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Despite a century of study by ecologists, recovery following disturbances (succession) is not fully understood. This book provides the first global synthesis that compares plant succession in all major terrestrial biomes and after all major terrestrial disturbances. It asks critical questions such as: Does succession follow general patterns across biomes and disturbance types? Do factors that control succession differ from biome to biome? If common drivers exist, what are they? Are they abiotic or biotic, or both? The authors provide insights on broad, generalizable patterns that go beyond site-specific studies, and present discussions on factors such as varying temporal dynamics, latitudinal differences, human-caused vs. natural disturbances, and the role of invasive alien species. This book is a must-read for researchers and students in ecology, plant ecology, restoration ecology and conservation biology. It also provides a valuable framework to aid land managers attempting to manipulate successional recovery following increasingly intense and widespread human-made disturbances.
We extend the unpublished work of Handel and Miller on the classification, up to isotopy, of endperiodic automorphisms of surfaces. We give the Handel–Miller construction of the geodesic laminations, give an axiomatic theory for pseudo-geodesic laminations, show that the geodesic laminations satisfy the axioms, and prove that pseudo-geodesic laminations satisfying our axioms are ambiently isotopic to the geodesic laminations. The axiomatic approach allows us to show that the given endperiodic automorphism is isotopic to a smooth endperiodic automorphism preserving smooth laminations ambiently isotopic to the original ones. Using the axioms, we also prove the ‘transfer theorem’ for foliations of 3-manifolds, namely that, if two depth-one foliations
are transverse to a common one-dimensional foliation
whose monodromy on the non-compact leaves of
exhibits the nice dynamics of Handel–Miller theory, then
also induces monodromy on the non-compact leaves of
exhibiting the same nice dynamics. Our theory also applies to surfaces with infinitely many ends.
Mental disorders cause high burden in adolescents, but adolescents often underutilise potentially beneficial treatments. Perceived need for and barriers to care may influence whether adolescents utilise services and which treatments they receive. Adolescents and parents are stakeholders in adolescent mental health care, but their perceptions regarding need for and barriers to care might differ. Understanding patterns of adolescent-parent agreement might help identify gaps in adolescent mental health care.
A nationally representative sample of Australian adolescents aged 13–17 and their parents (N = 2310), recruited between 2013–2014, were asked about perceived need for four types of adolescent mental health care (counselling, medication, information and skill training) and barriers to care. Perceived need was categorised as fully met, partially met, unmet, or no need. Cohen's kappa was used to assess adolescent-parent agreement. Multinomial logistic regressions were used to model variables associated with patterns of agreement.
Almost half (46.5% (s.e. = 1.21)) of either adolescents or parents reported a perceived need for any type of care. For both groups, perceived need was greatest for counselling and lowest for medication. Identified needs were fully met for a third of adolescents. Adolescent-parent agreement on perceived need was fair (kappa = 0.25 (s.e. = 0.01)), but poor regarding the extent to which needs were met (kappa = −0.10 (s.e. = 0.02)). The lack of parental knowledge about adolescents' feelings was positively associated with adolescent-parent agreement that needs were partially met or unmet and disagreement about perceived need, compared to agreement that needs were fully met (relative risk ratio (RRR) = 1.91 (95% CI = 1.19–3.04) to RRR = 4.69 (95% CI = 2.38–9.28)). Having a probable disorder was positively associated with adolescent-parent agreement that needs were partially met or unmet (RRR = 2.86 (95% CI = 1.46–5.61)), and negatively with adolescent-parent disagreement on perceived need (RRR = 0.50 (95% CI = 0.30–0.82)). Adolescents reported most frequently attitudinal barriers to care (e.g. self-reliance: 55.1% (s.e. = 2.39)); parents most frequently reported that their child refused help (38.7% (s.e. = 2.69)). Adolescent-parent agreement was poor for attitudinal (kappa = −0.03 (s.e. = 0.06)) and slight for structural barriers (kappa = 0.02 (s.e. = 0.09)).
There are gaps in the extent to which adolescent mental health care is meeting the needs of adolescents and their parents. It seems important to align adolescents' and parents' needs at the beginning and throughout treatment and to improve communication between adolescents and their parents. Both might provide opportunities to increase the likelihood that needs will be fully met. Campaigns directed towards adolescents and parents need to address different barriers to care. For adolescents, attitudinal barriers such as stigma and mental health literacy require attention.
The adage “All politics is local” in the United States is largely true. Of the United States’ 90,106 governments, 99.9% are local governments. Despite variations in institutional features, descriptive representation, and policy-making power, political scientists have been slow to take advantage of these variations. One obstacle is that comprehensive data on local politics is often extremely difficult to obtain; as a result, data is unavailable or costly, hard to replicate, and rarely updated. We provide an alternative: crowdsourcing this data. We demonstrate and validate crowdsourcing data on local politics using two different data collection projects. We evaluate different measures of consensus across coders and validate the crowd’s work against elite and professional datasets. In doing so, we show that crowdsourced data is both highly accurate and easy to use. In doing so, we demonstrate that nonexperts can be used to collect, validate, or update local data.
A 230Th/U-dated stalagmite from Hulu Cave was analyzed for δ18O, δ13C, and trace elements. A ~10-yr-resolution δ18O record, spanning 51.7–42.6 ka, revealed Dansgaard-Oeschger (DO) events 14 to 11. A similar rapid transition and synchronous timing of the onset of DO 12 is evident between the Greenland and Hulu Cave records, which suggests a common forcing mechanism of DO cycles in the North Atlantic and monsoonal region of Asia. Centennial-scale monsoonal oscillations in the cave δ18O record are indicative of hydroclimatic instability during interstadials. After removing the signals of remote moisture sources, the proportion of moisture from nearby sources is found to be higher during stadials than during interstadials. To explain this, we propose that the movement of the westerly jet is an important control on the balance of nearby and distant moisture sources in East Asia. In addition, the records of δ13C and trace element ratios, which are proxies of local environmental changes, resemble the δ18O record on the scale of DO cycles, as well as on even shorter timescales. This suggests that hydrological processes and biological activity at the cave site respond sensitively to the monsoonal changes.
Understanding the critical time of weed removal (CTWR) is necessary for designing effective weed management programs in popcorn production that do not result in yield reduction. The objective of this study was to determine the CTWR in popcorn with and without a premix of atrazine and S-metolachlor applied PRE. Field experiments were conducted at the University of Nebraska–Lincoln, South Central Agricultural Laboratory near Clay Center, NE in 2017 and 2018. The experiment was laid out in a split-plot design with PRE herbicide as the main plot and weed removal timing as the subplot. Main plots included no herbicide or atrazine/S-metolachlor applied PRE. Subplot treatments included a weed-free control, a non-treated control, and weed removal timing at V3, V6, V9, V15, and R1 popcorn growth stages and then kept weed free throughout the season. A four-parameter log-logistic function was fitted to percentage popcorn yield loss and growing degree days separately to each main plot. The number of growing degree days, when 5% yield loss was achieved, was extracted from the model and compared between main plots. The CTWR was from the V4 to V5 popcorn growth stage in absence of PRE herbicide. With atrazine/S-metolachlor applied PRE, the CTWR was delayed until V10 to V15. It is concluded that, to avoid yield loss, weeds must be controlled before the V4 popcorn growth stage when no PRE herbicide is applied, and PRE herbicide, such as atrazine/S-metolachlor in this study, can delay the CTWR until the V10 growth stage.
Research was conducted from 2013 to 2015 across three sites in Mississippi to evaluate corn response to sublethal paraquat or fomesafen (105 and 35 g ai ha−1, respectively) applied PRE, or to corn at the V1, V3, V5, V7, or V9 growth stages. Fomesafen injury to corn at three d after treatment (DAT) ranged from 0% to 38%, and declined over time. Compared with the nontreated control (NTC), corn height 14 DAT was reduced approximately 15% due to fomesafen exposure at V5 or V7. Exposure at V1 or V7 resulted in 1,220 and 1,110 kg ha−1 yield losses, respectively, compared with the NTC, but yield losses were not observed at any other growth stage. Fomesafen exposure at any growth stage did not affect corn ear length or number of kernel rows relative to the NTC. Paraquat injury to corn ranged from 26% to 65%, depending on growth stage and evaluation interval. Corn exposure to paraquat at V3 or V5 consistently caused greater injury across evaluation intervals, compared with other growth stages. POST timings of paraquat exposure resulted in corn height reductions of 13% to 50%, except at V7, which was most likely due to rapid internode elongation at that stage. Likewise, yield loss occurred after all exposure times of paraquat except PRE, compared with the NTC. Corn yield was reduced 1,740 to 5,120 kg ha−1 compared with the NTC, generally worsening as exposure time was delayed. Paraquat exposure did not reduce corn ear length, compared with the NTC, at any growth stage. However, paraquat exposure at V3 or V5 was associated with reduction of kernel rows by 1.1 and 1.7, respectively, relative to the NTC. Paraquat and fomesafen applications near corn should be avoided if conditions are conducive for off-target movement, because significant injury and yield loss can result.
Widespread and repeated use of glyphosate resulted in an increase in glyphosate-resistant (GR) weeds. This led to an urgent need for diversification of weed control programs and use of PRE herbicides with alternative sites of action. Field experiments were conducted over a 4-yr period (2015 to 2018) across three locations in Nebraska to evaluate the effects of PRE-applied herbicides on critical time for weed removal (CTWR) in GR soybean. The studies were laid out in a split-plot arrangement with herbicide regime as the main plot and weed removal timing as the subplot. The herbicide regimes used were either no PRE or premix of either sulfentrazone plus imazethapyr (350 + 70 g ai ha−1) or saflufenacil plus imazethapyr plus pyroxasulfone (26 + 70 + 120 g ai ha−1). The weed removal timings were at V1, V3, V6, R2, and R5 soybean stages, with weed-free and weedy season-long checks. Weeds were removed by application of glyphosate (1,400 g ae ha−1) or by hoeing. The results across all years and locations suggested that the use of PRE herbicides delayed CTWR in soybean. In particular, the CTWR without PRE herbicides was determined to be around the V1 to V2 (14 to 21 d after emergence [DAE]) growth stage, depending on the location and weed pressure. The use of PRE-applied herbicides delayed CTWR from about the V4 (28 DAE) stage up to the R5 (66 DAE) stage. These results suggest that the use of PRE herbicides in GR soybean could delay the need for POST application of glyphosate by 2 to 5 wk, thereby reducing the need for multiple applications of glyphosate during the growing season. Additionally, the use of PRE herbicides could provide additional modes of action needed to manage GR weeds in GR soybean.
The measurement of retained austenite is important in the analysis and quality control of asmanufactured steel components, as well as to the evaluation of components returned from service. The amounts of retained austenite are most accurately measured using x-ray diffraction techniques where the integrated area under the austenite and martensite diffraction peaks from a sample are determined. In addition to quantitative information about the amount of each phase, however, the raw x-ray diffraction data contains other information that may be useful in evaluating the condition of a steel component. The diffracting particle size of both the martensite and austenite phases, and the presence and degree of preferred orientation in both phases can be calculated from the basic four peak retained austenite x-ray scan. This information, in conjunction with knowledge of the amount of retained austenite present, may be used to determine information about variations in materials and manufacturing processes as well as changes due to service. If the residual stress in both phases is also measured, additional conclusions can be made regarding changes due to processing and service. The theoretical and experimental aspects of these measurements are reviewed data from a case history in which these types of measurements were used to determine changes due to processing and service are presented.
OBJECTIVES/SPECIFIC AIMS: To evaluate the ability of various techniques to track changes in body fluid volumes before and after a rapid infusion of saline. METHODS/STUDY POPULATION: Eight healthy participants (5M; 3F) completed baseline measurements of 1) total body water using ethanol dilution and bioelectrical impedance analysis (BIA) and 2) blood volume, plasma volume and red blood cell (RBC) volume using carbon monoxide rebreathe technique and I-131 albumin dilution. Subsequently, 30mL saline/kg body weight was administered intravenously over 20 minutes after which BIA and ethanol dilution were repeated. RESULTS/ANTICIPATED RESULTS: On average, 2.29±0.35 L saline was infused with an average increase in net fluid input-output (I/O) of 1.56±0.29 L. BIA underestimated measured I/O by −3.4±7.9%, while ethanol dilution did not demonstrate a measurable change in total body water. Carbon monoxide rebreathe differed from I-131 albumin dilution measurements of blood, plasma and RBC volumes by +0.6±2.8%, −5.4±3.6%, and +11.0±4.7%, respectively. DISCUSSION/SIGNIFICANCE OF IMPACT: BIA is capable of tracking modest changes in total body water. Carbon monoxide rebreathe appears to be a viable alternative for the I-131 albumin dilution technique to determine blood volume. Together, these two techniques may be useful in monitoring fluid status in patients with impaired fluid regulation.
Investigate short- and long-term effects of Superstorm Sandy on multiple morbidities among the elderly.
We examined emergency department visits; outpatient visits; and hospital admissions for cardiovascular disease (CVD), respiratory disease, and injury among residents residing in 8 affected counties immediately, 4 months, and 12 months following Superstorm Sandy. Control groups were defined as visits/admissions during the identical time window in the 5 years before (2007-2011) and 1 year after (2013-2014) the storm in affected and nonaffected counties in New York. We performed Poisson regression to test whether there was an association of increased visits/admissions for periods following Superstorm Sandy while controlling for covariates.
We found that the risk for CVD, respiratory disease, and injury visits/admissions was more than twice as high immediately, 4 months, and 12 months after the storm than it was in the control periods. Women were at greater risk at all time periods for CVD (risk ratio [RR], 2.04) and respiratory disease (RRs: 1.89 to 1.92). Whites had higher risk for CVD, respiratory disease, and injury than other racial groups during each period.
We observed increases in CVD, respiratory disease, and injury up to a year following Superstorm Sandy. Findings demonstrate the need to incorporate short- and long-term health effects into public health recovery. (Disaster Med Public Health Preparedness. 2019;13:28-32)
Measured nerve conduction velocity in the fibular nerve increases across the knee during hip flexion. This is due to stretching of sciatic and fibular nerves. We modeled the additional nerve length required for the sciatic nerve to course around the flexed hip, based upon distance between the hip and the sciatic nerve on magnetic resonance imaging (MRI). The median distance from the femoral head to the sciatic nerve was 41 mm. The model predicted that 64 mm of sciatic nerve is required for hip flexion. This impacts our understanding of lower limb nerve conduction studies and clinical straight leg raising tests.
Understanding control of glyphosate-resistant (GR) Palmer amaranth with multiple herbicide sites of action, including synthetic auxins, is crucial for growers to minimize GR Palmer amaranth interference with crops. Field studies in 2013 and 2014 and a greenhouse study in 2014 were conducted in Stoneville, MS, to evaluate POST control of GR Palmer amaranth with 2,4-D alone and in mixtures with glyphosate and/or glufosinate. In the greenhouse study, control of 5- and 10-cm GR Palmer amaranth was 87% with 2,4-D at 0.84 kg ae ha−1. Dry weight reduction of GR Palmer amaranth was ≥81% with 2,4-D at 0.84 kg ha−1. In field studies, mixtures of glufosinate at 0.59 kg ai ha−1 and 2,4-D at 0.56 or 1.12 kg ae ha−1 controlled 5- to 10-cm GR Palmer amaranth 87% at 28 d after treatment (DAT). Averaged across glyphosate treatments, glufosinate applied alone applied to 5- to 10-cm GR Palmer amaranth reduced dry weight at 28 DAT to 20 g m−2 from 82 g m−2 and was comparable with that following 2,4-D applied alone at 1.12 kg ae ha−1 and mixtures of glufosinate plus 2,4-D at 0.56 and 1.12 kg ae ha−1. Mixtures of 2,4-D plus glufosinate provided ≥92% control of 15- to 20-cm GR Palmer amaranth at 28 DAT. When applied to 15- to 20-cm plants, mixtures of 2,4-D plus glufosinate reduced GR Palmer amaranth density to ≤5 plants m−2 compared with 65 plants m−2 where no 2,4-D or glufosinate was applied. Glufosinate and 2,4-D are viable control options for 5- to 10-cm or 15- to 20-cm GR Palmer amaranth. However, 2,4-D did not improve GR Palmer amaranth control when added to any herbicide mixture except glyphosate and glufosinate applied to 15- to 20-cm plants at the 28 DAT evaluation.
The objective of this WSSA Weed Loss Committee report is to provide quantitative data on the potential yield loss in sugar beet due to weed interference from the major sugar beet growing areas of the United States and Canada. Researchers and extension specialists who conducted research on weed control in sugar beet in the United States and Canada provided quantitative data on sugar beet yield loss due to weed interference in their regions. Specifically, data were requested from weed control studies in sugar beet from up to 10 individual studies per calendar year over a 15-yr period between 2002 and 2017. Data collected indicated that if weeds are left uncontrolled under optimal agronomic practices, growers in Idaho, Michigan, Minnesota, Montana, Nebraska, North Dakota, Ontario, Oregon, and Wyoming would potentially lose an average of 79%, 61%, 66%, 68%, 63%, 75%, 83%, 78%, and 77% of the sugar beet yield. The corresponding monetary loss would be approximately US$234, US$122, US$369, US$43, US$40, US$211, US$12, US$14, and US$32 million, respectively. The average yield loss due to weed interference for the primary sugar beet growing areas of North America was estimated to be 70%. Thus, if weeds are not controlled, growers in the United States would lose approximately 22.4 million tonnes of sugar beet yield valued at approximately US$1.25 billion, and growers in Canada would lose approximately 0.5 million tonnes of sugar beet yield valued at approximately US$25 million. The high return on investment in weed management highlights the importance of continued weed science research for sustaining high crop yield and profitability of sugar beet production in North America.
Facial nerve paresis is rare following cochlear implantation. Mechanisms underlying delayed-onset facial paresis are poorly understood. This paper describes the case of a patient who developed facial nerve paresis three years after implantation. A literature review was performed with the aim of identifying any similar cases.
The patient case is reported, and the literature reviewed using PubMed, Embase and Ovid databases.
The literature review revealed that the vast majority of delayed-onset facial nerve paresis cases occur within the first month of implantation. Only two other cases occurring years after device implantation were identified. Although potential causative factors have been suggested, as in our case this phenomenon may be idiopathic.
Prognosis for recovery of late-onset facial nerve paresis seems promising, despite the unfortunate requirement for device explantation in all previous cases including our own.