bluuebunny/crossref_metadata_2025 huggingface dataset:
A category theoretical interpretation of discretization in Galerkin finite element method
Authors: Lahtinen Valtteri , Stenvall Antti
Published: January 2020

The Galerkin finite element method (FEM) is used widely in finding approximative solutions to field problems in engineering and natural sciences. When utilizing FEM, the field problem is said to be discretized. In this paper, we interpret discretization in FEM through category theory, unifying the concept of discreteness in FEM with that of discreteness in other fields of mathematics, such as topology. This reveals structural properties encoded in this concept: we propose that discretization is a dagger mono with a discrete domain in the category of Hilbert spaces made concrete over the category of vector spaces. Moreover, we discuss parallel decomposability of discretization, and through examples, connect it to different FEM formulations and choices of basis functions.
Probing antibody surface density and analyte antigen incubation time as dominant parameters influencing the antibody-antigen recognition events of a non-faradaic and diffusion-restricted electrochemical immunosensor
Authors: Zorea Jonathan , Shukla Rajendra P. , Elkabets Moshe , Ben-Yoav Hadar
Published: January 2020

Electrochemical sensors based on antibody-antigen recognition events are commonly used for the rapid, label-free, and sensitive detection of various analytes. However, various parameters at the bioelectronic interface, i.e., before and after the probe (such as an antibody) assembly onto the electrode, have a dominant influence on the underlying detection performance of analytes (such as an antigen). In this work, we thoroughly investigate the dependence of the bioelectronic interface characteristics on parameters that have not been investigated in depth: the antibody density on the electrode’s surface and the antigen incubation time. For this important aim, we utilized the sensitive non-faradaic electrochemical impedance spectroscopy method. We showed that as the incubation time of the antigen-containing drop solution increased, a decrease was observed in both the solution resistance and the diffusional resistance with reflecting boundary elements, as well as the capacitive magnitude of a constant phase element, which decreased at a rate of 160 ± 30 kΩ/min, 800 ± 100 mΩ/min, and 520 ± 80 pF × s(α-1)/min, respectively. Using atomic force microscopy, we also showed that high antibody density led to thicker electrode coating than low antibody density, with root-mean-square roughness values of 2.2 ± 0.2 nm versus 1.28 ± 0.04 nm, respectively. Furthermore, we showed that as the antigen accumulated onto the electrode, the solution resistance increased for high antibody density and decreased for low antibody density. Finally, the antigen detection performance test yielded a better limit of detection for low antibody density than for high antibody density (0.26 μM vs 2.2 μM). Overall, we show here the importance of these two factors and how changing one parameter can drastically affect the desired outcome.
Normalized Solutions of Nonautonomous Kirchhoff Equations: Sub- and Super-critical Cases
Authors: Chen Sitong , Rădulescu Vicenţiu D. , Tang Xianhua
Published: January 2020

In this paper, we establish the existence of normalized solutions to the following Kirchhoff-type equation $$\begin{aligned} \left\{ \begin{array}{ll} -\left( a+b\int _{{\mathbb {R}}^3}|\nabla u|^2{\mathrm {d}}x\right) \Delta u-\lambda u=K(x)f(u), &{} x\in {\mathbb {R}}^3; \\ u\in H^1({\mathbb {R}}^3), \end{array} \right. \end{aligned}$$

-

a
+
b

∫

R

3

|
∇
u
|

2

d
x

Δ
u
-
λ
u
=
K

(
x
)

f

(
u
)

,

x
∈

R

3

;

u
∈

H
1

(

R

3

)

,

where $$a, b> 0$$

a
,
b
>
0

, $$\lambda $$
λ
is unknown and appears as a Lagrange multiplier, $$K\in {\mathcal {C}}({\mathbb {R}}^3, {\mathbb {R}}^+)$$

K
∈
C
(

R

3

,

R

+

)

with $$0<\lim _{|y|\rightarrow \infty }K(y)\le \inf _{{\mathbb {R}}^3} K$$

0
<

lim

|
y
|
→
∞

K

(
y
)

≤

inf

R

3

K

, and $$f\in {\mathcal {C}}({\mathbb {R}},{\mathbb {R}})$$

f
∈
C
(
R
,
R
)

satisfies general $$L^2$$

L
2

-supercritical or $$L^2$$

L
2

-subcritical conditions. We introduce some new analytical techniques in order to exclude the vanishing and the dichotomy cases of minimizing sequences due to the presence of the potential K and the lack of the homogeneity of the nonlinearity f. This paper extends to the nonautonomous case previous results on prescribed $$L^2$$

L
2

-norm solutions of Kirchhoff problems.
Preoperative Antisepsis with Chlorhexidine Versus Povidone‐Iodine for the Prevention of Surgical Site Infection: a Systematic Review and Meta‐analysis
Authors: Chen Shi , Chen Jun Wu , Guo Bin , Xu Chun Cheng
Published: January 2020

Background and Objective

Chlorhexidine (CH) and povidone‐iodine (PI) are the most commonly used preoperative skin antiseptics at present. However, the prevention of the surgical site infection (SSI) and the incidence of skin adverse events do not reach a consistent statement and conclusion. This meta‐analysis aimed to evaluate the efficacy of chlorhexidine and povidone‐iodine in the prevention of postoperative surgical site infection and the incidence of corresponding skin adverse events.

Method

Substantial studies related to “skin antiseptic” and “surgical site infection” were consulted on PUBMED, Web of Science, EMBASE, and CNKI. The primary outcome was the incidence of postoperative SSI. The secondary outcome was associated with skin adverse events. All data were analyzed with Revman 5.3 software.

Results

A total of 30 studies were included, including 29,006 participants. This study revealed that chlorhexidine was superior to povidone‐iodine in the prevention of postoperative SSI (risk ratio [RR], 0.65; 95% confidence interval [CI], 0.55–0.77; p < 0.00001, I2 = 57%). Further subgroup analysis showed that chlorhexidine was superior to povidone‐iodine in the prevention of postoperative SSI in clean surgery (risk ratio [RR], 0.81; 95% confidence interval [CI], 0.67–0.98; p = 0.03), I2 = 28%) and clean‐contaminated surgery (risk ratio [RR], 0.58; 95% confidence interval [CI], 0.47–0.73; p < 0.00001, I2 = 43%). However, there was no statistically significant difference in the incidence of skin adverse events between CH and PI groups.

Conclusion

Chlorhexidine was superior to povidone‐iodine in preventing postoperative SSI, especially for the clean‐contaminated surgery. However, there was no statistically significant difference in the incidence of skin adverse events between CH and PI groups.
The effect of meniscal repair on strength deficits 6 months after ACL reconstruction
Authors: Wenning M. , Heitner A. H. , Mauch M. , Gehring D. , Ramsenthaler C. , Paul J.
Published: January 2020

Introduction

Ruptures of the anterior cruciate ligament (ACL) can be accompanied by meniscal lesions. Generally, the rehabilitation protocols are altered by meniscal repair. Therefore, the aim of this study was to investigate the effect of meniscal repair on the early recovery of thigh muscle strength in ACL reconstruction (ACLR).

Materials and methods

We performed a matched cohort analysis of n = 122 isolated ACLR (CON) compared to n = 61 ACLR with meniscal repair (ACLR + MR). The subgroups of meniscal repair consisted of 30 patients who had undergone medial meniscus repairs (MM), 19 lateral meniscus repairs (LM) and 12 repairs of medial and lateral meniscus (BM). Isokinetic strength measurement was performed pre-operatively and 6 months post-surgery to perform a cross-sectional and a longitudinal analysis. All injuries were unilateral, and the outcome measures were compared to the non-affected contralateral leg.

Results

Six months postoperatively overall there is no significant difference between the groups (extension strength MR 82% vs. CON 85% and flexion strength 86% vs. 88%, resp.). Subgroup analysis showed that medial repairs exhibit a comparable leg symmetry while lateral repairs performed worse with leg symmetry being 76% in extension and 81% in flexion strength. Patients undergoing BM repair performed in between lateral and medial repairs (82% extension, 86% flexion).

Conclusion

Generally, meniscal repair in conjunction with ACLR does not significantly alter the recovery of limb symmetry in strength at 6 months postoperatively. Interestingly, medial repairs seem to perform superior to lateral meniscal repair and repair of both menisci. Since the recovery of symmetric strength is a major factor in rehabilitation testing, these results will help to advise surgeons on appropriate rehabilitation protocols and setting realistic goals for the injured athlete.

Level of evidence

III, retrospective cohort study.
Current clinical practice of electroconvulsive therapy and repetitive transcranial magnetic stimulation in psychiatry, a German sample
Authors: Timäus Charles , Vogelgsang Jonathan , Kis Bernhard , Radenbach Katrin , Wolff-Menzler Claus , Mavridou Kiriaki , Gyßer Stephan , Hessmann Philipp , Wiltfang Jens
Published: January 2020

The purpose of the study was to evaluate the current clinical practice of Electroconvulsive Therapy and Repetitive Transcranial Magnetic Stimulation in German psychiatry. Case-based data (> 1.000.000 cases) were collected according to §21 of the German hospital remuneration law from January 2015 to December 2017. The study cohort comprises approximately 35–40% of the annual psychiatric cases and hospitals in Germany. Frequency of ECT and rTMS cases were investigated considering main diagnoses according to ICD-10 and treatment settings (inpatient vs. day-care). ECT cases with short-term hospitalization (≤ 4 days) were supposed to be maintenance ECT cases. A linear regression analysis was conducted to estimate trends in the use of ECT and rTMS. Different groups were compared using Chi-square tests. ECT and rTMS cases appear to increase in total during the observation period possibly due to facilities newly introducing ECT and rTMS but also to increased frequency of treatments. Both treatments were rarely performed in day-care settings (0.89% and 11.25%). ECT was performed in 1.72% of all cases with affective disorders and in 1.48% with major depressions, respectively. Age ≥ 65 years, females, severe and psychotic depression were significantly associated with a higher rate of ECT cases. > 40% of all ECT cases were possibly maintenance ECT cases. Only 0.60% of these were performed in day- care settings. rTMS was primarily performed in major depression (86,7% of all rTMS cases). This study suggests a growing demand for ECT and rTMS. Nevertheless, the use of ECT is still low compared to the high prevalence of treatment resistant depression. The use of rTMS is even lower and seems to be restricted to specialized institutions. Maintenance ECT is frequently carried out in an inpatient setting. Limitations of this study are the case- and group-based analysis, missing data on outpatient services and treatment sessions per case. Therefore, the database is not necessarily representative for the entire German healthcare system. Further studies are needed to verify the presented findings and should address the feasibility of ambulatory and day-care ECT services.
Magnetic resonance tomography for the early detection of occult fractures of the spinal column in patients with ankylosing spondylitis
Authors: von der Höh Nicolas H. , Henkelmann Jeanette , Jarvers Jan-Sven , Spiegl Ulrich Josef A. , Voelker Anna , Josten Christoph , Heyde Christoph-Eckhard
Published: January 2020

Purpose

The purpose of this study was to determine the extent to which magnetic resonance imaging (MRI) performed in patients with ankylosing spondylitis (AS) after low- and no-energy trauma leads to an improved diagnosis and, as a result, to a change in the therapeutic strategy.

Methods

All patients with AS, who underwent surgery after minor traumas (low-energy traumas, LETs) and patients without trauma history (NET: no-energy trauma), were retrospectively analysed. The diagnostic and planned surgical procedure was examined initially and again after total spine MRI in patients with persistent and/or new complaints.

Results

One hundred and thirty-six patients with AS after trauma were surgically treated. A total of 92 patients with LETs and 12 patients with NETs were included. After initial diagnostics (CT and X-ray) were performed in 15.4% of the patients with LET or NET (n = 16), we found occult fractures on MRI scans. In ten of these patients (6 LET, 4 NET) in which a previous decision was made to follow conservative therapy, no fracture indication was found on CT or X-ray. Two fracture heights were observed in six patients who experienced LET. However, on X-ray and CT, the fractures were only visible at one height. All fractures were treated surgically with stabilization and decompression if indicated.

Conclusion

Considering the high percentage of our patient population with occult fractures, we recommend supplementing the basic diagnostic procedures with an MRI of the entire spinal column in patients with painful spinal column findings after minor trauma and for those with persistent pain without trauma.

Graphic abstract

These slides can be retrieved under Electronic Supplementary Material.
Sliced inverse median difference regression
Authors: Babos Stephen , Artemiou Andreas
Published: January 2020

In this paper we propose a sufficient dimension reduction algorithm based on the difference of inverse medians. The classic methodology based on inverse means in each slice was recently extended, by using inverse medians, to robustify existing methodology at the presence of outliers. Our effort is focused on using differences between inverse medians in pairs of slices. We demonstrate that our method outperforms existing methods at the presence of outliers. We also propose a second algorithm which is not affected by the ordering of slices when the response variable is categorical with no underlying ordering of its values.
Unusual blood profiles in the endemic Kagu of New Caledonia are not physiological
Authors: Gula Roman , Bloc Henri , Duval Thomas , Theuerkauf Jörn
Published: January 2020

Previous research reported a unique haematological profile in the flightless Kagu (Rhynochetos jubatus). To verify this, we analysed blood of eight wild and four captive Kagu. The haematological profiles of our captive birds resembled those of the previously studied captive Kagu. Haemoglobin concentration, mean corpuscular haemoglobin concentration and mean corpuscular haemoglobin by far exceeded the highest levels recorded for birds. Conversely, the blood profile in wild Kagu fit in the range of other birds. We conclude that blood profiles of captive Kagu indicate a pathology, and that Kagu do not have fundamentally different blood characteristic than other endothermic vertebrates.
Optimal Design for Metal Additive Manufacturing: An Integrated Computational Materials Engineering (ICME) Approach
Authors: Motaman S. Amir H. , Kies Fabian , Köhnen Patrick , Létang Maike , Lin Mingxuan , Molotnikov Andrey , Haase Christian
Published: January 2020

We present our latest results on linking the process–structure–properties–performance (PSPP) chain for metal additive manufacturing (AM), using a multi-scale and multi-physics integrated computational materials engineering (ICME) approach. The abundance of design parameters and the complex relationship between those and the performance of AM parts have so far impeded the widespread adoption of metal AM technologies for structurally critical load-bearing components. To unfold the full potential of metal AM, establishing a full quantitative PSPP linkage is essential. It will not only help in understanding the underlying physics but will also serve as a powerful and effective tool for optimal computational design. In this work, we illustrate an example of ICME-based PSPP linkage in metal AM, along with a hybrid physics-based data-driven strategy for its application in the optimal design of a component. Finally, we discuss our outlook for the improvement of each part in the computational linking of the PSPP chain.
Rapid changes in neuroendocrine regulation may contribute to reversal of type 2 diabetes after gastric bypass surgery
Authors: Katsogiannos Petros , Kamble Prasad G. , Wiklund Urban , Sundbom Magnus , Espes Daniel , Hammar Ulf , Karlsson F. Anders , Pereira Maria J. , Eriksson Jan W.
Published: January 2020

Objective

To explore the role of hormones and the autonomic nervous system in the rapid remission of diabetes after Roux-en-Y Gastric Bypass (RYGB).

Research design and methods

Nineteen obese patients with type 2 diabetes, 7 M/12 F, were randomized (2:1) to RYGB or standard-of-care medical treatment (control). At baseline and 4 and 24 weeks post surgery, fasting blood sampling, OGTT, intravenous arginine challenge, and heart-rate variability (HRV) assessments were performed.

Results

At both 4 and 24 weeks post-RYGB the following effects were found: arginine-stimulated insulin secretion was reduced. GLP-1, GIP, and glucagon rise during OGTT was enhanced. IGF-1 and GH levels increased. In addition, total HRV and spectral components PLF (power of low frequency) and PHF (power of high frequency) increased. At 4 weeks, morning cortisol was lower than baseline and 24 weeks. At 24 weeks, NEFA levels during OGTT, and the PLF/PHF ratio decreased. None of these changes were seen in the control group.

Conclusions

There were rapid changes within 4 weeks after RYGB: signs of enhanced parasympathetic nerve activity, reduced morning cortisol, and enhanced incretin and glucagon responses to glucose. The findings suggest that neurohormonal mechanisms can contribute to the rapid improvement of insulin resistance and glycemia following RYGB in type 2 diabetes.
Tetrapod swim techniques interpreted from swim trace fossils from the Lower Triassic Baranów Formation, Holy Cross Mountains, central Poland
Authors: Sadlok Grzegorz , Pawełczyk Krzysztof
Published: January 2020

Swimming tetrapods may leave their traces under water if their digits or limbs stir the bottom sediment. Resulting trace fossils are evidence of a swim behavior. Tetrapods swim techniques depend on the functional morphology of the swimmers. Examination of swim trace fossils may reveal the swim techniques employed and swimmers’ functional morphologies behind the behaviors. The present paper analyzes swim trace fossils of tetrapods from the fluvial Lower Triassic Baranów Formation in the Holy Cross Mountains (central Poland). The examination focuses on swim techniques. An attempt is made to correlate the inferred technique with functional morphology of the swimmer. It is concluded that the two types of swim traces occur in the Baranów Formation. These record two different swim techniques—paddling with limbs and body/tail undulation. The distinct types of swim trace fossils point to two types of swimmers: fully terrestrial archosaurs paddling with their limbs and amphibious tetrapods swimming with undulatory movements—likely utilizing their laterally flattened tails.
Mining trips from location-based social networks for clustering travelers and destinations
Authors: Dietz Linus W. , Sen Avradip , Roy Rinita , Wörndl Wolfgang
Published: January 2020

It is important to learn the characteristics of travelers and touristic regions when trying to generate recommendations for destinations to users. In this work, we first present a data-driven method to mine trips from location-based social networks to understand how tourists travel the world. These trips are quantified using a number of metrics to capture the underlying mobility patterns. We then present two applications that utilize the mined trips. The first one is an approach for clustering travelers in two case studies, one of Twitter and another of Foursquare, where the pure mobility metrics are enriched with social aspects, i.e., the kinds of venues into which the users checked-in. Clustering 133,614 trips from Twitter, we obtain three distinct clusters. In the Foursquare data set, however, six clusters can be determined. The second application area is the spatial clustering of destinations around the world. These discovered regions are solely formed by the mobility patterns of the trips and are, thus, independent of administrative regions such as countries. We identify 942 regions as destinations that can be directly used as a region model of a destination recommender system. This paper is the extended version of the conference article “Characterisation of Traveller Types Using Check-in Data from Location-Based Social Networks” presented at the 26th Annual ENTER eTourism Conference held from January 19 to February 1, 2019 in Nicosia, Cyprus.
Axisymmetric Wave Propagation Behavior in Fluid-Conveying Carbon Nanotubes Based on Nonlocal Fluid Dynamics and Nonlocal Strain Gradient Theory
Authors: Yang Yang , Lin Qihui , Guo Rongxin
Published: January 2020

Purpose

Goal for the present research is investigating the axisymmetric wave propagation behaviors of fluid-filled carbon nanotubes (CNTs) with low slenderness ratios when the nanoscale effects contributed by CNT and fluid flow are considered together.

Method

An elastic shell model for fluid-conveying CNTs is established based on theory of nonlocal elasticity and nonlocal fluid dynamics. The effects of stress non-locality and strain gradient at nanoscale are simulated by applying nonlocal stress and strain gradient theories to CNTs and nonlocal fluid dynamics to fluid flow inside the CNTs, respectively. The equilibrium equations of axisymmetric wave motion in fluid-conveying CNTs are derived. By solving the governing equations, the relationships between wave frequency and all small-scale parameters, as well as the effects caused by fluid flow on different wave modes, are analyzed.

Results

The numerical simulation indicates that nonlocal stress effects damp first-mode waves but promote propagation of second-mode waves. The strain gradient effect promotes propagation of first-mode waves but has no influence on second-mode waves. The nonlocal fluid effect only causes damping of second-mode waves and has no influence on first-mode waves. Damping caused by nonlocal effects are most affect on waves with short wavelength, and the effect induced by strain gradient almost promotes the propagation of wave with all wavelengths.
Interspecific competitive potential of wavyleaf basketgrass (Oplismenus undulatifolius), a recent introduction to the mid-Atlantic United States
Authors: Kepner Cody , Beauchamp Vanessa B.
Published: January 2020

Understanding the mechanisms by which an invasive plant species is able to colonize and successfully expand into native plant communities can help in estimating the potential threat posed by a new invader and predict impacts on community diversity, structure, and function. Wavyleaf basketgrass [Oplismenus undulatifolius (Ard.) P. Beauv.] is a perennial, shade-tolerant grass species that has been recently introduced to the mid-Atlantic United States. Areas invaded by O. undulatifolius typically have low species richness, but it is unknown whether O. undulatifoius actively outcompetes other species or simply thrives primarily in species-poor habitats. This study used a greenhouse experiment to quantify interspecific competition in shade and sun among seedlings of O. undulatifolius; Japanese stiltgrass [Microstegium vimineum (Trin.) A. Camus], an invasive annual grass common in the region; and a mix of three native perennial grass species commonly used in restoring areas invaded by M. vimineum. In this experiment, shade did not significantly affect growth or competitive ability. Interspecific competition irrespective of shade had a negative effect on growth of all species, but O. undulatifolius was affected to a much greater degree than either M. vimineum or the native grass mix. These results suggest that, at least under these conditions, O. undulatifolius is a weak interspecific competitor and may be capable of forming dense monotypic stands only in areas that already have low species diversity. In the mid-Atlantic region, postagricultural legacies and overabundant deer populations, which lead to depauperate understories, may be a major facilitator of O. undulatifolius invasion in forests.
Complete sporogony of the blood parasite Haemoproteus nucleocondensus in common biting midges: why is its transmission interrupted in Europe?
Authors: Žiegytė Rita , Platonova Elena , Bernotienė Rasa , Valkiūnas Gediminas , Palinauskas Vaidas
Published: January 2020

Haemoproteus species (Haemoproteidae) are widespread blood parasites and are transmitted by Culicoides biting midges and Hippoboscidae louse flies. Although these pathogens may cause morbidity or mortality, the vectors and patterns of transmission remain unknown for the great majority of avian haemoproteids. Haemoproteus nucleocondensus has been frequently reported in Europe in great reed warblers Acrocephalus arundinaceus after their arrival from African wintering grounds, but this infection has not been found in juveniles at the breeding sites. The factors that prevent its transmission remain unclear. This study was designed to test whether the sporogony of H. nucleocondensus (lineage hGRW8) can be completed in Culicoides impunctatus, one of the most abundant European biting midge species. Wild-caught females were infected with H. nucleocondensus from great reed warblers. Microscopic examination and PCR-based methods were used to detect sporogonic stages and to confirm species identity. This study showed that H. nucleocondensus completes sporogony in C. impunctatus, suggesting that there are no obstacles to its transmission from the point of view of vector availability and average temperature in Northern Europe. We discuss other ecological factors which should be considered to explain why the transmission of H. nucleocondensus and some other Southern origin haemosporidians are interrupted in North Europe.
Restoration of grazing land to increase biomass production and improve soil properties in the Blue Nile basin: effects of infiltration trenches and Chloris Gayana reseeding
Authors: Erkossa T. , Geleti D. , Williams T. O. , Laekemariam F. , Haileslassie A.
Published: January 2020

Degradation of crop and grazing lands is a pervasive problem that negatively impacts agricultural productivity and livelihoods of crop-livestock farmers in the Blue Nile basin of Ethiopia. Area enclosure together with a cut and carry livestock feeding system is often advocated as an approach for the regeneration of degraded grazing lands. This paper reports the results of a two-year farmer participatory study conducted to assess the effects of infiltration trenches (ITs) and Chloris gayana Kunth (Rhodes grass; cultivar Masaba; tetraploid; C4 grass species) reseeding on restoration of degraded grazing lands. A split plot design was used with IT as the main plot and C. gayana reseeding as a sub-plot on 28 private grazing plots under enclosure. The results showed that IT alone increased soil moisture content and prolonged the growing period. IT and C. gayana reseeding together significantly (P ≤ 0.05) increased herbage dry matter yield and improved soil chemical properties. The highest mean herbage dry matter yield (21 Mg ha−1 per cut) was recorded for plots treated with IT and reseeded with C. gayana. The higher herbage dry matter yield was attributed to increased soil moisture and the resultant prolonged growing period induced by the trenches coupled with the ability of C. gayana to effectively utilize the retained water. The results suggest that an integrated land management approach involving enclosure, in-situ water conservation and C. gayana reseeding can rapidly increase biomass productivity on degraded grazing lands while also enhancing soil quality with concomitant livelihood benefits for farmers.
Prescription opioid misuse motive latent classes: outcomes from a nationally representative US sample
Authors: Schepis Ty S. , De Nadai A. S. , Ford J. A. , McCabe S. E.
Published: January 2020

Aims

Prescription opioid misuse (POM) contributes to a larger opioid crisis in the US and Canada, with over 17 000 US POM-related overdose deaths in 2017. Our aims were to (1) identify specific profiles of respondents based on POM motives using the US National Survey on Drug Use and Health (NSDUH) and (2) compare profile respondents on sociodemographics, substance use and mental and physical health outcomes.

Methods

Analyses included 2017–18 NSDUH respondents with data on POM motives (n= 4810). POM was defined as prescription opioid use in a way not intended by the prescriber, including use without a prescription, in larger amounts or more frequently. Nine POM motives for the most recent episode were assessed, including ‘to relieve physical pain’ and ‘to get high’. Latent classes, based on POM motives, were estimated. Classes were compared on sociodemographics, substance use and physical and mental health outcomes.

Results

Eight latent classes were identified (in order of prevalence): pain relief only, relax-pain relief, sleep-pain relief, multi-motive, high, experimenter, emotional coping and dependent/hooked. Compared to the pain relief only group, the high and multi-motive classes had higher odds of all substance use outcomes, with the dependent/hooked class having higher odds on all but one outcome. Six of the eight classes had higher odds of past-year mental health treatment and suicidal ideation than the pain relief only class.

Conclusions

Screening for pain, pain conditions, problematic substance use and psychopathology are recommended in those with any POM. While those in the dependent/hooked, multi-motive and emotional coping classes are most likely to have prescription opioid use disorder (OUD), screening for OUD symptoms in all individuals with POM is also warranted.
The Response of River‐Resident Fish to Reservoir Freshet Releases of Varying Profiles Intended to Facilitate a Spawning Migration
Authors: Baker N. J. , Taylor M. J. , Cowx I. G. , Harvey J. P. , Nunn A. D. , Angelopoulos N. V. , Smith M. A. , Noble R. A. , Tinsdeall M. , Baxter J. , Bolland J. D.
Published: January 2020

Natural hydrological regimes encompass varying seasonal flow characteristics that provide fish with cues and opportunities for upstream spawning migrations, but these flows are often modified/absent in regulated rivers. Compensatory artificial flows (freshets) can be released from reservoirs to replicate these characteristics, but studies testing their effectiveness are limited. To address this, river‐resident brown trout, a species known to undertake spawning migrations, were manually tracked using radio telemetry in a regulated upland river in northern England in response to 11 freshet releases of differing timing, magnitude, and duration. Spawning migrations were not observed because extent of movement during freshets was generally small and the pattern of movement (i.e., directionality and relocation indices) was comparable between impact/control reaches. Movements during freshets were comparable with those observed the days immediately before/after and were small relative to the entire tracking period. In conclusion, freshet characteristic of those recommended to produce “naturalized” autumn/winter flow elevations did not stimulate/facilitate spawning migrations of river‐resident brown trout under the given seasonal conditions. Outside freshets, longer unidirectional movements occurred during low‐flow periods and elevated river level due to rainfall, including during periods of reservoir overtopping. Notwithstanding, fish in experimental reaches were significantly more active (total distance moved) and occupied a larger extent of river (range during freshet) than those in control reaches during short‐duration freshets. Therefore, during dry years/when (autumn/winter) reservoir overtopping events are unlikely, small‐magnitude freshets providing flows that allow fish short opportunities to search for/find superior local habitat while minimizing total water released are recommended.
Magnetic Structure of Fast‐Spread Oceanic Crust at Pito Deep
Authors: Maher S. M. , Gee J. S. , Doran A. K. , Cheadle M. J. , John B. E.
Published: January 2020

Magnetic surveys at tectonic windows that expose magnetic polarity boundaries provide the unique opportunity to explore the pattern of magnetization variations within the oceanic crust and determine the spatially averaged magnetizations of source layers that contribute to marine magnetic anomalies. Here we investigate the C2An.2n/C2An.2r polarity boundary in the tectonic window of Pito Deep, which has exposed a cross‐section through lavas, dikes, and the uppermost kilometer of gabbros at fast‐spread ocean crust. Near‐bottom magnetic anomaly surveys from two expeditions have been incorporated into a penalized least squares inversion method. The application of this method to magnetic data allows us to account for complex bathymetry and differing observation altitudes. When correlated with rock type, the magnetization solution shows median values of 4.4 ± 2.7 A/m for lavas, 2.0 ± 1.9 A/m for dikes, and 1.9 ± 1.9 A/m for gabbros. On a regional scale, lavas and dikes have a different polarity of magnetization than the underlying gabbros. The geometry of the polarity boundary is compatible with a large (~6 km) horizontal offset or very shallow dip of isotherms at the dike/gabbro boundary, and indicates that the zone of melt is significantly wider across axis than predicted from seismic tomography models that suggest pervasive cooling throughout the lower crust within a few kilometers of the spreading center.
Influence of the Thickness of the Overriding Plate on Convergence Zone Dynamics
Authors: Hertgen Solenn , Yamato Philippe , Guillaume Benjamin , Magni Valentina , Schliffke Nicholas , van Hunen Jeroen
Published: January 2020

The important role played by the upper plate in convergence zones dynamics has long been underestimated but is now more and more emphasized. However, the influence of its thickness and/or strength on orogenic systems evolution remains largely unknown. Here we present results from 3D thermo‐mechanical numerical simulations of convergence zones (including oceanic subduction followed by continental subduction/collision), in which we vary the rheological profile of the overriding plate (OP). For this, we systematically modify the crustal thickness of the overriding lithosphere and the temperature at the Moho to obtain a thermal thickness of the overriding lithosphere ranging from 80 to 180 km. While all models share a common global evolution (i.e., slab sinking, interaction between slab and the 660 km discontinuity, continental subduction/collision, and slab breakoff), they also highlight first‐order differences arising from the variations in the OP strength (thermal thickness). With a thin/weak OP, slab rollback is favored, the slab dip is low, the mantle flow above the slab is vigorous, and the trench migrates at a high rate compared to a thick/strong OP. In addition, slab breakoff and back‐arc basin formation events occur significantly earlier than in models involving a thick OP. Our models therefore highlight the major role played by the thickness/strength of the OP on convergence zone dynamics and illustrate its influence in a quantitative way.
Automated Methods for Detecting Volcanic Deformation Using Sentinel‐1 InSAR Time Series Illustrated by the 2017–2018 Unrest at Agung, Indonesia
Authors: Albino F. , Biggs J. , Yu C. , Li Z.
Published: January 2020

Radar satellites, such as Sentinel‐1, are now able to produce time series of ground deformation at any volcano around the world, but atmospheric effects still limit the real‐time detection of unrest at tropical volcanoes. Here, we test two approaches to correct atmospheric errors—phase elevation correlations and global weather models—and assess the ability of Interferometric Synthetic Aperture Radar (InSAR) time series to detect deformation anomalies using either a fixed threshold or a cumulative sum control chart. We use the 2017–2018 crisis at Agung volcano as a case example because strong atmospheric signals were originally misidentified as true deformation, and obscured the subtle deformation pattern associated with magmatic activity. We assess the Receiver Operating Characteristics (ROC) of each method and found the average area under the ROC curve to be about 0.5 for the uncorrected data (corresponding to no discrimination capability), around 0.8 after combined atmospheric corrections (weather model and phase elevation approaches), and more than 0.95 using a cumulative sum control chart (where 1 corresponds to ideal separation between classes). Our results retrospectively show that uplift could have been detected to a 95% level of confidence for both ascending and descending time series by October 2017, 15 days after the start of the seismic swarm and 1 month prior to the eruption. Thus, our approach successfully flags anomalous behavior without relying on visual inspection or selection of an arbitrary threshold, and hence shows potential as a monitoring tool for volcano observatories globally.
Plume Dynamics of a Lateral River Tributary Influenced by River Discharge From the Estuary Head
Authors: Gong Wenping , Chen Lianghong , Zhang Heng , Yuan Lirong , Chen Zhaoyun
Published: January 2020

River plumes are important pathways for the transportation of terrigenous materials to coastal oceans. This study uses the Regional Ocean Modeling System to investigate the dynamics of a small river plume from a lateral river tributary discharging into an estuary. In particular, the plume is surface advected under buoyancy force alone, and the Earth's rotation helps to increase the plume's spread in a downstream‐biased pattern. Adding tides to the model changes the plume into a bottom‐advected one, and the plume is advected in an alongshore direction, with its spreading more upstream biased. Tide‐induced mixing and tidal advection are responsible for the changes in the plume structure, especially the tidal asymmetry between ebb and flood tides; the tidal residual circulation is insignificant. When river discharge from the estuary head is imposed, the plume is forced to propagate downstream extensively. This study offers insights into the transport and fate of riverine materials in tributaries that flow into semienclosed waterbodies.
Dense GNSS Profiles Across the Northwestern Tip of the India‐Asia Collision Zone: Triggered Slip and Westward Flow of the Peter the First Range, Pamir, Into the Tajik Depression
Authors: Metzger Sabrina , Ischuk Anatoly , Deng Zhiguo , Ratschbacher Lothar , Perry Mason , Kufner Sofia‐Katerina , Bendick Rebecca , Moreno Marcos
Published: January 2020

At the northwestern tip of the India‐Asia collision zone, the Pamir orocline overrides the Tajik Depression and the Tarim Basin and collides with the Tian Shan. Currently, the Pamir's northern edge exhibits localized shortening rates of 13–19 mm/yr. While the eastern Pamir and the Tarim Basin move northward nearly en block, north‐south shortening decreases westward along the Pamir front into the Tajik Depression. In the northeastern Tajik Depression, the wedge‐shaped crustal sliver of the Peter the First Range is squeezed between the dextral‐transpressive Vakhsh and the sinistral‐transpressive Darvaz faults. Global Navigation Satellite System (GNSS) data collected along two densely surveyed profiles detail the kinematics of north‐south shortening and westward lateral extrusion in the northwestern Pamir. The 2016 campaign data suggest a short‐duration dextral‐slip activation of the Darvaz fault, which we interpret as a far‐field effect triggered by the 2015, Mw7.2 Sarez, Central Pamir earthquake. 2013–2015 interseismic GNSS velocities and kinematic modeling show that the Darvaz fault zone accommodates ~15 mm/yr sinistral shear and ~10 mm/yr fault‐normal extension below a locking depth of 9.0 + 0.4/−1.1 km. The Vakhsh fault shows shortening rates of 15 + 4/−2 mm/yr and dextral shear rates of 16 ±3 mm/yr. Jointly, these faults accommodate NW‐SE shortening and southwestward material flow out of the Peter the First Range into the Tajik Depression. Together with seismic and geologic data, our and published geodetic surveys showcase the prolonged interaction of shortening and lateral material flow out of a plateau margin.
Reconstructing the Source and Growth of the Makran Accretionary Complex: Constraints From Detrital Zircon U‐Pb Geochronology
Authors: Esmaeili R. , Xiao W. , Griffin W. L. , Moghadam H. Shafaii , Zhang Z. , Ebrahimi M. , Zhang J. , Wan B. , Ao S. , Bhandari S.
Published: January 2020

We have used U‐Pb zircon ages and Hf isotopic compositions for detrital zircons from Eocene and Cretaceous‐Triassic sedimentary rocks of the Makran accretionary complex (MAC, Iran) to understand the source and growth of the MAC during Mesozoic and Cenozoic time. The Cenozoic sandstones reveal the main age distribution from Paleocene to Eocene with a peak at 54 Ma and show εHf(t) values of −47.7 to +12.1. Our compiled U‐Pb‐Hf data from both the Urumieh‐Dokhtar Magmatic Belt magmatic zircons and the Paleogene Makran detrital zircons reveal that both Makran continental arc and Urumieh‐Dokhtar Magmatic Belt are important suppliers of the Makran detrital zircons. Mesozoic zircons show dominant peaks at 94–91 (Late Cretaceous), 151 (Late Jurassic), and 229 Ma (Triassic). Detrital zircons with peaks at 91 and 151 Ma with εHf(t) values of −42.5 to +15.2 can be supplied by the erosion of Makran ophiolitic rocks, although negative εHf(t) values indicate some Makran detrital zircons came from reworking of the magmatic rocks of the Sanandaj‐Sirjan zone of Iran. Late Cretaceous detrital zircons (~94–91 Ma) were also supplied from erosion of the nascent Makran arc. Middle to Late Jurassic zircons (163–151 Ma) can also come from erosion of the rifting‐related magmatic rocks within the Bajgan‐Durkan complex, although zircon U‐Pb ages show middle Jurassic ages (170–165 Ma) for the Bajgan‐Durkan magmatic rocks. Triassic zircons with εHf(t) values between −17 and +6.9 probably were supplied by the Bajgan‐Durkan complex and/or by Central Iran magmatic rocks. Paleozoic detrital zircons show major peaks at 330 (Carboniferous) and 460 Ma (Ordovician). Their εHf(t) values range from −51 to +18.2 and −9.5 to +4.6, respectively. Carboniferous detrital zircons may have come from the erosion of alkaline gabbros and A‐type granites reported from the NW, NE, SE, and central segments of the Sanandaj‐Sirjan zone and/or may have been supplied from reworking of Carboniferous strata of the Bajgan‐Durkan complex. Late Neoproterozoic‐Early Cambrian detrital zircons with εHf(t) values from −42.9 to +32.4 are suggested to be derived from the Cadomian magmatic rocks of Iran and Anatolia. The pre‐Cadomian detrital zircons with εHf(t) values of −28.9 to +27.5 are consistent with derivation from magmatic rocks of the Arabian‐Nubian Shield. Archean (2.5 Ga) and Paleoproterozoic (2.4–1.8 Ga) detrital zircons probably come from the Afro‐Arabian Craton and Saharan Metacraton. New data from detrital zircons imply that the MAC evolved from Triassic to Eocene and incorporated all orogenic elements including the continental lithosphere, oceanic crust, and its nearby continental arcs during its evolutionary cycle.
Legal Change and Water Market Transaction Costs in Colorado
Authors: Womble Philip , Hanemann W. Michael
Published: January 2020

Water markets are commonly described as failing to achieve efficient water management because of transaction cost barriers to trade. In the western United States, two sources of legal conflict frequently drive transaction costs: (1) negative externalities of trading and (2) uncertain property rights. Conflicts arise because water law applies a no‐injury rule that prevents water transfers from modifying water available to third‐party water rights and defines water rights by historical water use, among other reasons. Existing literature suggests many legal changes to reduce transaction costs, but no studies in the western United States quantify transaction costs under proposed future changes. Here we developed statistical models of transaction costs for water transfer proponents under four specific legal changes in the state of Colorado. Two legal changes would modify the no‐injury rule, and two aim to clarify property rights. Colorado hosts active markets and has recently experienced debate over such legal changes. By surveying 100 legal and hydrologic experts, we elicited transaction cost estimates and rankings of which legal changes were most likely to increase third‐party injury. The legal changes that aim to clarify property rights had significantly lower likelihoods of increasing injury. One of these legal changes, which would not limit transferable water to historical use in certain circumstances, also had the greatest reductions in proponents' transaction costs. Meanwhile, the legal changes that directly modify the no‐injury rule project substantial transaction cost savings but much higher likelihoods of increased injury. The results demonstrate trade‐offs between reducing transaction costs and increasing third‐party effects.
Combined Effects of Mean Flow and Turbulence on Sediment Pickup Rate
Authors: Cheng N. S. , Wei M. X. , Chiew Y. M. , Lu Y. S. , Emadzadeh A.
Published: January 2020

This paper aims to explore the combined main flow and turbulence influence on sediment pickup rates by investigating four purposely devised cases, namely, (1) unobstructed flow over a plane bed; (2) unobstructed flow over a rigid‐dune bed; (3) flow obstructed by a horizontal pipe; and (4) flow obstructed by a vertical pipe. The four cases were used to represent typical scenarios of mean flow combined with turbulence of varying intensities. By analyzing the dependence of sediment pickup rate on different combinations of the mean and turbulent flow parameters, a modified densimetric Froude number, incorporating both the bulk‐averaged velocity and maximum root‐mean‐square value of the fluctuating velocity, is found to be reasonably correlated with the measured pickup rates for all the four cases. Consequently, by relating the pickup rate with the dimensionless particle diameter and the modified densimetric Froude number, a generalized equation that predicts the pickup rates under both unobstructed as well as obstructed flow conditions is obtained.