-school total physical activity and negatively with after-school sedentary time in boys. Parental support was associated positively with after-school total physical activity and MVPA and negatively with after-school sedentary time in girls. The home physical environment was associated with boys’ after-school physical activity and sedentary time, whereas the home social environment was associated with girls’ after-school physical activity and sedentary time.
The Blood Pressure Response to Exercise in Youth with Impaired Glucose Tolerance and Type 2 Diabetes
Authors: Yardley Jane E. , Hay Jacqueline , MacMillan Freya , Wittmeier Kristy , Wicklow Brandy , MacIntosh Andrea , McGavock Jonathan
Published: November 2014

Type 2 diabetes is associated with hypertension and an increased risk of cardiovascular disease. In adults, blood pressure (BP) responses to exercise are predictive of these complications. To determine if the hemodynamic response to exercise is exaggerated in youth with dysglycemia (DG) compared with normoglycemic overweight/obese (OB) and healthy weight (HW) controls a cross-sectional comparison of BP and heart rate (HR) responses to graded exercise to exhaustion in participants was performed. DG and OB youth were matched for age, BMI z-score, height and sex. Systolic (SBP) and diastolic BP (DBP) were measured every 2 min, and HR was measured every 1 min. SBP was higher in OB and DG compared with HW youth at rest (p > .001). Despite working at lower relative workloads compared with HW, the BP response was elevated during exercise in OB and DG. For similar HR and oxygen consumption rates, BP responses to exercise were slightly higher in OB and DG compared with HW. OB and DG youth both display elevated resting and exercise BP relative to HW peers. Obesity may play a greater role than dysglycemia in the exaggerated BP response to exercise in youth.
Kinematics and Kinetics of Maximum Running Speed in Youth Across Maturity
Authors: Rumpf Michael C. , Cronin John B. , Oliver Jonathan , Hughes Michael
Published: November 2014

Sprinting is an important physical capacity and the development of sprint ability can take place throughout the athlete’s growth. The purpose of this study therefore was to determine if the kinematics and kinetics associated with maximum sprint velocity differs in male youth participants of different maturity status (pre, mid- and postpeak height velocity (PHV)) and if maximum sprint velocity is determined by age, maturity or individual body size measurement. Participants (n = 74) sprinted over 30 meters on a nonmotorized treadmill and the fastest four consecutive steps were analyzed. Pre-PHV participants were found to differ significantly (p < .05) to mid- and post-PHV participants in speed, step length, step frequency, vertical and horizontal force, and horizontal power (~8-78%). However, only relative vertical force and speed differed significantly between mid and post-PHV groups. The greatest average percent change in kinetics and kinematics was observed from pre- to mid-PHV (37.8%) compared with mid- to post- PHV groups (11.6%). When maturity offset was entered as a covariate, there was no significant difference in velocity between the three groups. However, all groups were significantly different from each other when age was chosen as the covariate. The two best predictors of maximal velocity within each maturity group were power and horizontal force (R2 = 97−99%) indicating the importance of horizontal force application while sprinting. Finally, maturity explained 83% of maximal velocity across all groups.
Targeting Bone and Fat with Novel Exercise for Peripubertal Boys: The CAPO Kids Trial
Authors: Nogueira Rossana C. , Weeks Benjamin K. , Beck Belinda R.
Published: November 2014

Our goal was to test the effect of a brief, novel bone- and fat-targeted exercise program on bone, muscle, and fat in healthy pre and peripubertal boys. We conducted a 10-min, 3/wk capoeira and jumping exercise intervention for 9 months with year 5 and 6 school boys. Anthropometrics, maturity, heart rate, blood pressure, maximal vertical jump, aerobic capacity and calcaneal broadband ultrasound attenuation and stiffness index (BUA and SI; Achilles, GE) were assessed. Bone, lean and fat tissue (DXA; XR800, Norland), and parameters of bone geometry (pQCT, XCT3000, Stratec) were measured from a subsample of 36 boys. Of 188 boys (10.6 ± 0.5 yr) who consented, 172 completed all testing; 104 exercisers (EX) and 68 controls (CON). 30 EX and 6 CON participants underwent DXA and pQCT measures. EX improved BUA (+4.3% vs. +2.1%, p = .035), waist circumference (+2.8% vs. +6.2%, p = .001), heart rate (-5.3% vs. +1.5%, p = .005), maximal vertical jump (+12.2% vs. −0.3%, p = .001) and estimated maximal oxygen consumption (+9.1% vs. +1.2%, p = .001) compared with CON. Three 10-min sessions of capoeira and jumping per week improved calcaneal bone and metabolic health of pre and peripubertal boys over the course of a school year with little disruption to the academic schedule.
Use of Physical Activity Self-Management Strategies by High School Students
Authors: Trost Stewart G. , Hutley Jan
Published: November 2014

Teaching adolescents to use self-management strategies may be an effective approach to promoting lifelong physical activity (PA). However, the extent to which adolescents use self-management strategies and their impact on current PA have not been studied previously. The aims of this study were 1) to describe the prevalence of self-management strategy use in adolescents; and 2) to determine relationships between self-management strategy use, PA self-efficacy, and PA participation. 197 students completed questionnaires measuring use of self-management strategies, self-efficacy, and PA behavior. The most prevalent self-management strategies (>30%) were thinking about the benefits of PA, making PA more enjoyable, choosing activities that are convenient, setting aside time to do PA, and setting goals to do PA. Fewer than 10% reported rewarding oneself for PA, writing planned activities in a book or calendar, and keeping charts of PA. Use of self-management strategies was associated with increased self-efficacy (r = .47, p < .001) and higher levels of PA (r = .34 p < .001). A 1-unit difference in self-management strategy scores was associated with a ~fourfold increase in the probability of being active (OR = 3.7, 95% CI = 1.8-7.4). Although strongly associated with PA, a relatively small percentage of adolescents routinely use self-management strategies.
Acute Effects of Energy Deficit Induced by Moderate-Intensity Exercise or Energy-Intake Restriction on Postprandial Lipemia in Healthy Girls
Authors: Thackray Alice Emily , Barrett Laura Ann , Tolfrey Keith
Published: November 2014

Eleven healthy girls (mean ± SD: age 12.1 ± 0.6 years) completed three 2-day conditions in a counterbalanced, crossover design. On day 1, participants either walked at 60 (2)% peak oxygen uptake (energy deficit 1.55[0.20] MJ), restricted food energy intake (energy deficit 1.51[0.25] MJ) or rested. On day 2, capillary blood samples were taken at predetermined intervals throughout the 6.5 hr postprandial period before, and following, the ingestion of standardized breakfast and lunch meals. Fasting plasma triacylglycerol concentrations (TAG) was 29% and 13% lower than rest control in moderate-intensity exercise (effect size [ES] = 1.39, p = .01) and energy-intake restriction (ES = 0.57, p = .02) respectively; moderate-intensity exercise was 19% lower than energy-intake restriction (ES = 0.82, p = .06). The moderate-intensity exercise total area under the TAG versus time curve was 21% and 13% lower than rest control (ES = 0.71, p = .004) and energy-intake restriction (ES = 0.39, p = .06) respectively; energy-intake restriction was marginally lower than rest control (-10%; ES = 0.32, p = .12). An exercise-induced energy deficit elicited a greater reduction in fasting plasma TAG with a trend for a larger attenuation in postprandial plasma TAG than an isoenergetic diet-induced energy deficit in healthy girls.
Tuberculous lymphadenitis and borderline leprosy in a patient with isolated unconjugated hyperbilirubinaemia
Authors: Magazine Rahul , Chogtu Bharti , Manu Mohan K , Shahul Hameed Aboobackar
Published: November 2014

A 35-year-old man was diagnosed with tuberculous lymphadenitis and multibacillary borderline tuberculoid leprosy. On investigation, isolated unconjugated hyperbilirubinaemia was detected and evaluation led us to conclude that the probable cause was Gilbert's syndrome. He was successfully managed by administration of chemotherapy for the treatment of both the mycobacterial infections, with no adverse effects on liver function tests.
Learning Feature Representations with a Cost-Relevant Sparse Autoencoder
Authors: Längkvist Martin , Loutfi Amy
Published: November 2014

There is an increasing interest in the machine learning community to automatically learn feature representations directly from the (unlabeled) data instead of using hand-designed features. The autoencoder is one method that can be used for this purpose. However, for data sets with a high degree of noise, a large amount of the representational capacity in the autoencoder is used to minimize the reconstruction error for these noisy inputs. This paper proposes a method that improves the feature learning process by focusing on the task relevant information in the data. This selective attention is achieved by weighting the reconstruction error and reducing the influence of noisy inputs during the learning process. The proposed model is trained on a number of publicly available image data sets and the test error rate is compared to a standard sparse autoencoder and other methods, such as the denoising autoencoder and contractive autoencoder.
Some Scheduling Problems on a Single Machine with General Job Effects of Position-Dependent Learning and Start-Time-Dependent Deterioration
Authors: Kung Jan-Yee , Shu Ming-Hung
Published: November 2014

Job learning and deterioration coexist in many realistic machine-job scheduling situations. However, in literature, the constructed forms of the machine scheduling models with job learning and/or deteriorating effects were specific types of functions, which constrained their applicability in practice. This paper introduces a new single-machine scheduling model, where the actual processing time of a job is a general function of its starting time as well as scheduled position, which shows a broad generalization in contrast to that of certain existing models. For three objectives corresponding to the single-machine scheduling problem–total weighted completion time, discounted total weighted completion time, and maximum lateness — this paper presents their respective approximation result on the basis of the worst-case bound analysis from the optimal algorithm. The results demonstrate that under our proposed model, minimization of scheduling operations such as the makespan, sum of the kth power of completion times, and total lateness are polynomially solvable. Moreover, under some feasible conditions for the scheduling parameters, the minimum optimization problems of the total weighted completion time, discounted total weighted completion time, maximum lateness, and total tardiness are all recognized as polynomial forms and their solutions are provided.
Proof of a conjecture of Guy on class numbers
Authors: Chua Lynn , Gunby Benjamin , Park Soohyun , Yuan Allen
Published: November 2014

It is well known that for any prime p ≡ 3 (mod 4), the class numbers of the quadratic fields [Formula: see text] and [Formula: see text] and h(-p), respectively, are odd. It is natural to ask whether there is a formula for h(p)/h(-p) modulo powers of 2. We show the formula h(p) ≡ h(-p)m(p) (mod 16), where m(p) is an integer defined using the "negative" continued fraction expansion of [Formula: see text]. Our result solves a conjecture of Richard Guy.
Effects of stenoses on non-Newtonian flow of blood in blood vessels
Authors: Prakash Om , Makinde O. D. , Singh S. P. , Jain Nidhi , Kumar Devendra
Published: November 2014

In this paper, a mathematical model for steady blood flow through blood vessels with uniform cross-section in stenoses arteries has been proposed. Blood is assumed to be non-Newtonian, incompressible and homogeneous fluid. Blood in human artery is represented as Bingham plastic fluid. Expressions for flow rate, wall shear stress, and resistance to flow against stenoses size have been obtained. Obtained results indicate that stenoses size decreases the flow rate and increases the wall shear stress as well as resistance to flow.
An island biogeography model for beta diversity and endemism: The roles of speciation, extinction and dispersal
Authors: Chen Youhua
Published: November 2014

A community composition island biogeography model was developed to explain and predict two community patterns (beta diversity and endemism) with the consideration of speciation, extinction and dispersal processes. Results showed that rate of speciation is positively and linearly associated with beta diversity and endemism, that is, increasing species rates typically could increase the percentage of both endemism and beta diversity. The influences of immigration and extinction rates on beta diversity and endemism are nonlinear, but with numerical simulation, I could observe that increasing extinction rates would lead to decreasing percentage of endemism and beta diversity. The role of immigration rate is very similar to that of speciation rate, having a positive relationship with beta diversity and endemism. Finally, I found that beta diversity is closely related to the percentage of endemism. The slope of this positive relationship is determined jointly by different combinations of speciation, extinction and immigration rates.
Toluidine blue O and porphyrin-mediated photodynamic therapy on three main pathogenic bacteria of periodontitis using portable LED phototherapy device
Authors: Jiang Xuewei , Fan Zhichao , Yu Yili , Shao Chenying , Suo Yuanzhen , Wei Xunbin , Zhou Yi
Published: November 2014

Photodynamic therapy (PDT) has been commonly used in treating many diseases, such as cancer and infectious diseases. We investigated the different effects of PDT on three main pathogenic bacteria of periodontitis — Prevotella melaninogenica (P.m.), Porphyromonas gingivalis (P.g.) and Aggregatibacter actinomycetemcomitans (A.a.). The portable red light-emitting diode (LED) phototherapy device was used to assess the exogenous PDT effects with different light doses and photosensitizer concentrations (Toluidine blue O, TBO). The portable blue LED phototherapy device was used to assess the endogenous PDT effects with the use of endogenous photosensitizers (porphyrin) under different light doses. We found out that both exogenous and endogenous PDT were able to restrict the growth of all the three bacteria significantly. Moreover, the optimal PDT conditions for these bacteria were obtained through this in vitro screening and could guide the clinical PDT on periodontitis.
Carbon-coated magnetic particles increase tissue temperatures after laser irradiation
Authors: Liu Shupeng , Chen Na , Pang Fufei , Chen Zhengyi , Wang Tingyun
Published: November 2014

Purpose: This work focused on the investigation the hyperthermia performance of the carbon-coated magnetic particles (CCMPs) in laser-induced hyperthermia. Materials and methods: We prepared CCMPs using the organic carbonization method, and then characterized them with transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectrophotometry, vibrating sample magnetometer (VSM) and X-ray diffraction (XRD). In order to evaluate their performance in hyperthermia, the CCMPs were tested in laser-induced thermal therapy (LITT) experiments, in which we employed a fully distributed fiber Bragg grating (FBG) sensor to profile the tissue's dynamic temperature change under laser irradiation in real time. Results: The sizes of prepared CCMPs were about several micrometers, and the LITT results show that the tissue injected with the CCMPs absorbed more laser energy, and its temperature increased faster than the contrast tissue without CCMPs. Conclusions: The CCMPs may be of great help in hyperthermia applications.
SPIN TRANSPORT IN MULTIPLY CONNECTED FRACTAL CONDUCTORS
Authors: LEE BO-RAY , CHANG CHING-RAY , KLIK IVO
Published: November 2014

We consider spin and charge transport in a Sierpinski planar carpet; the interest here is its unique geometry. We analyze the fractal conductor as a combination of multiply connected quantum wires, and we observe the evolution of the transmission envelope in different fractal generations. For a fractal conductor dominated by resonant modes the transmission is characterized by strong fluctuations and conduction gaps. We show that charge and spin transport have different responses both to the presence of defects and to applied bias. At a high bias, or in a high-order fractal generation, spin accumulation is separated from charge accumulation because the larger drift velocity needs a longer polarization length, and the sample may turn into an insulator by the action of the defects. Our results are calculated numerically using the Keldysh Green function within the tight-binding framework.
Repeated High Intensity Bouts with Long Recovery: Are Bicarbonate or Carbohydrate Supplements an Option?
Authors: Stöggl Thomas , Torres-Peralta Rafael , Cetin Ebru , Nagasaki Masaru
Published: November 2014

The effects of varying recovery modes and the influence of preexercise sodium bicarbonate and carbohydrate ingestion on repeated high intensity performance, acid-base response, and recovery were analyzed in 12 well-trained males. They completed three repeated high intensity running bouts to exhaustion with intervening recovery periods of 25 min under the following conditions: sodium bicarbonate, active recovery (BIC); carbohydrate ingestion, active recovery (CHO); placebo ingestion, active recovery (ACTIVE); placebo ingestion, passive recovery (PASSIVE). Blood lactate (BLa), blood gases, heart rate, and time to exhaustion were collected. The three high intensity bouts had a duration of138±9, 124±6, and121±6 s demonstrating a decrease from bout 1 to bout 3. Supplementation strategy had no effect on performance in the first bout, even with differences in pH and bicarbonate (HCO3-). Repeated sprint performance was not affected by supplementation strategy when compared to ACTIVE, while PASSIVE resulted in a more pronounced decrease in performance compared with all other interventions. BIC led to greater BLa, pH, and HCO3-values compared with all other interventions, while for PASSIVE the opposite was found. BLa recovery was lowest in PASSIVE; recovery in pH, and HCO3-was lower in PASSIVE and higher in BIC.
Antimicrobial Studies of N-Heterocyclic Carbene Silver Complexes Containing Benzimidazol-2-ylidene Ligand
Authors: Gök Yetkin , Sarı Yakup , Akkoç Senem , Özdemir İlknur , Günal Selami
Published: November 2014

Seven novel 4-vinylbenzyl substituted N-heterocyclic carbene (NHC) silver complexes were synthesized from different benzimidazolium salts and silver (I) oxide in dichloromethane at room temperature. These new 4-vinylbenzyl substituted NHC silver complexes were characterized by spectroscopic (NMR, IR) and elemental analysis techniques. Using the agar dilution procedure, the antimicrobial activities of these synthesized new compounds were investigated against Gram (+)/(−) bacterial and fungal strains. These NHC silver complexes showed effective activities against Escherichia coli, Pseudomonas aeruginosa (Gram-negative bacterial strains), Enterococcus faecalis, Staphylococcus aureus (Gram-positive bacterial strains), and Candida tropicalis and Candida albicans (fungal strains).
An Image Encryption Algorithm Based on Balanced Pixel and Chaotic Map
Authors: Zhang Jian , Zhang Yutong
Published: November 2014

Image encryption technology has been applied in many fields and is becoming the main way of protecting the image information security. There are also many ways of image encryption. However, the existing encryption algorithms, in order to obtain a better effect of encryption, always need encrypting several times. There is not an effective method to decide the number of encryption times, generally determined by the human eyes. The paper proposes an image encryption algorithm based on chaos and simultaneously proposes a balanced pixel algorithm to determine the times of image encryption. Many simulation experiments have been done including encryption effect and security analysis. Experimental results show that the proposed method is feasible and effective.
Active Fault Tolerant Control Based on Bond Graph Approach
Authors: Allous Manel , Zanzouri Nadia
Published: November 2014

This paper proposes a structural fault recoverability analysis using the bond graph (BG) approach. Indeed, this tool enables structural analysis for diagnosis and fault tolerant control (FTC). For the FTC, we propose an approach based on the inverse control using the inverse BG. The fault tolerant control method is also compared with another approach. Finally, simulation results are presented to show the performance of the proposed approach.
Clinical and Radiographic Assessment of Secondary Bone Graft Outcomes in Cleft Lip and Palate Patients
Authors: Khalil W. , de Musis C. R. , Volpato L. E. R. , Veiga K. A. , Vieira E. M. M. , Aranha A. M.
Published: November 2014

Purpose. To compare the results of secondary alveolar bone grafts in patients with complete cleft lip and cleft lip and palate using 2 radiographic scales and according to the rate of canine eruption through the newly formed bone. Materials and Methods. We analyzed pre- and postoperative radiographs of 36 patients for the amount of bone in the cleft site according to the Bergland and Chelsea scales. The associations between the variables and the correlation between the scales were measured. Results. A total of 54.2% and 20.8% of cases were classified as type I and type II, respectively, using the Bergland scale, whereas 50% and 22.5% were classified as types A and C, respectively, using the Chelsea scale. A positive correlation between the 2 scales was observed. In 33.3% of males, 58.3% of females, 54.5% of unilateral cleft cases, and 12.5% of bilateral cleft cases, the permanent canines had erupted. Bone grafts performed prior to canine eruption achieved more satisfactory results. Conclusions. Our results suggest that both radiographic scales are important tools for the evaluation of bone grafts. Additionally, longer time periods of evaluation were associated with improved results for patients with secondary alveolar bone grafts.
Sympatric Clupeoid Fish Larvae in the Northeastern Mediterranean: Coexistence or Avoidance?
Authors: Tsikliras Athanassios C.
Published: November 2014

The summer (July 2002 and 2003) larval concentrations of two commercially important clupeoid species (order: Clupeiformes), the European anchovy (Engraulis encrasicolus) and round sardinella (Sardinella aurita), were measured in Kavala Gulf (northern Aegean Sea), in order to examine their distribution patterns. Anchovy was generally most abundant, reaching 13 852 larvae 10 m−2 in 2003 and occurred in more stations compared to round sardinella. Despite the spawning of both species occurring across the entire gulf, the general spatial distribution of their larvae was different, with European anchovy larvae occupying the entire gulf and round sardinella larvae mainly concentrated at offshore stations. The reason proposed for the spatial segregation of their larvae is direct competition for resources. Yet, coexistence of the two species was observed in frontal areas with abundant food resources that prevent competition.
High Order Fefferman-Phong Type Inequalities in Carnot Groups and Regularity for Degenerate Elliptic Operators plus a Potential
Authors: Niu Pengcheng , Zhang Kelei
Published: November 2014

Let{X1,X2,…,Xm}be the basis of space of horizontal vector fields in a Carnot groupG=(Rn;∘) (m<n). We prove high order Fefferman-Phong type inequalities inG. As applications, we derive a prioriLp(G)estimates for the nondivergence degenerate elliptic operatorsL=-∑i,j=1maij(x)XiXj+V(x)withVMOcoefficients and a potentialVbelonging to an appropriate Stummel type class introduced in this paper. Some of our results are also new even for the usual Euclidean space.
Coefficient Estimates for a New Subclass of Analytic and Bi-Univalent Functions Defined by Hadamard Product
Authors: Bulut Serap
Published: November 2014

We introduce and investigate a new general subclass ℋΣλ,μ(φ;Θ) of analytic and bi-univalent functions in the open unit disk U. For functions belonging to this class, we obtain estimates on the first two Taylor-Maclaurin coefficients |a2| and |a3|.
OMFM: A Framework of Object Merging Based on Fuzzy Multisets
Authors: Yue Lin , Zuo Wanli , Feng Lizhou , Guo Lin
Published: November 2014

Information fusion is a process of merging information from multiple sources into a new set of information. Existing work on information fusion is applicable in various scenarios such as multiagent system, group decision making, and multidocument summarization. This paper intends to develop an effective framework to solve object merging problem based on fuzzy multisets. The objects defined in this paper are data segments in document fusion task, referring to the concepts with semantic‐related terms of different semantic relations embedded. The fundamental operation is the merge function mapping data segments in multiple fuzzy multisets onto one object, which is a solution. Under this framework, we define quality measures of purity and entropy to quantify the quality of the solutions, balancing accurateness, and completeness of the results. Merge function that yields this kind of solutions is VI‐optimal merge function and a series of theoretical properties concerning it are studied. Finally, we investigate the proposed framework in a special application scenario (i.e., document fusion) which is related to the task of multidocument summarization and show how the framework works with illustrative example.
Impact of Orthodontic Decompensation on Bone Insertion
Authors: Guedes Fabio Pinto , Capelozza Filho Leopoldino , Garib Daniela Gamba , Nary Filho Hugo , Borgo Evandro José , Cardoso Mauricio de Almeida
Published: November 2014

There has always been concern in determining the relationship between orthodontic tooth movement and the consequent biological costs to the periodontium and tooth root. The possibility of evaluating the tooth and bone morphology by CBCT allows more accurate analysis of qualitative and quantitative aspects of these processes. This paper presents a case report of a 20-year-old male patient with Class III malocclusion and hyperdivergent facial pattern, who was surgically treated. A significant amount of labial movement of mandibular incisors was performed during orthodontic treatment before surgery. CBCT was used for evaluation of buccal and lingual bone plates before and after tooth decompensation. The changes in the bone insertion level of maxillary and mandibular incisors in the present case encourage a reflection on the treatment protocol in individuals with dentoskeletal discrepancies.
On Complexities of Impact Simulation of Fiber Reinforced Polymer Composites: A Simplified Modeling Framework
Authors: Alemi-Ardakani M. , Milani A. S. , Yannacopoulos S.
Published: November 2014

Impact modeling of fiber reinforced polymer composites is a complex and challenging task, in particular for practitioners with less experience in advanced coding and user-defined subroutines. Different numerical algorithms have been developed over the past decades for impact modeling of composites, yet a considerable gap often exists between predicted and experimental observations. In this paper, after a review of reported sources of complexities in impact modeling of fiber reinforced polymer composites, two simplified approaches are presented for fast simulation of out-of-plane impact response of these materials considering four main effects: (a) strain rate dependency of the mechanical properties, (b) difference between tensile and flexural bending responses, (c) delamination, and (d) the geometry of fixture (clamping conditions). In the first approach, it is shown that by applying correction factors to the quasistatic material properties, which are often readily available from material datasheets, the role of these four sources in modeling impact response of a given composite may be accounted for. As a result a rough estimation of the dynamic force response of the composite can be attained. To show the application of the approach, a twill woven polypropylene/glass reinforced thermoplastic composite laminate has been tested under 200 J impact energy and was modeled in Abaqus/Explicit via the built-in Hashin damage criteria. X-ray microtomography was used to investigate the presence of delamination inside the impacted sample. Finally, as a second and much simpler modeling approach it is shown that applying only a single correction factor over all material properties at once can still yield a reasonable prediction. Both advantages and limitations of the simplified modeling framework are addressed in the performed case study.