Forward Direction Research Articles

Evaluating the Balancing Ability of Older Adults with Diabetes Mellitus Using the Multi-directional Reach Test.

The incidence of elderly people experiencing falls is currently increasing, which results in serious medical issues, such as fear of falling, limited physical activity, disability, and bone fractures, especially hip fractures. This study aimed to investigate balancing ability using a multi-directional reach test (MDRT) in older adults with and without diabetes mellitus. 72 older adults with and without diabetes mellitus were recruited, and divided into two groups, including older adults without diabetes mellitus (n = 36) and older adults with diabetes mellitus (n = 36). All subjects completed all directions of the MDRT. There were no significant differences in MDRT scores in all directions between the two groups (p>0.05). Both groups achieved the highest MDRT scores in the forward direction. In contrast, the two groups had the lowest scores of MDRT in a backward direction. Furthermore, older adults with diabetes mellitus had lower MDRT scores in all directions than older adults without diabetes mellitus. The current study indicated that MDRT could be used to investigate the ability of balance in individuals with diabetes mellitus.

Entropy production from waiting-time distributions for overdamped Langevin dynamics

For a Markovian dynamics on discrete states, the logarithmic ratio of waiting-time distributions between two successive, instantaneous transitions in forward and backward direction is a measure of time-irreversibility. It thus serves as an entropy estimator, which is exact in the case of a uni-cyclic network. We adopt this framework to overdamped Langevin dynamics, where such transitions have finite duration. By introducing milestones based on the observation of a particle at at least two milestones and an additional third event, we identify an entropy estimator that becomes exact for driven motion along a one-dimensional potential.

Principle and experimental study of a combined teardrop and heart-shaped channel bluffbody valveless piezoelectric pump.

In this study, we have developed a piezoelectric pump with a combined teardrop- and heart-shaped channel based on the Coanda effect and bionics principle. The bluffbody consists of teardrop- and heart-shaped channels. The vibration and the pump flow rate are evaluated theoretically, and the flow conditions under different bluffbody heights and different main channel widths are simulated. The theoretical and simulation results show that the pump has uneven resistance to flow in forward and reverse directions, and the height of the teardrop bluffbody and the width main channel affect the flow in the channel. Test data show that under the same pressure, when the main channel is 5mm and the bluffbody height is 8mm, the pump flow rate is 460.8 ml/min. The pump alleviates the serious backflow problem through the fluid blocking structure and is expected to become an active driver of microfluidic devices.

Design, Fabrication and Testing of A Novel Thermally-Actuated Tesla Valve (TATV): A Hybrid Microvalve

Abstract A novel thermally-actuated hybrid microvalve (similar to a Tesla Valve configuration) was designed, fabricated, assembled, and tested using soft lithography-based approaches. The modified design integrates the "normally open and closed" hybrid configurations of Tesla Valves with a thermo-pneumatic (or thermal-hydraulic) actuator microfabricated in-situ that modulates the diodicity of the microvalve apparatus in the microfluidic chip. Diodicity (Di) is defined as the ratio of flow rate in the forward direction to that of the reverse direction (for a constant value of pressure drop that is imposed on a microvalve device). The results from the study successfully demonstrated the operation of an array of Tesla Valves that are normally open in forward direction and marginally closed in reverse direction at room temperature (i.e., with Di > 1, the flow resistance values were different when the inlet and outlet ports were swapped). When the microfluidic chip was heated (at steady-state conditions with a nominal temperature of ~30°C), the diodicity virtually vanished (i.e., Di ≈ 1) resulting in both reverse and forward directions being normally open (or having the same flow resistance - irrespective of the flow direction).

Josephson diode effect in junctions of superconductors with band asymmetric metals

At interfaces connecting two superconductors (SCs) separated by a metallic layer, an electric current is induced when there is a disparity in the phases of the two superconductors. We elucidate this phenomenon based on the weights of the Andreev bound states associated with the states carrying currents in forward and reverse directions. Typically, current phase relation (CPR) in Josephson junctions is an odd function. When time reversal and inversion symmetries are broken at the junction, CPR ceases to be an odd function and the system may exhibit Josephson diode effect. This phenomenon has been studied in spin orbit coupled systems under an external Zeeman field wherein the magnetochiral anisotropy is responsible for the Josephson diode effect. Recently introduced the band asymmetric metal (BAM) model presents a novel avenue, featuring an asymmetric band structure. We investigate DC Josephson effect in SC-BAM-SC junctions and find that band asymmetry can lead to Josephson diode effect and anomalous Josephson effect. We explain the mechanism behind these effects based on interference of plane wave modes within the Bogoliubov de-Genne formalism. We calculate diode effect coefficient for different values of the parameters.

A GaN-based SOI plasmonic nanolaser design with high-output power

Due to its unique optical and electrical properties, gallium nitride (GaN) exhibits great promise for nanolaser cavities. These characteristics include high electron mobility, wide bandgap energy, and a high refractive index. Moreover, GaN exhibits remarkable thermal stability, making it appropriate for high-power laser applications. The choice of active medium material can significantly impact the laser’s performance, including its wavelength, output power, and efficiency. This work designed and numerically demonstrated a GaN-WG built-in Si O2 substrate with an input and output Si-waveguide nanolaser. These nanolasers lase multi-output wavelengths in both directions (forward and backward) at 1680 and 1750 nm, respectively. The pump power is 800 nm. The GaN-waveguide material, when used in nanolaser cavity design, gives many different advantages, like concentration of the Gaussian envelope and improved polarization depending on rate (PDR). Increasing lasing efficiency by 76.6% in the forward direction and 96.7% in the backward direction. Get a low lasing threshold of approximately 200 μW in the forward direction and 180 μW in the μW backward direction. Finally, improved the output laser power in both directions (460 μW and 600 μ W) in the forward and backward directions, respectively.

Dynamics of electron capture in positron‐hydrogen scattering under dense semi‐classical plasmas

AbstractThe scattering dynamics of electron capture in ‐H(1 s) scattering under dense semi‐classical plasma (DSCP) environments has been investigated theoretically. Coupled multi‐channel two‐body Lippmann‐Schwinger equations have been solved by retaining +H(1 s) and p + Ps(1 s) channels to calculate the cross sections (CS) of the electron capture process at intermediate and high incident energies. The effective interaction of the plasma charged particles is modelled by a pseudopotential which is a function of two parameters, namely the plasma screening strength and the de Broglie wavelength. A detailed study is made to explore the changes in the CSs of the above‐mentioned process with respect to the variation in the plasma screening strength and de Broglie wavelength. Significant changes are found to take place, when the screening strength and the de Broglie wavelength are varied. Specifically, the sharp minimum in the differential CS moves toward the forward direction with increasing de Broglie wavelength at a given screening strength.

Probing positivity at the LHC with exclusive photon-fusion processes

By tagging one or two intact protons in the forward direction, it is possible to select and measure exclusive photon-fusion processes at the LHC. The same processes can also be measured in heavy ion collisions, and are often denoted as ultraperipheral collisions (UPC) processes. Such measurements open up the possibility of probing certain dimension-8 operators and their positivity bounds at the LHC. As a demonstration, we perform a phenomenological study on the γγ → ℓ+ℓ− processes, and find out that the measurements of this process at the HL-LHC provide reaches on a set of dimension-8 operator coefficients that are comparable to the ones at future lepton colliders. We also point out that the γq → γq process could potentially have better reaches on similar types of operators due to its larger cross section, but a more detailed experimental study is need to estimate the signal and background rates of this process. The validity of effective field theory (EFT) and the robustness of the positivity interpretation are also discussed.

Arg40 is critical for stability and activity of Adenylosuccinate lyase; a purine salvage enzyme from Leishmania donovani

Purine salvage enzymes have been of significant interest in anti-Leishmanial drug development due to the parasite's critical dependence on this pathway for the supply of nucleotides in the absence of a de novo purine synthesis pathway. Adenylosuccinate lyase (ADSL) one of the key enzymes in this pathway is a homo-tetramer, where the active site is formed by residues from three distinct subunits. Analysis of the subunit interfaces of LdADSL, revealed a conserved Arg40 forming critical inter-subunit interactions and also involved in substrate binding. We hypothesized that mutating this residue can affect both the structural stability and activity of the enzyme. In our study, we used biochemical, biophysical, and computational simulation approaches to understand the structural and functional role of Arg40 in LdADSL. We have replaced Arg40 with an Ala and Glu using site directed mutagenesis. The mutant enzymes were similar to wild-type enzyme in secondary structure and subunit association. Thermal shift assays indicated that the mutations affected the protein stability. Both mutants showed decreased specific activities in both forward and reverse directions with significantly weakened affinities towards succinyl-adenosine monophosphate (SAMP). The mutations resulted in changes in C3 loop conformation and D3 domain rotation. Consequently, the orientation of the active site amino acid residues changed resulting in compromised activity and stability. Studies so far have majorly focused on the ADSL active site for designing drugs against it. Our work indicates that an alternative inhibitory mechanism for the enzyme can be designed by targeting the inter-subunit interface.

Heat and concentration analysis of two-layered muco-ciliary third grade fluid flow in human airways

Understanding the mechanisms involved in the movement and clearance of mucus within the human airways is important from a physiological perspective. A mathematical model of muco-ciliary two-layered fluid flow in a finite two-dimensional channel is proposed. Due to the presence of both the airway ciliary layer (ACL) and the periciliary liquid layer (PCL) in airways epithelial cells, the two-layered model is adopted. The third grade fluid models is used to characterize the viscoelastic nature of mucus secreted in the airways. The mathematical modeling of two-layer flow problem is simplified by using long wavelength and small Reynolds number approximation. A formulated set of partial differential equations (PDEs) is solved for series-form solutions of velocity, temperature, concentration, and pressure gradient by using the Adomian decomposition method (ADM). The analysis delineated that with an increase in pressure gradient at airways entrance ξ the velocity and temperature increases while concentration decreases. Deborah numbers impact ACL and PCL velocities differently, with De(A) influencing flow direction and De(P) causing fluid to flow faster in the forward direction. It also emphasizes the significance of the rate of thermal diffusion, viscous dissipation, and relaxation time. The results showed that the suggested two-layered muco-ciliary model provides a better description of mucus transport in the human airways. The pressure gradient at the airways entrance has a significant impact on mucus transport through the airways.

A Sheet-Shaped Transforming Robot That Can Be Thrown from the Air.

In this paper, we describe a sheet-shaped throwable transforming robot. Sheet-type robots can change their shape to perform tasks according to the situation. Therefore, they are expected to be useful in places with many restrictions, such as disaster sites. However, most of them can only move slowly on the ground. Therefore, in order to actually deliver the robot to the disaster site, it must be carried manually. To solve this problem, we are developing a sheet-shaped robot that can be thrown from the sky. Previously developed prototypes could only move in the forward direction, and the transition from falling to walking was complicated and uncertain. In this paper, we report on a new prototype that improves on these shortcomings.

Miniaturized leaky-wave antenna with backward-to-forward beam scanning and suppressed open stop-band based on substrate-integrated plasmonic waveguide

This work presents a theoretical design and experimental demonstration of a novel miniaturized leaky-wave antenna (LWA) using composite waveguide based on substrate-integrated plasmonic waveguide (SIPW). The SIPW is designed by embedding hybrid dual spoof surface plasmon polariton (SSPP) structure into a three-layer substrate integrated waveguide (SIW). Due to the slow-wave effect of SIPW, the proposed miniaturized composite waveguide forms slowed phase velocity and decreased lower cutoff frequency. To excite backward-to-forward beam scanning mode and suppress the open stop-band, an asymmetric sinusoidal modulated structure is introduced to the surface of the composite waveguide. The experimental results indicate that the proposed SIPW-based LWA can achieve continuous beam scanning from the backward to the forward direction within the bandwidth of 10.6-13.7 GHz, passing through the broadside at 11.6 GHz.

Does the Workload Change When Using an Impact Wrench in Different Postures?—A Counter-Balanced Trial

Awkward hand-arm posture and overhead work increase the risk of musculoskeletal symptoms. These adverse health effects can also be caused by additional workloads such as hand-arm vibration exposure while carrying or holding a power tool. This pilot trial investigated posture and muscle activity of 11 subjects while using an impact wrench for three working directions: upwards, forwards and downwards. Although the vibration exposure did not show notable differences in the magnitude (4.8 m/s2 upwards, 4.4 m/s2 forwards and 4.7 m/s2 downwards), postural behavior and the muscle activity showed significantly higher workloads for working upwards compared to forwards direction. The muscle activity results for working downwards also showed elevated levels of muscle activity due to the awkward wrist posture. The results demonstrate that not only the working direction but also more importantly the arm, wrist and head posture need to be considered while investigating hand-arm vibration exposure.

Detection prospects of long-lived quirk pairs at the LHC far detectors

We examine the sensitivity reaches of several LHC far detectors, such as FASER2, MATHUSLA, ANUBIS, SND@LHC, and FACET, to five simplified quirk scenarios. We include the next-to-leading order QCD corrections in our simulation of quirk events, which enhance the total production rate and increase the fraction of events in the forward direction for most cases. We calculate the timescales for the quirk pair to lose energy through radiations and for the quirk pair annihilation. Our results show that these far detectors can offer promising probes to the quirk scenario, complementing the searches at the main detectors. Especially, FACET and FASER2 detectors can surpass the majority of searches conducted at the LHC main detector, with the exception of the HSCP search, for the color-neutral quirk E. Published by the American Physical Society 2024

Abstract PO5-08-06: Metabolic shift to serine pathway induced by lipids confers oncogenic properties in non-transformed breast cells

Abstract Introduction. Oncogenic factors that are local/in-breast are of great interest as they may be more specifically targetable for breast cancer prevention than systemic factors. We have identified a lipid metabolism gene signature that is enriched in breast tissue at risk for estrogen negative breast cancer (ER- BC). Utilizing the medium chain fatty acid Octanoic acid (OA) to probe lipid metabolism in non-transformed breast epithelial cells, we observed increased flux through several metabolic reactions and altered histone methylation with consequent changes in gene expression (e.g. neural genes). Neuronal signaling and regulatory circuits are observed in cancer cells of multiple origins, not just ones with ontological relationships to neurons. We hypothesize that the first and rate limiting step in the de novo serine pathway, which is catalyzed by Phosphoglycerate Dehydrogenase (PHGDH) is key to these observations. In the forward direction, PHGDH participates in the serine, one-carbon, glycine (SOG) and methionine pathways that produce the methyl donor S-adenosylmethionine (SAM) and in the reverse direction produces the oncometabolite 2-Hydroxyglycerate (2-HG). Methods. Non-transformed MCF-10A cells exposed to OA were utilized for U13C-glucose tracing. SAM and 2-HG concentrations following treatment with OA ± PHGDH inhibitor were measured by liquid chromatography. CUT&RUN for H3K4me3 was performed and genes affected by OA (PMID: 28263391) were compared with OA-responsive peaks. Single cell RNA-sequencing was carried out using breast microstructures derived from reduction mammoplasty tissue exposed to vehicle or OA. Microstructures were dissociated into single cells and sequenced using the 10x Genomics platform. The digital expression matrix file containing UMIs were analyzed with Seurat. Alkaline comet assay was performed to detect DNA breaks. Results. U13C-glucose tracing in presence of OA revealed that one-carbon-THF was redirected to the methionine cycle increasing flux to methylation. Concentrations of SAM and 2-HG increased after 15- and 30-min OA exposure, respectively; PHGDH inhibitor blocked these increases. H3K4me3 CUT&RUN revealed 661 differential peaks (FDR < 0.05) comparing OA to control. 73% of H3K4me3 OA-associated peaks were in regulatory regions of OA-induced genes (FDR < 0.01), these genes are involved in neural pathways, EMT and ER- BC. Motif analysis revealed an overrepresentation of binding sites for transcription factors ATF3/4 (p < 0.05), which are regulators of the serine pathway. Single cell RNA-sequencing revealed OA not only affected the distribution of cell subpopulations but also modulated the expression of many genes within each subcluster. The percentage of luminal progenitor subcluster 3 increased upon OA from less than 1% to about 13%. Within basal subcluster 3, OA drives the expression of ATF3, along with two of the enzymes in the de novo serine pathway: PHGDH and PSAT1. Alkaline comet assay showed DNA breaks in OA- and control 2-HG- treated cells. Conclusions. Metabolism of OA in preference to glucose and glutamine results in a metabolic shift toward the serine pathway increasing the production of SAM and 2-HG, with implications for oncogenesis: 1. SAM production results in epigenetic fostered plasticity leading to reprogramming/selecting cells that express genes consistent with a neural/neural crest-like state. These co-opted neuronal regulatory mechanisms can make critical contributions to the acquired functional capabilities that drive cancer development. 2. 2-HG exposure results in appearance of DNA breaks, which are likely consequent to the inhibition of the alpha-ketoglutarate-dependent dioxygenases KDM 4A/B by 2-HG. Their catalytic activity is required for homologous recombination repair; inhibition results in metabolic “BRCAness”. Citation Format: Mariana Bustamante Eduardo, Gannon Cottone, Shiyu Liu, Maria Paula Zappia, Elizaveta V. Benevolenskaya, Abul Bashar Mir Md. Khademul Islam, Maxim V. Frolov, Seema Khan, Susan Clare. Metabolic shift to serine pathway induced by lipids confers oncogenic properties in non-transformed breast cells [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-08-06.

An Ultra-soft Thermal Diode

The controlling of heat flow direction stands as a prominent methodological approach within the domain of thermal management, and this can be accomplished through the utilization of thermal diodes. However, if the thermal diode lacks mechanical compliance, hindering its intimate contact with heat source/sink surfaces, the thermal rectification performance is limited. In this work, we propose a method to solve the mechanical compliance problem that is introducing phase change material (PCM) consisting of dual alkanes (hexadecane and paraffine wax) and polyurethane to fabricate the heterojunction thermal diode. The fabricated thermal diode exhibits an ultra-soft mechanical feature, with a low elastic modulus of 0.4 KPa and >300 % elongation until failure – the best values reported to date for thermal diodes. The measured thermal rectification factor is as high as 1.42 – in line with the theoretical model prediction. Molecular dynamic simulations reveal that the thermal rectification mechanism of the PCM-based thermal diode originates from the crystal-amorphous phase transition of the hexadecane terminal as the temperature bias flips. Therefore, the heat flow in the forward direction is greater than the flux in the reverse direction. A series of experiments and finite element analyses are employed to verify the feasibility of thermal diodes for applications in real contexts like the civil engineering.

Quantitative characterization of crude oil mobilization in microscopic pores during forward and reverse flooding in tight sandstone reservoirs using various fracturing fluid systems

In the transition from conventional to unconventional oil and gas exploration, the focus on tight sandstone reservoirs has grown due to their complex microscopic pore structures, narrow pore throats, and high capillary pressures. These characteristics often lead to the retention of fracturing fluids post-fracturing, hindering fluid recovery and reducing crude oil extraction efficiency. To address these issues, this study employed a combination of microscopic displacement experiments and nuclear magnetic resonance (NMR) analyses to investigate oil displacement mechanisms at the microscale in tight sandstone reservoirs. The experimental setup involved testing three core samples using distinct fracturing fluid systems: a guar gum-based system (System I), an EM30+ + guar gum water-based system (System II), and a CNI (Carbon Nanotechnologies Inc) nano variable-viscosity slick water-based system (System III). The study aimed to assess the impact of these different fracturing fluid systems on oil displacement efficiency in both forward and reverse directions. Results revealed that forward oil displacement efficiencies for Systems I to III were 26.86%, 33.3%, and 33.43%, respectively. In contrast, reverse displacement efficiencies were slightly higher at 28.9%, 37.5%, and 38.34%. Overall, Systems II and III outperformed System I in terms of oil displacement efficiency. The study also found that in cores with large pores, forward displacement predominantly mobilized crude oil, while reverse displacement was more effective in smaller pores. This trend was consistent in cores exhibiting bimodal pore distributions. However, in unimodal cores, small pores were significantly impacted in both directions. Notably, System III demonstrated a remarkable efficiency in mobilizing crude oil within smaller pores.

Bingham plastic fluids flow analysis in multimembranes fitted porous medium

A mathematical analysis is presented for the flow of a Bingham plastic fluid propelled by the multi-membranes pumping mechanism through porous media. Two successive membranes with different amplitude, diameter, and phase lag, are fitted at the upper wall of the channel, and the lower wall is stationary. Due to the simultaneous propagation of both membranes, the pressure is generated at the membrane's position, which helps in propelling the fluids in forward and backward directions depending upon the compression and expansion cycles of the membranes. The low Reynolds number assumption and lubrication theory are utilized to linearize the governing equations, which are further analytically derived, and then employing MATLAB codes to compute the illustrations for the interpretation of the results. The effects of key parameters like plug flow region, pore size and diameter of membranes on the velocity field, wall shear stress, pressure gradient, fanning friction factor, head loss and particle trajectories, are analysed in the microchannel. Results of the present model conclude that the geometrical properties of membranes, rheological properties of fluids and porosity of the medium significantly alter the flow and pumping characteristics which give valuable insights for the design of micro-valve less pumping actuators to be aimed at controlling microscale transport processes in various medical diagnoses and treatments.

Prediction of Airport Taxiway Settlement based on CNNBiLSTM-Attention

The accurate real-time prediction of complex time series in airport runway settlement is crucial. In order to achieve precise and reliable predictions of runway surface settlement, considering the nonlinear and time-dependent characteristics of settlement data under the coupling effects of dynamic loads, water levels, and other factors, a CNN-BiLSTM-Attention approach is proposed. This method first employs Convolutional Neural Networks (CNN) to extensively extract local temporal features from the input sequences. Subsequently, the extracted local temporal features are input to BiLSTM layers to learn the features of the sequences both in the forward and reverse directions. Finally, the output of the BiLSTM layers is fed into an attention mechanism layer. By computing attention weights, crucial information in the input sequences is weighted and added to enhance the model’s focus on key information. The final settlement prediction is then generated through a fully connected layer. To validate the proposed method, field settlement monitoring data from Runway L at Hangzhou Xiaoshan Airport are utilized as an engineering case study. The results indicate that the combined model captures local features of settlement sequences more effectively with a smaller dataset, achieving higher accuracy compared to a standalone BiLSTM model.

The FASER detector

FASER, the ForwArd Search ExpeRiment, is an experiment dedicated to searching for light, extremely weakly-interacting particles at CERN's Large Hadron Collider (LHC). Such particles may be produced in the very forward direction of the LHC's high-energy collisions and then decay to visible particles inside the FASER detector, which is placed 480 m downstream of the ATLAS interaction point, aligned with the beam collisions axis. FASER also includes a sub-detector, FASERν, designed to detect neutrinos produced in the LHC collisions and to study their properties. In this paper, each component of the FASER detector is described in detail, as well as the installation of the experiment system and its commissioning using cosmic-rays collected in September 2021 and during the LHC pilot beam test carried out in October 2021. FASER has successfully started taking LHC collision data in 2022, and will run throughout LHC Run 3.