The use of the articulated total body model as a robot dynamics simulation tool

The Articulated Total Body (ATB) model is a computer sumulation program which was originally developed for the study of aircrew member dynamics during ejection from high-speed aircraft. This model is totally three-dimensional and is based on the rigid body dynamics of coupled systems which use Euler's equations of motion with constraint relations of the type employed in the Lagrange method. In this paper the use of the ATB model as a robot dynamics simulation tool is discussed and various simulations are demonstrated. For this purpose the ATB model has been modified to allow for the application of torques at the joints as functions of state variables of the system. Specifically, the motion of a robotic arm with six revolute articulations with joint torques prescribed as functions of angular displacement and angular velocity are demonstrated. The simulation procedures developed in this work may serve as valuable tools for analyzing robotic mechanisms, dynamic effects, joint load transmissions, feed-back control algorithms employed in the actuator control and end-effector trajectories

Effects of an mHealth intervention for community health workers on maternal and child nutrition and health service delivery in India: protocol for a quasi-experimental mixed-methods evaluation.

INTRODUCTION:Millions of children in India still suffer from poor health and under-nutrition, despite substantial improvement over decades of public health programmes. The Anganwadi centres under the Integrated Child Development Scheme (ICDS) provide a range of health and nutrition services to pregnant women, children <6 years and their mothers. However, major gaps exist in ICDS service delivery. The government is currently strengthening ICDS through an mHealth intervention called Common Application Software (ICDS-CAS) installed on smart phones, with accompanying multilevel data dashboards. This system is intended to be a job aid for frontline workers, supervisors and managers, aims to ensure better service delivery and supervision, and enable real-time monitoring and data-based decision-making. However, there is little to no evidence on the effectiveness of such large-scale mHealth interventions integrated with public health programmes in resource-constrained settings on the service delivery and subsequent health and nutrition outcomes. METHODS AND ANALYSIS:This study uses a village-matched controlled design with repeated cross-sectional surveys to evaluate whether ICDS-CAS can enable more timely and appropriate services to pregnant women, children <12 months and their mothers, compared with the standard ICDS programme. The study will recruit approximately 1500 Anganwadi workers and 6000+ mother-child dyads from 400+ matched-pair villages in Bihar and Madhya Pradesh. The primary outcomes are the proportion of beneficiaries receiving (a) adequate number of home visits and (b) appropriate level of counselling by the Anganwadi workers. Secondary outcomes are related to improvements in other ICDS services, and knowledge and practices of the Anganwadi workers and beneficiaries. ETHICS AND DISSEMINATION:Ethical oversight is provided by the Committee for the Protection of Human Subjects at the University of California at Berkeley, and the Suraksha Independent Ethics Committee in India. The results will be published in peer-reviewed journals and analysis data will be made public. TRIAL REGISTRATION NUMBER:ISRCTN83902145

Magnetic properties of strained multiferroic CoCr2O4\mathrm{CoC}{\mathrm{r}}_{2}{\mathrm{O}}_{4}: A soft x-ray study

Using resonant soft x-ray techniques we follow the magnetic behavior of a strained epitaxial film of CoCr2O4, a type-II multiferroic. The film is [110] oriented, such that both the ferroelectric and ferromagnetic moments can coexist in-plane. X-ray magnetic circular dichroism (XMCD) is used in scattering and in transmission modes to probe the magnetization of Co and Cr separately. The transmission measurements utilized x-ray excited optical luminescence from the substrate. Resonant soft x-ray diffraction (RXD) was used to study the magnetic order of the low temperature phase. The XMCD signals of Co and Cr appear at the same ordering temperature TC≈90K, and are always opposite in sign. The coercive field of the Co and of Cr moments is the same, and is approximately two orders of magnitude higher than in bulk. Through sum rules analysis an enlarged Co2+ orbital moment (mL) is found, which can explain this hardening. The RXD signal of the (q q 0) reflection appears below TS, the same ordering temperature as the conical magnetic structure in bulk, indicating that this phase remains multiferroic under strain. To describe the azimuthal dependence of this reflection, a slight modification is required to the spin model proposed by the conventional Lyons-Kaplan-Dwight-Menyuk theory for magnetic spinels

Study of drug utilization trends in respiratory tract infections in a tertiary care teaching hospital: a retrospective study

Background: Drug utilization studies play crucial role in the health sector and ultimately it provides insight into the efficiency of drug use and results of such research can be used to help to set priorities for the rational use of medicines and allocation of health care budgets. Respiratory tract infections (RTIs) contributing to significant mortality and morbidity of populations especially in developing countries like India. Polypharmacy and irrational prescription are significant negative fallouts in treatment of RTIs. Keeping in view of this, our study was undertaken to analyze the drug utilization pattern of RTIs.Methods: The study was conducted at Gandhi Hospital, after obtaining permission from the Institutional Ethics Committee. We have collected data of 600 case records of the patients diagnosed with respiratory tract infection and evaluated for prescribing patterns in consonance with WHO indicators.Results: Out of the total case records 348 (58%) were of male patients and 252 (42%) of female patients. Age wise distribution was done; 79 (13.16%) 0-15 years, 46 (7.67%) 16-30 years, 123 (20.50%) 31-45 years, 194 (32.33%) 46-60 years and 158 (26.33%) patients belongs to >60 years of age group respectively. A total of 4682 drugs were prescribed, 2468 (52.71%) antibiotics, 768 (16.4%) bronchodilators, 581 (12.4%) corticosteroids, 323 (6.89%) antacids, 542 (11.57%) in miscellaneous category respectively. With regard to formulations 2463 (52.60%) oral, 1463 (31.24%) injectable and 756 (16.14%) inhalational drugs were prescribed. Numbers of Fixed dose combinations were 712 (15.20%). 7.8 drugs were prescribed per prescription. 2493 (53.24%) drugs were prescribed from National Essential Medicine List. 4168 (89.02%) drugs were prescribed by their brand names.Conclusions: Prescription of drugs with branded names, Irrational prescribing, poly pharmacy were observed in our study. So there is an urgent need for creating awareness among the health care professionals regarding rational prescription by using data from from drug utilization studies.

Hierarchical Neurocontroller Architecture for Robotic Manipulation

A hierarchical neurocontroller architecture consisting of two artificial neural network systems for the manipulation of a robotic arm is presented. The higher-level network system participates in the delineation of the robot arm workspace and coordinates transformation and the motion decision-making process. The lower-level network provides the correct sequence of control actions. A straightforward example illustrates the architecture\u27\u27s capabilities, including speed, adaptability, and computational efficienc

Intelligent Control of a Robotic Arm Using Hierarchical Neural Network Systems

Two artificial neural network systems are considered in a hierarchical fashion to plan the trajectory and control of a robotic arm. At the higher level of the hierarchy the neural system consists of four networks: a restricted Coulomb energy network to delineate the robot arm workspace; two standard backpropagation (BP) networks for coordinates transformation; and a fourth network which also uses BP and participates in the trajectory planning by cooperating with other knowledge sources. The control emulation process which is developed using a second neural system at a lower hierarchical level provides the correct sequence of control actions. An example is presented to illustrate the capabilities of the developed architectures

Identifying quantitative imaging features of posterior fossa syndrome in longitudinal MRI

Up to 25% of children who undergo brain tumor resection surgery in the posterior fossa develop posterior fossa syndrome (PFS). This syndrome is characterized by mutism and disturbance in speech. Our hypothesis is that there is a correlation between PFS and the occurrence of hypertrophic olivary degeneration (HOD) in structures within the posterior fossa, known as the inferior olivary nuclei (ION). HOD is exhibited as an increase in size and intensity of the ION on an MR image. Longitudinal MRI datasets of 28 patients were acquired consisting of pre-, intra-, and postoperative scans. A semiautomated segmentation process was used to segment the ION on each MR image. A full set of imaging features describing the first- and second-order statistics and size of the ION were extracted for each image. Feature selection techniques were used to identify the most relevant features among the MRI features, demographics, and data based on neuroradiological assessment. A support vector machine was used to analyze the discriminative features selected by a generative k-nearest neighbor algorithm. The results indicate the presence of hyperintensity in the left ION as the most diagnostically relevant feature, providing a statistically significant improvement in the classification of patients (p=0.01) when using this feature alone

Fully-automated identification of imaging biomarkers for post-operative cerebellar mutism syndrome using longitudinal paediatric MRI

Post-operative cerebellar mutism syndrome (POPCMS) in children is a post- surgical complication which occurs following the resection of tumors within the brain stem and cerebellum. High resolution brain magnetic resonance (MR) images acquired at multiple time points across a patient’s treatment allow the quantification of localized changes caused by the progression of this syndrome. However, MR images are not necessarily acquired at regular intervals throughout treatment and are often not volumetric. This restricts the analysis to 2D space and causes difficulty in intra- and inter-subject comparison. To address these challenges, we have developed an automated image processing and analysis pipeline. Multi-slice 2D MR image slices are interpolated in space and time to produce a 4D volumetric MR image dataset providing a longitudinal representation of the cerebellum and brain stem at specific time points across treatment. The deformations within the brain over time are represented using a novel metric known as the Jacobian of deformations determinant. This metric, together with the changing grey-level intensity of areas within the brain over time, are analyzed using machine learning techniques in order to identify biomarkers that correspond with the development of POPCMS following tumor resection. This study makes use of a fully automated approach which is not hypothesis-driven. As a result, we were able to automatically detect six potential biomarkers that are related to the development of POPCMS following tumor resection in the posterior fossa

Quantitative measurement of blood flow in paediatric brain tumours. A comparative study of dynamic susceptibility contrast and multi-timepoint arterial spin-labelled MRI

OBJECTIVE: Arterial spin-labelling (ASL) MRI uses intrinsic blood water to quantify the cerebral blood flow (CBF), removing the need for the injection of a gadolinium-based contrast agent used for conventional perfusion imaging such as dynamic susceptibility contrast (DSC). Owing to the non-invasive nature of the technique, ASL is an attractive option for use in paediatric patients. This work compared DSC and multi-timepoint ASL measures of CBF in paediatric brain tumours. METHODS: Patients (n = 23; 20 low-grade tumours and 3 high-grade tumours) had DSC and multi-timepoint ASL with and without vascular crushers (VC). VC removes the contribution from larger vessel blood flow. Mean perfusion metrics were extracted from control and T(1)-enhanced tumour regions of interest (ROIs): arterial arrival time (AAT) and CBF from the ASL images with and without VC, relative cerebral blood flow (rCBF), relative cerebral blood volume, delay time (DT) and mean transit time (MTT) from the DSC images. RESULTS: Significant correlations existed for: AAT and DT (r = 0.77, p = 0.0002) and CBF and rCBF (r = 0.56, p = 0.02) in control ROIs for ASL-noVC. No significant correlations existed between DSC and ASL measures in the tumour region. Significant differences between control and tumour ROI were found for MTT (p < 0.001) and rCBF (p < 0.005) measures. CONCLUSION: Significant correlations between ASL-noVC and DSC measures in the normal brain suggest that DSC is most sensitive to macrovascular blood flow. The absence of significant correlations within the tumour ROI suggests that ASL is sensitive to different physiological mechanisms compared with DSC measures. ADVANCES IN KNOWLEDGE: ASL provides information which is comparable with that of DSC in healthy tissues, but appears to reflect a different physiology in tumour tissues

On the Minimum Achievable Age of Information for General Service-Time Distributions

There is a growing interest in analysing the freshness of data in networked systems. Age of Information (AoI) has emerged as a popular metric to quantify this freshness at a given destination. There has been a significant research effort in optimizing this metric in communication and networking systems under different settings. In contrast to previous works, we are interested in a fundamental question, what is the minimum achievable AoI in any single-server-single-source queuing system for a given service-time distribution? To address this question, we study a problem of optimizing AoI under service preemptions. Our main result is on the characterization of the minimum achievable average peak AoI (PAoI). We obtain this result by showing that a fixed-threshold policy is optimal in the set of all randomized-threshold causal policies. We use the characterization to provide necessary and sufficient conditions for the service-time distributions under which preemptions are beneficial