The late pre-Hispanic period in the US Southwest (A.D. 1200–1450) was characterized by large-scale demographic changes, including long-distance migration and population aggregation. To reconstruct ...how these processes reshaped social networks, we compiled a comprehensive artifact database from major sites dating to this interval in the western Southwest. We combine social network analysis with geographic information systems approaches to reconstruct network dynamics over 250 y. We show how social networks were transformed across the region at previously undocumented spatial, temporal, and social scales. Using well-dated decorated ceramics, we track changes in network topology at 50-y intervals to show a dramatic shift in network density and settlement centrality from the northern to the southern Southwest after A.D. 1300. Both obsidian sourcing and ceramic data demonstrate that long-distance network relationships also shifted from north to south after migration. Surprisingly, social distance does not always correlate with spatial distance because of the presence of network relationships spanning long geographic distances. Our research shows how a large network in the southern Southwest grew and then collapsed, whereas networks became more fragmented in the northern Southwest but persisted. The study also illustrates how formal social network analysis may be applied to large-scale databases of material culture to illustrate multigenerational changes in network structure.
Current models of the peopling of the higher-elevation zones of the Tibetan Plateau postulate that permanent occupation could only have been facilitated by an agricultural lifeway at ~3.6 thousand ...calibrated carbon-14 years before present. Here we report a reanalysis of the chronology of the Chusang site, located on the central Tibetan Plateau at an elevation of ~4270 meters above sea level. The minimum age of the site is fixed at ~7.4 thousand years (thorium-230/uranium dating), with a maximum age between ~8.20 and 12.67 thousand calibrated carbon-14 years before present (carbon-14 assays). Travel cost modeling and archaeological data suggest that the site was part of an annual, permanent, preagricultural occupation of the central plateau. These findings challenge current models of the occupation of the Tibetan Plateau.
Predicting debris flow runout is of major importance for hazard mitigation. Apart from topography and volume, runout distance and area depends on debris flow composition and rheology, but how is ...poorly understood. We experimentally investigated effects of composition on debris flow runout, depositional mechanisms, and deposit geometry. The small‐scale experimental debris flows were largely similar to natural debris flows in terms of flow behavior, deposit morphology, grain size sorting, channel width‐depth ratio, and runout. Deposit geometry (lobe thickness and width) in our experimental debris flows is largely determined by composition, while the effects of initial conditions of topography (i.e., outflow plain slope and channel slope and width) and volume are negligible. We find a clear optimum in the relations of runout with coarse‐material fraction and clay fraction. Increasing coarse‐material concentration leads to larger runout. However, excess coarse material results in a large accumulation of coarse debris at the flow front and enhances diffusivity, increasing frontal friction and decreasing runout. Increasing clay content initially enhances runout, but too much clay leads to very viscous flows, reducing runout. Runout increases with channel slope and width, outflow plain slope, debris flow volume, and water fraction. These results imply that debris flow runout depends at least as much on composition as on topography. This study improves understanding of the effects of debris flow composition on runout and may aid future debris flow hazard assessments.
Key Points
There is an optimum debris flow composition for maximum runout
Debris flow runout depends at least as much on composition as on topography
Deposit geometry is largely controlled by debris flow composition
Carpal tunnel release (CTR) is typically offered to symptomatic patients with electrophysiological abnormalities when night orthoses no longer prevent waking with numbness and preferably before there ...is any static numbness, weakness, or atrophy. The ability to predict the amount of symptom relief after CTR could be beneficial for managing patient expectations and, therefore, improve treatment satisfaction. Therefore, the aim of this study was to identify predictors for symptom relief after CTR and to determine their contribution to symptom relief at 6 months after surgery.
A total of 1,049 patients who underwent CTR between 2011 and 2015 at 1 of 11 Xpert Clinics in the Netherlands were asked to complete online questionnaires at intake and 3 and 6 months after surgery. Patient demographics, comorbidities, and baseline scores were considered potential predictors for the amount of symptom relief on the Boston Carpal Tunnel Questionnaire (BCTQ) score, which was the primary outcome measure.
A low score on the BCTQ at intake, a codiagnosis of a trigger finger, ulnar nerve neuropathy, trapeziometacarpal joint arthrosis, and instability or arthrosis of the wrist were associated with a smaller improvement in the BCTQ domains after a CTR at 6 months after surgery and accounted for 35% to 42% of the variance on the BCTQ domains in our multivariable regression models.
In this study, we showed that clinical severity of carpal tunnel syndrome at intake is the most important factor in estimating symptom relief after surgical treatment. Furthermore, this study contributes to a more precise understanding of the capabilities of CTR in relieving symptoms for different subgroups of patients. Results of our study can be used to manage patient expectation on symptom relief from CTR.
Prognostic II.
Growing Forced Bars Determine Nonideal Estuary Planform Leuven, J. R. F. W.; Braat, L.; Dijk, W. M. ...
Journal of geophysical research. Earth surface,
November 2018, 2018-11-00, 20181101, Volume:
123, Issue:
11
Journal Article
Peer reviewed
Open access
The planform of estuaries is often described with an ideal shape, which exponentially converges in landward direction. We show how growing topographically forced nonmigratory (i.e., anchored) bars ...determine the large‐scale estuary planform, which explains the deviations observed in the planform of natural estuaries filled with bars compared to the ideal planform. Experiments were conducted in a 20‐m long, 3‐m‐wide tilting flume, the Metronome. From a narrow, converging channel a self‐formed estuary developed characterized by multiple channels, braided bars, a meandering ebb channel, and an ebb delta. Bars hardly migrated due to the alternating current, but the bar width increased with increasing estuary width. At locations where the estuary width was narrow, major channel confluences were present, while the zones between the confluences were characterized by a higher braiding index, periodically migrating channels, and a relatively large estuary width. At the seaward boundary, confluences were forced in place by the presence of the ebb tidal delta. Between confluences, bars were topographically forced to be nonmigratory. Diversion of flow around forced midchannel bars caused bank erosion. This resulted in a planform shape with a quasiperiodic widening and narrowing at the scale of forced bars. Observations in natural systems show that major confluence locations can also be caused by inherited geology and human engineering, but otherwise the estuary outline is similarly affected by tidal bars. These observations provide a framework for understanding the evolution of tidal bar patterns and the planform shape of the estuary, which has wide implications for navigation, dredging, and ecology.
Plain Language Summary
Estuaries, which are also called river mouths, form the transition from rivers to the ocean. A common concept to describe the shape of these tidally influenced estuaries is the concept of an ideal estuary, which describes estuaries as perfectly converging channels. However, in natural systems we often observe planform shapes that deviate from this converging shape. In this article, we show with experiments in a tilting flume that estuaries without any hard boundaries (such as bedrock geology) evolve into planforms with an irregular shape rather than the perfectly converging shape. We identified a mechanism in which sand bars build up in the center of the estuary, after which the flow is diverted around the bars. This process results in local widening where tidal bars initially formed, while the estuary remains relatively narrow at zones between the bars. This mechanism helps to understand the dynamic behavior of estuaries, in which bars form valuable ecological habitat and in which channels provide access to million dollar harbors.
Key Points
Quasiperiodic estuary planforms arise from diversion of flow around forced nonmigratory midchannel bars that causes bank erosion
Self‐formed confinements separate zones in which the estuary is wider and bars are more dynamic
Confinement spacing scales with bar dimensions and estuary width in experiments and nature
Nitrification is a central process of the aquatic nitrogen cycle that controls the supply of nitrate used in other key processes, such as phytoplankton growth and denitrification. Through time series ...observation and modeling of a seasonally stratified, eutrophic coastal basin, we demonstrate that physical dilution of nitrifying microorganisms by water column mixing can delay and decouple nitrification. The findings are based on a 4-y, weekly time series in the subsurface water of Bedford Basin, Nova Scotia, Canada, that included measurement of functional (
) and phylogenetic (16S rRNA) marker genes. In years with colder winters, more intense winter mixing resulted in strong dilution of resident nitrifiers in subsurface water, delaying nitrification for weeks to months despite availability of ammonium and oxygen. Delayed regrowth of nitrifiers also led to transient accumulation of nitrite (3 to 8 μmol · kg
) due to decoupling of ammonia and nitrite oxidation. Nitrite accumulation was enhanced by ammonia-oxidizing bacteria (
) with fast enzyme kinetics, which temporarily outcompeted the ammonia-oxidizing archaea (
) that dominated under more stable conditions. The study reveals how physical mixing can drive seasonal and interannual variations in nitrification through control of microbial biomass and diversity. Variable, mixing-induced effects on functionally specialized microbial communities are likely relevant to biogeochemical transformation rates in other seasonally stratified water columns. The detailed study reveals a complex mechanism through which weather and climate variability impacts nitrogen speciation, with implications for coastal ecosystem productivity. It also emphasizes the value of high-frequency, multiparameter time series for identifying complex controls of biogeochemical processes in aquatic systems.
Reef-building crustose coralline algae (CCA) are known to facilitate the settlement and metamorphosis of scleractinian coral larvae. In recent decades, CCA coverage has fallen globally and degrading ...environmental conditions continue to reduce coral survivorship, spurring new restoration interventions to rebuild coral reef health. In this study, naturally produced chemical compounds (metabolites) were collected from two pantropical CCA genera to isolate and classify those that induce coral settlement. In experiments using four ecologically important Caribbean coral species, we demonstrate the applicability of extracted, CCA-derived metabolites to improve larval settlement success in coral breeding and restoration efforts. Tissue-associated CCA metabolites induced settlement of one coral species,
Orbicella faveolata
, while metabolites exuded by CCA (exometabolites) induced settlement of three species:
Acropora palmata
,
Colpophyllia natans
and
Orbicella faveolata
. In a follow-up experiment, CCA exometabolites fractionated and preserved using two different extraction resins induced the same level of larval settlement as the unfractionated positive control exometabolites. The fractionated CCA exometabolite pools were characterized using liquid chromatography tandem mass spectrometry, yielding 145 distinct molecular subnetworks that were statistically defined as CCA-derived and could be classified into 10 broad chemical classes. Identifying these compounds can reveal their natural prevalence in coral reef habitats and facilitate the development of new applications to enhance larval settlement and the survival of coral juveniles.
Opioid Consumption After Knee Arthroscopy Wojahn, Robert D; Bogunovic, Ljiljana; Brophy, Robert H ...
Journal of bone and joint surgery. American volume,
2018-October-3, Volume:
100, Issue:
19
Journal Article
Peer reviewed
Open access
BACKGROUND:The opioid epidemic in the United States has placed increased pressure on physicians to engage in responsible opioid prescribing practices. However, surgeons currently have little ...information to guide their postoperative prescription decision-making. The purpose of this study was to assess opioid consumption after knee arthroscopy and identify preoperative factors that may predict higher opioid usage.
METHODS:A prospective observational study of 221 patients was conducted in patients undergoing outpatient knee arthroscopy for meniscal repair, partial meniscectomy, debridement, chondroplasty, or loose body removal. Participants recorded their daily opioid consumption in a postoperative pain diary. Total opioid consumption was calculated from counts of remaining pills at the 2-week and 6-week postoperative office visits. Variables, including age, sex, body mass index, smoking status, alcohol consumption, preoperative pain severity and duration, preoperative opioid usage, Patient-Reported Outcomes Measurement Information System (PROMIS) scores, and the Connor-Davidson Resilience Scale, were evaluated for an association with opioid consumption.
RESULTS:Total opioid consumption ranged from 0 to 188 pills, with a median of 7 pills (hydrocodone 5-mg equivalents). Forty-six percent of patients took ≤5 pills, 59% took ≤10 pills, and 81% took ≤20 pills. Fifty-six percent of patients had discontinued opioid usage by the third postoperative day. Eighty-eight percent of patients had surplus opioid medication at the time of the final follow-up. Patients undergoing meniscal repair, smokers, and those taking preoperative opioids were significantly more likely to take ≥20 pills (p < 0.05).
CONCLUSIONS:The median number of pills taken after knee arthroscopy is 7, with the majority of patients consuming ≤20 pills. Meniscal repair, smoking, and preoperative opioid usage were associated with higher postoperative opioid consumption.
LEVEL OF EVIDENCE:Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
HIV nucleoside reverse transcriptase inhibitors (NRTI) can cause peripheral neuropathy that is a result of mitochondrial injury. Polymorphisms in the mitochondrial genome define haplogroups that may ...have functional implications. The objective of this study was to determine if NRTI-associated peripheral neuropathy is associated with European mitochondrial haplogroups.
Case-control study of Adult AIDS Clinical Trials Group (ACTG) study 384 and ACTG Human DNA Repository participants.
ACTG study 384 was a treatment strategy trial of antiretroviral therapy with didanosine (ddI) plus stavudine (d4T) or zidovudine plus lamivudine given with efavirenz, nelfinavir, or both. Subjects were followed for up to 3 years. Peripheral neuropathy was ascertained based on signs and symptoms. For this analysis, polymorphisms that define European mitochondrial haplogroups were characterized in a majority of ACTG 384 participants, and associations with peripheral neuropathy were assessed using logistic regression.
A total of 509 subjects were included in this analysis of whom 250 (49%) were self-identified as white, non-Hispanic. Mitochondrial haplogroup T was more frequent in subjects who developed peripheral neuropathy. Among 137 white subjects randomized to receive ddI plus d4T, 20.8% of those who developed peripheral neuropathy belonged to mitochondrial haplogroup T compared to 4.5% of control subjects (odds ratio, 5.4; 95% confidence interval, 1.4-25.1; P = 0.009). Independent predictors of peripheral neuropathy were randomization to receive ddI plus d4T, older age, and mitochondrial haplogroup T.
A common European mitochondrial haplogroup may predict NRTI-associated peripheral neuropathy. Future studies should validate this relationship, and evaluate non-European mitochondrial haplogroups and other NRTI toxicities.
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