932 research outputs found
Present and past selves : a steady-state visual evoked potentials approach to self-face processing
The self-face has a prioritized status in the processing of incoming visual inputs. As the self-face changes over the lifespan, this stimulus seems to be well-suited for investigation of the self across time. Here, steady-state visual evoked potentials (SSVEP, oscillatory responses to periodic stimulation with a frequency that mirrors the frequency of stimulation) were used to investigate this topic. Different types of faces (present self, past self, close-other's, unknown, scrambled) flickered four times per second in two types of stimulation (‘identical', with the same image of a given type of face; ‘different', with different images of the same type of face). Each of the 10 stimulation sessions lasted 90 seconds and was repeated three times. EEG data were recorded and analyzed in 20 participants. In general, faces evoked higher SSVEP than scrambled faces. The impact of identical and different stimulation was similar for faces and scrambled faces: SSVEP to different stimuli (faces, scrambled faces) was enhanced in comparison to identical ones. Present self-faces evoked higher SSVEP responses than past self-faces in the different stimulation condition only. Thus, our results showed that the physical aspects of the present and past selves are differentiated on the neural level in the absence of an overt behavior
Calibrating spatial interaction models from GPS tracking data: an example of retail behaviour
Global Positioning System (GPS) technology has changed the world. We now depend on it for navigating vehicles, for route finding and we use it in our everyday lives to extract information about our locations and to track our movements. The latter use offers a potential alternative to more traditional sources of movement data through the construction of trip trajectories and, ultimately, the construction of origin-destination flow matrices. The advantage of being able to use GPS-derived movement data is that such data are potentially much richer than traditional sources of movement data both temporally and spatially. GPS-derived movement data potentially allow the calibration of spatial interaction models specific to very short time intervals, such as daily or even hourly, and for user-specified origins and destinations. Ultimately, it should be possible to calibrate continuously updated models in near real-time. However, the processing of GPS data into trajectories and then origin-destination flow matrices is not straightforward and is not well understood. This paper describes the process of transferring GPS tracking data into matrices that can be used to calibrate spatial interaction models. An example is given using retail behaviour in two towns in Scotland with an origin-constrained spatial interaction model calibrated for each day of the week and under different weather conditions (normal, rainy, windy). Although the study is small in terms of individuals and spatial context, it serves to demonstrate a future for spatial interaction modelling free from the tyranny of temporally static and spatially predefined data sets
Zespół policystycznych jajników (PCOS), a ryzyko występowania cukrzycy ciążowej (GDM)
Gestational diabetes mellitus (GDM) is a common complication of pregnancy. In the course of pregnancy, elevated
levels of hormones and other proteins having insulin-antagonistic effects lead to higher insulin resistance in peripheral
tissues, followed by hyperinsulinemia. Risk factors for the development of GDM have been well-established.
However, the debate whether polycystic ovary syndrome (PCOS) may predispose to GDM continues. Patients with
PCOS are often affected by obesity, dyslipidemia, hyperinsulinemia ,and tissue-specific insulin resistance. Obesity
occurs in 50% of the cases, while tissue-specific insulin resistance is observed in 20-40% of the affected patients.
This paper aims at systematizing risk factors that could contribute to the development of GDM, as well as reviewing
literature reports and analyses on the occurrence of a potential correlation.Cukrzyca ciążowa (gestational diabetes mellitus – GDM) jest częstym stanem patologicznym wikłającym ciążę.
W przebiegu ciąży dochodzi do zwiększenia stężenia w organizmie hormonów oraz innych białek o działaniu
antagonistycznym w stosunku do insuliny, co prowadzi do wzrostu insulinooporności tkanek obwodowych, a
następnie do hiperinsulinemii. Pomimo, że znane są czynniki ryzyka prowadzące do rozwoju GDM, od lat toczy się
dyskusja czy zespół policystycznych jajników (PCOS) może predysponować do wystąpienia cukrzycy ciążowej. U
pacjentek z PCOS często występuje otyłość, dyslipidemia, hiperinsulinemia oraz brak wrażliwości tkankowej na
insulinę. Otyłość występuje u 50% przypadków, a brak wrażliwości na insulinę u 20-40% pacjentek.
Celem poniższego opracowania jest usystematyzowanie czynników ryzyka, które mogłyby u pacjentek z PCOS
prowadzić do rozwoju GDM, a także przegląd badań oraz analiz dotyczących występowania potencjalnej korelacji
Investigation into Polyphenol Profile and Biological Activities of Enriched Persimmon/Apple Smoothies during Storage
Smoothies are becoming an increasingly popular product as a healthy alternative to snacks. The consumer expects from this product that, apart from its nutritional value, it will also be qualitatively stable during storage. Therefore, in this study, original smoothies obtained with persimmon fruit puree and apple juice (Dk/Md) enriched with Arbutus unedo fruits, Myrtus communis purple berry extract, Acca sellowiana, and Crocus sativus petal juice were evaluated for their polyphenol composition, antioxidant activity, and inhibition on targeted digestive enzymes, over six months of storage. The amount of polyphenols evaluated by UPLC-PDA analysis decreased in six months from 23.5% for both Dk/Md and enriched C. sativus smoothies to 42.5% for enriched A. sellowiana, with anthocyanins the most sensitive compounds (71.7–100% loss). Values of antioxidant assays generally strongly decreased during the first three months (up to ca. 60%) and to a lesser extent in the following three months (0.4–27%). In addition, inhibitory activity on α-amylase, α-glucosidase, and pancreatic lipase, especially on the last two enzymes, was negatively affected by time storage. The outcome of this study indicates that persimmon fruit is a good option for producing smoothies, and enrichment with other plant extracts can enhance the bioactive compound content and biological activities. It is recommended that appropriate storage strategies to preserve the properties of those smoothies should be developed
Knowing when to stop: Aberrant precision and evidence accumulation in schizophrenia
Predictive coding and active inference formulations of the dysconnection hypothesis suggest that subjects with schizophrenia (SZ) hold unduly precise prior beliefs to compensate for a failure of sensory attenuation. This implies that SZ subjects should both initiate responses prematurely during evidence-accumulation tasks and fail to inhibit their responses at long stop-signal delays. SZ and healthy control subjects were asked to report the timing of billiards-ball collisions and were occasionally required to withhold their responses. SZ subjects showed larger temporal estimation errors, which were associated with premature responses and decreased response inhibition. To account for these effects, we used hierarchical (Bayesian) drift-diffusion models (HDDM) and model selection procedures to adjudicate among four hypotheses. HDDM revealed that the precision of prior beliefs (i.e., starting point) rather than increased sensory precision (i.e., drift rate) drove premature responses and impaired response inhibition in patients with SZ. From the perspective of active inference, we suggest that premature predictions in SZ are responses that, heuristically, are traded off against accuracy to ensure action execution. On the basis of previous work, we suggest that the right insular cortex might mediate this trade-off
Risk factors for cesarean section after using the Foley catheter for labor induction
Objective: The aim of the study was to investigate the value of the Bishop score and ultrasound examination of the cervix in predicting the success of labor induction with the use of the Foley catheter determined by the mode of delivery. Material and methods: Foley catheter induction of labor was performed in 135 pregnancies between 38 to 42 weeks gestation. The study group was divided into two groups, depending of the mode of delivery: vaginal vs. cesarean. Results: The Bishop score was significantly higher in the vaginal delivery group when compared to the caesarean section group (5.2; 95%CI: 4.4 – 6.2 vs. 3.9; 95%CI: 2.8-4.9). Cervical length was not statistically significantly different between the two groups. Multivariate logistic regression showed that patient-specific risk for caesarean section decreases with increasing maternal age and the Bishop score (Detection Rate [DR] of 52% at fixed False Positive Rate [FPR] of 10%). Conclusions: Failure of labor induction with the use of the Foley catheter can be predicted by maternal age and pre-induction Bishop score
A possible role of tachykinin-related peptide on an immune system activity of mealworm beetle, Tenebrio molitor L.
Tachykinin-related peptides (TRPs) are important neuropeptides. Here we show that they affect the insect immune system, especially the cellular response. We also identify and predict the sequence and structure of the tachykinin-related peptide receptor (TRPR) and confirm the presence of expression of gene encoding TRPR on Tenebrio molitor haemocytes. After application of the Tenmo-TRP-7 in T. molitor the number of circulating haemocytes increased and the number of haemocytes participating in phagocytosis of latex beads decreased in a dose- and time-dependent fashion. Also, Tenmo-TRP-7 affects the adhesion ability of haemocytes. Six hours after injection of TenmoTRP-7, a decrease of haemocyte surface area was observed under both tested Tenmo-TRP-7 concentrations (10-7 and 10-5 M). The opposite effect was reported 24 h after injection, which indicates that the influence of Tenmo-TRP-7 on modulation of haemocyte behaviour differs at different stages of stress response. Tenmo-TRP-7 application also resulted in increased phenoloxidase activity 6 and 24 h after injection. The assessment of DNA integrity of haemocytes showed that the injection of Tenmo-TRP-7 at 10-7 M led to a decrease in DNA damage compared to control individuals. This effect was only visible 6 h after Tenmo-TRP-7 application. After 24 h, Tenmo-TRP-7 injection increased DNA damage. We also confirmed the expression of immune-related genes in nervous tissue of T. molitor. Transcripts for genes encoding receptors participating in pathogen recognition processes and antimicrobial peptides were detected in T. molitor brain, retrocerebral complex and ventral nerve cord. These results may indicate a role of the insect nervous system in pathogen recognition and modulation of immune response similar to vertebrates. Taken together, our results support the notion that tachykinin-related peptides probably play an important role in the regulation of the insect immune system. Moreover, some resemblances with action of tachykininrelated peptides and substance P showed that insects can be potential model organisms for analysis of hormonal regulation of conserved innate immune mechanisms
The use of carbon monoxide as a probe molecule in spectroscopic studies for determination of exposed gold sites on TiO2
The sol immobilisation technique, in which a stabilising ligand (such as polyvinyl alcohol or polyvinyl pyridine) can be used to tune metal particle size and composition, has become a valuable method of making supported nanoparticle catalysts. An unfortunate consequence of the stabilising ligand is that often access of reactant molecules to the metal nanoparticle surface is impeded. Several methods have been proposed for the removal of these ligands, though determination of the degree of their success is difficult. Here, we demonstrate the use of in situ infrared and UV-Vis spectroscopy to elucidate the access of carbon monoxide to the surface of Au/TiO2 catalysts before and after various ligand removal treatments. These were contrasted with a catalyst prepared by deposition precipitation prepared in the absence of stabilising ligand as a control. Changes were observed in the infrared spectrum, with the wavenumber of carbon monoxide linearly bonded to Au for catalysts shifting before and after ligand removal, which correlated well with the activity of the catalyst for carbon monoxide oxidation. Also the extent of shifting of the Au surface resonance plasmon band on the addition of carbon monoxide, observed by UV-Vis, also correlated well with catalyst activity. These simple methods can be used to determine the quantity of exposed metal sites after a ligand removal treatment and so determine the treatments effectiveness
- …