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1.
Sensors (Basel) ; 19(13)2019 Jul 07.
Article in English | MEDLINE | ID: mdl-31284648

ABSTRACT

Complex environments pose great challenges for autonomous mobile robot navigation. In this study, we address the problem of autonomous navigation in 3D environments with staircases and slopes. An integrated system for safe mobile robot navigation in 3D complex environments is presented and both the perception and navigation capabilities are incorporated into the modular and reusable framework. Firstly, to distinguish the slope from the staircase in the environment, the robot builds a 3D OctoMap of the environment with a novel Simultaneously Localization and Mapping (SLAM) framework using the information of wheel odometry, a 2D laser scanner, and an RGB-D camera. Then, we introduce the traversable map, which is generated by the multi-layer 2D maps extracted from the 3D OctoMap. This traversable map serves as the input for autonomous navigation when the robot faces slopes and staircases. Moreover, to enable robust robot navigation in 3D environments, a novel camera re-localization method based on regression forest towards stable 3D localization is incorporated into this framework. In addition, we utilize a variable step size Rapidly-exploring Random Tree (RRT) method which can adjust the exploring step size automatically without tuning this parameter manually according to the environment, so that the navigation efficiency is improved. The experiments are conducted in different kinds of environments and the output results demonstrate that the proposed system enables the robot to navigate efficiently and robustly in complex 3D environments.

2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 1809-1812, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30440746

ABSTRACT

In this paper, a novel energy-based signal, the removal energy density $e_{b}$, is proposed as the detecting signal to determine the breakthrough instances in bone drilling based on the energy approach during the process. The proposed signal is derived from the energy conversion and conservation in drilling process. And the relationship between the signal and the drilling parameter, e.g., drilling speed, feed rate and drill bit radius, is derived. Recursive least square with time forgetting factor is used to estimate $e_{b}$ from the drilling parameters and drilling torque information. Unlike the traditional force profile, this proposed signal profile is similar under different drilling parameters including drilling speed and feed rate, hence reducing the difficulty in setting a threshold for the detection. Experiment on porcine bone is performed. The results show that the proposed signal profile is more consistent than the commonly used force profile, verifying the effectiveness of the proposed method.


Subject(s)
Bone and Bones , Mechanical Phenomena , Animals , Swine , Torque
3.
J Med Chem ; 57(12): 5258-69, 2014 Jun 26.
Article in English | MEDLINE | ID: mdl-24878222

ABSTRACT

A series of 4-substituted pyrimido[4,5-d]azepines that are potent, selective 5-HT2C receptor partial agonists is described. A rational medicinal chemistry design strategy to deliver CNS penetration coupled with SAR-based optimization of selectivity and agonist potency provided compounds with the desired balance of preclinical properties. Lead compounds 17 (PF-4479745) and 18 (PF-4522654) displayed robust pharmacology in a preclinical canine model of stress urinary incontinence (SUI) and no measurable functional agonism at the key selectivity targets 5-HT2A and 5-HT2B in relevant tissue-based assay systems. Utilizing recent advances in the structural biology of GPCRs, homology modeling has been carried out to rationalize binding and agonist efficacy of these compounds.


Subject(s)
Azepines/chemistry , Central Nervous System Agents/chemistry , Pyrimidines/chemistry , Receptor, Serotonin, 5-HT2A/metabolism , Receptor, Serotonin, 5-HT2B/metabolism , Receptor, Serotonin, 5-HT2C/metabolism , Serotonin 5-HT2 Receptor Agonists/chemistry , Animals , Azepines/chemical synthesis , Azepines/pharmacology , Blood-Brain Barrier/metabolism , CHO Cells , Central Nervous System Agents/chemical synthesis , Central Nervous System Agents/pharmacology , Cricetulus , Dogs , Drug Design , Humans , Madin Darby Canine Kidney Cells , Permeability , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Serotonin 5-HT2 Receptor Agonists/chemical synthesis , Serotonin 5-HT2 Receptor Agonists/pharmacology , Structure-Activity Relationship , Urinary Incontinence, Stress/drug therapy
4.
J Struct Biol ; 186(1): 1-7, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24607413

ABSTRACT

Cryo-electron microscopy is an increasingly popular tool for studying the structure and dynamics of biological macromolecules at high resolution. A crucial step in automating single-particle reconstruction of a biological sample is the selection of particle images from a micrograph. We present a novel algorithm for selecting particle images in low-contrast conditions; it proves more effective than the human eye on close-to-focus micrographs, yielding improved or comparable resolution in reconstructions of two macromolecular complexes.


Subject(s)
Cryoelectron Microscopy/methods , Imaging, Three-Dimensional , Artificial Intelligence , Bacterial Proteins/ultrastructure , Escherichia coli , Ribosome Subunits, Large, Bacterial/ultrastructure , Ribosome Subunits, Small, Bacterial/ultrastructure , Software , Thermus thermophilus , Vacuolar Proton-Translocating ATPases/ultrastructure
5.
Clin Oral Implants Res ; 24(3): 297-304, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22092589

ABSTRACT

OBJECTIVES: To conduct a randomised controlled trial to evaluate the short-term clinical and radiographic efficacy of the NobelActive™ system and to evaluate the relative importance of achieving primary stability at placement. MATERIALS AND METHODS: A total of 32 subjects were recruited and, using a split-mouth design, the NobelActive(TM) implant was compared with a contralaterally matched Brånemark implant. Both implants were placed in a single surgical procedure into healed sites using a one-stage protocol and reviewed at monthly intervals. NobelActive(TM) implants were functionally loaded with provisional restorations at 1 month and all implants were restored with final crowns 3 months post-implant placement. The implant was assessed using peak insertion torque values, resonance frequency analysis (RFA), clinical parameters, digital subtraction radiography, and cone beam computed tomography. RESULTS: The insertion torque was significantly greater for the NobelActive(TM) implant group (P = 0.02), although no observable difference in RFA values were found. Preliminary results of 6 months follow-up suggest comparable clinical and radiographic healing responses between the test and control implants. Within the limits of the sample population, the survival rates were lower with the test implants, although this difference was not statistically significant. CONCLUSIONS: The NobelActive(TM) implant system requires higher insertion torques and can also achieve greater primary stability compared with a control implant system. Short-term survival and marginal bone levels of NobelActive(TM) and control implants are comparable, although the NobelActive(TM) implant system appeared to be more technique-sensitive.


Subject(s)
Dental Implants , Dental Prosthesis Design , Immediate Dental Implant Loading , Jaw, Edentulous, Partially/rehabilitation , Bone Density , Cone-Beam Computed Tomography , Crowns , Female , Humans , Jaw, Edentulous, Partially/diagnostic imaging , Male , Mandible/diagnostic imaging , Mandible/surgery , Middle Aged , Postoperative Complications/diagnostic imaging , Prospective Studies , Radiography, Dental, Digital , Torque , Treatment Outcome
6.
Bioorg Med Chem Lett ; 19(17): 4999-5003, 2009 Sep 01.
Article in English | MEDLINE | ID: mdl-19646865

ABSTRACT

A range of heterocycle fused azepines were synthesized in order to find a CNS penetrant, selective 5-HT(2C) agonist for the treatment of incontinence. The pyridazo-azepines such as compound 11 were shown to be potent 5-HT(2C) agonists and have potential for CNS penetration and good in vitro ADME properties but lacked selectivity against 5-HT(2B). Fusing a further heterocycle gave the selective triazolopyrimido-azepines. An example of this series, compound 36, was shown to be potent, selective, metabolically stable in vitro and efficacious in an in vivo model of stress urinary incontinence.


Subject(s)
Azepines/chemistry , Pyrimidines/chemistry , Serotonin 5-HT2 Receptor Agonists , Serotonin Receptor Agonists/chemistry , Urinary Incontinence/drug therapy , Animals , Azepines/chemical synthesis , Azepines/pharmacology , CHO Cells , Cell Line , Cricetinae , Cricetulus , Dogs , Drug Discovery , Humans , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Receptor, Serotonin, 5-HT2B/metabolism , Receptor, Serotonin, 5-HT2C/metabolism , Recombinant Proteins/agonists , Recombinant Proteins/metabolism , Serotonin Receptor Agonists/chemical synthesis , Serotonin Receptor Agonists/pharmacology , Transfection
7.
Br J Nurs ; 18(12): 740-4, 2009.
Article in English | MEDLINE | ID: mdl-19543161

ABSTRACT

This project work is an illustration of how nurses can take a leading role in championing patient care. A small group of mental health nurses in a London Trust embarked on 'getting the fundamentals right' in their quest to improve care given to patients. A working group was formed to take this idea forward: The Essence of Care Steering Group. The group uses the Essence of Care benchmarking principles as a base, and an integral part of clinical governance as a guide. It takes a structured approach to sharing and comparing practice, enabling it to identify best practice and to develop action plans to remedy poor practice. Success is seen in the improvements in the quality and care experience of patients, carers and staff at local levels. Common standards in care across the service areas can be achieved and care can be measured in a more structured way across the service areas with easier, more constructive and meaningful sharing of information and skills. Staff morale is also enhanced.


Subject(s)
Nursing , Patient Care , Benchmarking , London
8.
AMIA Annu Symp Proc ; : 971, 2008 Nov 06.
Article in English | MEDLINE | ID: mdl-18999212

ABSTRACT

We present an observational tool to capture computer usage patterns during rounds to inform designs of information and communication technology to support clinical discourse during rounds. The tool captures choreography and logistics of information exchanges supported by clinical information systems during rounds. We developed the tool as part of an ongoing video-recording study of communication to under-stand how, when, and why computers are used during multidisciplinary clinical rounds.


Subject(s)
Computer-Assisted Instruction/methods , Information Dissemination/methods , Internship and Residency/methods , Internship and Residency/organization & administration , Medical History Taking/methods , Software , User-Computer Interface , Maryland
9.
AMIA Annu Symp Proc ; : 980, 2008 Nov 06.
Article in English | MEDLINE | ID: mdl-18998900

ABSTRACT

Continuous recorded in-flight vital signs monitoring and life-saving interventions linked to outcomes may provide better understanding of pre-hospital triage, care management and patient responses during the 'golden hour' of trauma care. Evaluation of 157 patients' vital signs data collected from our statewide network has identified episodes of physiological decompensation which holds promise for creation of new triage algorithms and enhanced trauma center preparedness.


Subject(s)
Air Ambulances , Decision Support Systems, Clinical , Emergency Medical Services/methods , Monitoring, Physiologic/methods , Triage/methods , Vital Signs , Wounds and Injuries/diagnosis , Computer Systems , Heart Failure/diagnosis , Heart Failure/prevention & control , Humans , Maryland , Reproducibility of Results , Sensitivity and Specificity , Wounds and Injuries/prevention & control
10.
Nurs Outlook ; 55(6): 282-288, 2007.
Article in English | MEDLINE | ID: mdl-18061012

ABSTRACT

Healthcare information systems (HIS) play a vital role in quality of care and the organization's daily operations. Consequently, increasing numbers of clinicians have been involved in HIS implementation, particularly for clinical information systems (CIS). Implementation of these systems is a major organizational investment, and its outcomes must be assessed. The purpose of this article is to provide clinicians and frontline informaticians with a practical guide to assess these outcomes, focusing on outcome variables, assessment methods, and timing of assessment. Based on in-depth literature reviews and their empirical experiences, the authors identified 3 frequently used outcomes: user satisfaction, clinical outcomes, and financial impact. These outcomes have been assessed employing various methods, including randomized controlled trials, pre- and post-test studies, time and motion studies, surveys, and user testing. The timing for outcomes assessments varied depending on several factors, such as learning curves or patients conditions. In conclusion, outcomes assessment is essential for the success of healthcare information technology, and the CIS implementation team members must be prepared to conduct and/or facilitate these studies.


Subject(s)
Information Systems/organization & administration , Medical Order Entry Systems/organization & administration , Medical Records Systems, Computerized/organization & administration , Outcome Assessment, Health Care/organization & administration , Attitude of Health Personnel , Attitude to Computers , Clinical Competence , Confounding Factors, Epidemiologic , Cost-Benefit Analysis , Expert Systems , Hospital Information Systems , Humans , Investments/economics , Nursing Informatics , Nursing Research , Program Evaluation , Qualitative Research , Randomized Controlled Trials as Topic , Research Design , Surveys and Questionnaires , Time and Motion Studies , User-Computer Interface
11.
Anesth Analg ; 105(6): 1701-10, table of contents, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18042870

ABSTRACT

BACKGROUND: An anesthesia department implemented scheduling of anesthetics outside of operating rooms (non-OR) by clerks and nurses from other departments using its hospital's enterprise-wide scheduling system. METHODS: Observational studies chronicled the change over 2 yr as non-OR time was allocated by specialty, and nonanesthesia clerks and nurses scheduled anesthesia teams. Experimental studies investigated how tabular and graphical displays affected the scheduling of milestones (e.g., NPO times) and appointments before anesthetics. RESULTS: Anesthetics performed in allocated time increased progressively from 0% to 75%. Scheduling of anesthetics by nonanesthesia clerks and nurses increased progressively from 0% to 77%. Consistency of patient instructions was improved. The quality of resulting schedules was good. Implementation was not associated with worsening of multiple operational measures of performance such as cancellation rates, turnover times, or complaints. However, schedulers struggled to understand fasting and arrival times of patients, despite using a web site with statistically generated values in tabular formats. Experiments revealed that people ignored their knowledge that anesthetics can start earlier than scheduled. Participants made good decisions with both tabular and graphical displays when scheduling appointments preceding anesthesia. CONCLUSIONS: Enterprise-wide scheduling can coordinate anesthetics with other appointments on the same date and improve consistency and accuracy of patient instructions customized to the probability of an anesthetic starting early. The usefulness of implementation depends on the value in having more patient-centered care and/or in having patients arrive just in time for non-OR anesthesia, surgery, or regional block placement (e.g., at facilities with limited physical space).


Subject(s)
Anesthesia Department, Hospital/organization & administration , Anesthesia , Appointments and Schedules , Operating Rooms/organization & administration , Humans , Operating Room Information Systems/organization & administration , Organization and Administration
12.
Br J Nurs ; 16(1): 39-42, 44-6, 2007.
Article in English | MEDLINE | ID: mdl-17353834

ABSTRACT

This study aims to explore the value and meaning of a psychodynamic work discussion for mental health nurses, and its potential as an approach in staff clinical supervision. Data were generated by using a focus group with a purposive sample of six mental health nurses, and analysed by the 'collapsing of data' from labels to form categories and formulate themes. The findings suggest that staff emotion generated from clinical work is dealt with in many personal ways though rarely in clinical supervision. Although the idea of a work discussion group is not readily known among the focus group, staff appear to be open to its potential to provide a helpful emotional perspective. Education in the form of an introduction and exposure to some basic psychodynamic ideas could provide the first step towards unlocking its potential. Sharing personal experiences of an emotional nature within a safe, secure environment seems significant in this education process.


Subject(s)
Attitude of Health Personnel , Clinical Competence , Focus Groups , Nursing Staff/psychology , Nursing, Supervisory/organization & administration , Psychiatric Nursing/organization & administration , Adaptation, Psychological , Data Collection , Data Interpretation, Statistical , Education, Nursing, Continuing/methods , Emotions , Focus Groups/methods , Health Knowledge, Attitudes, Practice , Humans , Interprofessional Relations , Models, Nursing , Nurse's Role/psychology , Nursing Methodology Research/methods , Nursing Staff/education , Nursing Staff/organization & administration , Psychiatric Nursing/education , Psychoanalytic Interpretation , Qualitative Research , Research Design , Social Support , Workplace/psychology
13.
AMIA Annu Symp Proc ; : 1160, 2007 Oct 11.
Article in English | MEDLINE | ID: mdl-18694256

ABSTRACT

We developed a conceptual design of a mobile computing platform to support multi-disciplinary rounds in intensive care units.


Subject(s)
Intensive Care Units/organization & administration , Medical Informatics Applications , Patient Care Team/organization & administration , Communication , Computers , Humans
14.
AMIA Annu Symp Proc ; : 329-33, 2007 Oct 11.
Article in English | MEDLINE | ID: mdl-18693852

ABSTRACT

Multi-disciplinary rounds are a forum for communication and sense-making, and they play a critical role in intensive care to ensure care coordination across specialties and providers. Increased availability of clinical information through computers has made it possible to provide support during rounds. We conducted an observation study to determine ways in which computers may be used during rounds, when users are under time pressure in accessing and manipulating clinical data. A total of fifteen hours of rounds in a pediatric intensive care unit for 47 patients were observed. Factors influencing information transfer during rounds were characterized in three areas: physical, social and cognitive, and supporting artifacts. Based on these factors we developed a set of design guidelines for computerized supporting tools. An example guideline suggests digital capture of handwritten notes. These guidelines developed may help guide future systems development, thus leveraging the power of computing during the critical moments of multi-disciplinary rounds.


Subject(s)
Hospital Information Systems , Intensive Care Units, Pediatric/organization & administration , Patient Care Management/organization & administration , Point-of-Care Systems , Communication , Critical Care , Decision Support Systems, Clinical , Humans , Observation
15.
Surg Innov ; 13(2): 129-35, 2006 Jun.
Article in English | MEDLINE | ID: mdl-17012154

ABSTRACT

One of the major challenges for day-of-surgery operating room coordination is accurate and timely situation awareness. Distributed and secure real-time status information is key to addressing these challenges. This article reports on the design and implementation of a passive status monitoring system in a 19-room surgical suite of a major academic medical center. Key design requirements considered included integrated real-time operating room status display, access control, security, and network impact. The system used live operating room video images and patient vital signs obtained through monitors to automatically update events and operating room status. Images were presented on a "need-to-know" basis, and access was controlled by identification badge authorization. The system delivered reliable real-time operating room images and status with acceptable network impact. Operating room status was visualized at 4 separate locations and was used continuously by clinicians and operating room service providers to coordinate operating room activities.


Subject(s)
Computer Communication Networks/organization & administration , Operating Room Information Systems/organization & administration , Operating Rooms/organization & administration , Computer Terminals , Humans
16.
AMIA Annu Symp Proc ; : 951, 2006.
Article in English | MEDLINE | ID: mdl-17238570

ABSTRACT

This poster describes the design and evaluation of an International Video Teleconference (iVTC) system for orthopedic trauma case studies. Three medical facilities in the United States and one in Australia participated in monthly sessions where past and ongoing military and civilian cases were discussed. Participant feedback indicated that iVTC fully met their expectations as an educational tool and that remote participation did not adversely impact their ability to engage in discussion.


Subject(s)
Education, Distance , Orthopedics/education , Traumatology/education , Videoconferencing , Consumer Behavior , Data Collection , Humans
17.
Anesth Analg ; 101(3): 823-829, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16115998

ABSTRACT

We developed an algorithm for processing networked vital signs (VS) to remotely identify in real-time when a patient enters and leaves a given operating room (OR). The algorithm addresses two types of mismatches between OR occupancy and VS: a patient is in the OR but no VS are available (e.g., patient is being hooked up), and no patient is in the OR but artifactual VS are present (e.g., because of staff handling of sensors). The algorithm was developed with data from 7 consecutive days (122 cases) in a 6 OR trauma center. The algorithm was then tested on data from another 7 consecutive days (98 cases), against patient in- and out-times captured by OR surveillance videos. When pulse oximetry, electrocardiogram, and temperature readings were used, OR occupancy was correctly identified 96% (95% confidence interval [CI] 95%-97%) and OR vacancy >99% of the time. Identified patient in- and out-times were accurate within 4.9 min (CI 4.2-5.7) and 2.8 min (CI 2.3-3.5), respectively, and were not different in accuracy from times reported by staff on OR records. The algorithm's usefulness was demonstrated partly by its continued operational use. We conclude that VS can be processed to accurately report OR occupancy in real-time.


Subject(s)
Algorithms , Monitoring, Intraoperative/statistics & numerical data , Operating Rooms/organization & administration , Operating Rooms/statistics & numerical data , Computer Systems , Data Interpretation, Statistical , Software
18.
Org Biomol Chem ; 3(8): 1365-8, 2005 Apr 21.
Article in English | MEDLINE | ID: mdl-15827628

ABSTRACT

The title reagent engaged in the modified Julia olefination with aldehydes under mild reaction conditions (DBU, CH(2)Cl(2), rt or -78 degrees C) to yield alpha,beta-unsaturated esters; aryl aldehydes and aliphatic aldehydes possessing significant chain branching elements gave trans alkene products with high stereoselectivity (E : Z up to >98 : 2), while straight chain aliphatic aldehydes gave cis products preferentially (Z : E up to 92 : 8).


Subject(s)
Acetates/chemistry , Aldehydes/chemistry , Benzothiazoles/chemistry , Esters/chemical synthesis , Sulfones/chemistry , Alkenes/chemistry , Butyrates/chemistry , Esters/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Nitro Compounds/chemistry , Stereoisomerism
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