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Extant Neotropical rainforests are well known for their remarkable diversity of fruit and seed types. Biotic agents disperse most of these disseminules, whereas wind dispersal is less common. Although wind-dispersed fruits and seeds are greatly overshadowed in closed rainforests, many important families in the Neotropics (e.g., Bignoniaceae, Fabaceae, Malvaceae, Orchidaceae, Sapindaceae) show numerous morphological adaptations for anemochory (i.e. wings, accessory hairs). Most of these living groups have high to moderate levels of plant diversity in the upper levels of the canopy. Little is known about the fossil record of wind-dispersed fruits and seeds in the Neotropics. Six new species of disseminules with varied adaptations for wind dispersal are documented here. These fossils, representing extinct genera of Ulmaceae, Malvaceae, and some uncertain families, indicate that wind-dispersed fruit and seed syndromes were already common in the Neotropics by the Paleocene, coinciding with the early development of multistratal rainforests. Although the major families known to include most of the wind-dispersed disseminules in extant rainforests are still missing from the Paleogene fossil record of South and Central America, the new fossils imply that anemochory was a relatively important product and/or mechanism of plant evolution and diversification in early Neotropical rainforests.

Morphology and anatomy of the extinct angiosperm fruit, Porosia verrucosa (Lesqueruex) Hickey, are documented in detail based on various modes of preservation including molds, casts, and permineralizations from more than seventy localities in the late Cretaceous and Paleocene. The fruits are schizocarpic with paired unilocular, single-seeded mericarps seated on a prominent gynophore with an hypogynous perianth borne on a long pedicel. The most distinctive feature of these fruits is the regularly spaced cylindrical intrusions over the surface of the endocarp. These are interpreted to represent oil cavities similar to those common in the fruits of extant Rutaceae. The oldest known occurrences of P. verrucosa are from the Late Cretaceous (Campanian to Maastrichtian) of western North America, but the genus traversed Beringia and became widespread in the Paleocene both in Asia (Kazakhstan, Amur Region, and Koryak Highlands), and North America (Montana, North Dakota, Wyoming, Colorado, Oregon, Washington, Alberta, Saskatchewan). It extended to the late Paleocene in the Rocky Mountain and Great Plains region, and appears to have become extinct near the Paleocene-Eocene boundary.

Abstract Background The Ampelopsis clade (Ampelopsis and its close allies) of the grape family Vitaceae contains ca. 43 species disjunctly distributed in Asia, Europe, North America, South America, Africa, and Australia, and is a rare example to study both the Northern and the Southern Hemisphere intercontinental disjunctions. We reconstruct the temporal and spatial diversification of the Ampelopsis clade to explore the evolutionary processes that have resulted in their intercontinental disjunctions in six continents. Results The Bayesian molecular clock dating and the likelihood ancestral area analyses suggest that the Ampelopsis clade most likely originated in North America with its crown group dated at 41.2 Ma (95% HPD 23.4 - 61.0 Ma) in the middle Eocene. Two independent Laurasian migrations into Eurasia are inferred to have occurred in the early Miocene via the North Atlantic land bridges. The ancestor of the Southern Hemisphere lineage migrated from North America to South America in the early Oligocene. The Gondwanan-like pattern of intercontinental disjunction is best explained by two long-distance dispersals: once from South America to Africa estimated at 30.5 Ma (95% HPD 16.9 - 45.9 Ma), and the other from South America to Australia dated to 19.2 Ma (95% HPD 6.7 - 22.3 Ma). Conclusions The global disjunctions in the Ampelopsis clade are best explained by a diversification model of North American origin, two Laurasian migrations, one migration into South America, and two post-Gondwanan long-distance dispersals. These findings highlight the importance of both vicariance and long distance dispersal in shaping intercontinental disjunctions of flowering plants.

Background: Imaging-guided percutaneous coronary intervention (PCI) is associated with better clinical outcomes than angiography-guided PCI. Whether routine optical coherence tomography (OCT) guidance in PCI of lesions involving coronary-artery branch points (bifurcations) improves clinical outcomes as compared with angiographic guidance is uncertain., Methods: We conducted a multicenter, randomized, open-label trial at 38 centers in Europe. Patients with a clinical indication for PCI and a complex bifurcation lesion identified by means of coronary angiography were randomly assigned in a 1:1 ratio to OCT-guided PCI or angiography-guided PCI. The primary end point was a composite of major adverse cardiac events (MACE), defined as death from a cardiac cause, target-lesion myocardial infarction, or ischemia-driven target-lesion revascularization at a median follow-up of 2 years., Results: We assigned 1201 patients to OCT-guided PCI (600 patients) or angiography-guided PCI (601 patients). A total of 111 patients (18.5%) in the OCT-guided PCI group and 116 (19.3%) in the angiography-guided PCI group had a bifurcation lesion involving the left main coronary artery. At 2 years, a primary end-point event had occurred in 59 patients (10.1%) in the OCT-guided PCI group and in 83 patients (14.1%) in the angiography-guided PCI group (hazard ratio, 0.70; 95% confidence interval, 0.50 to 0.98; P = 0.035). Procedure-related complications occurred in 41 patients (6.8%) in the OCT-guided PCI group and 34 patients (5.7%) in the angiography-guided PCI group., Conclusions: Among patients with complex coronary-artery bifurcation lesions, OCT-guided PCI was associated with a lower incidence of MACE at 2 years than angiography-guided PCI. (Funded by Abbott Vascular and others; OCTOBER ClinicalTrials.gov number, NCT03171311.)., (Copyright © 2023 Massachusetts Medical Society.)

Background: The rate of carotid plaque progression is believed to be related to blood flow hemodynamics and shear stress. Our objective was to determine if wall shear rate (WSR) and the energy loss coefficient (ELC) measured by Doppler ultrasound could predict atherosclerotic carotid disease progression. Patients and methods: The average annual progression rate for the 74 plaques included was 5.7% NASCET per year. We identified 18 plaques with ≥10% NASCET progression and 56 plaques without significant progression <10% NASCET. Among the plaques with progression, only four plaques had progression greater than 20% NASCET. Median WSR was 6266 s Results: [5813-8974] in plaques with progression and 6564 s -1 [5813-8974] in plaques with progression and 6564 s -1 [5285-8766] in stable plaques (p=0.643). Median ELC was 3.86 m 2 [2.78-5.53] in plaque with progression and 4.32 m 2 [3.42-6.81] in stable plaques (p=0.296). Conclusions: Although it is a widely accepted hypothesis that shear stress and hemodynamics of the carotid bifurcation contribute to plaque progression, we found that WSR and ELC estimated by Doppler ultrasound do not reliably predict atherosclerotic plaque progression in the carotid artery. Other ultrasound modalities, such as 3D imaging, may be used to assess the influence of plaque geometry and hemodynamics in plaque progression.

Fossil discoveries can transform our understanding of plant diversification over time and space. Recently described fossils in many plant families have pushed their known records farther back in time, pointing to alternative scenarios for their origin and spread. Here, we describe two new Eocene fossil berries of the nightshade family (Solanaceae) from the Esmeraldas Formation in Colombia and the Green River Formation in Colorado (USA). The placement of the fossils was assessed using clustering and parsimony analyses based on 10 discrete and five continuous characters, which were also scored in 291 extant taxa. The Colombian fossil grouped with members of the tomatillo subtribe, and the Coloradan fossil aligned with the chili pepper tribe. Along with two previously reported early Eocene fossils from the tomatillo genus, these findings indicate that Solanaceae were distributed at least from southern South America to northwestern North America by the early Eocene. Together with two other recently discovered Eocene berries, these fossils demonstrate that the diverse berry clade and, in turn, the entire nightshade family, is much older and was much more widespread in the past than previously thought., (© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.)

Objective: Duplex ultrasonography is the reference standard for diagnosing chronic venous insufficiency. Bilateral venous reflux ultrasound studies are among the most time-consuming and physically demanding tests for vascular ultrasound technologists to perform. Furthermore, if a venous procedure is required, many insurance policies require that a diagnostic venous ultrasound scan for reflux must be performed within 1 year of the procedure. If the intervention is scheduled for >1 year after the ultrasound scan, the insurance company might require a repeat venous ultrasound scan before granting insurance authorization. Hence, ordering bilateral venous duplex ultrasound scans to evaluate for reflux when an intervention might only be performed on one limb within the year could be a waste of time and resources. The aim of the present study was to determine the utility of ordering bilateral vs unilateral studies to evaluate for reflux in patients with suspected chronic venous insufficiency and to determine whether a resource-saving potential exists for vascular laboratories through optimization of the process of ordering venous duplex ultrasound studies., Methods: A retrospective review of all patients who had undergone bilateral lower extremity ultrasound scanning to evaluate for reflux from January 1, 2016 to December 31, 2016 at the Massachusetts General Hospital vascular laboratory was performed. The demographics, indications for ultrasound scanning, comorbidities, time required to perform the ultrasound study, and interval to intervention were documented. The data were analyzed using SPSS statistical software (IBM Corp, Armonk, NY)., Results: During the study period, 13,854 ultrasound studies had been performed in our vascular laboratory, of which 606 (4.4%) had been bilateral ultrasound scans for venous insufficiency. The time allotted for a bilateral study was 2 hours. Of the 606 studies evaluated, 152 (25.1%) showed no evidence of reflux, 284 (46.9%) showed bilateral lower extremity reflux, and 170 (28.1%) showed only venous insufficiency in one leg. Venous ablation, phlebectomy, and/or sclerotherapy were performed for 28.7% of the patients. However only 6.2% of patients had undergone venous procedures on both legs within 1 year after the ultrasound studies. Ablation was the most common procedure performed (54.6%), followed by phlebectomy (27.%) and sclerotherapy (17.9%). Overall, 94.7% of patients had not undergone a venous procedure on both legs within 1 year after the ultrasound studies and, hence, would have required a repeat duplex ultrasound scan to ensure insurance coverage for future procedures., Conclusions: Most bilateral ultrasound scans for venous insufficiency will not result in an intervention. Thus, most patients (95%) could have undergone a unilateral scan before the initial intervention instead of bilateral duplex ultrasound scanning., (Copyright © 2021 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: There are no societal ultrasound (US) guidelines detailing appropriate patient selection for deep vein thrombosis (DVT) imaging in patients with COVID-19, nor are there protocol recommendations aimed at decreasing exposure time for US technologists. We aimed to provide COVID-19-specific protocol optimization recommendations limiting US technologist exposure while optimizing patient selection., Methods: A novel two-pronged algorithm was implemented to limit the DVT US studies on patients with COVID-19 prospectively, which included direct physician communication with the care team and a COVID-19-specific imaging protocol was instated to reduce US technologist exposure. To assess the pretest risk of DVT, the sensitivity and specificity of serum d-dimer in 500-unit increments from 500 to 8000 ng/mL and a receiver operating characteristic curve to assess performance of serum d-dimer in predicting DVT was generated. Rates of DVT, pulmonary embolism, and scan times were compared using t-test and Fisher's exact test (before and after implementation of the protocol)., Results: Direct physician communication resulted in cancellation or deferral of 72% of requested examinations in COVID-19-positive patients. A serum d-dimer of >4000 ng/mL yielded a sensitivity of 80% and a specificity of 70% (95% confidence interval, 0.54-0.86) for venous thromboembolism. Using the COVID-19-specific protocol, there was a significant (50%) decrease in the scan time (P < .0001) in comparison with the conventional protocol., Conclusions: A direct physician communication policy between imaging physician and referring physician resulted in deferral or cancellation of a majority of requested DVT US examinations. An abbreviated COVID-19-specific imaging protocol significantly decreased exposure time to the US technologist., (Copyright © 2020 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Engineering control of metabolic pathways is important to improving product titers and yields. Traditional methods such as overexpressing pathway enzymes and deleting competing ones are restricted by the interdependence of metabolic reactions and the finite nature of cellular resources. Here, we developed a metabolite valve that controls glycolytic flux through central carbon metabolism in Saccharomyces cerevisiae. In a Hexokinase 2 and Glucokinase 1 deleted strain (hxk2Δglk1Δ), glucose flux was diverted away from glycolysis and into a model pathway, gluconate, by controlling the transcription of Hexokinase 1 with the tetracycline transactivator protein (tTA). A maximum 10-fold decrease in hexokinase activity resulted in a 50-fold increase in gluconate yields, from 0.7% to 36% mol/mol of glucose. The reduction in glucose flux resulted in a significant decrease in ethanol byproduction that extended to semianaerobic conditions, as shown in the production of isobutanol. This proof-of-concept is one of the first demonstrations in S. cerevisiae of dynamic redirection of glucose from glycolysis and into a heterologous pathway.

Background: Children in care often have poor outcomes. There is a lack of evaluative research into intervention options., Aims: To examine the efficacy of Multidimensional Treatment Foster Care for Adolescents (MTFC-A) compared with usual care for young people at risk in foster care in England., Method: A two-arm single (assessor) blinded randomised controlled trial (RCT) embedded within an observational quasi-experimental case-control study involving 219 young people aged 11-16 years (trial registration: ISRCTN 68038570). The primary outcome was the Child Global Assessment Scale (CGAS). Secondary outcomes were ratings of educational attendance, achievement and rate of offending., Results: The MTFC-A group showed a non-significant improvement in CGAS outcome in both the randomised cohort (n = 34, adjusted mean difference 1.3, 95% CI -7.1 to 9.7, P = 0.75) and in the trimmed observational cohort (n = 185, adjusted mean difference 0.95, 95% CI -2.38 to 4.29, P = 0.57). No significant effects were seen in secondary outcomes. There was a possible differential effect of the intervention according to antisocial behaviour., Conclusions: There was no evidence that the use of MTFC-A resulted in better outcomes than usual care. The intervention may be more beneficial for young people with antisocial behaviour but less beneficial than usual treatment for those without.

Although Rhamnaceae are distributed worldwide today, the former hypothesis for its Laurasian origins may need to be reconsidered in view of recently discovered fossils from the Guaduas Formation of central Colombia (∼68 Ma), including fossil leaves (Berhamniphyllum) and a fruit (Archaeopaliurus boyacensis). Recent phylogenetic studies calibrate the stem of Rhamnaceae at 64 Ma and divide the family into three groups, rhamnoid, ampeloziziphoid, and ziziphoid. Although the fruit, Archaeopaliurus boyacensis, resembles that of Paliurus and suggests a relationship to the Paliureae in the ziziphoid group, associated leaves of Berhamniphyllum conform in architecture to those found today only in the Rhamneae tribe. The Maastrichtian age of these fossils predates the ages previously estimated for the Rhamneae tribe (28.5 Ma) and the Paliureae tribe (31.6 Ma) using a modified clock approach. Based on the new megafossil evidence, two alternative ideas are proposed: (1) that these fossils predate the extant tribes or (2) that the family diversified into modern tribes earlier than previously proposed.

The projected increase in the use of compact fluorescent lamps (CFLs) motivates the development of methods to manage consumer exposure to mercury and its environmental release at the end of lamp life. This work characterizes the time-resolved release of mercury vapor from broken CFLs and from underlying substrates after removal of glass fragments to simulate cleanup. In new lamps, mercury vapor is released gradually in amounts that reach 1.3 mg or 30% of the total lamp inventory after four days. Similar time profiles but smaller amounts are released from spent lamps or from underlying substrates. Nanoscale formulations of S, Se, Cu, Ni, Zn, Ag, and WS2 are evaluated for capture of Hg vapor under these conditions and compared to conventional microscale formulations. Adsorption capacities range over 7 orders of magnitude, from 0.005 (Zn micropowder) to 188 000 microg/g (unstabilized nano-Se), depending on sorbent chemistry and particle size. Nanosynthesis offers clear advantages for most sorbent chemistries. Unstabilized nano-selenium in two forms (dry powder and impregnated cloth) was successfully used in a proof-of-principle test for the in situ, real-time suppression of Hg vapor escape following CFL fracture.

A set of carbon materials was treated by a choice of common oxidizers to investigate the mercury capture capacities at varying temperature conditions. It was found that ozone treatment dramatically increases the mercury capture capacity of carbon surfaces by factors up to 134, but the activity is easily destroyed by exposure to the atmosphere, to water vapor, or by mild heating. Freshly ozone-treated carbon surfaces are shown to oxidize iodide to iodine in solution and this ability fades with aging. FTIR analysis shows broad C-O stretch features from 950 to 1300 cm(-1), which decay upon atmospheric exposure and are similar to the C-O-C asymmetric stretch features of ethylene secondary ozonide. The combined results suggest that the ultra-high mercury capture efficiency is due to a subset of labile C-O functional groups with residual oxidizing power that are likely epoxides or (epoxide-containing) secondary ozonides. The results open the possibility for in situ ozonolysis to create high-performance carbon-based Hg sorbents.

The fossil record of Dipteronia, the sister genus of Acer, is reviewed based on diagnostic winged fruits from the Tertiary of western North America. Today the genus is endemic to eastern Asia with two extant species in central and southern China, but it is well represented in the Tertiary of western North America, ranging from the Paleocene to the Oligocene with the greatest number of occurrences in the middle to late Eocene. There are no known fossil occurrences outside of North America. The fossil fruits, assigned to the new species D. brownii sp. nov., are smaller than those of both living species and were tricarpellate as well as bicarpellate in contrast to the modern species, which are almost exclusively bicarpellate. The tricarpellate condition may be plesiomorphic for Dipteronia and perhaps Aceroideae. The area of origin for Dipteronia is unknown, but it seems likely to have been either Asia or North America, with the genus crossing Beringia in the Paleogene.

The new genus Landeenia is recognized on the basis of flowers, pollen, infructescences, fruits, and seeds from the middle Eocene of southwestern and northwestern Wyoming. Landeenia aralioides (MacGinitie) comb.nov. has cymose inflorescences with actinomorphic, bisexual flowers, a pentamerous calyx, about ten stamens, and a superior gynoecium of ∼18 carpels sharing a single style. The fruits are globose to oblate, loculicidally dehiscent capsules, with a persistent calyx, and contain flat, elliptical seeds that are surrounded by a small wing. Pollen removed from the anthers is tricolpate with finely striate sculpture. Although clearly dicotyledonous, the combination of characters found in Landeenia is not known in any modern genus. The familial affinities of the plant, though certainly not with the Araliaceae as previously thought, remain uncertain. However, the combination of characters is consistent with treatment as a member of the Sapindales. The fossil material is thus assigned to the rank of Sapindales-Incertae sedis.

Sequence data of the chloroplast gene rbcL were used to estimate the time of the well-known eastern Asian-eastern North American floristic disjunction. Sequence divergence of rbcL was examined for 22 species of 11 genera (Campsis, Caulophyllum, Cornus, Decumaria, Liriodendron, Menispermum, Mitchella, Pachysandra, Penthorum, Podophyllum, and Phryma) representing a diverse array of flowering plants occurring disjunctly in eastern Asia and eastern North America. Divergence times of putative disjunct species pairs were estimated from synonymous substitutions, using rbcL molecular clocks calibrated for Cornus. Relative rate tests were performed to assess rate constancy of rbcL evolution among lineages. Corrections of estimates of divergence times for each species pair were made based on rate differences of rbcL between Cornus and other species pairs. Results of these analyses indicate that the time of divergence of species pairs examined ranges from 12.56 +/- 4.30 million years to recent (<0.31 million years), with most within the last 10 million years (in the late Miocene and Pliocene). These results suggest that the isolation of most morphologically similar disjunct species in eastern Asia and eastern North America occurred during the global climatic cooling period that took place throughout the late Tertiary and Quaternary. This estimate is closely correlated with paleontological evidence and in agreement with the hypothesis that considers the eastern Asian-eastern North American floristic disjunction to be the result of the range restriction of a once more or less continuously distributed mixed mesophytic forest of the Northern Hemisphere that occurred during the late Tertiary and Quaternary. This implies that in most taxa the disjunction may have resulted from vicariance events. However, long-distance dispersal may explain the disjunct distribution of taxa with low divergence, such as Menispermum., (Copyright 2000 Academic Press.)