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Objective: The proposed study aimed to assess the utility of tubeless PCNL in terms of efficacy and safety when compared with the standard tubed PCNL. Materials & Methods: In this study 280 patients (age ranged 08-70 years) who underwent PCNL were included. Results: The patients were from both genders i.e., 156 males and 124 females. Out of 280 patients, 140 had a 16 FR nephrostomy tube (Group A) whiles an equal number had 4.8F DJ Stent (Group B) for postoperative drainage. A comparison of the postoperative outcome among the two groups was made for a period of two years (November 2017 to October 2019). Neither any significant difference was found in the mean stone size, operative time, nor was stone-free status, nor any major complication observed. The mean hospital stay for group A and group B was 4.5 days (range 3 to 6) and 3.2 days (range 2 to 4) respectively. An early postoperative wound soakage was found in 18 (12.8%) cases of group A in contrast to the group B patients in whom only 2 (1.4%) had soakage. Conclusion: It was concluded that Tubeless PCNL as compared to the standard tubed PCNL was found more efficacious and safer and it should be adopted as a routine procedure.

A huge body of research is concentrated on developing advance load control strategies for reducing energy consumption and ensuring smooth operation of power system. Air conditioning loads are considered major energy consuming electrical loads in residential and business buildings, and that may cause significant rise in energy consumption. This paper presents an implementation of fuzzy controller with different number and shapes of membership functions for smoothing energy consumption of an air conditioning load while dealing with thermal disturbances. Simulations are conducted in MATLAB Simulink and the results demonstrate that the fuzzy controller with triangular membership function gives the desired performance with an error of less than 1% and saves 25% energy consumption. The obtained results are found effective in terms of smoothing energy consumption pattern of an air conditioning load without compromising consumer' s comfort. Performance of the designed controller is also compared with different controllers including self-tuning adaptive fuzzy controller, linear quadratic regulator (LQR) and nonlinear controllers. The presented fuzzy controller stands-out in terms of desired performance, simplicity and implementation.

Purpose Over the past few decades, the flow around circular cylinders has been one of the highly researched topics in the field of offshore engineering and fluid-structure interaction (FSI). In the current study, numerical simulations for flow around a fixed circular cylinder are performed at Reynolds number (Re) = 3900 with the LES method using the ICEM-CFD and ANSYS Fluent tool for meshing and analysis, respectively. Previously, similar studies have been conducted at the same Reynolds number, but there have been discrepancies in the results, particularly in calculating the recirculation length and angle of separation. In addition, the purpose of this study is to address the impact of time interval averaging to obtain the fully converged solution. Design/methodology/approach This study presents the LES method, using the ICEM-CFD and ANSYS fluent tool for meshing and analysis. Findings In the current study, turbulence statistics are sampled for 25, 50, 75 and 100 vortex-shedding cycles with the CFL value O (1). The recirculation length, angle of separation, hydrodynamic coefficients and the wake behind the cylinder are investigated up to ten diameters. The drag coefficient and Strouhal number are observed to be less sensitive, whereas the recirculation length appeared to be highly dependent on the average time statistics and the non-dimensional time step. Similarly, the mean streamwise and cross-flow velocity are observed to be sensitive to the average time statistics and non-dimensional time step in the wake region near the cylinder. Originality/value In the current investigation, turbulence statistics are sampled for 25, 50, 75 and 100 vortex-shedding cycles with the CFL value O (1), using large eddy simulation method at Re = 3900 around a circular cylinder. The impact of time interval averaging to obtain the fully converged mean flow field is addressed. No such consideration is yet published in the literature.

This article proposes an automatic longitudinal deceleration based method for multi-wheel vehicle rollover safety in autonomous mode. The information of lateral acceleration and vehicle roll angle is used to generate the longitudinal acceleration at which the vehicle will remain stable to rollover. The lateral and roll dynamics are coupled with longitudinal dynamics using a potential field function for lateral acceleration. This virtual potential field is developed on g-g diagram which represents vehicle portrait of lateral and longitudinal acceleration on abscissa and ordinate respectively. The motion of vehicle is represented by a point moving on this phase portrait of g-g diagram. TruckSim model of multi-wheel military vehicle with in-wheel motors is used with this algorithm which shows that the vehicle is less susceptible to rollover. The safe longitudinal acceleration is achieved by torque control of in-wheel motors fitted in each wheel. Using this method, the vehicle followed the desired trajectory as higher speeds which are safe. This is particularly useful for vehicle autonomous driving with rollover stability.

Quartz Tuning Fork (QTF) based sensors are used for Scanning Probe Microscopes (SPM), in particular for near-field scanning optical microscopy. Highly sharp Tungsten (W) tips with larger cone angles and less tip diameter are critical for SPM instead of platinum and iridium (Pt/Ir) tips due to their high-quality factor, conductivity, mechanical stability, durability and production at low cost. Tungsten is chosen for its ease of electrochemical etching, yielding high-aspect ratio, sharp tips with tens of nanometer end diameters, while using simple etching circuits and basic electrolyte chemistry. Moreover, the resolution of the SPM images is observed to be associated with the cone angle of the SPM tip, therefore Atomic-Resolution Imaging is obtained with greater cone angles. Here, the goal is to chemically etch W to the smallest possible tip apex diameters. Tips with greater cone angles are produced by the custom etching procedures, which have proved superior in producing high quality tips. Though various methods are developed for the electrochemical etching of W wire, with a range of applications from scanning tunneling microscopy (SPM) to electron sources of scanning electron microscopes, but the basic chemical etching methods need to be optimized for reproducibility, controlling cone angle and tip sharpness that causes problems for the end users. In this research work, comprehensive experiments are carried out for the production of tips from 0.4 mm tungsten wire by three different electrochemical etching techniques, that is, Alternating Current (AC) etching, Meniscus etching and Direct Current (DC) etching. Consequently, sharp and high cone angle tips are obtained with required properties where the results of the W etching are analyzed, with optical microscope, and then with field emission scanning electron microscopy (FE-SEM). Similarly, effects of varying applied voltages and concentration of NaOH solution with comparison among the produced tips are investigated by measuring their cone angle and tip diameter. Moreover, oxidation and impurities, that is, removal of contamination and etching parameters are also studied in this research work. A method has been tested to minimize the oxidation on the surface and the tips were characterized with scanning electron microscope (SEM).

Upper limb assist exoskeleton robot requires quantitative techniques to assess human motor function and generate command signal for robots to act in compliance with human motion. To asses human motor function, we present Desired Motion Intention (DMI) estimation algorithm using Muscle Circumference Sensor (MCS) and load cells. Here, MCS measures human elbow joint torque using human arm kinematics, biceps/triceps muscle model and physiological cross sectional area of these muscles whereas load cells play a compensatory role for the torque generated by shoulder muscles as these cells measure desire of shoulder muscles to move the arm and not the internal activity of shoulder muscles. Furthermore, damped least square algorithm is used to estimate Desired Motion Intention (DMI) from these torques. To track this estimated DMI, we have used passivity based adaptive control algorithm. This control techniques is particular useful to adapt modeling error of assist exoskeleton robot for different subjects. Proposed methodology is experimentally evaluated on seven degree of freedom upper limb assist exoskeleton. Results show that DMI is well estimated and tracked for assistance by the proposed control algorithm.

The need for human body posture robots has led researchers to develop dexterous design of exoskeleton robots. Quantitative techniques to assess human motor function and generate commands for robots were required to be developed. In this paper, we present a passivity based adaptive control algorithm for upper limb assist exoskeleton. The proposed algorithm can adapt to different subject parameters and provide efficient response against the biomechanical variations caused by subject variations. Furthermore, we have employed the Particle Swarm Optimization technique to tune the controller gains. Efficacy of the proposed algorithm method is experimentally demonstrated using a seven degree of freedom upper limb assist exoskeleton robot. The proposed algorithm was found to estimate the desired motion and assist accordingly. This algorithm in conjunction with an upper limb assist exoskeleton robot may be very useful for elderly people to perform daily tasks.

A steer-by-wire (SbW) system, also known as a next-generation steering system, is one of the core elements of autonomous driving technology. Navigating a SbW system road vehicle in varying driving conditions requires an adaptive and robust control scheme to effectively compensate for the uncertain parameter variations and external disturbances. Therefore, this article proposed an adaptive global fast sliding mode control (AGFSMC) for SbW system vehicles with unknown steering parameters. First, the cooperative adaptive sliding mode observer (ASMO) and Kalman filter (KF) are established to simultaneously estimate the vehicle states and cornering stiffness coefficients. Second, based on the best set of estimated dynamics, the AGFSMC is designed to stabilize the impact of nonlinear tire-road disturbance forces and at the same time to estimate the uncertain SbW system parameters. Due to the robust nature of the proposed scheme, it can not only handle the tire–road variation, but also intelligently adapts to the different driving conditions and ensures that the tracking error and the sliding surface converge asymptotically to zero in a finite time. Finally, simulation results and comparative study with other control techniques validate the excellent performance of the proposed scheme.

Ali, Ashfaq, Zhou, Zhixiang, Waseem, Muhammad, Khan, Muhammad Fiaz, Ali, Ishtiaq, Asad, Muhammad, Qashqaei, Ali Turk (2017): An assessment of food habits and altitudinal distribution of the Asiatic black bear (Ursus thibetanus) in the Western Himalayas, Pakistan. Journal of Natural History 51 (11-12): 689-701, DOI: 10.1080/00222933.2017.1303097, URL: http://dx.doi.org/10.1080/00222933.2017.1303097

In this study, significant risk factors of Helicobacter pylori infection in Lahore are investigated through a case-control study by using descriptive and analytical approaches. A sample of 362 subjects was selected from the Gastroenterology Departments and OPDs of different hospitals of Lahore. About 25 risk factors with sub categories were included in the study. For bivariate analysis, the chi-square, phi/v statistics and Kendall’s tau-b are used. From descriptive analysis, it was found that the persons who eat from restaurants have more risk of infection as compare to persons who eat homemade food. By the descriptive analysis, it was also observed that risk of Helicobacter pylori infection increases with an increase in the number of family members per house and in the number of persons living per room. Furthermore, similar results were observed in the bivariate analysis. In the analysis, the five risk factors including age, food eat, food liked, dental complains and number of persons living per room are found to be positively significant having the odds ratios and 95% confidence intervals of odds ratios (1.025; 1.003-1.047), (9.596; 4.767-19.314), (3.500; 1.509-8.119), (3.204; 1.685-6.094) and (2.772; 1.496-5.139), respectively. While the three risk factors including usage of tea, educational level and sewerage system are found to be negatively significant having odds ratios and 95% confidence intervals for the odds ratios (0.221; 0.119-0.411), (0.216; 0.115-0.404) and (0.401; 0.218-0.738), respectively, which indicates that these three risk factors are protective factors against Helicobacter pylori infection. According to this study, the subjects who eat from restaurants have higher risk of Helicobacter pylori infection as compared to all other risk factors.

Summary The glucocorticoid receptor (GR) is a potent metabolic regulator and a major drug target. While GR is known to play integral roles in circadian biology, its rhythmic genomic actions have never been characterized. Here we mapped GR’s chromatin occupancy in mouse livers throughout the day and night cycle. We show how GR partitions metabolic processes by time-dependent target gene regulation and controls circulating glucose and triglycerides differentially during feeding and fasting. Highlighting the dominant role GR plays in synchronizing circadian amplitudes, we find that the majority of oscillating genes are bound by and depend on GR. This rhythmic pattern is altered by high-fat diet in a ligand-independent manner. We find that the remodeling of oscillatory gene expression and postprandial GR binding results from a concomitant increase of STAT5 co-occupancy in obese mice. Altogether, our findings highlight GR’s fundamental role in the rhythmic orchestration of hepatic metabolism.

Recent advances in the treatment of myelodysplastic syndromes have come from the use of the hypomethylating agents decitabine and azacitidine as well as the immunomodulatory drug lenalidomide. Their clinical benefit has been demonstrated by randomized phase III clinical trials, mostly in high-risk and del(5q) myelodysplastic syndromes, respectively. Neither drug, however, appears to eradicate myelodysplastic stem cells, and thus they currently do not represent curative options. Here, we review data from both clinical and translational research on those drugs to identify their molecular and cellular mechanisms of action and to delineate paths for improved treatment allocation and further therapeutic advances in myelodysplastic syndromes.

Need to develop human body's posture supervised robots, gave the push to researchers to think over dexterous design of exoskeleton robots. It requires to develop quantitative techniques to assess motor function and generate the command for the robots to act accordingly with complex human structure. In this paper, we present a new technique for the upper limb power exoskeleton robot in which load is gripped by the human subject and not by the robot while the robot assists. Main challenge is to find non-biological signal based human desired motion intention to assist as needed. For this purpose, we used newly developed Muscle Circumference Sensor (MCS) instead of electromyogram (EMG) sensors. MCS together with the force sensors is used to estimate the human interactive force from which desired human motion is extracted using adaptive Radial Basis Function Neural Network (RBFNN). Developed Upper limb power exoskeleton has seven degrees of freedom (DOF) in which five DOF are passive while two are active. Active joints include shoulder and elbow in Sagittal plane while abduction and adduction motion in shoulder joint is provided by the passive joints. To ensure high quality performance model reference based adaptive impedance controller is employed. Exoskeleton performance is evaluated experimentally by a neurologically intact subject which validates the effectiveness.

Navigating a robot in a dynamic environment is a challenging task, especially when the behavior of other agents such as pedestrians, is only partially predictable. Also, the kinodynamic constraints on robot motion add an extra challenge. This paper proposes a novel navigational strategy for collision avoidance of a kinodynamically constrained robot from multiple moving passive agents with partially predictable behavior. Specifically, this paper presents a new approach to identify the set of control inputs to the robot, named control obstacle, which leads it towards a collision with a passive agent moving along an arbitrary path. The proposed method is developed by generalizing the concept of nonlinear velocity obstacle (NLVO), which is used to avoid collision with a passive agent, and takes into account the kinodynamic constraints on robot motion. Further, it formulates the navigational problem as an optimization problem, which allows the robot to make a safe decision in the presence of various sources of unmodelled uncertainties. Finally, the performance of the algorithm is evaluated for different parameters and is compared to existing velocity obstacle-based approaches. The simulated experiments show the excellent performance of the proposed approach in term of computation time and success rate.

This paper propose the tire force distribution method for a rear wheel drive electric vehicle. This method is developed to improve the vehicle stability under the high speed cornering condition and save the electric energy. To control the lateral vehicle motion, the desired yaw moment is calculated by yaw rate control using PID theory. And Total desired longitudinal force is also determined by acceleration pedal signal. The tire force distribution method calculates the desired longitudinal tire forces at left and right wheel using the desired yaw moment and total desired longitudinal force and Maximum longitudinal tire force. And Maximum longitudinal tire force is determined by tire friction circle theory. The proposed method is verified by the simulation using CarSim software. And it is found from simulation results that the proposed method provides improvement vehicle stability and saving the electric energy under the high speed cornering condition.

Background Except during a 1-year period when BCG vaccine was not routinely administered, annual coverage of infants with Bacillus Calmette-Guerin (BCG) in Kazakhstan since 2002 has exceeded 95%. BCG preparations from different sources (Japan, Serbia, and Russia) or none were used exclusively in comparable 7-month time-frames, September through March, in 4 successive years beginning in 2002. Our objective was to assess relative effectiveness of BCG immunization. Methods/Findings We compared outcomes of birth cohorts from the 4 time-frames retrospectively. Three cohorts received vaccine from one of three manufacturers exclusively, and one cohort was not vaccinated. Cohorts were followed for 3 years for notifications of clinical TB and of culture-confirmed TB, and for 21 months for TB meningitis notifications. Prevention effectiveness based on relative risk of TB incidence was calculated for each vaccinated cohort compared to the non-vaccinated cohort. Although there were differences in prevention effectiveness observed among the three BCG vaccines, all were protective. The Japanese vaccine (currently used in Kazakhstan), the Serbian vaccine, and the Russian vaccine respectively were 69%, 43%, and 22% effective with respect to clinical TB notifications, and 92%, 82%, and 51% effective with respect to culture confirmed TB. All three vaccines were >70% effective with respect to TB meningitis. Limitations Potential limitations included considerations that 1) the methodology used was retrospective, 2) multiple risk factors could have varied between cohorts and affected prevention effectiveness measures, 3) most cases were clinically diagnosed, and TB culture-positive case numbers and TB meningitis case numbers were sparse, and 4) small variations in reported population TB burden could have affected relative risk of exposure for cohorts. Conclusions/Significance All three BCG vaccines evaluated were protective against TB, and prevention effectiveness varied by manufacturer. When setting national immunization policy, consideration should be given to prevention effectiveness of BCG preparations.

Objectives: To evaluate the management and visual outcome of cataract surgery in children. Study design: Descriptive. Material and Methods: This study included one hundred pediatric patients having cataracts over a periodof two year, from Is' January 2005 to 31 st December 2006, at the Department of Ophthalmology, SaiduTeaching Hospital, Saidu Sharif, Swat. Results: Age range was fourteen years and below. Sixty five (65%) patients were males and thirty five (35%) females. Sixty three (63%) patients had congenital or developmental cataracts and thirty seven (37%) had traumatic cataracts. Extracapsular cataract extraction (aspiration) was performed on 150 eyes. Postoperative visual acuity was recordable in 112 eyes. Acorrected visual acuity of 6/18 or better was obtained in50 (44.64%) eyes. Forty one (36.6%) eyes obtained visual acuity of 6/24 to 6/60, while in 21 (18.75%) eyesthe visual acuity remained below 6/60. The most common postoperative complication was development ofthick posterior capsule, which occurred in 51 (34%) eyes and vitreous loss in 10 (6.6%) eyes. Pupil blockglaucoma developed in 4 (2.66%) eyes. No case developed endophthalmitis. Posterior chamber IOL wasimplanted in 9 (6%) eyes. Conclusions: Management of cataracts in children is still a problem and delayed presentation leads to poorvisual outcome. The public should be educated to seek early treatment for childhood cataracts. Paramedicsand doctors should be made aware of the problem and its management. Management of unilateral cataractsis still a difficult problem. Therefore search should continue for better surgical approach and better methodsof correction of aphakia so as to achieve better visual outcome. Key words: Childhood Cataracts, Congenital Cataracts and Traumatic Cataracts.

Objective To identify predictors of fertilization rate in patients of unexplained infertility after intracytoplasmic sperm injection (ICSI). Methods Retrospective analysis of females (282) enrolled in quasi experimental design for ICSI at "Islamabad Clinic Serving Infertile Couples" was carried out from July 2013 till June 2014. Females with unexplained infertility were included, whereas well defined male and female causes of infertility were excluded. Fertilization rate (FR) was calculated as percentage transformation of micro injected oocytes into two pronuclei. Categorical variable of FR defined on the basis of 50% FR grouped females; Group I with FR ≤50% and Group II with FR >50%. The groups were compared in terms of demographic variables, base line hormones and oocyte parameters. Univariate logistic regression was executed to obtain odds ratio with 95% confidence interval to quantify the association of predictors like age, duration of infertility, oocytes parameters, hormones; Estradiol, progesterone, follicle stimulating hormone (FSH), luteinizing hormone, prolactin and cytokines interleukin-Iβ (IL-Iβ) with the FR. Results In our study out of 282 females, 19 (6.73%) were in group I and 263 (93.26%) comprised of Group II. Females with high FR(group II) had low Progesterone and FSH (p=0.04, p=0.02) respectively. Mature oocytes (OR: 0.35; 95% CI 1 - 2.56) and IL-Iβ in follicular phase (OR: 1.04; 95% CI: 0.000- 1.20) were significant positive predictors of FR while peak progesterone and FSH had significant negative effect on it. Conclusion Fertilization of oocytes in females of unexplained infertility depended on maturity of oocytes and optimal amounts of ILI- β released by developing follicles in the follicular phase of stimulation cycles of ICSI.