Novel and complementary treatment approaches in attention-deficit/hyperactivity disorder.

PURPOSE OF REVIEW: To provide an updated review of novel and complementary treatment approaches for children and adolescents with attention-deficit/hyperactivity disorder. RECENT FINDINGS: The evidence for complementary attention-deficit/hyperactivity disorder treatments is often promising, but limited to small, unblinded studies. Recent evidence from larger, more rigorous studies reveals that most of these treatments have modest efficacy. Omega-3 polyunsaturated fatty acids, saffron, broad spectrum micronutrients, and physical exercise have potential benefits that seem to outweigh known risks. However, neurofeedback, cognitive training, and trigeminal nerve stimulation need further research to determine whether specific sub-groups of children/adolescents with attention-deficit/hyperactivity disorder would benefit long-term with their associated tolerable risks. SUMMARY: There is not sufficient evidence for complementary treatments to be recommended as substitutes for first-line pharmacological and psychosocial treatment options. Nonetheless, some adjuvant therapies to currently recommended attention-deficit/hyperactivity disorder treatments can be safe. Physicians should be familiar with existing and emerging complementary treatments to help guide families.

Prediction of Vacuum Ultraviolet/Ultraviolet Gas-Phase Absorption Spectra Using Molecular Feature Representations and Machine Learning.

Ultraviolet (UV) absorption spectroscopy is a widely used tool for quantitative and qualitative analyses of chemical compounds. In the gas phase, vacuum UV (VUV) and UV absorption spectra are specific and diagnostic for many small molecules. An accurate prediction of VUV/UV absorption spectra can aid the characterization of new or unknown molecules in areas such as fuels, forensics, and pharmaceutical research. An alternative to quantum chemical spectral prediction is the use of artificial intelligence. Here, different molecular feature representation techniques were used and developed to encode chemical structures for testing three machine learning models to predict gas-phase VUV/UV absorption spectra. Structure data files (.sdf) and VUV/UV absorption spectra for 1397 volatile and semivolatile chemical compounds were used to train and test the models. New molecular features (termed ABOCH) were introduced to better capture pi-bonding, aromaticity, and halogenation. The incorporation of these new features benefited spectral prediction and demonstrated superior performance compared to computationally intensive molecular-based deep learning methods. Of the machine learning methods, the use of a Random Forest regressor returned the best accuracy score with the shortest training time. The developed machine learning prediction model also outperformed spectral predictions based on the time-dependent density functional theory.

VAL genes regulate vegetative phase change via miR156-dependent and independent mechanisms.

How organisms control when to transition between different stages of development is a key question in biology. In plants, epigenetic silencing by Polycomb repressive complex 1 (PRC1) and PRC2 plays a crucial role in promoting developmental transitions, including from juvenile-to-adult phases of vegetative growth. PRC1/2 are known to repress the master regulator of vegetative phase change, miR156, leading to the transition to adult growth, but how this process is regulated temporally is unknown. Here we investigate whether transcription factors in the VIVIPAROUS/ABI3-LIKE (VAL) gene family provide the temporal signal for the epigenetic repression of miR156. Exploiting a novel val1 allele, we found that VAL1 and VAL2 redundantly regulate vegetative phase change by controlling the overall level, rather than temporal dynamics, of miR156 expression. Furthermore, we discovered that VAL1 and VAL2 also act independently of miR156 to control this important developmental transition. In combination, our results highlight the complexity of temporal regulation in plants.

Ambipolar Thickness-Dependent Thermoelectric Measurements of WSe2.

Thermoelectric materials can harvest electrical energy from temperature gradients, and could play a role as power supplies for sensors and other devices. Here, we characterize fundamental in-plane electrical and thermoelectric properties of layered WSe2 over a range of thicknesses, from 10 to 96 nm, between 300 and 400 K. The devices are electrostatically gated with an ion gel, enabling us to probe both electron and hole regimes over a large range of carrier densities. We extract the highest n- and p-type Seebeck coefficients for thin-film WSe2, -500 and 950 µV/K respectively, reported to date at room temperature. We also emphasize the importance of low substrate thermal conductivity on such lateral thermoelectric measurements, improving this platform for future studies on other nanomaterials.

Utilization and Patient-Reported Outcomes of Direct-to-Consumer Telemedicine During the First 6 Weeks of the COVID-19 Pandemic in the Largest Pediatric Ambulatory Network in New York State.

Objective: We aimed to (1) describe telemedicine utilization and usability during the first 6 weeks of the pandemic and (2) determine if usability varied by individual- or visit-level characteristics. Methods: We conducted a retrospective cohort study of ambulatory pediatric telemedicine visits occurring between March 10, 2020, and April 18, 2020, across a large academic health system. We performed manual chart review to assess individual- and visit-level characteristics and invited caregivers to respond to an adapted Telehealth Usability Questionnaire (TUQ). We used multiple logistic regression to determine predictors of high usability. Results: There were 3,197 ambulatory pediatric telemedicine visits, representing 2,967 unique patients. Patients were racially/ethnically diverse (42.5% non-Hispanic White) and primarily English-speaking (89.2%). Surveys were completed by 441 (17%) of those invited. Every item of the TUQ had agreement or strong agreement from the majority of respondents. Compared with non-Hispanic White, non-Hispanic Asian identity was associated with lower usability in three domains and overall, and non-Hispanic Black identity was associated with higher satisfaction and future use. As compared with caregivers of infants younger than 1 year, caregivers of older patients reported lower usability in the three domains. Conclusions: Telemedicine was successfully implemented across 18 ambulatory pediatric specialties in the largest health system in New York State at the onset of COVID-19, and caregivers found it usable and acceptable. Usability scores did not vary by visit-level characteristics but did vary by race/ethnicity and age. Further research is necessary to identify modifiable drivers of the patient experience, particularly in non-Hispanic Asian communities and older adolescents.

ALTERED MERISTEM PROGRAM1 regulates leaf identity independently of miR156-mediated translational repression.

In Arabidopsis, loss of the carboxypeptidase ALTERED MERISTEM PROGRAM1 (AMP1) produces an increase in the rate of leaf initiation, an enlarged shoot apical meristem and an increase in the number of juvenile leaves. This phenotype is also observed in plants with reduced levels of miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, suggesting that AMP1 might promote SPL activity. However, we found that the amp1 mutant phenotype is only partially corrected by elevated SPL gene expression, and that amp1 has no significant effect on SPL transcript levels, or on the level or the activity of miR156. Although AMP1 has been reported to promote miRNA-mediated translational repression, amp1 did not prevent the translational repression of the miR156 target SPL9 or the miR159 target MYB33. These results suggest that AMP1 regulates vegetative phase change downstream of, or in parallel to, the miR156/SPL pathway, and that it is not universally required for miRNA-mediated translational repression.

Depth importance in precision medicine (DIPM): a tree- and forest-based method for right-censored survival outcomes.

Many clinical trials have been conducted to compare right-censored survival outcomes between interventions. Such comparisons are typically made on the basis of the entire group receiving one intervention versus the others. In order to identify subgroups for which the preferential treatment may differ from the overall group, we propose the depth importance in precision medicine (DIPM) method for such data within the precision medicine framework. The approach first modifies the split criteria of the traditional classification tree to fit the precision medicine setting. Then, a random forest of trees is constructed at each node. The forest is used to calculate depth variable importance scores for each candidate split variable. The variable with the highest score is identified as the best variable to split the node. The importance score is a flexible and simply constructed measure that makes use of the observation that more important variables tend to be selected closer to the root nodes of trees. The DIPM method is primarily designed for the analysis of clinical data with two treatment groups. We also present the extension to the case of more than two treatment groups. We use simulation studies to demonstrate the accuracy of our method and provide the results of applications to two real-world data sets. In the case of one data set, the DIPM method outperforms an existing method, and a primary motivation of this article is the ability of the DIPM method to address the shortcomings of this existing method. Altogether, the DIPM method yields promising results that demonstrate its capacity to guide personalized treatment decisions in cases with right-censored survival outcomes.

Nordic dietary patterns and cardiometabolic outcomes: a systematic review and meta-analysis of prospective cohort studies and randomised controlled trials.

AIMS/HYPOTHESIS: Nordic dietary patterns that are high in healthy traditional Nordic foods may have a role in the prevention and management of diabetes. To inform the update of the EASD clinical practice guidelines for nutrition therapy, we conducted a systematic review and meta-analysis of Nordic dietary patterns and cardiometabolic outcomes. METHODS: We searched MEDLINE, EMBASE and The Cochrane Library from inception to 9 March 2021. We included prospective cohort studies and RCTs with a follow-up of ≥1 year and ≥3 weeks, respectively. Two independent reviewers extracted relevant data and assessed the risk of bias (Newcastle-Ottawa Scale and Cochrane risk of bias tool). The primary outcome was total CVD incidence in the prospective cohort studies and LDL-cholesterol in the RCTs. Secondary outcomes in the prospective cohort studies were CVD mortality, CHD incidence and mortality, stroke incidence and mortality, and type 2 diabetes incidence; in the RCTs, secondary outcomes were other established lipid targets (non-HDL-cholesterol, apolipoprotein B, HDL-cholesterol, triglycerides), markers of glycaemic control (HbA1c, fasting glucose, fasting insulin), adiposity (body weight, BMI, waist circumference) and inflammation (C-reactive protein), and blood pressure (systolic and diastolic blood pressure). The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of the evidence. RESULTS: We included 15 unique prospective cohort studies (n=1,057,176, with 41,708 cardiovascular events and 13,121 diabetes cases) of people with diabetes for the assessment of cardiovascular outcomes or people without diabetes for the assessment of diabetes incidence, and six RCTs (n=717) in people with one or more risk factor for diabetes. In the prospective cohort studies, higher adherence to Nordic dietary patterns was associated with 'small important' reductions in the primary outcome, total CVD incidence (RR for highest vs lowest adherence: 0.93 [95% CI 0.88, 0.99], p=0.01; substantial heterogeneity: I2=88%, pQ<0.001), and similar or greater reductions in the secondary outcomes of CVD mortality and incidence of CHD, stroke and type 2 diabetes (p<0.05). Inverse dose-response gradients were seen for total CVD incidence, CVD mortality and incidence of CHD, stroke and type 2 diabetes (p<0.05). No studies assessed CHD or stroke mortality. In the RCTs, there were small important reductions in LDL-cholesterol (mean difference [MD] -0.26 mmol/l [95% CI -0.52, -0.00], pMD=0.05; substantial heterogeneity: I2=89%, pQ<0.01), and 'small important' or greater reductions in the secondary outcomes of non-HDL-cholesterol, apolipoprotein B, insulin, body weight, BMI and systolic blood pressure (p<0.05). For the other outcomes there were 'trivial' reductions or no effect. The certainty of the evidence was low for total CVD incidence and LDL-cholesterol; moderate to high for CVD mortality, established lipid targets, adiposity markers, glycaemic control, blood pressure and inflammation; and low for all other outcomes, with evidence being downgraded mainly because of imprecision and inconsistency. CONCLUSIONS/INTERPRETATION: Adherence to Nordic dietary patterns is associated with generally small important reductions in the risk of major CVD outcomes and diabetes, which are supported by similar reductions in LDL-cholesterol and other intermediate cardiometabolic risk factors. The available evidence provides a generally good indication of the likely benefits of Nordic dietary patterns in people with or at risk for diabetes. REGISTRATION: ClinicalTrials.gov NCT04094194. FUNDING: Diabetes and Nutrition Study Group of the EASD Clinical Practice.

Advanced detection strategies for cardiotropic virus infection in a cohort study of heart failure patients.

The prevalence and contribution of cardiotropic viruses to various expressions of heart failure are increasing, yet primarily underappreciated and underreported due to variable clinical syndromes, a lack of consensus diagnostic standards and insufficient clinical laboratory tools. In this study, we developed an advanced methodology for identifying viruses across a spectrum of heart failure patients. We designed a custom tissue microarray from 78 patients with conditions commonly associated with virus-related heart failure, conditions where viral contribution is typically uncertain, or conditions for which the etiological agent remains suspect but elusive. Subsequently, we employed advanced, highly sensitive in situ hybridization to probe for common cardiotropic viruses: adenovirus 2, coxsackievirus B3, cytomegalovirus, Epstein-Barr virus, hepatitis C and E, influenza B and parvovirus B19. Viral RNA was detected in 46.4% (32/69) of heart failure patients, with 50% of virus-positive samples containing more than one virus. Adenovirus 2 was the most prevalent, detected in 27.5% (19/69) of heart failure patients, while in contrast to previous reports, parvovirus B19 was detected in only 4.3% (3/69). As anticipated, viruses were detected in 77.8% (7/9) of patients with viral myocarditis and 37.5% (6/16) with dilated cardiomyopathy. Additionally, viruses were detected in 50% of patients with coronary artery disease (3/6) and hypertrophic cardiomyopathy (2/4) and in 28.6% (2/7) of transplant rejection cases. We also report for the first time viral detection within a granulomatous lesion of cardiac sarcoidosis and in giant cell myocarditis, conditions for which etiological agents remain unknown. Our study has revealed a higher than anticipated prevalence of cardiotropic viruses within cardiac muscle tissue in a spectrum of heart failure conditions, including those not previously associated with a viral trigger or exacerbating role. Our work forges a path towards a deeper understanding of viruses in heart failure pathogenesis and opens possibilities for personalized patient therapeutic approaches.

Adolescent female rats recovered from the activity-based anorexia display blunted hedonic responding.

OBJECTIVE: As patients with anorexia nervosa tend to "like" palatable tastants less than controls, we set out to model this preclinically by using the taste reactivity test (TRT) to assess hedonic state in rats following weight restoration from a bout of activity-based anorexia (ABA). METHOD: Female rats (n = 31) were surgically implanted with an intraoral catheter, which allowed experimenters to assess baseline TRT to six tastants. Following baseline TRT, animals were either exposed to the activity-based anorexia condition (ABA; 1.5HR chow/ad lib wheel until 25% weight loss), kept sedentary (SED; ad lib chow/locked wheel), given access to running wheels with ad lib chow access (RW; ad lib chow/wheel), or were body weight matched to the ABA group (BWM; restricted chow/locked wheel). Following 25% weight loss, wheels were locked and food returned to ABA rats. Paired RW groups had their wheels locked and paired BWM rats were given ad lib access to food. Animals were given 10 days to recover prior to a second TRT. Videos were analyzed for liking (tongue protrusions) and disliking (gape) behaviors. RESULTS: The ABA group displayed a significant within-subject reduction in cumulative lick responses to water and 1 M sucrose. Additionally, we found the SED and ABA group displayed a significant within-subject reduction in cumulative lick responses to .1 M sucrose. Positive hedonic responses did not decline in either the BWM or the RW groups. DISCUSSION: The data show a novel phenomenon that a history of ABA results in an anhedonia phenotype that mirrors aspects of AN. SIGNIFICANCE STATEMENT: Patients recovered from anorexia nervosa report anhedonia, or the lack of pleasure in consuming palatable foods. Unfortunately, the biological mechanism underpinning anhedonia in anorexia nervosa is not well understood. The current study assessed hedonic state in adolescent female rats prior to and 10 days recovered following the activity-based anorexia paradigm. Age-matched, running wheel-matched and body weight-matched control groups were also tested at the same time points.

Changing HCW attitudes: a case study of normalizing HIV service delivery in emergency departments.

BACKGROUND: Delays in the implementation of evidence-based practices are significant and ubiquitous, compromising health outcomes. Resistance to change is a key factor in hindering adoption and integration of new evidence-based interventions. This study seeks to understand the impact of exposure to HIV testing within a research context on provider attitudes towards HIV counselling and testing (HCT) in emergency departments (ED). METHODS: This is a pre-and-post study design measuring the effect of a new ED-based HCT intervention, conducted by lay counsellors, on provider attitudes in Eastern Cape, South Africa. A validated, anonymized, 7-item survey was self-completed by routine care providers (physicians, nurses, and case managers). Questions were scored on a 5-point Likert scale with 5 consistently reflecting a positive attitude. Mean scores were calculated for each question and compared using a two-sample t-test to assess change in sample means for attitudes among providers surveyed before and after the intervention. RESULTS: A total of 132 surveys were completed across three EDs. Majority of respondents were female (70.5%), 20-29 years old (37.9%), of African race (81.1%), nurses (39.4%), and practicing medicine for 0-4 years (37.9%). Pre-intervention, providers displayed a positive attitude towards 'the benefit of offering ED-based HCT to patients' (4.33), 'the ED offering HCT' (3.53), 'all ED patients receiving HCT' (3.42), 'concern about patient reaction to HCT' (3.26), and 'comfort with disclosing HCT results' (3.21); and a mildly negative attitude towards 'only high-risk ED patients receiving HCT' (2.68), and 'the burden of offering HCT in a clinical environment' (2.80). Post-intervention, provider attitudes improved significantly towards 'all ED patients receiving HCT' (3.86, p < 0.05), 'only high-risk ED patients receiving HCT' (2.30, p < 0.05), 'the burden of offering HCT in a clinical environment' (3.21, p < 0.05), and 'comfort with disclosing HCT results' (3.81, p < 0.05). CONCLUSIONS: Controlled exposure to new practices with a structured implementation period can shift attitudes beginning a process of practice normalization. In our study, we observed improvements in provider attitudes regarding the benefits of HCT and the burden of offering HCT to all patients in the ED. Research activities may have a role in mitigating resistance to change and supporting intervention adoption.

A pilot study to screen for poor academic performance in children with sickle cell disease in the outpatient setting.

BACKGROUND: Children with sickle cell disease (SCD) are at risk for neurocognitive deficits, which can lead to effects on academic performance and later job attainment. However, screening in children at high risk for poor academic performance (PAP) in a clinic setting has been limited. The goal was to identify young children with SCD at high risk for PAP via administration of a standardized screening tool at the clinic visit. PROCEDURE: Parents of 20 patients were asked to complete the Behavior Assessment System for Children, 3rd edition (BASC-3) Parent Rating Scale. Children ages six to nine years and all SCD genotypes were included. Those patients who scored at least 1 standard deviation below the mean were considered high risk. Statistics was used to associate demographic, academic, and laboratory data with risk status (RS). RESULTS: Four of 20 patients (20%) were found to be at risk by the BASC-3. A significant association was found between those with a history of PAP and RS (P = 0.001). A trend toward association was found between baseline hemoglobin, reticulocyte count, and RS. Children not at risk had a higher hemoglobin level and lower reticulocyte count (P = 0.37 and P = 0.20, respectively). Those on hydroxyurea were significantly less likely to score as at risk (P = 0.014), whereas those with siblings may be at greater risk (P = 0.037). CONCLUSION(S): A parent-directed screening tool may identify children with SCD in need of additional school support. Further prospective studies are necessary to understand correlations found between hemoglobin, reticulocyte count, and hydroxyurea treatment and risk for PAP.

Contact Engineering High-Performance n-Type MoTe2 Transistors.

Semiconducting MoTe2 is one of the few two-dimensional (2D) materials with a moderate band gap, similar to silicon. However, this material remains underexplored for 2D electronics due to ambient instability and predominantly p-type Fermi level pinning at contacts. Here, we demonstrate unipolar n-type MoTe2 transistors with the highest performance to date, including high saturation current (>400 µA/µm at 80 K and >200 µA/µm at 300 K) and relatively low contact resistance (1.2 to 2 kΩ·µm from 80 to 300 K), achieved with Ag contacts and AlOx encapsulation. We also investigate other contact metals (Sc, Ti, Cr, Au, Ni, Pt), extracting their Schottky barrier heights using an analytic subthreshold model. High-resolution X-ray photoelectron spectroscopy reveals that interfacial metal-Te compounds dominate the contact resistance. Among the metals studied, Sc has the lowest work function but is the most reactive, which we counter by inserting monolayer hexagonal boron nitride between MoTe2 and Sc. These metal-insulator-semiconductor (MIS) contacts partly depin the metal Fermi level and lead to the smallest Schottky barrier for electron injection. Overall, this work improves our understanding of n-type contacts to 2D materials, an important advance for low-power electronics.

Single cell sequencing reveals gene expression signatures associated with bone marrow stromal cell subpopulations and time in culture.

BACKGROUND: Bone marrow stromal cells (BMSCs) are a heterogeneous population that participates in wound healing, immune modulation and tissue regeneration. Next generation sequencing was used to analyze transcripts from single BMSCs in order to better characterize BMSC subpopulations. METHODS: Cryopreserved passage 2 BMSCs from one healthy subject were cultured through passage 10. The transcriptomes of bulk BMSCs from designated passages were analyzed with microarrays and RNA sequencing (RNA-Seq). For some passages, single BMSCs were separated using microfluidics and their transcriptomes were analyzed by RNA-Seq. RESULTS: Transcriptome analysis by microarray and RNA-Seq of unseparated BMSCs from passages 2, 4, 6, 8, 9 and 10 yielded similar results; both data sets grouped passages 4 and 6 and passages 9 and 10 together and genes differentially expressed among these early and late passage BMSCs were similar. 3D Diffusion map visualization of single BMSCs from passages 3, 4, 6, 8 and 9 clustered passages 3 and 9 into two distinct groups, but there was considerable overlap for passages 4, 6 and 8 cells. Markers for early passage, FGFR2, and late passage BMSCs, PLAT, were able to identify three subpopulations within passage 3 BMSCs; one that expressed high levels of FGFR2 and low levels of PLAT; one that expressed low levels of FGFR2 and high levels of PLAT and one that expressed intermediate levels of FGFR2 and low levels of PLAT. CONCLUSIONS: Single BMSCs can be separated by microfluidics and their transcriptome analyzed by next generation sequencing. Single cell analysis of early passage BMSCs identified a subpopulation of cells expressing high levels of FGFR2 that might include skeletal stem cells.

When Do Clinicians Decide to Screen Children for Mental Health-Behavioral-Developmental Delays/Disorders: Is it Time to Reconsider Policy Recommendations?

OBJECTIVES: To determine at which ages providers choose to screen for mental, behavioral, and developmental disorder/delay (MBDD), and what they find; and which, if any, public and professional guidelines are most effective at identification. STUDY DESIGN: Naturalistic retrospective cohort study of 215 general pediatric and family practice clinics within 24 US states involving 160 634 encounters during which MBDD screening tests were administered. RESULTS: Almost all clinicians (96%) administered screens at ages targeted by the American Academy of Pediatrics (AAP), that is, 9, 18, 24, and/or 30 months of age, but also at younger and older ages: 57% opted to screen at ≥5 years of age. Of the 8% of children at risk for probable MBDD, 27% were detected at American Academy of Pediatrics-targeted ages-71% across the birth to 5-year age range and an additional 29% at ≥5 years of age. Children >30 months of age were 3 times more likely to have probable MBDD than were younger children, and those >5 years of age were almost 4 times more likely to have probable MBDD. Older children were more likely to have psychosocial risk factors, but age itself was the most powerful predictor. CONCLUSIONS: Most clinicians preferred to screen across the birth to 8-year age range and their findings revealed that most MBDDs cannot be detected in the earliest years of life. Policies regarding the timing of screening should be expanded to include all well visits and between visits if needed.

Are you ready? A systematic review of pre-departure resources for global health electives.

BACKGROUND: There has been an exponential increase in the offering of short-term international field experiences in recent years in response to student demands for global health opportunities. Pre-departure preparation is an essential component to equip trainees with the adequate safety, wellness, and cultural competence needed to engage in a meaningful and mutually beneficial elective. This review seeks to quantify the plethora of pre-departure preparation training available to public health, clinical, and undergraduate trainees across the continuum of education for short-term experiences in low-and middle-income countries (LMICs). METHODS: We performed a systematic review of Pubmed, Embase, Web of Science, Scopus, and Ovid Global Health in February, 2018. A three-concept search was employed and included "global or international health"; "education or preparation of personnel/students"; and "field programs or travel." The study teamed used PRISMA reporting guidelines to conduct title and full-text reviews and conduct data extraction and analysis. RESULTS: The search returned 2506 unique articles. Of these, 55 met inclusion criteria and were included in the final review. Ninety one percent (91%) of articles focused on pre-departure trainings for medical students and residents. Nine thematic domains for short-term international field experiences emerged; culture, safety, and project-specific knowledge were the most frequently covered domains while mentorship, professionalism, and emotional wellness and culture shock were least common. Approximately half (53.3%) of studies specifically evaluated the pre-departure component of the international experience using a survey or evaluation form. Recommendations emerged from these evaluations including early engagement with international partners, inclusion of self-reflection exercises and site-specific content, and utilization of interactive approaches in learning. Some institutions face barriers to conducting pre-departure preparation such as lack of dedicated faculty, finances, and institutional support. CONCLUSIONS: Interest in pre-departure training for international experiences is growing but few programs conduct and publish evaluations of these trainings. Pre-departure trainings should be developed in partnership with receiving institutions and faculty and incorporate critical self- reflection throughout the experience. In addition to the experience itself, institutions need to evaluate these curricula to better understand how they influence trainees' capacity to effectively engage in LMIC settings.

Effects of Molecular Structure and Solvent Polarity on Adsorption of Carboxylic Anchoring Dyes onto TiO2 Particles in Aprotic Solvents.

Interactions of molecules with the surface of TiO2 particles are of fundamental and technological importance. One example is that the adsorption density and energy of the dye molecules on TiO2 particles affect the efficiency of dye-sensitized solar cells (DSSC). In this work, we present measurements characterizing the adsorption of the two isomers, para-ethyl red (p-ER) and ortho-ethyl red (o-ER), of a dye molecule potentially applicable for DSSC onto TiO2 particles by second harmonic scattering (SHS). It is found that while at the wavelengths used here o-ER has a much bigger molecular hyperpolarizability, p-ER exhibits strong SHS responses but o-ER gives no detectable SHS when the dyes are added to the TiO2 colloids, respectively. This observation indicates that o-ER does not adsorb onto TiO2, likely due to steric hindrance. Furthermore, we investigate how solvents affect the surface adsorption strength and density of p-ER onto TiO2 in four aprotic solvents with varying polarity. The absolute magnitude of the adsorption free energy was found to increase with the specific solvation energy that represents the ability of accepting electrons and solvent polarity. It is likely that resolvation of the solvent molecules displaced by the adsorption of the dye molecule at the surface in stronger electron-accepting and more polar solvents results in a larger adsorption free energy for the dye adsorption.