low-frequency sources
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Doporučuje se využít při posuzování hluku v obytných budovách prosté kvalitativní porovnání úzkopásmových spekter hluku a vibrací. Navrhuje se spektra sdružit a graficky zobrazit. Metoda se osvědčila při řešení stížností na hluk z technických zdrojů umístěných v budovách jako jsou výměníkové stanice, výtahy atp. Ukázalo se, že spektrům hluku a vibrací zjištěným v chráněných prostorech se mnohem více podobá spektrum vibrací nosné konstrukce příslušného zdroje než spektrum hluku naměřené v blízkosti tohoto zdroje. Metoda je méně náročná než jiné technické metody identifikace zdroje, jako je např. měření koherence signálů. Při jejím použití není třeba současně měřit v místě zdroje a v chráněném prostoru. Metoda napomáhá při posuzování oprávněnosti stížností na hluk a je jí možno použít při návrhu technických opatření na snižování hluku. Bylo zjištěno, že po delším pobytu je možno subjektivně identifikovat nízkofrekvenční hluky, jejichž hladina leží podle příslušných mezinárodních norem hluboko pod prahem sluchu.
For the assessment of noise in dwellings the use a simple qualitative comparison of narrow-band noise and vibration spectra is recommended. It is suggested to associate the spectra and present them graphically. The proposed method was successfully tested during the solution of several complaints on noise caused by technical sources installed in buildings such as heat exchanger station lifts etc. As it was proved the vibration and noise spectra in living areas correspond much more to the vibration spectra of the noise sources support than the consequent noise spectra measured near the source. The use of the method does not present high demands on technical equipment and measuring method as other technical method like coherence measurement. When sing the method it is not necessary to measure simultaneously at the source and in living areas. The use of the method helps to assess the justification of complaints about noise and can be used in the design of technical noise control measures. was found that after a longer stay it is for some person possible to identify low-frequency noise the level of which lies deep, i.e. more than 10 dB, under the hearing threshold according to present international standards.
Nízkofrekvenční zvuk s frekvenčními složkami v pásmu kmitočtů nižších než 200 Hz má z hlediska svých fyzikálních vlastností při šíření vzduchem velmi nízký útlum a je velice málo ovlivňován překážkami. Šíří se tak na velké vzdálenosti a může způsobovat vznik stojatého vlnění, rezonance a výraznou nehomogenitu akustického pole, a to především v uzavřených prostorách. Během produkce elektronicky zesilované hudby ve venkovním prostředí má nízkofrekvenční zvuk navíc ještě i tonální charakter. Na základě těchto svých vlastností se může, zejména v noční době, stávat hlavní příčinou stížností obyvatel na hluk z venkovních produkcí hudby. Autoři na základě řady měření hluku z hudebních festivalů v období 2008 až 2010 předkládají poznatky, které jednoznačně ukazují na souvislost stížností obyvatel a působení nízkofrekvenční složky zvuku. Upozorňují na nevhodnost používání váhového filtru A při těchto měřeních, neboť dochází k výraznému potlačení právě frekvencí pod 1 kHz. Teprve použitím váhového filtru C a pomocí výpočtu rozdílu těchto hodnot lze objektivně indikovat i přítomnost nízkofrekvenčního zvuku. Autoři uvádějí příklady měření hluku z venkovní produkce hudby, včetně nízkofrekvenční složky ve venkovním prostoru i uvnitř budovy. Práce také předkládá poznatky o významných biologických aspektech vnímání hudby u člověka. Zdá se, že na jejich základě mohou hudební produkce a nízkofrekvenční zvuk vyvolávat u člověka řadu nepříjemných vjemů a pocitů. Autoři uvažují, že nízkofrekvenční zvuk může u člověka také ovlivňovat rytmy mozkové aktivity. Tím pak může být výrazně narušován spánek obyvatel i ve značných vzdálenostech od zdroje hudební produkce. Cílem práce je přispět k vysvětlení možných negativních účinků hluku z elektronicky zesilované hudby. Ukázat na nevhodnost některých současných zavedených postupů při měření a hodnocení tohoto hluku a navrhnout využití těchto poznatků pro snížení obtěžování a rušení obyvatel v okolí venkovních produkcí hudby.
Low frequency noise in the frequency range below 200 Hz has a very low attenuation through the open air, walls, windows and other barriers. It propagates over very large distances and can cause standing waves and resonances in dwellings. Therefore, the acoustic fields can be non homogenous in the embosomed areas. Some of the sources of low frequency noise are musical instruments. Presently, open air festivals have become a part of our everyday life, and sleep disturbance is commonly reported by people living in surrounding areas. The authors of the paper relate complaints of citizens from the surroundings of the open air festivals locations with low frequency noise in the music, based on series of measurements taken in the years 2008 and 2009. They point out the problems with measurements of the A-weighted sound level noise in which the low frequencies are present. They propose to use the difference between C- and A-weightings to indicate presence of the low frequency noise in the music. Examples of the outdoor and indoor noise measurements taken during the open air festivals are presented with categorization based on the types of music. Biological aspects of the influence of music on humans are also presented. It seems that loud music with low frequency noise can influence several systems in the human body. Special attention is paid to brain waves. Sleep disturbance of people living in distant dwellings is also worth concern. The aim of the presented work is to point out some negative effects of electronically amplified music at open air festivals on people living in the surrounding areas, and demonstrate the unsuitability of contemporary common measurement methods used in environmental noise investigation and health risk assessment.
- Klíčová slova
- veřejné zdraví, hodnocení zdravotních rizik, rušení, rušení spánku, stres, veřejná produkce hudby,
- MeSH
- environmentální zdraví MeSH
- fyziologický stres MeSH
- hluk škodlivé účinky MeSH
- hudba MeSH
- lidé MeSH
- počítačové zpracování signálu MeSH
- psychoakustika MeSH
- rizikové faktory MeSH
- sluchová percepce MeSH
- sluchový práh MeSH
- spánková deprivace MeSH
- veřejné zdravotnictví MeSH
- vnímání hlasitosti fyziologie MeSH
- vystavení vlivu životního prostředí analýza statistika a číselné údaje škodlivé účinky MeSH
- znečištění životního prostředí analýza statistika a číselné údaje škodlivé účinky MeSH
- zvuková spektrografie metody statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
BACKGROUND: Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) diminishes auditory hallucinations (AHs). The aims of our study were a) to assess the efficacy of LF-rTMS in a randomized, sham-controlled double-blind alignment, b) to identify the electrophysiological changes accompanying the LF-rTMS, and c) to identify the influence of LF-rTMS on brain functional connectivity (FC). METHODS: Nineteen schizophrenia patients with antipsychotic-resistant AHs were randomized to either active (n = 10) or sham (n = 9) LF-rTMS administered over the left temporo-parietal region for ten days. The clinical effect was assessed by the Auditory Hallucination Rating Scale (AHRS). The localization of the differences in electrical activity was identified by standardized low resolution brain electromagnetic tomography (sLORETA) and FC was measured by lagged phase synchronization. RESULTS: AHRS scores were significantly improved for patients receiving active rTMS compared to the sham (median reduction: 40 % vs 12 %; p = 0.01). sLORETA revealed a decrease of alpha-2, beta-1,-2 bands in the left hemisphere in the active group. Active rTMS led to a decrease of the lagged phase connectivity in beta bands originating in areas close to the site of stimulation, and to a prevailing increase of alpha-2 FC. No significant differences in current density or FC were observed in the sham group. LIMITATIONS: Limitations to our study included the small group sizes, and the disability of LORETA to assess subcortical neuronal activity. CONCLUSIONS: LF-rTMS attenuated AHs and induced a decrease of higher frequency bands on the left hemisphere. The FC changes support the assumption that LF-rTMS is linked to the modulation of cortico-cortical coupling.
Dementia is a growing issue in modern society. Non-pharmacological interventions such as music are suggested as the primary methods for symptom management. Therapeutic potential may also be found in sound/mechanical low frequency vibrations (LFV) that share the core characteristics of music, but these are lesser understood. The aim of the proposed scoping review is to explore the responses of persons with dementia to LFV, e.g., vibroacoustic therapy or whole-body vibration. The scoping review will follow the Joanna Briggs Institute methodology guidelines. An extensive search in BMC, CINAHL, Cochrane Central Register of Controlled Trials, EMBASE, ERIC, MEDLINE (OvidSP), Pedro, ProQuest Central, PsycINFO, Scopus, Web of Science, and grey literature sources in Clinical Trials, Current Controlled Trials, Google Scholar, and manual search of relevant journals is planned to find all relevant research papers. The paper selection, full-text assessment, and data extraction will be performed by two independent reviewers. Participants' responses to the interventions and the experiment designs, including methodological challenges, will be analysed and compared. Results may highlight potential gaps in reporting and comparing sound and mechanical vibration approaches and promote better understanding of their potential for managing the symptoms of dementia. Furthermore, the possible relationships between LFV and music-based interventions may become clearer.
- MeSH
- demence * terapie MeSH
- hudba * MeSH
- lidé MeSH
- systematický přehled jako téma * MeSH
- techniky fyzikální terapie MeSH
- vibrace MeSH
- výzkumný projekt MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The low frequency of nontuberculous mycobacterial infections, nonspecific symptoms for individual mycobacteria, and the lack of specific identification methods could alter correct diagnosis. This study presents a combined microbiology and molecular-based approach for Mycobacterium marinum detection in four aquarists with cutaneous mycobacterial infection. Simultaneously, ecology screening for M. marinum presence in the aquarists' fish tanks was performed. A total of 38 mycobacterial isolates originated from four human patients (n = 20), aquarium animals (n = 8), and an aquarium environment (n = 10). Isolate identification was carried out using 16S rRNA sequence analysis. A microbiology-based approach, followed by 16S rRNA sequence analysis, was successfully used for detection of M. marinum in all four patients. Animal and environmental samples were simultaneously examined, and a total of seven mycobacterial species were isolated: Mycobacterium chelonae , Mycobacterium fortuitum , Mycobacterium gordonae , Mycobacterium kansasii , Mycobacterium mantenii , Mycobacterium marinum , and Mycobacterium peregrinum . The presence of M. marinum was proven in the aquarium environments of two patients. Although M. marinum is described as being present in water, it was detected only in fish.
- MeSH
- antibakteriální látky farmakologie terapeutické užití MeSH
- atypické mykobakteriální infekce diagnóza farmakoterapie mikrobiologie patologie MeSH
- klarithromycin farmakologie terapeutické užití MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- mikrobiologie životního prostředí MeSH
- Mycobacterium marinum klasifikace účinky léků genetika izolace a purifikace MeSH
- Mycobacterium klasifikace genetika izolace a purifikace MeSH
- RNA ribozomální 16S genetika MeSH
- ryby mikrobiologie MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- práce podpořená grantem MeSH
The way the human brain represents speech in memory is still unknown. An obvious characteristic of speech is its evolvement over time. During speech processing, neural oscillations are modulated by the temporal properties of the acoustic speech signal, but also acquired knowledge on the temporal structure of language influences speech perception-related brain activity. This suggests that speech could be represented in the temporal domain, a form of representation that the brain also uses to encode autobiographic memories. Empirical evidence for such a memory code is lacking. We investigated the nature of speech memory representations using direct cortical recordings in the left perisylvian cortex during delayed sentence reproduction in female and male patients undergoing awake tumor surgery. Our results reveal that the brain endogenously represents speech in the temporal domain. Temporal pattern similarity analyses revealed that the phase of frontotemporal low-frequency oscillations, primarily in the beta range, represents sentence identity in working memory. The positive relationship between beta power during working memory and task performance suggests that working memory representations benefit from increased phase separation.SIGNIFICANCE STATEMENT Memory is an endogenous source of information based on experience. While neural oscillations encode autobiographic memories in the temporal domain, little is known on their contribution to memory representations of human speech. Our electrocortical recordings in participants who maintain sentences in memory identify the phase of left frontotemporal beta oscillations as the most prominent information carrier of sentence identity. These observations provide evidence for a theoretical model on speech memory representations and explain why interfering with beta oscillations in the left inferior frontal cortex diminishes verbal working memory capacity. The lack of sentence identity coding at the syllabic rate suggests that sentences are represented in memory in a more abstract form compared with speech coding during speech perception and production.
- MeSH
- dospělí MeSH
- elektrokortikografie MeSH
- krátkodobá paměť fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mozek fyziologie MeSH
- percepce řeči fyziologie MeSH
- řeč fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for depressive disorder, with outcomes approaching 45-55% response and 30-40% remission. Eligible predictors of treatment outcome, however, are still lacking. Few studies have investigated quantitative electroencephalography (QEEG) parameters as predictors of rTMS treatment outcome and none of them have addressed the source localization techniques to predict the response to low-frequency rTMS (LF rTMS). We investigated electrophysiological differences based on scalp EEG data and inverse solution method, exact low-resolution brain electromagnetic tomography (eLORETA), between responders and non-responders to LF rTMS in resting brain activity recorded prior to the treatment. Twenty-five unmedicated depressive patients (mean age of 45.7 years, 20 females) received a 4-week treatment of LF rTMS (1 Hz; 20 sessions per 600 pulses; 100% of the motor threshold) over the right dorsolateral prefrontal cortex. Comparisons between responders (≥50% reduction in Montgomery-Åsberg Depression Rating Scale score) and non-responders were made at baseline for measures of eLORETA current density, spectral absolute power, and inter-hemispheric and intra-hemispheric EEG asymmetry. Responders were found to have lower current source densities in the alpha-2 and beta-1 frequency bands bilaterally (with predominance on the left side) in the inferior, medial, and middle frontal gyrus, precentral gyrus, cingulate gyrus, anterior cingulate, and insula. The most pronounced difference was found in the left middle frontal gyrus for alpha-2 and beta-1 bands (p < 0.05). Using a spectral absolute power analysis, we found a negative correlation between the absolute power in beta and theta frequency bands on the left frontal electrode F7 and the change in depressive symptomatology. None of the selected asymmetries significantly differentiated responders from non-responders in any frequency band. Pre-treatment reduction of alpha-2 and beta-1 sources, but not QEEG asymmetry, was found in patients with major depressive disorder who responded to LF rTMS treatment. Prospective trials with larger groups of subjects are needed to further validate these findings.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Health information systems (HIS) are fundamental tools for the surveillance of health services, estimation of disease burden and prioritization of health resources. Several gaps in the availability of HIS for kidney disease were highlighted by the first iteration of the Global Kidney Health Atlas. METHODS: As part of its second iteration, the International Society of Nephrology conducted a cross-sectional global survey between July and October 2018 to explore the coverage and scope of HIS for kidney disease, with a focus on kidney replacement therapy (KRT). RESULTS: Out of a total of 182 invited countries, 154 countries responded to questions on HIS (85% response rate). KRT registries were available in almost all high-income countries, but few low-income countries, while registries for non-dialysis chronic kidney disease (CKD) or acute kidney injury (AKI) were rare. Registries in high-income countries tended to be national, in contrast to registries in low-income countries, which often operated at local or regional levels. Although cause of end-stage kidney disease, modality of KRT and source of kidney transplant donors were frequently reported, few countries collected data on patient-reported outcome measures and only half of low-income countries recorded process-based measures. Almost no countries had programs to detect AKI and practices to identify CKD-targeted individuals with diabetes, hypertension and cardiovascular disease, rather than members of high-risk ethnic groups. CONCLUSIONS: These findings confirm significant heterogeneity in the global availability of HIS for kidney disease and highlight important gaps in their coverage and scope, especially in low-income countries and across the domains of AKI, non-dialysis CKD, patient-reported outcomes, process-based measures and quality indicators for KRT service delivery.
OBJECTIVE: The goal of this study was to assess the activity of intracortical EEG sources in patients with OCD. METHODS: We compared resting state EEG from 50 OCD patients and 50 matched controls using standardized low-resolution electromagnetic tomography (sLORETA) and normative independent component analysis (NICA). Data were analyzed with 1 Hz frequency resolution. Group ICA was used to separate seven independent components from the control group data. The resulting weights and norms served to derive the same components from the OCD group and to compare their power with controls. RESULTS: In OCD, sLORETA indicated low-frequency power excess (2-6 Hz) in the medial frontal cortex, whereas group ICA showed increased low-frequency power in a component reflecting the activity of subgenual anterior cingulate, adjacent limbic structures and to a lesser extent also of lateral frontal cortex. CONCLUSIONS: Both methods provided evidence for medial frontal hyperactivation in OCD. SIGNIFICANCE: Our study is the first to use normative ICA in a clinical sample and indicates its potential utility as a diagnostic tool. The findings provide consistent results based on EEG source localization in OCD and are of practical interest for therapeutic interventions.
- MeSH
- dospělí MeSH
- elektroencefalografie MeSH
- lidé MeSH
- mozek patofyziologie MeSH
- obsedantně kompulzivní porucha diagnóza patofyziologie MeSH
- počítačové zpracování signálu MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This study examined the association between perceived control and several socioeconomic variables and self-rated health in seven post-communist countries (Russia, Estonia, Lithuania, Latvia, Hungary, Poland, Czech Republic). Questionnaire interviews were used to collect data on self-rated health in the last 12 months, education, marital status, perceived control based on nine questions, and material deprivation based on availability of food, clothing and heating. For each population, two ecological measures of material inequalities were available: an inequality score estimated from the survey data as the distance between the 90th and 10th percentiles of material deprivation, and Gini coefficient from published sources. Data on 5330 men and women aged 20-60 were analysed. Prevalence of poor health (worse than average) varied between 8% in Czechs and 19% in Hungarians. The age-sex-adjusted odds ratio for university vs primary education was 0.36 (0.26-0.49); odds ratios per 1 standard deviation increase in perceived control and in material deprivation were 0.58 (95% CI 0.48-0.69) and 1.51 (1.40-1.63), respectively. The odds ratio for an increase in inequality equivalent to the difference between the most and the least unequal populations was 1.49 (0.88-2.52) using the material inequality score and 1.41 (0.91-2.20) using the Gini coefficient. No indication of an effect of either inequality measure was seen after adjustment for individuals' deprivation or perceived control. The results suggest that, as in western populations, education and material deprivation are strongly related to self-rated health. Perceived control appeared statistically to mediate some of the effects of material deprivation. The non-significant effects of both ecological measures of inequality were eliminated by controlling for individuals' characteristics.
- MeSH
- chudoba MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- logistické modely MeSH
- manželský stav MeSH
- náhodné rozdělení MeSH
- odds ratio MeSH
- příjem MeSH
- průřezové studie MeSH
- průzkumy a dotazníky MeSH
- psychosociální deprivace MeSH
- rozhovory jako téma MeSH
- sociální podmínky * MeSH
- socioekonomické faktory MeSH
- výchova a vzdělávání MeSH
- zdravotní stav * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Česká republika MeSH
- Estonsko MeSH
- Litva MeSH
- Lotyšsko MeSH
- Maďarsko MeSH
- Polsko MeSH
- Rusko MeSH
