67 research outputs found
Oscillatory mechanisms of conscious perception and attention
Although the prominent role of neural oscillations in perception and cognition has been continuously investigated, some critical questions remain unanswered. My PhD thesis was aimed at addressing some of them.
First, can we dissociate oscillatory underpinnings of perceptual accuracy and subjective awareness? Current work would strongly suggest that this dissociation can be drawn. While the fluctuations in alpha-amplitude decide perceptual bias and metacognitive abilities, the speed of alpha activity (i.e., alpha-frequency) dictates sensory sampling, shaping perceptual accuracy.
Second, how are these oscillatory mechanisms integrated during attention? The obtained results indicate that a top-down visuospatial mechanism modulates neural assemblies in visual areas via oscillatory re-alignment and coherence in the alpha/beta range within the fronto-parietal brain network. These perceptual predictions are reflected in the retinotopically distributed posterior alpha-amplitude, while perceptual accuracy is explained by the higher alpha-frequency at the to-be-attended location. Finally, sensory input, elaborated via fast gamma oscillations, is linked to specific phases of this slower activity via oscillatory nesting, enabling integration of the feedback-modulated oscillatory activity with sensory information.
Third, how can we relate this oscillatory activity to other neural markers of behaviour (i.e., event-related potentials)? The obtained results favour the oscillatory model of ERP genesis, where alpha-frequency shapes the latency of early evoked-potentials, namely P1, with both neural indices being related to perceptual accuracy. On the other hand, alpha-amplitude dictates the amplitude of later P3 evoked-response, whereas both indices shape subjective awareness.
Crucially, by combining different methodological approaches, including neurostimulation (TMS) and neuroimaging (EEG), current work identified these oscillatory-behavior links as causal and not just as co-occurring events. Current work aimed at ameliorating the use of the TMS-EEG approach by explaining inter-individual differences in the stimulation outcomes, which could be proven crucial in the way we design entrainment experiments and interpret the results in both research and clinical settings
The aestheticization of Yugoslav architecture through structuralist analysis of form meaning relationship
This paper addresses the aestheticization of Yugoslav architecture through the
implementation of structuralist form that took place between the early 1950s and
the late 1970s, and calls attention to the need for contemplating the relationship
between formal and intrinsic elements in architecture. An important component
of the interest for the formal issues of architecture was to make a distance from
functionalistic philosophy, which led to novel understanding of form and to the
aestheticization of architecture. Structuralist aesthetics, which was accepted in the
1950s, changed the concept of form for the concept of structure, and focused on the
elucidation of internal construction and organization. With reference to structuralist
theoretic-methodological approach, an aspiration of Yugoslav architects for
achieving inter-relationship between physical and semiotic structure via invisible
laws that define and form elements of structure is pointed out. Different aspects
of aesthetics of Yugoslav architecture reflected in various approaches for accepting
the formal principles: the recognition of constructive aesthetics and importance of
integration of constructive and formal elements of an organic entity, the interest in
relations between the elements of architectural system, the idea of fluid space, and
the evolutionary growth, development and transformation. This paper starts from
the premise that the aspiration for aestheticization of architectural form through
articulation of the unity of elements promoted Yugoslav architecture to build a
connection between formal structure of an object and the meaning of its structural
elements
An Observational Study of Engineering Online Education During the COVID-19 Pandemic
Although online education has become a viable and major component of higher
education in many fields, its employment in engineering disciplines has been
limited. COVID-19 pandemic compelled the global and abrupt conversion of
conventional face-to-face instruction to the online format. The negative impact
of such sudden change is undeniable. Urgent and careful planning is needed to
mitigate pandemic negative effects on engineering education, especially for
vulnerable, disadvantaged, and underrepresented students who have to deal with
additional challenges (e.g. digital equity gap). To enhance engineering online
instruction during the pandemic era, we conducted an observational study at
California State University, Long Beach (a minority-serving institution). 110
faculty and 627 students from six engineering departments participated in our
surveys and answered quantitative and qualitative questions to highlight the
challenges they experienced during the online instruction in Spring 2020. In
this work, we present the results of these surveys in detail and propose
solutions to address the identified issues including logistical, technical,
learning/teaching challenges, assessment methods, and hands-on training. As the
pandemic continues, sharing these results with other educators can help with
more effective planning and choice of best practices to improve the online
engineering education during COVID-19 and beyond.Comment: 10 pages, 3 figures, 2 table
Biophilic architecture: nature-based design solutions for health and well-being in living spaces
This research focuses on improving the well-being and health of citizens in
terms of the design and development of living spaces in harmony with nature. In
the contemporary moment, most cities suffer from health and environmental
problems. Also, the growing awareness of climate change issues makes it even more
apparent and essential to bring nature into our living spaces. Scientific studies have
pointed out on a multiplicity of benefits of nature for people, especially for children
and older populations. Bringing nature indoor causes increased participation in
physical activities, improved mental health and cognitive function and an increase
in social interaction between people. Nature and its elements have great power
on the human body. The concept of biophilia advocates that there is an innate
connection between humans and nature and that people tend to show a positive
response when they experience a connection with nature. Accordingly, biophilic
design is the design of spaces that promotes and encourages the interaction of
humans with nature and natural systems. This paper researches different design
methodologies, strategies, principles, scales, and concepts according to patterns of biophilic design and with a focus on their influence on the health and well-being of
users. The research also opens further discussions about the potentials of sensitive
and responsive biophilic design to improve the health and environmental problems of
contemporary urban areas
Transcranial magnetic stimulation effects support an oscillatory model of ERP genesis
Whether prestimulus oscillatory brain activity contributes to the generation of post-stimulus-evoked neural responses has long been debated, but findings remain inconclusive. We first investigated the hypothesized relationship via EEG recordings during a perceptual task with this correlational evidence causally probed subsequently by means of online rhythmic transcranial magnetic stimulation. Both approaches revealed a close link between prestimulus individual alpha frequency (IAF) and P1 latency, with faster IAF being related to shorter latencies, best explained via phase-reset mechanisms. Moreover, prestimulus alpha amplitude predicted P3 size, best explained via additive (correlational and causal evidence) and baseline shift mechanisms (correlational evidence), each with distinct prestimulus alpha contributors. Finally, in terms of performance, faster prestimulus IAF and shorter P1 latencies were both associated with higher task accuracy, while lower prestimulus alpha amplitudes and higher P3 amplitudes were associated with higher confidence ratings. Our results are in favor of the oscillatory model of ERP genesis and modulation, shedding new light on the mechanistic relationship between prestimulus oscillations and functionally relevant evoked components
Changing connectivity between premotor and motor cortex changes inter-areal communication in the human brain.
The ventral premotor cortex (PMv) is an important component of cortico-cortical pathways mediating prefrontal control over primary motor cortex (M1) function. Paired associative stimulation (ccPAS) is known to change PMv influence over M1 in humans, which manifests differently depending on the behavioural context. Here we show that these changes in influence are functionally linked to PMv-M1 phase synchrony changes induced by repeated paired stimulation of the two areas. PMv-to-M1 ccPAS leads to increased phase synchrony in alpha and beta bands, while reversed order M1-to-PMv ccPAS leads to decreased theta phase synchrony. These changes are visible at rest but are predictive of changes in oscillatory power in the same frequencies during movement execution and inhibition, respectively. The results unveil a link between the physiology of the motor network and the resonant frequencies mediating its interactions and provide a putative mechanism underpinning the relationship between synaptic efficacy and brain oscillations
Automated generation of custom processor core from C code
We present a method for construction of application-specific processor cores from a given C code. Our approach consists of three phases. We start by quantifying the properties of the C code in terms of operation types, available parallelism, and other metrics. We then create an initial data path to exploit the available parallelism. We then apply designer-guided constraints to an interactive data path refinement algorithm that attempts to reduce the number of the most expensive components while meeting the constraints. Our experimental results show that our technique scales very well with the size of the C code. We demonstrate the efficiency of our technique on wide range of applications, from standard academic benchmarks to industrial size examples like the MP3 decoder. Each processor core was constructed and refined in under a minute, allowing the designer to explore several different configurations in much less time than needed for manual design. We compared our selection algorithm to the manual selection in terms of cost/performance and showed that our optimization technique achieves better cost/performance trade-off. We also synthesized our designs with programmable controller and, on average, the refined core have only 23% latency overhead, twice as many block RAMs and 36% fewer slices compared to the respective manual designs
Easy-to-apply chemical pre-treatment for long lasting bonding with typical adhesives on industrial polyolefins
Is Balint training associated with the reduced burnout among primary health care doctors?
The aim of our study was to examine whether the participation in Balint group is associated with the reducing burnout syndrome among primary health care doctors. This investigation was conducted on a population of 210 doctors employed in primary health centers in Belgrade. Out of 210 doctors, 70 have completed Balint training for a period of at least 1 year, whereas 140 doctors have never attended this training (the Non-Balint group). The level of burnout among physicians was assessed with the Serbian translation of the original 22- item version of the Maslach Burnout Inventory – Human Services Survey which defines burnout in relation to emotional exhaustion, depersonalization and personal accomplishment. We found that 45.0% of the Non-Balint participants and 7.1% of the Balint-trained participants responded with symptoms of high level of emotional exhaustion, with a statistically significant difference (p < 0.001). In relation to depersonalization, 20% of the Non-Balint subjects were highly depersonalized compared to 4.4% of the Balint-trained subjects, with a statistically significant difference (p < 0.001). Regarding the personal accomplishment, 21.4% of the Non-Balint subjects and 7.1% of the Balint-trained subjects had a perception of low personal accomplishment, with a statistical significance (p < 0.001). In the multiple ordinal logistic model, with emotional exhaustion as a dependent variable, statistically significant predictor was female gender (OR = 2.51; p = 0.021), while Balint training was obtained as a protective factor (OR = 0.12; p < 0.001). Non-specialists were detected as a risk factor for depersonalization (OR = 2.14; p = 0.026) while Balint group was found as a protective factor (OR = 0.10; p < 0.001), according to the multiple ordinal logistic regression analysis. Regarding the reduced personal accomplishment, our results indicated that nonspecialists were at risk for this subdimension (OR = 2.09; p = 0.025), whereas Balint participants were protected (OR = 0.18; p < 0.001). Participation in Balint groups is associated with the reduced burnout syndrome among primary health care doctors.Keywords: Doctor-patient relationship; Balint groups; burnout; primary health care; patientcentered; approac
Predictors of poor neonatal outcomes in fetuses diagnosed with congenital urinary tract anomalies
Objectives: Urinary tract anomalies account for approximately one-quarter of all antenatally detected anomalies. The aim of this study was to identify factors associated with severe adverse neonatal outcomes of a prenatally diagnosed urinary tract anomaly.Material and methods: A retrospective-prospective study included 101 pregnant women with prenatally diagnosed fetal urinary tract anomalies presented to the Council for Fetal Anomalies. Prenatal diagnoses were compared with autopsy findings in cases of terminated pregnancy or with clinical and operative findings of the infants.Results: The mortality rate in the group of patients with fetal obstructive uropathy (60 patients) was 10% and in the group of patients with fetal multicystic dysplastic kidney (38 patients) 15.7%. Surgery was performed on 53.4% of the children, whereas more than half of the operations involved resolving associated urinary tract anomalies. Postoperative renal function deterioration occurred in 19% of the children.Conclusions: The prognosis of renal function in obstructive uropathies is excellent if oligoamnios does not develop prenatally and in case of timely provided surgical care is provided postnatally. The finding of the bilateral multicystic dysplastic kidney is associated with poor prognosis. The prognosis in fetal unilateral multicystic dysplastic kidney depends primarily on the condition of the contralateral kidney and the existence of associated anomalies
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