bluuebunny/crossref_metadata_2025 huggingface dataset:
Tetranychusevansi spider mite populations suppress tomato defenses to varying degrees
Authors: Knegt Bram , Meijer Tomas T. , Kant Merijn R. , Kiers E. Toby , Egas Martijn
Published: April 2020

Plant defense suppression is an offensive strategy of herbivores, in which they manipulate plant physiological processes to increase their performance. Paradoxically, defense suppression does not always benefit the defense‐suppressing herbivores, because lowered plant defenses can also enhance the performance of competing herbivores and can expose herbivores to increased predation. Suppression of plant defense may therefore entail considerable ecological costs depending on the presence of competitors and natural enemies in a community. Hence, we hypothesize that the optimal magnitude of suppression differs among locations. To investigate this, we studied defense suppression across populations of Tetranychus evansi spider mites, a herbivore from South America that is an invasive pest of solanaceous plants including cultivated tomato, Solanum lycopersicum, in other parts of the world. We measured the level of expression of defense marker genes in tomato plants after infestation with mites from eleven different T. evansi populations. These populations were chosen across a range of native (South American) and non‐native (other continents) environments and from different host plant species. We found significant variation at three out of four defense marker genes, demonstrating that T. evansi populations suppress jasmonic acid‐ and salicylic acid‐dependent plant signaling pathways to varying degrees. While we found no indication that this variation in defense suppression was explained by differences in host plant species, invasive populations tended to suppress plant defense to a smaller extent than native populations. This may reflect either the genetic lineage of T. evansi—as all invasive populations we studied belong to one linage and both native populations to another—or the absence of specialized natural enemies in invasive T. evansi populations.
Plant evolution can mediate negative effects from honey bees on wild pollinators
Authors: Milner James R. D. , Bloom Elias H. , Crowder David W. , Northfield Tobin D.
Published: April 2020

Pollinators are introduced to agroecosystems to provide pollination services. Introductions of managed pollinators often promote ecosystem services, but it remains largely unknown whether they also affect evolutionary mutualisms between wild pollinators and plants.

Here, we developed a model to assess effects of managed honey bees on mutualisms between plants and wild pollinators. Our model tracked how interactions among wild pollinators and honey bees affected pollinator and plant populations.

We show that when managed honey bees have a competitive advantage over wild pollinators, or a greater carrying capacity, the honey bees displace the wild pollinator. This leads to reduced plant density because plants benefit less by visits from honey bees than wild pollinators that coevolved with the plants.

As wild pollinators are displaced, plants evolve by increasing investment in traits that are attractive for honey bees but not wild pollinators. This evolutionary switch promotes wild pollinator displacement. However, higher mutualism investment costs by the plant to the honey bee can promote pollinator coexistence.

Our results show plant evolution can promote displacement of wild pollinators by managed honey bees, while limited plant evolution may lead to pollinator coexistence. More broadly, effects of honey bees on wild pollinators in agroecosystems, and effects on ecosystem services, may depend on the capacity of plant populations to evolve.
Comparing sea ice habitat fragmentation metrics using integrated step selection analysis
Authors: Biddlecombe Brooke A. , Bayne Erin M. , Lunn Nicholas J. , McGeachy David , Derocher Andrew E.
Published: April 2020

Habitat fragmentation occurs when continuous habitat gets broken up as a result of ecosystem change. While commonly studied in terrestrial ecosystems, Arctic sea ice ecosystems also experience fragmentation, but are rarely studied in this context. Most fragmentation analyses are conducted using patch‐based metrics, which are potentially less suitable for sea ice that has gradual changes between sea ice cover, than distinct “long‐term” patches. Using an integrated step selection analysis, we compared the descriptive power of a patch‐based metric to a more novel metric, the variation in local spatial autocorrelation over time. We used satellite telemetry data from 39 adult female polar bears (Ursus maritimus) in Hudson Bay to examine their sea ice habitat using Advanced Microwave Scanning Radiometer 2 data during sea ice breakup in May through July from 2013–2018. Spatial autocorrelation resulted in better model fits across 64% of individuals, although both metrics were more effective in describing movement patterns than habitat selection. Variation in local spatial autocorrelation allows for the visualization of sea ice habitat at complex spatial and temporal scales, condensing a targeted time period of habitat that would otherwise have to be analyzed daily.
Green processing protocol for germinating and wet milling brown rice for beverage formulations: Sprouting, milling and gelatinization effects
Authors: Beaulieu John C. , Reed Shawndrika S. , Obando‐Ulloa Javier M. , McClung Anna M.
Published: April 2020

Rice‐derived beverages offer a non‐soy, lactose‐free, cholesterol and gluten‐free food source, which may offer well‐balanced nutrition. Brown rice is nutritionally superior to white rice but oil oxidation and rancidity can be problematic regarding organoleptics during processing and storage. Using green technologies, which do not rely upon stabilization, brown rice was sprouted and processed with enzymes to produce preliminary value‐added rice beverages. Paddy (rough) Rondo rice was dehulled using a pilot plant dehusker, sorted and cleaned into brown rice (BRR), rinsed, and germinated under various conditions (times and temperatures). Germinated brown rice (GBR) was then assessed (96.7 ± 0.8% germination and coleoptile length 2.24 ± 0.83 mm) prior to developing a method to soften, wet mill, sieve and gelatinize the matrix. Moderate macronutrient catabolism based on proximate analysis (e.g., 27.0%, 30.9% and 28.9% protein, oil and carbohydrate loss, respectively) and significantly decreased phytic acid (71.6%) from BRR → GBR along with processing efficiency were used to establish a germination and processing protocol engaging the natural enzymatic hydrolysis of starch and other biochemical changes. Based on rapid visco analyzer pasting properties in heated BRR, GBR sieving results and observations of stored crude beverages, proteins and oils apparently remained soluble and were conveyed forward into an the enzyme‐treated solubilized oligosaccharide matrix, which could be a natural emulsion. A method for germinating and processing brown rice, leading to a completely green process and “free‐flowing” soluble matrix to deliver preliminary sprouted brown rice beverages is presented.
Do older people know why they take benzodiazepines? A national French cross‐sectional survey of long‐term consumers
Authors: Laforgue Edouard‐Jules , Jobert Alexandra , Rousselet Morgane , Grall‐Bronnec Marie ,   FAN network, Jolliet Pascale , Feuillet Fanny , Victorri‐Vigneau Caroline
Published: April 2020

Objectives

Benzodiazepines and non‐benzodiazepine hypnotics (or Z‐drugs) (BZD/Z) are widely prescribed for older patients despite major side effects and risks when chronically used. The patient's understanding of the treatment is one of the keys to good adherence. The purpose of the study was to assess the knowledge of BZD/Z treatment among older people who were taking BZD/Z for the long term by studying the concordance between the declared reason for taking BZD/Z and its indication.

Methods

This was a cross‐sectional, pharmacoepidemiologic ancillary of a national study. Data were collected through a semi‐structured interview. All patients from the main study were included. “Good knowledge” was considered when patients gave an indication for each BZD/Z that was similar to its marketing authorisation. Univariate and multivariate analyses were carried out to adequately determine profiles and characterise associations.

Results

More than half of the patients (61.6%) had a good knowledge regarding their treatment. The presence of a psychiatric disorder, a mean duration of BZD/Z use of less than 120 months, a desire to stop treatment, educational status and number and type of BZD/Z used were significantly associated (P < .05) with good knowledge. In the multivariate analysis, only a psychiatric disorder, educational status and taking at least one hypnotic drug were associated with good knowledge.

Conclusions

At the time of shared medical decision, it appears essential to improve the knowledge of the treatment by the patient. The rate of patients with good knowledge of their BZD/Z treatment remains low and even lower than what was previously found in the literature for other drug classes. In contrast to patients with good knowledge, these data highlight the characteristics of patients with poor knowledge of their BZD/Z treatment, which may allow populations at risk to be targeted and enable education measures to be strengthened.
Intensive control of hypertension and risk of Alzheimer's dementia in older adults with depression
Authors: Yeung Anthony , Kiss Alex , Gallagher Damien
Published: April 2020

Objectives

Intensive control of hypertension has been reported to decrease risk of cognitive decline. However, the effect of this in older adults with hypertension and comorbid depression is not well understood. We aim to identify whether intensive control of systolic blood pressure (BP) is associated with reduced risk of Alzheimer's dementia (AD) in a clinical population.

Methods

Using data from the National Alzheimer's Coordinating Center, we conducted survival analyses in older adults with normal cognition at baseline and treated hypertension. We also examined those with comorbid depression, to determine if intensive control of systolic BP (≤120 mmHg) was associated with reduced risk of AD.

Results

In all older adults with treated hypertension (n = 4505), 298 (6.6%) developed AD during a median follow‐up duration of 4.2 years. In the comorbid depression subgroup (n = 1327), 152 (11.5%) developed AD. Intensive control of systolic BP was not significantly associated with reduced risk of AD in the overall sample (HR 1.13, 95%, 0.79‐1.64). However, in the comorbid depression subgroup, intensive control of systolic BP (≤120 mmHg) was associated with increased risk of AD (HR 1.49, 95%, 1.03‐2.15) compared to standard control (121‐139 mmHg).

Conclusions

In a clinical population of older adults with hypertension and comorbid depression, we found that an intensive systolic BP target of ≤120 mmHg was associated with increased risk of AD. While these findings are preliminary, they suggest that a more cautious approach to hypertension treatment may be warranted in this vulnerable subgroup.
Should Institutions Disclose the Names of Employees with Covid‐19?
Authors: Sulmasy Daniel P. , Veatch Robert M.
Published: April 2020

Prestigious University is a large, private educational institution with a medical school, a university hospital, a law school, and graduate and undergraduate colleges all on a single campus. In the face of the Covid‐19 pandemic, students were told during spring break to return to campus only briefly to retrieve their belongings. Classes then went online. On March 23, 2020, the faculty, students, and staff were emailed the following by the university's director of infection control and public health:

We have become aware that a Prestigious University staff member has tested positive for the virus that causes Covid‐19. The individual, who was last on campus on March 16, is now in isolation at their permanent residence and is doing well clinically. The university has already identified those members of our community who may have been in close contact with this individual, and we are working to notify them. Further, this individual's local health department has a protocol for identifying people who have been in direct contact with anyone testing positive for Covid‐19 (such as this Prestigious University staff member) so that they can self‐quarantine and watch for COVID‐19 symptoms for a period of 14 days from their last contact with the infected individual.

A professor in the Philosophy Department has asked the ethicists at the medical school whether such contact tracing suffices. “Don't the members of the community deserve to know who this is? Isn't there a mandate to identify this person in order to maximize public health benefits and slow the spread of this deadly virus?”
Does knowing translate to doing? Practitioners’ experiences of Circle of Security‐Parenting (COS‐P) training and implementation
Authors: Cooper Deena A. , Coyne Joe
Published: April 2020

This study sought to understand how practitioners perceive and experience the Circle of Security‐Parenting (COS‐P) training, and further, how they integrate and implement it into practice, and how these experiences influence their use and understanding of the program and its underlying model. A thematic analysis of semistructured interviews at two time points (shortly after training and 3–6 months after training) was used to explore 12 practitioners’ experiences of COS‐P training and subsequent implementation. Three main themes were identified; clinical salience, personal salience, and partial use of the program. The findings reflected participants’ common perception that the model is relevant and generalizable to a wide variety of contexts. It also highlighted potential barriers to implementation, particularly practitioners’ experiences using only components of the COS‐P program in isolation. The results suggest practitioners’ assumptions about client complexities, vulnerabilities, and/or incapacities, can prompt practitioners to withhold the use of COS‐P (in part or whole), thereby potentially neglecting key components required for client change. The only participants who implemented the COS‐P training in full had additional training in Circle of Security.
Implementation of a distance‐based clinical capstone course to improve practice‐related confidence and experiential readiness in global Pharm.D. candidates
Authors: Reynolds Paul M. , Rhein Erica J. , Saseen Joseph J. , Gleason Shaun E.
Published: April 2020

Introduction

Clinical capstone courses may improve skill sets across health care education. Effective implementation of a distance‐based clinical capstone course for practicing pharmacists across the globe has not been described.

Objectives

To evaluate whether a distance‐based clinical capstone course improves student confidence in key domains related to success on experiential rotations.

Methods

This was an educational cohort study with surveys at baseline, throughout the course, and after completion of advanced pharmacy practice experiences (APPEs). The distance‐based clinical capstone incorporated longitudinal case discussions, standardized patient interviews, drug information questions, increasingly complex case scenarios, and student‐driven learning. The primary outcome was the improvement in student confidence in critical thinking, evaluation and application of literature, clinical decision‐making, problem‐solving, and preparedness for APPEs. Student surveys (Likert scale) were conducted at baseline, midpoint, and course completion for the primary outcome. Key secondary outcomes included academic performance on student‐driven cases and performance compared with the face‐to‐face capstone course.

Results

Across 2 years, the course enrolled 46 students from 14 countries with a mean practice experience of 17 years. Compared with baseline, both midpoint and postcourse surveys revealed significant (P < .05) improvements in confidence regarding critical thinking, evaluation and application of literature, clinical decision‐making, problem‐solving, and preparedness for APPEs, which were maintained after completion of at least one APPE. Academic performance on student‐driven cases was not significantly different from faculty‐facilitated cases (88.6% vs 89.6%; P = .14) and overall performance was not significantly different between face‐to‐face and online iterations of the course (87% vs 88%; P = .52).

Conclusions

Implementation of a distance‐based clinical capstone course was effective in improving perceived student confidence in domains related to preparedness for experiential rotations and clinical practice.
Adsorption of three selected flavonoids with humic fraction‐modified silica gel in hexane: A mechanism study
Authors: Chen Shushi
Published: April 2020

Three selected flavonoids, commonly found in spices, red‐purple fruits, and vegetables, were adsorbed on humic fraction‐modified silica gel in hexane. The percentage of adsorption in hexane for all examined analytes was nearly 100% after 1 hr, as a result of the strong dipole–dipole interaction. The increasing amount of adsorbent involved in the process improved the percentage of adsorption, which in turn shortened the time needed to reach the maximum by providing more binding sites. However, adsorption was not observed in other liquid phases under the same conditions, such as acetonitrile and ethyl ether. The mechanism leading to the adsorption was explored chromatographically, as well as by fourier transform infrared spectroscopy (FTIR) and theoretical simulations.
Mistreatment from peers can reduce the effects of respectful treatment from bosses, and respectful peers can offset mistreatment from bosses
Authors: Bendersky Corinne , Brockner Joel
Published: April 2020

The present studies examine the joint influence of interpersonal fairness from peers and authorities on participants' organizational behaviors (citizenship) and attitudes (commitment). In three experimental studies, we find that mistreatment from peers, in the form of interpersonal unfairness, reduces the benefits that authorities gain from treating the same employee with high interpersonal fairness themselves. We also find that the negative effect of mistreatment from authorities can be offset by high interpersonal fairness from peers. These results come about because the interpersonal fairness shown not only by authorities but also by peers influences people's sense of standing as organization members. We discuss theoretical and practical implications, as well as limitations and suggestions, for future research.
How a Malnutrition Quality Improvement Initiative Furthers Malnutrition Measurement and Care: Results From a Hospital Learning Collaborative
Authors: Valladares Angel F. , Kilgore Karl M. , Partridge Jamie , Sulo Suela , Kerr Kirk W. , McCauley Sharon
Published: April 2020

Background

Malnutrition in hospitalized patients can adversely affect health outcomes and increase the cost of care. Real‐world strategies are needed for prompt identification and treatment of patients at risk of malnutrition.

Objectives

The aim of this quality improvement (QI) study was to measure the impact of a nutrition‐focused program on the malnutrition care processes of participating hospitals. Secondary objectives were to determine whether improvements in these nutrition‐related processes reduced hospital readmissions and length of stay (LOS) in patients ≥65 years.

Methods

A group of 27 US hospitals (“The Collaborative”) implemented the Malnutrition Quality Improvement Initiative (MQii), as guided by a Malnutrition QI Toolkit and 4 electronic clinical quality measures (eCQMs), including (1) nutrition screening; (2) nutrition assessment following detection of malnutrition risk; (3) nutrition care plan for patients identified as malnourished after completed nutrition assessment; and (4) documentation of malnutrition diagnoses. Multivariate analyses identified the variables best correlated with patient outcomes.

Results

Improvements were observed for all 4 eCQMs. The greatest improvements were achieved as a result of timely nutrition assessment (P = .06) and malnutrition diagnosis (P = .02). Patients ≥65 years with a malnutrition diagnosis and nutrition care plan had a 24% lower likelihood of 30‐day readmission but a longer mean LOS than did those without a care plan.

Conclusions

In this study, the implementation of MQii practices significantly improved the identification of malnutrition. The prompt identification and treatment of patients at malnutrition risk can improve patient care and health, as well as reduce costly readmissions.
Optimizing autologous bone contribution to implant osseointegration
Authors: Coyac Benjamin R. , Sun Qiang , Leahy Brian , Salvi Giuseppe , Yuan Xue , Brunski John B. , Helms Jill A.
Published: April 2020

Background

Autologous bone can be harvested from the flutes of a conventional drill or from a bone scraper; here we compared whether autologous bone chips generated by a new slow‐speed instrument were more osteogenic than the bone chips generated by conventional drills or bone scrapers. Additionally, we tested whether the osteogenic potential of bone chips could be further improved by exposure to a Wnt signaling (WNT) therapeutic.

Methods

Osteotomies were prepared in fresh rat maxillary first molar extraction sockets using a conventional drill or a new osseo‐shaping instrument; titanium alloy implants were placed immediately thereafter. Using molecular/cellular and histologic analyses, the fates of the resulting bone chips were analyzed. To test whether increasing WNT signaling improved osteogenesis in an immediate post‐extraction implant environment, a WNT therapeutic was introduced at the time of implant placement.

Results

Bone collected from a conventional drill exhibited extensive apoptosis; in contrast, bone generated by the new instrument remained in situ, which preserved their viability. Also preserved was the viability of the osteoprogenitor cells attached to the bone chips. Exogenous treatment with a WNT therapeutic increased the rate of osteogenesis around immediate post‐extraction implants.

Conclusions

Compared with conventional drills or bone scrapers, a new cutting instrument enabled concomitant site preparation with autologous bone chip collection. Histology/histomorphometric analyses revealed that the bone chips generated by this new tool were more osteogenic and could be further enhanced by exposure to a WNT therapeutic. Even though gaps still existed in placebo controls and liposomal WNT3A (L‐WNT3A) cases, the area of peri‐implant bone was significantly greater in L‐WNT3A treated sites.
Melatonin ameliorates periodontitis‐related inflammatory stress at cardiac left ventricular tissues in rats
Authors: Köse Oğuz , Kurt Bayrakdar Sevda , Akyıldız Kerimali , Altın Ahmet , Arabacı Taner , Yemenoglu Hatice , Zihni Korkmaz Meltem , Köse Taha Emre , Türker Sener Leyla , Mercantepe Tolga , Tümkaya Levent , Yılmaz Adnan
Published: April 2020

Background

The aim of this experimental rat study was to investigate the potential inflammatory effects of periodontitis on cardiac left ventricular tissue and the therapeutic activity of melatonin on these effects.

Methods

Twenty‐four male Sprague‐Dawley rats were randomly divided into three groups: control, experimental periodontitis (Ep), and Ep‐melatonin (Ep‐Mel). Experimental periodontitis was induced by placing and maintaining 3.0 silk ligatures at a peri marginal position on the left and right mandibular first molars for 5 weeks. Afterward, following the removal of ligatures, melatonin (10 mg/body weight) to Ep‐Mel group, and vehicle (saline) to Ep and control groups were administered intraperitoneally for 14 days. On the first day of the eighth week, mandibular and cardiac left ventricular tissue samples were obtained following the euthanasia of the rats in all groups. Alveolar bone loss measurements were made on histological and microcomputed tomographic slices. Cardiac tissue levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), matrix metalloproteinase‐9 (MMP‐9), and cardiac Troponin‐T (cTnT) were evaluated by appropriate biochemical methods.

Results

Measurements made on the histological and microcomputed tomographic slices showed that melatonin significantly limits the ligature‐induced periodontal tissue destruction (P <0.01). In addition, melatonin was detected to cause a significant decrease of MDA, MMP‐9, and cTnT levels which were found to be significantly higher on rats with Ep (P <0.05) while having no significant effect on antioxidant levels (GSH, SOD, and CAT) (P >0.05).

Conclusion

Melatonin might be regarded as an important supportive therapeutic agent to reduce the early degenerative changes and possible hypertrophic remodeling at cardiac left ventricular tissues provoked by periodontitis‐related bacteria and/or periodontal inflammation.
High‐efficiency quantum dot light‐emitting diodes with blue cadmium‐free quantum dots
Authors: Ryowa Tatsuya , Ishida Takeshi , Sakakibara Yusuke , Kitano Keisuke , Ueda Masaya , Izumi Makoto , Ogura Yuko , Tanaka Masanori , Nikata Soichiro , Watanabe Mayuko , Takasaki Mikihiro , Itoh Tetsuji , Miyanaga Akiharu
Published: April 2020

We report outstanding electroluminescence properties of high‐efficiency blue cadmium‐free quantum dot light‐emitting diodes (QD‐LED). External quantum efficiency (EQE) of 14.7% was achieved for QD‐LED emitting at 428 nm. Furthermore, we developed high‐efficiency and narrow wavelength emission zinc selenide (ZnSe) nanocrystals emitting at 445 nm and achieved QD‐LED with an EQE of 10.7%. These new QDs have great potential to be used in next‐generation QD‐LED display with wide color gamut.
Method development and validation for the determination of biogenic amines in soy sauce using supercritical fluid chromatography coupled with single quadrupole mass spectrometry
Authors: Song Liu , Huang Yang , Gou Marie‐Jia , Crommen Jacques , Jiang Zhengjin , Feng Yifan
Published: April 2020

Biogenic amines have been reported in many foods such as fish, meat, and soy sauce. The consumption of foods containing high concentrations of biogenic amines has been associated with health hazards. In this study, a green and efficient method using supercritical fluid chromatography coupled with single quadrupole mass spectrometry was developed for determination of biogenic amines in soy sauce. The chromatographic and mass spectrometry conditions were systematically optimized in terms of selectivity and peak shape. Nine biogenic amines were well separated within 25 min on a Cosmosil 5HP column using 5% (v/v) water and 0.2% (v/v) ammonia solution in methanol as mobile phase additives at a backpressure of 120 bar and temperature of 40°C. The established method was fully validated regarding the linearity, sensitivity, precision, and accuracy. The limits of detection and limits of quantification ranged from 0.03 to 10.50 μg/mL and 0.10 to 23.1 μg/mL, respectively. The relative standard deviations for intra‐ and interday precisions were all lower than 9.36% and the recoveries ranged from 75.82 to 99.63% and 80.10 to 99.89% for two levels of standards spiked in soy sauce, respectively. Finally, the established method was successfully applied to the quantitative analysis of biogenic amines in soy sauce.
A Systematic Review of Picosecond Laser in Dermatology: Evidence and Recommendations
Authors: Wu Douglas C. , Goldman Mitchel P. , Wat Heidi , Chan Henry H.L.
Published: April 2020

Background and Objectives

The use of picosecond laser in dermatology was originally focused on optimizing the removal of unwanted tattoos. Subsequent advances in this technology have broadened its clinical indications to include treatment of benign pigmented lesions, photodamage, melasma, and scar revision. In this systematic review, evidence‐based recommendations are developed for the use of picosecond laser in dermatology.

Study Design/Materials and Methods

A comprehensive search of the English language literature was performed up to and including November 2019. Relevant citations were individually evaluated, synthesized, and categorized based on the Level of Evidence. With the addition of the authors’ combined clinical experience, clinical recommendations were developed.

Results

After application of inclusion and exclusion criteria, a total of 77 unique studies were evaluated. Treatment of benign pigmented lesions was associated with level I–IV evidence; rejuvenation was associated with level II evidence; melasma was associated with level II evidence; scar revision was associated with level II–III evidence; tattoo removal was associated with level I evidence.

Conclusion

Picosecond laser is a safe and effective treatment modality for an increasing range of dermatologic indications. Further development of this technology is warranted. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.
Location decisions and welfare under spatial price discrimination
Authors: Eleftheriou Konstantinos , Michelacakis Nickolas J.
Published: April 2020

The welfare effects of regulation are of crucial importance to policy makers. To this end, we present a model of n firms with differentiated costs competing in a linear market within the framework of spatial price discrimination. We prove that the Nash equilibrium locations of firms are always socially optimal irrespective of the number of competitors, the distribution of consumers, firms' cost heterogeneity, the level of privatization, and the number and/or the varieties of the produced goods. We also provide an algorithm on how to find the unique Nash equilibrium in the case of uniformly distributed consumers.
Asymptotic analysis of an elastic rod with rounded ends
Authors: Nazarov Sergey A. , Slutskij Andrey S. , Taskinen Jari
Published: April 2020

We derive a one‐dimensional model for an elastic shuttle, that is, a thin rod with rounded ends and small fixed terminals, by means of an asymptotic procedure of dimension reduction. In the model, deformation of the shuttle is described by a system of ordinary differential equations with variable degenerating coefficients, and the number of the required boundary conditions at the end points of the one‐dimensional image of the rod depends on the roundness exponent m∈(0,1). Error estimates are obtained in the case m∈(0,1/4) by using an anisotropic weighted Korn inequality, which was derived in an earlier paper by the authors. We also briefly discuss boundary layer effects, which can be neglected in the case m∈(0,1/4) but play a crucial role in the formulation of the limit problem for m ≥ 1/4.
Sustainable vector/pest control using the permanent sterile insect technique
Authors: Anguelov Roumen , Dumont Yves , Yatat Djeumen Ivric Valaire
Published: April 2020

Vector/pest control is essential to reduce the risk of vector‐borne diseases or losses in crops. Among all biological control tools, the sterile insect technique (SIT), which consists of massive releases of sterile insects to reach elimination or to lower a vector/pest population under a certain threshold, is the most promising one. The models presented here are minimalistic with respect to the number of parameters and variables. The first model deals with the dynamics of the vector population, while the second model tackles the interaction between treated males and wild female vectors. For the vector population model, equilibrium 0 is globally asymptotically stable when the basic offspring number,
, whereas 0 becomes unstable and one stable positive equilibrium exists, with well‐determined basins of attraction, when
. For the SIT model, we obtain a threshold number of treated males above which the control of wild population is effective using massive releases. When the amount of treated males is lower than the aforementioned threshold, the SIT model experiences a strong Allee effect, that is, 0 becomes locally asymptotically stable, while a positive equilibrium still exists. Practically, massive releases of sterile males are only possible for a short period. That is why using the Allee effect, we develop a new strategy to maintain the wild population under a certain threshold, for a permanent and sustainable low level of SIT control. We illustrate our theoretical results with numerical simulations. In particular, we study the combination of SIT with other control tools, like mechanical control and adulticide.
On strong solutions for a class of semilinear fractional degenerate evolution equations with lower fractional derivatives
Authors: Plekhanova Marina V. , Baybulatova Guzel D.
Published: April 2020

The existence of a unique strong solution on a given interval is proved for the generalized Showalter–Sidorov problem to a class of semilinear fractional degenerate evolution equations in Banach spaces. Nonlinearity is assumed to be dependent on lower order fractional derivatives. All fractional derivatives are understood in the sense of Gerasimov–Caputo. The obtained abstract result is applied to study an initial‐boundary value problem to a modified Sobolev system of equations of the motion of rotated stratified fluid, which is perturbed by a nonlinearity depending on a lower fractional derivative, and a class of initial‐boundary value problems to the semilinear time‐fractional equation with polynomials of an elliptic self‐adjoint differential with respect to spatial variables operator as linear operators in the considered above abstract equation.
A modified perturbation method for mathematical models with randomness: An analysis through the steady‐state solution to Burgers' partial differential equation
Authors: Calatayud Julia , Cortés Juan Carlos , Jornet Marc
Published: April 2020

The variability of the data and the incomplete knowledge of the true physics require the incorporation of randomness into the formulation of mathematical models. In this setting, the deterministic numerical methods cannot capture the propagation of the uncertainty from the inputs to the model output. For some problems, such as the Burgers' equation (simplification to understand properties of the Navier–Stokes equations), a small variation in the parameters causes nonnegligible changes in the output. Thus, suitable techniques for uncertainty quantification must be used. The generalized polynomial chaos (gPC) method has been successfully applied to compute the location of the transition layer of the steady‐state solution, when a small uncertainty is incorporated into the boundary. On the contrary, the classical perturbation method does not give reliable results, due to the uncertainty magnitude of the output. We propose a modification of the perturbation method that converges and is comparable with the gPC approach in terms of efficiency and rate of convergence. The method is even applicable when the input random parameters are dependent random variables.
MR‐based PET attenuation correction using a combined ultrashort echo time/multi‐echo Dixon acquisition
Authors: Han Paul Kyu , Horng Debra E. , Gong Kuang , Petibon Yoann , Kim Kyungsang , Li Quanzheng , Johnson Keith A. , El Fakhri Georges , Ouyang Jinsong , Ma Chao
Published: April 2020

Purpose

To develop a magnetic resonance (MR)‐based method for estimation of continuous linear attenuation coefficients (LACs) in positron emission tomography (PET) using a physical compartmental model and ultrashort echo time (UTE)/multi‐echo Dixon (mUTE) acquisitions.

Methods

We propose a three‐dimensional (3D) mUTE sequence to acquire signals from water, fat, and short T2 components (e.g., bones) simultaneously in a single acquisition. The proposed mUTE sequence integrates 3D UTE with multi‐echo Dixon acquisitions and uses sparse radial trajectories to accelerate imaging speed. Errors in the radial k‐space trajectories are measured using a special k‐space trajectory mapping sequence and corrected for image reconstruction. A physical compartmental model is used to fit the measured multi‐echo MR signals to obtain fractions of water, fat, and bone components for each voxel, which are then used to estimate the continuous LAC map for PET attenuation correction.

Results

The performance of the proposed method was evaluated via phantom and in vivo human studies, using LACs from computed tomography (CT) as reference. Compared to Dixon‐ and atlas‐based MRAC methods, the proposed method yielded PET images with higher correlation and similarity in relation to the reference. The relative absolute errors of PET activity values reconstructed by the proposed method were below 5% in all of the four lobes (frontal, temporal, parietal, and occipital), cerebellum, whole white matter, and gray matter regions across all subjects (n = 6).

Conclusions

The proposed mUTE method can generate subject‐specific, continuous LAC map for PET attenuation correction in PET/MR.
Dynamics of exchange rate and stock price volatility: Evidence from India
Authors: Vadivel Arjunan
Published: April 2020

The article examines causal relationship between exchange rate and stock price volatility. We use daily data from February 2, 2015 to August 30, 2019 to estimate variables employed in ARCH/GARCH, and cross correlation. It gives a feedback that effect between the conditional mean and variance of exchange rate and stock price volatility. The stock market has brought more capital inflow rupee that appreciate while capital moves out of the monetary system rupee depreciate. The Reserve Bank of India has a policy to encourage and to bring huge inflows instead of outflows.
Synthesis of sugar‐based macromolecules via sono‐ATRP in miniemulsion
Authors: Zaborniak Izabela , Surmacz Karolina , Chmielarz Paweł
Published: April 2020

Ultrasound‐mediated atom transfer radical polymerization (sono‐ATRP) in miniemulsion media is used for the first time for the preparation of complex macromolecular architectures by a facile two‐step synthetic route. Initially, esterification reaction of sucrose or lactulose with α‐bromoisobutyryl bromide (BriBBr) is conducted to receive multifunctional ATRP macroinitiators with 8 initiation sites, followed by polymerization of n‐butyl acrylate (BA) forming arms of the star‐like polymers. The brominated lactulose‐based molecule was examined as an ATRP initiator by determining the activation rate constant (ka) of the catalytic process in the presence of a copper(II) bromide/tris(2‐pyridylmethyl)amine (CuIIBr2/TPMA) catalyst in both organic solvent and for the first time in miniemulsion media, resulting in ka = (1.03 ± 0.01) × 104 M−1 s−1 and ka = (1.16 ± 0.56) × 103 M−1 s−1, respectively. Star‐like macromolecules with a sucrose or lactulose core and poly(n‐butyl acrylate) (PBA) arms were successfully received using different catalyst concentration. Linear kinetics and a well‐defined structure of synthesized polymers reflected by narrow molecular weight distribution (Mw/Mn = 1.46) indicated 105 ppm wt of catalyst loading as concentration to maintain controlled manner of polymerization process. 1H NMR analysis confirms the formation of new sugar‐inspired star‐shaped polymers.
Monochorionic diamniotic twins: What do I tell the prospective parents?
Authors: Lewi Liesbeth
Published: April 2020

Monochorionic diamniotic twins occur in about 1 in 300 pregnancies. Compared with dichorionic twins, they face increased risks because of the shared circulation. In about 15%, an imbalance in blood exchange occurs, such as twin‐twin transfusion syndrome and twin anemia polycythemia sequence. In this review, we summarize the latest evidence on the management of monochorionic diamniotic twin pregnancies and their specific complications, with a focus on information that is relevant for prospective parents.
The construction and application of an ultrasound and anatomical cross‐sectional database of structural malformations of the fetal heart
Authors: Yang Zhen‐Juan , DeVore Greggory R. , Pei Qiu‐Yan , Yan Ya‐Ni , Li Yun‐Tao , Wang Yan
Published: April 2020

Objectives

Establish a fetal heart anatomical cross‐sectional database that correlates with screening transverse ultrasound images suggested by international professional organizations to detect congenital heart defects.

Methods

Fetuses with suspected congenital heart defects identified using the following cardiac image sequences obtained from transverse slices beginning from the upper abdomen and ending in the upper thorax were the subjects of this study: (1) four‐chamber view, (2) left ventricular outflow tract view, (3) three‐vessel right ventricular outflow tract view, and (4) the three‐vessel tracheal view. A database of digital two‐dimensional images of the transverse sweep was created for fetuses with confirmed congenital heart defects. In addition, using four‐dimensional ultrasound spatial‐temporal image correlation, selected transverse ultrasound images were acquired as part of the database. Ultrasound‐detected congenital heart defects were confirmed postnatally from pathological specimens of the heart and lungs using a cross‐sectional technique that mirrored the ultrasound images described above. When anatomical specimens were not available, prenatal ultrasound‐detected congenital heart defects were confirmed using postnatal echocardiography and/or following surgery.

Results

The four screening views described in the Methods section identified 160 fetuses that comprised the database. Forty‐five datasets consisted of both ultrasound and anatomical cross‐sectional images. Thirteen percent (6/45) only had abnormalities of the four‐chamber view (eg, endocardial cushion defects). Twenty‐four percent (11/45) had abnormalities of the four‐chamber view as well as right and left outflow tracts (eg, complex malformations). Of these, 10 of 11 had an abnormal tracheal view. Sixteen percent (7/45) had an abnormal four‐chamber view and abnormal right outflow tract (eg, pulmonary stenosis). Thirty‐three percent (15/45) had a normal four‐chamber view but had abnormal right and left outflow tracts as well as an abnormal tracheal view (eg, tetralogy of Fallot, D‐transposition of the great arteries).

Conclusions

Combining both ultrasound and anatomical imaging may be of assistance in training imagers to recognize cardiovascular pathology when performing the screening examination of the fetal heart.
Validity of administrative claims‐based algorithms for ventricular arrhythmia and cardiac arrest in the pediatric population
Authors: Czaja Angela S. , Collins Kathryn , Valuck Robert J. , Anderson Heather D. , Ghosh Debashis , Davidson Jesse A.
Published: April 2020

Purpose

Identify administrative claims‐based algorithms for capturing out‐of‐hospital ventricular arrhythmias (VA) and cardiac arrests (CA) due to cardiac causes in the pediatric population with high positive‐predictive value (PPV).

Methods

Within a single pediatric center, a retrospective cohort of patients hospitalized or seen in the emergency room for VA or CA were identified from the electronic health records. Eligible encounters were blindly reviewed and linked to administrative data, including ICD‐9/ICD‐10 codes. Test characteristics, including PPV, for different diagnostic and procedure codes were generated using a 50% training sample. The gold standard was definite or suspected out‐of‐hospital VA or CA due to cardiac cause verified based on clinical criteria. Algorithms with the highest PPV were then applied to a 50% validation sample to validate performance.

Results

From 2004‐2017, 598 encounters met eligibility criteria. 174 (29%) had an outcome of interest, with remainder being an inpatient event or CA due to other cause. Within the training sample (n = 263), VA codes in primary position had a PPV 94% (95%CI 81%‐99%) with low sensitivity (44%, 95%CI 33%‐56%). CA codes in any position or VA codes in nonprimary positions had low PPV (18%‐19%, 31% respectively). Applying the top three performing algorithms to the validation sample (n = 252) yielded similar PPV values.

Conclusions

Contrary to adults, algorithms including a CA code do not perform well for identifying out‐of‐hospital VA and CA due to cardiac cause in the pediatric populations. Researchers should be aware of the potential implications for future pediatric drug safety studies for these outcomes.
The Association of Parity with Greater Dynamic Pronation of the Feet
Authors: Heronemus Marc J. , Rabe Kaitlin , Tolstykh Irina , Gross K. Douglas , Wise Barton L , Nevitt Michael C. , Lewis Cora E. , Hillstrom Howard J. , Segal Neil A. ,   for the MOST Study Group
Published: April 2020

Background

Postpartum women are at increased risk for lower limb musculoskeletal disorders. Foot arch collapse following pregnancy has been reported as a mechanism for this increased risk. However, dynamic changes during gait in postpartum women have not been reported. Therefore, we assessed the association between parity and dynamic foot pronation during gait.

Objective

To determine (1) if there is an association between parity and dynamic foot pronation (center of pressure excursion index, CPEI) during gait; and (2) the extent to which there is a dose‐effect of parity on foot pronation.

Design

The Multicenter Osteoarthritis Study (MOST) Study is a longitudinal cohort study of adults with or at risk for knee osteoarthritis (OA).

Setting

Two communities in the United States, Birmingham, Alabama and Iowa City, Iowa.

Interventions

Not applicable

Participants

A population‐based sample of 1177 MOST participants who were female, had complete CPEI and parity data and completed the baseline, 30‐ and 60‐month visits.

Main Outcome Measures

Odds of a one quintile decrease in CPEI by parity group and mean CPEI by parity group.

Results

In 1177 women, mean age was 67.7 years and mean body mass index (BMI) was 30.6 kg/m2. As parity increased, there was significantly greater foot pronation, lower mean CPEI: 19.1 (18.2‐20.1), 18.9 (18.4‐19.4), 18 (17.5‐18.6) to 17.5 (16.4‐18.6) in the 0 to 4 and >5 children groups, respectively; (P = .002), which remained significant after adjusting for race and clinic site (P = .005). There was a positive linear trend (β = 1.08, 1.03‐1.14) in odds ratios of a one quintile decrease in CPEI (greater pronation) with increasing parity level (P = .004), which remained significant after adjusting for race and clinic site (P = .01). After adjusting for age and BMI, these two associations were no longer statistically significant.

Conclusions

This study indicates a positive correlation between parity and greater dynamic pronation of the feet.
The potential distribution and dynamics of important vectors Culex pipiens pallens and Culex pipiens quinquefasciatus in China under climate change scenarios: an ecological niche modelling approach
Authors: Liu Boyang , Gao Xiang , Zheng Keren , Ma Jun , Jiao Zhihui , Xiao Jianhua , Wang Hongbin
Published: April 2020

BACKGROUND

Intense studies have been carried out on the effects of climate change on vector‐borne diseases and vectors. Culex pipiens pallens and Culex pipiens quinquefasciatus are two medically concerned mosquito species in temperate and tropical areas, which serve as important disease‐transmitting pests of a variety of diseases. The ongoing geographical expansion of these mosquitoes has brought an increasing threat to public health.

RESULTS

Based on mosquito occurrence records and high‐resolution environmental layers, an ecological niche model was established to model their current and future potential distribution in China. Our model showed that the current suitable area for Cx. p. pallens is distributed in the central, eastern and northern parts of China, while Cx. p. quinquefasciatus is distributed in vast areas in southern China. Under future climate change scenarios, both species are predicted to expand their range to varying degrees and RCP 8.5 provides the largest expansion. Northward core shifts will occur in ranges of both species. Environmental variables which have significant impact on the distribution of mosquitoes were also revealed by our model.

CONCLUSION

Severe habitat expansion of vectors is likely to occur in the future 21st century. Our models mapped the high‐risk areas and risk factors which needs to be paid attention. The results of our study can be referenced in further ecological surveys and will guide the development of strategies for the prevention and control of vector‐borne diseases. © 2020 Society of Chemical Industry