Systematic Review and Meta-Analyses: Safety and Efficacy of Complementary and Alternative Treatments for Pediatric Attention-Deficit/Hyperactivity Disorder.

OBJECTIVE: Complementary and alternative treatments (CATs) for ADHD have proliferated over the past decade; however, their safety and efficacy remain uncertain. We completed a systematic review and meta-analyses across CAT domains. METHODS: Systematic search and data extraction identified randomized controlled trials for pediatric ADHD (ages 3-19 years) that included probably blind ADHD symptom outcome measures. We evaluated basic (RCT of a CAT compared with sham/placebo, attention/active control, treatment as usual, and waitlist control), complementary (RCTs comparing an evidence-based treatment with a CAT and the same evidence-based treatment), and alternative (evidence-based treatment to CAT) efficacy. Random-effect meta-analyses were conducted when at least 3 blinded studies were identified for a specific CAT domain. RESULTS: Eighty-seven of 2253 nonduplicate screened manuscripts met inclusion criteria. No study reported significantly greater adverse effects for CATs than controls; naturopathy reported fewer adverse effects than evidence-based treatments but did not demonstrate basic efficacy. In the systematic review of basic efficacy, evidence of effectiveness was mixed but replicated previous evidence for the possible efficacy of cognitive training, neurofeedback, and essential fatty acid supplementation for certain patients. With respect to alternative and complementary efficacy, no CAT outperformed or enhanced evidence-based treatments (stimulant medications and behavioral therapy) when replication was required. Individual meta-analyses indicated that cognitive training was the only CAT that demonstrated overall basic efficacy ( SMD = 0.216; p = 0.032). CONCLUSION: Clinicians may cautiously recommend (but monitor) cognitive training when evidence-based treatments are not feasible or effective for a patient. Additional studies are needed to further understand the potential of CAT domains.

Prevalence of raised body mass index in paediatric sickle cell disease.

AIM: Children with sickle cell disease (SCD) have historically weighed less than their healthy peers. More recently, a retrospective chart review from six institutions in New England reported nearly one-quarter of children and adolescents with SCD had raised body mass index (BMI). This study aimed to examine rates of children with SCD with raised BMI in Mississippi compared to state and national norms and assess the correlation between haemoglobin and BMI. METHODS: A retrospective chart review of paediatric patients with SCD at the University of Mississippi Medical Center (UMMC) was conducted using data from the most recent clinic visit. Mississippi and national weight status estimates for youth 10-17 years were obtained from the 2016-2017 National Survey of Children's Health. RESULTS: For youth 10-17 years with SCD (n = 345), 21.4.% of children with SS/Sß° and 36.1% with SC/Sß+ had raised BMI compared to Mississippi and national rates, 39.2 and 31%, respectively. The prevalence of children with raised BMI with SC/Sß+ did not differ from state and national rates, while children with SS/Sß° were half as likely as their Mississippi peers to have raised BMI. Haemoglobin levels were different among children with SCD who had low BMI (8.80 g/dL), average BMI (9.2 g/dL) and raised BMI (10.5 g/dL) (P < 0.001). CONCLUSIONS: Children with SCD evaluated at UMMC have similar rates of raised BMI compared to state and national norms. Children with raised BMI have higher mean haemoglobin levels compared to children with SCD with low or average BMI. IMPLICATIONS AND CONTRIBUTION: Historically, patients with SCD have been underweight and normal weight. Our paediatric and adolescent patients with SCD now have prevalence rates of raised BMI that approach state and national rates. Further work must be done to determine whether this reflects healthier children with SCD or raises concerns about life-style-related comorbidities.

The effect of stimulant medication on the learning of academic curricula in children with ADHD: A randomized crossover study.

OBJECTIVE: Evaluate whether stimulant medication improves acquisition of academic material in children with attention deficit hyperactivity disorder (ADHD) receiving small-group, content-area instruction in a classroom setting. METHOD: Participants were 173 children between the ages of 7 and 12 years old (77% male, 86% Hispanic) who met Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for ADHD and were participating in a therapeutic summer camp. The design was a triple-masked, within-subject, AB/BA crossover trial. Children completed two consecutive phases of daily, 25-min instruction in both (a) subject-area content (science, social studies) and (b) vocabulary. Each phase was a standard instructional unit lasting for 3 weeks. Teachers and aides taught the material to small groups in a summer classroom setting. Each child was randomized to be medicated with daily osmotic-release oral system methylphenidate (OROS-MPH) during either the first or second of the instructional phases, receiving placebo during the other. RESULTS: Medication had large, salutary, statistically significant effects on children's academic seatwork productivity and classroom behavior on every single day of the instructional period. However, there was no detectable effect of medication on learning the material taught during instruction: Children learned the same amount of subject-area and vocabulary content whether they were taking OROS-MPH or placebo during the instructional period. CONCLUSIONS: Acute effects of OROS-MPH on daily academic seatwork productivity and classroom behavior did not translate into improved learning of new academic material taught via small-group, evidence-based instruction. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Mixed-Method Examination of Latinx Teachers' Perceptions of Daily Behavioral Report Card Interventions to Support Students with ADHD.

Daily behavioral report cards (DRC) are an efficacious intervention for children with ADHD, yet there is little information on Latinx teachers' perceptions about ADHD and preferences related to behavioral treatment. The purpose of the current study was to examine the feasibility and acceptability of behavioral consultation with Latinx teachers and students, with a particular focus on the DRC. Participants (n = 23) included elementary school teachers (100% Hispanic/Latinx, 96% female) working with predominantly Hispanic/Latinx students. We leveraged a convergent, mixed-method design to evaluate feasibility, acceptability, as well as several potentially associated factors (i.e., perceptual, practical/logistical, individual, and cultural factors). Quantitative and qualitative measures and analyses were guided by the Consolidated Framework for Intervention Research. We found that Latinx teachers' Daily Report Card (DRC) completion rates (80%) were comparable to previous studies with predominantly non-Latinx white teachers and students. Quantitative indicators of acceptability were also similar to the prior literature. Few variables were associated with DRC completion rates, with the exception of teacher self-report of stress and satisfaction, which were both positively associated with completion rates. Qualitative findings expanded quantitative trends; thematic analyses revealed two overarching themes, that (1) teachers' attitudes toward behavioral interventions matter a great deal, and that (2) teachers' perceived behavioral control over DRC implementation depends a lot on the environment. Findings highlight the importance of stakeholders' perspectives, including teachers, in translating research to practice in real world settings.

Prevalence and Correlates of Attention-Deficit Hyperactivity Disorder in a Diverse, Treatment-Seeking Pediatric Overweight/Obesity Sample.

OBJECTIVE: Attention-deficit hyperactivity disorder (ADHD) and obesity are highly prevalent, impairing, and costly conditions, affecting about 10% of children each. Research indicates heightened prevalence of childhood obesity among youth with ADHD. However, more research is needed, examining comorbid ADHD among youth with overweight/obesity (OV/OB) from diverse demographic backgrounds and effects on medically relevant behaviors. The aim of the current study was to examine the prevalence of ADHD in a racially diverse sample of youth in a weight management clinic. Furthermore, we examined the effects of race, rurality, and ADHD on weight status and health behaviors in this under-researched population. METHOD: Participants included 1003 patients (Mage = 12.55; 58% female; 67% Black/African American; MBMI Z-Score = 2.54; 98.6% with obesity) in a pediatric weight management clinic serving a rural and urban/suburban area in the southern United States. Parent-reported demographics, ADHD diagnosis, and child health behaviors were recorded. RESULT: In total, 17.6% (n = 177) of the sample had an ADHD diagnosis. ADHD status interacted with race to predict standardized body mass index (BMIz), and rurality predicted higher BMIz. Children with comorbid ADHD had significantly more meals per day and fewer active days compared with children with OV/OB without ADHD. CONCLUSION: ADHD prevalence was higher in this diverse sample of children seeking obesity treatment (17.6%) compared with the prevalence nationally (9%-10%) and in other obesity samples. Comorbid ADHD was related to higher weight status among racial minority youth and increased engagement in unhealthy lifestyle behaviors often targeted in weight management treatment. It is critical to screen for ADHD in pediatric specialty clinics and assess healthy lifestyle behaviors.

Risk for substance use among adolescents at-risk for childhood victimization: The moderating role of ADHD.

BACKGROUND: Youth who are victimized by violence are at heightened risk for substance use (SU) during adolescence, a period characterized by elevated impulsivity and risk-taking behavior. This risk may be magnified by attention-deficit/hyperactivity disorder (ADHD). OBJECTIVE: To examine risk/protective factors for adolescent SU among adolescents at-risk for victimization and whether ADHD moderates these associations. PARTICIPANTS AND SETTING: Participants were 1058 caregiver-adolescent dyads in the U.S. who participated in the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). METHOD: Binary logistic regression analyses were conducted for each SU type. First-order effects of all variables were tested first and for each SU outcome, followed by tests of two-way interactions between ADHD group and each predictor, after controlling for first-order effects. RESULTS: More externalizing behavior (odds ratio [OR] = 1.38; 95 % confidence interval [CI]:1.12, 1.71) and less parental knowledge (OR = .75; 95 %CI: .60, .95) were associated with greater risk for subsequent tobacco use. Less positive peer affiliation was associated with greater risk for subsequent illicit SU (OR = .59; 95 %CI: .36, .96). More deviant peer affiliation were associated with greater risk for all forms of SU. ADHD moderated the association between deviant peer affiliation and marijuana use [b = .9, p < .05, 95 %CI: .03, 1.77), such that deviant peer affiliation was a significantly stronger predictor of marijuana use among adolescents with ADHD than those without. CONCLUSIONS: Findings suggest risk and protective factors for SU are largely consistent for adolescents at-risk for victimization with and without ADHD, but at-risk adolescents with ADHD may be more susceptible to deviant peer influences.

Leveraging Machine Learning to Identify Predictors of Receiving Psychosocial Treatment for Attention Deficit/Hyperactivity Disorder.

This study aimed to identify factors associated with receiving psychosocial treatment for ADHD in a nationally representative sample. Participants were 6630 youth with a parent-reported diagnosis of ADHD from the 2016-2017 National Survey of Children's Health. Machine learning analyses were performed to identify factors associated with receipt of psychosocial treatment for ADHD. We examined potentially associated factors in the broad categories of variables hypothesized to affect problem recognition (e.g., severity, mental health comorbidities); the decision to seek treatment; service selection (e.g., insurance coverage) and service use. We found that three machine learning models unanimously identified parent-reported ADHD severity (mild vs. moderate/severe) as the factor that best distinguishes between children who receive psychosocial treatment for ADHD and those who do not. Receive operating characteristic curve analysis revealed the following model performance: classification and regression tree analysis (area under the curve; AUC = .68); an ensemble model (AUC = .71); and a deep, multi-layer neural network (AUC = .72), as well as comparison to a logistic regression model (AUC = .69). Further, insurance coverage of mental/behavioral health needs emerged as a salient factor associated with the receipt of psychosocial treatment. Machine learning models identified risk and protective factors that predicted the receipt of psychosocial treatment for ADHD, such as ADHD severity and health insurance coverage.

Functional Outcomes of Young Adults with Childhood ADHD: A Latent Profile Analysis.

Adults with childhood attention-deficit hyperactivity disorder (ADHD) experience impairment in core functional domains (e.g., educational attainment, occupational status, social relationships, substance abuse, and criminal behavior), but it is currently unclear which impairments co-occur and whether subgroups experience differentiable patterns, none, or all aforementioned functional domains. Latent profile analysis (LPA) was used to characterize patterns of impairment. Data from the Pittsburgh ADHD Longitudinal Study were used. The 317 participants were 25 years old and had childhood ADHD. LPA characterized the variability across substance use (alcohol consumption, cigarette smoking, marijuana use), criminal behavior, peer impairment, educational attainment, maternal relationship, financial dependence, and sexual activity among young adults with childhood ADHD. Childhood predictors of profiles were examined, and ADHD profiles were compared to a matched comparison group without ADHD also followed longitudinally (n = 217). Five profiles were found: prototypic impairment group (54%), high binge-drinking group (17%), high marijuana use group (10%), high criminal activity group (3%), and high cross-domain impairment group (17%). All profiles were impaired compared to non-ADHD young adults. Childhood variables rarely significantly predicted profiles. Young adults with childhood ADHD have differentiable impairment patterns that vary based on substance use, criminal behavior, and number of clinically impaired domains. Nearly all young adult ADHD profiles were impaired in peer, educational, and financial domains, and there was not a nonimpaired ADHD profile. Use of specific substances was elevated among subgroups of, but not all, young adults with ADHD histories. Finally, the high cross-domain impairment profile was impaired in all domains.

Prospective Risk and Protective Factors for Juvenile Arrest Among Youth At Risk for Maltreatment.

This study aimed to prospectively identify ecological risk factors for juvenile arrest in a sample of youth at risk for maltreatment. Chi-Squared Automatic Interaction Detector analysis was performed with data from 592 youth from the Longitudinal Studies of Child Abuse and Neglect to identify the optimal combination of age 14 predictors of past-year arrest at age 16. Results extended previous research, which has identified being male, having more conduct disorder symptoms, suspension from school, perceived school importance, witnessing family violence, and having a jailed family member as key risk and protective factors for arrest by identifying important interactions among these risk factors. These interactions differentiate youth at the greatest risk of arrest, which, in this sample, were males with greater than two symptoms of conduct disorder who witnessed family violence. These findings suggest that longitudinal and multi-informant data could inform the refinement of actuarial risk assessments for juvenile arrest.

The Effects of Stimulant Medication and Training on Sports Competence Among Children With ADHD.

The current study examined the relative efficacy of behavioral sports training, medication, and their combination in improving sports competence among youth with attention deficit/hyperactivity disorder (ADHD). Participants were 73 youth (74% male; 81% Hispanic) between the ages of 5 and 12 diagnosed with Diagnostic and Statistical Manual of Mental Disorders (4th ed.) ADHD enrolled in a Summer Treatment Program (STP). The study consisted of a 2 (medication: methylphenidate, placebo) × 2 (sports training: instruction and practice, recreational play) between-groups design and was conducted over a 3-week period during the STP. Sports training was conducted with a novel sport, badminton, to limit previous sport knowledge and to differentiate it from concurrent sports training that occurred within the STP. Objective and subjective measures of sports skills, knowledge, and behavior were collected. Results indicated that, relative to recreational play, brief sports training improved observed and counselor-rated measures of sports competence including sports skills, knowledge, game awareness, effort, frustration, and enjoyment. During sports training, medication incrementally improved children's observed rule following behavior and counselor-rated sportsmanship relative to placebo. In the absence of sports training, medication improved behavior, effort, and sport knowledge. Training in sports skills and rules produced the largest magnitude effects on sports-related outcomes. Therefore, skills training, rather than medication alone, should be used in conjunction with behavioral intervention to teach sports to youth with ADHD. It is recommended that medication be used only as an adjunct to highly structured sports skills training for youth who display high rates of negative behavior during sports activities.

Rates of cerebral protein synthesis in primary visual cortex during sleep-dependent memory consolidation, a study in human subjects.

If protein synthesis during sleep is required for sleep-dependent memory consolidation, we might expect rates of cerebral protein synthesis (rCPS) to increase during sleep in the local brain circuits that support performance on a particular task following training on that task. To measure circuit-specific brain protein synthesis during a daytime nap opportunity, we used the L-[1-(11)C]leucine positron emission tomography (PET) method with simultaneous polysomnography. We trained subjects on the visual texture discrimination task (TDT). This was followed by a nap opportunity during the PET scan, and we retested them later in the day after the scan. The TDT is considered retinotopically specific, so we hypothesized that higher rCPS in primary visual cortex would be observed in the trained hemisphere compared to the untrained hemisphere in subjects who were randomized to a sleep condition. Our results indicate that the changes in rCPS in primary visual cortex depended on whether subjects were in the wakefulness or sleep condition but were independent of the side of the visual field trained. That is, only in the subjects randomized to sleep, rCPS in the right primary visual cortex was higher than the left regardless of side trained. Other brain regions examined were not so affected. In the subjects who slept, performance on the TDT improved similarly regardless of the side trained. Results indicate a regionally selective and sleep-dependent effect that occurs with improved performance on the TDT.

Direct and Indirect Pathways From Adverse Childhood Experiences to High School Dropout Among High-Risk Adolescents.

Adverse childhood experiences (ACEs) are associated with an increased risk for school dropout. This study examined pathways from childhood adversity to school dropout through academic, behavioral, emotional, and social pathways. Data were collected prospectively from 728 adolescents and their caregivers who participated in the Longitudinal Studies of Child Abuse and Neglect and from child protective services records. Path analyses revealed a direct association between ACEs and dropout, as well as indirect effects through poor reading achievement and elevated externalizing problems. ACEs were associated with elevated internalizing problems, which were negatively associated with dropout. However, ACEs were not associated with peer influences. Implications of the identified mechanisms in the ACEs and school dropout association for future preventive interventions are discussed.

Improving homework performance among children with ADHD: A randomized clinical trial.

OBJECTIVE: Evidence indicates that children with Attention Deficit Hyperactivity Disorder (ADHD) experience acute and prolonged academic impairment and underachievement including marked difficulty with completing homework. This study is the first to examine the effects of behavioral, psychostimulant, and combined treatments on homework problems, which have been shown to predict academic performance longitudinally. METHOD: Children with ADHD (ages 5-12, N = 75, 71% male, 83% Hispanic/Latino) and their families were randomly assigned to either behavioral treatment (homework-focused parent training and a daily report card; BPT + DRC) or a waitlist control group. Children also participated in a concurrent psychostimulant crossover trial conducted in a summer treatment program. Children's objective homework completion and accuracy were measured as well as parent-reported child homework behaviors and parenting skills. RESULTS: BPT + DRC had large effects on objective measures of homework completion and accuracy (Cohen's ds from 1.40 to 2.21, ps < .001). Other findings, including unimodal medication and incremental combined treatment benefits, were not significant. CONCLUSIONS: Behavioral treatment focused on homework problems results in clear benefits for children's homework completion and accuracy (the difference between passing and failing, on average), whereas long-acting stimulant medication resulted in limited and largely nonsignificant acute effects on homework performance. (PsycINFO Database Record

Parent Management of Organization, Time Management, and Planning Deficits among Adolescents with ADHD.

Organization, Time Management, and Planning (OTP) problems are a key mechanism of academic failure for adolescents with ADHD. Parents may be well positioned to promote remediation of these deficits; yet, almost nothing is known about OTP management behaviors among parents of middle and high school students with ADHD. In a sample of 299 well-diagnosed adolescents with ADHD, a measure of parental OTP management was psychometrically validated. Latent Class Analysis was conducted to detect distinct patterns of parental OTP management and yielded four unique classes: Parental Control (18.7 %), Parent-Teen Collaboration (20.4 %), Homework Assistance (20.4 %), and Uninvolved (40.5 %). Logistic Regression analyses indicated that maladaptive parental OTP strategies were related to higher levels of parent and adolescent psychopathology. Parental OTP management did not relate to current adolescent OTP skills or GPA, indicating that parents did not select OTP management strategies in immediate response to adolescent functioning. Implications for parent-directed intervention are discussed.

A PILOT STUDY ON THE ENCODING OF A PERCEPTUAL LEARNING TASK FOLLOWING SLEEP DEPRIVATION.

Memory encoding sometimes must occur during a period of sleep deprivation. The question was whether one night of sleep deprivation inhibits encoding on a perceptual learning task (the texture discrimination task). The sample was 18 human participants (M age=22.1 yr., SEM=0.5; 8 men). The participants were randomized to a sleep deprivation or sleep control condition and, after the manipulation, were given two administrations of the texture discrimination task. All participants were given an opportunity for a 90 min. nap between the two administrations. Performance was measured by the interpolated stimulus-to-mask-onset asynchrony (i.e., the inter-stimulus interval), at which the percentage of correct responses for the stimuli in the participant's peripheral vision fell below 80%. Offline consolidation was defined as a decrease in this index between the two administrations. Participants who were sleep deprived prior to encoding exhibited similar offline consolidation (M=-5.3 msec., SEM=2.3) compared to participants who were not sleep deprived prior to encoding (M=-6.2 msec., SEM=3.9); the two-way interaction between time and condition was not significant. In light of reports in the literature, these results indicate encoding following sleep deprivation may be influenced by both the type of task encoded and the brain regions involved in memory processing.

The lipid kinase PI4KIIIß is highly expressed in breast tumors and activates Akt in cooperation with Rab11a.

Emerging evidence now implicates phosphatidylinositol 4-kinases (PI4K), enzymes that generate PI(4)P from phosphatidylinositol (PtdIns), in cancer. In this study, we investigate the role of PI4KIIIß, one of four mammalian PI4Ks, in breast cancer. Although PI4KIIIß protein levels are low in normal breast tissue, we find that approximately 20% of primary human breast tumors overexpress it. Expression of PI4KIIIß in breast carcinoma cells leads to increased Akt activation, dependent on increased PI(3,4,5)P3 production. However, a kinase-inactive version of PI4KIIIß also led to increased Akt activation, and no changes in PI(4)P or PI(4,5)P2 lipid abundance were detected in the PI4KIIIß-overexpressing cells. This implies that PI4KIIIß regulates PI(3,4,5)P3 and Akt independent of PI(4)P production. We find that the PI4KIIIß-binding protein, Rab11a, a small GTPase that regulates endosomal recycling, is involved in PI4KIIIß-mediated activation of Akt, as RNAi depletion of Rab11a impairs Akt activation. Furthermore, ectopic PI4KIIIß expression alters cellular Rab11a distribution and enhances recruitment of PI4KIIIß and Rab11a to recycling endosomes. This work suggests that PI4KIIIß affects PI3K/Akt signaling through Rab11a and endosomal trafficking, independent of its lipid kinase activity. Thus, PI4KIIIß likely plays a role in breast oncogenesis and that cooperation between Rab11a and PI4KIIIß represents a novel Akt activation pathway.

Mapping the academic problem behaviors of adolescents with ADHD.

This study possessed 2 aims: (a) to develop and validate a clinician-friendly measure of academic problem behavior that is relevant to the assessment of adolescents with attention deficit/hyperactivity disorder (ADHD) and (b) to better understand the cross-situational expression of academic problem behaviors displayed by these youth. Within a sample of 324 adolescents with the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision diagnosed ADHD (age M = 13.07, SD = 1.47), parent, teacher, and adolescent self-report versions of the Adolescent Academic Problems Checklist (AAPC) were administered and compared. Item prevalence rates, factorial validity, interrater agreement, internal consistency, and concurrent validity were evaluated. Findings indicated the value of the parent and teacher AAPC as a psychometrically valid measure of academic problems in adolescents with ADHD. Parents and teachers offered unique perspectives on the academic functioning of adolescents with ADHD, indicating the complementary roles of these informants in the assessment process. According to parent and teacher reports, adolescents with ADHD displayed problematic academic behaviors in multiple daily tasks, with time management and planning deficits appearing most pervasive. Adolescents with ADHD display heterogeneous academic problems that warrant detailed assessment prior to treatment. As a result, the AAPC may be a useful tool for clinicians and school staff conducting targeted assessments with these youth.

FiloDetect: automatic detection of filopodia from fluorescence microscopy images.

BACKGROUND: Filopodia are small cellular projections that help cells to move through and sense their environment. Filopodia play crucial roles in processes such as development and wound-healing. Also, increases in filopodia number or size are characteristic of many invasive cancers and are correlated with increased rates of metastasis in mouse experiments. Thus, one possible route to developing anti-metastatic therapies is to target factors that influence the filopodia system. Filopodia can be detected by eye using confocal fluorescence microscopy, and they can be manually annotated in images to quantify filopodia parameters. Although this approach is accurate, it is slow, tedious and not entirely objective. Manual detection is a significant barrier to the discovery and quantification of new factors that influence the filopodia system. RESULTS: Here, we present FiloDetect, an automated tool for detecting, counting and measuring the length of filopodia in fluorescence microscopy images. The method first segments the cell from the background, using a modified triangle threshold method, and then extracts the filopodia using a series of morphological operations. We verified the accuracy of FiloDetect on Rat2 and B16F1 cell images from three different labs, showing that per-cell filopodia counts and length estimates are highly correlated with the manual annotations. We then used FiloDetect to assess the role of a lipid kinase on filopodia production in breast cancer cells. Experimental results show that PI4KIII ß expression leads to an increase in filopodia number and length, suggesting that PI4KIII ß is involved in driving filopodia production. CONCLUSION: FiloDetect provides accurate and objective quantification of filopodia in microscopy images, and will enable large scale comparative studies to assess the effects of different genetic and chemical perturbations on filopodia production in different cell types, including cancer cell lines.

Rethinking mobile delivery: using Quick Response codes to access information at the point of need.

This article covers the use of Quick Response (QR) codes to provide instant mobile access to information, digital collections, educational offerings, library website, subject guides, text messages, videos, and library personnel. The array of uses and the value of using QR codes to push customized information to patrons are explained. A case is developed for using QR codes for mobile delivery of customized information to patrons. Applications in use at the Libraries of the University of Utah will be reviewed to provide readers with ideas for use in their library.

Robust patterns in the stochastic organization of filopodia.

BACKGROUND: Filopodia are actin-based cellular projections that have a critical role in initiating and sustaining directional migration in vertebrate cells. Filopodia are highly dynamic structures that show a rich diversity in appearance and behavior. While there are several mathematical models of filopodia initiation and growth, testing the capacity of these theoretical models in predicting empirical behavior has been hampered by a surprising shortage of quantitative data related to filopodia. Neither is it clear how quantitatively robust the cellular filopodial network is and how perturbations alter it. RESULTS: We have measured the length and interfilopodial separation distances of several thousand filopodia in the rodent cell line Rat2 and measured these parameters in response to genetic, chemical and physical perturbation. Our work shows that length and separation distance have a lognormal pattern distribution over their entire detection range (0.4 µm to 50 µm). CONCLUSIONS: We find that the lognormal distribution of length and separation is robust and highly resistant to perturbation. We also find that length and separation are independent variables. Most importantly, our empirical data is not entirely in agreement with predictions made based on existing theoretical models and that filopodial size and separation are an order of magnitude larger than what existing models suggest.