Generation of the electrostatic field in the pulsar magnetosphere plasma

The behaviour of a relativistic electron-positron plasma in the pulsar magnetosphere is investigated. The equation of the motion of the magnetospheric plasma is discussed, from which it follows that, if the plasma particle radial velocity ${V_r}>{c/{\sqrt 2}}$ (where c is the speed of light), the centrifugal acceleration changes its sign and the particle braking begins. The stability of the magnetospheric plasma with respect to the radially oriented potential perturbations is discussed and the possibility of the electrostatic field generation in this plasma along the pulsar magnetic field lines is shown.Comment: Plain LaTe

Klassiruumis õppivate õpilaste reaalajas ekspressioonianalüüs näo emotsioonide äratundmise abil

Life is getting more relied on computers. People create new machines and programs to make their lives easier. Devices are involved in a daily routine, so it might be useful if they were capable of understanding human’s verbal or even emotional expressions. Nowadays, computers can learn almost anything and can help to analyze the surrounding world sometimes better than the human sense. The following study can be used while doing a presentation or giving a speech in front of a big audience. It allows the user to be aware of the emotional condition of attending society. During the speech, it is almost impossible to observe every single face of the audience and guess how do they feel; computer vision techniques can do this job for humans. This framework consists of three main parts. In the first part, a pre-trained face detector model collects all the faces seen in the camera and assigns unique IDs. Each face is tracked during the whole video stream using and developing a Simple object tracking algorithm called Centroid Tracker. This tracker relies on a Euclidean distance measurement between the location of object centroid within the current and previous frame of video. The second part of this thesis is Facial Expression Recognition (FER). For this part, Convolutional Neural Network (CNN) is trained over the FER2013 data set. The model is fed a set of face images taken from the previous step, successfully classifies seven different emotional states. The third part stores the data of emotions for each person in such a way that it could be easily understandable for humans. The provided information contains the number of attending people, their facial expressions and overall mood in the audience. By this information, the user gets feedback about his/her speech. This feedback might help people improve presentation skills for the future or even change the presenting style immediately to increase the interest in the audience. In Estonian: Meie aja elu sõltub arvutitest üha enam. Inimesed loovad oma elu lihtsustamiseks uusi masinaid ja programme. Seadmed osalevad meie igapäevases rutiinis, nii et kuigi me oleme nende masinate loojad, vajame neid, et mõista meie suulisi või isegi emotsionaalseid väljendeid. Tänapäeval saavad arvutid õppida peaaegu kõike ja aitavad meil ümbritsevat maailma mõnikord isegi paremini analüüsida, kui teeme seda inimlike meelte järgi. Järgnevat uuringut saab kasutada ettekande tegemisel või suure publiku ees kõne pidamisel. See võimaldab kasutajal olla teadlik ühiskonnas käimise emotsionaalsest olukorrast. Kõne ajal on peaaegu võimatu jälgida iga nägu publikus ja arvata, kuidas nad end tunnevad; arvuti nägemise tehnikad teevad selle töö meie eest. See raamistik koosneb kolmest põhiosast. Esimeses osas kogub eelkoolituse saanud näotuvastuse mudel kõik kaameras nähtud näod ja määrab ainulaadsed ID-d. Iga nägu jälgitakse kogu videovoo jooksul, kasutades ja arendades lihtsat objektide jälgimise algoritmi nimega Centroid Tracker. See jälgija tugineb Eukleidese vahekauguse mõõtmisele objekti keskpunkti asukoha vahel video praeguses ja eelmises kaadris.Lõputöö teine osa on näoilmetuvastus (FER). Selle jaoks koolitatakse FER2013 andmekogu kaudu konvolutsioonilist närvivõrku (CNN). Mudelile sisestatakse eelmisest etapist võetud näopiltide komplekt, see klassifitseerib edukalt seitse erinevat emotsionaalset olekut. Kolmas osa salvestab emotsioonide andmed iga inimese kohta viisil, mis oleks inimestele kergesti arusaadav. Esitatud teave sisaldab osalevate inimeste arvu, nende näoilmeid ja üldist meeleolu publikus. Selle teabe abil saab kasutaja tagasisidet oma kõne kohta. See tagasiside võib aidata edaspidiseks esinemisoskust parendada või isegi esitusstiili kohe muuta, et suurendada publiku huvi

Defining the mechanisms of neutrophil exocytosis using proteomic techniques.

Exocytosis of intracellular granules is critical for conversion of inactive, circulating neutrophils to fully activated cells. The p38 MAPK pathway plays a central role in neutrophil exocytosis, although its mechanism of action is unknown. We used several proteomic approaches to identify granule proteins and find targets of the p38 MAPK and its downstream kinase, MK2, on granules. Our analysis identified 286 proteins on neutrophil granules, four of which were known MK2 substrates. Known p38 substrates were not detected. However, MRP-14 was identified as a novel p38 MAPK substrate. MRP-14 was phosphorylated by p38 MAPK in neutrophils upon cell stimulation and translocated to plasma membranes and gelatinase granules, as well as to Triton X-100-insoluble structures at the base of lamellipodia. Phosphorylation of the MRP-14 by p38 MAPK increased binding to actin in vitro. These results suggest that MRP-14 is a potential mediator of p38 MAPK-dependent exocytosis in human neutrophils

ИНТЕНСИВНАЯ ТЕХНОЛОГИЯ ВЫРАЩИВАНИЯ КЛУБНИКИ В ЗАКРЫТОМ ГРУНТЕ

The intensive technology of growing strawberries under cover, the production of maximum yield in the greenhouses, the structure of strawberry beds, the preparation, composting and sterilization of the substrate, raising the seedlings of strawberry, comparative economic evaluation they are KEYWORDS reviewed in the article.The intensive technology of growing strawberries under cover, the production of maximum yield in the greenhouses, the structure of strawberry beds, the preparation, composting and sterilization of the substrate, raising the seedlings of strawberry, comparative economic evaluation they are KEYWORDS reviewed in the article

Transverse quasilinear relaxation in inhomogeneous magnetic field

Transverse quasilinear relaxation of the cyclotron-Cherenkov instability in the inhomogeneous magnetic field of pulsar magnetospheres is considered. We find quasilinear states in which the kinetic cyclotron-Cherenkov instability of a beam propagating through strongly magnetized pair plasma is saturated by the force arising in the inhomogeneous field due to the conservation of the adiabatic invariant. The resulting wave intensities generally have nonpower law frequency dependence, but in a broad frequency range can be well approximated by the power law with the spectral index -2. The emergent spectra and fluxes are consistent with the one observed from pulsars.Comment: 14 Pages, 4 Figure

Nature of eclipsing pulsars

We present a model for pulsar radio eclipses in some binary systems, and test this model for PSRs B1957+20 and J2051-0827. We suggest that in these binaries the companion stars are degenerate dwarfs with strong surface magnetic fields. The magnetospheres of these stars are permanently infused by the relativistic particles of the pulsar wind. We argue that the radio waves emitted by the pulsar split into the eigenmodes of the electron-positron plasma as they enter the companion's magnetosphere and are then strongly damped due to cyclotron resonance with the ambient plasma particles. Our model explains in a natural way the anomalous duration and behavior of radio eclipses observed in such systems. In particular, it provides stable, continuous, and frequency-dependent eclipses, in agreement with the observations. We predict a significant variation of linear polarization both at eclipse ingress and egress. In this paper we also suggest several possible mechanisms of generation of the optical and $X$-ray emission observed from these binary systems.Comment: 12 pages, 5 figures, submitted to Ap

Stream instabilities in relativistically hot plasma

The instabilities of relativistic ion beams in a relativistically hot electron background are derived for general propagation angles. It is shown that the Weibel instability in the direction perpendicular to the streaming direction is the fastest growing mode, and probably the first to appear, consistent with the aligned filaments that are seen in PIC simulations. Oblique, quasiperpendicular modes grow almost as fast, as the growth rate varies only moderately with angle, and they may distort or corrugate the filaments after the perpendicular mode saturates.Comment: 10 pages, 6 figure

A Dual-Tracer Method for Differentiating Transendothelial Transport from Paracellular Leakage in Vivo and in Vitro

Inflammation-induced impaired function of vascular endothelium may cause leakage of plasma proteins that can lead to edema. Proteins may leave the vascular lumen through two main paracellular and transcellular pathways. As the first involves endothelial cell (EC) junction proteins and the second caveolae formation, these two pathways are interconnected. Therefore, it is difficult to differentiate the prevailing role of one or the other pathway during pathology that causes inflammation. Here we present a newly developed dual-tracer probing method that allows differentiation of transcellular from paracellular transport during pathology. This fluorescence-based method can be used in vitro to test changes in EC layer permeability and in vivo in various animal vascular preparations. The method is based on comparison of low molecular weight molecule (LMWM) transport to that of high molecular weight molecule (HMWM) transport through the EC layer or the vascular wall during physiological and pathological conditions. Since the LMWM will leak through mainly the paracellular and HMWM will move through paracellular (when gaps between the ECs are wide enough) and transcellular pathways, the difference in transport rate (during normal conditions and pathology) of these molecules will indicate the prevailing transport pathway involved in overall protein crossing of vascular wall. Thus, the novel approach of assessing the transport kinetics of different size tracers in vivo by intravital microscopy can clarify questions related to identification of target pathways for drug delivery during various pathologies associated with elevated microvascular permeability