This book takes a fresh look at the popular and well-established method of maximum likelihood for statistical estimation and inference. It begins with an intuitive introduction to the concepts and ...background of likelihood, and moves through to the latest developments in maximum likelihood methodology, including general latent variable models and new material for the practical implementation of integrated likelihood using the free ADMB software. Fundamental issues of statistical inference are also examined, with a presentation of some of the philosophical debates underlying the choice of statistical paradigm.Key features:Provides an accessible introduction to pragmatic maximum likelihood modelling.Covers more advanced topics, including general forms of latent variable models (including non-linear and non-normal mixed-effects and state-space models) and the use of maximum likelihood variants, such as estimating equations, conditional likelihood, restricted likelihood and integrated likelihood.Adopts a practical approach, with a focus on providing the relevant tools required by researchers and practitioners who collect and analyze real data.Presents numerous examples and case studies across a wide range of applications including medicine, biology and ecology.Features applications from a range of disciplines, with implementation in R, SAS and/or ADMB.Provides all program code and software extensions on a supporting website.Confines supporting theory to the final chapters to maintain a readable and pragmatic focus of the preceding chapters. This book is not just an accessible and practical text about maximum likelihood, it is a comprehensive guide to modern maximum likelihood estimation and inference. It will be of interest to readers of all levels, from novice to expert. It will be of great benefit to researchers, and to students of statistics from senior undergraduate to graduate level. For use as a course text, exercises are provided at the end of each chapter.
Transgender and nonbinary children and adolescents bear a disproportionate level of poor health, and adverse developmental and academic outcomes compared to their cisgender peers. In this article, I ...review evidence from recent research on minority stress and resilience among trans youth and advocate for two additional domains to be included when studying the experiences of trans youth from a minority stress perspective. I describe the variability across sexual‐minority and gender‐minority youth in experiences of minority stress across and within contexts. I advocate for explicit attention in minority stress models with gender‐minority youth to the domains of (a) intrapersonal and interpersonal gender dysphoria, and (b) access and use of affirmative and comprehensive health care.
Studies of adults who experienced sexual orientation change efforts (SOCE) have documented a range of health risks. To date, there is little research on SOCE among adolescents and no known studies of ...parents' role related to SOCE with adolescents. In a cross-sectional study of 245 LGBT White and Latino young adults (ages 21-25), we measured parent-initiated SOCE during adolescence and its relationship to mental health and adjustment in young adulthood. Measures include being sent to therapists and religious leaders for conversion interventions as well as parental/caregiver efforts to change their child's sexual orientation during adolescence. Attempts by parents/caregivers and being sent to therapists and religious leaders for conversion interventions were associated with depression, suicidal thoughts, suicidal attempts, less educational attainment, and less weekly income. Associations between SOCE, health, and adjustment were much stronger and more frequent for those reporting both attempts by parents and being sent to therapists and religious leaders, underscoring the need for parental education and guidance.
Abstract Students’ perceptions of their school climates are associated with psychosocial and academic adjustment. The present study examined the role of school strategies to promote safety in ...predicting students’ perceptions of safety for gender nonconforming peers among 1415 students in 28 high schools. Using multilevel modeling techniques, we examined student- and school-level effects on students’ perceptions of safety for gender nonconforming peers. We found that older students, bisexual youth, Latino youth, and youth who experienced school violence perceived their gender nonconforming male peers to be less safe. Similarly, we found that older students and students who experienced school violence and harassment due to gender nonconformity perceived their gender nonconforming female peers to be less safe. At the school-level, we found that when schools included lesbian, gay, bisexual, transgender, and queer (LGBTQ) issues in the curriculum and had a Gay-Straight Alliance, students perceived their schools as safer for gender nonconforming male peers.
Floating mats of vegetation serve to transfer biomass, nutrients and energy across marine habitats and alter the spectral properties of the sea surface. Here, spectral measurements from the airborne ...Portable Remote Imaging Spectrometer (PRISM) imagery at 1-m resolution and experimental mesocosms were used to assess the hyperspectral properties of the macroalgae Sargassum and aggregations of the seagrass Syringodium filiforme wrack in Greater Florida Bay. A simple Normalized Difference Vegetative Index (NDVI) effectively discriminated the presence of vegetation floating on the sea surface. The Sargassum Index derived from reflectance ratios at 650 and 630nm was used to effectively discriminate Sargassum from Syringodium wrack. Mesocosm spectral measurements revealed an initial lowering of wrack reflectance over the first 3days followed by a subsequent increase in reflectance over the next 8days. The age of the wrack estimated from 2 to 5days was best characterized using narrowband indices of the water absorption feature at 930 and 990nm potentially from increasing water content in wrack leaves over time. Hyperspectral imagery (<10nm) was necessary to differentiate between these two types of floating vegetation and assess age of the wrack. PRISM imagery revealed seagrass wrack organized in 5–35m spaced windrows caused by Langmuir circulation. Wrack was only detectable at 60mpixel resolution when densities were high and individual windrows were in close proximity.
•Different types of floating vegetation can be assessed with hyperspectral imagery.•Organized windrows of floating seagrass wrack revealed with airborne PRISM imagery.•Sargassum Index effectively discriminated Sargassum from Syringodium wrack.•Age of seagrass wrack could be assessed with increasing water absorption at 990nm.
The study of gold nanoclusters (AuNCs) has seen much interest in recent history due to their unique fluorescence properties and environmentally friendly synthesis method using proteins as a growth ...scaffold. The differences in the physicochemical properties of lysozyme encapsulated AuNCs in comparison to natural lysozyme are characterised in order to determine the effects AuNCs have on natural protein behaviour. The hydrodynamic radius (dynamic light scattering), light absorbance (UV-Vis), electrophoretic mobility, relative density, dynamic viscosity, adsorption (quartz crystal microbalance) and circular dichroism (CD) characteristics of the molecules were studied. It was found that lysozyme forms small dimer/trimer aggregates upon the synthesis of AuNCs within the protein. The diameter of Ly-AuNCs was found to be 8.0 nm across a pH range of 2-11 indicating dimer formation, but larger aggregates with diameters >20 nm were formed between pH 3 and 6. The formation of larger aggregates limits the use of Ly-AuNCs as a fluorescent probe in this pH range. A large shift in the protein's isoelectric point was also observed, shifting from 11.0 to 4.0 upon AuNC synthesis. This resulted in major changes to the adsorption characteristics of lysozyme, observed using a QCM. A monolayer of 8 nm was seen for Ly-AuNCs at pH 4, offering further evidence that the proteins form small aggregates, unlike the natural monomer form of lysozyme. The adsorption of Ly-AuNCs was seen to decrease as pH was increased; this is in major contrast to the lysozyme adsorption behaviour. A decrease in the α-helix content was observed from 25% in natural lysozyme to 1% in Ly-AuNCs. This coincided with an increase in the β-sheet content after AuNC synthesis indicating that the natural structure of lysozyme was lost. The formation of protein dimers, the change in the protein surface charge from positive to negative, and secondary structure alteration caused by the AuNC synthesis must be considered before attempting to utilise Ly-AuNCs as
in vivo
probes.
Protein encapsulated gold nanocluster synthesis within lysozyme proteins results in major changes to the native lysozyme's physicochemical characteristics.
Viral infection can dramatically alter a cell's transcriptome. However, these changes have mostly been studied by bulk measurements on many cells. Here we use single-cell mRNA sequencing to examine ...the transcriptional consequences of influenza virus infection. We find extremely wide cell-to-cell variation in the productivity of viral transcription - viral transcripts comprise less than a percent of total mRNA in many infected cells, but a few cells derive over half their mRNA from virus. Some infected cells fail to express at least one viral gene, but this gene absence only partially explains variation in viral transcriptional load. Despite variation in viral load, the relative abundances of viral mRNAs are fairly consistent across infected cells. Activation of innate immune pathways is rare, but some cellular genes co-vary in abundance with the amount of viral mRNA. Overall, our results highlight the complexity of viral infection at the level of single cells.
School-based victimization is associated with poorer developmental, academic, and health outcomes. This meta-analytic review compared the mean levels of school-based victimization experienced by ...sexual minority youth to those of heterosexual youth, and examined moderators of this difference. Results from 18 independent studies (N = 56,752 participants) suggest that sexual minority youth experience moderately higher levels of school-based victimization compared to heterosexual youth (d = 0.33). This effect varied by two study characteristics: the average effect size increased over time and was larger in studies that had a greater proportion of male participants. Results highlight the need for future research on school-based victimization to include measures of sexual orientation and for interventions to include a component that addresses sexual orientation.
The contiguous United States (CONUS), especially the West, faces challenges of increasing water stress and uncertain impacts of climate change. The historical information of surface water body ...distribution, variation, and multidecadal trends documented in remote-sensing images can aid in water-resource planning and management, yet is not well explored. Here, we detected open-surface water bodies in all Landsat 5, 7, and 8 images (∼370,000 images, >200 TB) of the CONUS and generated 30-meter annual water body frequency maps for 1984–2016. We analyzed the interannual variations and trends of year-long water body area, examined the impacts of climatic and anthropogenic drivers on water body area dynamics, and explored the relationships between water body area and land water storage (LWS). Generally, the western half of the United States is prone to water stress, with small water body area and large interannual variability. During 1984–2016, water-poor regions of the Southwest and Northwest had decreasing trends in water body area, while water-rich regions of the Southeast and far north Great Plains had increasing trends. These divergent trends,mainly driven by climate, enlarged water-resource gaps and are likely to continue according to climate projections. Water body area change is a good indicator of LWS dynamics in 58% of the CONUS. Following the 2012 prolonged drought, LWS in California and the southern Great Plains had a larger decrease than surface water body area, likely caused by massive groundwater withdrawals. Our findings provide valuable information for surface water-resource planning and management across the CONUS.
In 15 participants with hemophilia A treated with a single infusion of AAV5 vector containing the factor VIII gene, 7 who received 6×10
13
vector genomes per kilogram had a median factor VIII level ...of 20 IU per deciliter, and 6 who received 4×10
13
vg per kilogram had a median level of 13 IU per deciliter. Factor VIII levels decreased in years 2 and 3 of follow-up, but the median annualized rate of bleeding events among these 13 participants remained zero.
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