Exploring the potential of meeting adolescent girls' nutrient needs in urban Colombia using food-based recommendations.

During adolescence, many young people gain greater food choice agency but also become increasingly exposed and susceptible to environmental pressures that influence their food choices. This coincides with increased nutritional needs, especially for girls. In urban Colombia, adolescent diets are often high in undesirable foods and low in nutritious foods, contributing to overweight and micronutrient deficiencies. This study aimed to explore the potential of improving diet quality using food-based recommendations (FBRs) within the parameters of local food systems and adolescents' existing dietary patterns to inform context-specific programmatic responses to malnutrition. We applied linear programming analysis to dietary data from 13- to 20-year-old girls in Medellin to identify problem nutrients, local micronutrient sources, and promising FBRs. Iron and, to a lesser extent, calcium targets were difficult to meet using optimized diets based on local foods, especially for 13- to 17-year-olds. High habitual consumption of foods with excessive salt, fat, or sugar provided >5% of micronutrients in optimized diets. Otherwise, significant micronutrient sources included legumes, meat, dairy, bread, potatoes, and fruit. FBRs met targets for 10 micronutrients but only 32%-39% recommended nutrient intake for iron. FBRs, including occasionally consumed foods and supplements, met all intake targets for less cost, indicating a need to increase access to nutrient-dense products.

Locally relevant food-based recommendations could increase iron and calcium intake for adolescent girls in Vietnam.

Unhealthy eating habits are common among adolescents in Vietnam, where transitioning food environments increasingly offer energy-dense micronutrient-poor foods. Successful behavior change approaches must be feasible and acceptable, promoting local foods that are available, accessible, and preferred. Yet, few studies have investigated the potential of food-based approaches for adolescents. We used linear programming to identify problem nutrients, local nutrient sources, and realistic food-based recommendations (FBRs) to improve nutrient intake among girls 16-22 years in Thai Nguyen, Vietnam. We then identified a reduced set of FBRs to prioritize the most critical micronutrient gaps. Calcium and iron targets could not be met in any realistic diet modeling scenario. The best set of FBRs included seven recommendations which could meet intake targets for 9 of 11 modeled micronutrients. The best reduced set of three FBRs targeting iron and calcium only-although more feasible for behavior change-was less effective at improving intake of these nutrients since fewer foods were recommended. Given the difficulty of meeting calcium and iron targets using local foods within acceptable dietary patterns, additional interventions, such as supplementation, staple food fortification, or increasing the availability of affordable calcium- and iron-rich foods, may be necessary to promote dietary adequacy for adolescent girls.

Including calcium-fortified water or flour in modeled diets based on local foods could improve calcium intake for women, adolescent girls, and young children in Bangladesh, Uganda, and Guatemala.

Adequate calcium intake is essential for health, especially for infants, children, adolescents, and women, yet is difficult to achieve with local foods in many low- and middle-income countries. Previous analysis found it was not always possible to identify food-based recommendations (FBRs) that reached the calcium population recommended intake (PRI) for these groups in Bangladesh, Guatemala, and Uganda. We have modeled the potential contribution of calcium-fortified drinking water or wheat flour to FBR sets, to fill the remaining intake gaps. Optimized diets containing fortified products, with calcium-rich local foods, achieved the calcium PRI for all target groups. Combining fortified water or flour with FBRs met dietary intake targets for adolescent girls in all geographies and allowed a reduction from 3-4 to the more feasible 1-2 FBRs. Water with a calcium concentration of 100 mg/L with FBRs was sufficient to meet calcium targets in Uganda, but higher concentrations (400-500 mg/L) were mostly required in Guatemala and Bangladesh. Combining calcium-fortified wheat flour at 400 mg/100 g of flour and the FBR for small fish resulted in diets meeting the calcium PRI in Bangladesh. Calcium-fortified water or flour could improve calcium intake for vulnerable populations, especially when combined with FBRs based on locally available foods.

Could local foods achieve recommended calcium intakes for nutritionally vulnerable populations in Uganda, Guatemala, and Bangladesh?

Globally, dietary intake of calcium is often insufficient, and it is unclear if adequacy could be achieved by promoting calcium-rich local foods. This study used linear programming and household consumption data from Uganda, Bangladesh, and Guatemala to assess whether local foods could meet calcium population reference intakes (Ca PRIs). The most promising food-based approaches to promote dietary calcium adequacy were identified for 12- to 23-month-old breastfed children, 4- to 6-year-old children, 10- to 14-year-old girls, and nonpregnant and nonbreastfeeding (NPNB) women of reproductive age living in two regions of each country. Calcium-optimized diets achieved 75-253% of the Ca PRI, depending on the population, and were <100% for 4- to 6-year-olds in one region of each country and 10- to 14-year-old girls in Sylhet, Bangladesh. The best food sources of calcium were green leafy vegetables and milk, across geographic locations, and species of small fish, nixtamalized (lime-treated) maize products, sesame seeds, and bean varieties, where consumed. Food-based recommendations (FBRs) achieving the minimum calcium threshold were identified for 12- to 23-month-olds and NPNB women across geographic locations, and for 4- to 6-year-olds and 10-to 14-year-old girls in Uganda. However, for 4- to 6-year-olds and 10- to 14-year-old girls in Bangladesh and Guatemala, calcium-adequate FBRs could not be identified, indicating a need for alternative calcium sources or increased access to and consumption of local calcium-rich foods.

Nutrition modeling tools: a qualitative study of influence on policy decision making and determining factors.

Nutrition modeling tools (NMTs) generate evidence to inform policy and program decision making; however, the literature is generally limited to modeling methods and results, rather than use cases and their impacts. We aimed to document the policy influences of 12 NMTs and identify factors influencing them. We conducted semistructured interviews with 109 informants from 30 low- and middle-income country case studies and used thematic analysis to understand the data. NMTs were mostly applied by international organizations to inform national government decision making. NMT applications contributed to enabling environments for nutrition and influenced program design and policy in most cases; however, this influence could be strengthened. Influence was shaped by processes for applying the NMTs; ownership of the analysis and data inputs, and capacity building in NMT methods, encouraged uptake. Targeting evidence generation at specific policy cycle stages promoted uptake; however, where advocacy capacity allowed, modeling was embedded ad hoc into emerging policy discussions and had broader influence. Meanwhile, external factors, such as political change and resource constraints of local partner organizations, challenged NMT implementation. Importantly, policy uptake was never the result of NMTs exclusively, indicating they should be nested persistently and strategically within the wider evidence and advocacy continuum, rather than being stand-alone activities.

Household-level consumption data can be redistributed for individual-level Optifood diet modeling: analysis from four countries.

A barrier to using Optifood linear programming (LP), which identifies nutrient gaps and supports population-specific food-based recommendation (FBR) development, is the requirement for dietary intake data. We investigated whether Household Consumption and Expenditure Surveys (HCESs) could be used instead of individual-level 24-h recalls (24HRs). The 24HR data from 12- to 23-month-old breastfeeding children in rural Kenya, Uganda, Guatemala, and Bangladesh were paired with HCES food consumption data from similar areas (n = 8) and time periods. HCES food intakes (g/week) were estimated using adult male equivalents, adjusted for breastfeeding. Paired HCES- and 24HR-defined LP inputs and outputs were compared using percentage agreement. Mean overall percentage agreements were 42%, 63%, and 80%, for food, food subgroup, and food-group model parameters, respectively. HCES food lists were on average 1.3 times longer than 24HR. Similar nutrient gaps (77-100% agreement), food sources of nutrients (71-100% agreement), and FBRs (80-100% agreement) were identified. The results suggest that HCES data can be used in Optifood analyses for 12- to 23-month-old children, despite recognized challenges of using it to estimate dietary intakes of young children compared with older age groups. Further analyses, however, are required for different age groups and locations to confirm expectations that it would perform equally well.

The Effects of Choice on the Reading Comprehension and Enjoyment of Children with Severe Inattention and no Attentional Difficulties.

It has been proposed that enhancing motivation supports the learning of children with Attention Deficit Hyperactivity Disorder (ADHD). Less is known if inattentive children with no ADHD diagnosis may similarly benefit, when being motivated to engage in an academic task. Using a repeated-measures design, this study investigated the effects of text choice as an intrinsic motivator on the reading comprehension and enjoyment of Year 4 children attending mainstream primary schools (N = 92; aged 8-9 years; 48 boys); comparing those with no attentional difficulties and severe inattention. We hypothesized that 1) choice would increase reading comprehension and enjoyment 2) choice would increase the reading comprehension and enjoyment of children both with severe inattention and no attentional difficulties 3) choice effects would be significantly greater for children with severe inattention than those with no attentional difficulties. Children participated in a reading intervention that included a Choice (experimental) and a No Choice (control) condition. Child inattention was measured via a Virtual Reality Continuous Performance Task (Omission errors, Reaction Time Variability) and Teacher Ratings. Choice significantly increased reading comprehension, but not enjoyment compared with no choice. Choice improved the reading comprehension of children with both severe inattention and no attentional difficulties. Choice did not benefit the reading of severely inattentive children more than that of children with no attentional difficulties. These findings underline the educational benefits of choice for young readers both with severe inattention and no attentional difficulties, which are further discussed drawing on existing theory and research.

Engineering Vaccines for Tissue-Resident Memory T Cells.

In recent years, tissue-resident memory T cells (TRM) have attracted significant attention in the field of vaccine development. Distinct from central and effector memory T cells, TRM cells take up residence in home tissues such as the lung or urogenital tract and are ideally positioned to respond quickly to pathogen encounter. TRM have been found to play a role in the immune response against many globally important infectious diseases for which new or improved vaccines are needed, including influenza and tuberculosis. It is also increasingly clear that TRM play a pivotal role in cancer immunity. Thus, vaccines that can generate this memory T cell population are highly desirable. The field of immunoengineering-that is, the application of engineering principles to study the immune system and design new and improved therapies that harness or modulate immune responses-is ideally poised to provide solutions to this need for next-generation TRM vaccines. This review covers recent developments in vaccine technologies for generating TRM and protecting against infection and cancer, including viral vectors, virus-like particles, and synthetic and natural biomaterials. In addition, it offers critical insights on the future of engineering vaccines for tissue-resident memory T cells.

Co-delivery of Peptide Neoantigens and Stimulator of Interferon Genes Agonists Enhances Response to Cancer Vaccines.

Cancer vaccines targeting patient-specific neoantigens have emerged as a promising strategy for improving responses to immune checkpoint blockade. However, neoantigenic peptides are poorly immunogenic and inept at stimulating CD8+ T cell responses, motivating a need for new vaccine technologies that enhance their immunogenicity. The stimulator of interferon genes (STING) pathway is an endogenous mechanism by which the innate immune system generates an immunological context for priming and mobilizing neoantigen-specific T cells. Owing to this critical role in tumor immune surveillance, a synthetic cancer nanovaccine platform (nanoSTING-vax) was developed that mimics immunogenic cancer cells in its capacity to efficiently promote co-delivery of peptide antigens and the STING agonist, cGAMP. The co-loading of cGAMP and peptides into pH-responsive, endosomolytic polymersomes promoted the coordinated delivery of both cGAMP and peptide antigens to the cytosol, thereby eliciting inflammatory cytokine production, co-stimulatory marker expression, and antigen cross-presentation. Consequently, nanoSTING-vax significantly enhanced CD8+ T cell responses to a range of peptide antigens. Therapeutic immunization with nanoSTING-vax, in combination with immune checkpoint blockade, inhibited tumor growth in multiple murine tumor models, even leading to complete tumor rejection and generation of durable antitumor immune memory. Collectively, this work establishes nanoSTING-vax as a versatile platform for enhancing immune responses to neoantigen-targeted cancer vaccines.

Does the language we use to segment the body, shape the way we perceive it? A study of tactile perceptual distortions.

Tactile perception is referenced to, and modulated by, body parts and their boundaries. For example, tactile distances presented over the wrist are perceptually elongated relative to those presented within the hand or arm. This phenomenon is argued to result from a segmentation of tactile space according to body parts and their boundaries, i.e., touches presented within a body part are perceived as being more similar, and therefore closer together, whereas those that straddle a body part boundary (e.g. presented across two body parts) are perceived as more distinct and thus further apart. We tested the hypothesis that language shapes this effect by providing consolidatory labels for categories and boundaries, as it does in other perceptual domains. We examined the perceptual elongation of distance over the wrist in a group of Croatian adults (n = 37) whose first language does not differentiate between hand and arm at the wrist in common noun terms (instead, the Croatian word "ruka" encompasses the entire limb). Croatian adults, like UK adults reported in a previous study (Le Cornu Knight, Longo, & Bremner, 2014), perceived distances presented proximodistally over the wrist boundary as longer than those presented mediolaterally, whereas the reverse was found for both the hand and the arm. This pattern of results was remained when Croatian participants were split into two groups of inexperienced or proficient English-language speakers. This is striking evidence that body part boundaries consistently modulate tactile perception, despite differences in the linguistic distinctions of such body parts made by one's first language.

Mucosal Immunization with a pH-Responsive Nanoparticle Vaccine Induces Protective CD8+ Lung-Resident Memory T Cells.

Tissue-resident memory T cells (TRM) patrol nonlymphoid organs and provide superior protection against pathogens that commonly infect mucosal and barrier tissues, such as the lungs, intestine, liver, and skin. Thus, there is a need for vaccine technologies that can induce a robust, protective TRM response in these tissues. Nanoparticle (NP) vaccines offer important advantages over conventional vaccines; however, there has been minimal investigation into the design of NP-based vaccines for eliciting TRM responses. Here, we describe a pH-responsive polymeric nanoparticle vaccine for generating antigen-specific CD8+ TRM cells in the lungs. With a single intranasal dose, the NP vaccine elicited airway- and lung-resident CD8+ TRM cells and protected against respiratory virus challenge in both sublethal (vaccinia) and lethal (influenza) infection models for up to 9 weeks after immunization. In elucidating the contribution of material properties to the resulting TRM response, we found that the pH-responsive activity of the carrier was important, as a structurally analogous non-pH-responsive control carrier elicited significantly fewer lung-resident CD8+ T cells. We also demonstrated that dual-delivery of protein antigen and nucleic acid adjuvant on the same NP substantially enhanced the magnitude, functionality, and longevity of the antigen-specific CD8+ TRM response in the lungs. Compared to administration of soluble antigen and adjuvant, the NP also mediated retention of vaccine cargo in pulmonary antigen-presenting cells (APCs), enhanced APC activation, and increased production of TRM-related cytokines. Overall, these data suggest a promising vaccine platform technology for rapid generation of protective CD8+ TRM cells in the lungs.

Poor Sleep Has Negative Implications for Children With and Without ADHD, but in Different Ways.

Background: Sleep problems are commonly reported in attention deficit hyperactivity disorder (ADHD), and are also a familiar characteristic of typical development (TD). We sought to elucidate the relationship between sleep, ADHD trait behaviors, and cognitive inattention, and how it manifests between ADHD and TD children. Participants: Eighteen children diagnosed with ADHD and 20 age-matched TD controls aged 5 to 11 years old participated in the study. Methods: Sleep profiles were assessed using Children's Sleep Habits Questionnaire and actigraphy measures. Behavioral functioning was examined using Conners' Parent Report Scale and attention using the computerized Conners' Continuous Performance Task. Results: We found evidence of (a) poorer sleep quality in the ADHD group, despite no difference in actual sleep time, (b) poor sleep quality in TD children predicting increased ADHD-trait behaviors, despite no association with attention, and (c) a consistent trend for poor sleep quality predicting reduced attentional control in ADHD children, despite no association with behavior. Conclusions: Poor sleep quality affects developmental subgroups in different ways. For ADHD children, poor sleep worsens their predisposed attentional deficit, while for TD children it mimics ADHD behaviors. These findings have important implications for the debate on overdiagnosis of childhood ADHD, and the use of sleep-based interventions. Above all, they highlight the importance of promoting good sleep hygiene in all children.

Poly(propylacrylic acid)-peptide nanoplexes as a platform for enhancing the immunogenicity of neoantigen cancer vaccines.

Cancer vaccines targeting patient-specific tumor neoantigens have recently emerged as a promising component of the rapidly expanding immunotherapeutic armamentarium. However, neoantigenic peptides typically elicit weak CD8+ T cell responses, and so there is a need for universally applicable vaccine delivery strategies to enhance the immunogenicity of these peptides. Ideally, such vaccines could also be rapidly fabricated using chemically synthesized peptide antigens customized to an individual patient. Here, we describe a strategy for simple and rapid packaging of peptide antigens into pH-responsive nanoparticles with endosomal escape activity. Electrostatically-stabilized polyplex nanoparticles (nanoplexes) can be assembled instantaneously by mixing decalysine-modified antigenic peptides and poly(propylacrylic acid) (pPAA), a polyanion with pH-dependent, membrane destabilizing activity. These nanoplexes increase and prolong antigen uptake and presentation on MHC-I (major histocompatibility complex class I) molecules expressed by dendritic cells, resulting in enhanced activation of CD8+ T cells. Using an intranasal immunization route, nanoplex vaccines inhibit formation of lung metastases in a murine melanoma model. Additionally, nanoplex vaccines strongly synergize with the adjuvant α-galactosylceramide (α-GalCer) in stimulating robust CD8+ T cell responses, significantly increasing survival time in mice with established melanoma tumors. Collectively, these findings demonstrate that peptide/pPAA nanoplexes offer a facile and versatile platform for enhancing CD8+ T cell responses to peptide antigens, with potential to complement ongoing advancements in the development of neoantigen-targeted cancer vaccines.

Fatty Acid-Mimetic Micelles for Dual Delivery of Antigens and Imidazoquinoline Adjuvants.

Vaccine design has undergone a shift towards the use of purified protein subunit vaccines, which offer increased safety and greater control over antigen specificity, but at the expense of immunogenicity. Here we report the development of a new polymer-based vaccine delivery platform engineered to enhance immunity through the co-delivery of protein antigens and the Toll-like receptor 7 (TLR7) agonist imiquimod (IMQ). Owing to the preferential solubility of IMQ in fatty acids, a series of block copolymer micelles with a fatty acid-mimetic core comprising lauryl methacrylate (LMA) and methacrylic acid (MAA), and a poly(ethylene glycol) methyl ether methacrylate (PEGMA) corona decorated with pyridyl disulfide ethyl methacrylate (PDSM) moieties for antigen conjugation were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Carriers composed of 50 mole% LMA (LMA50) demonstrated the highest IMQ loading (2.2 w/w%) and significantly enhanced the immunostimulatory capacity of IMQ to induce dendritic cell maturation and proinflammatory cytokine production. Conjugation of a model antigen, ovalbumin (OVA), to the corona of IMQ-loaded LMA50 micelles enhanced in vitro antigen uptake and cross-presentation on MHC class I (MHC-I). A single intranasal (IN) immunization of mice with carriers co-loaded with IMQ and OVA elicited significantly higher pulmonary and systemic CD8+ T cell responses and increased serum IgG titer relative to a soluble formulation of antigen and adjuvant. Collectively, these data demonstrate that rationally designed fatty acid-mimetic micelles enhance intracellular antigen and IMQ delivery and have potential as synthetic vectors for enhancing the immunogenicity of subunit vaccines.

Part-based representations of the body in early childhood: evidence from perceived distortions of tactile space across limb boundaries.

Studies show that touch in adults is referenced to a representation of the body that is structured topologically according to body parts; the perceived distance between two stimuli crossing over a body part boundary is elongated relative to the perceived distance between two stimuli presented within one body part category. Here we investigate this influence of body parts on tactile space perception in children of 5, 6 and 7 years of age. We presented children with pairs of tactile stimuli on the left hand/arm, either within the hand, within the forearm, or over the wrist. With their eyes closed children were asked to adjust the distance between the thumb and forefinger of their right hand to represent the felt distance between the two tactile stimuli. Like adults, the children perceived the distance between two stimuli that cross the body part boundary to be further apart than those that were presented within the hand or arm. They also perceive tactile distance to be greater on the hand than the arm which is the first observation of Weber's illusion in young children. We propose that a topological mode of body representation is particularly advantageous during early life given that body part categories remain constant while the metric proportions of the body change substantially as the child grows.

Eliciting Epitope-Specific CD8+ T Cell Response by Immunization with Microbial Protein Antigens Formulated with α-Galactosylceramide: Theory, Practice, and Protocols.

CD8+ cytotoxic T lymphocytes confer protection against infectious diseases caused by viruses, bacteria, and parasites. Hence, significant efforts have been invested into devising ways to generate CD8+ T cell-targeted vaccines. Generation of microbe-free protein subunit vaccines requires a thorough knowledge of protective target antigens. Such antigens are proteolytically processed peptides presented by MHC class I molecules. To induce a robust antigen-specific CD8+ T cell response through vaccination, it is essential to formulate the antigen with an effective adjuvant. Here, we describe a versatile method for generating high-frequency antigen-specific CD8+ T cells through immunization of mice using the invariant natural killer T cell agonist α-galactosylceramide as the adjuvant.

Context-specific complementary feeding recommendations developed using Optifood could improve the diets of breast-fed infants and young children from diverse livelihood groups in northern Kenya.

OBJECTIVE: To formulate age- and context-specific complementary feeding recommendations (CFR) for infants and young children (IYC) and to compare the potential of filling population-level nutrient gaps using common sets of CFR across age groups. DESIGN: Linear programming was used to develop CFR using locally available and acceptable foods based on livelihood- and age-group-specific dietary patterns observed through 24 h dietary recalls. Within each livelihood group, the nutrient potential of age-group-specific v. consolidated CFR across the three age groups was tested. SETTING: Three food-insecure counties in northern Kenya; namely, settled communities from Isiolo (n 300), pastoralist communities from Marsabit (n 283) and agro-pastoralist communities from Turkana (n 299). SUBJECTS: Breast-fed IYC aged 6-23 months (n 882). RESULTS: Age-specific CFR could achieve adequacy for seven to nine of eleven modelled micronutrients, except among 12-23-month-old children in agro-pastoralist communities. Contribution of Fe, Zn and niacin remained low for most groups, and thiamin, vitamin B6 and folate for some groups. Age-group-consolidated CFR could not reach the same level of nutrient adequacy as age-specific sets among the settled and pastoralist communities. CONCLUSIONS: Context- and age-specific CFR could ensure adequate levels of more modelled nutrients among settled and pastoralist IYC than among agro-pastoralist communities where use of nutrient-dense foods was limited. Adequacy of all eleven modelled micronutrients was not achievable and additional approaches to ensure adequate diets are required. Consolidated messages should be easier to implement as part of a behaviour change strategy; however, they would likely not achieve the same improvements in population-level dietary adequacy as age-specific CFR.

The Role of Environmental Factors on Sleep Patterns and School Performance in Adolescents.

BACKGROUND: Modern life, with its many distractions, is seeing sleep quantity and quality decline during adolescence. This is a concern as research persuasively demonstrates the negative impact of reduced sleep on academic achievement, both in terms of learning and behavior. AIMS: This study examined the relationship between sleep and school functioning in adolescence, with a focus on environmental factors that might mediate this relationship. SAMPLE AND METHOD: Forty-seven adolescents took part. Sleep was measured using the School Sleep Habits Survey (SSHS) and a sleep diary. School records of year grade point averages provided a measure of academic achievement. Raven's Standard Progressive Matrices gave a measure of general cognitive processing. Environmental sleep factors falling into three groups, namely, stimulant consumption, media use and exercise, were measured using a self-report questionnaire. RESULTS: An average of 7.08 h of sleep was reported. Correlations revealed that Total sleep time (TST) and bedtimes on weekdays were strongly associated with academic achievement. Morning/eveningness and sleep/wake behavior problems had a strong relationship with performance on the Ravens. Stimulant consumption and media use before bed revealed strong relationships with TST and bedtimes on weekdays. Crucially, mediation analyses confirmed that both caffeine consumption and electronic media use before bedtime were negatively associated with academic performance, via the mediating pathway by affecting sleep. Exercise was not associated with any of the sleep variables, but was associated with better academic performance. CONCLUSION: The current findings highlight that, now more than ever, parents, schools and policy makers must be aware of the negative effects of caffeinated substances marketed to students, and electronic media use on their sleep habits. Our findings suggest that targeting caffeine consumption and electronic media use before bed may represent effective routes in alleviating modern teenage sleep debt, and in turn enhancing academic performance.

Categorical perception of tactile distance.

The tactile surface forms a continuous sheet covering the body. And yet, the perceived distance between two touches varies across stimulation sites. Perceived tactile distance is larger when stimuli cross over the wrist, compared to when both fall on either the hand or the forearm. This effect could reflect a categorical distortion of tactile space across body-part boundaries (in which stimuli crossing the wrist boundary are perceptually elongated) or may simply reflect a localised increased in acuity surrounding anatomical landmarks (in which stimuli near the wrist are perceptually elongated). We tested these two interpretations across two experiments, by comparing a well-documented bias to perceive mediolateral tactile distances across the forearm/hand as larger than proximodistal ones along the forearm/hand at three different sites (hand, wrist, and forearm). According to the 'categorical' interpretation, tactile distances should be elongated selectively in the proximodistal axis thus reducing the anisotropy. According to the 'localised acuity' interpretation, distances will be perceptually elongated in the vicinity of the wrist regardless of orientation, leading to increased overall size without affecting anisotropy. Consistent with the categorical account, we found a reduction in the magnitude of anisotropy at the wrist, with no evidence of a corresponding localised increase in precision. These findings demonstrate that we reference touch to a representation of the body that is categorically segmented into discrete parts, which consequently influences the perception of tactile distance.

Synthesis and characterization of a poly(lactic-co-glycolic acid) core + poly(N-isopropylacrylamide) shell nanoparticle system.

Poly(lactic-co-glycolic acid) (PLGA) is a popular material used to prepare nanoparticles for drug delivery. However, PLGA nanoparticles lack desirable attributes including active targeting abilities, resistance to aggregation during lyophilization, and the ability to respond to dynamic environmental stimuli. To overcome these issues, we fabricated a nanoparticle consisting of a PLGA core encapsulated within a shell of poly(N-isopropylacrylamide). Dynamic light scattering and transmission electron microscope imaging were used to characterize the nanoparticles, while an MTT assay and ELISA suggested biocompatibility in THP1 cells. Finally, a collagen type II binding assay showed successful modification of these nanoparticles with an active targeting moiety.