bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Schwarz methods for a hybridizable discontinuous Galerkin discretization: The many-subdomain case
Authors: Gander Martin , Hajian Soheil
Published: May 2017

Schwarz methods are attractive parallel solution techniques for solving large-scale linear systems obtained from discretizations of partial differential equations (PDEs). Due to the iterative nature of Schwarz methods, convergence rates are an important criterion to quantify their performance. Optimized Schwarz methods (OSM) form a class of Schwarz methods that are designed to achieve faster convergence rates by employing optimized transmission conditions between subdomains. It has been shown recently that for a two-subdomain case, OSM is a natural solver for hybridizable discontinuous Galerkin (HDG) discretizations of elliptic PDEs. In this paper, we generalize the preceding result to the many-subdomain case and obtain sharp convergence rates with respect to the mesh size and polynomial degree, the subdomain diameter, and the zeroth-order term of the underlying PDE, which allows us for the first time to give precise convergence estimates for OSM used to solve parabolic problems by implicit time stepping. We illustrate our theoretical results with numerical experiments.
Invariance principle and rigidity of high entropy measures
Authors: Tahzibi Ali , Yang Jiagang
Published: May 2017

A deep analysis of the Lyapunov exponents for stationary sequence of matrices going back to Furstenberg, for more general linear cocycles by Ledrappier, and generalized to the context of non-linear cocycles by Avila and Viana, gives an invariance principle for invariant measures with vanishing central exponents. In this paper, we give a new criterium formulated in terms of entropy for the invariance principle and, in particular, obtain a simpler proof for some of the known invariance principle results.

As a byproduct, we study ergodic measures of partially hyperbolic diffeomorphisms whose center foliation is one-dimensional and forms a circle bundle. We show that for any such

C
2

C^2

diffeomorphism which is accessible, weak hyperbolicity of ergodic measures of high entropy implies that the system itself is of rotation type.
A gap theorem for the complex geometry of convex domains
Authors: Zimmer Andrew
Published: May 2017

In this paper we establish a gap theorem for the complex geometry of smoothly bounded convex domains which informally says that if the complex geometry near the boundary is close to the complex geometry of the unit ball, then the domain must be strongly pseudoconvex.

One consequence of our general result is the following: for any dimension there exists some

ϵ
>
0

\epsilon > 0

so that if the squeezing function on a smoothly bounded convex domain is greater than

1
−
ϵ

1-\epsilon

outside a compact set, then the domain is strongly pseudoconvex (and hence the squeezing function limits to one on the boundary). Another consequence is the following: for any dimension

d
d

there exists some

ϵ
>
0

\epsilon > 0

so that if the holomorphic sectional curvature of the Bergman metric on a smoothly bounded convex domain is within

ϵ
\epsilon

of

−
4

/

(
d
+
1
)

-4/(d+1)

outside a compact set, then the domain is strongly pseudoconvex (and hence the holomorphic sectional curvature limits to

−
4

/

(
d
+
1
)

-4/(d+1)

on the boundary).
Viscous displacement in porous media: the Muskat problem in 2D
Authors: Matioc Bogdan–Vasile
Published: May 2017

We consider the Muskat problem describing the viscous displacement in a two-phase fluid system located in an unbounded two-dimensional porous medium or Hele-Shaw cell. After formulating the mathematical model as an evolution problem for the sharp interface between the fluids, we show that the Muskat problem with surface tension is a quasilinear parabolic problem, whereas, in the absence of surface tension effects, the Rayleigh–Taylor condition identifies a domain of parabolicity for the fully nonlinear problem. Based upon these aspects, we then establish the local well-posedness for arbitrary large initial data in

H
s

H^s

,

s
>
2

s>2

, if surface tension is taken into account, respectively for arbitrary large initial data in

H
2

H^2

that additionally satisfy the Rayleigh–Taylor condition if surface tension effects are neglected. We also show that the problem exhibits the parabolic smoothing effect and we provide criteria for the global existence of solutions.
Labeling Food Processes: The Good, the Bad and the Ugly
Authors: Messer Kent D. , Costanigro Marco , Kaiser Harry M.
Published: May 2017

Consumers are increasingly exposed to labels communicating specific processing aspects of food production, and recent state and federal legislation in the United States has called for making some of these labels mandatory. This article reviews the literature in this area and identifies the positive and negative aspects of labeling food processes. The good parts are that, under appropriate third‐party or governmental oversight, process labels can effectively bridge the informational gap between producers and consumers, satisfy consumer demand for broader and more stringent quality assurance criteria, and ultimately create value for both consumers and producers. Despite the appeal of the “Consumer Right to Know” slogan, process labeling also can have serious unintentional consequences. The bad parts are that consumers can misinterpret these labels and thus misalign their personal preferences and their actual food purchases. The ugly parts are that these labels can stigmatize food produced with conventional processes even when there is no scientific evidence that they cause harm, or even that it is compositionally any different. Based on this review of the literature, we provide three policy recommendations: (i) mandatory labeling of food processes should occur only in situations in which the product has been scientifically demonstrated to harm human health; (ii) governments should not impose bans on process labels because this approach goes against the general desire of consumers to know about and have control over the food they are eating, and it can undermine consumer trust of the agricultural sector; and (iii) a prudent policy approach is to encourage voluntary process labeling, perhaps using smart phone technology similar to that proposed in 2016 federal legislation related to foods containing ingredients that were genetically engineered.
Disraeli, the East and Religion: Tancred in Context
Authors: Parry J P
Published: May 2017

Recently there has been much interest in Benjamin Disraeli’s writings, and particularly the importance to him of empire, race and Jewishness. His favourite among his own novels, Tancred (1847), set in the Near East, is now often said to advocate Asian imperialism and Jewish superiority and to mark a key stage in his ‘self-fashioning’ as a political leader. This article suggests that the problem with these interpretations, and with the older argument that Disraeli revelled in a lack of principle (which also draws on Tancred) is that they fail to put novel and author in the context of the time. By the 1840s, Disraeli’s books were not obsessed with his own identity; instead he used them to engage with important live issues. The Near Eastern themes which Tancred tackled included serious international questions and equally intense arguments about domestic Christianity, which were themselves heavily influenced by new perspectives on the East. The book discussed how the Church of England, weakened by sectarianism and materialism, could regain the leadership of national opinion. It attacked the liberal sectarian policy pursued by the Peel government in Syria and Lebanon, and European political, religious and economic intervention in the Ottoman Empire more broadly. Commentators have misunderstood what Disraeli meant by ‘empire’, and his (critical) remarks on modern Jews. They continue to present him as exotic, and have read Tancred accordingly, as a personal manifesto for unusual and one-sided causes. Once placed in the context of the time in which it was written, the book’s great theme is revealed as the opposite: the need to abandon partisanship for synthesis in Western and Eastern politics and religion, if a chaotic world is to be brought to order.
Disentangling the role of sea lice on the marine survival of Atlantic salmon
Authors: Vollset Knut Wiik , Dohoo Ian , Karlsen Ørjan , Halttunen Elina , Kvamme Bjørn Olav , Finstad Bengt , Wennevik Vidar , Diserud Ola H , Bateman Andrew , Friedland Kevin D , Mahlum Shad , Jørgensen Christian , Qviller Lars , Krkošek Martin , Åtland Åse , Barlaup Bjørn Torgeir
Published: May 2017

The effects of sea lice on the marine survival of wild salmonids are widely debated. In Norway this debate has reached a crescendo as the Norwegian government has recently ratified a management system where the growth in the salmonid aquaculture industry will be conditional on regional estimated impact of salmon lice on wild fish. Sea lice have thus become the most prominent obstacle to the stated political aim of quintupling aquaculture production in Norway by 2050. Scientific documentation that salmon lice impact the marine survival of salmon is robust. However, it is also evident that marine survival of salmon is strongly impacted by other factors, and that the effect of salmon lice is most likely an integral part of these other mortality factors. In this paper, our goal is to discuss and give advice on how managers and policy makers should handle this complexity, and to identify the greatest challenges in using scientific results to construct robust management rules. Inadequate extrapolation from the scale of known effects to the scale of management implementation may initially give a false impression of scientific certainty, but will eventually fuel upsetting disagreements among stakeholders as they gradually uncover the shaky foundation of the implemented policy. Thus, using a single model and parameter to determine management advice is not warranted, as no single data point reflects the natural complexity of nature. Furthermore, robust management rules should be based on unambiguous definitions of key concepts. Finally, despite the scientific consensus that salmon lice are a risk to salmon, studies on wild populations in situ that accurately quantify the impact of salmon lice are still urgently needed. We give advice on how this can be accomplished.
Stereotactic Radiosurgery for Brainstem Arteriovenous Malformations: A Multicenter Study
Authors: Cohen-Inbar Or , Starke Robert M , Lee Cheng-Chia , Kano Hideyuki , Huang Paul , Kondziolka Douglas , Grills Inga S , Silva Danilo , Abbassy Mohmoud , Missios Symeon , Barnett Gene H , Lunsford L Dade , Sheehan Jason P
Published: May 2017

BACKGROUND

The management of brainstem arteriovenous malformations (bAVMs) is a formidable challenge. bAVMs harbor higher morbidity and mortality compared to other locations.

OBJECTIVE

To review the outcomes following stereotactic radiosurgery (SRS) of bAVMs in a multicenter study.

METHODS

Six medical centers contributed data from 205 patients through the International Gamma Knife Research Foundation. Median age was 32 yr (6-81). Median nidus volume was 1.4 mL (0.1-69 mL). Favorable outcome (FO) was defined as AVM obliteration and no post-treatment hemorrhage or permanent symptomatic radiation-induced complications.

RESULTS

Overall obliteration was reported in 65.4% (n = 134) at a mean follow-up of 69 mo. Obliteration was angiographically proven in 53.2% (n = 109) and on MRA in 12.2% (n = 25). Actuarial rate of obliteration at 2, 3, 5, 7, and 10 yr after SRS was 24.5%, 43.3%, 62.3%, 73%, and 81.8% respectively. Patients treated with a margin dose >20 Gy were more likely to achieve obliteration (P = .001). Obliteration occurred earlier in patients who received a higher prescribed margin dose (P = .05) and maximum dose (P = .041). Post-SRS hemorrhage occurred in 8.8% (n = 18). Annual postgamma knife latency period hemorrhage was 1.5%. Radiation-induced complications were radiologically evident in 35.6% (n = 73), symptomatic in 14.6% (n = 30), and permanent in 14.6% (n = 30, which included long-tract signs and new cranial nerve deficits). FO was achieved in 64.4% (n = 132). Predictors of an FO were a higher Virginia radiosurgery AVM scale score (P = .003), prior hemorrhage (P = .045), and a lower prescribed maximum dose (P = .006).

CONCLUSION

SRS for bAVMs results in obliteration and avoids permanent complications in the majority of patients.
Contrast Time-Density Time on Digital Subtraction Angiography Correlates With Cerebral Arteriovenous Malformation Flow Measured by Quantitative Magnetic Resonance Angiography, Angioarchitecture, and Hemorrhage
Authors: Brunozzi Denise , Hussein Ahmed E , Shakur Sophia F , Linninger Andreas , Hsu Chih-Yang , Charbel Fady T , Alaraj Ali
Published: May 2017

BACKGROUND

Digital subtraction angiography (DSA) currently provides angioarchitectural features of cerebral arteriovenous malformations (AVMs) but its role in the hemodynamic evaluation of AVMs is poorly understood.

OBJECTIVE

To assess contrast time-density time (TT) on DSA relative to AVM flow measured using quantitative magnetic resonance angiography (QMRA).

METHODS

Patients seen at our institution between 2007 and 2014 with a supratentorial AVM and DSA and QMRA obtained prior to any treatment were retrospectively reviewed. Regions of interest were selected on the draining veins at the point closest to the nidus. TT on DSA was defined as time needed for contrast to change image intensity from 10% to 100%, 100% to 10%, and 25% to 25%. TT was correlated to AVM total flow, angioarchitectural features, and hemorrhage.

RESULTS

Twenty-eight patients (mean age 35.6 yr) were included. Six patients presented with hemorrhage. Mean AVM volume was 11.42 mL (range 0.3-57.7 mL). Higher total AVM flow significantly correlated with shorter TT100%-10% and TT25%-25% (P = .02, .02, respectively). Presence of venous stenosis correlated significantly with shorter TT100%-10% (P = .04) and TT25%-25% (P = .04). AVMs with a single draining vein exhibited longer TT25%-25% compared to those with multiple draining veins (P = .04). Ruptured AVMs had significantly shorter TT10%-100% compared to unruptured AVMs (P = .05).

CONCLUSION

TT on DSA correlates with cerebral AVM flow measured using QMRA and with AVM angioarchitecture and hemorrhagic presentation. Thus, TT may be used to indirectly estimate AVM flow during angiography in real-time and may also be an indicator of important AVM characteristics associated with outflow resistance and increased rupture risk, such as venous stenosis.
Geneva (1400–1600)
Authors: Caesar Mathieu
Published: May 2017

The settlement of human societies on the shore of Lake Geneva, at the mouth of the river Rhône, dates back to prehistorical times. Due to its strategic location and the fact that a bishopric was installed in the city at the beginning of the fifth century, Geneva rapidly developed into an important economic and political center. During the late Middle Ages, and especially from the fifteenth century, the city took advantage of the dominion of the House of Savoy and of the absence of wars in the region. The commercial development promoted by the dukes of Savoy, who supported and protected commercial traffic over the Alps, boosted Geneva’s economic growth. The subsequent development of international trade fairs and the presence of many Italian merchant-bankers (Milanese and Tuscans in particular) made Geneva one of the most important centers of the European Renaissance economy. The city’s economic development was accompanied by substantial demographic growth. The city of 5,000 inhabitants at the beginning of the fifteenth century grew to 10,000 people by the 1460s. The growth continued during the sixteenth century as a result of Protestants taking refuge in the Reformed Republic, and by the beginning of the seventeenth century, Geneva had 17,000 to 18,000 inhabitants. Difficulties faced by the duchy of Savoy and the expansion of the Swiss Confederacy plunged the city, by the 1470s, into economic and political crisis. During the 1520s and 1530s, Geneva allied to the Swiss Cantons, acquired political independence from the bishop, and adopted the Reformed faith (1536). The institution of Calvin’s Church, and the city’s conflicts with Bern and the duchy of Savoy, created a climate of great uncertainty and many conflicts, which ended only with the Peace of Saint-Julien (1603). Traditional Swiss scholarship considers the Reformation to have been the watershed between the medieval city and the early modern independent Republic. This dividing line has influenced historiographic production, with only a few works analyzing a given topic across the fifteenth and sixteenth centuries. While economic history generated many important studies during the 1960s and 1970s, religious and social history, especially related to Calvin’s Geneva (roughly 1540–1570), have largely dominated the Genevan bibliography. More recently, political and urban history, especially concerning the late medieval period, have received renewed attention. For more resources on Calvin’s Geneva, see the Oxford Bibliographies article in Renaissance and Reformation on “John Calvin” and “Calvinism.” Given the city’s close ties with the Swiss Confederacy, a valuable bibliography is also provided by the Oxford Bibliographies article in Renaissance and Reformation on “Switzerland.”
Ecological Informatics
Authors: Recknagel Friedrich
Published: May 2017

The emerging discipline of ecological informatics takes into account the data-intensive nature of ecology, the precious information content of ecological data, and the growing capacity of computational technology to leverage complex data as well as the critical need for informing sustainable management of complex ecosystems. It comprehends novel concepts and techniques for image- and genome-based monitoring, data management, data analysis, synthesis, and forecasting.
Tumor Progression Following Petroclival Meningioma Subtotal Resection: A Volumetric Study
Authors: Hunter Jacob B , O’Connell Brendan P , Carlson Matthew L , Chambless Lola C , Yawn Robert J , Wang Ray , Mistry Akshitkumar , Thompson Reid C , Weaver Kyle D , Wanna George B
Published: May 2017

BACKGROUND

One study has investigated postoperative growth rates following subtotal resection of petroclival meningiomas utilizing linear measurements, which are insensitive to the multidimensional complex growth of meningiomas, to estimate tumor volume.

OBJECTIVE

To describe petroclival meningioma growth patterns following less-than-complete resection utilizing volumetric analysis and to identify variables associated with tumor progression.

METHODS

Patients with surgically resected WHO grade I petroclival meningiomas were retrospectively reviewed (1999-2015). Image analysis software was utilized to perform volumetric analyses of tumor size and growth on serial MRI studies. The impact of preoperative and postoperative variables on tumor growth after subtotal resection was analyzed. An increase in tumor volume of at least 20% was defined as “tumor growth.”

RESULTS

Twenty-three patients had immediate preoperative and serial postoperative MRI studies available for review. The mean preoperative tumor volume was 20.9 cm3 (range 0.4-54.6). The mean extent of resection was 75.5% (range 31.5%-100.0%). At a mean follow-up of 24.8 mo, 12 tumors (66.7%) exhibited radiological tumor growth, while 6 tumors did not change in size. The median annual volumetric growth rate was 2.82 cm3/yr (range –0.34 to 10.1). Extent of resection and immediate postoperative tumor volume were significantly correlated with the annual volumetric growth rate following resection. At last follow-up, 3 (13%) patients required further intervention.

CONCLUSION

The majority of petroclival meningiomas exhibit growth following subtotal resection. Extent of resection is strongly associated with risk for disease progression following surgery.
Household Debt and Business Cycles Worldwide*
Authors: Mian Atif , Sufi Amir , Verner Emil
Published: May 2017

An increase in the household debt to GDP ratio predicts lower GDP growth and higher unemployment in the medium run for an unbalanced panel of 30 countries from 1960 to 2012. Low mortgage spreads are associated with an increase in the household debt to GDP ratio and a decline in subsequent GDP growth, highlighting the importance of credit supply shocks. Economic forecasters systematically over-predict GDP growth at the end of household debt booms, suggesting an important role of flawed expectations formation. The negative relation between the change in household debt to GDP and subsequent output growth is stronger for countries with less flexible exchange rate regimes. We also uncover a global household debt cycle that partly predicts the severity of the global growth slowdown after 2007. Countries with a household debt cycle more correlated with the global household debt cycle experience a sharper decline in growth after an increase in domestic household debt.
Managing kidney transplant recipients in primary care
Authors: Roth Shira
Published: May 2017

Patients who have undergone kidney transplant are at increased risk for heart disease, new-onset diabetes, metabolic syndrome, and certain malignancies, in addition to opportunistic infections associated with immunosuppression. This article describes guidelines for routine management of kidney transplant recipients in primary care, as well as how to recognize risk factors and complications.
An Interprofessional Course on Substance Use Disorders for Health Professions Students
Authors: Muzyk Andrew J. , Tew Chris , Thomas-Fannin Allie , Dayal Sanjai , Maeda Reina , Schramm-Sapyta Nicole , Andolsek Kathryn M. , Holmer Shelley
Published: May 2017

Problem

Substance use disorders (SUDs) affect millions of Americans. Nevertheless, there is insufficient health care resource allocation for these patients. One reason may be the lack of education and training about SUDs in health professions programs.

Approach

The authors developed a required, interprofessional SUDs course for health professions students completing a one-month psychiatry clerkship within the Duke University Health System starting in November 2015. Students participated in six 1-hour class sessions led by an interdisciplinary faculty. Sessions focused on core areas in SUDs education and used either a lecture with discussion or a small-group team-based learning format. Students completed one motivational interview, attended a 12-step recovery meeting, and wrote a reflection paper. On the first and last day of the clerkship, students measured their attitudes toward individuals with SUDs using the Substance Abuse Attitude Scale (SAAS) and toward interprofessionalism using the Interprofessional Attitudes Scale (IPAS).

Outcomes

Seventy-one students participated in the course from November 2015 to May 2016. Fifty-nine (83%) students had paired pre- and postcourse SAAS and IPAS data. On the SAAS, students showed significant improvement in their median total score and nonmoralizing, treatment optimism, and treatment intervention scores. On the IPAS, students showed significant improvement in their median score on the teamwork, roles, and responsibilities domain.

Next Steps

The authors will continue to assess the course. Starting in academic year 2016–2017, the course will include four additional elements, and beginning in July 2016, accelerated bachelor of science in nursing students will participate in the course.
Omega-6:Omega-3 PUFA Ratio, Pain, Functioning, and Distress in Adults With Knee Pain
Authors: Sibille Kimberly T. , King Christopher , Garrett Timothy J. , Glover Toni L. , Zhang Hang , Chen Huaihou , Reddy Divya , Goodin Burel R. , Sotolongo Adriana , Petrov Megan E. , Cruz-Almeida Yenisel , Herbert Matthew , Bartley Emily J. , Edberg Jeffrey C. , Staud Roland , Redden David T. , Bradley Laurence A. , Fillingim Roger B.
Published: May 2017

Objectives:

Osteoarthritis (OA) is associated with inflammation, chronic pain, functional limitations, and psychosocial distress. High omega-3 (n-3) polyunsaturated fatty acids (PUFAs) are associated with lower levels of inflammatory mediators, anti-nociception, and adaptive cognitive/emotional functioning. High omega-6 (n-6) PUFAs are associated with inflammation, nociception, and psychological distress. While findings related to n-3 supplementation in knee OA are mixed, consideration of the n-6:n-3 ratio and additional outcome measures may provide improved understanding of the potential relevance of these fatty acids in OA. On the basis of recommended and typical ranges of the n-6:n-3 ratio, we hypothesized that in adults with knee pain, those with a high n-6:n-3 ratio would have greater pain/functional limitations, experimental pain sensitivity, and psychosocial distress compared with those with a low n-6:n-3 ratio.

Materials and Methods:

A cross-sectional investigation of clinical and experimental pain and physical and psychosocial functioning was completed in 167 adults ages 45 to 85 meeting knee OA screening criteria. Blood samples were collected and the plasma n-6:n-3 PUFA ratio determined. Quartile splits were computed and low (n=42) and high (n=41) ratio groups were compared.

Results:

The high ratio group reported greater pain and functional limitations, (all Ps<0.04), mechanical temporal summation (hand and knee, P<0.05), and perceived stress (P=0.008) but not depressive symptoms.

Discussion:

In adults with knee pain, a high n-6:n-3 ratio is associated with greater clinical pain/functional limitations, experimental pain sensitivity, and psychosocial distress compared with a low ratio group. Findings support consideration of the n-6:n-3 PUFA ratio and additional clinical endpoints in future research efforts.
Continuous Femoral Nerve Catheters Decrease Opioid-Related Side Effects and Increase Home Disposition Rates Among Geriatric Hip Fracture Patients
Authors: Arsoy Diren , Gardner Michael J. , Amanatullah Derek F. , Huddleston James I. , Goodman Stuart B. , Maloney William J. , Bishop Julius A.
Published: May 2017

Objective:

To evaluate the effect of continuous femoral nerve catheter (CFNC) for postoperative pain control in geriatric proximal femur fractures compared with standard analgesia (SA) treatment.

Design:

Retrospective comparative study.

Setting:

Academic Level 1 trauma center.

Patients/Participants:

We retrospectively identified 265 consecutive geriatric hip fracture patients who underwent surgical treatment.

Intervention:

One hundred forty-nine patients were treated with standard analgesia without nerve catheter whereas 116 patients received an indwelling CFNC.

Main Outcome Measurement:

Daily average preoperative and postoperative pain scores, daily morphine equivalent consumption, opioid-related side effects and discharge disposition.

Results:

Patients with CFNC patients reported lower average pain scores preoperatively (1.9 ± 1.7 for CFNC vs. 4.7 ± 2 for SA; P < 0.0001), on postoperative day 1 (1.5 ± 1.6 for CFNC vs. 3 ± 1.7 for SA; P < 0.0001) and postoperative day 2 (1.2 ± 1.5 for CFNC vs. 2.6 ± 2.1 for SA; P < 0.0001). CFNC group consumed 39% less morphine equivalents on postoperative day 1 (4.4 ± 5.8 mg for CFNC vs. 7.2 ± 10.8 mg for SA; P = 0.005) and 50% less morphine equivalent on postoperative day 2 (3.4 ± 4.4 mg for CFNC vs. 6.8 ± 13 mg for SA; P = 0.105). Patients with CFNC had a lower rate of opioid-related side effects compared with patients with SA (27.5% for CFNC vs. 47% for SA; P = 0.001). More patients with CFNC were discharged to home with or without health services than patients with SA (15% for CFNC vs. 6% for SA; P = 0.023).

Conclusion:

Continuous femoral nerve catheter decreased daily average patient-reported pain scores, narcotic consumption while decreasing the rate of opioid-related side effects. Patients with CFNC were discharged to home more frequently.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Immediate Regrafting of the Split Thickness Skin Graft Donor Site Assists Healing
Authors: Bradow Brian P. , Hallock Geoffrey G. , Wilcock Samuel P.
Published: May 2017

Background:

Delayed or even lack of healing of a split-thickness skin graft (STSG) donor site is a potential problem with elderly patients or those with poor wound healing capabilities. A proactive solution that may minimize this risk is to regraft that donor site using otherwise discarded skin graft remnants.

Methods:

A prospective, nonrandomized, consecutive study was designed to compare the time to healing of the commonly used anterior thigh STSG donor site in patients who had routine dressings (n = 113) versus those with comorbidities known to adversely affect wound healing and had planned regrafting (n = 204). Those comorbidities included age (≥65 years), diabetes mellitus, peripheral vascular disease, chronic renal disease, and chronic steroid use.

Results:

The average number of comorbidities in the regrafted subgroup versus those not regrafted was 1.41 and 0.31, respectively. This was considered to be a significant difference (P < 0.0001) confirming the validity in predicting patients at risk for adverse donor-site healing that would benefit by regrafting. The mean time required for donor-site reepithelialization of those regrafted was 17.2 days compared with 17.8 days for those not regrafted (P = 0.2395), which was not significantly different.

Conclusions:

Regrafting the STSG donor site of patients with known comorbidities, that is, those expected to have delayed healing in general, had a mean time to reepithelialization comparable with conventionally treated individuals. This was considered a direct consequence of recycling rather than discarding any excess skin graft materials when so indicated and can be a proactive solution to a potentially cumbersome dilemma.
An Unusual Etiology of Chest Pain in a Patient With a History of Left-Sided Congenital Diaphragmatic Hernia
Authors: Paton Elizabeth A. , Long Leslie J. , Eubanks James W.
Published: May 2017

Congenital diaphragmatic hernia (CDH) is a discontinuity of the diaphragm in which abdominal viscera herniates into the chest (Hedrick & Adzick, 2016). A 16-year-old female patient with a past medical history of a left-sided CDH presented with severe pain to her left upper quadrant and chest. An initial diagnosis was made of a recurrent CDH and subsequent herniation of the left kidney into the thoracic space. Intraoperatively, her previous diaphragmatic repair was found to be intact, but a sharp bony protrusion, determined to be an exostosis of the posterior lateral aspect of one of her ribs, was noted. Rongeurs of this lesion resulted in resolution of this patient's symptoms.
Retrospective population-based study of emergency medical services-attended out-of-hospital cardiac arrests in children in Belgium
Authors: Vandeplassche Sophie , van de Voorde Patrick
Published: May 2017

Objective

This study presents an analysis of clinical data of the circumstances and outcome of paediatric (0–16 years) out-of-hospital cardiac arrests (p-OHCA) in Belgium.

Methods

This was a retrospective study of a prospective population-based registration of physician-attended [mobile emergency group (MUG)] emergency medical services (EMS) interventions of p-OHCA in Belgium between 2010 and 2012.

Results

We identified 365 OHCA in 18 295 paediatric MUG interventions (2%). Cardiopulmonary resuscitation was performed in 260 (71.2%) cases. In 59.2%, a medical problem was presumed to be underlying. In 106 (40.7%) cases, an ‘external’ cause (e.g. trauma) was the reason for the OHCA. Eventually, 133 children were transported to the emergency department, with return-of-spontaneous-circulation (ROSC) in 42 cases. In the group with initial shockable rhythm (n=13), sustained ROSC was obtained in 69.2%. For those with an initial nonshockable rhythm, the prognosis was much more reserved (13.4% sustained ROSC). This number is in contrast to the high number of children who are transported from scene (51.2%). Importantly, 40.6% of the latter were proclaimed ‘dead’ during transport.

Conclusion

p-OHCA remains rare. Typically, Belgian MUGs each encounter less than two p-OHCA yearly, thus inducing a risk of being insufficiently prepared. Compared with other countries, cardiopulmonary resuscitation was not started in more cases. Even so, in many other cases, children were transported from scene to be proclaimed ‘dead’ very soon after, pointing to a practice of ‘slow code’. This study provides ‘real-life’ data on p-OHCA in Belgium. As it is based on an administrative registry, it lacks information on individual cases. Large population-based registries are needed to further guide our decision making.
Assessing Self-concept as a Mediator Between Anger and Resilience in Adolescents With Cancer in Taiwan
Authors: Wu Wei-Wen , Chang Joanne T. , Tsai Shao-Yu , Liang Shu-Yuan
Published: May 2017

Background:

Anger is considered a common method used by patients to relieve emotional frustrations. However, this emotional response is not a common research focus for adolescents with cancer.

Objective:

The aim of this study was to determine whether self-concept mediated the relationship between anger and resilience for adolescent patients currently being treated for cancer.

Methods:

A cross-sectional study of 40 adolescents with cancer was conducted. The instruments included the Chinese Beck Self-Concept Inventory, the Chinese Beck Anger Inventory, and the Chinese Resilience Scale. Mediation analysis was also conducted.

Results:

The results indicate that (1) variations in anger significantly account for 6.86% of observed variations in self-concept, (2) variations in self-concept significantly account for 52.83% of observed variations in resilience, (3) variations in anger significantly account for 10.96% of observed variations in resilience, and (4) when paths in conditions 1 and 2 were controlled, variations in anger through self-concept significantly account for 54.04% of observed variations in resilience, and variations in anger did not significantly account for observed variations in resilience.

Conclusions:

Gender and age might affect anger control. Despite worse physical functioning and an impacted appearance, participants had normative-to-positive self-concept levels, suggesting that their self-concept might not be affected by cancer. Self-concept might play a mediating role between anger and resilience, thus helping to bridge this knowledge gap.

Implications for Practice:

The current gap in knowledge regarding the mediating relationship necessitates the implementation of a large-scale study designed to verify the mediating role of self-concept between anger and resilience.
Virtual Monoenergetic Imaging and Iodine Perfusion Maps Improve Diagnostic Accuracy of Dual-Energy Computed Tomography Pulmonary Angiography With Suboptimal Contrast Attenuation
Authors: Leithner Doris , Wichmann Julian L. , Vogl Thomas J. , Trommer Jesko , Martin Simon S. , Scholtz Jan-Erik , Bodelle Boris , De Cecco Carlo N. , Duguay Taylor , Nance John W. , Schoepf U. Joseph , Albrecht Moritz H.
Published: May 2017

Objectives

The aim of this study was to investigate the impact of virtual monoenergetic imaging (VMI+) and dual-energy computed tomography perfusion maps (DECT-PMs) on reader confidence and diagnostic accuracy in dual-energy computed tomography pulmonary angiography (DE-CTPA) studies with suboptimal contrast attenuation, compared with standard linearly blended reconstruction series.

Materials and Methods

Dual-energy computed tomography pulmonary angiography examinations with suboptimal contrast attenuation of 68 patients with suspected pulmonary embolism (PE) were included in this institutional review board–approved retrospective study. Virtual monoenergetic imaging series at 40 keV, DECT-PM, and linearly blended images (M_0.6, 60% 90-kV spectrum) were reconstructed. Contrast-to-noise ratio and signal-to-noise ratio within the pulmonary trunk were calculated. Four independent radiologists assessed the presence of PE and their diagnostic confidence using 3 DE-CTPA reconstruction protocols: protocol 1, M_0.6 images; protocol 2, M_0.6 series and DECT-PM; and protocol 3, M_0.6, DECT-PM, and VMI+ series. Receiver operating characteristic (ROC) analysis was performed.

Results

Fourteen patients showed central and 29 segmental PE. Greater contrast-to-noise ratio and signal-to-noise ratio values were measured in VMI+ series at 40 keV in comparison to M_0.6 images (P < 0.001). Diagnostic accuracy for segmental PE detection was as follows: protocol 1 (69.1%); protocol 2 (86.8%); and protocol 3 (92.6%). Protocol 3 resulted in a significantly greater area under the curve for diagnosing segmental PE (0.991, P ≤ 0.033), compared with protocol 1 and 2 (0.897 and 0.951, respectively), and provided the highest diagnostic confidence (P < 0.001).

Conclusions

A reconstruction protocol including 40-keV VMI+ series and DECT-PM improves reader confidence and diagnostic accuracy for segmental PE detection compared with standard M_0.6 images in DE-CTPA with suboptimal contrast attenuation.
Functional Standards for Optimal Aging
Authors: Laflin Molly , Lewis Carole
Published: May 2017

The Moving Target Screen, a performance-based functional assessment tool for adults older than 50 years, is designed to be used by exercise specialists to evaluate the 5 key aspects of fitness central to optimal aging: posture, flexibility, balance, endurance, and strength. The strength of evidence supporting each of the 15 tests that comprise the Moving Target Screen is described. The assessments require inexpensive, standard equipment used by physical and occupational therapists. The Moving Target Screen can be a powerful tool that provides a comprehensive picture of a person's function before disability and problems begin or progress. It is also useful in documenting functional changes.
Horizontal and vertical species turnover in tropical birds in habitats with differing land use
Authors: Sreekar Rachakonda , Corlett Richard T. , Dayananda Salindra , Goodale Uromi Manage , Kilpatrick Adam , Kotagama Sarath W. , Koh Lian Pin , Goodale Eben
Published: May 2017

Large tracts of tropical rainforests are being converted into intensive agricultural lands. Such anthropogenic disturbances are known to reduce species turnover across horizontal distances. But it is not known if they can also reduce species turnover across vertical distances (elevation), which have steeper climatic differences. We measured turnover in birds across horizontal and vertical sampling transects in three land-use types of Sri Lanka: protected forest, reserve buffer and intensive-agriculture, from 90 to 2100 m a.s.l. Bird turnover rates across horizontal distances were similar across all habitats, and much less than vertical turnover rates. Vertical turnover rates were not similar across habitats. Forest had higher turnover rates than the other two habitats for all bird species. Buffer and intensive-agriculture had similar turnover rates, even though buffer habitats were situated at the forest edge. Therefore, our results demonstrate the crucial importance of conserving primary forest across the full elevational range available.
Emergence of leadership in a robotic fish group under diverging individual personality traits
Authors: Wang Chen , Chen Xiaojie , Xie Guangming , Cao Ming
Published: May 2017

Variations of individual’s personality traits have been identified before as one of the possible mechanisms for the emergence of leadership in an interactive collective, which may lead to benefits for the group as a whole. Complementing the large number of existing literatures on using simulation models to study leadership, we use biomimetic robotic fish to gain insight into how the fish’s behaviours evolve under the influence of the physical hydrodynamics. In particular, we focus in this paper on understanding how robotic fish’s personality traits affect the emergence of an effective leading fish in repeated robotic foraging tasks when the robotic fish’s strategies, to push or not to push the obstacle in its foraging path, are updated over time following an evolutionary game set-up. We further show that the robotic fish’s personality traits diverge when the group carries out difficult foraging tasks in our experiments, and self-organization takes place to help the group to adapt to the level of difficulties of the tasks without inter-individual communication.
Mobulid rays feed on euphausiids in the Bohol Sea
Authors: Rohner Christoph A. , Burgess Katherine B. , Rambahiniarison Joshua M. , Stewart Joshua D. , Ponzo Alessandro , Richardson Anthony J.
Published: May 2017

Mobulid rays have a conservative life history and are caught in direct fisheries and as by-catch. Their subsequent vulnerability to overexploitation has recently been recognized, but fisheries management can be ineffective if it ignores habitat and prey preferences and other trophic interactions of the target species. Here, we assessed the feeding ecology of four mobulids (
Manta birostris
,
Mobula tarapacana
,
M. japanica
,
M. thurstoni
) in the Bohol Sea, Philippines, using stomach contents analysis of fisheries specimens landed between November and May in 2013–2015. We show that the mobulids feed heavily on euphausiid krill while they are in the area for approximately six months of the year. We found almost no trophic separation among the mobulid species, with
Euphausia diomedeae
as the major prey item for all species, recorded in 81 of 89 total stomachs (91%).
Mobula japanica
and
M. thurstoni
almost exclusively had this krill in their stomach, while
M. tarapacana
had a squid and fish, and
Ma. birostris
had myctophid fishes and copepods in their stomachs in addition to
E. diomedeae
. This krill was larger than prey for other planktivorous elasmobranchs elsewhere and contributed a mean of 61 364 kcal per stomach (±105 032 kcal s.e., range = 0–631 167 kcal). Our results show that vertically migrating mesopelagic species can be an important food resource for large filter feeders living in tropical seas with oligotrophic surface waters. Given the conservative life history of mobulid rays, the identification of common foraging grounds that overlap with fishing activity could be used to inform future fishing effort.
The contact process on scale-free networks evolving by vertex updating
Authors: Jacob Emmanuel , Mörters Peter
Published: May 2017

We study the contact process on a class of evolving scale-free networks, where each node updates its connections at independent random times. We give a rigorous mathematical proof that there is a transition between a phase where for all infection rates the infection survives for a long time, at least exponential in the network size, and a phase where for sufficiently small infection rates extinction occurs quickly, at most polynomially in the network size. The phase transition occurs when the power-law exponent crosses the value four. This behaviour is in contrast with that of the contact process on the corresponding static model, where there is no phase transition, as well as that of a classical mean-field approximation, which has a phase transition at power-law exponent three. The new observation behind our result is that temporal variability of networks can simultaneously increase the rate at which the infection spreads in the network, and decrease the time at which the infection spends in metastable states.
Trajectory energy minimization for cell growth tracking and genealogy analysis
Authors: Hu Yin , Wang Su , Ma Nan , Hingley-Wilson Suzanne M. , Rocco Andrea , McFadden Johnjoe , Tang Hongying Lilian
Published: May 2017

Cell growth experiments with a microfluidic device produce large-scale time-lapse image data, which contain important information on cell growth and patterns in their genealogy. To extract such information, we propose a scheme to segment and track bacterial cells automatically. In contrast with most published approaches, which often split segmentation and tracking into two independent procedures, we focus on designing an algorithm that describes cell properties evolving between consecutive frames by feeding segmentation and tracking results from one frame to the next one. The cell boundaries are extracted by minimizing the distance regularized level set evolution (DRLSE) model. Each individual cell was identified and tracked by identifying cell septum and membrane as well as developing a trajectory energy minimization function along time-lapse series. Experiments show that by applying this scheme, cell growth and division can be measured automatically. The results show the efficiency of the approach when testing on different datasets while comparing with other existing algorithms. The proposed approach demonstrates great potential for large-scale bacterial cell growth analysis.
Expression of a symbiosis-specific gene in
Symbiodinium
type A1 associated with coral, nudibranch and giant clam larvae
Authors: Mies M. , Voolstra C. R. , Castro C. B. , Pires D. O. , Calderon E. N. , Sumida P. Y. G.
Published: May 2017

Symbiodinium
are responsible for the majority of primary production in coral reefs and found in a mutualistic symbiosis with multiple animal phyla. However, little is known about the molecular signals involved in the establishment of this symbiosis and whether it initiates during host larval development. To address this question, we monitored the expression of a putative symbiosis-specific gene (H
+
-ATPase) in
Symbiodinium
A1
ex hospite
and in association with larvae of a scleractinian coral (
Mussismilia hispida
), a nudibranch (
Berghia stephanieae
) and a giant clam (
Tridacna crocea
). We acquired broodstock for each host, induced spawning and cultured the larvae.
Symbiodinium
cells were offered and larval samples taken for each host during the first 72 h after symbiont addition. In addition, control samples including free-living
Symbiodinium
and broodstock tissue containing symbionts for each host were collected. RNA extraction and RT-PCR were performed and amplified products cloned and sequenced. Our results show that H
+
-ATPase was expressed in
Symbiodinium
associated with coral and giant clam larvae, but not with nudibranch larvae, which digested the symbionts. Broodstock tissue for coral and giant clam also expressed H
+
-ATPase, but not the nudibranch tissue sample. Our results of the expression of H
+
-ATPase as a marker gene suggest that symbiosis between
Symbiodinium
and
M. hispida
and
T. crocea
is established during host larval development. Conversely, in the case of
B. stephanieae
larvae, evidence does not support a mutualistic relationship. Our study supports the utilization of H
+
-ATPase expression as a marker for assessing
Symbiodinium–
invertebrate relationships with applications for the differentiation of symbiotic and non-symbiotic associations. At the same time, insights from a single marker gene approach are limited and future studies should direct the identification of additional symbiosis-specific genes, ideally from both symbiont and host.