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1.
Sci Rep ; 12(1): 21004, 2022 12 05.
Article in English | MEDLINE | ID: mdl-36470894

ABSTRACT

Because many vessels use the Automatic Identification System (AIS) to broadcast GPS positions, recent advances in satellite technology have enabled us to map global fishing activity. Understanding of human activity at sea, however, is limited because an unknown number of vessels do not broadcast AIS. Those vessels can be detected by satellite-based Synthetic Aperture Radar (SAR) imagery, but this technology has not yet been deployed at scale to estimate the size of fleets in the open ocean. Here we combine SAR and AIS for large-scale open ocean monitoring, developing methods to match vessels with AIS to vessels detected with SAR and estimate the number of non-broadcasting vessels. We reveal that, between September 2019 and January 2020, non-broadcasting vessels accounted for about 35% of the longline activity north of Madagascar and 10% of activity near French Polynesia and Kiribati's Line Islands. We further demonstrate that this method could monitor half of the global longline activity with about 70 SAR images per week, allowing us to track human activity across the oceans.


Subject(s)
Fisheries , Radar , Humans , Oceans and Seas , Satellite Imagery , Madagascar
2.
Gait Posture ; 40(1): 11-9, 2014.
Article in English | MEDLINE | ID: mdl-24768525

ABSTRACT

The proliferation of miniaturized electronics has fueled a shift toward wearable sensors and feedback devices for the mass population. Quantified self and other similar movements involving wearable systems have gained recent interest. However, it is unclear what the clinical impact of these enabling technologies is on human gait. The purpose of this review is to assess clinical applications of wearable sensing and feedback for human gait and to identify areas of future research. Four electronic databases were searched to find articles employing wearable sensing or feedback for movements of the foot, ankle, shank, thigh, hip, pelvis, and trunk during gait. We retrieved 76 articles that met the inclusion criteria and identified four common clinical applications: (1) identifying movement disorders, (2) assessing surgical outcomes, (3) improving walking stability, and (4) reducing joint loading. Characteristics of knee and trunk motion were the most frequent gait parameters for both wearable sensing and wearable feedback. Most articles performed testing on healthy subjects, and the most prevalent patient populations were osteoarthritis, vestibular loss, Parkinson's disease, and post-stroke hemiplegia. The most widely used wearable sensors were inertial measurement units (accelerometer and gyroscope packaged together) and goniometers. Haptic (touch) and auditory were the most common feedback sensations. This review highlights the current state of the literature and demonstrates substantial potential clinical benefits of wearable sensing and feedback. Future research should focus on wearable sensing and feedback in patient populations, in natural human environments outside the laboratory such as at home or work, and on continuous, long-term monitoring and intervention.


Subject(s)
Biofeedback, Psychology/instrumentation , Feedback, Sensory/physiology , Gait/physiology , Monitoring, Ambulatory/instrumentation , Movement Disorders/physiopathology , Movement/physiology , Remote Sensing Technology/instrumentation , Adult , Ankle/physiology , Clothing , Craniocerebral Trauma/physiopathology , Equipment Design , Foot/physiology , Hemiplegia/physiopathology , Humans , Knee/physiology , Leg/physiology , Osteoarthritis/physiopathology , Parkinson Disease/physiopathology , Reference Values , Transducers , Walking/physiology , Weight-Bearing/physiology , Wireless Technology/instrumentation
3.
Ann Biomed Eng ; 41(9): 1939-49, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23604848

ABSTRACT

The purpose of this study was to evaluate a novel instrumented mouthguard as a research device for measuring head impact kinematics. To evaluate kinematic accuracy, laboratory impact testing was performed at sites on the helmet and facemask for determining how closely instrumented mouthguard data matched data from an anthropomorphic test device. Laboratory testing results showed that peak linear acceleration (r (2) = 0.96), peak angular acceleration (r (2) = 0.89), and peak angular velocity (r (2) = 0.98) measurements were highly correlated between the instrumented mouthguard and anthropomorphic test device. Normalized root-mean-square errors for impact time traces were 9.9 ± 4.4% for linear acceleration, 9.7 ± 7.0% for angular acceleration, and 10.4 ± 9.9% for angular velocity. This study demonstrates the potential of an instrumented mouthguard as a research tool for measuring in vivo impacts, which could help uncover the link between head impact kinematics and brain injury in American football.


Subject(s)
Craniocerebral Trauma/prevention & control , Football , Head Protective Devices , Mouth Protectors , Biomechanical Phenomena , Humans
4.
J Orthop Res ; 31(7): 1020-5, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23494804

ABSTRACT

This study examined the influence of a 6-week gait retraining program on the knee adduction moment (KAM) and knee pain and function. Ten subjects with medial compartment knee osteoarthritis and self-reported knee pain participated in weekly gait retraining sessions over 6 weeks. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and a 10-point visual-analog pain scale score were measured at baseline, post-training (end of 6 weeks), and 1 month after training ended. Gait retraining reduced the first peak KAM by 20% (p < 0.01) post-training as a result of a 7° decrease in foot progression angle (i.e., increased internal foot rotation), compared to baseline (p < 0.01). WOMAC pain and function scores were improved at post-training by 29% and 32%, respectively (p < 0.05) and visual-analog pain scale scores improved by two points (p < 0.05). Changes in WOMAC pain and function were approximately 75% larger than the expected placebo effect (p < 0.05). Changes in KAM, foot progression angle, WOMAC pain and function, and visual-analog pain score were retained 1 month after the end of the 6-week training period (p < 0.05). These results show that a 6-week gait retraining program can reduce the KAM and improve symptoms for individuals with medial compartment knee osteoarthritis and knee pain.


Subject(s)
Arthralgia/rehabilitation , Gait/physiology , Knee Joint/physiopathology , Osteoarthritis, Knee/rehabilitation , Physical Therapy Modalities , Range of Motion, Articular/physiology , Aged , Arthralgia/physiopathology , Biomechanical Phenomena/physiology , Female , Humans , Male , Middle Aged , Osteoarthritis, Knee/physiopathology , Pain Measurement , Severity of Illness Index , Treatment Outcome
5.
J Biomech ; 46(1): 122-8, 2013 Jan 04.
Article in English | MEDLINE | ID: mdl-23146322

ABSTRACT

The first peak of the knee adduction moment has been linked to the presence, severity, and progression of medial compartment knee osteoarthritis. The objective of this study was to evaluate toe-in gait (decreased foot progression angle from baseline through internal foot rotation) as a means to reduce the first peak of the knee adduction moment in subjects with medial compartment knee osteoarthritis. Additionally, we examined whether the first peak in the knee adduction moment would cause a concomitant increase in the peak external knee flexion moment, which can eliminate reductions in the medial compartment force that result from lowering the knee adduction moment. We tested the following hypotheses: (a) toe-in gait reduces the first peak of the knee adduction moment, and (b) toe-in gait does not increase the peak external knee flexion moment. Twelve patients with medial compartment knee osteoarthritis first performed baseline walking trials and then toe-in gait trials at their self-selected speed on an instrumented treadmill in a motion capture laboratory. Subjects altered their foot progression angle from baseline to toe-in gait by an average of 5° (p<0.01), which reduced the first peak of the knee adduction moment by an average of 13% (p<0.01). Toe-in gait did not increase the peak external knee flexion moment (p=0.85). The reduced knee adduction moment was accompanied by a medially-shifted knee joint center and a laterally-shifted center of pressure during early stance. These results suggest that toe-in gait may be a promising non-surgical treatment for patients with medial compartment knee osteoarthritis.


Subject(s)
Gait/physiology , Osteoarthritis, Knee/therapy , Walking/physiology , Aged , Biomechanical Phenomena , Female , Foot/physiology , Humans , Male , Middle Aged , Osteoarthritis, Knee/physiopathology , Rotation
6.
PM R ; 4(5 Suppl): S141-4, 2012 May.
Article in English | MEDLINE | ID: mdl-22632693

ABSTRACT

Post-traumatic osteoarthritis (PTOA) is a process resulting from direct forces applied to a joint that cause injury and degenerative changes. An estimated 12% of all symptomatic osteoarthritis (OA) of the hip, knee, and ankle can be attributed to a post-traumatic cause. Neuromuscular prehabilitation is the process of improving neuromuscular function to prevent development of PTOA after an initial traumatic joint injury. Prehabilitation strategies include restoration of normative movement patterns that have been altered as the result of traumatic injury, along with neuromuscular exercises and gait retraining to prevent the development of OA after an injury occurs. A review of the current literature shows that no studies have been performed to evaluate methods of neuromuscular prehabilitation to prevent PTOA after a joint injury. Instead, current research has focused on management strategies after knee injuries, the value of exercise in the management of OA, and neuromuscular exercises after total knee arthroplasty. Recent work in gait retraining that alters knee joint loading holds promise for preventing the development of PTOA after joint trauma. Future research should evaluate methods of neuromuscular prehabilitation strategies in relationship to the outcome of PTOA after joint injury.


Subject(s)
Knee Injuries/complications , Osteoarthritis, Knee/etiology , Osteoarthritis, Knee/prevention & control , Biofeedback, Psychology , Biomechanical Phenomena , Disease Progression , Exercise Therapy , Gait/physiology , Humans , Knee Injuries/physiopathology , Knee Joint/physiopathology , Osteoarthritis, Knee/physiopathology
7.
J Biomech ; 44(8): 1605-9, 2011 May 17.
Article in English | MEDLINE | ID: mdl-21459384

ABSTRACT

The purpose of this study was to evaluate gait retraining for reducing the knee adduction moment. Our primary objective was to determine whether subject-specific altered gaits aimed at reducing the knee adduction moment by 30% or more could be identified and adopted in a single session through haptic (touch) feedback training on multiple kinematic gait parameters. Nine healthy subjects performed gait retraining, in which data-driven models specific to each subject were determined through experimental trials and were used to train novel gaits involving a combination of kinematic changes to the tibia angle, foot progression and trunk sway angles. Wearable haptic devices were used on the back, knee and foot for real-time feedback. All subjects were able to adopt altered gaits requiring simultaneous changes to multiple kinematic parameters and reduced their knee adduction moments by 29-48%. Analysis of single parameter gait training showed that moving the knee medially by increasing tibia angle, increasing trunk sway and toeing in all reduced the first peak of the knee adduction moment with tibia angle changes having the most dramatic effect. These results suggest that individualized data-driven gait retraining may be a viable option for reducing the knee adduction moment as a treatment method for early-stage knee osteoarthritis patients with sufficient sensation, endurance and motor learning capabilities.


Subject(s)
Gait , Knee Joint/anatomy & histology , Knee/anatomy & histology , Walking , Adult , Biomechanical Phenomena , Equipment Design , Female , Humans , Knee Joint/physiology , Male , Models, Anatomic , Osteoarthritis, Knee , Range of Motion, Articular
8.
J Biomech Eng ; 133(4): 041007, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21428681

ABSTRACT

The external knee adduction moment (KAM) measured during gait is an indicator of tibiofemoral joint osteoarthritis progression and various strategies have been proposed to lower it. Gait retraining has been shown to be an effective, noninvasive approach for lowering the KAM. We present a new gait retraining approach in which the KAM is fed back to subjects in real-time during ambulation. A study was conducted in which 16 healthy subjects learned to alter gait patterns to lower the KAM through visual or tactile (vibration) feedback. Participants converged on a comfortable gait in just a few minutes by using the feedback to iterate on various kinematic modifications. All subjects adopted altered gait patterns with lower KAM compared with normal ambulation (average reduction of 20.7%). Tactile and visual feedbacks were equally effective for real-time training, although subjects using tactile feedback took longer to converge on an acceptable gait. This study shows that real-time feedback of the KAM can greatly increase the effectiveness and efficiency of subject-specific gait retraining compared with conventional methods.


Subject(s)
Feedback , Gait/physiology , Knee/physiology , Learning/physiology , Touch/physiology , Vibration , Vision, Ocular/physiology , Adult , Exercise Test , Female , Humans , Kinetics , Knee Joint/physiology , Male , Middle Aged , Time Factors , Weight-Bearing/physiology , Young Adult
9.
Fetal Diagn Ther ; 23(2): 136-9, 2008.
Article in English | MEDLINE | ID: mdl-18046072

ABSTRACT

An abnormal course of the umbilical vein is a rare anomaly. Its association with the congenital absence of the ductus venosus is common. We found 3 cases of an abnormal course of the umbilical vein and an absent ductus venosus. In 2 of these cases, the umbilical vein turned down and continued in the internal iliac vein, and no ductus venosus was found. One of these pregnancies was terminated. From the continued pregnancy a growth-retarded baby was born. At follow-up examinations, mild microcephaly, mildly elevated levels of ammonia, delayed speech and mild muscular hypotonia were found. In the third case, the umbilical vein turned up from the level of umbilical ring and the anterior of the liver above the diaphragma and connected directly into the right atrium. Associated complex congenital heart malformations - transposition of the great arteries, and ventricular septal defect - were diagnosed prenatally. In the umbilical vein from the placenta to the umbilical ring, the flow was low velocity continuous; from the umbilical ring to the right atrium, the flow was biphasic high velocity (90 cm/s). Such an elevated blood flow could be a sign of increased cardiac preload. The long-term neurological follow-up of babies with prenatally diagnosed venous malformations is necessary.


Subject(s)
Fetal Heart/abnormalities , Fetal Heart/diagnostic imaging , Prenatal Diagnosis/methods , Umbilical Veins/abnormalities , Umbilical Veins/diagnostic imaging , Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/diagnostic imaging , Adult , Female , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/diagnostic imaging , Humans , Infant, Newborn , Male , Pregnancy , Ultrasonography
10.
J Environ Sci Health B ; 42(5): 471-80, 2007.
Article in English | MEDLINE | ID: mdl-17562454

ABSTRACT

Fipronil is a phenylpyrazole insecticide used in agricultural and domestic settings for controlling various insect pests in crops, lawns, and residential structures. Fipronil is chiral; however, it is released into the environment as a racemic mixture of two enantiomers. In this study, the acute toxicity of the (S,+) and (R,-) enantiomers and the racemic mixture of fipronil were assessed using Simulium vittatum IS-7 (black fly), Xenopus laevis (African clawed frog), Procambarus clarkii (crayfish), Palaemonetes pugio (grass shrimp), Mercenaria mercenaria (hardshell clam), and Dunaliella tertiolecta (phytoplankton). Results showed that S. vittatum IS-7 was the most sensitive freshwater species to the racemic mixture of fipronil (LC50 = 0.65 microg/L) while P. pugio was the most sensitive marine species (LC50 = 0.32 microg/L). Procambarus clarkii were significantly more sensitive to the (S,+) enantiomer while larval P. pugio were significantly more sensitive to the (R,-) enantiomer. Enantioselective toxicity was not observed in the other organisms tested. Increased mortality and minimal recovery was observed in all species tested for recovery from fipronil exposure. These results indicate that the most toxic isomer of fipronil is organism-specific and that enantioselective toxicity may be more common in crustaceans than in other aquatic organisms.


Subject(s)
Environmental Exposure , Insecticides/toxicity , Pyrazoles/toxicity , Toxicity Tests/methods , Water Pollutants, Chemical/toxicity , Animals , Astacoidea/drug effects , Astacoidea/growth & development , Biological Assay , Bivalvia/drug effects , Bivalvia/growth & development , Ecosystem , Environmental Monitoring , Insecticides/chemistry , Palaemonidae/drug effects , Palaemonidae/growth & development , Phytoplankton/drug effects , Phytoplankton/growth & development , Pyrazoles/chemistry , Simuliidae/drug effects , Simuliidae/growth & development , Species Specificity , Water Pollution, Chemical , Xenopus laevis/growth & development
11.
Fetal Diagn Ther ; 21(2): 198-203, 2006.
Article in English | MEDLINE | ID: mdl-16491003

ABSTRACT

OBJECTIVE: To find connection between the type of congenital heart malformations and twin pregnancies. METHOD: Retrospective analysis of data of fetal cardiology database between 1 January 1996 and 30 November 2003. RESULTS: In single pregnancies 455 and in twin pregnancies 31 severe congenital heart malformations were diagnosed prenatally. In monozygotic twin pregnancies 36% of heart malformations were pulmonary stenosis and 45% endocardial fibroelastosis, which is significantly higher than in single pregnancies. In dizygotic twin pregnancies Ebstein malformation was significantly more frequent than in single pregnancies. With the exception of Ebstein malformation in dichorionic and dizygotic twin pregnancies the cardiac malformations were similar to the ones in single pregnancies. CONCLUSIONS: The twin pregnancy alone can be considered as indication for fetal echocardiography. The type of congenital heart malformations detected in monochorial twin pregnancies was different from those found in single, dizygotic or dichorionic twin pregnancies. Chorionicity seems to be more important than zygosity.


Subject(s)
Heart Defects, Congenital/epidemiology , Twins, Dizygotic , Twins, Monozygotic , Female , Humans , Hungary/epidemiology , Incidence , Placentation , Pregnancy , Prenatal Diagnosis , Retrospective Studies
12.
J Neurosci Methods ; 151(2): 194-9, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16153712

ABSTRACT

A versatile teleoperated robotic system was created as an assessment device for testing upper-extremity motor control adaptation using different control strategies. While many systems display output virtually on a computer monitor, this system was designed to output in three-dimensional physical space. The system accepts haptic force and torque input, and outputs robot end-effector displacements and rotations in three spatial dimensions. Benefits of this system include flexibility to conduct a variety of dissimilar tasks and reality of user feedback in physical space. Two separate experiments validated the teleoperated robotic system. The first experiment tested unimanual human motor control and the second tested bimanual motor control. This teleoperated robotic system can be used as an assessment device to study neuromuscular adaptability via a variety of control strategies providing a new and functional approach to human motor control analysis.


Subject(s)
Biomechanical Phenomena/instrumentation , Man-Machine Systems , Motor Skills/physiology , Movement/physiology , Robotics/instrumentation , Touch/physiology , User-Computer Interface , Arm/physiology , Biomechanical Phenomena/methods , Computer Systems , Equipment Design , Equipment Failure Analysis , Feedback/physiology , Humans , Physical Stimulation/instrumentation , Physical Stimulation/methods , Robotics/methods , Software , Task Performance and Analysis
13.
Eur J Gynaecol Oncol ; 24(6): 517-22, 2003.
Article in English | MEDLINE | ID: mdl-14658593

ABSTRACT

OBJECTIVE: Our clinical practice for FIGO Stage II endometrial cancer consists of Wertheim's radical hysterectomy as first choice of treatment. The evaluation of patients is based on D&C. The accuracy of this preoperative staging method is examined here. METHODS: Twenty-nine patients with endometrial cancer with suspected cervical involvement (FIGO Stage II) based on endocervical curettage underwent Wertheim's radical hysterectomy between January 1, 1989 and December 31, 2001 at the Gynaecological Department of the National Institute of Cancer, Budapest, Hungary. In all cases surgico-pathological staging was performed to examine the accuracy of preoperative D&C and to find out whether radical surgery was necessary in all patients and how the preoperative evaluation of patients should be improved. RESULTS: Out of 29 patients who underwent Wertheim's hysterectomy the pathological examination found primary cervical cancer in two patients. These two patients were eliminated from further evaluation. Out of the remaining 27 patients only eight (29.6%) had cervical involvement of endometrial cancer documented by a pathologic review on the hysterectomy specimen. Extrauterine disease was documented in one of the patients with cervical infiltration (1/8) and in one in the cervix-negative group (1/19). Ovarian spread was found in the first case and ovarian infiltration with penetration of the tumour into the parametric tissue in the second case. According to the FIGO classification 18 (66.6%) patients had less extensive disease and two (7.4%) had more extensive disease. Only 26% of the patients (7/27) had surgical findings consistent with the Stage II disease. CONCLUSION: We can conclude that "overtreatment" seems to have occurred in 19 patients, whose cervical infiltration by endometrial cancer could not be proved by pathological staging. It can also be assessed that understaging took place in two cases, which can be explained by two reasons; we did not make use of preoperative imaging techniques since US was applied in six patients, CT in 16 and the most accurate, MRI, on three patients only. The other possible reason, which can point out the bad efficacy of the imaging techniques as well, could be that a major part of the patients received preoperative AL treatment, which could also have influenced the cervical progression. This is possible, but has not been proved. The difference in the number of cervical infiltrations in the group of patients who received preoperative radiotherapy and in the group where they did not, is not significant (p = 0.9742), and infiltration of the endometrium was present in all cases. In the future, proper selection of imaging modalities can improve the staging of gynaecological disorders and preclude unnecessary procedures. In endometrial cancer cases US, especially with the use of TVUS, is often considered to be the primary imaging approach. However, in patients where ultrasound is suboptimal, where there is a large tumour present or the result of imaging studies will directly influence the choice of therapy and guide therapy planning then the higher accuracy of MRI warrants its use. CT is of use in the later stages of disease; differentiation between Stage I and II is difficult and CT is limited in the assessment of myometrial invasion.


Subject(s)
Adenocarcinoma/diagnosis , Diagnostic Imaging/standards , Endometrial Neoplasms/diagnosis , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Diagnostic Imaging/methods , Dilatation , Endometrial Neoplasms/diagnostic imaging , Endometrial Neoplasms/pathology , Endometrial Neoplasms/surgery , Female , Humans , Hysterectomy , Magnetic Resonance Imaging , Neoplasm Staging/methods , Neoplasm Staging/standards , Predictive Value of Tests , Preoperative Care/methods , Preoperative Care/standards , Tomography, X-Ray Computed , Ultrasonography/methods
14.
Drug Des Discov ; 11(2): 91-113, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8075303

ABSTRACT

A series of trifluoromethyl-containing analogs of captopril as well as analogs and homologs of enalaprilat were synthesized and evaluated for inhibition of angiotensin converting enzyme (ACE). It was found that direct substitution of trifluoromethyl for methyl produced a very potent captopril analog with an IC50 of 3 x 10(-10) M in vitro. Hydrophobicity and conformational effects of trifluoromethyl group are among the reasons accounting for this activity. Structure-activity relationship is studied based on molecular mechanics calculations using a II-SCF-molecular mechanics program (PIMM) as well as SYBYL molecular mechanics program. It was found that simultaneous incorporation of trifluoromethyl and an indoline residue unexpectedly yielded a less potent captopril analog (IC50 = 8 x 10(-8) M). Enalaprilat analogs derived from replacement of the alanine residue with trifluoronorvaline and trifluoronorleucine residues gave moderately potent compounds (IC50 = 2-6 x 10(-8) M). The structure-activity relationship for these fluoroenalaprilat analogs is discussed in comparison with known analogs.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/chemical synthesis , Hydrocarbons, Fluorinated/chemical synthesis , Angiotensin-Converting Enzyme Inhibitors/chemistry , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Captopril/analogs & derivatives , Captopril/chemistry , Captopril/pharmacology , Crystallography, X-Ray , Drug Design , Enalaprilat/analogs & derivatives , Enalaprilat/chemistry , Enalaprilat/pharmacology , Hydrocarbons, Fluorinated/chemistry , Hydrocarbons, Fluorinated/pharmacology , Structure-Activity Relationship
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