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The single-molecule magnet (SMM) is demonstrated here to transform conventional magnetic tunnel junctions (MTJ), a memory device used in present-day computers, into solar cells. For the first time, we demonstrated an electronic spin-dependent solar cell effect on an SMM-transformed MTJ under illumination from unpolarized white light. We patterned cross-junction-shaped devices forming a CoFeB/MgO/CoFeB-based MTJ. The MgO barrier thickness at the intersection between the two exposed junction edges was less than the SMM extent, which enabled the SMM molecules to serve as channels to conduct spin-dependent transport. The SMM channels yielded a region of long-range magnetic ordering around these engineered molecular junctions. Our SMM possessed a hexanuclear [Mn6(μ3-O)2(H2N-sao)6(6-atha)2(EtOH)6] [H2N-saoH = salicylamidoxime, 6-atha = 6-acetylthiohexanoate] complex and thiols end groups to form bonds with metal films. SMM-doped MTJs were shown to exhibit a solar cell effect and yielded ≈ 80 mV open-circuit voltage and ≈ 10 mA/cm2 saturation current density under illumination from one sun equivalent radiation dose. A room temperature Kelvin Probe AFM (KPAFM) study provided direct evidence that the SMM transformed the electronic properties of the MTJ's electrodes over a lateral area in excess of several thousand times larger in extent than the area spanned by the molecular junctions themselves. The decisive factor in observing this spin photovoltaic effect is the formation of SMM spin channels between the two different ferromagnetic electrodes, which in turn is able to catalyze the long-range transformation in each electrode around the junction area. 

The intra-molecular coupling within multiple units of paramagnetic molecules can produce various effects on molecular spintronics devices (MSD). The effect of the nature of the strong magnetic coupling between a multi-segmented molecule with two ferromagnetic (FM) electrodes is unexplored. Such knowledge is of critical importance for magnetic tunnel junction-based molecular spintronics devices (MTJMSD). MTJMSD architecture experimentally allows very strong bonding between complex molecules and ferromagnetic electrodes. In our prior studies, we have extensively studied the atomic analog of the single molecular magnet. That means whole molecular geometry and internal features were approximated to appear as one atom representing that molecule. To advance the understanding of the impact of internal molecular structure on MTJMSD, we have focused on multi-segmented molecules. This research aims to fill the knowledge gap about the intramolecular coupling role in the magnetic properties of the MTJMSD. This study explored a double-segmented molecule containing two atomic sections, each with a net spin state and interacting via Heisenberg exchange coupling within molecules and with ferromagnetic electrodes. The effect of thermal energy was explored on the impact of intra-molecular coupling on the MTJMSD Heisenberg model. We performed Monte Carlo simulations(MCS) to study various possibilities in the strong molecule-ferromagnet coupling regime. This research provides insights into the influence of complex molecules on MSD that can be employed in futuristic computers and novel magnetic meta-materials. 

The hysteresis loop investigations of different size magnetic tunnel junction molecular spintronics devices (MTJMSD) have been done by Monte Carlo simulation (MCS). We employed a continuous MCS algorithm to investigate single-molecule magnet SMM’s spin state’s impact as a function of molecular exchange coupling strength. The applied magnetic fields were ramped at a variety of ranges of increments, unfolding physics behind the magnetization nature of each MTJMSD. The magnetic moment changes with applied magnetic fields exhibit the characteristics of devices being studied. The MTJMSDs were studied for ferromagnetic and antiferromagnetic exchange couplings. The magnetic moment saturation, retentivity, coercivity, and permeability are studied. 

Increasing balance confidence in older individuals is important towards improving their quality of life and reducing activity avoidance. Here, we investigated if balance confidence (perceived ability) and balance performance (ability) in older adults were related to one another and would improve after balance training. The relationship of balance confidence in conjunction with balance performance for varied conditions (such as limiting vision, modifying somatosensory cues, and also base of support) was explored. We sought to determine if balance confidence and ability, as well as their relationship, could change after several weeks of training. Twenty-seven healthy participants were trained for several weeks during standing and walking exercises. In addition, seven participants with a higher risk of imbalance leading to falls (survivors of stroke) were also trained. Prior to and after training, balance ability and confidence were assessed via the Balance Error Scoring System (BESS) and Activities Specific Balance Confidence (ABC) Scale, respectively. Both groups showed improvements in balance abilities (i.e., BESS errors significantly decreased after training). Balance confidence was significantly higher in the healthy group than in the stroke group; however, ABC results reflected that balance confidence did not significantly increase after training for each. The correlations between balance ability and balance confidence were explored. Encouragingly, healthy participants displayed a negative correlation between BESS errors and ABC (i.e., enhancements in balance confidence (increases in ABC Scale results) were related to improvements in balance ability (decreases in BESS errors)). For the stroke participants, despite improvements in balance ability, our results showed that there was no relation to balance confidence (i.e., no correlation between BESS errors and ABC) in this group. 

For the rapidly growing aging demographic worldwide, robotic training methods could be impactful towards improving balance critical for everyday life. Here, we investigated the hypothesis that non-bodyweight supportive (nBWS) overground robotic balance training would lead to improvements in balance performance and balance confidence in older adults. Sixteen healthy older participants (69.7 ± 6.7 years old) were trained while donning a harness from a distinctive NaviGAITor robotic system. A control group of 11 healthy participants (68.7 ± 5.0 years old) underwent the same training but without the robotic system. Training included 6 weeks of standing and walking tasks while modifying: (1) sensory information (i.e., with and without vision (eyes-open/closed), with more and fewer support surface cues (hard or foam surfaces)) and (2) base-of-support (wide, tandem and single-leg standing exercises). Prior to and post-training, balance ability and balance confidence were assessed via the balance error scoring system (BESS) and the Activities specific Balance Confidence (ABC) scale, respectively. Encouragingly, results showed that balance ability improved (i.e., BESS errors significantly decreased), particularly in the nBWS group, across nearly all test conditions. This result serves as an indication that robotic training has an impact on improving balance for healthy aging individuals. 

With the massive growth of the aging population worldwide, of utmost importance is reducing falls. Critical to reducing fall risk is one's ability to weight incoming sensory information towards maintaining balance. The purpose of this research was to investigate if simple, targeted sensory training on aging individuals (50 - 80 years old), including twelve healthy and eight individuals with chronic stroke, could improve their balance. Repeated sensory training targeted visual (via eyes-open/closed) and somatosensory inputs (via light touch to the fingertip as well as hard, soft foam, and hard foam support surfaces to the feet) during standing and dynamic base-of-support (BOS) exercises. Study participants underwent six weeks of training. Prior to and post training, standing balance was assessed via a simple, clinical measure: the balance error scoring system (BESS). Following several weeks of training, participants showed significant improvements in BESS errors: healthy participants for small BOS with limited somatosensory information (i.e., tandem and single-leg standing on foam) and participants with stroke in all conditions.Clinical Relevance- This research study demonstrated that simple, accessible exercises, can positively impact balance in the aging population, a pressing need.