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Scores on five differently speeded parts of a nonverbal reasoning test were analyzed to determine the relationship between the abilities measured by the speeded and the unspeeded parts. Two orthogonal factors were found: One is described as the ability to answer the problems correctly; the other is described as the tendency to answer the problems quickly. The first factor was found to be somewhat more valid than the second for predicting grades at the U. S. Naval Academy. The suggestion is made that descriptions of tests are incomplete unless they include some specification describing the speededness of the test.
This paper describes a relationship between the variance-covariance matrix of test items and Woodbury's concept of the standard length of a test. An index of item-test relationship is described in standard length terms. The sum of these indices for the items in a test is equal to the square of Jackson's coefficient of sensitivity.
Coastal wetlands are hotspots of carbon sequestration, and their conservation and restoration can help to mitigate climate change. However, there remains uncertainty on when and where coastal wetland restoration can most effectively act as natural climate solutions (NCS). Here, we synthesize current understanding to illustrate the requirements for coastal wetland restoration to benefit climate, and discuss potential paths forward that address key uncertainties impeding implementation. To be effective as NCS, coastal wetland restoration projects will accrue climate cooling benefits that would not occur without management action (additionality), will be implementable (feasibility) and will persist over management-relevant timeframes (permanence). Several issues add uncertainty to understanding if these minimum requirements are met. First, coastal wetlands serve as both a landscape source and sink of carbon for other habitats, increasing uncertainty in additionality. Second, coastal wetlands can potentially migrate outside of project footprints as they respond to sea-level rise, increasing uncertainty in permanence. To address these first two issues, a system-wide approach may be necessary, rather than basing cooling benefits only on changes that occur within project boundaries. Third, the need for NCS to function over management-relevant decadal timescales means methane responses may be necessary to include in coastal wetland restoration planning and monitoring. Finally, there is uncertainty on how much data are required to justify restoration action. We summarize the minimum data required to make a binary decision on whether there is a net cooling benefit from a management action, noting that these data are more readily available than the data required to quantify the magnitude of cooling benefits for carbon crediting purposes. By reducing uncertainty, coastal wetland restoration can be implemented at the scale required to significantly contribute to addressing the current climate crisis.
Background: Extrapulmonary nontuberculous mycobacteria (ENTM) infections are difficult to treat and often require prolonged therapy or surgery. Few population-based studies describe ENTM epidemiology, though well-known healthcare-associated outbreaks have occurred. Using the first year of multi-site ENTM surveillance, we characterized rates and how frequently ENTM infections may be related to healthcare. Methods: CDC’s Emerging Infections Program conducted active, laboratory- and population-based surveillance for ENTM cases in 4 sites (Colorado [5 counties], Minnesota [statewide], New York [1 county], and Oregon [statewide]) in 2021. An incident ENTM case was NTM isolation from a non-pulmonary specimen, excluding stool or rectal swabs, in a resident of the surveillance area without either medical record documentation of prior ENTM infection or isolation of ENTM in the prior 12 months. Demographic, clinical, information on selected healthcare and community exposures, and laboratory data were collected via medical record review. We calculated incidence per 100,000 population using U.S. Census population estimates and performed descriptive analyses. Results: A total of 180 incident ENTM cases were reported in 2021. The crude annual incidence rate was 1.3 per 100,000 persons. Incidence increased with age (from 0.95 per 100,000 among 0–17 year-olds to 2.65 per 100,000 among persons ≥65), ranged from 0.8 among non-Hispanic Asian persons to 1.6 per 100,000 in non-Hispanic Black persons, and was similar among males (1.3 per 100,000) and females (1.4 per 100,000; Figure 1). Mycobacterium avium complex (64 [35.6%]) was the most frequently isolated species group, followed by Mycobacterium chelonae complex (31 [17.2%]). Skin and soft tissue infections were the most frequent infection type (37 [20.6%]); 27 cases (15.0%) were associated with disseminated and/or only bloodstream infection, and 56 cases (31.1%) had no infection type documented. Among 93 cases with localized ENTM infections (i.e., infections that were not disseminated and/or only bloodstream infections), 38.7% had only healthcare-related exposures, 14% had only community-related exposures and 6.5% had both exposure types at the site of infection (Figure 2). Healthcare-related exposures at the infection site included surgery (23.7%), injection/infusion (21.5%), and medical devices (18.3%). The most frequent community-related exposure at the infection site was trauma (17.2%). Only one case was part of a known outbreak, which was healthcare-associated. Conclusions: ENTM infections are relatively rare, but nearly half of patients with localized ENTM infections had prior healthcare-related exposures. This indicates that the burden of ENTM infections related to healthcare may be much larger than what has been suggested from reported outbreaks.
A principal mode of corrosion in combustion or fuel cell environments is the formation of volatile hydroxides and oxyhydroxides from metal or oxide surfaces at high temperatures. It is important to determine the degree of volatility and accurate thermodynamic properties for these hydroxides. Significant gaseous metal hydroxides/oxyhydroxides are discussed, along with available experimental and theoretical methods of characterizing species and determining their thermodynamic properties.
The use of monthly intranasal mupirocin was associated with a significant reduction in the rate of methicillin-resistant Staphylococcus aureus transmission and Staphylococcus aureus invasive infection in a large neonatal intensive care unit. Resistance to mupirocin emerged over time, but it was rare and was not associated with adverse clinical outcomes.
The direct sale of emission allowances by auction is an emerging characteristic of cap-and-trade programs. This study is motivated by the observation that all of the major implementations of cap-and-trade regulations for the control of air pollution have started with a generous allocation of allowances relative to recent emissions history, a situation we refer to as a “loose cap.” Typically more stringent reductions are achieved in subsequent years of a program. We use an experimental setting to investigate the effects of a loose cap environment on a variety of auction types. We find that all auction formats studied are efficient in allocating emission allowances, but auction revenues tend to be lower relative to competitive benchmarks when the cap is loose. Regardless of whether the cap is tight or loose, the different auction formats tend to yield comparable revenues toward the end of a series of auctions. However, aggressive bidding behavior in initial discriminatory auctions yields higher revenues than in the other auction formats, a difference that disappears as bidders learn to adjust their bids closer to the cut-off that separates winning and losing bids.
The advent of sequencing technologies has revolutionized our understanding and approach to studying biological systems. Indeed, whole-genome sequencing projects have already targeted many different species, enabling the identification of most genes in those organisms. However, observed phenotypes cannot be explained by genes alone, but rather by the interactions that their products establish under some environmental conditions (Waddington 1957). Thus, it is through the analysis of these interaction net-works (e.g. regulatory, metabolic, molecular, or genetic) that we can better understand the genotype-to-phenotype relationship, the complexity and evolution of organisms, or the differences among individuals of the same species. The topology and dynamics of these biological networks can be unveiled by systematic perturbation of their nodes (i.e. genes). For instance, upon single-gene deletions in Saccharomyces cerevisiae under standard laboratory conditions, most genes (∼80%) were not found to be essential for cell viability (Giaever et al. 2002). Though many of these genes may be required for growth in other environments (Hillenmeyer et al. 2008), this result suggests extensive functional redundancy among genes. Such functional buffering confers robustness to biological networks and shields the cellular machinery from genetic perturbations (Hartman et al. 2001). Additionally, the small effect on phenotype that many gene deletions exhibit (see Figure 2.1) evidences that single perturbations alone cannot capture the complexity of the genotype-to-phenotype relationship. Therefore, a combinatorial approach to gene perturbations is best suited to elucidate biological systems and can enable a better characterization of genes and cellular functioning.
Definition of genetic interaction
Genetic interactions reveal functional relations between genes that contribute to a pheno-typic trait. William Bateson first introduced the term, formerly known as epistasis (see Phillips [1998] for a description on the origin and evolution of the definition), to refer to an allele at one locus preventing a variant at another from manifesting its effect (Bateson 1909).
A key and measurements are presented for the eggs of 23 species of Aedes. Twenty species from California and Nevada are illustrated, and eleven previously undescribed eggs are described.
Epitaxial graphene (EG) grown on the carbon-face of SiC has been shown to exhibit higher carrier mobilities in comparison to other growth techniques amenable to wafer-scale graphene fabrication. The transfer of large area (>mm2) graphene films to substrates amenable for specific applications is desirable. We demonstrate the dry transfer of EG from the C-face of 4H-SiC onto SiO2, GaN and Al2O3 substrates via two approaches using either 1) thermal release tape or 2) a spin-on, chemically-etchable dielectric. Van der Pauw devices fabricated from C-face EG transferred to SiO2 gave similar mobility values and up to three fold reductions in carrier density in comparison to devices fabricated on as-grown material.
Infants' sensitivity to word units in fluent speech was examined by inserting 1 sec pauses either at boundaries between successive words (Coincident versions) or between syllables within words (Noncoincident versions). In Experiment 1, 24 11-month-olds listened significantly longer to the Coincident versions. In Experiment 2, 24 four-and-a-half-and 24 nine-month-olds did not exhibit the preference for the Coincident versions that the 11-month-olds showed. When the stimuli were low-pass filtered in Experiment 3, 24 11-month-olds showed no preference for the Coincident versions, suggesting they rely on more than prosodic cues. New stimulus materials in Experiment 4 indicated that responses by 24 11-month-olds to the Coincident and Noncoindent versions did not depend solely on prior familiarity with the targets. Two groups of 30 11-month-olds tested in Experiment 5 were as sensitive to boundaries for Strong/Weak words as for Weak/Strong words. Taken together, the results suggest that, by 11 months, infants are sensitive to word boundaries in fluent speech, and that this sensitivity depends on more than just prosodic information or prior knowledge of the words.
Background. Although caffeine is the most commonly used psychoactive substance and often produces symptoms of toxicity and dependence, little is known, especially in community samples, about the association between caffeine use, toxicity and dependence and risk for common psychiatric and substance use disorders.
Method. Assessments of lifetime maximal caffeine use and symptoms of caffeine toxicity and dependence were available on over 3600 adult twins ascertained from the population-based Virginia Twin Registry. Lifetime histories of major depression (MD), generalized anxiety disorder (GAD) and panic disorder, alcohol dependence, adult antisocial behavior and cannabis and cocaine abuse/dependence were obtained at personal interview. Logistic regression analyses in the entire sample and within monozygotic (MZ) twin pairs were conducted in SAS.
Results. In the entire sample, measures of maximal caffeine use, heavy caffeine use, and caffeine-related toxicity and dependence were significantly and positively associated with all seven psychiatric and substance use disorders. However, within MZ twin pairs, controlling for genetic and family environmental factors, these associations, while positive, were all non-significant. These results were similar when excluding twins who denied regular caffeine use.
Conclusions. Maximal lifetime caffeine intake and caffeine-associated toxicity and dependence are moderately associated with risk for a wide range of psychiatric and substance use disorders. Analyses of these relationships within MZ twin pairs suggest that most of the observed associations are not causal. Rather, familial factors, which are probably in part genetic, predispose to both caffeine intake, toxicity and dependence and the risk for a broad array of internalizing and externalizing disorders.
Anew assistant professor of political science, who we shall call “Dr.Politics,” stands at the door of the exhibit hall at the AnnualMeeting of the American Political Science Association gazing at thecrowds gathering at the booths of the leading publishers ofscholarly work in political science. Dr. Politics' dissertation hasbeen finished, defended, and filed with the graduate school. Thedissertation committee members have told Dr. Politics that thedissertation is but one revision away from being a completed bookmanuscript that will be attractive to many academic presses. Dr.Politics' prestigious department requires at least one publishedbook and one on the way for tenure. The chair expects the first bookto be a revised version of the dissertation. How does Dr. Politicsnavigate the new world of publishing?
The findings reported in the Letter to the Editor authored by Bungener and Jouvent are consistent with results we have presented here (Castellon et al., 2000) and again underscore the importance of considering the potentially multifactorial nature of depression in many neurologic diseases/disorders. We have suggested, although the idea is hardly a new one, that depression in HIV/AIDS can be secondary to any of multiple potential etiologies. For example, it may be a direct central nervous system (CNS) consequence of infection (i.e., neurochemical and/or neuropathological changes), a result of increased exposure to social, medical, and financial stressors secondary to living with HIV, a reaction to multiple losses (e.g., bereavement, loss of instrumental capacity), or be an admixture of multiple etiological factors. The phenomenology of this disruption of mood, motivation, and affect may differ as a function of etiology/pathophysiology. We believe that a prominent amotivation/apathy syndrome may be a more pure manifestation of the CNS effects of HIV-1 infection than is the more heterogeneous construct of depression and therefore more closely associated with other putative measures of CNS integrity (e.g., neurocognitive performance).
Prominent apathy and/or irritability are frequently observed among individuals infected with the human immunodeficiency virus (HIV). Although these symptoms often occur as part of a mood disorder, compelling evidence suggests that they may occur independently of depression in neurologic disease/disorder. The current study examined the prevalence of both apathy and irritability among a sample of HIV-infected individuals and explored the degree to which these neuropsychiatric (NP) phenomena were associated with performance on neurocognitive measures thought to be sensitive to the potential CNS effects of HIV-1. Clinician-administered rating scales assessing apathy and irritability were administered to 65 HIV-seropositive (HIV+) and 21 HIV-seronegative (HIV−) participants who also completed a dual-task reaction time paradigm and the Stroop task. NP disturbance was significantly more prevalent among HIV+ participants compared with HIV− controls and was associated with specific neurocognitive deficits suggestive of executive dysfunction. Relative to both HIV− controls and to neuropsychiatrically intact HIV+ participants, those HIV+ individuals with evidence of prominent apathy and/or irritability showed deficits in dual-task, but not single-task, performance and on the interference condition of the Stroop. Unexpectedly, NP disturbance did not show a robust relationship with HIV disease stage. These results suggest that the presence of prominent apathy and/or irritability among HIV+ individuals may signify greater HIV-associated CNS involvement. In HIV/AIDS, the disruption of frontal–subcortical circuits may be a common mechanism causing both executive dysfunction and NP disturbance. (JINS, 2000, 6, 336–347.)
The Early Iron Age enclosures and associated sites on Sutton Common on the western edge of the Humberhead Levels contain an exceptional variety of archaeological data of importance not only to the region but for the study of later prehistory in the British Isles. Few other later prehistoric British sites outside the East Anglian fens and the Somerset Levels have thus far produced the quantity and quality of organically preserved archaeological materials that have been found, despite the small scale of the investigations to date. The excavations have provided an opportunity to integrate a variety of environmental analyses, of wood, pollen, beetles, waterlogged and carbonised plant remains, and of soil micromorphology, to address archaeological questions about the character, use, and environment of this Early Iron Age marsh fort. The site is comprised of a timber palisaded enclosure and a succeeding multivallate enclosure linked to a smaller enclosure by a timber alignment across a palaeochannel, with associated finds ranging in date from the Middle Bronze Age to the Roman and medieval periods. Among the four adjacent archaeological sites is an Early Mesolithic occupation site, also with organic preservation, and there is a Late Neolithic site beneath the large enclosure. Desiccation throughout the common is leading to the damage and loss of wooden and organic remains. It is hoped that the publication of these results, of investigations between 1987 and 1993, will lead to a fuller investigation taking place.
All horizontal underground structures were roots and not rhizomes. The small, light-colored feeder roots are short-lived and consist mainly of primary tissue. Only one transition zone per clone was found. This was found in the collet (lower hypocotylary swelling). The transition from exarch, radial stele of the root, to endarch, collateral stele of the upper collet, was complete in approximately 2500 microns. All root primordia examined had endogenous origin from pericycle and pericyclic tissues. Buds arose endogenously in roots but exogenously in the region of the hypocotyl with endarch protoxylem. Primordia were often identified as roots or shoots prior to their emergence from the main axis.
The notion that there is a category mistake or some other conceptual confusion in regarding seeing, hearing, and other forms of perception as events, states, or processes is incorrect. Ryle's analysis of “seeing” as an achievement word does not rule out our regarding seeing as an event, but in fact suggests that we do so when we carry the analysis beyond the point where Ryle leaves it. Furthermore there are uses of “see” not noticed by Ryle which justify our saying that within certain contexts seeing is a state and within other contexts a process. The question of what these events, states, and processes are cannot be met without recognizing a fundamental duality of aspect that characterizes perception. This duality can be formulated in terms of the way perception is known. One who observes a perceiver knows the perceiver's perception in a categorically different way than the perceiver knows it. From this it can be seen that perceptual events, states, and processes have both a physical aspect and an epistemological aspect. Any attempt to reduce one of these aspects to the other would involve a category mistake.