Search results for " DISTURBANCE"
showing 10 items of 133 documents
Contrasting Effects of Chronic Anthropogenic Disturbance on Activity and Species Richness of Insectivorous Bats in Neotropical Dry Forest
2022
For prioritizing conservation actions, it is vital to understand how ecologically diverse species respond to environmental change caused by human activity. This is particularly necessary considering that chronic human disturbance is a threat to biodiversity worldwide. Depending on how species tolerate and adapt to such disturbance, ecological integrity and ecosystem services will be more or less affected. Bats are a species-rich and functionally diverse group, with important roles in ecosystems, and are therefore recognized as a good model group for assessing the impact of environmental change. Their populations have decreased in several regions, especially in the tropics, and are threatene…
Worsening of Preexisting Psychiatric Conditions During the COVID-19 Pandemic
2020
Objectives: To ascertain factors associated with worsening of psychiatric conditions during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This study anonymously examined 2,734 psychiatric patients worldwide for worsening of their preexisting psychiatric conditions during the COVID-19 pandemic. An independent clinical investigation of 318 psychiatric patients from United States was used for verification. Results: Valid responses mainly from 12 featured countries indicated self-reported worsening of psychiatric conditions in two-thirds of the patients assessed that was through their significantly higher scores on scales for general psychological disturbance, posttraumatic stress …
Coping with continual danger: assessing alertness to visual disturbances in crucian carp following long-term exposure to chemical alarm signals.
2013
Chemical alarm signals in fish are passively released into the water from ruptured epidermal cells, and induce instant fright responses in conspecifics. Fish also display alarm responses to injured heterospecific skin, as well as to scent of piscivorous predators that have ingested prey. A conspicuous alertness to visual disturbances has also been observed in fish following long-term exposure to extracts of filtered, homogenized skin, but the chemical inducers of such vigilance are actually unknown. We tested if a continual exposure to water-soluble alarm signals, from either conspecifics or heterospecifics, affects alertness of fish. Based on previous experience, it was assumed that alertn…
Sleep disordered breathing in medically stable patients with myasthenia gravis
2007
We investigate sleep and breathing in clinically stable myasthenia gravis (MG) patients and ask weather sleep disordered breathing (SDB) is causally linked with MG. Nineteen MG patients with a mean disease duration of 9.7 years underwent sleep studies in two consecutive nights. The primary outcome measure was the respiratory disturbance index (RDI) in terms of snoring and apneas/hypopneas. Further outcome measurements were total sleep time, sleep stage distribution and the number of arousals. A clinically relevant SDB in terms of obstructive sleep apnea (OSA) (defined as RDI > 10/h) was found in four patients. There were only a few central apneas (central apnea index: 0.19 +/- 0.4/h). We di…
Effects of adenotonsillectomy on neurocognitive and behavioural function in pediatric obstructive sleep apnea syndrome
2018
Effects of adenotonsillectomy on neurocognitive and behavioural function in pediatric obstructive sleep apnea syndrome. Objectives: Aim of this study is to verify the presence of neurocognitive, neurobehavioral or sleep disturbances in children affected by adenotonsillar hypertrophy (ATH) and Obstructive Sleep Apnea Syndrome (OSAS) and verify their improvement after Adeno-Tonsillectomy (AT). Methods: Eighty children suffering from adenotonsillar hypertrophy and OSAS were recruited for AT in the ENT Department of the University of Palermo. All the children underwent clinical evaluation, including rhinofibroscopy for grading the obstruction due to the adenotonsillar hypertrophy (before and 6 …
Self‐esteem mediates the associations among negative affect, body disturbances, and interpersonal problems in treatment‐seeking obese individuals
2015
Background: This study investigated the relationship among negative affect, body image disturbances (BID), and interpersonal problems, and the mediat- ing effect of self-esteem in a group of treatment-seeking obese individuals. Methods: Four hundred twenty-two obese patients (85 males and 337 females) completed standardised measures that assessed negative affect, BID, self-esteem, and interpersonal problems. Results: Structural equation modelling showed that obese individuals with greater negative affect and BID reported higher interpersonal problems and that self-esteem mediated the relationships among negative affect, BID, and interpersonal problems. Conclusions: The mediating role of sel…
Crowd-Averse Cyber-Physical Systems: The Paradigm of Robust Mean-Field Games
2016
For a networked controlled system, we illustrate the paradigm of robust mean-field games. This is a modeling framework at the interface of differential game theory, mathematical physics, and $H_{\infty}$ - optimal control that tries to capture the mutual influence between a crowd and its individuals. First, we establish a mean-field system for such games including the effects of adversarial disturbances. Second, we identify the optimal response of the individuals for a given population behavior. Third, we provide an analysis of equilibria and their stability.
Active Disturbance Rejection Control of Synchronous Reluctance Motors
2020
This paper describes how the ADRC (Active Disturbance Rejection Control) strategy can be successfully applied to SynRM (Synchronous Reluctance Motor) drives. The ADRC is an adaptive robust extension of the input-output Feedback Linearization Control (FLC). Its main feature is that the nonlinear transformation of the state is computed on-line and not by using the model. As a consequence, any unmodelled dynamics or uncertainty of the parameters can be addressed. The control strategy has been verified successfully with experimental tests confirming the high dynamic response of the drive.
Load frequency regulation using observer based non-linear sliding mode control
2019
Abstract In this paper, the generalized extended state observer (GESO) and non-linear sliding mode control (SMC) are merged together to study the frequency deviation problem in multi-area power system. In study, the GESO is used not only for state and disturbance estimation but also for disturbance rejection of the system. The said observer ensures accurate estimation of the actual states leading to convergence of estimation error to zero. The non-linear SMC is used to increase the damping ratio of the system whenever, any perturbations occurs. The proposed observer based controller is compared with an existing two-layer active disturbance rejection control (ADRC) and also validated on larg…
Histopathological progression of hidradenitis suppurativa/acne inversa
2021
It is generally acknowledged that the first morphological change of hidradenitis suppurativa/acne inversa (HS/AI) consists of infundibular plugging of the folliculosebaceous apocrine apparatus, which is followed by acute and chronic inflammation, cysts with sinus formation, and fibrosis. Alternatively, it has been hypothesized that HS/AI is primarily a neutrophilic autoinflammatory disease and that the follicular plugging typical of this disease is secondary to inflammation.To review the sequence of the changes that mark the disease development, we have performed a histopathologic study on the surgical material from a series of axillary and inguinal/perineal cases.The histologic material fr…