Successive Hops Research Articles

Molten Guest-Mediated Metal-Organic Frameworks Featuring Multi-Modal Supramolecular Interaction Sites for Flame-Retardant Superionic Conductor in All-Solid-State Batteries.

The development of solid-state electrolytes (SSEs) with outstanding comprehensive performance is currently a critical challenge for achieving high energy density and safer solid-state batteries (SSBs). In this study, a strategy of nano-confined in situ solidification is proposed to create a novel category of molten guest-mediated metal-organic frameworks, named MGM-MOFs. By embedding the newly developed molten crystalline organic electrolyte (ML20) into the nanocages of anionic MOF-OH, MGM-MOF-OH, characterized by multi-modal supramolecular interaction sites and continuous negative electrostatic environments within nano-channels, is achieved. These nanochannels promote ion transport through the successive hopping of Li+ between neighbored negative electrostatic environments and suppress anion movement through the chemical constraint of the hydroxyl-functionalized pore wall. This results in remarkable Li+ conductivity of 7.1 × 10-4 S cm-1 and high Li+ transference number of 0.81. Leveraging these advantages, the SSBs assembled with MGM-MOF-OH exhibit impressive cycle stability and a high specific energy density of 410.5Wh kganode + cathode + electrolyte -1 under constrained conditions and various working temperatures. Unlike flammable traditional MOFs, MGM-MOF-OH demonstrates high robustness under various harsh conditions, including ignition, high voltage, and extended to humidity.

Design, synthesis, and lead optimization of piperazinyl-pyrimidine analogues as potent small molecules targeting the viral capping machinery of Chikungunya virus

The worldwide re-emerge of the Chikungunya virus (CHIKV), the high morbidity associated with it, and the lack of an available vaccine or antiviral treatment make the development of a potent CHIKV-inhibitor highly desirable. Therefore, an extensive lead optimization was performed based on the previously reported CHVB compound 1b and the reported synthesis route was optimized — improving the overall yield in remarkably shorter synthesis and work-up time. Hundred analogues were designed, synthesized, and investigated for their antiviral activity, physiochemistry, and toxicological profile. An extensive structure-activity relationship study (SAR) was performed, which focused mainly on the combination of scaffold changes and revealed the key chemical features for potent anti-CHIKV inhibition. Further, a thorough ADMET investigation of the compounds was carried out: the compounds were screened for their aqueous solubility, lipophilicity, their toxicity in CaCo-2 cells, and possible hERG channel interactions. Additionally, 55 analogues were assessed for their metabolic stability in human liver microsomes (HLMs), leading to a structure-metabolism relationship study (SMR). The compounds showed an excellent safety profile, favourable physicochemical characteristics, and the required metabolic stability. A cross-resistance study confirmed the viral capping machinery (nsP1) to be the viral target of these compounds. This study identified 31b and 34 as potent, safe, and stable lead compounds for further development as selective CHIKV inhibitors. Finally, the collected insight led to a successful scaffold hop (64b) for future antiviral research studies.

"RELATIONSHIP BETWEEN STRENGTH/POWER AND DYNAMIC BALANCE IN 1ST-YEAR UNDERGRADUATE STUDENTS – PILOT STUDY"

ABSTRACT. Aim: Examine the relationship between lower limb strength/power and dynamic balance, and whether lower limb strength differences influence balance. Methods: 85 subjects (mean age 20.14, ±0.44) - female (n=63) and male (n=22) 1st-year undergraduate students - participated in this study. Standing long jump and single leg triple hop jump tests were used to determine strength/power, and balance board was used to determine balance. Results: The statistical analysis has revealed no statistically significant correlation between lower limb strength and the average time on balance board after three essays (r = 0.102, df = 83, p = 0.35). As for the relationship between the difference in the scores of the three successive single leg hop jumps and the average time on balance board after three essays, no statistically significant correlation has been found in this case either (r = 0.136, df = 83, p = 0.21). The average score of hop jumps on right leg is (M = 412.54 cm) and the average score of hop jumps on left leg is (M = 403.07 cm); according to the statistical analysis, they differ significantly (t = 2.227, df = 84, p = 0.029). There is a significant difference (t = - 2.625, df = 84, p = 0.01) between the average time on balance board after the first essay (M = 24. 77) and the average time on balance board after the third essay (M = 27.21). Conclusions: In this study, the statistical analysis has revealed no statistically significant correlation between lower limb strength/power and balance. No statistically significant correlation has been found between lower limb strength difference and balance either. Balance board is important in balance development, as shown by the average scores of the three essays (M1 = 24.77, M2 = 26.52, M3 = 27.21).

Fork-Hook encryption policy based secured Data Centric Routing Gateway for proactive trust ware data transmission in WBSN

A wireless body sensor network is a collection of sensor nodes interconnected to monitor the patient to collect data and make cooperative on-route communication to medical healthcare. Due to increasing security issue on the transmission path, the data get leaked or false injected. So the security on routing is essential to make centralized routing with secure data transmission and protection against malicious activities. To resolve this problem of the security issue, to propose a Fork-Hook Encryption Policy based on Secured Data Centric Routing Gateway Protocol (FHEP-SDCRGP) to ensure the security depends on crypto blockchain policy for proactive trust ware routing creates encrypted transmission in WBSN. This initially verifies the lookup transmission from neighbor nodes and creates a cluster head path that demonstrates transition containing hop count. Then routing approach gets validated through Trust aware controller node key aggregation. Begin on the transmission medium, the packets get hashed through blockchain principle to encrypt through Fork-Hook Encryption Policy (FHEP) to create Successive Hop Index (SHI), and the private Key to each transmission node gets verified. This removes the sleeper cell nodes on the path that get non-authenticated to secure the data packets through the Sleeper node threading protocol. Each node receives verified through master node aggregation by Hop Count Rollback Node Aggregator (HCRNA) to transmit the encrypted packet from the cooperative routing node. After ascertaining the hop count matched broadcasting cluster head on controller node aggregation, the Key gets received from the authenticator to decrypt the data. The proposed system performs better in secure routing and authentication based on secured proactive cluster head aggregation. This attains higher verification on each flow, and the aggregator rollback acknowledgment improves the security and other existing approaches.

Analysis of Low-Frequency 1/f Noise Characteristics for MoTe2 Ambipolar Field-Effect Transistors.

Low-frequency electronic noise is an important parameter used for the electronic and sensing applications of transistors. Here, we performed a systematic study on the low-frequency noise mechanism for both p-channel and n-channel MoTe2 field-effect transistors (FET) at different temperatures, finding that low-frequency noise for both p-type and n-type conduction in MoTe2 devices come from the variable range hopping (VRH) transport process where carrier number fluctuations (CNF) occur. This process results in the broad distribution of the waiting time of the carriers between successive hops, causing the noise to increase as the temperature decreases. Moreover, we found the noise magnitude for p-type MoTe2 FET hardly changed after exposure to the ambient conditions, whereas for n-FET, the magnitude increased by nearly one order. These noise characteristics may provide useful guidelines for developing high-performance electronics based on the emerging transition metal dichalcogenides.

Unraveling the sub-100 fs ESIPT in 5-hydroxychromone using surface hopping simulations

We explore the structural, energetic and dynamic aspects of the excited-state intramolecular proton transfer process of 5-hydroxychromone using the trajectory surface hopping method. Gas-phase dynamics simulations show that the proton transfer on the “bright” S1 (ππ∗) is essentially a barrierless event and occurs on a timescale of about 24 fs. Our findings also demonstrate the possible proton transfer via “dark” S2 (nπ∗) after a successful hop from S1 to S2 via an accessible conical intersection that lies energetically and spatially nearby the Franck–Condon point of S1. An intrinsic barrier on S2 would delay the proton transfer dynamics (∼ 100 fs). The proton transfer occurs entirely via S1 in the presence of acetonitrile as a solvent. Computed energetics and geometries associated with key stationary points in the solvent environment are similar to gas-phase estimates, suggesting negligible solvation effects on the rapidity of the proton transfer via S1 in 5-hydroxychromone.

Hip-Hop in the Arab World and Kuwait

It is no wonder that young generations in the globe as well as in the Arab World are attracted to hip hop music that absorbs a load of incompatible emotions in a world of many conflicts and contradictions. The American roots of hip hop culture attract the young generation in the Arab World. This article examines examples from Arab and Gulf hip hop culture. A successful and distinguished Kuwaiti hip hop duo, Sons of Yusuf, has been interviewed to highlight their experience using bilingualism and reflecting on their traditions and culture. The group has worked hard to showcase the new factors that they have introduced to the knowledge of music in Kuwait and to the music life in the Arab World in general. Considering their lyrics and choices, Sons of Yusuf aim to express a Khaleeji identity that embraces history, tradition, and collective memory.

End-to-End Performance Optimization of a Dual-Hop Hybrid VLC/RF IoT System Based on SLIPT

In order to enhance the service provisioning to users in the indoor environment, a hybrid visible light communication (VLC)/radio-frequency (RF) Internet of Things (IoT) system is proposed based on simultaneous lightwave information and power transfer (SLIPT). A mobile user equipment, which serves as an off-the-grid relay, is able to extract information from the light-emitting diode source and then forward the processed information to the destination far away, thus dividing the signal transmission into two hops. Specifically, the optical signal received at the relay is separated into alternating current and direct current components for information decoding and energy harvesting, respectively, in the first hop. Then, the energy harvested is used to forward the processed source information to the destination by using RF in the second hop. Subject to the constraints imposed on both the average and the peak powers of the source, the end-to-end outage probability of the system is analytically derived in a closed form. On this basis, the minimization of the end-to-end outage probability is formulated as an optimization problem. This problem is then solved with a joint design of the peak amplitude and the direct current bias of the source transmitter, by trading-off between the performance of two successive hops. Simulation results demonstrate that by using the proposed optimal solution, the information flow and energy flow can be dynamically balanced, resulting in significant performance gains in terms of outage probability and throughput.

Selection and Preparation of Planting Material for Successful Hop Production in Florida

Hops (Humulus lupulus L.), an essential ingredient in beer, have potential to develop as a viable alternative crop in Florida. In our surveys, many breweries have expressed strong interest in using locally grown hops. However, hop production is plagued by many diseases, most of which were inadvertently introduced through the movement of contaminated planting material. The primary purposes of this new 7-page article are to prevent the introduction of these diseases into the state and to provide recommendations for selecting and preparing planting material for successful hop production in Florida. This publication of the UF/IFAS Horticultural Sciences Department is part of a larger series that will review the challenges of hop production, based on research experience at the UF/IFAS Gulf Coast Research and Education Center (UF/IFAS GCREC) in Balm, FL.https://edis.ifas.ufl.edu/hs1381

Hop test does not correlate with neuromuscular control during drop vertical jump test: A prognostic comparative study utilizing healthy subjects

Background: A functional hop test is an established tool used to assess performance prior to return to sport. The effect of demographics, limb strength and flexibility, and neuromuscular control on hop test performance is not fully understood. Our hypothesis is that successful hop testing strongly (r>0.7) correlates with increased strength and neuromuscular control in a healthy athletic population. Methods: In this prospective clinical performance evaluation, 25 asymptomatic, active individuals participated. Flexibility measurements were recorded with a standard goniometer, strength measurements were recorded with a handheld dynamometer, and kinematic data were collected during a drop vertical jump (DVJ) using a 14-camera 3D markerless motion analysis system. Frontal plane knee abduction angle and hip rotation were measured during DVJ. Each participant underwent triple hop, cross hop, and timed 6-m hop tests. Pearson product moment correlation (moderate correlation: r value 0.4–0.7, strong correlation: r>0.7) analysis was used to assess the relationship between performance on hop tests and gender, body mass index, strength and flexibility, and frontal plane knee abduction angle and hip rotation on DVJ. Results: Hip abduction strength, external rotation strength, quadriceps and hamstring strength each had moderate correlations to the triple hop test (r values=0.52, 0.62, 0.46, 0.50, respectively) and the cross-hop test (r values=0.56, 0.65, 0.54, 0.55, respectively). Hop test performance did not strongly correlate with frontal plane projection angle and hip internal rotation. Conclusions: Functional hop tests correlated with strength but had weak to minimal correlation with neuromuscular control. Individuals with neuromuscular deficits may still do well on standard hop tests. Level of Evidence: Level III.

Theoretical modeling for performance analysis of IEEE 1901 power-line communication networks in the multi-hop environment

As one of the most promising networking technologies, power-line communication (PLC) networks have been gradually used not only in home networking systems but also in industrial IoT (Internet of things). Current studies of PLC medium access control (MAC) protocol (i.e., IEEE 1901) only focus on the single-hop environment; however, in practical industrial IoT and home access communication systems, PLC networks generally utilize a multi-hop architecture. In addition, due to the difference in the MAC standard between 802 series and 1901, existing analytical models of multi-hop IEEE 802.11 wireless networks are not suitable for multi-hop IEEE 1901 PLC networks. In this paper, we propose a theoretical model for performance analysis of multi-hop IEEE 1901 PLC networks, where the impacts of traffic rate (containing relay traffic), buffer size, deferral counter process of 1901, hidden terminal problem and multi-hop environment are comprehensively considered. The modeling process is divided into two parts. In the local modeling part, we construct a brand-new Markov chain model to investigate the carrier sense multiple access with collision avoidance process of IEEE 1901 protocol under the multi-hop environment. In the coupling queueing modeling part, we employ queueing theory to analyze the packet transmission procedure between successive hops. On the basis, we derive the closed-form expressions of throughput, medium access delay, packet blocking probability, end-to-end successful transmission delay and goodput. Through extensive simulations, we verify that our theoretical model can accurately estimate the MAC performance of IEEE 1901 PLC networks in the multi-hop environment.

Role of short- and long-range ordering on diffusion in Ni-Al alloys

The varying degrees of short- and long-range order exhibited by multicomponent solids complicates a first-principles calculation of nondilute diffusion coefficients. Temporal and spatial variations in the local degree of order affect the migration barriers of individual hops and can result in strong correlations between successive hops that ultimately affect macroscopic transport coefficients. Here we report on a first-principles study of diffusion in Ni-rich Ni-Al alloys. We used cluster expansion Hamiltonians to describe the energies of the end states and migration barriers of each hop. Kinetic Monte Carlo simulations were performed to calculate macroscopic transport coefficients. Variations in the degree of ordering are shown to play a significant role in affecting diffusion coefficients. While Al has a higher mobility than Ni in the disordered Ni-rich fcc solid solution, it becomes significantly less mobile in the ordered $L{1}_{2}\phantom{\rule{4pt}{0ex}}{\ensuremath{\gamma}}^{\ensuremath{'}}$ phase due to strong thermodynamic tendencies that keep Al trapped to disconnected sublattice sites.

Performance analysis of multi‐hop multi‐branch frequency‐selective channel for DF relaying

In this work, the authors have explored the average bit error rate (BER) and ergodic capacity (EC) of a frequency-selective channel consisting of multi-hop and multi-branch (MHMB). Each hop consists of multiple paths and signal travels in successive hops using decode and forward (DF) relaying. The channel is assumed to be log-normal distributed. Numerical integration (NI) formulations based on the Gauss-quadrature rule representation of the moment generating function of log-normal distribution have been derived for both average BER and EC for multi-hop and MHMB cooperative communication framework using maximal ratio combining and selection combining (SC) techniques at receiver. Results are obtained for a variable number of hops and branches. Excellent matching between Monte Carlo simulation and NI plots validate the accuracy of the proposed formulations. The contribution of this work to the existing research scenario is two-fold: (i) to the best of the authors' knowledge, this is a first attempt to study a generic MHMB framework of a log-normal distributed frequency-selective channel. (ii) DF which is a more practical relaying protocol has not been explored till date for analysis of a log-normal distributed MHMB network. Both of these aspects make this work pertinent.

Physical properties of Ag/Ca doped Lantanium manganite

La0.6Ca0.3Ag0.1MnO3 system has been synthesized using the cheap solid–solid process. Structural analysis indicates that the sample exhibits a single phase of intragranular. Electrical and dielectric data, over a wide temperature range and frequencies have been recorded with impedance spectroscopy. We visualize the conductivity, whose activation energy is low, as a successive hopping of electrons as polaron does. Further, the conductivity is governed by the small polaron hopping model at higher temperature region while it fits well with the variable range hopping model at a lower temperature range. Dielectric data has been represented in different alternative complex formalisms, from which complementary information has been extracted. The complex impedance diagram suggests the contribution of only two active microstructures, ruling out the electrode polarization effect. We adopt the spectrum of the imaginary component of the electric modulus M″ to distinguish long range hopping from short range hopping. The relative permittivity spectrum permits to identify the possibility of the existence of electric polarizations. Further, it reveals colossal static dielectric constant, which makes it suitable for multitude potential applications in electronic industrial fields.

A Machine Learning-Based Protocol for Efficient Routing in Opportunistic Networks

This paper proposes a novel routing protocol for OppNets called MLProph, which uses machine learning (ML) algorithms, namely decision tree and neural networks, to determine the probability of successful deliveries. The ML model is trained by using various factors such as the predictability value inherited from the PROPHET routing scheme, node popularity, node's power consumption, speed, and location. Simulation results show that MLProph outperforms PROPHET+, a probabilistic-based routing protocol for OppNets, in terms of number of successful deliveries, dropped messages, overhead, and hop count, at the cost of small increases in buffer time and buffer occupancy values.

The Relationship Between Side Hop Test Endurance And Energy Absorption

Many factors are associated with an athlete being able to safely return to sport (RTS). Frontal plane control and endurance in the frontal plane is recognized as important factor in RTS. The ability to absorb energy while fatigued is critical to help dissipate forces and minimize injury risk. Current RTP guidelines do not evaluate fatigue and power absorption. A new 30-second endurance side hop test could provide a means of clinically evaluating this ability. PURPOSE: Compare the change in energy absorption over a 30-second side hop test in healthy subjects. METHODS: 17 healthy subjects (11 M, ages 22.4 ± 3.14, BMI 22.96 ± 3.06) with no prior lower extremity injuries performed an instrumented single limb lateral hops between two force plates 15.24 cm apart as many times as possible in 30 seconds. Errors were subtracted from total successful hops and included landing between the force plates or putting the non-stance limb down. The change in energy absorption from beginning to the end of the test was also calculated. Pearson product moment correlation was used to evaluate the relationship between the average number of hops to the change energy absorption over 30 seconds. We also assessed the difference in hops between those who maintained versus those who had a reduction in power absorption with an independent samples t test. RESULTS: Subjects performed an of 29.4± 6.6 lateral hops over 30 seconds. There was a strong, significant correlation between the number of hops to energy absorption (r=0.68, p= 0.003). There was also a significant difference (p=0.04) in the number of hops between those who maintained energy absorption (32.3± 4.4 J) versus those who did not (26.1± 7.3 J). CONCLUSIONS: This 30-second side hop endurance test was significantly correlated to energy absorption. Those who performed the best were able to maintain energy absorption throughout the testing protocol. Potentially, the ability to maintain the ability to absorb energy while fatigued may reduce of injury, as these athletes are better able to attenuate loads. Having established the relationship to energy absorption, future studies should evaluate the test’s relevance to injury prediction.

Development of a Lateral Hop Endurance Test

Functional tests for patients attempting to return to sports, typically focus on sagittal plane movement such as a hop test. Additionally, most functional tests do not have an endurance component to them. Many injuries involve aberrant frontal plane control and occur later in a game situation. The development of a lateral endurance hop may prove useful to identify at risk athletes. As a first step, we sought to determine the reliability of a newly developed lateral hop test. PURPOSE: The purpose of this study was to evaluate the reliability of a new lateral hop endurance test. METHOD: 19 healthy subjects (11 M, ages 22.4 ± 3.1, BMI 22.9 ± 3.0) with no prior lower extremity injuries completed 30 second intervals of single legged lateral hopping with the targets separated by 15.24 centimeters. Performance was measured by counting the number of times the subject was able to hop completely over and back. An error was classified as putting a foot down or landing on the target and not counted. Reliability between raters as well as within and between days was assessed using an Intraclass Correlation Coefficient (ICC) and Pearson Product Moment Correlation. RESULTS: The average number of successful hops was (29.20 ±6.35 hops). Between rater reliability (ICC>0.99), between day reliability (ICC=0.94), and correlation between days (r=0.89, p=<0.001) were all excellent. CONCLUSION: The 30 second lateral hop endurance test had excellent reliability between raters and between days as well as a strong correlation between days. Having established the reliability of this test between days and rater, subsequent studies will evaluate differences within injured athletes.

Briefs and Hot Brown Honey: Alternative Bodies in Contemporary Circus

Briefs and Hot Brown Honey: Alternative Bodies in Contemporary Circus

Dynamic spin filtering at the Co/Alq3 interface mediated by weakly coupled second layer molecules.

Spin filtering at organic-metal interfaces is often determined by the details of the interaction between the organic molecules and the inorganic magnets used as electrodes. Here we demonstrate a spin-filtering mechanism based on the dynamical spin relaxation of the long-living interface states formed by the magnet and weakly physisorbed molecules. We investigate the case of Alq3 on Co and, by combining two-photon photoemission experiments with electronic structure theory, show that the observed long-time spin-dependent electron dynamics is driven by molecules in the second organic layer. The interface states formed by physisorbed molecules are not spin-split, but acquire a spin-dependent lifetime, that is the result of dynamical spin-relaxation driven by the interaction with the Co substrate. Such spin-filtering mechanism has an important role in the injection of spin-polarized carriers across the interface and their successive hopping diffusion into successive molecular layers of molecular spintronics devices.

Insights into the Lithium-Ion Conduction Mechanism of Garnet-Type Cubic Li5La3Ta2O12 by ab-Initio Calculations

Garnet-type solid electrolytes are a class of materials that could potentially revolutionize Li-ion battery technology. In this work, ab-initio-based MD simulations have been performed to investigate the ion dynamics in pure garnet-type cubic Li5La3Ta2O12 (LLTaO) over the temperature range from 873 to 1773 K. A strong tendency for disorder in the Li sublattice was verified for LLTaO that explains the relative ease of stabilizing the reported cubic phase for this material. The Li+ conduction mechanism was determined to be facilitated by a cooperative hopping process characterized by long, multiple-site successive hops with a very small time scale for fluctuations at intermediate positions. A comparative study is also carried out between LLTaO and garnet-type Li7La3Zr2O12 (LLZrO), another candidate solid electrolyte.