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Throughout the Phanerozoic, estimated CO2 levels from CO2 proxies generally correlate well with independent estimates of temperature. However, some proxy estimates of atmospheric CO2 during the Late Cretaceous and early Paleocene are low (<400 ppm), seemingly at odds with elevated sea surface temperature. Here we evaluate early Paleocene CO2 by applying a leaf gas‐exchange model to Platanites leaves of four early Paleocene localities from the San Juan Basin, New Mexico (65.66–64.59 Ma). We first calibrate the model on two modern Platanus species, Platanus occidentalis and P. × acerifolia, where we find the leaf gas‐exchange model accurately predicts present‐day CO2, with a mean error rate between 5% and 14%. Applying the model to the early Paleocene, we find CO2 varies between ∼660 and 1,140 ppm. These estimates are consistent with more recent CO2 estimates from boron, leaf gas‐exchange, liverwort, and paleosol proxies that all suggest moderate to elevated levels of CO2 during the Late Cretaceous and early Paleocene. These levels of atmospheric CO2 are more in keeping with the elevated temperature during this period. Plain Language Summary: Throughout Earth history, temperature and atmospheric CO2 usually track each other. During the Late Cretaceous to early Paleocene (∼70–60 Ma), global mean surface temperature was ∼8–12.5°C higher than today. However, CO2 estimates are variable, with some estimates equal to or less than present‐day CO2 (∼415 ppm) and at odds with the estimated global temperatures. Here we use a proxy based on leaf gas‐exchange principles (i.e., photosynthesis) to estimate early Paleocene CO2 from fossil Platanites leaves (family Platanaceae) of four early Paleocene localities from the San Juan Basin, New Mexico (65.66–64.59 Ma). We first test and calibrate the proxy on two modern Platanus species, Platanus occidentalis and P. × acerifolia. We find the leaf gas‐exchange model accurately predicts present‐day CO2. Applying the leaf gas‐exchange model to the early Paleocene, we find CO2 varies between ∼660 and 1,140 ppm. Our results are consistent with other proxies, such as boron, paleosol, leaf gas‐exchange, and liverwort proxies, that all suggest moderate to elevated levels of CO2 during the Late Cretaceous and early Paleocene. These levels of atmospheric CO2 are more in line with elevated temperature during this period, consistent with most observations of CO2 and temperature throughout the Phanerozoic. Key Points: Some CO2 proxy estimates from the Late Cretaceous‐early Paleocene are low (<400 ppm), seemingly at odds with elevated sea surface temperatureWe apply a leaf gas‐exchange model to Platanites leaves of four early Paleocene localities from the San Juan Basin, New MexicoOur CO2 estimates, between ∼660 and 1,140 ppm, are congruent with more recent estimates from several other proxy methods [ABSTRACT FROM AUTHOR]

Although rare, subclinical tuberculosis disease can be missed during evaluations for latent tuberculosis infection, and can manifest with symptoms during latent tuberculosis treatment. Among over 8000 patients treated for latent tuberculosis we found no evidence of acquired drug resistance, underscoring the safety of rifampin monotherapy for latent tuberculosis. [ABSTRACT FROM AUTHOR]

Abstract: Paleoecological studies document the net effects of atmospheric and climate change in a natural laboratory over timescales not accessible to laboratory or ecological studies. Insect feeding damage is visible on well‐preserved fossil leaves, and changes in leaf damage through time can be compared to environmental changes. We measured percent leaf area damaged on four fossil leaf assemblages from the Bighorn Basin, Wyoming, that range in age from 56.1 to 52.65 million years (Ma). We also include similar published data from three US sites 49.4 to ~45 Ma in our analyses. Regional climate was subtropical or warmer throughout this period, and the second oldest assemblage (56 Ma) was deposited during the Paleocene–Eocene Thermal Maximum (PETM), a geologically abrupt global warming event caused by massive release of carbon into the atmosphere. Total and leaf‐chewing damage are highest during the PETM, whether considering percent area damaged on the bulk flora, the average of individual host plants, or a single plant host that occurs at multiple sites. Another fossil assemblage in our study, the 52.65 Ma Fifteenmile Creek paleoflora, also lived during a period of globally high temperature and pCO2, but does not have elevated herbivory. Comparison of these two sites, as well as regression analyses conducted on the entire dataset, demonstrates that, over long timescales, temperature and pCO2 are uncorrelated with total insect consumption at the ecosystem level. Rather, the most important factor affecting herbivory is the relative abundance of plants with nitrogen‐fixing symbionts. Legumes dominate the PETM site; their prevalence would have decreased nitrogen limitation across the ecosystem, buffering generalist herbivore populations against decreased leaf nutritional quality that commonly occurs at high pCO2. We hypothesize that nitrogen concentration regulates the opposing effects of elevated temperature and CO2 on insect abundance and thereby total insect consumption, which has important implications for agricultural practices in today's world of steadily increasing pCO2. [ABSTRACT FROM AUTHOR]

Climate and environment strongly influence the size, shape, and toothiness (physiognomy) of plants' leaves. These relationships, particularly in woody non-monocotyledonous angiosperms, have been used to develop leaf-based proxies for paleoclimate and paleoecology that have been applied to reconstruct ancient terrestrial ecosystems for the last ~120 million years of Earth's history. Additionally, given that these relationships have been documented in living plants, they are important for understanding aspects of plant evolution and how plants respond to climatic and environmental changes. To conduct these types of analyses on modern and fossil plants, leaf physiognomy must be measured accurately using a reproducible methodology. This protocol describes a computer-based method for measuring and analyzing a variety of leaf physiognomic variables in modern and fossil leaves. This method allows for the measurement of leaf physiognomic traits, in particular variables related to leaf serrations, leaf area, leaf dissection, and linearity that are used in the digital leaf physiognomy proxy for reconstructing paleoclimate, as well as petiole width and leaf area, which are used for reconstructing leaf mass per area, a paleoecological proxy. Because this digital leaf trait measurement method can be applied to fossil and living plants, it is not limited to applications related to reconstructing paleoclimate and paleoecology. It can also be used to explore leaf traits that may be informative for understanding the function of leaf morphology, leaf development, phylogenetic relationships of leaf traits, and plant evolution.

Paleoecological studies document the net effects of atmospheric and climate change in a natural laboratory over timescales not accessible to laboratory or ecological studies. Insect feeding damage is visible on well-preserved fossil leaves, and changes in leaf damage through time can be compared to environmental changes. We measured percent leaf area damaged on four fossil leaf assemblages from the Bighorn Basin, Wyoming, that range in age from 56.1 to 52.65 million years (Ma). We also include similar published data from three US sites 49.4 to ~45 Ma in our analyses. Regional climate was subtropical or warmer throughout this period, and the second oldest assemblage (56 Ma) was deposited during the Paleocene-Eocene Thermal Maximum (PETM), a geologically abrupt global warming event caused by massive release of carbon into the atmosphere. Total and leaf-chewing damage are highest during the PETM, whether considering percent area damaged on the bulk flora, the average of individual host plants, or a single plant host that occurs at multiple sites. Another fossil assemblage in our study, the 52.65 Ma Fifteenmile Creek paleoflora, also lived during a period of globally high temperature and pCO 2, but does not have elevated herbivory. Comparison of these two sites, as well as regression analyses conducted on the entire dataset, demonstrates that, over long timescales, temperature and pCO 2 are uncorrelated with total insect consumption at the ecosystem level. Rather, the most important factor affecting herbivory is the relative abundance of plants with nitrogen-fixing symbionts. Legumes dominate the PETM site; their prevalence would have decreased nitrogen limitation across the ecosystem, buffering generalist herbivore populations against decreased leaf nutritional quality that commonly occurs at high pCO 2. We hypothesize that nitrogen concentration regulates the opposing effects of elevated temperature and CO 2 on insect abundance and thereby total insect consumption, which has important implications for agricultural practices in today's world of steadily increasing pCO 2.

Purpose of Review: This article summarizes research and commentaries on psychotherapy for adults with intellectual disabilities published since 2008., Recent Findings: There have been very few empirical studies of the effectiveness of psychotherapy in this context over recent years despite a strong perception that such approaches are not only necessary but also of great value. There have been some interesting, though so far only suggestive, findings concerning the relationship between intellectual level and suitability for treatment, primarily with cognitive behavioural therapy. Therapies based on mindfulness are emerging as important new developments. Despite their heritage, psychodynamic approaches continue to rely on opinion over evidence to support their use., Summary: Research on both processes in therapy and its outcomes needs to be undertaken with renewed vigour if specialist psychotherapy for people with intellectual disability is to flourish, or indeed survive, in the public healthcare system. However, it may have much a broader value for people with intellectual disability, especially those in residential services, than can be easily quantified.