Health Monitoring (health + monitoring)

Distribution by Scientific Domains

Kinds of Health Monitoring

  • structural health monitoring


  • Selected Abstracts


    A New Approach for Health Monitoring of Structures: Terrestrial Laser Scanning

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2007
    H. S. Park
    Three-dimensional (3D) coordinates of a target structure acquired using TLS can have maximum errors of about 10 mm, which is insufficient for the purpose of health monitoring of structures. A displacement measurement model is presented to improve the accuracy of the measurement. The model is tested experimentally on a simply supported steel beam. Measurements were made using three different techniques: (1) linear variable displacement transducers (LVDTs), (2) electric strain gages, and (3) a long gage fiber optic sensor. The maximum deflections estimated by the TLS model are less than 1 mm and within 1.6% of those measured directly by LVDT. Although GPS methods allow measurement of displacements only at the GPS receiver antenna location, the proposed TLS method allows measurement of the entire building's or bridge's deformed shape, and thus a realistic solution for monitoring structures at both structure and member level. Furthermore, it can be used to create a 3D finite element model of a structural member or the entire structure at any instance of time automatically. Through periodic measurements of deformations of a structure or a structural member and performing inverse structural analyses with the measured 3D displacements, the health of the structure can be monitored continuously. [source]


    Health Monitoring of Rehabilitated Concrete Bridges Using Distributed Optical Fiber Sensing

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2006
    Wei Zhang
    As newly developed techniques, distributed optical fiber sensing (DOFS) have gradually played a prominent role in structural health monitoring for the last decade. This article focuses on the employment of two types of DOFS, namely fiber Bragg grating (FBG) and Brillouin optical time domain reflectometry (BOTDR), into an integrated HMS for rehabilitated RC girder bridges by means of a series of static and dynamic loading tests to a simply supported RC T-beam strengthened by externally post-tensioned aramid fiber reinforced polymer (AFRP) tendons. Before the loading tests, a calibration test for FBG and another one for BOTDR were implemented to, respectively, obtain good linearity for both of them. Monitoring data were collected in real time during the process of external strengthening, static loading, and dynamic loading, respectively, all of which well identified the relevant structural state. The beam was finally vibrated for 2 million cycles and then loaded monotonously to failure. Based on the bending strength of externally prestressed members, ultimate values for the test specimen were numerically computed via a newly developed simplified model, which satisfactorily predicted the ultimate structural state of the beam. And then the alert values were adopted to compare with the monitoring results for safety alarm. The investigation results show a great deal of applicability for the integrated SHM by using both DOFS in rehabilitated concrete bridges strengthened by external prestressing. [source]


    Structural Health Monitoring via Measured Ritz Vectors Utilizing Artificial Neural Networks

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2006
    Heung-Fai Lam
    Unlike most other pattern recognition methods, an artificial neural network (ANN) technique is employed as a tool for systematically identifying the damage pattern corresponding to an observed feature. An important aspect of using an ANN is its design but this is usually skipped in the literature on ANN-based SHM. The design of an ANN has significant effects on both the training and performance of the ANN. As the multi-layer perceptron ANN model is adopted in this work, ANN design refers to the selection of the number of hidden layers and the number of neurons in each hidden layer. A design method based on a Bayesian probabilistic approach for model selection is proposed. The combination of the pattern recognition method and the Bayesian ANN design method forms a practical SHM methodology. A truss model is employed to demonstrate the proposed methodology. [source]


    Structural Model Updating and Health Monitoring with Incomplete Modal Data Using Gibbs Sampler

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2006
    Jianye Ching
    It is based on the Gibbs sampler, a stochastic simulation method that decomposes the uncertain model parameters into three groups, so that the direct sampling from any one group is possible when conditional on the other groups and the incomplete modal data. This means that even if the number of uncertain parameters is large, the effective dimension for the Gibbs sampler is always three and so high-dimensional parameter spaces that are fatal to most sampling techniques are handled by the method, making it more practical for health monitoring of real structures. The approach also inherits the advantages of Bayesian techniques: it not only updates the optimal estimate of the structural parameters but also updates the associated uncertainties. The approach is illustrated by applying it to two examples of structural health monitoring problems, in which the goal is to detect and quantify any damage using incomplete modal data obtained from small-amplitude vibrations measured before and after a severe loading event, such as an earthquake or explosion. [source]


    Health monitoring of plants by their emitted volatiles: trichome damage and cell membrane damage are detectable at greenhouse scale

    ANNALS OF APPLIED BIOLOGY, Issue 3 2009
    R.M.C. Jansen
    Abstract Pathogen attack and herbivore infestation have a major impact on plant health. In a model study, these two plant health issues were simulated to study whether plant health can be monitored at greenhouse scale through the analysis of volatile organic compounds (VOCs) in greenhouse atmosphere. To simulate pathogen attack and herbivore infestation, we repeatedly stroked the stems of tomato plants (Lycopersicon esculentum) and repeatedly removed their side shoots. In addition, we studied the effect of fruit picking on the concentration of plant-emitted VOCs in greenhouse atmosphere. Analysis of air samples obtained before these treatments revealed up to 17 VOCs that are known to be released from tomato plants, of which the most dominant one was the monoterpene ,-phellandrene. When plants were 7 weeks old, the concentration of this VOC was approximately 0.06 ppbv before treatment. When plants were 12 weeks old, this concentration was raised to approximately 0.14 ppbv. Stroking of the stems, removing the side shoots and fruit picking resulted in an increase in the concentrations of all mono- and most sesquiterpenes up to 60-fold, which was expected because these VOCs are well-known constituents of trichomes. The treatments did not result in substantially increased concentrations of the stress-related compounds ,-copaene, methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene. In contrast to stroking and fruit picking, shoot removal resulted in the emission of the lipoxygenase-derived product (Z)-3-hexenol in greenhouse atmosphere expressing cell membrane degradation. The findings presented in this paper focus on the feasibility of monitoring plant health through the analysis of VOCs in greenhouse air, but findings might also be relevant for atmospheric chemistry. [source]


    CONCEPTUAL CLUSTERING AND CASE GENERALIZATION OF TWO-DIMENSIONAL FORMS

    COMPUTATIONAL INTELLIGENCE, Issue 3-4 2006
    Silke Jänichen
    Case-based object recognition requires a general case of the object that should be detected. Real-world applications such as the recognition of biological objects in images cannot be solved by one general case. A case base is necessary to handle the great natural variations in the appearance of these objects. In this paper, we will present how to learn a hierarchical case base of general cases. We present our conceptual clustering algorithm to learn groups of similar cases from a set of acquired structural cases of fungal spores. Due to its concept description, it explicitly supplies for each cluster a generalized case and a measure for the degree of its generalization. The resulting hierarchical case base is used for applications in the field of case-based object recognition. We present results based on our application for health monitoring of biologically hazardous material. [source]


    Mobile Agent Computing Paradigm for Building a Flexible Structural Health Monitoring Sensor Network

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2010
    Bo Chen
    While sensor network approach is a feasible solution for structural health monitoring, the design of wireless sensor networks presents a number of challenges, such as adaptability and the limited communication bandwidth. To address these challenges, we explore the mobile agent approach to enhance the flexibility and reduce raw data transmission in wireless structural health monitoring sensor networks. An integrated wireless sensor network consisting of a mobile agent-based network middleware and distributed high computational power sensor nodes is developed. These embedded computer-based high computational power sensor nodes include Linux operating system, integrate with open source numerical libraries, and connect to multimodality sensors to support both active and passive sensing. The mobile agent middleware is built on a mobile agent system called Mobile-C. The mobile agent middleware allows a sensor network moving computational programs to the data source. With mobile agent middleware, a sensor network is able to adopt newly developed diagnosis algorithms and make adjustment in response to operational or task changes. The presented mobile agent approach has been validated for structural damage diagnosis using a scaled steel bridge. [source]


    A New Approach for Health Monitoring of Structures: Terrestrial Laser Scanning

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2007
    H. S. Park
    Three-dimensional (3D) coordinates of a target structure acquired using TLS can have maximum errors of about 10 mm, which is insufficient for the purpose of health monitoring of structures. A displacement measurement model is presented to improve the accuracy of the measurement. The model is tested experimentally on a simply supported steel beam. Measurements were made using three different techniques: (1) linear variable displacement transducers (LVDTs), (2) electric strain gages, and (3) a long gage fiber optic sensor. The maximum deflections estimated by the TLS model are less than 1 mm and within 1.6% of those measured directly by LVDT. Although GPS methods allow measurement of displacements only at the GPS receiver antenna location, the proposed TLS method allows measurement of the entire building's or bridge's deformed shape, and thus a realistic solution for monitoring structures at both structure and member level. Furthermore, it can be used to create a 3D finite element model of a structural member or the entire structure at any instance of time automatically. Through periodic measurements of deformations of a structure or a structural member and performing inverse structural analyses with the measured 3D displacements, the health of the structure can be monitored continuously. [source]


    Health Monitoring of Rehabilitated Concrete Bridges Using Distributed Optical Fiber Sensing

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2006
    Wei Zhang
    As newly developed techniques, distributed optical fiber sensing (DOFS) have gradually played a prominent role in structural health monitoring for the last decade. This article focuses on the employment of two types of DOFS, namely fiber Bragg grating (FBG) and Brillouin optical time domain reflectometry (BOTDR), into an integrated HMS for rehabilitated RC girder bridges by means of a series of static and dynamic loading tests to a simply supported RC T-beam strengthened by externally post-tensioned aramid fiber reinforced polymer (AFRP) tendons. Before the loading tests, a calibration test for FBG and another one for BOTDR were implemented to, respectively, obtain good linearity for both of them. Monitoring data were collected in real time during the process of external strengthening, static loading, and dynamic loading, respectively, all of which well identified the relevant structural state. The beam was finally vibrated for 2 million cycles and then loaded monotonously to failure. Based on the bending strength of externally prestressed members, ultimate values for the test specimen were numerically computed via a newly developed simplified model, which satisfactorily predicted the ultimate structural state of the beam. And then the alert values were adopted to compare with the monitoring results for safety alarm. The investigation results show a great deal of applicability for the integrated SHM by using both DOFS in rehabilitated concrete bridges strengthened by external prestressing. [source]


    Structural Model Updating and Health Monitoring with Incomplete Modal Data Using Gibbs Sampler

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2006
    Jianye Ching
    It is based on the Gibbs sampler, a stochastic simulation method that decomposes the uncertain model parameters into three groups, so that the direct sampling from any one group is possible when conditional on the other groups and the incomplete modal data. This means that even if the number of uncertain parameters is large, the effective dimension for the Gibbs sampler is always three and so high-dimensional parameter spaces that are fatal to most sampling techniques are handled by the method, making it more practical for health monitoring of real structures. The approach also inherits the advantages of Bayesian techniques: it not only updates the optimal estimate of the structural parameters but also updates the associated uncertainties. The approach is illustrated by applying it to two examples of structural health monitoring problems, in which the goal is to detect and quantify any damage using incomplete modal data obtained from small-amplitude vibrations measured before and after a severe loading event, such as an earthquake or explosion. [source]


    Nonparametric Identification of a Building Structure from Experimental Data Using Wavelet Neural Network

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2003
    Shih-Lin Hung
    By combining wavelet decomposition and artificial neural networks (ANN), wavelet neural networks (WNN) are used for solving chaotic signal processing. The basic operations and training method of wavelet neural networks are briefly introduced, since these networks can approximate universal functions. The feasibility of structural behavior modeling and the possibility of structural health monitoring using wavelet neural networks are investigated. The practical application of a wavelet neural network to the structural dynamic modeling of a building frame in shaking tests is considered in an example. Structural acceleration responses under various levels of the strength of the Kobe earthquake were used to train and then test the WNNs. The results reveal that the WNNs not only identify the structural dynamic model, but also can be applied to monitor the health condition of a building structure under strong external excitation. [source]


    Decentralized Parametric Damage Detection Based on Neural Networks

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2002
    Zhishen Wu
    In this paper, based on the concept of decentralized information structures and artificial neural networks, a decentralized parametric identification method for damage detection of structures with multi-degrees-of-freedom (MDOF) is conducted. First, a decentralized approach is presented for damage detection of substructures of an MDOF structure system by using neural networks. The displacement and velocity measurements from a substructure of a healthy structure system and the restoring force corresponding to this substructure are used to train the decentralized detection neural networks for the purpose of identifying the corresponding substructure. By using the trained decentralized detection neural networks, the difference of the interstory restoring force between the damaged substructures and the undamaged substructures can be calculated. An evaluation index, that is, relative root mean square (RRMS) error, is presented to evaluate the condition of each substructure for the purpose of health monitoring. Although neural networks have been widely used for nonparametric identification, in this paper, the decentralized parametric evaluation neural networks for substructures are trained for parametric identification. Based on the trained decentralized parametric evaluation neural networks and the RRMS error of substructures, the structural parameter of stiffness of each subsystem can be forecast with high accuracy. The effectiveness of the decentralized parametric identification is evaluated through numerical simulations. It is shown that the decentralized parametric evaluation method has the potential of being a practical tool for a damage detection methodology applied to structure-unknown smart civil structures. [source]


    Rule,based reasoning and neural network perception for safe off,road robot mobility

    EXPERT SYSTEMS, Issue 4 2002
    Edward Tunstel
    Operational safety and health monitoring are critical matters for autonomous field mobile robots such as planetary rovers operating on challenging terrain. This paper describes relevant rover safety and health issues and presents an approach to maintaining vehicle safety in a mobility and navigation context. The proposed rover safety module is composed of two distinct components: safe attitude (pitch and roll) management and safe traction management. Fuzzy logic approaches to reasoning about safe attitude and traction management are presented, wherein inertial sensing of safety status and vision,based neural network perception of terrain quality are used to infer safe speeds of traversal. Results of initial field tests and laboratory experiments are also described. The approach provides an intrinsic safety cognizance and a capacity for reactive mitigation of robot mobility and navigation risks. [source]


    Piezoelectric wafer active sensors for in situ ultrasonic-guided wave SHM

    FATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8 2008
    L. YU
    ABSTRACT In situ structural health monitoring aims to perform on-demand interrogation of the structure to determine the presence of service-induced damage and defects using non-destructive evaluation ultrasonic wave methods. Recently emerged piezoelectric wafer active sensors (PWAS) have the potential to significantly improve damage detection and health monitoring. PWAS are low-profile transducers that can be permanently attached onto the structure or inserted in between composite laminates, and can perform structural damage detection in thin-wall structures using guided wave methods (Lamb, Rayleigh, SH, etc.). This paper describes the analytical and experimental work of using PWAS-guided waves for in situ structural damage detection on thin-wall structures. We begin with reviewing the guided wave theory in plate structures and PWAS principles. The mechanisms of Lamb wave excitation and detection using PWAS is presented. Subsequently, we address in turn the use of PWAS to generate Lamb waves for damage (cracks and corrosion) detection in metallic structures. Pulse-echo, pitch-catch, phased array and time reversal methods are illustrated demonstrating that PWAS Lamb-waves techniques are suitable for damage detection and structural health monitoring. The last part of the paper treats analytically and experimentally PWAS excitation and tuning in composite materials. The research results presented in this paper show that in situ SHM methodologies using PWAS transducers hold the promise for more efficient, effective and timely damage detection in thin-wall structures. [source]


    Fabrication and Electromechanical Characterization of a Piezoelectric Structural Fiber for Multifunctional Composites

    ADVANCED FUNCTIONAL MATERIALS, Issue 4 2009
    Yirong Lin
    Abstract The use of piezoceramic materials for structural sensing and actuation is a fairly well developed practice that has found use in a wide variety of applications. However, just as advanced composites offer numerous benefits over traditional engineering materials for structural design, actuators that utilize the active properties of piezoelectric fibers can improve upon many of the limitations encountered when using monolithic piezoceramic devices. Several new piezoelectric fiber composites have been developed; however, almost all studies have implemented these devices such that they are surface-bonded patches used for sensing or actuation. This paper will introduce a novel active piezoelectric structural fiber that can be laid up in a composite material to perform sensing and actuation, in addition to providing load bearing functionality. The sensing and actuation aspects of this multifunctional material will allow composites to be designed with numerous embedded functions, including structural health monitoring, power generation, vibration sensing and control, damping, and shape control through anisotropic actuation. This effort has developed a set of manufacturing techniques to fabricate the multifunctional fiber using a SiC fiber core and a BaTiO3 piezoelectric shell. The electromechanical coupling of the fiber is characterized using an atomic force microscope for various aspect ratios and is compared to predictions made using finite element modeling in ABAQUS. The results show good agreement between the finite element analysis model and indicate that the fibers could have coupling values as high as 68% of the active constituent used. [source]


    Quantitative structural damage detection using high-frequency piezoelectric signatures via the reverberation matrix method

    INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2007
    W. Yan
    Abstract High-frequency structural analysis so far has been a major issue in dynamic analysis, for which many conventional methods such as finite element method and transfer matrix method are unable to perform well. Since the electromechanical impedance technique for structural health monitoring (SHM) operates at very high frequencies, the reverberation matrix method (RMM), which was just developed a few years ago, is employed to study dynamics of the monitored structures, which are bonded with piezoelectric lead zirconate titanate (PZT) patches. A piecewisely homogeneous Euler,Bernoulli beam model is introduced to approximate the non-homogeneous beam and only one-dimensional axial vibration of PZT wafers is considered. The imperfect interfacial bonding between PZT patches and the host beam is investigated based on a shear lag model. Using a hybrid technique combining electromechanical impedance method and RMM, an analytical expression of impedance (or admittance) related to the response of the coupled model of PZT patch-bonding layer-host beam system is derived for SHM. The proposed method is examined by comparing with other theoretical methods as well as by means of a test on an intelligent system using a steel beam with two symmetrically installed PZT wafers. It could be further applied to predicting the dynamics of monitored Timoshenko beams, continuous beams, and framed structures as well. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Innovative approach to health promotion for the over 45s: using a health check log

    INTERNATIONAL JOURNAL OF OLDER PEOPLE NURSING, Issue 4 2008
    BAppSc (AN), June N. Sheriff CM, MHPEd
    Objectives., To determine effectiveness of the health check log (HCL) in promoting health-related quality of life and health awareness, health monitoring skills and timely consultation with health professionals for a cohort of community-dwelling people over 45 years, compared with a similar cohort not recording the HCL. Design., An exploratory longitudinal study using a quasi-experimental methodology and data triangulation. Outcome measures included the SF-36 health survey; a semi-structured participant feedback survey and participant focus group discussions. Sample., A convenience sample (n = 309) of community dwellers over the age of 45 living in the South Eastern Sydney/Illawarra Area Health Service, Sydney, Australia. Results., The majority of participants recording the HCL reported health benefits. The SF-36 health survey found younger age is a predictor for positive change in ,social functioning' (, = ,0.14, t = 2.25, P < 0.05), while non-pension income was a predictor of positive ,physical functioning' (, = 0.12, t = 2.02, P < 0.05) and ,general health' (, = 0.13, t = 2.11, P < 0.05). Alternatively, full-time employment (, = ,0.12, t = 2.02, P < 0.05) and not living alone (, = 0.18, t = 3.09, P < 0.01) predicted negative change in ,role , physical'. Participant reactions to recording the HCL via feedback survey and focus group discussions were mostly positive. Conclusions., The majority who maintained the HCL benefited by achieving improved health and knowledge of health monitoring, which was, however, moderated by age, income source, employment status and living arrangements. [source]


    Longitudinal analysis of inpatient care utilization among people with intellectual disabilities: 1999,2002

    JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 2 2007
    C.-H. Loh
    Abstract Background There has been no longitudinal study in Taiwan to identify the nature and the scale of medical care utilization of people with intellectual disabilities (IDs) up to the present. The aim of this study is to describe inpatient utilization among people under ID care in institutions in order to identify the pattern of medical care needs and the factors affecting utilization in Taiwan. Method The subject cohort was 168 individuals with ID who were cared for by a large public disability institution from 1999 to 2002 in Taipei, Taiwan. Results On the examination of the inpatient care that these persons underwent, it was found that these individuals had a heightened need (inpatient rate: 10.1,14.9%) for inpatient care compared with the general population with disabilities (9.37%) in Taiwan. The main reasons for hospitalization were pneumonia, gastrointestinal disorders, cellulites, orthopaedic problems, epilepsy and bronchitis. Using the full model of Generalized Estimating Equations for inpatient care utilization, the factors including low income family, living in an institution, being a subject with cerebral palsy and being a high outpatient user all influenced the use of inpatient care. Conclusions This study highlights that health authorities need to promote health planning more in order to ensure an excellent quality of health monitoring and health promotion among people with ID cared for by institutions. [source]


    A prevalence survey for zoonotic enteric bacteria in a research monkey colony with specific emphasis on the occurrence of enteric Yersinia

    JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2001
    Stephen J. Vore
    Transmissible pathogenic and opportunistic zoonotic enteric bacteria comprise a recognized occupational health threat to exposed humans from non-human primates (NHPs). In an effort to evaluate the occurrence of selected enteric organisms with zoonotic and biohazard potential in a research colony setting, we performed a prevalence study examining 61 juvenile and young adult rhesus macaques participating in a transplant immunology project. Primary emphasis was directed specifically to detection of pathogenic enteric Yersinia, less well-documented and reported NHP pathogens possessing recognized significant human disease potential. NHPs were surveyed by rectal culture during routine health monitoring on three separate occasions, and samples incubated using appropriate media and specific selective culture methods. Enteric organisms potentially transmissible to humans were subcultured and identified to genus and species. Significant human pathogens of the Salmonella/Shigella, Campylobacter, and enteric Yersinia groups were not isolated throughout the survey, suggesting prevalence of these organisms may generally be quite low. [source]


    Scopoli's work in the field of mercurialism in light of today's knowledge: Past and present perspectives

    AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 5 2010
    Alfred Bogomir Kobal MD
    Abstract The Idrija Mercury Mine (1490,1994) appointed its first physician, Joannes Antonius Scopoli, in 1754. Most of his descriptions of mercurialism are still relevant today. This study highlights Scopoli's observations on the interaction between elemental mercury (Hg°) and alcohol, on the appearance of lung impairment, insomnia, and depressive mood in mercurialism. This presentation is based on Scopoli's experiences presented in his book, De Hydrargyro Idriensi Tentamina (1761), current knowledge, and our own experience acquired through health monitoring of occupational Hg° exposure. Some studies have confirmed Scopoli's observation that alcohol enhances mercurialism and his hypothesis that exposure to high Hg° concentrations causes serious lung impairment. Neurobiological studies have highlighted the influence of Hg° on sleep disorder and depressive mood observed by Scopoli. Although today's knowledge provides new perspectives of Scopoli's work on mercurialism, his work is still very important and can be considered a part of occupational medicine heritage. Am. J. Ind. Med. 53:535-547, 2010. © 2010 Wiley-Liss, Inc. [source]


    A longitudinal study of urinary dipstick parameters in wild chimpanzees (Pan troglodytes verus) in Côte d'Ivoire

    AMERICAN JOURNAL OF PRIMATOLOGY, Issue 8 2010
    Siv Aina J. Leendertz
    Abstract We performed 796 dip-stick tests on urine from 100 wild West African chimpanzees (Pan troglodytes verus) from 4 habituated groups in the tropical rain forest of Taï National Park, Cote d'Ivoire, to establish reference values for health monitoring. Specific gravity was also measured on 359 urine samples from 62 chimpanzees. The effect of age, sex, group, month, estrus, pregnancy, meat consumption, and acute respiratory disease on pH, leucocytes, protein, blood, hemoglobin, and glucose was examined using ordinal logistic regression. The presence of nitrite, ketones, bilirubin, and urobilinogen in urine was also recorded. Outbreak of acute respiratory disease did not influence any of the urinary parameters. Thirty-seven percent of the samples had a pH <7 and the whole range of pH was found through the year, in all age groups, and in both sexes. Meat consumption lowered the urinary pH. Our results show that all pH levels must be considered normal for the West African chimpanzee subspecies P. troglodytes verus living in the rainforest. We also found a cluster of glucose-positive samples at a specific point in time which was not attributed to diabetes mellitus. These findings highlight that there are differences in normal physiological parameters among wild chimpanzees living in different habitats. Am. J. Primatol. 72:689,698, 2010. © 2010 Wiley-Liss, Inc. [source]


    A geomorphological framework for river characterization and habitat assessment

    AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2001
    J.R. Thomson
    Abstract 1.,Methods to assess the physical habitat available to aquatic organisms provide important tools for many aspects of river management, including river health monitoring, determination of river restoration/rehabilitation strategies, setting and evaluating environmental flows and as surrogates for biodiversity assessment. 2.,Procedures used to assess physical habitat need to be ecologically and geomorphologically meaningful, as well as practicable. A conceptual methodological procedure is presented that evaluates and links instream habitat and geomorphology. 3.,The heterogeneity of habitat potential is determined within geomorphic units (such as pools, runs, riffles) by assessing flow hydraulics and substrate character. These two variables are integrated as hydraulic units , patches of uniform flow and substrate. 4.,This methodology forms a logical extension of the River Styles framework that characterizes river form and behaviour at four inter-related scales: catchments, landscape units, River Styles (reaches) and geomorphic units. As geomorphic units constitute the basis to assess aquatic habitat availability, and they form the building blocks of river and floodplain systems, intact reaches of a particular River Style should have similar assemblages of instream and floodplain habitat. 5.,An application of the hydraulic unit procedure is demonstrated in gorge, partly-confined and alluvial River Styles from the Manning catchment in northern New South Wales, Australia. Copyright © 2001 John Wiley & Sons, Ltd. [source]