781 research outputs found
Modulation of the sympatho-vagal balance during sleep
No full textSleep is a complex state characterized by important changes in the autonomic modulation of the cardiovascular activity. Heart rate variability (HRV) greatly changes during different sleep stages, showing a predominant parasympathetic drive to the heart during non-rapid eye movement sleep (NREM) and an increased sympathetic activity during rapid eye movement sleep (REM).Respiration undergoes important modifications as well, becoming deeper and more regular with deep sleep and shallower and more frequent during REM. The aim of the present study is to assess both autonomic cardiac regulation and cardiopulmonary coupling variations during different sleep stages in healthy subjects, using spectral and cross-spectral analysis of the HRV and respiration signals. Polysomnographic sleep recordings were performed in 11 healthy women and the HRV signal and the respiration signal were obtained. The spectral and cross-spectral parameters of the HRV signal and of the respiration signal were computed at low frequency (LF) and at breathing frequency (high frequency, HF) during different sleep stages. Results attested a sympatho-vagal balance shift towards parasympathetic modulation during NREM sleep and towards sympathetic modulation during REM sleep. Spectral analysis of the HRV signal and of the respiration signal indicated a higher respiration regularity during deep sleep, and a higher parasympathetic drive is also confirmed by an increase in the coherence between the HRV and the respiration signal in the HF band during NREM sleep. Our findings about sleep stage-dependent variations in the HRV signal and in the respiratory activity are in line with previous evidences and confirm spectral analysis of the HRV and the respiration signal to be a suitable tool for investigating cardiac autonomic modulation and respiration activity during sleep
A NIRS STUDY OF THE HEMODYNAMIC CORRELATES OF COGNITIVEFUNCTIONS
No full textSustained attention (SA) is a function within the construct of attention, defined as the ability to
maintain a consistent level of vigilance and detect unpredictably occurring stimuli over time [1].
Working memory (WM) is a component of memory which encompasses the temporary on-line
maintenance of information and its manipulation [2].
Neuroimaging studies converge to suggest a prominent role of the prefrontal cortex (PFC) in processes
affecting both SA (primarily in the right hemisphere) and WM [2].
Enhanced brain activity associated with cognitive effort induces an increased metabolic consumption
which leads to local hemodynamic changes that modify the optical properties of the cerebral tissue.
Near Infrared Spectroscopy (NIRS) is an optical imaging method that capitalizes on the absorption and
scattering properties of near-infrared light to monitor the hemodynamic changes occurring in response
to functional activation [3]. NIRS has advantages over more common imaging methods including noninvasivity,
portability, better motion tolerance and increased comfort for the participants and is being
widely used to investigate cortical activation related to cognitive processes [3].
One of the most popular WM experimental paradigms is the n-back task, in which participants are
required to monitor a series of stimuli and to respond whenever the currently presented stimulus is the
same as the one presented n trials before [4]. In the 0-back condition the target stimulus is previously
specified and the task is therefore expected to elicit the activation of SA mechanisms to maintain high
vigilance and receptivity levels over time and promptly respond to task-relevant stimuli. In the other
conditions (1-, 2-, ..., n-back) the task requires not only continuous vigilance, but also the storage,
updating and manipulation of newly presented information and is therefore assumed to place great
demands on key processes within WM, inasmuch as the cognitive load increases.
The aims of the present study are to use NIRS to evaluate PFC activation during SA and WM
processes and to investigate the relationships between the cognitive load variation and the cortical
activation patterns
Automatic arrhythmia detection based on heart beat interval series recorded through bed sensors during sleep
No full textA high frequency of cardiac arrhythmias has been reported in sleep disordered patients. In order to detect the presence of arrhythmia during sleep, cardiac activity needs to be monitored. Several devices exist able to provide reliable Heart Rate Variability (HRV) measures in a minimally-intrusive way. Hence, there is the need for the development of robust methods for arrhythmia detection based on HRV measures. In the present study a method for automatic arrhythmia detection based on the analysis of an inter-beat series was developed and validated on recordings coming from the MIT-BIH Arrhythmia Database. The method was also applied on a beat to beat interval series obtained from the ballistocardiographic (BCG) signal of one subject, which was recorded during sleep using an innovative bed sensor which allowed for a noncontact and unobtrusive recording. When compared to the results of arrhythmia detection performed on the electrocardiographic (ECG) signal (concurrently acquired using polysomnography) using Cardioline Cube HOLTER analysis software, our method achieved a sensitivity of 55.6%, a specificity of 94.7% and an accuracy of 91.8%. Our results suggest that the bed sensor could represent a reliable tool to assist the clinician in arrhythmia detection. (13 refs.
Riflessioni linguistiche sul tedesco e sul russo in Julya Rabinowich: un confronto tra narrazione autobiografica orale e il romanzo Spaltkopf
No full textLinguistic Reflections in German and Russian in Julya Rabinowich: A Comparative
Study of Oral Autobiographical Narrative and the Novel Spaltkopf.
The Austrian author Julya Rabinowich, born in Leningrad in 1970 to a family of Rus-
sian Jews and emigrated to Vienna at the age of 7, is one of the most renowned repre-
sentatives of contemporary literature in the German language. Rabinowich made her
literary debut in 2008 with Spaltkopf (Split Head), her most strongly autobiographical
novel. In 2012, the writer was interviewed by Michaela Bürger-Koftis as part of the
research project Polyphonie. Mehrsprachigkeit_Kreativität_Schreiben. This interview
can be understood as a linguistic biography, as Rabinowich recounts her experiences
related to the languages in her linguistic repertoire, focusing particularly on German
and Russian. From this account, the author’s Spracheinstellungen (linguistic attitudes),
as well as the impressions and emotions related to her two main languages, emerge.
The aim of this study is to compare the interview passages in which Rabinowich
expresses herself regarding German and Russian with excerpts from Spaltkopf where
the relationship of the protagonist, Mischka, with these two languages emerges. In this
162 Michaela Bürger-Koftis, Ramona Pellegrino
way, it will be possible to determine whether Spaltkopf reflects not only the author’s
migratory experience but also her linguistic biography. Furthermore, it will be analyz-
ed if and to what extent the expression of linguistic attitudes and emotions related to
German and Russian differs between the novel and the oral autobiographical account.
To examine how Rabinowich expresses her linguistic experiences and emotions relat-
ed to German and Russian, a qualitative analysis of the texts will be conducted, with
a theoretical approach based on the concepts of linguistic biography and verbalization
of emotions developed by Brigitta Busch and Reinhard Fiehler
Ramona Bennett, Tacoma, October 1976
No full textRamona Bennett (b. 1938) is a prominent Puyallap Tribe leader and activist. She was elected to the Puyallup Tribal Council in 1968, and served as Tribal Chairwoman from 1971 to 1978. Bennett is also a pioneer of fishing rights advocacy, co-founding the Survival of American Indians Association in 1964, and helping to bring “fish-in” protests to national prominence.
Much of Bennett’s work focuses on social welfare issues, mainly fighting for the rights of women, children and families. She began her social service work in the 1950s, with the Seattle’s American Indian Women’s Service League. In 1972, she co-founded the Local Indian Child Welfare Act Committee, where she developed a model for childhood and family services that she used to co-author and secure the national Indian Child Welfare Act of 1978, a Federal law that governs the removal and out-of-home placement of indigenous children. In the 1980s, she co-founded the Rainbow Youth and Family Services in Tacoma, a non-profit which she ran for many years.
This photo of Ramona Bennett was taken for a profile of her run by the Seattle Post-Intelligencer in October 1976. At the time, Bennett was chairwoman of the Puyallup Tribal Council.Caption information source: “Ramona Bennett,” The Seattle Civil Rights & Labor History Project, University of Washington, https://depts.washington.edu/civilr/bennett.htm
Caption information source: "Ramona Bennett - a Cool, Witty, Charming Leader" by Jack Wilkins, Seattle Post=Intelligencer, October 28, 1976, p. A71 photographic print: b&w; 8 x 10 in
Portrait of Helen Fiske Hunt Jackson, author of Ramona, [s.d.]
No full textPhotographic portrait of Helen Fiske Hunt Jackson, author of "Ramona", [s.d.]. Mrs. Jackson is pictured standing, wearing an elaborate dress with a huge bustle, made of what appears to be silk or satin. Her hands are folded across her waist while she looks to the right. She appears to be in her middle-age and wears the large locks of her curly hair pulled back from her face. She can be seen smiling, while a chair supports her dress to the right. Picture file card reads: "An American novelist, poet, and general writer, born at Amherst, mass. October 18, 1831; died at San Francisco, CA, August 12, 1885. She was the daughter of Professor Fiske, of Amherst. He first husband, Capt. E.B. Hunt, died in 1863. In 1870, she published a volume entitled "Verses". Her first prose volume, "Bits of Travel" (1872), was followed by "Bits of Talk About Home Matters" (1873), and "Bits of Travel at Home" (1878). In 1875 she married Mr. W.S. Jackson, of Colorado Springs. Here, she published "A Century of Dishonor", relating to the dealings of the U.S. Government with the Indians. This led to her appointment in 1883 as a special commissioner to examine into the condition and needs of the Mission Indians. After visiting the different tribes, she wrote "Ramona"(1884), a novel relating to the Mission Indians. Mrs. Jackson had previously written two novels in the "no Name" seires: "Mercy Philbric's Chioce" ["Choice"?] (1876) and "Hetty's Strange History"(1877). Besides these works, she published "The Story of Boon", a poem (1879), the training of children(1882), and several books for young people: "Nellie's Silver Mine" (1878), "Mammy Tittleback and her Family" (1881), and "The Hunter Cats of Connorloa" (1884). Since her death have appeared "Glimpses of Three Coasts", "Sonnets and Lyrics", "Zeph", a novel (1886), and "Between Whiles" (1887)"
Social media communication strategies in fashion industry
No full textThis study quasi-replicates a previous work based on social communication strategies in the insurance sector, analyzing what happens in the Italian fashion industry. Our sample yields findings dissimilar to the earlier research and suggests new insights
The CardioRisk project: Improvement of cardiovascular risk assessment
No full textThe CardioRisk project addresses the coronary artery disease (CAD), namely, the management of myocardial infarction (MI) patients. The main goal is the development of personalized clinical models for cardiovascular (CV) risk assessment of acute events (e.g., death and new hospitalization), in order to stratify patients according to their care needs. This paper presents an overview of the scientific and technological issues that are under research and development.Three major scientific challenges can be identified: (i) the development of fusion approaches to merge CV risk assessment tools; (ii) strategies for the grouping (clustering) of patients; (iii) biosignal processing techniques to achieve personalized diagnosis. At the end of the project, a set of algorithms/models must properly address these three challenges.Additionally, a clinical platform was implemented, integrating the developed models and algorithms. This platform supports a clinical observational study (100 patients) that is being carried out in Leiria Hospital Centre to validate the developed approach. Inputs from the hospital information system (demographics, biomarkers, clinical exams) are considered as well as an ECG signal acquired based on a Holter device. A real patient dataset provided by Santa Cruz Hospital, Portugal, comprising N = 460 ACS-NSTEMI patients is also applied to perform initial validations (individual algorithms).The CardioRisk team is composed by two research institutions, the University of Coimbra (Portugal), Politecnico di Milano (Italy) and Leiria Hospital Centre (a Portuguese public hospital
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