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121.
Tibet’s ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to ∼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This “Shangri-La”–like ecosystem experienced monsoon seasonality with a mean annual temperature of ∼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.

The Tibetan Plateau, once thought of as entirely the product of the India–Eurasia collision, is known to have had significant complex relief before the arrival of India early in the Paleogene (13). This large region, spanning ∼2.5 million km2, is an amalgam of tectonic terranes that impacted Asia long before India’s arrival (4, 5), with each accretion contributing orographic heterogeneity that likely impacted climate in complex ways. During the Paleogene, the Tibetan landscape comprised a high (>4 km) Gangdese mountain range along the southern margin of the Lhasa terrane (2), against which the Himalaya would later rise (6), and a Tanghula upland on the more northerly Qiangtang terrane (7). Separating the Lhasa and Qiangtang blocks is the east–west trending Banggong-Nujiang Suture (BNS), which today hosts several sedimentary basins (e.g., Bangor, Nyima, and Lunpola) where >4 km of Cenozoic sediments have accumulated (8). Although these sediments record the climatic and biotic evolution of central Tibet, their remoteness means fossil collections have been hitherto limited. Recently, we discovered a highly diverse fossil assemblage in the Bangor Basin. These fossils characterize a luxuriant seasonally wet and warm Shangri-La forest that once occupied a deep central Tibetan valley along the BNS, and provide a unique opportunity for understanding the evolutionary history of Asian biodiversity, as well as for quantifying the paleoenvironment of central Tibet.*Details of the topographic evolution of Tibet are still unclear despite decades of investigation (4, 5). Isotopic compositions of carbonates recovered from sediments in some parts of central Tibet have been interpreted in terms of high (>4 km) Paleogene elevations and aridity (9, 10), but those same successions have yielded isolated mammal (11), fish (12), plant (1318), and biomarker remains (19) more indicative of a low (≤3-km) humid environment, but how low is poorly quantified. Given the complex assembly of Tibet, it is difficult to explain how a plateau might have formed so early and then remained as a surface of low relief during subsequent compression from India (20). Recent evidence from a climate model-mediated interpretation of palm fossils constrains the BNS elevation to below 2.3 km in the Late Paleogene (16), but more precise paleoelevation estimates are required. Further fossil discoveries, especially from earlier in the BNS sedimentary records, would document better the evolution of the Tibetan biota, as well as informing our understanding of the elevation and climate in an area that now occupies the center of the Tibetan Plateau.Our work shows that the BNS hosted a diverse subtropical ecosystem at ∼47 Ma, and this means the area must have been both low and humid. The diversity of the fossil flora allows us to 1) document floristic links to other parts of the Northern Hemisphere, 2) characterize the prevailing paleoclimate, and 3) quantify the elevation at which the vegetation grew. We propose that the “high and dry” central Tibet inferred from some isotope paleoaltimetry (9, 10) reflects a “phantom” elevated paleosurface (20) because fractionation over the bounding mountains allowed only isotopically light moist air to enter the valley, giving a false indication of a high elevation (21).  相似文献   
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We report the first pharmacokinetic and clinical response data from a patient with unresectable hepatocellular cancer treated with a new drug, ADI PEG20,000 mw (arginine deiminase-polyethylene glycol 20,000 molecular weight). A single patient with idiopathic cirrhosis and unresectable hepatocellular cancer was treated with escalating dosages of ADI-PEG20,000 mw. Human hepatocellular cancer has been found to be arginine-dependent for growth because of loss of expression or arginosuccinate synthetase, the rate-limiting enzyme in the conversion of citrulline to arginine. Thus, an arginine-degrading enzyme like ADI-PEG20,000 mw should produce cell death in hepatocellular cancer cells without significantly affecting normal cells. There was a dose-dependent reduction of plasma arginine levels after weekly intramuscular administration of ADI-PEG20,000 mw. Successive treatment cycles at the optimal biologic dose of 160 IU/m2 led to reduction in tumor size and serum alpha-fetoprotein levels. Sufficient tumor cytoreduction was achieved with ADI-PEG20,000 mw treatment to permit surgical treatment. The patient developed no toxicities or side effects related to ADI-PEG20,000 mw treatment. The results in a single patient with unresectable hepatocellular cancer treated with ADI-PEG20,000 mw suggests this may be a promising, low-toxicity treatment. Full-scale clinical trials have been initiated.  相似文献   
124.

Purpose

To image multidimensional flow in fetuses using golden-angle radial phase contrast cardiovascular magnetic resonance (PC-CMR) with motion correction and retrospective gating.

Methods

A novel PC-CMR method was developed using an ungated golden-angle radial acquisition with continuously incremented velocity encoding. Healthy subjects (n?=?5, 27?±?3 years, males) and pregnant females (n?=?5, 34?±?2 weeks gestation) were imaged at 3 T using the proposed sequence. Real-time reconstructions were first performed for retrospective motion correction and cardiac gating (using metric optimized gating, MOG). CINE reconstructions of multidimensional flow were then performed using the corrected and gated data.

Results

In adults, flows obtained using the proposed method agreed strongly with those obtained using a conventionally gated Cartesian acquisition. Across the five adults, bias and limits of agreement were ??1.0 cm/s and [??5.1, 3.2] cm/s for mean velocities and???1.1 cm/s and [??6.5, 4.3] cm/s for peak velocities. Temporal correlation between corresponding waveforms was also high (R~?0.98). Calculated timing errors between MOG and pulse-gating RR intervals were low (~?20 ms). First insights into multidimensional fetal blood flows were achieved. Inter-subject consistency in fetal descending aortic flows (n =?3) was strong with an average velocity of 27.1?±?0.4 cm/s, peak systolic velocity of 70.0?±?1.8 cm/s and an intra-class correlation coefficient of 0.95 between the velocity waveforms. In one fetal case, high flow waveform reproducibility was demonstrated in the ascending aorta (R =?0.97) and main pulmonary artery (R =?0.99).

Conclusion

Multidimensional PC-CMR of fetal flow was developed and validated, incorporating retrospective motion compensation and cardiac gating. Using this method, the first quantification and visualization of multidimensional fetal blood flow was achieved using CMR.
  相似文献   
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To address shortcomings of purely reaction-time based attention bias modification (ABM) paradigms, a novel eye-tracking based ABM training (ET-ABM) was developed. This training targets the late disengagement from negative stimuli and the lack of attention for positive information, which are characteristics of depression. In the present study, 75 dysphoric students (BDI?≥?9) were randomly assigned to either this positive training (PT), or a sham-training (ST) that did not train any valence-specific gaze pattern (positive and negative pictures had to be disengaged from and attended to equally often). Results showed that the PT induced a positive attentional bias (longer fixations of positive than negative pictures). Although the ST group showed an increase in positive attentional bias as well, this increase was not as strong as in the PT group. Compared to the ST, the PT specifically induced faster disengagement from negative pictures. No differential training effects were found on stress responses or state rumination. These results show that the ET-ABM successfully modifies attentional processes, specifically late disengagement from negative stimuli, in dysphoric students, and hence might be a promising alternative to existing ABM paradigms.  相似文献   
128.
Reporting of hospital adverse events relies on Patient Safety Indicators (PSIs) using International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) codes. The US transition to ICD-10-CM in 2015 could result in erroneous comparisons of PSIs. Using the General Equivalent Mappings (GEMs), we compared the accuracy of ICD-9-CM coded PSIs against recommended ICD-10-CM codes from the Centers for Medicaid/Medicare Services (CMS). We further predict their impact in a cohort of 38 644 patients (1 446 581 visits and 399 hospitals). We compared the predicted results to the published PSI related ICD-10-CM diagnosis codes. We provide the first report of substantial hospital safety reporting errors with five direct comparisons from the 23 types of PSIs (transfusion and anesthesia related PSIs). One PSI was excluded from the comparison between code sets due to reorganization, while 15 additional PSIs were inaccurate to a lesser degree due to the complexity of the coding translation. The ICD-10-CM translations proposed by CMS pose impending risks for (1) comparing safety incidents, (2) inflating the number of PSIs, and (3) increasing the variability of calculations attributable to the abundance of coding system translations. Ethical organizations addressing ‘data-, process-, and system-focused’ improvements could be penalized using the new ICD-10-CM Agency for Healthcare Research and Quality PSIs because of apparent increases in PSIs bearing the same PSI identifier and label, yet calculated differently. Here we investigate which PSIs would reliably transition between ICD-9-CM and ICD-10-CM, and those at risk of under-reporting and over-reporting adverse events while the frequency of these adverse events remain unchanged.  相似文献   
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Purpose: The purpose of this study is to psychometrically test the Evaluation of Daily Activity Questionnaire in seven musculoskeletal conditions.

Materials and methods: One thousand and two hundred people with ankylosing spondylitis; osteoarthritis; systemic lupus erythematosus; systemic sclerosis; chronic pain; chronic upper limb disorders; or Primary Sjögren’s syndrome completed the Evaluation of Daily Activity Questionnaire, Health Assessment Questionnaire and Short-Form Health Survey v2. We examined internal construct validity using Rasch analysis, internal consistency, concurrent validity with the Health Assessment Questionnaire and Short-Form Health Survey v2. Participants repeated the Evaluation of Daily Activity Questionnaire to assess test–retest reliability.

Results: The 12 domains satisfied Rasch model expectations for fit, local dependency, unidimensionality and invariance by age and gender, in each musculoskeletal condition. Internal consistency was consistent with individual use (Cronbach’s α?>?0.90); concurrent validity was strong (Health Assessment Questionnaire:?rs?=?0.60–0.92; Short-Form Health Survey v2 Physical Function:?rs?=??0.61 to ?0.91) and test–retest reliability excellent (Intra-Class Correlation Coefficient(2,1)?=?0.77–0.96).

Conclusion: The Evaluation of Daily Activity Questionnaire satisfied Rasch model requirements for construct validity and has good reliability and validity in each MSC. The Evaluation of Daily Activity Questionnaire can be used as a measure of everyday activity in practice and research with people with musculoskeletal conditions.
  • Implications for rehabilitation
  • The Evaluation of Daily Activity Questionnaire evaluates users’ ability to perform common daily activities (in 12 domains) that were identified as problematic by people with seven musculoskeletal conditions (i.e., osteoarthritis, systemic lupus, ankylosing spondylitis, chronic pain, chronic upper limb conditions, systemic sclerosis, Sjogren’s syndrome).

  • Most patients considered the Evaluation of Daily Activity Questionnaire was the right length and would be helpful for discussing everyday problems with an occupational therapist.

  • The 12 domains have good reliability and validity and can be combined into two components: Self-Care and Mobility.

  • The Evaluation of Daily Activity Questionnaire is suitable for use both in clinical practice and research and a User Manual is available for therapists and researchers.

  相似文献   
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