Jānis Cīmurs

Dr. Jānis Cīmurs

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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 February 2015 in Soft Matter
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Journal Article
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ABArtis Brasovs
Artis Brasovs
JCJānis Cīmurs
Jānis Cīmurs
KĒKaspars Ērglis
Kaspars Ērglis
AZAndris Zeltins
Andris Zeltins
Jean-François BerretJean-François Berret
Jean-François Berret
ACAndrejs Cēbers
Andrejs Cēbers
The protocol of microrheological measurements consists of recording the dynamics of the orientation of the rod when the magnetic field is applied at an angle to the rod and observing its relaxation after the field is switched off.

2 August 2019 in Biosensors
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Journal Article
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URUldis Rubins
Uldis Rubins
ZMZbignevs Marcinkevics
Zbignevs Marcinkevics
JCJānis Cīmurs
Jānis Cīmurs
ISInga Saknite
Inga Saknite
EKEdgars Kviesis-Kipge
Edgars Kviesis-Kipge
AGAndris Grabovskis
Andris Grabovskis
The present study introduces a recently developed compact hybrid device for real-time monitoring of skin oxygen saturation and temperature distribution. The prototype involves a snapshot hyperspectral camera, multi-wavelength illuminator, thermal camera, and built-in computer with custom-developed software. To validate this device in-vivo we performed upper arm vascular occlusion on eight healthy volunteers. Palm skin oxygen saturation maps were analyzed in real-time using k-means segmentation algorithm and two-layer optical diffuse model. The prototype system demonstrated a satisfying performance of skin hyperspectral measurements in the spectral range of 507–625 nm. The results confirmed the reliability of the proposed system for in-vivo assessment of skin hemoglobin saturation with oxygen and microcirculation.

3 October 2022 in Physical Review B
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DZDavis Zavickis
Davis Zavickis
KKKristians Kacars
Kristians Kacars
JCJānis Cīmurs
Jānis Cīmurs
AGAndris Gulans
Andris Gulans
We present an implementation of the adaptively compressed exchange (ACE) operator in the linearized-augmented plane waves formalism. ACE is a low-rank representation of the Fock exchange that avoids any loss of precision for the total energy. Our study shows that this property remains in the all-electron case, as we apply this method in nonrelativistic total-energy calculations with a hybrid exchange-correlation functional PBE0. The obtained data for light atoms and molecules are within a few μHa of the precise multiresolution-analysis calculations. Aside from ACE, another key ingredient to achieve such a high precision with Fock exchange was the use of high-energy local orbitals. Finally, we use this implementation to calculate PBE0 gaps in solids and compare the results to other all-electron results.

1 January 2022 in Journal of Magnetism and Magnetic Materials
Verified
Journal Article
Open access
JUJānis Užulis
Jānis Užulis
JCJānis Cīmurs
Jānis Cīmurs

17 May 2018
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Conference Paper
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URUldis Rubins
Uldis Rubins
AGAndris Grabovskis
Andris Grabovskis
JCJānis Cīmurs
Jānis Cīmurs
ZMZbignevs Marcinkevics
Zbignevs Marcinkevics
ACAnastasija Caica
Anastasija Caica
Skin capillary blood oxygen saturation is a clinically important diagnostic parameter, which provides valuable information for timely treatment of pathological conditions e.g. sepsis, hypoxemia or decompression illness. Hyperspectral imaging is non-invasive optical techniques with high clinical potential, however its use for skin blood oxygen saturation detection is still challenging, therefore in the present study, a method for in-vivo manipulation of skin oxygen saturation was developed, and reliability of the method evaluated by means of hyperspectral imaging in detection of oxygen saturation. In order to produce alterations of skin capillary blood parameters and oxygen saturation, the proximal phalanx of the right middle finger was occluded with a pneumatic cuff for 25 minutes. During the last minute of occlusion, the hyperspectral cubes (HIS) of both occluded and intact finger were captured, and capillary blood sample was collected for analysis with portable whole blood analyzer (REF). The group mean values for SaO2 in intact finger skin was HIS: 89.46%±8.79% versus REF: 95.13±1.46 % and in occluded finger HSI: 25.85% ±14.00%, versus REF: 22.73±9.09 % displaying a small difference between two independent techniques, which indicate the reliability of finger occlusion model.

1 June 2018
Verified
Conference Paper
Closed access
KEKaspars Erglis
Kaspars Erglis
JCJānis Cīmurs
Jānis Cīmurs
GKGuntars Kitenbergs
Guntars Kitenbergs
Distribution of magnetic field around different magnetic objects is important for various applications of magnetic materials. Field distribution can be measured with a 3-axis Hall probe sensor, which is moved around the sample. There are excellent systems available in market for this purpose for example, magnetic field mapper MMS-1A-RS from SENIS AG. However, these systems are quite expensive, starting from 25 000 ϵ. Here we demonstrate how a simple automated magnetic field mapper can be made from common parts found in laboratories, test it to verify accuracy, compare results with numerical simulations and discuss the benefits of this low-cost alternative.