Research Experience and Training Coordination Core (RETCC)

2024 Jan 18

RETCC Career Hour

12:00pm

Location: 

Via Zoom

Join RETCC Director Susan Korrick in a conversation with Donna Vorhees, ScD and Jessica Shoaff, PhD as they talk about their inspiring career trajectories.  

Panelists:

Jessica Shoaff is Associate Director of Epidemiology at Biogen, Cambridge, a pharmaceutical company that develops and delivers therapies for people living with serious neurological and neurodegenerative diseases. Dr. Shoaff has a B.S. in Neuroscience from Dickinson College, an MPH from Boston University School of Public Health, and a Ph.D. in Epidemiology from Brown University. She did postdoctoral research at Harvard Medical School and the Harvard TH Chan School of Public Health and has worked in biotech and pharmaceuticals since 2020.

Donna Vorhees is CEO and Vice President of HEI Energy, Boston, a nonprofit affiliate of the Health Effects Institute (HEI). HEI Energy is an independent research organization providing impartial science about potential human exposure and health effects associated with onshore development of oil and natural gas from shale and other unconventional resources (UOGD) in the US. Dr. Vorhees leads HEI Energy’s work in providing information about potential human exposures and health effects associated with unconventional oil and gas development and how they might be prevented or minimized. She received her Sc.M. and Sc.D. in Environmental Health from the Harvard School of Public Health.... Read more about RETCC Career Hour

Xinye Qiu, Andrea L Robert, Kaleigh McAlaine, Luwei Quan, Joseph Mangano, and Marc G Weisskopf. 2023. “Early-life participation in cognitively stimulating activities and risk of depression and anxiety in late life.” Psychol Med, Pp. 1-9.Abstract

BACKGROUND: Early-life stressful experiences are associated with increased risk of adverse psychological outcomes in later life. However, much less is known about associations between early-life positive experiences, such as participation in cognitively stimulating activities, and late-life mental health. We investigated whether greater engagement in cognitively stimulating activities in early life is associated with lower risk of depression and anxiety in late life.

METHODS: We surveyed former participants of the St. Louis Baby Tooth study, between 22 June 2021 and 25 March 2022 to collect information on participants' current depression/anxiety symptoms and their early-life activities ( = 2187 responded). A composite activity score was created to represent the early-life activity level by averaging the frequency of self-reported participation in common cognitively stimulating activities in participants' early life (age 6, 12, 18), each rated on a 1 (least frequent) to 5 (most frequent) point scale. Depression/anxiety symptoms were measured by Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder Screener (GAD-7). We used logistic regressions to estimate odds ratios (OR) and 95% confidence intervals (CI) of outcome risk associated with frequency of early-life activity.

RESULTS: Each one-point increase in the early-life composite cognitive activity score was associated with an OR of 0.54 (95% CI 0.38-0.77) for late-life depression and an OR of 0.94 (95% CI 0.61-1.43) for late-life anxiety, adjusting for age, sex, race, parental education, childhood family structure, and socioeconomic status.

CONCLUSIONS: More frequent participation in cognitively stimulating activities during early life was associated with reduced risk of late-life depression.

2023 Oct 26

Trainee Work in Progress - Justin Farmer

12:00pm

Location: 

Via Zoom

Justin FarmerMEMCARE-SRC Trainee Work-in-Progress and RETCC meeting
Neighborhood Resources and Later Life Cognitive Function
Justin Farmer
PhD Student in Environmental Epidemiology, Harvard TH Chan School of Public Health

All MEMCARE-SRC Investigators and Trainees are encouraged to attend.

2023 Sep 28

Communicating Your Science to Non-Experts

12:00pm

Location: 

Via Zoom

MEMCARE-SRC RETCC Seminar 

Special Guest: Amanda Yarnell
Senior Director, Center for Health Communication, and Instructor, Department of Social and Behavioral Sciences, Harvard TH Chan School of Public Health

Via zoom - Details to follow.

All MEMCARE-SRC Investigators and Trainees are welcome.

 

Michael Leung, Sebastian T Rowland, Brent A Coull, Anna M Modest, Michele R Hacker, Joel Schwartz, Marianthi-Anna Kioumourtzoglou, Marc G Weisskopf, and Ander Wilson. 2023. “Bias Amplification and Variance Inflation in Distributed Lag Models Using Low-Spatial-Resolution Data.” Am J Epidemiol, 192, 4, Pp. 644-657. Publisher's VersionAbstract

Distributed lag models (DLMs) are often used to estimate lagged associations and identify critical exposure windows. In a simulation study of prenatal nitrogen dioxide (NO2) exposure and birth weight, we demonstrate that bias amplification and variance inflation can manifest under certain combinations of DLM estimation approaches and time-trend adjustment methods when using low-spatial-resolution exposures with extended lags. Our simulations showed that when using high-spatial-resolution exposure data, any time-trend adjustment method produced low bias and nominal coverage for the distributed lag estimator. When using either low- or no-spatial-resolution exposures, bias due to time trends was amplified for all adjustment methods. Variance inflation was higher in low- or no-spatial-resolution DLMs when using a long-term spline to adjust for seasonality and long-term trends due to concurvity between a distributed lag function and secular function of time. NO2-birth weight analyses in a Massachusetts-based cohort showed that associations were negative for exposures experienced in gestational weeks 15-30 when using high-spatial-resolution DLMs; however, associations were null and positive for DLMs with low- and no-spatial-resolution exposures, respectively, which is likely due to bias amplification. DLM analyses should jointly consider the spatial resolution of exposure data and the parameterizations of the time trend adjustment and lag constraints.

Holly E Rudel and Julie B Zimmerman. 2023. “Elucidating the Role of Capping Agents in Facet-Dependent Adsorption Performance of Hematite Nanostructures.” ACS Appl Mater Interfaces, 15, 29, Pp. 34829-34837.Abstract

Organic capping agents are a ubiquitous and crucial part of preparing reproducible and homogeneous batches of nanomaterials, particularly nanocrystals with well-defined facets. Despite studies reporting surface ligands (e.g., capping agents) having a non-negligible role in catalytic behavior, their impact is less understood in contaminant adsorption, an important consideration given their potential to obfuscate facet-dependent trends in performance. To ascribe observed behaviors to the facet or the ligand, this report evaluates the impact of poly(-vinyl-2-pyrrolidone) (PVP), a commonly utilized capping agent, on the adsorption performance of nanohematite particles of varying prevailing facet in the removal of selenite (Se(IV)) as a model system. The PVP capping agent reduces the available surface area for contaminant binding, thus resulting in a reduction in overall Se(IV) adsorbed. However, accounting for the effects of surface area, {012}-faceted nanohematite demonstrates a significantly higher sorption capacity for Se(IV) compared with that of {001}-faceted nanohematite. Notably, chemical treatment is minimally effective in removing strongly bound PVP, indicating that complete removal of surface ligands remains challenging.

Lauren N Pincus, Holly E Rudel, Predrag V Petrović, Srishti Gupta, Paul Westerhoff, Christopher L Muhich, and Julie B Zimmerman. 2020. “Exploring the Mechanisms of Selectivity for Environmentally Significant Oxo-Anion Removal during Water Treatment: A Review of Common Competing Oxo-Anions and Tools for Quantifying Selective Adsorption.” Environ Sci Technol, 54, 16, Pp. 9769-9790.Abstract

Development of novel adsorbents often neglects the competitive adsorption between co-occurring oxo-anions, overestimating realistic pollutant removal potentials, and overlooking the need to improve selectivity of materials. This critical review focuses on adsorptive competition between commonly co-occurring oxo-anions in water and mechanistic approaches for the design and development of selective adsorbents. Six "target" oxo-anion pollutants (arsenate, arsenite, selenate, selenite, chromate, and perchlorate) were selected for study. Five "competing" co-occurring oxo-anions (phosphate, sulfate, bicarbonate, silicate, and nitrate) were selected due to their potential to compete with target oxo-anions for sorption sites resulting in decreased removal of the target oxo-anions. First, a comprehensive review of competition between target and competitor oxo-anions to sorb on commonly used, nonselective, metal (hydr)oxide materials is presented, and the strength of competition between each target and competitive oxo-anion pair is classified. This is followed by a critical discussion of the different equations and models used to quantify selectivity. Next, four mechanisms that have been successfully utilized in the development of selective adsorbents are reviewed: variation in surface complexation, Lewis acid/base hardness, steric hindrance, and electrostatic interactions. For each mechanism, the oxo-anions, both target and competitors, are ranked in terms of adsorptive attraction and technologies that exploit this mechanism are reviewed. Third, given the significant effort to evaluate these systems empirically, the potential to use computational quantum techniques, such as density functional theory (DFT), for modeling and prediction is explored. Finally, areas within the field of selective adsorption requiring further research are detailed with guidance on priorities for screening and defining selective adsorbents.

Mona Q Dai, Benjamin M Geyman, Xindi C Hu, Colin P Thackray, and Elsie M Sunderland. 2023. “Sociodemographic Disparities in Mercury Exposure from United States Coal-Fired Power Plants.” Environ Sci Technol Lett, 10, 7, Pp. 589-595. Publisher's VersionAbstract

Hazardous air pollutants emitted by United States (U.S) coal-fired power plants have been controlled by the Mercury and Air Toxics Standards (MATS) since 2012. Sociodemographic disparities in traditional air pollutant exposures from U.S. power plants are known to occur but have not been evaluated for mercury (Hg), a neurotoxicant that bioaccumulates in food webs. Atmospheric Hg deposition from domestic power plants decreased by 91% across the contiguous U.S. from 6.4 Mg in 2010 to 0.55 Mg in 2020. Prior to MATS, populations living within 5 km of power plants ( = 507) included greater proportions of frequent fish consumers, individuals with low annual income and less than a high school education, and limited English-proficiency households compared to the US general population. These results reinforce a lack of distributional justice in plant siting found in prior work. Significantly greater proportions of low-income individuals lived within 5 km of active facilities in 2020 ( = 277) compared to plants that retired after 2010, suggesting that socioeconomic status may have played a role in retirement. Despite large deposition declines, an end-member scenario for remaining exposures from the largest active power plants for individuals consuming self-caught fish suggests they could still exceed the U.S. Environmental Protection Agency reference dose for methylmercury.

Zunwei Chen, Zhi Qiao, Charlotte R Wirth, Hae-Ryung Park, and Quan Lu. 12/2023. “Arrestin domain-containing protein 1-mediated microvesicles (ARMMs) protect against cadmium-induced neurotoxicity.” Extracellular Vesicle, 2, Pp. 100027. Publisher's VersionAbstract
Exposure to environmental heavy metals such as cadmium (Cd) is often linked to neurotoxicity but the underlying mechanisms remain poorly understood. Here we show that Arrestin domain-containing protein 1 (ARRDC1)-mediated microvesicles (ARMMs)–an important class of extracellular vesicles (EVs) whose biogenesis occurs at the plasma membrane–protect against Cd-induced neurotoxicity. Cd increased the production of EVs, including ARMMs, in a human neural progenitor cell line, ReNcell CX (ReN) cells. ReN cells that lack ARMMs production as a result of CRISPR-mediated ARRDC1 knockout were more susceptible to Cd toxicity as evidenced by increased LDH production as well as elevated level of oxidative stress markers. Importantly, adding ARMMs back to the ARRDC1-knockout ReN cells significantly reduced Cd-induced toxicity. Consistent with this finding, proteomics data showed that anti-oxidative stress proteins are enriched in ARMMs secreted from ReN cells. Together our study reveals a novel protective role of ARMMs in Cd neurotoxicity and suggests that ARMMs may be used therapeutically to reduce neurotoxicity caused by exposure to Cd and potentially other metal toxicants.
Alireza Farsad, Ken Niimi, Mahmut Selim Ersan, Jose Ricardo Gonzalez-Rodriguez, Kiril D Hristovski, and Paul Westerhoff. 2023. “Mechanistic Study of Arsenate Adsorption onto Different Amorphous Grades of Titanium (Hydr)Oxides Impregnated into a Point-of-Use Activated Carbon Block.” ACS ES&T EngineeringACS ES&T Engineering, 3, 7, Pp. 989 - 1000. Publisher's VersionAbstract
Millions of households still rely on drinking water from private wells or municipal systems with arsenic levels approaching or exceeding regulatory limits. Arsenic is a potent carcinogen, and there is no safe level of it in drinking water. Point-of-use (POU) treatment systems are a promising option to mitigate arsenic exposure. However, the most commonly used POU technology, an activated carbon block filter, is ineffective at removing arsenic. Our study aimed to explore the potential of impregnating carbon blocks with amorphous titanium (hydr)oxide (THO) to improve arsenic removal without introducing titanium (Ti) into the treated water. Four synthesis methods achieved 8–16 wt % Ti-loading within the carbon block with a 58–97% amorphous THO content. The THO-modified carbon block could adsorb both oxidation states of arsenic (arsenate and arsenite) in batch or column tests. Modified carbon block with higher Ti and amorphous content always led to better arsenate removal, achieving arsenic loadings up to 31 mg As/mg Ti after 70,000 bed volumes in continuous-flow tests. Impregnating carbon block with amorphous THO consistently outperformed impregnation using crystalline TiO2. The best-performing system (TTIP-EtOH carbon block) was an amorphous THO derived using titanium isopropoxide, ethanol, and acetic acid via the sol–gel technique, aged at 80 °C for 18 h and dried overnight at 60 °C. Comparable pore-size distribution and surface area of the impregnated carbon blocks suggested that chemical properties play a more crucial role than physical and textural properties in removing arsenate via the amorphous Ti-impregnated carbon block. Freundlich isotherms indicated energetically favorable adsorption for amorphous chemically synthesized adsorbents. The mass transport coefficients for the amorphous TTIP-EtOH carbon block were fitted using a pore-surface diffusion model, resulting in Dsurface = 3.1 × 10–12 and Dpore = 3.2 × 10–6 cm2/s. Impregnating the carbon block with THO enabled effective arsenic removal from water without adversely affecting the pressure drop across the unit or the carbon block’s ability to remove polar organic chemical pollutants efficiently.Millions of households still rely on drinking water from private wells or municipal systems with arsenic levels approaching or exceeding regulatory limits. Arsenic is a potent carcinogen, and there is no safe level of it in drinking water. Point-of-use (POU) treatment systems are a promising option to mitigate arsenic exposure. However, the most commonly used POU technology, an activated carbon block filter, is ineffective at removing arsenic. Our study aimed to explore the potential of impregnating carbon blocks with amorphous titanium (hydr)oxide (THO) to improve arsenic removal without introducing titanium (Ti) into the treated water. Four synthesis methods achieved 8–16 wt % Ti-loading within the carbon block with a 58–97% amorphous THO content. The THO-modified carbon block could adsorb both oxidation states of arsenic (arsenate and arsenite) in batch or column tests. Modified carbon block with higher Ti and amorphous content always led to better arsenate removal, achieving arsenic loadings up to 31 mg As/mg Ti after 70,000 bed volumes in continuous-flow tests. Impregnating carbon block with amorphous THO consistently outperformed impregnation using crystalline TiO2. The best-performing system (TTIP-EtOH carbon block) was an amorphous THO derived using titanium isopropoxide, ethanol, and acetic acid via the sol–gel technique, aged at 80 °C for 18 h and dried overnight at 60 °C. Comparable pore-size distribution and surface area of the impregnated carbon blocks suggested that chemical properties play a more crucial role than physical and textural properties in removing arsenate via the amorphous Ti-impregnated carbon block. Freundlich isotherms indicated energetically favorable adsorption for amorphous chemically synthesized adsorbents. The mass transport coefficients for the amorphous TTIP-EtOH carbon block were fitted using a pore-surface diffusion model, resulting in Dsurface = 3.1 × 10–12 and Dpore = 3.2 × 10–6 cm2/s. Impregnating the carbon block with THO enabled effective arsenic removal from water without adversely affecting the pressure drop across the unit or the carbon block’s ability to remove polar organic chemical pollutants efficiently.

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