Nature and Origin of Micropollutants

1982 ◽  
Vol 14 (12) ◽  
pp. 5-14 ◽  
Author(s):  
D Mackay
Keyword(s):  
Adverse Effects ◽  
Toxicity Data ◽  
Low Level ◽  
Environmental Models ◽  
Toxic Event ◽  
And Control

The origins of “micropollutants” are discussed and classified. It is suggested that assessing the risk and ensuring an acceptably low level of adverse effects from these substances requires information or control of three factors (exposure, toxicity and characteristics of the victim or organism) which combine to generate the toxic event. Methods of estimating exposure are discussed, especially environmental models. Ultimately, it should be possible to couple these models to toxicity data in a rational, rigorous manner to elucidate the extent of risk and control it to acceptable levels.

Effect of Ultrasound on the Fetus

1987 ◽  
Vol 8 (8) ◽  
pp. 228-253
Keyword(s):  
Adverse Effects ◽  
Human Fetus ◽  
Matched Control ◽  
Subsequent Development ◽  
Childhood Malignancy ◽  
Ultrasonic Examination ◽  
The United Kingdom ◽  
Dna Alterations ◽  
And Control

The question of adverse effects of ultrasonic examination upon the human fetus continues to be explored. The impetus for these investigations comes from animal or in vitro cellular studies showing a reduction of weight and size and DNA alterations in mice litters exposed to ultrasound. Human studies to date have failed to reveal any comparable results. These two articles explore whether there is a positive correlation between fetal ultrasonic examination and/or monitoring and subsequent development of childhood malignancy. The first study reports comparison of histories from 1,731 children who died of cancer in the United Kingdom between 1972 and 1981 with age-matched control children for exposure. Six percent of both case and control children had had ultrasonic exposure.

Ecotoxicity Effects of Nanomaterials on Aquatic Organisms

2016 ◽  
pp. 330-351 ◽  
Author(s):  
César A Barbero ◽  
Edith Inés Yslas
Keyword(s):  
Adverse Effects ◽  
Surface Charge ◽  
Direct Effect ◽  
Mechanism Of Action ◽  
Aquatic Environment ◽  
Physicochemical Characteristic ◽  
Aquatic Organisms ◽  
Development Stage ◽  
Engineered Nanomaterials ◽  
Toxicity Data

The increasing production and use of engineered nanomaterials raise concerns about inadvertent exposure and the potential for adverse effects on the aquatic environment. The aim of this chapter is focused on studies of nanotoxicity in different models of aquatic organisms and their impact. Moreover, the chapter provides an overview of nanoparticles, their applications, and the potential nanoparticle-induced toxicity in aquatic organisms. The topics discussed in this chapter are the physicochemical characteristic of nanomaterials (size, aggregation, morphology, surface charge, reactivity, dissolution, etc.) and their influence on toxicity. Further, the text discusses the direct effect of nanomaterials on development stage (embryonic and adult) in aquatic organisms, the mechanism of action as well as the toxicity data of nanomaterials in different species.f action as well as the toxicity data of nanomaterials in different species.

scholarly journals A Vigilance Explanation of Musical Chills? Effects of Loudness and Brightness Manipulations

2020 ◽  
Vol 3 ◽  
pp. 205920432091565
Author(s):  
Scott Bannister
Keyword(s):  
Emotional Experience ◽  
Spectral Brightness ◽  
Musical Structure ◽  
Low Level ◽  
Complex Interactions ◽  
Musical Structures ◽  
Study Participants ◽  
And Control ◽  
Auditory Looming ◽  
Control Piece

Recent research has suggested that low-level psychoacoustic parameters such as loudness and spectral brightness are correlated with musical chills, a subjective emotional experience accompanied by goosebumps, shivers, and tingling sensations. These relationships may be explained by a vigilance theory of chills, through the process of auditory looming; however, these correlations or theories have never been causally tested. In the current study, participants ( N = 40) listened to five variations (original, low loudness, high loudness, low brightness, high brightness) of an experimental and control piece of chills music, characterized by a crescendo and guitar solo respectively; this qualitative distinction was made based on whether the underlying musical structure of the pieces was or was not capable of engaging auditory looming processes. It was predicted that increases in loudness would result in increased chills frequency across participants, indicated by button presses; brightness was included as an exploratory parameter. Results show that for the experimental piece, increases in loudness resulted in significantly more frequent chills experiences, and increases in brightness significantly reduced the frequency of chills, whereas no effects were found for the control piece. Findings are discussed in terms of vigilance and social bonding theories of chills, and the complex interactions between low-level psychoacoustic properties and higher-level musical structures.

scholarly journals Prevalence, awareness and control of hypertension among Tunisian adults, 2016

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
I Cherif ◽  
N Ben Mansour ◽  
S Rejaibi ◽  
N Zoghlami ◽  
O Saidi ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Associated Factors ◽  
Healthy Lifestyle ◽  
Health Examination ◽  
Control Input ◽  
Hypertension Control ◽  
Low Level ◽  
Lifestyle Measures ◽  
Hypertension Screening ◽  
And Control

Abstract Background Hypertension is becoming increasingly frequent mainly in low and middle income countries. We aimed to assess the prevalence, awareness and control of hypertension among Tunisian adults and identify associated factors with hypertension control. Methods Data were obtained from the 2016 Tunisian Health Examination Survey, a household survey stratified at three degrees. Adults (age≥18 years old) were interviewed using an individual questionnaire, then three blood pressure measurement were performed. Participants were considered hypertensive if they were previously diagnosed or had a systolic blood pressure (SBP) ≥140mmhg and/or a diastolic blood pressure (DBP) ≥ 90mmhg during the survey. Were considered under control, treated persons with SBP<140 mmhg and a DBP<90 mmhg. A weighted binary logistic regression was used to assess associated factors with hypertension control. Input model variables were: sociodemographic variables, comorbidities and lifestyle factors. Results In this study, 8908 adults were enrolled with a mean age of 42.8±0.2 years old and a sex ratio (M/F) equal to 0.96. Among respondents, 29.3% (95% CI: 28.2-30.5) had hypertension, 60.7% (95% CI: 58.7-62.6) of them were unaware of their disease and only (29.5%, 95% CI: 28.2-30.5) of treated patients had a controlled hypertension. In multivariate analysis, eating more than five fruits and vegetables per day was independently associated with a better hypertension control (AOR=1.7, 95% CI: 1.1-2.5). In addition, participants living in northern Tunisia were more likely to have a controlled hypertension than those living in the south (AOR=1.9, 95% CI: 1.2-2.9). Conclusions Almost third of Tunisian adults were hypertensive. Low level of awareness and control of hypertension were found in this study. This highlights the urge to reinforce hypertension screening interventions and to strengthen educational programs on this disease with a focus on blood pressure monitoring and healthy lifestyle measures. Key messages Tunisian adults had a low level of awareness and control of hypertension. Reinforcing hypertension screening interventions and increasing awareness about healthy lifestyle measures are recommended.

Powered Ankle-Foot Prostheses: A Survey on Sensing Systems and Control Strategies

2019 ◽  
Author(s):  
Erik Chumacero-Polanco ◽  
James Yang
Keyword(s):  
Control Strategies ◽  
Level Control ◽  
Low Level ◽  
Kinetic Information ◽  
Sensing Systems ◽  
Systems And Control ◽  
Finite State ◽  
High Level ◽  
And Control

Abstract People who have suffered a transtibial amputation show diminished ambulation and impaired quality of life. Powered ankle foot prostheses (AFP) are used to recover some mobility of transtibial amputees (TTAs). Powered AFP is an emerging technology that has great potential to improve the quality of life of TTAs with important avenues for research and development in different fields. This paper presents a survey on sensing systems and control strategies applied to powered AFPs. Sensing kinematic and kinetic information in powered AFPs is critical for control. Ankle angle position is commonly obtained via potentiometers and encoders directly installed on the joint, velocities can be estimated using numerical differentiators, and accelerations are normally obtained via inertial measurement units (IMUs). On the other hand, kinetic information is usually obtained via strain gauges and torque sensors. On the other hand, control strategies are classified as high- and low-level control. The high-level control sets the torque or position references based on pattern generators, user’s intent of motion recognition, or finite-state machine. The low-level control usually consists of linear controllers that drive the ankle’s joint position, velocity, or torque to follow an imposed reference signal. The most widely used control strategy is the one based on finite-state machines for the high-level control combined with a proportional-derivative torque control for low-level. Most designs have been experimentally assessed with acceptable results in terms of walking speed. However, some drawbacks related to powered AFP’s weight and autonomy remain to be overcome. Future research should be focused on reducing powered AFP size and weight, increasing energy efficiency, and improving both the high- and the low-level controllers in terms of efficiency and performance.

A Comparative Study on Short-Term Effects of Compression Orthosis and Exercises in the Treatment of Pectus Carinatum: A Randomized Controlled Pilot Feasibility Trial

2020 ◽  
Author(s):  
Esra Giray ◽  
Nezih Onur Ermerak ◽  
Yeliz Bahar-Ozdemir ◽  
Melihat Kalkandelen ◽  
Mustafa Yuksel ◽  
...  
Keyword(s):  
Adverse Effects ◽  
Chest Wall ◽  
Feasibility Trial ◽  
Control Group ◽  
Pectus Carinatum ◽  
Short Term ◽  
Similar Frequency ◽  
Custom Made ◽  
Before And After ◽  
And Control

Abstract Introduction Pectus carinatum (PC) is a congenital chest wall deformity which is characterized by the protrusion of the sternum and costal cartilages. Although orthotic and exercise therapies are commonly offered by physicians for PC treatment, there is a lack of evidence on the benefits of exercises and how long the orthosis should be worn. The aim of this study is to investigate the effects and feasibility of custom-made compression orthosis and exercises in the treatment of PC. Materials and Methods Patients with PC aged 7 to 17 years old were randomized into three groups: compression orthosis 23 hours, compression orthosis 8 hours, and control group. All groups received exercises for 1 hour a day for 3 weeks. Additionally, compression orthosis 23 hours group wore the orthosis for 23 hours a day, while compression orthosis 8 hours group wore the orthosis for 8 hours a day. PC protrusion, pressure of correction, thorax lateral and anteroposterior parameters, external chest wall measurements, and Nuss Questionnaire were evaluated before and after the treatment. Also, adverse effects, retention, and compliance were assessed. Feasibility was evaluated by calculating the percentages of recruitment, retention, and safety. Results The compression orthosis 23 hours group showed greater improvements than the other groups. After treatment, all groups showed significant changes in protrusion, pressure of correction, and external chest wall measurements. Adverse events occurred with similar frequency across groups. Retention percentages did not differ among groups. Conclusion Compression orthosis use for 23 hours can be recommended rather than its use for 8 hours because 23 hours of orthosis use has better correction and similar adverse effects.

scholarly journals Chronic and Acute Toxicities of Aflatoxins: Mechanisms of Action

2020 ◽  
Vol 17 (2) ◽  
pp. 423 ◽  
Author(s):  
Noreddine Benkerroum
Keyword(s):  
Oxidative Stress ◽  
Risk Factors ◽  
Adverse Effects ◽  
Mechanisms Of Action ◽  
Additive Effects ◽  
Hepatitis Viruses ◽  
Mechanisms Of Toxicity ◽  
Adverse Health Effects ◽  
Relative Contribution ◽  
And Control

There are presently more than 18 known aflatoxins most of which have been insufficiently studied for their incidence, health-risk, and mechanisms of toxicity to allow effective intervention and control means that would significantly and sustainably reduce their incidence and adverse effects on health and economy. Among these, aflatoxin B1 (AFB1) has been by far the most studied; yet, many aspects of the range and mechanisms of the diseases it causes remain to be elucidated. Its mutagenicity, tumorigenicity, and carcinogenicity—which are the best known—still suffer from limitations regarding the relative contribution of the oxidative stress and the reactive epoxide derivative (Aflatoxin-exo 8,9-epoxide) in the induction of the diseases, as well as its metabolic and synthesis pathways. Additionally, despite the well-established additive effects for carcinogenicity between AFB1 and other risk factors, e.g., hepatitis viruses B and C, and the hepatotoxic algal microcystins, the mechanisms of this synergy remain unclear. This study reviews the most recent advances in the field of the mechanisms of toxicity of aflatoxins and the adverse health effects that they cause in humans and animals.

Low level of systemic autoimmunity in Western Australian multiple sclerosis patients

2010 ◽  
Vol 16 (3) ◽  
pp. 351-354 ◽  
Author(s):  
Wei Qiu ◽  
Christine Bundell ◽  
Jing-Shan Wu ◽  
Alison Castley ◽  
Ian James ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Antinuclear Antibody ◽  
Aquaporin 4 ◽  
Low Level ◽  
Control Subjects ◽  
Systemic Autoimmunity ◽  
Multiple Sclerosis Patients ◽  
And Control ◽  
Western Australian

Previous autoantibody (AAb) studies in multiple sclerosis MS have produced conflicting results. The objective of this study was to determine AAb frequency and association with the HLA-DRB1 genotype. Antinuclear antibody, antithyroid peroxidase and anti-aquaporin-4 assays and HLA-DRB1 genotyping were performed in 198 MS patients and 188 controls. There were no significant differences in AAb frequency or titres between MS and control subjects. AQP4-IgG was not found in any MS patients. There was no correlation between AAbs and HLA-DRB1 alleles. In conclusion, this study failed to confirm previous reports of increased AAbs in MS or to show an association between HLA-DRB1 genotype and the presence of AAbs.

Behaviour Treatment of Daytime Incontinence in Elderly Male and Female Patients

1986 ◽  
Vol 14 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Diana Chanfreau-Rona ◽  
Belinda Wylie ◽  
Stuart Bellwood
Keyword(s):  
Training Programme ◽  
Training Period ◽  
Control Group ◽  
Control Groups ◽  
Elderly Male ◽  
Severe Problem ◽  
Male And Female ◽  
Low Level ◽  
And Control ◽  
Experimental Group

This paper describes an attempt at retraining continence in elderly psychogeriatric patients using behavioural methods. Thirty patients across four wards were selected and divided equally into experimental and control groups. The experimental group underwent a training programme lasting a total of seven weeks whilst the control group continued with the usual nursing procedure.The results showed no significant differences in frequency of incontinence between the different groups at the end of the programme. However, there were indications that a continence training programme is more likely to be beneficial to those patients who have a low level of incontinence rather than those for whom incontinence is a more severe problem. For these patients, those in the experimental group showed increased levels of incontinence after the training period compared to the control group.

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