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2022 ◽  
Vol 12 (5) ◽  
pp. 964-970
Tao Liu ◽  
Xiang Wen ◽  
Qi-Jun Zhao ◽  
Ying Bai ◽  
Qing-Gang Tian

The paclitaxel is a common-used chemotherapy drug and its combination with nano albumin reduces drug side effect. However, whether nab-paclitaxel affects drug resistance of breast cancer remains unclear. This study intends to discuss the mechanism of drug resistance induced by nab-paclitaxel. The drug resistance of MCF-7/nab-paclitaxel in MCF-7 cell and cell proliferation was detected by MTT along with analysis of ABCB1 expression, cell cycle, and apoptosis. There was stronger drug resistance of nab-paclitaxel in the MCF-7/nab-paclitaxel cell group through be adopted with different concentration of nab-paclitaxel at the 0th hour, 24th hour and 48th hour. There was remarkable abnormal expression of the ABCB1 in the MCF-7/nab-paclitaxel cell group. The si-ABCB1 could release the quantity of the MCF-7/nab-paclitaxel cell blocked at S period. And the si-ABCB1 could reduce the expression of cyclin D1 and CDK2 in the MCF-7/nab-paclitaxel cell notably. But the expression level of p21 was increased when there was high concentration of si-ABCB1. The si-ABCB1 could increase the quantity of the MCF-7/nab-paclitaxel cell at the later period of cell apoptosis notably. The rat’s tumor growth was delayed obviously at the MCF-7/nabpaclitaxel cell group treated by si-ABCB1. But the inhibiting effect of the MCF-7/nab-paclitaxel cell on tumor growth was less. There was stronger drug resistance of cell for the nano albumin combined with paclitaxel. The function of cell proliferation in breast cancer was restrained by the nano albumin combined with paclitaxel mainly through inducing the expression of ABCB1, adjusting the growth of cell cycle and the expression of P21/BCL-2 protein.

2022 ◽  
Vol 45 (1) ◽  
pp. 57-62
L.J . OGALLO ◽  
R. E. OKOOLA ◽  

investigated using monthly zo.ta l wind com ponents from Nairob i (Kenya ) within the period1966-1987. RelatiHn.;;hips between the stra tospher ic eas terl y and westerly wino phases and t he seasona l ra infallanomalics were also iO\t,"..')t igatN.Res ults Irom spec tra l a nalysis indicated tho d ominance (If a 28 mon th s' period in the IllOal w ind comnoncn.The \'Crtical ra te of propagar ioa of both westerly and easterly wind phases was about - · 1.2 kmmonth.Results from statist ical analysis indicated signitica nr (at 5 '~~ level) association between rainfall anomalyclass (above normal. normal. a mi below normal) and east erly and westerl y wind phas...es.

2021 ◽  
Vol 11 (1) ◽  
Mitesh Patel ◽  
Maria H. Nilsson ◽  
Stig Rehncrona ◽  
Fredrik Tjernström ◽  
Måns Magnusson ◽  

AbstractParkinson’s disease (PD) is characterized by rigidity, akinesia, postural instability and tremor. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces tremor but the effects on postural instability are inconsistent. Another component of postural control is the postural strategy, traditionally referred to as the ankle or hip strategy, which is determined by the coupling between the joint motions of the body. We aimed to determine whether DBS STN and vision (eyes open vs. eyes closed) affect the postural strategy in PD in quiet stance or during balance perturbations. Linear motion was recorded from the knee, hip, shoulder and head in 10 patients with idiopathic PD with DBS STN (after withdrawal of other anti-PD medication), 25 younger adult controls and 17 older adult controls. Correlation analyses were performed on anterior–posterior linear motion data to determine the coupling between the four positions measured. All participants were asked to stand for a 30 s period of quiet stance and a 200 s period of calf vibration. The 200 s vibration period was subdivided into four 50 s periods to study adaptation between the first vibration period (30–80 s) and the last vibration period (180–230 s). Movement was recorded in patients with PD with DBS ON and DBS OFF, and all participants were investigated with eyes closed and eyes open. DBS settings were randomized and double-blindly programmed. Patients with PD had greater coupling of the body compared to old and young controls during balance perturbations (p ≤ 0.046). Controls adopted a strategy with greater flexibility, particularly using the knee as a point of pivot, whereas patients with PD adopted an ankle strategy, i.e., they used the ankle as the point of pivot. There was higher flexibility in patients with PD with DBS ON and eyes open compared to DBS OFF and eyes closed (p ≤ 0.011). During balance perturbations, controls quickly adopted a new strategy that they retained throughout the test, but patients with PD were slower to adapt. Patients with PD further increased the coupling between segmental movement during balance perturbations with DBS ON but retained a high level of coupling with DBS OFF throughout balance perturbations. The ankle strategy during balance perturbations in patients with PD was most evident with DBS OFF and eyes closed. The increased coupling with balance perturbations implies a mechanism to reduce complexity at a cost of exerting more energy. Strategic alterations of posture were altered by DBS in patients with PD and were delayed. Our findings therefore show that DBS does not fully compensate for disease-related effects on posture.

C H Agar ◽  
P Weltevrede ◽  
L Bondonneau ◽  
J-M Grießmeier ◽  
J W T Hessels ◽  

Abstract We present radio observations of the most slowly rotating known radio pulsar PSR J0250+5854. With a 23.5 s period, it is close, or even beyond, the P-$\dot{P}$ diagram region thought to be occupied by active pulsars. The simultaneous observations with FAST, the Chilbolton and Effelsberg LOFAR international stations, and NenuFAR represent a five-fold increase in the spectral coverage of this object, with the detections at 1250 MHz (FAST) and 57 MHz (NenuFAR) being the highest- and lowest-frequency published respectively to date. We measure a flux density of 4 ± 2 μJy at 1250 MHz and an exceptionally steep spectral index of $-3.5^{+0.2}_{-1.5}$, with a turnover below ∼95 MHz. In conjunction with observations of this pulsar with the GBT and the LOFAR Core, we show that the intrinsic profile width increases drastically towards higher frequencies, contrary to the predictions of conventional radius-to-frequency mapping. We examine polarimetric data from FAST and the LOFAR Core and conclude that its polar cap radio emission is produced at an absolute height of several hundreds of kilometres around 1.5 GHz, similar to other rotation-powered pulsars across the population. Its beam is significantly underfilled at lower frequencies, or it narrows because of the disappearance of conal outriders. Finally, the results for PSR J0250+5854 and other slowly spinning rotation-powered pulsars are contrasted with the radio-detected magnetars. We conclude that magnetars have intrinsically wider radio beams than the slow rotation-powered pulsars, and that consequently the latter’s lower beaming fraction is what makes objects such as PSR J0250+5854 so scarce.

2021 ◽  
Xiaolong Ma ◽  
Hrvoje Tkalčić

The existing Earth reference models have provided an excellent one-dimensional representation of Earth’s properties as a function of its radius and explained many seismic observations in a broad frequency band. However, some discrepancies still exist among these models near the first-order discontinuities (e.g., the core-mantle and the inner-core boundaries) due to different datasets and approaches. As a new paradigm in global seismology, the analysis of coda-correlation wavefield is fundamentally different from interpreting direct observations of seismic phases or free oscillations of the Earth. The correlation features exist in global correlograms due to the similarity of body waves reverberating through the Earth’s interior. As such, there is a great potential to utilize the information stored in the coda-correlation wavefield in constraining the Earth’s internal structure. Here, we deploy the global earthquake-coda correlation wavefield as an independent data source in the 15-50 s period interval to increase the Earth's radial structure constraints. We assemble a dataset of multiple pronounced correlation features and fit both their travel times and waveforms by computing synthetic correlograms through a series of candidate models. Misfit measurements for correlation features are then computed to search for the best-fitting model. The model that provides an optimal representation of the correlation features in the coda-correlation wavefield is CCREM. It displays differences in radial seismic velocities, especially near the first-order discontinuities, relative to previously proposed Earth-reference models. This is the first application of the earthquake-coda correlation wavefield in constraining the whole Earth's radial velocity structure.

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0256849
Ellen M. Kok ◽  
Bettina Sorger ◽  
Koos van Geel ◽  
Andreas Gegenfurtner ◽  
Jeroen J. G. van Merriënboer ◽  

Radiologists can visually detect abnormalities on radiographs within 2s, a process that resembles holistic visual processing of faces. Interestingly, there is empirical evidence using functional magnetic resonance imaging (fMRI) for the involvement of the right fusiform face area (FFA) in visual-expertise tasks such as radiological image interpretation. The speed by which stimuli (e.g., faces, abnormalities) are recognized is an important characteristic of holistic processing. However, evidence for the involvement of the right FFA in holistic processing in radiology comes mostly from short or artificial tasks in which the quick, ‘holistic’ mode of diagnostic processing is not contrasted with the slower ‘search-to-find’ mode. In our fMRI study, we hypothesized that the right FFA responds selectively to the ‘holistic’ mode of diagnostic processing and less so to the ‘search-to-find’ mode. Eleven laypeople and 17 radiologists in training diagnosed 66 radiographs in 2s each (holistic mode) and subsequently checked their diagnosis in an extended (10-s) period (search-to-find mode). During data analysis, we first identified individual regions of interest (ROIs) for the right FFA using a localizer task. Then we employed ROI-based ANOVAs and obtained tentative support for the hypothesis that the right FFA shows more activation for radiologists in training versus laypeople, in particular in the holistic mode (i.e., during 2s trials), and less so in the search-to-find mode (i.e., during 10-s trials). No significant correlation was found between diagnostic performance (diagnostic accuracy) and brain-activation level within the right FFA for both, short-presentation and long-presentation diagnostic trials. Our results provide tentative evidence from a diagnostic-reasoning task that the FFA supports the holistic processing of visual stimuli in participants’ expertise domain.

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2553
Pinakin Gunvant Davey ◽  
Richard B. Rosen ◽  
Dennis L. Gierhart

The study was designed to: (1) Analyze and create protocols of obtaining measurements using the Macular Pigment Reflectometry (MPR). (2) To assess the agreement of MPOD measurements obtained using the heterochromatic flicker photometry (MPS II) and MPR. (3) To obtain the lutein and zeaxanthin optical density obtained using the MPR in the central one-degree of the macula. The measurements were performed using the MPR and heterochromatic flicker photometry. The MPR measurements were performed twice without pupillary dilation and twice following pupillary dilation. The MPR measurements were performed for a 40-s period and the spectrometer signal was parsed at different time points: 10–20, 10–30, 10–40, 20–30, 20–40, and 30–40 s. The MPR analyzes the high-resolution spectrometer signal and calculates MPOD, lutein optical density and zeaxanthin optical density automatically. The MPR-MPOD data was compared with MPPS II-MPOD results. The MPR-MPOD values are highly correlated and in good agreement with the MPS II-MPOD. Of the various parsing of the data, the data 10–30 interval was the best at obtaining the MPOD, lutein, and zeaxanthin values (8–12% coefficient of repeatability). The lutein to zeaxanthin ratio in the central one-degree of the macula was 1:2.40. Dilation was not needed to obtain the MPOD values but provided better repeatability of lutein and zeaxanthin optical density. MPR generates MPOD measurements that is in good agreement with MPS II. The device can produce lutein and zeaxanthin optical density which is not available from other clinical devices.

2021 ◽  
Vol 39 (4) ◽  
pp. 657-685
Yiyang Luo ◽  
Leonid Chernogor ◽  
Kostiantyn Garmash ◽  
Qiang Guo ◽  
Victor Rozumenko ◽  

Abstract. The concept that geospace storms are comprised of synergistically coupled magnetic storms, ionospheric storms, atmospheric storms, and storms in the electric field originating in the magnetosphere, the ionosphere, and the atmosphere (i.e., electrical storms) was validated a few decades ago. Geospace storm studies require the employment of multiple-method approaches to the Sun–interplanetary medium–magnetosphere–ionosphere–atmosphere–Earth system. This study provides general analysis of the 30 August–2 September 2019 geospace storm, the analysis of disturbances in the geomagnetic field and in the ionosphere, as well as the influence of the ionospheric storm on the characteristics of high frequency (HF) radio waves over the People's Republic of China. The main results of the study are as follows. The energy and power of the geospace storm have been estimated to be 1.5×1015 J and 1.5×1010 W, and thus, this storm is weak. The energy and power of the magnetic storm have been estimated to be 1.5×1015 J and 9×109 W, i.e., this storm is moderate, and a characteristic feature of this storm is the duration of the main phase of up to 2 d. The recovery phase also was lengthy and was no less than 2 d. On 31 August and 1 September 2019, the variations in the H and D components attained 60–70 nT, while the Z-component variations did not exceed 20 nT. On 31 August and 1 September 2019, the level of fluctuations in the geomagnetic field in the 100–1000 s period range increased from 0.2–0.3 to 2–4 nT, while the energy of the oscillations showed a maximum in the 300–400 to 700–900 s period range. During the geospace storm, a moderately to strongly negative ionospheric storm manifested itself by the reduction in the ionospheric F-region electron density by a factor of 1.4 to 2.4 times on 31 August and 1 September 2019, compared to the its values on the reference day. Appreciable disturbances were also observed to occur in the ionospheric E region and possibly in the Es layer. In the course of the ionospheric storm, the altitude of reflection of radio waves could sharply increase from ∼150 to ∼300–310 km. The atmospheric gravity waves generated within the geospace storm modulated the ionospheric electron density; for the ∼30 min period oscillation, the amplitude of the electron density disturbances could attain ∼40 %, while it did not exceed 6 % for the ∼15 min period. At the same time, the height of reflection of the radio waves varied quasi-periodically with a 20–30 km amplitude. The results obtained have made a contribution to the understanding of the geospace storm physics, to developing theoretical and empirical models of geospace storms, to the acquisition of detailed understanding of the adverse effects that geospace storms have on radio wave propagation, and to applying that knowledge to effective forecasting of these adverse influences.

2021 ◽  
Vol 11 (1) ◽  
Fabrizio Magrini ◽  
Lapo Boschi ◽  
Lucia Gualtieri ◽  
Vedran Lekić ◽  
Fabio Cammarano

AbstractMapping variations in the attenuation of seismic energy is important for understanding dissipative mechanisms in the lithosphere, and for modeling ground shaking associated with earthquakes. We cross-correlate ambient seismic signal recorded across the EarthScope Transportable Array in the 3–15 s period range. We apply to the resulting cross correlations a new method to estimate lateral variations in Rayleigh-wave attenuation, as a function of period, beneath North America. Between 3 and 6 s, our maps are dominated by a strong eastward decrease in attenuation. This pattern vanishes at longer periods, confirming early observations based on regional earthquakes. Attenuation maps and phase-velocity maps are anti-correlated at periods between 3 and 6 s, but the anti-correlation is also largely lost at longer periods. This corresponds to the attenuation coefficient decreasing with period more rapidly in the west than in the east, while the change in phase velocity with period is more uniform across the continent. Our results point to a transition in the properties of upper-crustal materials with depth, probably related to the closure of fluid-filled cracks and pores, and imply that measures of attenuation from seismic noise carry significant information on crustal rheology.

2021 ◽  
pp. 5-8
Tetiana HANUSHCHAK ◽  
Vladyslav KARIMOV

Introduction. An important step in the development of our country's economy and world activity in general is the digitalization of production and economic processes. Historically, we live in a digitalization`s period. It is necessary to take into account the company`s scope, including the financial capabilities. The purpose of the paper is to study the digitalization`s development in the enterprise and its impact on the economy. Results. In the article presents the main software products for processing financial and accounting information in an enterprise. The computers structure use by Ukraine`s industry is given. An example of digitalization management of leading foreign companies is given. The author's vision of solving the problem of the digitalization`s development at the enterprise is presented. It is global and inclusive. Enterprises working on the introduction and development of digitalization of the following software products:ITSM 365, IntraService, vsDesk, OMNITRACKER, OTRS, Alloy Navigator, Alloy Navigator, ITMan, Pyrus Service Desk, 1С:ITIL. Foreign and large Ukrainian companies use: SAP, Project Expert, EViews. The highest mobile average of employees using computers, in% of the total number of employees in 2019 compared to 2018 in the transport`s scope, households, postal and courier activities increased оn 33 267 people or 6,5 %. Conclusions. Summarizing the results of the digitalization's study of the enterprise, we can following conclusions, namely: today's transformation processes are a driving force in the development of innovation and strategic planning. Of course, enterprise`s situational management with the use of the latest technologies is the development not only an individual enterprise, but also the whole of the country`s economy. The important factor in economic`s development is digitalization, which has penetrated into all spheres of the public life. On the digitalization`s development in our country are influencing hostilities and pandemic. These factors lead to a reduction in expenditures from the state budget. The government and local authorities need to seek help from developed countries, grants.

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