Lower Right Research Articles

Reviewing Space-Borne GNSS-Reflectometry for Detecting Freeze/Thaw Conditions of Near-Surface Soils

GNSS-Reflectometry, a technique that harnesses the power of microwave remote sensing, is poised to revolutionize our ability to detect and monitor near-surface soil freeze/thaw processes. This technique’s theoretical underpinnings are deeply rooted in the comprehensive explanation of the Zhang–Zhao dielectric constant model, which provides crucial insights into the behavior of frozen and thawed soils. The model elucidates how the dielectric properties of soil change as it transitions between frozen and thawed states, offering a scientific basis for understanding reflectivity variations. Furthermore, the theoretical framework includes a set of formulas that are instrumental in calculating reflectivity at Lower Right (LR) polarization and in deriving Dual-Polarization Differential Observables (DDMs). These calculations are pivotal for interpreting the signals captured by GNSS-R sensors, allowing for the detection of subtle changes in the soil’s surface conditions. The evolution of GNSS-R as a tool for detecting freeze/thaw phenomena has been substantiated through qualitative analyses involving multiple satellite missions, such as SMAP-R, TDS-1, and CYGNSS. These analyses have provided empirical evidence of the technique’s effectiveness, illustrating its capacity to capture the dynamics of soil freezing and thawing processes. In addition to these qualitative assessments, the application of a discriminant retrieval algorithm using data from CYGNSS and F3E GNOS-R has further solidified the technique’s potential. This algorithm contributes to refining the accuracy of freeze/thaw detection by distinguishing between frozen and thawed soil states with greater precision. The deployment of space-borne GNSS-R for monitoring near-surface freeze/thaw cycles has yielded commendable results, exhibiting robust consistency and delivering relatively precise retrieval outcomes. These achievements stand as testaments to the technique’s viability and its growing significance in the field of remote sensing. However, it is imperative to recognize and actively address certain limitations that have been highlighted in this review. These limitations serve as critical focal points for future research endeavors, directing the efforts toward enhancing the technique’s overall performance and applicability. Addressing these challenges will be essential for leveraging the full potential of GNSS-R to advance our understanding and management of near-surface soil freeze/thaw processes.

Enhancing an image’s compression while keeping quality standards utilizing new mathematical technology

The rapid development of technology led to the need to keep pace with it, especially in the field of image processing, because of its importance in the need to get better results. In this paper, new discrete Chebyshev wavelet transforms (DChWT) derived from Chebyshev polynomials (ChP) were proposed and characterized. In terms of orthogonality and approximation (convergence) in the field of mathematics, (ChP) were qualified to transform into discrete wavelets called (DChWT), depending on the mother function with operators (s, r), and were used in image processing to analyze them in the low filter and the high filter so that the image is analyzed into coefficients. Proximity and detail coefficients, which lead to dividing the image into four parts, low left (LL), in which the proximity coefficients are concentrated while the rest of the parts are centered on the detail coefficients, which are high left (HL), low right (LR), and high right (HR), and image compression through the new filter, which has proven its efficiency at level (8) in our results. The results of the proposed wavelets in this work were reached in calculating quality standards in the image obtained after the compression process after comparing them with the results obtained using the standard wavelet used in HaarSymlet 2, Conflict 2, and Daubecheis 2. The most important of these standards is a mean square error (MSE), peak signal-to-noise ratio (PSNR), bit per pixel (BPP), compression ratio (CR), and table one. In this paper, the efficiency of the proposed new wavelets is explained after adding it to MATLAB and according to a specific program to drop in with the basic wavelets to take on their role in important tasks in the image processing area, like artificial intelligence

Analysis of characteristics about far-side occupant’s chest injury during oblique side impact

The chest is one of the most frequently injured body parts during a side impact. In this study, the effects of impact angle, impact speed, and D-ring position on the occupant’s chest injury in the far-side crash were analyzed. First, a model with a sled and a Test Human Occupant Restraint (THOR) dummy was established. Second, the acceleration curves with peaks of 6.6 and 9.0 g were applied to the sled. Then 12 sets of simulations with different impact angles and D-ring positions were conducted to evaluate the occupant’s chest responses. Results indicate that the peak chest deflection at Lower Left (LL) decreased by 11.6% on average, and that at Lower Right (LR) increased by 11.7% on average when the D-ring position moved backward. Meanwhile, with the D-ring position moving upward, the peak chest deflection at LL grew by 24.8% on average, while it decreased by 14.7% at LR.

English MODULATION OF MELATONIN SECRETION WITH TRANSCUTANEOUS AURICULAR NERVE STIMULATION: A CASE STUDY

The main study objective was to test the hypothesis that selective electrical transcutaneous auricular nerve stimulation (tANS) under forenoon daylight conditions induces melatonin secretion in a 64-year-old male patient with angina pectoris, hypercholesterolomy and coronary artery disease, assuming that it has beneficial effects on accompanied insomnia (Regensburg Insomnia Scale (RIS) = 22 points, the total score ranges from 0 to 40). Silicone stimulation plugs, with two platinum stimulating cathodes each, were inserted into the left and right external ears. Afterwards, one-second-long pulse trains of cathodic, biphasic and current regulated stimulating pulses at stimulating charge density Cd of 50.88 µC/cm2 and frequency of 25 Hz, were delivered for 30 min to selected sites at the upper and lower part of the left and right Cymba Conchae (CC), respectively. The common anode was attached to the neck. The time gap between the pulse trains was measured by the patient using a tactile sensor and was about 250 ms. The results showed that selective tANS under forenoon daylight conditions increased melatonin saliva levels in all the trials accomplished in a patient. Precisely, the lowest increase was obtained in trials with lower right (LR) CC, while the highest increase was obtained in upper-right (UR) CC trials.

In-Vivo Dosimetry for Small Animal Irradiation: A Preliminary Study

This study assessed applications for in-vivo dosimetry using a 3D printer-based, self-manufactured mouse immobilization device in a small field. The mouse immobilization device was created using a 3D printer (Makerbot Replicator, MakerBot Industries, Brooklyn, NY, USA) and consisted of the support flat, fixing units, sensor areas, and a build-up cap. Radio-photoluminescence glass dosimeters (RPLGD, GD-302M) were inserted at the upper left (UL), upper right (UR), lower left (LL), and lower right (LR) of the device at the center of the target. EBT3 film was inserted into the device at the top of the mouse’s head. Irradiation planning was performed using the ECLIPSE system after a CT simulation of mice with an immobilization device. The mice were irradiated 5 times at a dose 180 cGy with 6 MV X-rays. The dose measurements from the RPLGDs and films were compared with the doses calculated in the Eclipse system. The percentage differences between the Radiation Treatment Planning (RTP) System and RPLGD measurements were 5.56 ± 3.90%, 6.52 ± 5.32%, 10.0 ± 8.97%, and 15.9 ± 17.5% at the UL, UR, LL, and LR positions, respectively. The gamma passing rate of all film measurements exceeded 90% in the 2%/2 mm range. The error values of the 3rd measurements were outliers due to the set up. With the exception of the 3rd measurements, the percentage difference decreased to 4–7%. In this study, we evaluated the applicability of a mouse immobilization device in a small field. We performed in-vivo dosimetry using RPLGD and EBT3 film; this approach may be helpful for using radiation to accurately analyze results in animal studies.

Synthesis, Crystal Study, and Anti-Proliferative Activity of Some 2-Benzimidazolylthioacetophenones towards Triple-Negative Breast Cancer MDA-MB-468 Cells as Apoptosis-Inducing Agents.

On account of its poor prognosis and deficiency of therapeutic stratifications, triple negative breast cancer continues to form the causative platform of an incommensurate number of breast cancer deaths. Aiming at the development of potent anticancer agents as a continuum of our previous efforts, a novel series of 2-((benzimidazol-2-yl)thio)-1-arylethan-1-ones 5a–w was synthesized and evaluated for its anti-proliferative activity towards triple negative breast cancer (TNBC) MDA-MB-468 cells. Compound 5k was the most active analog against MDA-MB-468 (IC50 = 19.90 ± 1.37 µM), with 2.1-fold increased activity compared to 5-fluorouracil (IC50 = 41.26 ± 3.77 µM). Compound 5k was able to induce apoptosis in MDA-MB-468, as evidenced by the marked boosting in the percentage of florecsein isothiocyanate annexin V (Annexin V–FITC)-positive apoptotic cells (upper right (UR) + lower right (LR)) by 2.8-fold in comparison to control accompanied by significant increase in the proportion of cells at pre-G1 (the first gap phase) by 8.13-fold in the cell-cycle analysis. Moreover, a quantitative structure activity relationship (QSAR) model was established to investigate the structural requirements orchestrating the anti-proliferative activity. Finally, we established a theoretical kinetic study.

Changes in Positive End-Expiratory Pressure Alter the Distribution of Ventilation within the Lung Immediately after Birth in Newborn Rabbits

Current recommendations suggest the use of positive end-expiratory pressures (PEEP) to assist very preterm infants to develop a functional residual capacity (FRC) and establish gas exchange at birth. However, maintaining a consistent PEEP is difficult and so the lungs are exposed to changing distending pressures after birth, which can affect respiratory function. Our aim was to determine how changing PEEP levels alters the distribution of ventilation within the lung. Preterm rabbit pups (28 days gestation) were delivered and mechanically ventilated with one of three strategies, whereby PEEP was changed in sequence; 0-5-10-5-0 cmH2O, 5-10-0-5-0 cmH2O or 10-5-0-10-0 cmH2O. Phase contrast X-ray imaging was used to analyse the distribution of ventilation in the upper left (UL), upper right (UR), lower left (LL) and lower right (LR) quadrants of the lung. Initiating ventilation with 10PEEP resulted in a uniform increase in FRC throughout the lung whereas initiating ventilation with 5PEEP or 0PEEP preferentially aerated the UR than both lower quadrants (p<0.05). Consequently, the relative distribution of incoming VT was preferentially directed into the lower lobes at low PEEP, primarily due to the loss of FRC in those lobes. Following ventilation at 10PEEP, the distribution of air at end-inflation was uniform across all quadrants and remained so regardless of the PEEP level. Uniform distribution of ventilation can be achieved by initiating ventilation with a high PEEP. After the lungs have aerated, small and stepped reductions in PEEP result in more uniform changes in ventilation.