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Background: African-Americans rank last among all racial groups for age-adjusted colorectal cancer mortality, 5-year survival rates, and rates of screening. Access to care does not fully explain racial disparities in rates of CRC and mortality. Sociocultural attitudes can predict probabilities of CRC screening. Aims: The objective of this study is to identify factors that influence colorectal cancer screening behavior in African-American men. Methods: Semi-structured interviews were conducted among 32 African-American men. Transcripts were analyzed using MAXQDA software. We then conducted a cross-sectional survey of 103 African-American men, using previously validated scales related to colorectal cancer screening and determinants. Data were analyzed with SPSS. Results: In the interview phase, beliefs relating to masculinity emerged as factors that hindered participation in screening. Overwhelmingly, participants felt that having an in-depth discussion about colorectal cancer with their provider was critical to enabling them to get screened. The survey phase demonstrated that most participants had poor colorectal cancer knowledge, as only 16% passed the knowledge test. Forty-eight percentage agreed that their provider did not recommend getting screened. Those who had been previously screened for colorectal cancer scored higher in total and on all subsets of the masculinity index than those who had not (p <.01). The most persuasive messages were those related to themes of masculinity. Conclusion: This study provides a novel sociocultural perspective about colorectal cancer screening in African-American men. Our findings highlight the importance of family, masculinity, and community when promoting colorectal cancer screening to this population. [ABSTRACT FROM AUTHOR]

The Oligocene-Miocene boundary Asian climatic reorganization linked to the northward migration of the East Asian monsoon into subtropical China is a potentially important but poorly constrained atmospheric CO2 consumption process. Here, we performed a first-order estimate of the CO2 consumption induced by silicate chemical weathering and organic carbon burial in subtropical China related to this climatic reorganization. Our results show that an increase in long-term CO2 consumption by silicate weathering varies from 0.06×1012 to 0.87×1012 mol yr−1 depending on erosion flux reconstructions, with an ~50% contribution of Mg-silicate weathering since the late Oligocene. The organic carbon burial flux is approximately 25% of the contemporary CO2 consumption by silicate weathering. The results highlight the significant role of weathering of the Mg-rich upper continental crust in East China, which would contribute to the rapid decline in atmospheric CO2 during the late Oligocene and the Neogene rise in the seawater Mg content. If this climatic reorganization was mainly induced by the Tibetan Plateau uplift, our study suggests that the growth of the Himalayan-Tibetan Plateau can lead to indirect modification of the global carbon and magnesium cycles by changing the regional hydrological cycle in areas of East Asia that are tectonically less active. [ABSTRACT FROM AUTHOR]

Exceedingly strong aeolian dust activity has occurred in inland Asia. Comparisons of the late Cenozoic sedimentation rates between aeolian and fluvial‐lacustrine sequences around the northern Tibetan Plateau suggest that aeolian process has played an important role in the erosion, weathering and deposition of sediment. However, recognizing dust as an important source in fluvial‐lacustrine sequences is a vital but difficult task. Here, clay‐sized mineral and elemental records of regional silicate weathering histories are revisited during the period of Asian dust expansion at ~9–8 Ma. The aeolian dust input from the Tianshan‐Altay Orogens into the Jiuquan Basin is identified using the Th/Sc ratio while that from the Qilian Shan into the Xining Basin is identified based on inconsistent fine‐grained silicate weathering proxies. Our study suggests that the use of appropriate dust provenance tracers and recognition of wind transport‐induced changes in dust grain size and chemistry can provide useful aeolian dust discrimination approaches. [ABSTRACT FROM AUTHOR]

Fast late Miocene global cooling since ∼7 Ma accompanied by less changeable atmospheric CO2 levels revealed by existing proxy reconstructions has suggested an intriguing tectonic‐climate link that remains controversial. Here, we present late Cenozoic clay mineral records of the silicate weathering intensity from the Chinese Loess Plateau and northeastern Tibetan Plateau to demonstrate a remarkable increase in silicate weathering intensity at ∼9–7 Ma induced by enhanced monsoon. This change caused CO2 consumption ranging from 0.18 to 1.8 × 1011 mol C yr−1 over the East Asian monsoon region, accounting for 0.2%–2% of the modern continental silicate weathering flux, thus providing an additional atmospheric CO2 sink. Moreover, we propose that this additional sink may have contributed to the large atmospheric CO2 consumption and fast global cooling in the late Miocene, which ultimately caused the onset of the Northern Hemisphere glaciation at ∼7 Ma. Key Points: Late Cenozoic clay mineral records of silicate weathering intensity in the northeastern Tibetan Plateau and Chinese Loess PlateauSilicate weathering intensity has been greatly enhanced over the East Asian monsoon region at ∼9–7 MaMonsoon‐forced silicate weathering acting as an emerging CO2 sink may regulate fast global cooling since ∼7 Ma [ABSTRACT FROM AUTHOR]

Understanding the effects of arbuscular mycorrhizal fungi (AMF) under different environmental contexts on overyielding in intercropping systems can be instructive in optimizing productivity and ecosystem services. A greenhouse study was conducted with maize and faba bean monocultures or intercropping at low phosphorus (P) and high P levels with three different water availabilities, and inoculated with or without AMF species Funneliformis mosseae. At low P level, overyielding was mainly due to the increase of maize biomass promoted by AMF relative to faba bean. Whereas in high P soils, overyielding was observed at all treatments, regardless of AMF. Inoculation of AMF significantly improved maize rather than faba bean P uptake, water use efficiency and photosynthesis rate, in particular at the low P level. This study identified the context dependence of AMF in influencing overyielding in maize/faba bean intercropping and demonstrates the importance of AMF in sustainable agricultural production. [ABSTRACT FROM AUTHOR]

The uplift of the Tibetan Plateau (TP) during the late Cenozoic is thought to be one of crucial factors controlling Asian climate. However, the complex interaction between tectonics and climate change is still unclear. Here we present the first record of clay mineralogy and elemental geochemistry covering ~12.7–4.8 Ma in a fluvial‐lacustrine sequence in the Xining Basin. Geochemical provenance proxies (Th/Sc, Zr/Sc, and Cr/Zr) in the <2‐μm fraction show a significant provenance change at ~8.8 Ma. Silicate‐based weathering indexes (CIA, CIW, and PIA) displayed coeval changes with provenance but discrepant changes with regional climate. Since the clay mineralogy exhibits significant change at ~7.8 Ma uncorrelated with modifications in provenance, it can be employed to reveal regional climate change. The rise in illite and associated decrease in the sum of smectite and illite/smectite mixed layers reflect gradual and slow aridification since ~12.7 Ma with intensified drying since ~7.8 Ma until approaching the modern climate status. Our results, together with other regional climatic and tectonic records, clearly illustrate that accelerated uplift of the northeastern TP since ~8–9 Ma has mainly modulated the regional erosion, weathering, transportation, and sedimentation and amplified the global cooling and drying trend toward the regional climate of modern conditions. Our study suggests that in the tectonically active northeastern TP, a comprehensive mineralogical and geochemical investigation of the fine‐grained fraction of the basin sediments could retrieve the interactions between tectonics and climate behind the complex change in exhumed lithology and sedimentary routing systems. Key Points: A long‐term gradual aridification since 12.7 Ma and an enhanced drying event since ~7.8 Ma occurred in the Xining BasinUplift of the northeastern Tibetan Plateau was the major driver of the evolution of regional climate and landscape since the late MioceneClay minerals are well‐used potential proxies for paleoclimatic reconstructions in complex sedimentary routing systems [ABSTRACT FROM AUTHOR]

Abstract: Palygorskite is a widely used indicator of semiarid to arid environments in paleoclimate studies. In this study, we present detailed mineralogical and geochemical investigations exploring the genesis of palygorskite found in Eocene fluvial sediment in the northern Qaidam Basin on the northeastern Tibetan Plateau. The presence of two types of palygorskite is revealed, based on their crystallinity characteristics and distinctive rare earth element (REE) patterns in the coexisting clay fraction. Well‐crystallized palygorskite samples are characterized by remarkably negative Ce anomalies and obvious middle rare earth element enrichment. Poorly crystallized palygorskite samples generally exhibit positive Ce anomalies and less pronounced middle rare earth element enrichment, which resemble those of nonpalygorskite‐bearing clay samples. Given the presence of an overall oxidized fluvial sedimentary environment, we attribute the well‐crystallized palygorskite (which has textures comprising long, interwoven fibers) to direct precipitation (i.e., neoformation) occurring within a reducing environment during early/postdepositional processes while the poorly crystallized palygorskite (which is characterized by short, club‐shaped single crystals) originates as catchment‐delivered detritus. These poorly crystallized palygorskites occur mostly in 49.5–47.0 Ma and are accompanied by decreasing kaolinite content, increasing chlorite content, and abundant xerophytic spore‐pollen from the Qaidam Basin, and its neighboring Xining Basin. Collectively, these evidences suggest that a less humid climate followed after the Early Eocene Climate Optimum. [ABSTRACT FROM AUTHOR]

Two chiral carboxylic acid functionalized micro- and mesoporous metal-organic frameworks (MOFs) are constructed by the stepwise assembly of triple-stranded heptametallic helicates with six carboxylic acid groups. The mesoporous MOF with permanent porosity functions as a host for encapsulation of an enantiopure organic amine catalyst by combining carboxylic acids and chiral amines in situ through acid-base interactions. The organocatalyst-loaded framework is shown to be an efficient and recyclable heterogeneous catalyst for the asymmetric direct aldol reactions with significantly enhanced stereoselectivity in relative to the homogeneous organocatalyst. [ABSTRACT FROM AUTHOR]

Two chiral carboxylic acid functionalized micro- and mesoporous metal-organic frameworks (MOFs) are constructed by the stepwise assembly of triple-stranded heptametallic helicates with six carboxylic acid groups. The mesoporous MOF with permanent porosity functions as a host for encapsulation of an enantiopure organic amine catalyst by combining carboxylic acids and chiral amines in situ through acid-base interactions. The organocatalyst-loaded framework is shown to be an efficient and recyclable heterogeneous catalyst for the asymmetric direct aldol reactions with significantly enhanced stereoselectivity in relative to the homogeneous organocatalyst. [ABSTRACT FROM AUTHOR]