175 research outputs found
Jono Šliūpo filosofinės kūrybos recepcija
1991 m. gegužės 21 d. Lietuvos Mokslų akademijos Filosofijos, sociologijos ir teisės institute mokslinė bendradarbė Gražina Ona Pranckietytė apgynė filosofijos kandidato disertaciją „Jono Šliūpo filosofinė kūryba“. Disertacijos mokslinis vadovas – prof. R. Plečkaitis, oficialieji oponentai: J. Balčius ir J. Mureika. Disertacijoje nagrinėjama J. Šliūpo filosofinė evoliucija, išskiriami trys kūrybos ir veiklos tarpsniai, analizuojamos ontologinės ir gnoseologinės nuostatos, jo socialinių pažiūrų struktūra, evoliucija ir pobūdis, etinė koncepcija
Neomonadologinė gamtos mokslų pasaulėvaizdžio interpretacija
1993 m. gruodžio 29 d. Filosofijos, sociologijos ir teisės institute S. Kanišauskas apgynė filosofijos daktaro disertaciją „Žmogaus ir kosmoso ryšiai šiuolaikiniuose gamtos moksluose. Filosofiniai aspektai“. Doktorantūros studijų vadovas – prof. A. Krikštopaitis, oficialieji oponentai: prof. A. Merkys, doc. V. Radvilavičius, dr. G. Kakaras. Disertacijoje nagrinėjami įvairūs reliatyvistinių kosmologijų pasaulėvaizdžiai, gyvybės ir proto visatoje bei pačios visatos evoliucijos problemos, postuluojama hipotezė apie grįžtamus laike ryšius (involiuciją) tarp visatoje vykstančių sinergetinių procesų, dėstoma autoriaus formuluojama neomonadologijos sisteminio determinizmo koncepcija
Descartes ir keturi tiksliųjų gamtos mokslų šimtmečiai
This article discusses Descartes’ input into the world picture of exact sciences of the Modern Age. The analytical geometry created by Descartes is considered to be the first successful attempt to develop analytical mathematics as a language of exact sciences. In the article the author looks at Descartes’ rationalism and its impact on the development of modern sciences. The article analyses Descartes’ notions of inertia and the interrelation between matter and space.Straipsnyje apžvelgiamos R. Descartes‘o spręstos matematinės ir gamtamokslinės problemos, aptariami jo gauti rezultatai ir jų poveikis mokslų raidai. Jis pasižymėjo matematikoje, daugelyje fizikos sričių, meteorologijoje, fiziologijoje. R. Descartes sugalvojo algebrinę lygtį atvaizduoti stačiakampėje koordinačių sistemoje. Į geometriją įsiveržus algebrai, jos problemos pradėtos spręsti analitiškai. Tai lėmė tolesnę matematinės analizės raidą. Optikoje R. Descartes‘ui pavyko išaiškinti vaivorykštės prigimtį ir įrodyti, kad optikos prietaisams tinkamiausi ne sferiniai, bet hiperboliniai lęšiai. Siekdamas universaliais principais paaiškinti gamtos reiškinius, R. Descartes įvedė į mokslinę vartoseną gamtos dėsnio sampratą. Jis buvo racionalistinio – deduktyvaus arba aksiominio – fizikos teorijų konstravimo pradininkas. Tokiu metodu gautus dėsnius R. Descartes reikalavo patikrinti eksperimentu
Targeting the search of African swine fever-infected wild boar carcasses : A tool for early detection
Acord transformatiu CRUE-CSICThis study analyses the temporal and spatial distribution of found dead African swine fever (ASF)-positive wild boar carcasses from 2017 to January 2021 in affected European countries: Bulgaria, Estonia, Germany, Hungary, Latvia, Lithuania, Romania, Poland, Serbia and Slovakia. During this period, a total of 21,785 cases were confirmed in 19,071 unique locations. The temporal analysis of aggregated cases per month evidenced that most countries located in southern latitudes showed a higher number of cases between January and April, whereas in northern latitudes there was no clear temporal pattern. The space-time K-function evidenced a space-time clustering in the ASF-positive wild boar carcasses, which was most prominent within distances of 2 km and within 1 week. A Bayesian hierarchical spatial model was calibrated to evaluate the association between the probability of finding ASF-positive wild boar carcasses and landscape factors (i.e. the presence of a path and paved road), land use and wild boar abundance. Results showed the highest likelihood of finding ASF-positive wild boar carcasses in areas of transition between woodland and shrub, green urban areas and mixed forests. The presence of a path and a higher abundance of wild boar also increased slightly the odds of finding an ASF-positive dead wild boar. In summary, this paper aims to provide recommendations to design a search strategy to find ASF-infected wild boar carcasses, which is a crucial activity in the management of the disease, not just for surveillance purposes (i.e. the early detection of an introduction and the regular monitoring to understand the epidemiology and dynamics), but also for control, namely the disposal of infected carcasses as a virus source
Exploring the Preliminary Effects of Resistance Training on Total Brain-Derived Neurotrophic Factor (BDNF) Levels in Elderly Individuals: A Pilot Study
Background: Studies have shown that exercise modulates brain-derived neurotrophic factor (BDNF) levels, and resistance training, in particular, has received increasing attention for its potential to enhance BDNF production. Most studies investigating exercise-induced BDNF changes have focused on free or mature BDNF, while the measurement of total BDNF, encompassing both proBDNF and mature BDNF, may provide a more comprehensive understanding of BDNF regulation. This pilot study aimed to explore the preliminary effects of resistance training on total BDNF levels in elderly individuals participating in a resistance training program.
Methods: A small sample of participants (n=6) was recruited and engaged in a structured resistance training program for 12 weeks, with 6 participants in a control group. Total BDNF levels were measured at baseline and post-intervention using reliable laboratory assessments. Additionally, an isokinetic dynamometer was used to determine muscle strength to explore the effect of the resistance training program on muscle performance.
Results: The findings revealed a significant increase in total BDNF levels following the 12 week resistance training intervention (p<0.05). However, improvements in physical performance measures, knee extension peak torque and isometric maximal voluntary contraction, were not observed.
Conclusion: In conclusion, this pilot study provides preliminary evidence of the positive effects of a 12 week resistance training intervention on total BDNF levels. The measurement of total BDNF levels serves as an important marker in assessing the response to resistance training. Further research with larger sample sizes and longer intervention periods is warranted to further explore the relationship between resistance training and total BDNF levels and to confirm these preliminary findings. Understanding the impact of resistance training on total BDNF levels can have implications for optimizing training programs and potentially improving exercise-related outcomes.
Keywords: muscle strength, exercise, brain-derived neurotrophic factor, neuroplasticity, healthy ageing
Accuracy of a Basketball Indoor Tracking System Based on Standard Bluetooth Low Energy Channels (NBN23®)
The present study aims to identify the accuracy of the NBN23((R)) system, an indoor tracking system based on radio-frequency and standard Bluetooth Low Energy channels. Twelve capture tags were attached to a custom cart with fixed distances of 0.5, 1.0, 1.5, and 1.8 m. The cart was pushed along a predetermined course following the lines of a standard dimensions Basketball court. The course was performed at low speed (10.0 km/h and 20.0 km/h). Root mean square error (RMSE) and percentage of variance accounted for (%VAF) were used as accuracy measures. The obtained data showed acceptable accuracy results for both RMSE and %VAF, despite the expected degree of error in position measurement at higher speeds. The RMSE for all the distances and velocities presented an average absolute error of 0.30 +/- 0.13 cm with 90.61 +/- 8.34 of %VAF, in line with most available systems, and considered acceptable for indoor sports. The processing of data with filter correction seemed to reduce the noise and promote a lower relative error, increasing the %VAF for each measured distance. Research using positional-derived variables in Basketball is still very scarce; thus, this independent test of the NBN23((R)) tracking system provides accuracy details and opens up opportunities to develop new performance indicators that help to optimize training adaptations and performance.This research was funded by Project Project NanoSTIMA: Macro-to-Nano Human Sensing: Towards Integrated Multimodal Health Monitoring and Analytics, NORTE-01-0145-FEDER-000016, Fundo Europeu de Desenvolvimento Regional (FEDER)-NORTE 2020
Unlocking the bacterial SecY translocon
SummaryThe Sec translocon performs protein secretion and membrane protein insertion at the plasma membrane of bacteria and archaea (SecYEG/β), and the endoplasmic reticular membrane of eukaryotes (Sec61). Despite numerous structures of the complex, the mechanism underlying translocation of pre-proteins, driven by the ATPase SecA in bacteria, remains unresolved. Here we present a series of biochemical and computational analyses exploring the consequences of signal sequence binding to SecYEG. The data demonstrate that a signal sequence-induced movement of transmembrane helix 7 unlocks the translocon and that this conformational change is communicated to the cytoplasmic faces of SecY and SecE, involved in SecA binding. Our findings progress the current understanding of the dynamic action of the translocon during the translocation initiation process. The results suggest that the converging effects of the signal sequence and SecA at the cytoplasmic face of SecYEG are decisive for the intercalation and translocation of pre-protein through the SecY channel
Gene-Environment Interaction in a Conditional NMDAR-Knockout Model of Schizophrenia
Interactions between genetic and environmental risk factors take center stage in the
pathology of schizophrenia. We assessed if the stressor of reduced environmental
enrichment applied in adulthood provokes deficits in the positive, negative or cognitive
symptom domains of schizophrenia in a mouse line modeling NMDA-receptor (NMDAR)
hypofunction in forebrain inhibitory interneurons (Grin1∆Ppp1r2
). We find that Grin1∆Ppp1r2
mice, when group-housed in highly enriched cages, appear largely normal across a wide
range of schizophrenia-related behavioral tests. However, they display various short-term
memory deficits when exposed to minimal enrichment. This demonstrates that the
interaction between risk genes causing NMDA-receptor hypofunction and environmental
risk factors may negatively impact cognition later in life
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