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Pediatric brain tumors are the leading cause of cancer-related death in children in the United States and contribute a disproportionate number of potential years of life lost compared to adult cancers. Moreover, survivors frequently suffer long-term side effects, including secondary cancers. The Children’s Brain Tumor Network (CBTN) is a multi-institutional international clinical research consortium created to advance therapeutic development through the collection and rapid distribution of biospecimens and data via open-science research platforms for real-time access and use by the global research community. The CBTN’s 32 member institutions utilize a shared regulatory governance architecture at the Children’s Hospital of Philadelphia to accelerate and maximize the use of biospecimens and data. As of August 2022, CBTN has enrolled over 4,700 subjects, over 1,500 parents, and collected over 65,000 biospecimen aliquots for research. Additionally, over 80 preclinical models have been developed from collected tumors. Multi-omic data for over 1,000 tumors and germline material is currently available with data generation for > 5,000 samples underway. To our knowledge, CBTN provides the largest open-access pediatric brain tumor multi-omic dataset annotated with longitudinal clinical and outcome data, imaging, associated biospecimens, child-parent genomic pedigrees, andin vivoandin vitropreclinical models. Empowered by NIH-supported platforms such as the Kids First Data Resource and the Childhood Cancer Data Initiative, the CBTN continues to expand the resources needed for scientists to accelerate translational impact for improved outcomes and quality of life for children with brain and spinal cord tumors.

Objectives Huntington’s disease (HD) is a neurodegenerative disease in which cognitive and behavioural symptoms impair the performance of instrumental activities of daily living, including the handling of finances. We sought to determine the prevalence of financial dysfunction in HD, and the demographic and clinical predictors of such impairments. Methods We analysed longitudinal data for pre-manifest gene carriers and HD patients from the Enroll-HD dataset. Financial dysfunction was determined by finance-related items in the Total Functional Capacity (TFC) and Functional Assessment (FA) scales. A binary logistical regression model was used to investigate the predictive value of demographic and clinical factors for the development of financial dysfunction. Results Financial impairment was found to be common in HD gene carriers, and over half required financial assistance within 5 years from diagnosis. Cognitive impairment, apathy, unemployment and disease severity predicted financial dysfunction in manifest patients. For pre-manifest patients, the predictors were proximity to disease onset and depression. Conclusions Loss of financial autonomy is common in HD, and cognitive and psychiatric factors are important in its development. Clinicians must be vigilant to identify patients that may be vulnerable to financial exploitation.

OBJECTIVES: Insight is an important predictor of quality of life in Huntington's disease and other neurodegenerative conditions. However, estimating insight with traditional methods such as questionnaires is challenging and subjected to limitations. This cross-sectional study experimentally quantified metacognitive insight into cognitive performance in Huntington's disease gene carriers. METHODS: We dissociated perceptual decision-making performance and metacognitive insight into performance in healthy controls (n=29), premanifest (n=19) and early-manifest (n=10) Huntington's disease gene carriers. Insight was operationalised as the degree to which a participant's confidence in their performance was informative of their actual performance (metacognitive efficiency) and estimated using a computational model (HMeta-d'). RESULTS: We found that premanifest and early-manifest Huntington's disease gene carriers were impaired in making perceptual decisions compared with controls. Gene carriers required more evidence in favour of the correct choice to achieve similar performance and perceptual impairments were increased in those with manifest disease. Surprisingly, despite marked perceptual impairments, Huntington's disease gene carriers retained metacognitive insight into their perceptual performance. This was the case after controlling for confounding variables and regardless of disease stage. CONCLUSION: We report for the first time a dissociation between impaired cognition and intact metacognition (trial-by-trial insight) in the early stages of a neurodegenerative disease. This unexpected finding contrasts with the prevailing assumption that cognitive deficits are associated with impaired insight. Future studies should investigate how intact metacognitive insight could be used by some early Huntington's disease gene carriers to positively impact their quality of life.

Huntington's disease (HD) is an inherited neurodegenerative disease characterised by neuropsychiatric symptoms, a movement disorder (most commonly choreiform) and progressive cognitive impairment. The diagnosis is usually confirmed through identification of an increased CAG repeat length in the huntingtin gene in a patient with clinical features of the condition. Though diagnosis is usually straightforward, unusual presentations can occur, and it can be difficult to know when someone has transitioned from being an asymptomatic carrier into the disease state. This has become increasingly important recently, with several putative disease-modifying therapies entering trials. A growing number of conditions can mimic HD, including rare genetic causes, which must be considered in the event of a negative HD genetic test. Patients are best managed in specialist multidisciplinary clinics, including when considering genetic testing. Current treatments are symptomatic, and largely directed at the chorea and neurobehavioural problems, although supporting trial evidence for these is often limited.

Huntington's disease starts slowly and progresses over a 15-20 year period. Motor changes begin subtly, often going unnoticed by patients although they are typically visible to those close to them. At this point, it is the early non-motor problems of HD that arguably cause the most functional impairment. Approximately 65% of gene carriers will experience a reduction in their occupational level, and just under half will feel unable to manage their finances independently before a clinical diagnosis is made. Understanding what drives this impairment in activities of daily living is the key to helping people with HD to live more independently for longer, especially in early disease. Early cognitive decline is likely to play a contributory factor although few studies have looked directly at this relationship. Recently, it has been shown that along with the well documented dysexecutive syndrome seen in HD, changes in social cognition and decision-making are more common than previously thought. Furthermore, some of the early neuropathological and neurochemical changes seen in HD disrupt networks known to be involved in social functioning. In this review, we explore how HD changes the way individuals interact in a social world. Specifically, we summarise the literature on both classical and social decision-making (value-based decision-making in a social context) along with studies of theory of mind, empathy, alexithymia, and emotion recognition in HD. The literature specific to HD is discussed and supported by evidence from similar neurodegenerative disorders and healthy individuals to propose future directions and potential therapeutic avenues to be explored.

Supplemental material, sj-docx-1-jop-10.1177_02698811211069113 for LSD and creativity: Increased novelty and symbolic thinking, decreased utility and convergent thinking by Isabel Wie��ner, Marcelo Falchi, Lucas Oliveira Maia, Dimitri Daldegan-Bueno, Fernanda Palhano-Fontes, Natasha L Mason, Johannes G Ramaekers, Madeleine E Gross, Jonathan W Schooler, Amanda Feilding, Sidarta Ribeiro, Draulio B Araujo and Lu��s Fernando T��foli in Journal of Psychopharmacology

Supplemental material, sj-docx-1-jop-10.1177_02698811211069113 for LSD and creativity: Increased novelty and symbolic thinking, decreased utility and convergent thinking by Isabel Wie��ner, Marcelo Falchi, Lucas Oliveira Maia, Dimitri Daldegan-Bueno, Fernanda Palhano-Fontes, Natasha L Mason, Johannes G Ramaekers, Madeleine E Gross, Jonathan W Schooler, Amanda Feilding, Sidarta Ribeiro, Draulio B Araujo and Lu��s Fernando T��foli in Journal of Psychopharmacology

Clinical research into serotonergic psychedelics is expanding rapidly, showing promising efficacy across myriad disorders. Resting-state functional magnetic resonance imaging (rs-fMRI) is a commonly used strategy to identify psychedelic-induced changes in neural pathways in clinical and healthy populations. Here we, a large group of psychedelic imaging researchers, review the 42 research articles published to date, based on the 17 unique studies evaluating psychedelic effects on rs-fMRI, focusing on methodological variation. Prominently, we observe that nearly all studies vary in data processing and analysis methodology, two datasets are the foundation of over half of the published literature, and there is lexical ambiguity in common outcome metric terminology. We offer guidelines for future studies that encourage coherence in the field. Psychedelic rs-fMRI will benefit from the development of novel methods that expand our understanding of the brain mechanisms mediating its intriguing effects; yet, this field is at a crossroads where we must also consider the critical importance of consistency and replicability to effectively converge on stable representations of the neural effects of psychedelics.

Additional file 1: Figure S1. Representative agarose gel electrophoresis image of PCR amplified products of the mpsp fragment from acquisition- and transmission-fed calf blood samples. Acquisition-fed calf 1697 at 63 dpi and transmission-fed calves 1718, 1726, and 1727 at 14 dpi. POS; T. orientalis blood stabilate positive control, NEG; no template control.

Additional file 1. Appendix A: Quality of health economic studies framework.

Additional file 2: Poster. Methodology to develop guidelines for the management of patients with CLN2 disease.

Additional file 2. Appendix B: CHEERS checklist of items studies should include when reporting economic evaluation of health interventions.

Additional file 1: Appendices. Appendices 1–9.

Additional file 3. Quality of health economic studies framework.

OBJECTIVE: To assess the claim that Parkinson's disease (PD) specifically reduces religiosity religious faith and spirituality. METHODS: A longitudinal case-control study over 12 months of spirituality in 42 patients with idiopathic PD and 39 disease controls matched for age, gender, educational attainment and disability. There was no selection on grounds of religious affiliation. Participants were assessed on the Beck Depression Inventory, Medical Outcomes Score (MOS), cognitive tests including Paired Associate Learning [PAL], One Touch Stocking [OTS]) and Stroop test. Tests of spirituality were the Brief Multidimensional Measure of Religiousness and Spirituality questionnaire (BMMRS), a Mystical Experiences Questionnaire (MEQ), and the Rivermead Life Goals Score, supplemented by qualitative interview methods. RESULTS: Over one year, as expected, mobility and cognition declined in the PD group. However, there was no significant change in scores of religiosity and spirituality scores in this group. Likewise, there were no subjective reports of a decrease of interest in religious faith or spirituality, although anecdotal accounts of decreasing mobility, loss of driving ability, increasing emotional lability and tiredness meant reduced participation in some religious and spiritual practices. However, over one year there was a significant fall in controls' religiosity score due mainly to a fall in 'religious practices' with no clear underlying reason. CONCLUSIONS: Compared to non-neurological patients with similar disability, Parkinson's disease is not associated with a decline in religious faith or spirituality. Declining mobility and cognition in Parkinson's disease does not lead to diminished religiosity.

Huntington’s Disease (HD) is an autosomal dominant condition that typically presents in midlife with a combination of motor, cognitive and psychiatric problems along with sleep and metabolic abnormalities. It runs a clinical course over 15-20 years leading to death as patients become demented and bed bound. There are currently no proven disease modifying therapies for HD. While the recent work with anti-sense therapies (ASO) against huntingtin has generated much excitement they are yet to demonstrate a measurable change in disease progression. Furthermore, given they promise to “modify” and not “cure” HD patients we will still require adjunct symptomatic treatments, potentially for longer periods of time. Symptomatic therapies for HD do exist and are widely used for treating the chorea and some of the psychiatric aspects of the condition although the extent to which they work is variable1 and many experience significant side effects with them. Therefore, there is still a need to develop better symptomatic therapies, ideally with single drugs that can help treat more than one sign and symptom of this condition.

UNLABELLED: Huntington's disease (HD) is a hereditary disorder that typically manifests in adulthood with a combination of motor, cognitive and psychiatric problems. The pathology is caused by a mutation in the huntingtin gene which results in the production of an abnormal protein, mutant huntingtin (mHtt). This protein is ubiquitously expressed and known to confer toxicity to multiple cell types. We have recently reported that HD brains are also characterised by vascular abnormalities, which include changes in blood vessel density/diameter as well as increased blood-brain barrier (BBB) leakage. OBJECTIVES: Seeking to elucidate the origin of these vascular and BBB abnormalities, we studied platelets that are known to play a role in maintaining the integrity of the vasculature and thrombotic pathways linked to this, given they surprisingly contain the highest concentration of mHtt of all blood cells. METHODS: We assessed the functional status of platelets by performing ELISA, western blot and RNA sequencing in a cohort of 71 patients and 68 age- and sex-matched healthy control subjects. We further performed haemostasis and platelet depletion tests in the R6/2 HD mouse model. RESULTS: Our findings indicate that the platelets in HD are dysfunctional with respect to the release of angiogenic factors and functions including thrombosis, angiogenesis and vascular haemostasis. CONCLUSION: Taken together, our results provide a better understanding for the impact of mHtt on platelet function.

NOAA Technical Memorandum NOS NCCOS 267

Supplemental Material for Cardiopulmonary remodeling in fattened beef cattle: a naturally occurring large animal model of obesity-associated pulmonary hypertension with left heart disease by Greta M. Krafsur, Joseph M. Neary, Franklyn Garry, Timothy Holt, Daniel H. Gould, Gary L. Mason, Milton G. Thomas, R. Mark Enns, Rubin M. Tuder, Michael P. Heaton, R. Dale Brown and Kurt R. Stenmark in Pulmonary Circulation

NOAA Technical Memorandum NOS NCCOS 261

NOAA Technical Memorandum NOS NCCOS ; 260

The production of extracellular vesicles (EV) is a ubiquitous feature of eukaryotic cells but pathological events can affect their formation and constituents. We sought to characterize the nature, profile and protein signature of EV in the plasma of Parkinson's disease (PD) patients and how they correlate to clinical measures of the disease. EV were initially collected from cohorts of PD (n = 60; Controls, n = 37) and Huntington's disease (HD) patients (Pre-manifest, n = 11; manifest, n = 52; Controls, n = 55) - for comparative purposes in individuals with another chronic neurodegenerative condition - and exhaustively analyzed using flow cytometry, electron microscopy and proteomics. We then collected 42 samples from an additional independent cohort of PD patients to confirm our initial results. Through a series of iterative steps, we optimized an approach for defining the EV signature in PD. We found that the number of EV derived specifically from erythrocytes segregated with UPDRS scores corresponding to different disease stages. Proteomic analysis further revealed that there is a specific signature of proteins that could reliably differentiate control subjects from mild and moderate PD patients. Taken together, we have developed/identified an EV blood-based assay that has the potential to be used as a biomarker for PD.

The production and release of extracellular vesicles (EV) is a property shared by all eukaryotic cells and a phenomenon frequently exacerbated in pathological conditions. The protein cargo of EV, their cell type signature and availability in bodily fluids make them particularly appealing as biomarkers. We recently demonstrated that platelets, among all types of blood cells, contain the highest concentrations of the mutant huntingtin protein (mHtt)-the genetic product of Huntington's disease (HD), a neurodegenerative disorder which manifests in adulthood with a complex combination of motor, cognitive and psychiatric deficits. Herein, we used a cohort of 59 HD patients at all stages of the disease, including individuals in pre-manifest stages, and 54 healthy age- and sex-matched controls, to evaluate the potential of EV derived from platelets as a biomarker. We found that platelets of pre-manifest and manifest HD patients do not release more EV even if they are activated. Importantly, mHtt was not found within EV derived from platelets, despite them containing high levels of this protein. Correlation analyses also failed to reveal an association between the number of platelet-derived EV and the age of the patients, the number of CAG repeats, the Unified Huntington Disease Rating Scale total motor score, the Total Functional Capacity score or the Burden of Disease score. Our data would, therefore, suggest that EV derived from platelets with HD is not a valuable biomarker in HD.

NOAA Technical Memorandum NOS NCCOS ; 100

As part of the NOAA Coral Reef Conservation Program (CRCP) jurisdictional priority gathering, local agencies in Guam identified Cocos Lagoon as an area potentially impacted by land-based sources of pollution. The US Coast Guard operated a Long Range Navigation (LORAN) station on Cocos Island at the southern end of Cocos Lagoon from 1944 to 1963. Disposal of materials from the operation of the station are suspected of resulting in chemical contamination of the island and surrounding waters. To help address this, the NOAA/ NOS National Centers for Coastal Ocean Science (NCCOS) collected sediment and fish samples for chemical contaminant analysis throughout Cocos Lagoon in May 2015, with local partners.

This document presents environmental data collected in August 2013 consisting of coral tissue (Pocillopora damicornis) contaminants and surface water nutrients offshore from Tinian in the Commonwealth of Northern Mariana Islands (CNMI). The study area is in and around the Tinian Marine Reserve on the southwest corner of the island. Despite being a marine protected area, there is very little information on pollution stressors to this protected ecosystem. These new data provide a survey of the system, including the magnitude and spatial extent of pollution in coral tissues. These data also provide an important starting point against which to measure future change.

NOAA Technical Memorandum NOS NCCOS ; 184

Primary sclerosing cholangitis (PSC) is a severe liver disease of unknown etiology leading to fibrotic destruction of the bile ducts and ultimately to the need for liver transplantation. We compared 3,789 PSC cases of European ancestry to 25,079 population controls across 130,422 SNPs genotyped using the Immunochip. We identified 12 genome-wide significant associations outside the human leukocyte antigen (HLA) complex, 9 of which were new, increasing the number of known PSC risk loci to 16. Despite comorbidity with inflammatory bowel disease (IBD) in 72% of the cases, 6 of the 12 loci showed significantly stronger association with PSC than with IBD, suggesting overlapping yet distinct genetic architectures for these two diseases. We incorporated association statistics from 7 diseases clinically occurring with PSC in the analysis and found suggestive evidence for 33 additional pleiotropic PSC risk loci. Together with network analyses, these findings add to the genetic risk map of PSC and expand on the relationship between PSC and other immune-mediated diseases.

A viral etiology of human breast cancer (HBC) has been postulated for decades since the identification of mouse mammary tumor virus (MMTV). The detection of MMTV env-like exogenous sequences (MMTVels) in 30% to 40% of invasive HBCs increased attention to this hypothesis. Looking for MMTVels during cancer progression may contribute to a better understanding of their role in HBC. Herein, we analyzed HBC preinvasive lesions for the presence of MMTVels. Samples were obtained by laser microdissection of FFPE tissues: 20 usual-type ductal hyperplasias, 22 atypical ductal hyperplasias (ADHs), 49 ductal carcinomas in situ (DCISs), 20 infiltrating ductal carcinomas (IDCs), and 26 normal epithelial cells collateral to a DCIS or an IDC. Controls included reductive mammoplastic tissue, thyroid and colon carcinoma, and blood samples from healthy donors. MMTVels were detected by fluorescence-nested PCR. DNA samples from the tissues of nine patients were analyzed by real-time quantitative PCR, revealing a different viral load correlated with stage of progression. Furthermore, as never previously described, the presence of MMTVels was investigated by chromogenic in situ hybridization. MMTVels were found in 19% of normal epithelial cells collateral to a DCIS or an IDC, 27% of ADHs, 82% of DCISs, and 35% of IDCs. No MMTVels were found in the control samples. Quantitative PCR and chromogenic in situ hybridization confirmed these results. These data could contribute to our understanding of the role of MMTVels in HBC.

This study examines whether there is differential productivity associated with teachers trained within Florida Agricultural & Mechanical University’s college of education relative to teachers trained in other colleges and schools affiliated with the same university. We also examined whether there is differential productivity associated with alternative majors within and between the college of education and other academic units. We measure the productivity of a teacher by the educational achievement of pupils assigned to that teacher during a given year. We find that among pupils taught by recent graduates of FAMU, there is greater academic achievement among elementary school pupils taught by a teacher with a college major in elementary education than among elementary school pupils taught by a teacher with a college major in either secondary education or a non-education subject area. However, relative to secondary education and non-education majors, elementary education majors provide less value-added in middle school and high school.

This study explores important statistical issues on the appropriate functional form and model specification of the value-added educational achievement equation. We also wish to estimate the causal effect of a teacher’s institution of academic preparation and pedagogical training. Standardized test scores, viz., the Florida Comprehensive Assessment Tests (FCAT), provide a measure of pupil academic achievement. Accordingly, this study uses a value-added regression model to establish whether there is a “college preparation effect” on the average pupil’s FCAT reading and mathematics scores. We find that value-added regression analysis fails to uncover robust and substantive college preparation effects. Regardless of race (African American, Hispanic, or white), male or female status, or FCAT mathematics versus FCAT reading, pupil academic achievement does not vary substantively according to a teacher’s college of preparation. Further, the statistical significance of teacher program effects also depends on the functional form and specification of the value-added model.

Some teacher preparation institutions may provide higher quality teachers than others. Pupil academic achievement is one measure of the quality of teaching. Standardized test scores, e.g., the Florida Comprehensive Assessment Tests (FCAT), provide a measure of pupil academic achievement. This study seeks to ascertain whether Florida Agricultural & Mechanical University (FAMU) has a “college preparation effect” on the average pupil’s FCAT reading and mathematics scores. We find that the quality of FAMU’s teachers is statistically indistinguishable from the quality of teachers prepared by all other public colleges and universities in the state of Florida. This appears to be a robust conclusion. Our results are roughly the same regardless of whether we confine the sample to pupils matched with traditionally trained teachers (college of education graduates), all teachers, all traditionally trained African American teachers, or all African American teachers.

Standard analysis of racial inequality incorporates racial classification as an exogenous binary variable. This approach obfuscates the importance of racial self-identity and clouds our ability to understand the relative importance of unobserved productivity-linked attributes versus market discrimination as determinants of racial inequality in labor market outcomes. Our examination of identity heterogeneity among African Americans suggests racial wage disparity is most consistent with weak colorism, while genotype disparity best describes racial employment differences. Further, among African Americans, the wage data are not consistent with the hypothesis that black-mixed race wage disparity can be explained by differences in unobserved productivity-linked productive attributes.

For 30 years, Africana Studies has developed as an interdisciplinary field. Although much attention has been paid within the field to the humanities and arts, much less has been paid to the social sciences, particularly economics. This analysis documents the presence of economists and economics course content among Africana Studies programs. The authors also discuss the presence of economists and economic content among leading general interest journals in Africana Studies and of economics content in several influential Africana Studies texts. Only 1.72% of the faculty members in leading Africana Studies departments are economists, and economics course content among Africana Studies programs is anemic. Also, there is little economics content in Africana journals, particularly peer-reviewed journals. Recommendations include incorporating accessible economics texts into course reading lists; encouraging African American students to take economics, calculus, and statistics; teaching statistics and economic theory in the context of course content; and adding economists to the editorial boards of Black Studies journals.

Biased policing against racial and ethnic minorities is an important public policy issue. Theoretical analysis and empirical results on this issue has been plagued by an assortment of problems which confront research on the nature and significance of police discrimination against social groups. This paper presents and applies a nonparametric test that is robust to a host of methodological difficulties. We theoretically and empirically contrast our non-parametric test with other tests that are prominent in the literature. Utilizing data provided by the Florida Highway Patrol, our empirical results strongly reject the null hypothesis that FHP troopers of different races do not engage in racially biased searches of stopped drivers. More particularly, there is evidence of police bias against African American male and Latino drivers by all officers and no evidence of police bias against white male drivers by any group of officers.

This article examines heterogeneity and income inequality among Hispanic Americans. Two processes that influence Hispanic heterogeneity include acculturation and labor market discrimination because of skin shade/phenotype. I focus on Hispanics because of their variation in phenotype, color, nativity, and language usage and also because of their recent large-scale integration into a society that historically has been characterized by bipolar racial categories that are putatively based on phenotype. This process provides a natural experiment for appraising the relative importance of acculturation, discrimination, and income inequality. I use data from two periods, 1979 and 1989, to determine the stability of identity formation among Mexican-Americans and other Hispanics. I find strong incentives favoring acculturation among Mexican- and Cuban-Americans. Americans of Mexican and Cuban descent but less so Puerto Ricans are able to increase annual income and hourly wages by acculturating into a non-Hispanic white racial identity. However, neither the abandonment of Spanish nor the abandonment of a specifically Hispanic racial self-identity is sufficient to overcome the penalties associated with having a dark complexion and non-European phenotype.

This paper provides an evaluation the intellectual contributions of Rhonda M. Williams. Specifically, we focus on Williams' theoretical and empirical contributions to the political economy of race.

There are 241,000 hectares of Scots pine forest in Great Britain or about 10 percent of the total forest area. Traditionally, a distinction has been drawn between a small area of native pinewoods with high conservation value in northern Scotland and the younger plantations of Scots pine to be found in many parts of Britain. The latter have been primarily managed for timber although they are now expected to meet multipurpose objectives including enhanced biodiversity. Silvicultural practices in the plantations are based upon a system of clear felling and artificial regeneration. However, older plantation stands can be colonised by rare species previously thought to be confined to the native pinewoods. The structure of Scots pine stands of different ages is examined using modern concepts of stand dynamics. The analysis highlights that the native pinewood stands have features characteristic of «old-growth» such as: a lower stocking density; more large trees; greater variation in diameter; a clumped distribution of stems; and appreciable quantities of standing deadwood. By contrast, most plantation stands have higher stocking densities, less variation in diameter, more uniform spacing and limited amounts of deadwood. By quantifying these structures it becomes possible to propose thinning regimes which can be introduced into plantations to accelerate the development of old-growth conditions without undue sacrifice of timber values. Natural disturbance histories in British pinewoods indicate a return period for stand replacing events (fire, windthrow) of once every 100 years which suggests that a maximum of 10 per cent of the pine resource should be managed as old growth stands. The age structure of some remnant pinewoods shows a lack of younger age classes and the desired old-growth habitat will diminish over time unless suitable plantation stands are managed as potential old-growth habitat. The maintenance of biodiversity in British pinewoods requires an integrated approach that applies to both the native pinewoods and the plantation stands. En Gran Bretaña existen 241.000 ha de Pino silvestre, lo que representa sobre el 10 % de la superficie forestal total. Tradicionalmente, se ha realizado una distinción entre una superficie pequeña de pinares nativos con un alto valor de conservación en el norte de Escocia y las plantaciones más jóvenes de Pino silvestre que se encuentran en muchas partes de Gran Bretaña. Las plantaciones se han gestionado principalmente para producción de madera aunque actualmente se espera que cumplan objetivos múltiples incluyendo el aumento de la biodiversidad. Las técnicas selvícolas de las plantaciones se basan en un sistema de cortas a hecho y regeneración artificial. Sin embargo, las plantaciones más adultas pueden colonizarse por especies raras previamente confinadas a los pinares nativos. Se examina la estructura de las masas de Pino silvestre de distintas edades utilizando conceptos modernos de la dinámica de las masas. El análisis resalta que los pinares nativos tienen rasgos característicos de «crecimiento viejo» como: menor densidad de existencias, mayor variación en diámetro, una distribución de pies en grupos, y apreciables cantidades de madera muerta en pie. En contraste, la mayoría de las plantaciones tienen mayor densidad de existencias, menor variación en diámetro, un espaciamiento más uniforme, y una limitada cantidad de madera muerta. Para cuantificar estas estructuras es posible proponer regímenes de claras que pueden introducirse en las plantaciones para acelerar el desarrollo de condiciones de crecimiento viejo sin un sacrificio excesivo de la producción de madera. La historia de las perturbaciones naturales de los pinares Británicos indican un período de retorno para los sucesos que reemplazan el rodal (fuego, apeo por viento) de una vez cada 100 años que sugiere que se puede gestionar como rodales de crecimiento viejo un máximo del 10 % de los recursos de los pinares. La estructura de edad de algunos pinares residuales muestra una falta de las clases de edad más jóvenes y el hábitat deseado de crecimiento viejo disminuirá con el tiempo a menos que las plantaciones adecuadas se gestionen como hábitats potenciales de crecimiento viejo. El mantenimiento de la biodiversidad en los pinares Británicos requiere una aproximación integrada que se aplica tanto a los pinares nativos como a las plantaciones.

This article examines the interrelationships among race, culture, skill, and the distribution of wages. I utilize a three-equation system to explore this process: skill is a multidimensional productive attribute measured by years of education and work effort; educational attainment is a function of class background and individual effort; and individual wage rates are a function of skill and class background. By further assuming that effort is differentially distributed across individuals and social groups, I am able to estimate reduced form equations for educational and earnings attainment, where both equations are functions of the class backgrounds and race of individuals. The collective results of this article challenge the conventional wisdom among economists that African American and Latino job skills are of a lower quality than white job skills. To the extent that effort is an important element of worker skill, our results suggest that neither African American nor Latino labor is of lower quality than white labor. The results regarding differences between African Americans and whites in educational attainment, i.e., African Americans are able to translate a given level of resources into higher levels of educational attainment, reaffirm previous findings in the literature. The results on Latino versus white educational attainment are novel. Additionally, unlike previous research, this article connects racial differences in the skill acquisition process to the economics of discrimination.

This paper utilizes the Box-Cox transformation of variables technique to empirically derive an industry wage equation. Section I presents the determinants of potential wage differentials between and within industries. Section II estimates a Box-Cox industry wage equation. Likelihood ratio tests on alternative specifications of this equation affirm that competitive structure is a significant determinant of the industry wage rate and that human capital specifications of the industry wage equation (for the manufacturing sector) are not statistically valid. Section III summarizes the results.

The paper theoretically examines the relationship between variable labor effort (also labeled efficiency wages), effective demand, and involuntary unemployment.

The gene for MRP7, a 40-kilodalton protein of the large subunit of the yeast mitochondrial ribosome, was identified in a lambda gt11 expression library by immunological screening with a monoclonal antibody to MRP7. An intact copy of MRP7 was then isolated from a yeast genomic library by colony hybridization. Gene disruption showed that MRP7 protein was essential for ribosomal function. Sequencing of MRP7 revealed a coding region for a basic (pI 10.6), 43.2-kilodalton protein containing 371 amino acid residues. Amino acid residues 28 to 112 of the deduced MRP7 sequence aligned with the 84 residues of the Escherichia coli ribosomal protein L27, but no significant similarity was detected between the carboxy-terminal 259 amino acids of MRP7 and other protein sequences in existing computer data bases. Within the aligned region, there was 49% amino acid identity between MRP7 and L27, compared with the 57% identity observed between L27 and its homolog in Bacillus stearothermophilus. The steady-state levels of the MRP7 protein and its mRNA were monitored in response to catabolite repression and to increased dosage of the MRP7 gene. The response to catabolite repression was characterized by a ninefold change in the level of the protein and little, if any, change in the level of the mRNA. In cells carrying the MRP7 gene on a high-copy-number plasmid, the mRNA was increased 20-fold, but there was no significant increase in MRP7 protein. Furthermore, MRP7 mRNA and protein accumulated at normal levels in [rho0] cells, which are devoid of 21S rRNA, indicating that the protein is relatively stable in the absence of ribosome assembly. Together, these results suggest that MRP7 is regulated posttranscriptionally, probably at the level of protein synthesis rather than protein turnover.

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