Aqueous Zn-Tetrazine Batteries with Cooperative Zn2+/H+ Insertion.

We present the investigation of 1,2,4,5-tetrazine derivatives as low-cost and synthetically modular organic electrode materials in rechargeable aqueous Zn-ion batteries (AZIBs). The substituents at the 3,6-positions of tetrazine were found to be critical for cycling stability. While heteroatom substituents (chloro, methoxy, and pyrazole) lead to the rapid decomposition of electrode materials in the electrolyte, the installation of phenyl groups enhances the cycling stability via π-π stacking. Spectroscopic characterization suggests a cooperative Zn2+ and H+ insertion mechanism. This unique cooperativity of Zn2+ and H+ leads to a steady discharge plateau in contrast to the undesirable sloping voltage profile typically observed in Zn-organic batteries.

Association Between Physical Activity and Physical Function in a Marshallese Population with Type 2 Diabetes.

Physical activity can delay functional decline in people with type 2 diabetes (T2D), but these associations have not been studied within a sample of Native Hawaiian or Pacific Islander adults with T2D. Using data from a randomized control trial in which 218 Marshallese adults with T2D participated in a 10-week diabetes self-management education intervention, this study tested our hypothesis that physical activity would predict physical function when controlling for time and other variables. Levels of physical activity were positively associated with levels of physical function, even after controlling for time and other covariates. These findings provide a more robust understanding of the relationship between physical activity and physical function in a sample of minority adults with T2D. Future studies should further explore levels of physical activity needed to maintain and improve physical function so that culturally appropriate physical activity interventions can be developed.

Multi-scale measurement of stiffness in the developing ferret brain.

Cortical folding is an important process during brain development, and aberrant folding is linked to disorders such as autism and schizophrenia. Changes in cell numbers, size, and morphology have been proposed to exert forces that control the folding process, but these changes may also influence the mechanical properties of developing brain tissue. Currently, the changes in tissue stiffness during brain folding are unknown. Here, we report stiffness in the developing ferret brain across multiple length scales, emphasizing changes in folding cortical tissue. Using rheometry to measure the bulk properties of brain tissue, we found that overall brain stiffness increases with age over the period of cortical folding. Using atomic force microscopy to target the cortical plate, we found that the occipital cortex increases in stiffness as well as stiffness heterogeneity over the course of development and folding. These findings can help to elucidate the mechanics of the cortical folding process by clarifying the concurrent evolution of tissue properties.

Differences in Habitual and Maximal Gait Velocity Across Age Groups: A Cross-Sectional Examination.

Prior work, primarily focusing on habitual gait velocity, has demonstrated a cost while walking when coupled with a cognitive task. The cost of dual-task walking is exacerbated with age and complexity of the cognitive or motor task. However, few studies have examined the dual-task cost associated with maximal gait velocity. Thus, this cross-sectional study examined age-related changes in dual-task (serial subtraction) walking at two velocities. Participants were classified by age: young-old (45-64 years), middle-old (65-79 years), and oldest-old (≥80 years). They completed single- and dual-task walking trials for each velocity: habitual (N = 217) and maximal (N = 194). While no significant Group × Condition interactions existed for habitual or maximal gait velocities, the main effects for both condition and age groups were significant (p < .01). Maximal dual-task cost (p = .01) was significantly greater in the oldest-old group. With age, both dual-task velocities decreased. Maximal dual-task cost was greatest for the oldest-old group.

Matrix obstructions cause multiscale disruption in collective epithelial migration by suppressing leader cell function.

During disease and development, physical changes in extracellular matrix cause jamming, unjamming, and scattering in epithelial migration. However, whether disruptions in matrix topology alter collective cell migration speed and cell-cell coordination remains unclear. We microfabricated substrates with stumps of defined geometry, density, and orientation, which create obstructions for migrating epithelial cells. Here, we show that cells lose their speed and directionality when moving through densely spaced obstructions. Although leader cells are stiffer than follower cells on flat substrates, dense obstructions cause overall cell softening. Through a lattice-based model, we identify cellular protrusions, cell-cell adhesions, and leader-follower communication as key mechanisms for obstruction-sensitive collective cell migration. Our modeling predictions and experimental validations show that cells' obstruction sensitivity requires an optimal balance of cell-cell adhesions and protrusions. Both MDCK (more cohesive) and α-catenin-depleted MCF10A cells were less obstruction sensitive than wild-type MCF10A cells. Together, microscale softening, mesoscale disorder, and macroscale multicellular communication enable epithelial cell populations to sense topological obstructions encountered in challenging environments. Thus, obstruction-sensitivity could define "mechanotype" of cells that collectively migrate yet maintain intercellular communication.

Reciprocal intra- and extra-cellular polarity enables deep mechanosensing through layered matrices.

Adherent cells migrate on layered tissue interfaces to drive morphogenesis, wound healing, and tumor invasion. Although stiffer surfaces are known to enhance cell migration, it remains unclear whether cells sense basal stiff environments buried under softer, fibrous matrix. Using layered collagen-polyacrylamide gel systems, we unveil a migration phenotype driven by cell-matrix polarity. Here, cancer (but not normal) cells with stiff base matrix generate stable protrusions, faster migration, and greater collagen deformation because of "depth mechanosensing" through the top collagen layer. Cancer cell protrusions with front-rear polarity produce polarized collagen stiffening and deformations. Disruption of either extracellular or intracellular polarity via collagen crosslinking, laser ablation, or Arp2/3 inhibition independently abrogates depth-mechanosensitive migration of cancer cells. Our experimental findings, validated by lattice-based energy minimization modeling, present a cell migration mechanism whereby polarized cellular protrusions and contractility are reciprocated by mechanical extracellular polarity, culminating in a cell-type-dependent ability to mechanosense through matrix layers.

Views of in-person and virtual group exercise before and during the pandemic in people with Parkinson disease.

INTRODUCTION: Due to coronavirus disease 2019 (COVID-19), many health/wellness programs transitioned from in-person to virtual. This mixed-methods study aims to explore the perceptions of older adults with Parkinson disease (PD) regarding in-person versus virtual-based Parkinson-specific exercise classes (PDEx). OBJECTIVE: Explore experiences, perceptions, and perceived effect of participating in and transitioning from in-person to virtual PDEx in people with Parkinson disease (PwPD). DESIGN: Cross-sectional mixed-methods design using an online survey and focus groups. SETTING: PwPD who participated in an in-person and virtual PDEx (n = 26) were recruited to participate and completed online surveys and focus groups from their home during the COVID-19 pandemic. PARTICIPANTS: PwPD who participated in an in-person and virtual PDEx and agreed to participate completed an online survey (n = 16; male = 8; mean age = 74 years) and focus groups (n = 9; male = 4; mean age = 75 years). INTERVENTIONS: N/A MAIN OUTCOME MEASURES: Participants completed survey questions and participated in focus groups regarding their perceptions, attitudes, and perceived changes in PD-related symptoms since participating in the PDEx, as well as barriers and facilitators to participating in virtual PDEx. RESULTS: Participants felt PDEx was somewhat to very safe and beneficial. In the computer, comfort, and perceptions survey, participants reported perceived improved mobility (63%), balance (75%), and overall health (63%) since participating the PDEx, whereas some participants reported improved mental health (38%). Participants reported minimal difficulty with accessing virtual PDEx. Most participants stated that they would prefer to participate in a combination of in-person and virtual programming. Focus-group participants emphasized that virtual PDEx provided social and emotional support and improved confidence to perform and maintain an exercise regimen. CONCLUSION: PwPD who transitioned from an in-person to a virtual PDEx felt the program was safe, effective, and improved or prevented declines in their mobility and balance. PwPD who transitioned to a virtual PDEx also reported benefits in non-motor symptoms such as social isolation.

Stronger fertilization effects on aboveground versus belowground plant properties across nine U.S. grasslands.

Increased nutrient inputs due to anthropogenic activity are expected to increase primary productivity across terrestrial ecosystems, but changes in allocation aboveground versus belowground with nutrient addition have different implications for soil carbon (C) storage. Thus, given that roots are major contributors to soil C storage, understanding belowground net primary productivity (BNPP) and biomass responses to changes in nutrient availability is essential to predicting carbon-climate feedbacks in the context of interacting global environmental changes. To address this knowledge gap, we tested whether a decade of nitrogen (N) and phosphorus (P) fertilization consistently influenced aboveground and belowground biomass and productivity at nine grassland sites spanning a wide range of climatic and edaphic conditions in the continental United States. Fertilization effects were strong aboveground, with both N and P addition stimulating aboveground biomass at nearly all sites (by 30% and 36%, respectively, on average). P addition consistently increased root production (by 15% on average), whereas other belowground responses to fertilization were more variable, ranging from positive to negative across sites. Site-specific responses to P were not predicted by the measured covariates. Atmospheric N deposition mediated the effect of N fertilization on root biomass and turnover. Specifically, atmospheric N deposition was positively correlated with root turnover rates, and this relationship was amplified with N addition. Nitrogen addition increased root biomass at sites with low N deposition but decreased it at sites with high N deposition. Overall, these results suggest that the effects of nutrient supply on belowground plant properties are context dependent, particularly with regard to background N supply rates, demonstrating that site conditions must be considered when predicting how grassland ecosystems will respond to increased nutrient loading from anthropogenic activity.

Grassland ecosystem type drives AM fungal diversity and functional guild distribution in North American grasslands.

Nutrient exchange forms the basis of the ancient symbiotic relationship that occurs between most land plants and arbuscular mycorrhizal (AM) fungi. Plants provide carbon (C) to AM fungi and fungi provide the plant with nutrients such as nitrogen (N) and phosphorous (P). Nutrient addition can alter this symbiotic coupling in key ways, such as reducing AM fungal root colonization and changing the AM fungal community composition. However, environmental parameters that differentiate ecosystems and drive plant distribution patterns (e.g., pH, moisture), are also known to impact AM fungal communities. Identifying the relative contribution of environmental factors impacting AM fungal distribution patterns is important for predicting biogeochemical cycling patterns and plant-microbe relationships across ecosystems. To evaluate the relative impacts of local environmental conditions and long-term nutrient addition on AM fungal abundance and composition across grasslands, we studied experimental plots amended for 10 years with N, P, or N and P fertilizer in different grassland ecosystem types, including tallgrass prairie, montane, shortgrass prairie, and desert grasslands. Contrary to our hypothesis, we found ecosystem type, not nutrient treatment, was the main driver of AM fungal root colonization, diversity, and community composition, even when accounting for site-specific nutrient limitations. We identified several important environmental drivers of grassland ecosystem AM fungal distribution patterns, including aridity, mean annual temperature, root moisture, and soil pH. This work provides empirical evidence for niche partitioning strategies of AM fungal functional guilds and emphasizes the importance of long-term, large scale research projects to provide ecologically relevant context to nutrient addition studies.

Personalized practice dosages may improve motor learning in older adults compared to "standard of care" practice dosages: A randomized controlled trial.

Standard dosages of motor practice in clinical physical rehabilitation are insufficient to optimize motor learning, particularly for older patients who often learn at a slower rate than younger patients. Personalized practice dosing (i.e., practicing a task to or beyond one's plateau in performance) may provide a clinically feasible method for determining a dose of practice that is both standardized and individualized, and may improve motor learning. The purpose of this study was to investigate whether personalized practice dosages [practice to plateau (PtP) and overpractice (OVP)] improve retention and transfer of a motor task, compared to low dose [LD] practice that mimics standard clinical dosages. In this pilot randomized controlled trial (NCT02898701, ClinicalTrials.gov), community-dwelling older adults (n = 41, 25 female, mean age 68.9 years) with a range of balance ability performed a standing serial reaction time task in which they stepped to specific targets. Presented stimuli included random sequences and a blinded repeating sequence. Participants were randomly assigned to one of three groups: LD (n = 15, 6 practice trials equaling 144 steps), PtP (n = 14, practice until reaching an estimated personal plateau in performance), or OVP (n = 12, practice 100% more trials after reaching an estimated plateau in performance). Measures of task-specific learning (i.e., faster speed on retention tests) and transfer of learning were performed after 2-4 days of no practice. Learning of the random sequence was greater for the OVP group compared to the LD group (p = 0.020). The OVP (p = 0.004) and PtP (p = 0.010) groups learned the repeated sequence more than the LD group, although the number of practice trials across groups more strongly predicted learning (p = 0.020) than did group assignment (OVP vs. PtP, p = 0.270). No group effect was observed for transfer, although significant transfer was observed in this study as a whole (p < 0.001). Overall, high and personalized dosages of postural training were well-tolerated by older adults, suggesting that this approach is clinically feasible. Practicing well-beyond standard dosages also improved motor learning. Further research should determine the clinical benefit of this personalized approach, and if one of the personalized approaches (PtP vs. OVP) is more beneficial than the other for older patients.

Synthesis of Benzo[b]thiophenes via Electrophilic Sulfur Mediated Cyclization of Alkynylthioanisoles.

A stable dimethyl(thiodimethyl)sulfonium tetrafluoroborate salt was employed for the electrophilic cyclization reaction of o-alkynyl thioanisoles for the synthesis of 2,3-disubstituted benzo[b]thiophenes. The reaction described herein works well with various substituted alkynes in excellent yields, and a valuable thiomethyl group was introduced with ease. The reaction utilizes moderate reaction conditions and ambient temperature while tolerating various functionalities. To elucidate the mechanism, electrophilic addition reactions using the dimethyl(thiodimethyl)sulfonium tetrafluoroborate salt with diphenylacetylene was demonstrated.

Associations between physical activity, sleep, and self-reported health with burnout of medical students, faculty and staff in an academic health center.

Background and objectives: Health behaviors of physical activity and sleep are critical to the prevention of numerous chronic diseases. The health behaviors of healthcare professionals are even more critical, as healthcare providers who practice positive health behaviors are more likely to promote these healthy behaviors in their patients. Aims: To assess the health status and health behaviors of medical students, faculty, and staff in an academic health center in the US, and examine the associations between behaviors, physical and mental health outcomes and burnout. Methods: Students, faculty, residents and staff from a large university medical system completed an online survey between late-September and mid-November 2019. Associations were examined between health behaviors and health status including mental health outcomes with burnout. Results: Participating in any leisure time physical activity and having a Pittsburgh Sleep Quality Index score < 5 were associated with fewer physical health conditions and lower odds of reporting pain at any site (n = 2060; students n = 242, residents n = 32, staff n = 1425, faculty n = 361). Leisure physical activity and fewer sleep symptoms were associated with fewer reported depressive, anxiety and stress-related symptoms. Participating in leisure physical activity and good-quality sleep were associated with lower odds of burnout. Conclusions: The current study found high rates of physical inactivity and poor sleep among medical students, faculty and staff at an academic health center. These health behaviors were associated with poor mental health and high burnout. Programs and policies are needed improve these health behaviors to reduce burnout. Supplementary Information: The online version contains supplementary material available at 10.1007/s11332-022-00902-7.

Associations between physical activity and functional limitations in Native Hawaiian and Pacific Islander middle-aged and older adults in the United States.

OBJECTIVES: Physical activity (PA) can help individuals maintain physical function and independence. The association between PA and functional limitations (FL) has not been explored in the Native Hawaiian and Pacific Islander (NHPI) population. The purpose of this study was to examine relationships between PA and FL among NHPI adults (age ≥ 45 years) living in the United States. DESIGN: Cross-sectional data from the 2014 NHPI-National Health Interview Survey (N = 628) was used to create three constructs of FL based on responses from the Functioning and Disability Survey Module: needing equipment/assistance, having difficulty walking, and having difficulty with performing self-care and other fine motor activities. We used 2-stage least squares regression to examine the relationship between PA and FL of NHPI adults while accounting for the potential endogeneity of PA to FL. RESULTS: Compared to NHPI adults who met the guideline for recommended levels of aerobic and strengthening PA, those who met only the strengthening guideline experienced less difficulty in two FL constructs (use of medical equipment/assistance and difficulty walking). Those who met the aerobic guideline reported even less difficulties in all three FL constructs. NHPI adults who met both the aerobic and strengthening guidelines experienced the least difficulties in all three FL constructs compared to those who met neither PA guidelines. CONCLUSIONS: PA is associated with function in this adult NHPI population. Aerobic guidelines alone may be more beneficial than meeting the strengthening guideline alone; however, meeting both the aerobic and strengthening guidelines is most protective against FL.

Soil carbon stocks in temperate grasslands differ strongly across sites but are insensitive to decade-long fertilization.

Enhancing soil carbon (C) storage has the potential to offset human-caused increases in atmospheric CO2 . Rising CO2 has occurred concurrently with increasing supply rates of biologically limiting nutrients such as nitrogen (N) and phosphorus (P). However, it is unclear how increased supplies of N and P will alter soil C sequestration, particularly in grasslands, which make up nearly a third of non-agricultural land worldwide. Here, we leverage a globally distributed nutrient addition experiment (the Nutrient Network) to examine how a decade of N and P fertilization (alone and in combination) influenced soil C and N stocks at nine grassland sites spanning the continental United States. We measured changes in bulk soil C and N stocks and in three soil C fractions (light and heavy particulate organic matter, and mineral-associated organic matter fractions). Nutrient amendment had variable effects on soil C and N pools that ranged from strongly positive to strongly negative, while soil C and N pool sizes varied by more than an order of magnitude across sites. Piecewise SEM clarified that small increases in plant C inputs with fertilization did not translate to greater soil C storage. Nevertheless, peak season aboveground plant biomass (but not root biomass or production) was strongly positively related to soil C storage at seven of the nine sites, and across all nine sites, soil C covaried with moisture index and soil mineralogy, regardless of fertilization. Overall, we show that site factors such as moisture index, plant productivity, soil texture, and mineralogy were key predictors of cross-site soil C, while nutrient amendment had weaker and site-specific effects on C sequestration. This suggests that prioritizing the protection of highly productive temperate grasslands is critical for reducing future greenhouse gas losses arising from land use change.

How Common Is the Exponential Decay Pattern of Motor Skill Acquisition? A Brief Investigation.

Motor performance is classically described as improving nonlinearly with practice, demonstrating rapid improvements early in practice with stabilization later, which is commonly modeled by exponential decay functions. However, retrospective analyses of our previously collected data challenge this theoretical model of motor skill acquisition, suggesting that a majority of individual learners actually demonstrate patterns of motor improvement different from this classical model. A convenience sample of young adults, older adults, and people with Parkinson disease trained on the same functional upper-extremity task. When fitting three-parameter exponential decay functions to individual participant data, the authors found that only 13.3% of young adults, 40.9% of older adults, and 66.7% of adults with Parkinson disease demonstrated this "classical" skill acquisition pattern. Thus, the three-parameter exponential decay pattern may not well-represent individuals' skill acquisition of complex motor tasks; instead, more individualized analysis methods may be warranted for advancing a theoretical understanding of motor skill acquisition.

The feasibility and efficacy of a serial reaction time task that measures motor learning of anticipatory stepping.

BACKGROUND: Motor learning has been investigated using various paradigms, including serial reaction time tasks (SRTT) that examine upper extremity reaching and pointing while seated. Few studies have used a stepping SRTT, which could offer additional insights into motor learning involving postural demands. For a task to measure motor learning, naïve participants must demonstrate a) improved performance with task practice, and b) a dose-response relationship to learning the task. RESEARCH QUESTION: Is a stepping SRTT feasible and efficacious for measuring motor learning? METHODS: In this prospective study, 20 participants stood on an instrumented mat and were presented with stimuli on a computer screen. They stepped to the corresponding positions on the mat as quickly as possible. Presented stimuli included random sequences and a blinded imbedded repeating sequence. Three days after completing the randomly assigned practice dose [high dose group (n = 10) performed 4320 steps; low dose group (n = 10) performed 144 steps], a retention test of 72 steps was performed. Feasibility was measured as the proportion of participants who completed the assigned practice dose without adverse events. Efficacy was measured as within-group performance improvement on the random sequences and on the repeating sequence (paired t-tests), as well as a dose-response relationship to learning both types of sequences (independent t-tests). RESULTS: All participants (mean age 26.8 years) completed all practice sessions without adverse events, indicating feasibility. High dose practice resulted in performance improvement while low dose did not; a dose-response relationship was found, with high dose practice resulting in greater learning of the task than low dose practice, indicating efficacy. SIGNIFICANCE: This stepping SRTT is a feasible and efficacious way to measure motor learning, which could provide critical insights into anticipatory stepping, postural control, and fall risk. Future research is needed to determine feasibility, efficacy, and optimal practice dosages for older and impaired populations.

Description of Variation in Age of Onset of Functional Limitations of Native Hawaiian and Pacific Islanders Compared to Other Racial and Ethnic Groups.

(1) Background: The purpose of this exploratory study was to describe variation in age of onset of functional limitations of Native Hawaiian and Pacific Islanders (NHPI) compared to other racial and ethnic groups. (2) Methods: Adults age 45 years and older who responded to the Functioning and Disability module within the 2014 National Health Interview Survey (NHIS) were included (n = 628 NHPI; 7122 non-Hispanic Whites; 1418 Blacks; 470 Asians; and 1216 Hispanic adults). The NHIS Functioning and Disability module included 13 items, which we organized into three domains of functional limitations using factor analysis: Mobility, Gross Motor Skills, and Fine Motor Skills. Responses were summed within each domain. (3) Results: After adjusting for age and sex, we found that racial/ethnic minority groups, with the exception of Asians, experience more functional limitations than Whites. Results further indicate that NHPI adults experienced an earlier surge in all three domains of functional limitations compared to other racial/ethnic groups. (4) Conclusions: These findings are novel and provide additional evidence to the existence of disparities in functional health outcomes across racial/ethnic groups. Future studies are needed to develop targeted and culturally tailored interventions for those most in need.

Altered plant carbon partitioning enhanced forest ecosystem carbon storage after 25 years of nitrogen additions.

Decades of atmospheric nitrogen (N) deposition in the northeastern USA have enhanced this globally important forest carbon (C) sink by relieving N limitation. While many N fertilization experiments found increased forest C storage, the mechanisms driving this response at the ecosystem scale remain uncertain. Following the optimal allocation theory, augmented N availability may reduce belowground C investment by trees to roots and soil symbionts. To test this prediction and its implications on soil biogeochemistry, we constructed C and N budgets for a long-term, whole-watershed N fertilization study at the Fernow Experimental Forest, WV, USA. Nitrogen fertilization increased C storage by shifting C partitioning away from belowground components and towards aboveground woody biomass production. Fertilization also reduced the C cost of N acquisition, allowing for greater C sequestration in vegetation. Despite equal fine litter inputs, the C and N stocks and C : N ratio of the upper mineral soil were greater in the fertilized watershed, likely due to reduced decomposition of plant litter. By combining aboveground and belowground data at the watershed scale, this study demonstrates how plant C allocation responses to N additions may result in greater C storage in both vegetation and soil.

Differences in microbial community response to nitrogen fertilization result in unique enzyme shifts between arbuscular and ectomycorrhizal-dominated soils.

While the effect of nitrogen (N) deposition on belowground carbon (C) cycling varies, emerging evidence shows that forest soils dominated by trees that associate with ectomycorrhizal fungi (ECM) store more C than soils dominated by trees that associate with arbuscular mycorrhizae (AM) with increasing N deposition. We hypothesized that this is due to unique nutrient cycling responses to N between AM and ECM-dominated soils. ECM trees primarily obtain N through fungal mining of soil organic matter subsidized by root-C. As such, we expected the largest N-induced responses of C and N cycling to occur in ECM rhizospheres and be driven by fungi. Conversely, as AM trees rely on bacterial scavengers in bulk soils to cycle N, we predicted the largest AM responses to be driven by shifts in bacteria and occur in bulk soils. To test this hypothesis, we measured microbial community composition, metatranscriptome profiles, and extracellular enzyme activity in bulk, rhizosphere, and organic horizon (OH) soils in AM and ECM-dominated soils at Bear Brook Watershed in Maine, USA. After 27 years of N fertilization, fungal community composition shifted across ECM soils, but bacterial communities shifted across AM soils. These shifts were mirrored by enhanced C relative to N mining enzyme activities in both mycorrhizal types, but this occurred in different soil fractions. In ECM stands these shifts occurred in rhizosphere soils, but in AM stands they occurred in bulk soils. Additionally, ECM OH soils exhibited the opposite response with declines in C relative to N mining. As rhizosphere soils account for only a small portion of total soil volume relative to bulk soils, coupled with declines in C to N enzyme activity in ECM OH soils, we posit that this may partly explain why ECM soils store more C than AM soils as N inputs increase.

Redox-active zinc thiolates for low-cost aqueous rechargeable Zn-ion batteries.

Aqueous zinc-ion batteries (AZIBs) are promising candidates for large-scale electrical energy storage due to the inexpensive, safe, and non-toxic nature of zinc. One key area that requires further development is electrode materials that store Zn2+ ions with high reversibility and fast kinetics. To determine the viability of low-cost organosulfur compounds as OEMs for AZIBs, we investigate how structural modification affects electrochemical performance in Zn-thiolate complexes 1 and 2. Remarkably, modification of one thiolate in 1 to sulfide in 2 reduces the voltage hysteresis from 1.04 V to 0.15 V. While 1 exhibits negligible specific capacity due to the formation of insulating DMcT polymers, 2 delivers a capacity of 107 mA h g-1 with a primary discharge plateau at 1.1 V vs. Zn2+/Zn. Spectroscopic studies of 2 suggest a Zn2+ and H+ co-insertion mechanism with Zn2+ as the predominant charge carrier. Capacity fading in Zn-2 cells likely results from the formation of (i) soluble H+ insertion products and (ii) non-redox-active side products. Increasing electrolyte concentration and using a Nafion membrane significantly enhances the stability of 2 by suppressing H+ insertion. Our findings provide insight into the molecular design strategies to reduce the polarization potential and improve the cycling stability of the thiolate/disulfide redox couple in aqueous battery systems.