bluuebunny/crossref_metadata_2025 huggingface dataset:
On the impact of interhemispheric white matter: Age, executive functioning, and dedifferentiation in the frontal lobes
Authors: Waters Abigail B. , Sawyer Kayle S. , Gansler David A.
Published: June 2018

Introduction

In middle age, declines in executive functioning (EF) are associated with decrements in the quality and/or quantity of white and grey matter. Recruitment of homologous regions has been identified as a compensatory mechanism for cognitive decline in later middle age; however, research into neural substrates of EF has yet to be guided by dedifferentiation models. We hypothesized that frontal‐parietal grey matter volume, interhemispheric white matter, and intrahemispheric white matter fractional anisotropy will be predictive of EF. Further, we hypothesized that the comparative association between interhemispheric white matter and EF will increase with age, because of compensatory recruitment.

Methods

Neurocognitive test data, DTI, and T1 MPRAGE scans (n = 444) were obtained from the NKI‐Rockland Sample. Structural equation modeling was used to examine the relationship between age, EF, interhemispheric white matter (forceps minor; FM), intrahemispheric white matter (superior longitudinal fasciculus; SLF), and a frontal‐parietal grey matter network. EF and grey matter were modelled as latent variables, with EF examined as the criterion. Additionally, a subsample of participants aged 55 to 85 (n = 168) was analyzed to examine the influence of age related compensatory mechanisms.

Results

There was a significant relationship between FM, grey matter, and EF, which was fully mediated by age. There was a significant relationship between SLF and EF, which was not mediated by age. For older adults, only the age‐mediated pathway from FM to EF was significant.

Discussion

Using structural imaging data, support was found for age‐related interhemispheric mechanisms of compensation, but not intrahemispheric mechanisms.
Animacy and real‐world size shape object representations in the human medial temporal lobes
Authors: Blumenthal Anna , Stojanoski Bobby , Martin Chris B. , Cusack Rhodri , Köhler Stefan
Published: June 2018

Identifying what an object is, and whether an object has been encountered before, is a crucial aspect of human behavior. Despite this importance, we do not yet have a complete understanding of the neural basis of these abilities. Investigations into the neural organization of human object representations have revealed category specific organization in the ventral visual stream in perceptual tasks. Interestingly, these categories fall within broader domains of organization, with reported distinctions between animate, inanimate large, and inanimate small objects. While there is some evidence for category specific effects in the medial temporal lobe (MTL), in particular in perirhinal and parahippocampal cortex, it is currently unclear whether domain level organization is also present across these structures. To this end, we used fMRI with a continuous recognition memory task. Stimuli were images of objects from several different categories, which were either animate or inanimate, or large or small within the inanimate domain. We employed representational similarity analysis (RSA) to test the hypothesis that object‐evoked responses in MTL structures during recognition‐memory judgments also show evidence for domain‐level organization along both dimensions. Our data support this hypothesis. Specifically, object representations were shaped by either animacy, real‐world size, or both, in perirhinal and parahippocampal cortex, and the hippocampus. While sensitivity to these dimensions differed across structures when probed individually, hinting at interesting links to functional differentiation, similarities in organization across MTL structures were more prominent overall. These results argue for continuity in the organization of object representations in the ventral visual stream and the MTL.
Exploring 3‐hinge gyral folding patterns among HCP Q3 868 human subjects
Authors: Zhang Tuo , Chen Hanbo , Razavi Mir Jalil , Li Yujie , Ge Fangfei , Guo Lei , Wang Xianqiao , Liu Tianming
Published: June 2018

Comparison and integration of neuroimaging data from different brains and populations are fundamental in neuroscience. Over the past decades, the neuroimaging field has largely depended on image registration to compare and integrate neuroimaging data from individuals in a common reference space, with a basic assumption that the brains are similar. However, the intrinsic neuroanatomical complexity and huge interindividual cortical folding variation remain underexplored. Here we focus on a specific cortical convolution pattern, termed 3‐hinge gyral folding, which is the conjunction of gyri from multiple orientations and has unique and consistent anatomically, structurally, and functionally connective patterns across subjects. By developing a novel shape descriptor and a two‐stage clustering pipeline, we devise an automatic method to identify 3‐hinges in the Human Connectome Project Q3 868 human brains, and further parameterize the complexity of such a pattern and quantify its regularity and variation in terms of 3‐hinge number, position, and morphology. Our results not only exhibit the huge interindividual variations, but also reveal regular relationship between gyral hinges and other factors, such as their locations and cortical morphologies. It is found that “line‐shape” cortices have relatively more consistent 3‐hinge shape pattern distributions, and certain types of 3‐hinge patterns favor particular cortical morphologies. In addition, more 3‐hinges are found on “line‐shape” cortices while their numbers vary more across subjects than those on “non‐line‐shape” cortices. This study adds new insights into a better understanding of the regularity and variability of human brain anatomy, and their functional aspects.
Prognostic effect of sidedness in early stage versus advanced colon cancer
Authors: Kennecke H.F. , Yin Y. , Davies J.M. , Speers C.H. , Cheung W.Y. , Lee‐Ying R.
Published: June 2018

Background and Aims

The prognostic effect of sidedness in colorectal cancer has been evaluated in numerous prospective and retrospective cohorts. Most of these have reported overall survival data; there is scant relapse‐free survival data in early stage disease. This study aimed to determine the effect of tumor sidedness in survival in early stage and relapsed colon cancer.

Methods

Patients with stage I‐III colorectal cancer were identified from the BC Cancer Agency Gastrointestinal Cancer Outcomes Unit. Survival analysis by stage and sidedness was compared with the log‐rank test. Baseline characteristics were controlled by multivariate Cox‐proportional hazard models. In relapsed patients, bevacizumab and EGFR inhibitor (EGFRI) treatments were included and tested for interaction.

Results

Among 5378 patients with stage I‐III colon cancer, patients with right‐sided stage II tumors experienced better relapse‐free survival compared with those with left‐sided tumors; right‐sidedness was not prognostic for RFS in stage III disease. When survival was considered in patients who relapsed, right‐sided tumors had inferior survival after relapse in both stage II and stage III tumors. At relapse, right‐sided outcomes were inferior regardless of biologic therapy. An interaction test revealed a significant association between sidedness and survival with EGFRIs.

Conclusions

In this large, population‐based study, right‐sided presentation has a significant prognostic impact: in early stage, right‐sidedness is favorably prognostic among stage II tumors and not prognostic in stage III disease. After relapse, right‐ sidedness is associated with an inferior prognosis, regardless of initial stage of presentation. Colon tumor sidedness is independently prognostic and may be considered in treatment assignment for both early stage and advanced disease.
Histoplasmosis‐induced ileal perforation in a patient with acquired immune deficiency syndrome: Case report
Authors: Bellido‐Caparó Alvaro , Delgado Málaga Sandra , Garcia Encinas Carlos , Espinoza‐Rios Jorge Luis , Cáceres Pizarro Jaime , Tagle Arróspide Martin
Published: June 2018

Intestinal involvement with disseminated histoplasmosis is common in some populations infected with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), especially in those who come from tropical zones. We report the case of a 29‐year‐old male patient, from a tropical zone, with HIV infection and a CD4 value less than 50 cells/mm3, with a history of abdominal pain, fever, diarrhea, and weight loss. On presentation, he was pale, sweaty, and had abdominal rebound tenderness. Laboratory findings demonstrated microcitic hipocromic anemia, azoemia, and hypoalbuminemia. Abdominal‐X‐rays revealed pneumoperitoneum and air fluid levels. He underwent surgery, and a 1‐cm perforation proximal to ileocecal valve was found. A resection and an ileostomy were performed. Histopathology identified caseating granulomas with yeast, compatible with histoplasmosis. He was treated with anfotericin B plus itraconazol with clinical improvement.
Openness to Experience, Ethical Leadership, and Innovative Work Behavior
Authors: Javed Basharat , Khan Abdul Karim , Arjoon Surendra , Mashkoor Maria , Haque Adnan ul
Published: June 2018

Drawing on trait activation theory, we examine ethical leadership as a boundary condition on the relationship between openness to experience and innovative work behavior. We collected data from 291 subordinates and 51 supervisors to test our theoretical model. Our results suggest that openness to experience was positively related to innovative work behavior. Furthermore, this relationship was only significant when ethical leadership was perceived high as compared to low. Our research contributes to the literatures on innovative work behavior and ethical leadership.
The association of length of hospital stay with readmission after elective pancreatic resection
Authors: Mazmudar Aditya , Castle Joshua , Yang Anthony D. , Bentrem David J.
Published: June 2018

Objective

The aim of this study was to identify if prolonged length of hospital stay was protective for certain post‐discharge complications requiring readmission after pancreatectomy.

Methods

Patients undergoing elective pancreatectomy from 2012 to 2013 were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS‐NSQIP). Multivariate regression analyses were conducted to elucidate the association of length of hospital stay (LOS), in‐hospital complications, and post‐discharge complications with 30‐day hospital readmission.

Results

Mean LOS for the readmitted versus not readmitted cohort was 9.01 and 10.36, respectively (P < 0.001). Approximately half of hospital readmissions occur within 7 days of discharge from the hospital. The readmission rate (after hospital discharge) for patients with any in‐hospital complication was 13.2%. On the other hand, the readmission rate for patients with any post‐discharge complication was 70.8%. Readmission rates were above 85% for patients with the following post‐discharge complications: organ/space surgical site infection (SSI), pneumonia, ventilator dependence greater than 48 h, progressive renal insufficiency, sepsis, and septic shock. In a multivariate logistic regression model, prolonged LOS reduced the odds of any post‐discharge complication requiring readmission (OR = 0.68, P = 0.01). Specifically, prolonged LOS reduced the odds of a post‐discharge organ/space SSI requiring readmission (OR = 0.72, P = 0.02).

Conclusion

Readmission after pancreatectomy primarily occurs due to a new post‐discharge event. Furthermore, increased LOS is protective for readmission for post‐pancreatectomy complications, particularly those due to post‐discharge organ space SSIs. Our findings suggest that solely focusing on reducing LOS in pancreatectomy may lead to the unintended consequence of increasing readmission rates.
Nanostructured Thin Films of Moderately Functionalized PMMA‐b‐PS
Authors: Turgut Hatice , Varadharajan Divya , Dingenouts Nico , Delaittre Guillaume
Published: June 2018

A library of poly(methyl methacrylate)‐block‐polystyrene (PMMA‐b‐PS) block copolymers (BCPs) bearing small amounts (<10 mol%) of functional comonomer in either one or both blocks is investigated for their phase separation behavior in bulk and in thin films. Particularly, functionalities typically involved in modern postpolymerization modifications are considered, e.g., azide, pentafluorophenyl, furfuryl. Small‐angle X‐ray scattering and atomic force microscopy are employed to determine the characteristic dimensional features of lamellae‐forming BCPs, which differ essentially in the functional groups. It is shown that the presence of the reactive moieties does not perturb the ability to phase separate in bulk, yet has an impact on the dimensions of the domains. Using a classic two‐step procedure involving surface neutralization with a statistical PMMA‐co‐PS copolymer, it is observed that some functional copolymers are not able to form homogeneous thin films. Solvent stability and crosslinking ability of the films are then briefly assessed as a first step to establishing the functional films as nanoresolved molecular immobilization platform with feature sizes of 20 nm and below.
Ketone‐Functionalized Polymer Nano‐Objects Prepared via Photoinitiated Polymerization‐Induced Self‐Assembly (Photo‐PISA) Using a Poly(diacetone acrylamide)‐Based Macro‐RAFT Agent
Authors: He Jun , Xu Qin , Tan Jianbo , Zhang Li
Published: June 2018

Herein, ketone‐functionalized diblock copolymer nano‐objects are prepared by photoinitiated reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization of tert‐butyl acrylate (tBA) using a poly(diacetone acrylamide) (PDAAM)‐based macromolecular RAFT (macro‐RAFT) agent in ethanol/water (60/40, w/w) at room temperature. A high polymerization rate is observed via the exposure of visible light (λmax = 405 nm, 0.45 mW cm−2) with near quantitative monomer conversion being achieved within 60 min. A morphological phase diagram is constructed by changing the degree of polymerization (DP) of PtBA and the monomer concentration. The morphologies of polymer nano‐objects are further tuned by incorporating isobornyl acrylate (IBOA) into the core‐forming block. The ketone‐functionalized diblock copolymer nano‐objects can be shell‐cross‐linked by reacting with a diamine. Finally, the shell‐cross‐linked polymer nano‐objects are further hydrolyzed and employed as a template for the synthesis of silver composites.
In Situ Crosslinking of Nanoparticles in Polymerization‐Induced Self‐Assembly via ARGET ATRP of Glycidyl Methacrylate
Authors: Wang Jian , Wu Zhigang , Wang Guowei , Matyjaszewski Krzysztof
Published: June 2018

Polymerization‐induced self‐assembly (PISA) and in situ crosslinking of the formed nanoparticles are successfully realized by activators regenerated by electron‐transfer atom transfer radical polymerization (ARGET ATRP) of glycidyl methacrylate (GMA) or a mixture of GMA/benzyl methacrylate (BnMA) monomers in ethanol. Poly(oligo(ethylene oxide) methyl ether methacrylate) was employed as macroinitiator/stabilizer, and a cupric bromide/tris(pyridin‐2‐ylmethyl)amine complex as catalyst. Tin (2‐ethylhexanoate) was used as reducing agent for ARGET ATRP, and simultaneously acted as a catalyst for ring‐opening polymerization of oxirane ring in GMA. The kinetics shows that the double bond in GMA was completely polymerized in 4.0 h, while only a 33% conversion of oxirane ring in GMA was reached at 117.0 h. Such a large difference would guarantee a smooth PISA and a subsequent in situ crosslinking of formed nanoparticles. The transmission electron microscopy and dynamic light scattering show spherical nanoparticles formed. With a feed molar ratio [BnMA]0/[GMA]0 = 150/50, 100/100, and 50/150, the nanoparticles formed in ethanol can dissociate or swell in toluene. When pure GMA was used, the solid nanoparticles were observed in toluene or ethanol. The ARGET ATRP provides an efficient strategy to stabilize the nanoparticles formed in the PISA of GMA‐containing system.
Über den Einfluss von Werkstoffkennwerten auf das Spanbruchverhalten von bleiarmem Messing
Authors: Hofmann U. , Nobel C. , Baier S. , Buchkremer S. , Döbbeler B. , Klocke F.
Published: June 2018

Bleiarme Messing‐Werkstoffe gewinnen nicht zuletzt wegen verschiedener regulatorischer Initiativen auf nationaler und länderübergreifender Ebene immer mehr an Bedeutung. Ein herabgesetzter Massenanteil Blei in Messing führt bei der spanenden Bearbeitung jedoch zu ungünstigeren Spanformen und –längen beziehungsweise zu einer Vergrößerung der Spanraumzahl, welche ein Maß für das Schüttvolumen von Spänen ist. Auf der Grundlage praxisnaher Zerspanversuche mit unterschiedlichen Kupfer‐Zink‐Blei‐Werkstoffen wird gezeigt, dass ein reduzierter Bleigehalt durch eine Anpassung der Maschineneinstellungen Vorschub und Schnitttiefe kompensiert werden kann. Dazu wird ein phänomenologisches Modell vorgestellt, mit dem die Spanraumzahl aus dem Bleigehalt und den Zerspanungsparametern berechnet werden kann. Demgegenüber liefert diese Arbeit keine Hinweise auf eine signifikante Korrelation zwischen der Spanraumzahl und den Kennwerten aus standardisierten Werkstoffprüfungen, wie etwa dem Zugversuch, der Härtemessung oder der quantitativen Gefügeanalyse.
Analysis of dissimilar friction stir welding process for tensile properties of EN AW 2024 and EN AW 5083
Authors: Kasman Ş.
Published: June 2018

The objective of the present study is to analyze the effect of dissimilar friction stir welding process parameters associated with the tool pin profile. Nine different welding experiments were conducted on EN AW 2024 and EN AW 5083 plates. Each of the welded joints was exposed to metallurgical and mechanical tests to determine the effect of the parameters on the welded joint's strength and characteristics. The welding responses or characteristics were analyzed using the statistical tools, grey relational analysis and analysis of variance. Thus, the contribution of each parameter to the process response (ultimate tensile strength and percentage of elongation) was analyzed, and an optimal welding condition was determined. The results of metallurgical analyses showed that the defective joints were mostly in the welded joints fabricated with a conical threaded pin, and the shape of the stir zone was affected by the pin profile and tool rotational speed. The metallurgical results were consistent with the tensile test results. Statistical analyses showed that the most effective parameter on the welded joint strength and elongation is tool rotational speed with 70.3 %. While the tool pin profile affects the stir zone shape, the strength and elongation are not affected. The effect of welding speed (5.6 %) is not significant on strength and elongation.
Quantitative adiabatic‐refocused INEPT (QA‐RINEPT) as a tool for fast and reliable characterization of polyols
Authors: Sabatino Paolo , Gao Min , Hou Jianbo
Published: June 2018

13C nuclear magnetic resonance (NMR) is a powerful tool for the detailed characterization and structure elucidation of polymeric samples. The low natural abundance and sensitivity of the 13C isotope, however, lead to very long acquisition time, therefore limiting the use of such technique. We report here the implementation of a quantitative method, quantitative adiabatic‐refocused insensitive nuclei enhanced by polarization transfer (QA‐RINEPT), for the characterization of polyol samples. The method, based on the well‐known insensitive nuclei enhanced by polarization transfer sequence, allows the boost in sensitivity of the carbon resonances without sacrificing the quantitative aspects of the analysis. This is achieved controlling the polarization transfer mechanism and introducing a response factor to calculate precisely the sensitivity gain of the different carbon signals. Compared with the standard single pulse quantitative experiment, the QA‐RINEPT method produces up to 4.7× signals enhancement per unit of time. An in‐depth statistical analysis was conducted to confirm the reliability of the QA‐RINEPT method. We show that there is excellent agreement between the new and old 13C‐NMR methods for the quantitative determination of several important polyol properties such as the comonomer and initiator content as well as the ratio of primary and secondary hydroxyl groups.
Dielectric spectroscopic analysis of polyvinyl chloride nanocomposites loaded with Fe2O3 nanocrystals
Authors: Mansour Sh. A. , Elsad R. A. , Izzularab M. A.
Published: June 2018

Iron oxide (α‐Fe2O3) nanocrystals powder was successfully synthesized via the sol‐gel method. The microstructural examination of the synthesized nanocrystals confirmed the formation of α‐Fe2O3 (hematite) structure using X‐ray diffraction and Fourier transform infrared. The synthesized nano‐hematite powder with different weight percentage up to 5 wt% was introduced to polyvinyl chloride (PVC) to fabricate PVC/Fe2O3 nanocomposites using the solution‐cast technique. The dielectric spectroscopic analysis for the investigated samples has been studied at room temperature and at different temperatures up to 120°C. The real part of the permittivity (ε′) exhibited a significant dependence on filler concentrations throughout whole temperature range. However, the dependency of both of the loss tangent (tanδ) and AC conductivity (σac) on filler concentrations is more pronounced at temperatures higher than room temperature. The obtained values of tan δ for the investigated nancomposites referred to the α‐relaxation around 70°C, which is close to glass transition temperature of the investigated PVC. The dependency of the dielectric strength on Fe2O3 nanofiller concentration was observed with enhancement in the dielectric strength reach to 20.5% for PVC/0.7 wt% Fe2O3 nanocomposite higher than the recorded value for the pristine PVC.
Assessing the impact of the new ICD‐10‐CM coding system on pharmacoepidemiologic studies—An application to the known association between angiotensin‐converting enzyme inhibitors and angioedema
Authors: Panozzo Catherine A. , Welch Emily C. , Woodworth Tiffany S. , Huang Ting‐Ying , Her Qoua L. , Gagne Joshua J. , Sun Jenny W. , Rogers Catherine , Menzin Talia J. , Ehrmann Max , Freitas Katherine E. , Haug Nicole R. , Toh Sengwee
Published: June 2018

Purpose

To replicate the well‐established association between angiotensin‐converting enzyme inhibitors versus beta blockers and angioedema in the International Classification of Diseases, 10th Revision, Clinical Modification (ICD‐10‐CM) era.

Methods

We conducted a retrospective, inception cohort study in a large insurance database formatted to the Sentinel Common Data Model. We defined study periods spanning the ICD‐9‐CM era only, ICD‐10‐CM era only, and ICD‐9‐CM and ICD‐10‐CM era and conducted simple‐forward mapping (SFM), simple‐backward mapping (SBM), and forward‐backward mapping (FBM) referencing the General Equivalence Mappings to translate the outcome (angioedema) and covariates from ICD‐9‐CM to ICD‐10‐CM. We performed propensity score (PS)‐matched and PS‐stratified Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

In the ICD‐9‐CM and ICD‐10‐CM eras spanning April 1 to September 30 of 2015 and 2016, there were 152 017 and 145 232 angiotensin‐converting enzyme inhibitor initiators and 115 073 and 116 652 beta‐blocker initiators, respectively. The PS‐matched HR was 4.19 (95% CI, 2.82‐6.23) in the ICD‐9‐CM era, 4.37 (2.92‐6.52) in the ICD‐10‐CM era using SFM, and 4.64 (3.05‐7.07) in the ICD‐10‐CM era using SBM and FBM. The PS‐matched HRs from the mixed ICD‐9‐CM and ICD‐10‐CM eras ranged from 3.91 (2.69‐5.68) to 4.35 (3.33‐5.70).

Conclusion

The adjusted HRs across different diagnostic coding eras and the use of SFM versus SBM and FBM produced numerically different but clinically similar results. Additional investigations as ICD‐10‐CM data accumulate are warranted.
Beyond the bucket list: Unfinished and business among advanced cancer patients
Authors: Masterson Melissa P. , Slivjak Elizabeth , Jankauskaite Greta , Breitbart William , Pessin Hayley , Schofield Elizabeth , Holland Jason , Lichtenthal Wendy G.
Published: June 2018

Objective

The study aims to examine the prevalence and common themes of unfinished business (UB) and its associations with distress among advanced cancer patients.

Methods

A total of 223 patients from a larger randomized controlled trial of Individual Meaning‐Centered Psychotherapy (IMCP) completed self‐report questionnaires that assessed UB and UB‐related distress, hopelessness, desire for hastened death, anxiety and depression, quality of life, spiritual well‐being, and purpose/meaning. Unfinished business themes were identified by qualitative analysis of open‐ended data.

Results

A total of 161 (72%) patients reported the presence of UB. The mean UB‐related distress score was 7.01 (SD = 2.1) out of 10. Results of independent t tests showed that patients with UB reported significantly higher levels of anxiety and lower levels of existential transcendence than patients without UB. Linear regression equations indicated that UB‐related distress significantly predicted hopelessness (F1,154 = 9.54, P < 0.05, R2 = 0.058), anxiety (F1,154 = 4.31, P < 0.05, R2 = 0.027), personal meaning (F1,136 = 6.18, P < 0.05, R2 = 0.043), and existential transcendence (F1,119 = 6.7, P < 0.05, R2 = 0.053). Ten UB themes emerged from open‐ended responses; UB themes were not associated with UB‐related distress or psychological adjustment.

Conclusions

Unfinished business was both prevalent and distressing in our sample. Findings underscore the need to develop and implement interventions designed to help patients resolve or find solace with UB.
Modeling The Effects of Shock Pressure and Pore Morphology on Hot Spot Mechanisms in HMX
Authors: Springer H. Keo , Bastea Sorin , Nichols Albert L. , Tarver Craig M. , Reaugh John E.
Published: June 2018

We investigate the effects of shock pressure and pore morphology on the formation and growth of hot spots in HMX (octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine). Both non‐reactive and reactive ALE3D simulations are used in these studies. Our non‐reactive simulations show a viscous‐dominated pore collapse mode at lower shock pressures (2–10 GPa) with shear band formation and a hydrodynamic‐dominated mode at higher shock pressures (20‐40 GPa) due to bulk melting. When normalized by bulk shock heating, viscous‐dominated pore collapse modes are more efficient at generating hot spots. Pore morphology influences the post‐collapse temperature distributions and reaction rate for a fixed pore area and shock pressure. We find that multiple surface pores at the binder‐grain interface tend to react the fastest. Due to their upstream location in the HMX grain, the surface pores collapse sooner than interior pores; thus, the extent of reaction will generally favor these morphologies because they have more time to grow. In general, multiple smaller hot spots tend to react faster than a single larger hot spot because they accelerate one another's burning. The rank order of morphology effects, however, is not the same for non‐reactive and reactive simulations. For example, while multiple surface pores produce the highest reaction rates they do not produce the highest (non‐reactive) hot spot temperatures. Our numerical studies provide insights on hot spot mechanisms in lieu of direct measurements and can be used to develop advanced shock initiation models.
Global Tensor‐Matter Transitions in F‐Theory
Authors: Dierigl Markus , Oehlmann Paul , Ruehle Fabian
Published: June 2018

We use F‐theory to study gauge algebra preserving transitions of 6d supergravity theories that are connected by superconformal points. While the vector multiplets remain unchanged, the hyper‐ and tensor multiplet sectors are modified. In 6d F‐theory models, these transitions are realized by tuning the intersection points of two curves, one of them carrying a non‐Abelian gauge algebra, to a (4,6,12) singularity, followed by a resolution in the base. The six‐dimensional supergravity anomaly constraints are strong enough to completely fix the possible non‐Abelian representations and to restrict the Abelian charges in the hypermultiplet sector affected by the transition, as we demonstrate for all Lie algebras and their representations. Furthermore, we present several examples of such transitions in torically resolved fibrations. In these smooth models, superconformal points lead to non‐flat fibers which correspond to non‐toric Kähler deformations of the torus‐fibered Calabi‐Yau 3‐fold geometry.
Green tea as a safe alternative approach for nonalcoholic fatty liver treatment: A systematic review and meta‐analysis of clinical trials
Authors: Mansour‐Ghanaei Fariborz , Hadi Amir , Pourmasoumi Makan , Joukar Farahnaz , Golpour Sahar , Najafgholizadeh Ameneh
Published: June 2018

This study aimed to evaluate the efficacy of green tea supplementation on nonalcoholic fatty liver disease treatment.

Electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar, were systematically searched up to October 30, 2017, to identify eligible trials based on the inclusion criteria. The effect size was presented as mean difference with 95% confidence intervals (CI).

The meta‐analysis of data from four studies indicated significant effects of green tea supplementation in altering alanine aminotransferases (−12.81 U/L; 95% CI: −18.17 to −7.45) and aspartate aminotransferases (−10.91 U/L; 95% CI: −19.66 to −2.17) blood concentrations. Likewise, a favorable effect of green tea administration was observed on body mass index (−2.08 kg/cm2; 95% CI: −2.81 to −1.36), triacylglycerol (−31.87 mg/dl; 95% CI: −40.62 to −23.12), total cholesterol (−27.57 mg/dl; 95% CI: −36.17 to −18.98), and low‐density lipoprotein cholesterol (−14.15 mg/dl; 95% CI: −23.69 to −4.60), whereas no significant effect was detected on high‐density lipoprotein cholesterol concentrations (7.41 mg/dl; 95% CI: −1.49 to 16.30) and homeostasis model assessment of insulin resistance (−4.06; 95% CI: −10.22 to 2.09).

This systematic review and meta‐analysis of available trials suggests that there  are potential benefits of green tea supplementation on nonalcoholic fatty liver disease.
Efficient and accurate simulation of the packaging forming process
Authors: Robertsson Kristofer , Borgqvist Eric , Wallin Mathias , Ristinmaa Matti , Tryding Johan , Giampieri Andrea , Perego Umberto
Published: June 2018

To allow for large‐scale forming applications, such as converting paperboard into package containers, efficient and reliable numerical tools are needed. In finite element simulations of thin structures, elements including structural features are required to reduce the computational cost. Solid‐shell elements based on reduced integration with hourglass stabilization is an attractive choice. One advantage of this choice is the natural inclusion of the thickness, not present in standard degenerated shells, which is especially important for many problems involving contact. Furthermore, no restrictions are imposed on the constitutive models since the solid‐shell element does not require the plane stress condition to be enforced. In this work, a recently proposed efficient solid‐shell element is implemented together with a state‐of‐the‐art continuum model for paperboard. This approach is validated by comparing the obtained numerical results with experimental results for paperboard as well as with those found by using 3D continuum elements. To show the potential of this approach, a large‐scale forming simulation of paperboard is used as a proof of concept.
Statistical monitoring of multiple profiles simultaneously using Gaussian processes
Authors: Jahani Salman , Kontar Raed , Veeramani Dharmaraj , Zhou Shiyu
Published: June 2018

Profile monitoring is the application of control charts to monitor the stability of a process over time when the process can be characterized by a functional relationship between a response variable and 1 or more explanatory variables. Most of the research in profile monitoring has been focused on monitoring univariate profiles, while multivariate profile data are widely observed in practice. In this paper, a monitoring approach based on a multivariate Gaussian process (MGP) model is proposed to monitor multivariate profiles simultaneously. In this regard, using a non‐separable covariance function, a MGP model is fitted to represent the baseline in‐control multivariate profile. Then, the stability of the process is tracked by monitoring a distance measure between the new observations of the multivariate profile and the baseline in‐control model. A key advantage of this method is that it considers correlations both within profiles and between profiles. We also introduce, as a benchmark, a univariate Gaussian process‐based profile monitoring scheme modified for multivariate profiles. The performance of the proposed approaches is investigated and compared through numerical studies and a real‐world case study. The analysis confirms the effectiveness of the MGP‐based monitoring scheme for multivariate profiles.
Impact of the complexing cation on the sensitivity of collision‐induced dissociation spectra to fatty acid position for a set of YXY/YYX‐type triglycerides
Authors: Makarov Pavel , Zheng Dong , Le Duc , Evans Jason J.
Published: June 2018

Rationale

The development of an automated platform for the positional analysis of triglycerides based on electrospray ionization tandem mass spectrometry (ESI‐MS/MS) continues to be pursued. This work compares the positional sensitivities of the collision‐induced dissociation (CID) spectra for a representative set of YXY/YYX triglycerides using ammonium, silver, sodium and lithium as complexing agents.

Methods

A set of triglycerides were synthesized and analyzed by ESI‐MS/MS using an ion trap mass spectrometer. Using different salt additives, the product ion spectra of the corresponding precursor ions for twelve systems of the form YXY/YYX, where Y and X represent C16:0, C18:1(c‐9), C18:2(cc‐9,12) and C20:4(cccc‐5,8,11,14), were collected. The data was used to prepare two‐point calibration plots for each of the twelve positional isomer systems using each of the four complexing agents.

Results

The positional sensitivities for all twelve positional isomer systems were robust for both the sodium and lithium TAG adducts. The CID data for both the sodium and lithium TAG adducts are much less sensitive to the degree of unsaturation and double bond position of the fatty acids constituents than the CID data for the ammonium adducts.

Conclusions

Using sodium or lithium TAG adducts may be advantageous for the development of an accurate predictive model for performing positional analysis of complex TAG mixtures based on ESI‐MS/MS. Ammonium adducts are likely complicated by the ability of the ammonium ion to provide extra stability to some precursor ions through hydrogen‐bond‐like interactions.
Kraft's acquisition of Cadbury
Authors: Sharland Alex
Published: June 2018

The case of Kraft Foods attempting to, and eventually succeeding in, acquiring Cadbury, the UK chocolate maker, is replete with the drama and complexity of corporate takeovers. Governments, politicians, unions, customers, and other interest groups all chime in with their version of what is good for their particular interest group. The clash of food giants makes for excellent reading, and trying to determine how successful the combined company will be is a natural question to consider. The strengths of the case lie in the way the context is established, with the history of Cadbury, its culture, and the “soft” power achieved by the founding family explained.
Doodling, Borrowing, and Remixing: Students Inquiring Across Digitized Spaces
Authors: Collier Diane R.
Published: June 2018

Young students must become proficient in the new literacies of 21st‐century technologies to be considered literate. This department explores how literacy educators can integrate information and communication technologies into the curriculum.
Changes in urethral mobility and configuration after prolapse repair
Authors: Wen L. , Shek K. L. , Dietz H. P.
Published: June 2018

Objective

To evaluate changes in urethral mobility and configuration after prolapse repair.

Methods

This was a retrospective study of 92 patients who were examined between 2005 and 2016 before and after surgery for pelvic organ prolapse (POP) without concomitant anti‐incontinence surgery. All patients were assessed with an interview, POP quantification and translabial four‐dimensional ultrasound. Urethral mobility was evaluated using semi‐automated urethral motion profile software in which x‐ and y‐coordinates of six equidistant points along the length of the urethra were determined both at rest and on Valsalva, relative to the posteroinferior margin of the pubic symphysis. Urethral kinking was measured by placing tangents distal and proximal to any visually identified change in the urethral axis. Imaging data obtained before and after prolapse surgery were compared.

Results

Mean age was 58 years and mean follow‐up was 5.8 months. Prolapse symptoms had resolved in 85% of patients. Highly significant reductions in urethral mobility and urethral kinking were seen after surgery (all P ≤ 0.001). Similar changes were observed after anterior vaginal repair with or without apical repair, without concomitant posterior repair (n = 23; all P < 0.05).

Conclusions

POP surgery was associated significantly with ‘straightening’ of the urethra and reduction in urethral mobility. The effect seems to be due largely to cystocele repair. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Fetal exome sequencing: yield and limitations in a tertiary referral center
Authors: Daum H. , Meiner V. , Elpeleg O. , Harel T. ,   collaborating authors
Published: June 2018

Objective

To explore the indications for and diagnostic outcomes of fetal exome sequencing in a tertiary referral center.

Methods

Between 2012 and 2017, 77 unrelated fetal samples from pregnancies referred to our center underwent exome sequencing. The cohort included 37 fetuses, 36 products of conception (from cases of pregnancy termination or intrauterine fetal death), one case with DNA from both the fetus and a previous termination of pregnancy, and three cases with DNA of unknown origin. Exome sequencing was performed on DNA extracted from amniocytes or fetal tissue and, in some cases, from parental peripheral blood. Indications, turnaround time, diagnostic rates and pregnancy outcomes were investigated. Diagnostic yield was analyzed according to consanguinity (yes or no), sample type (proband only, or trio or other) and referral indication (malformation or isolated nuchal translucency (NT)).

Results

The most common indication for fetal exome sequencing was multiple malformations (21/77, 27%), followed by isolated brain malformation (15/77, 19%). Twelve (16%) fetuses were referred for isolated increased NT. Exome analysis was diagnostic for 16 fetuses (21%); when subclassified into fetal malformations vs isolated increased NT it became clear that exome analysis did not reveal any known or probable pathogenic variants in cases referred for isolated increased NT, whereas, among the remaining fetuses, a molecular diagnosis was reached in 16/65 (25%). Proband‐only cases received a diagnosis more often than did cases that had trio exome sequencing.

Conclusions

Exome sequencing has the potential to provide molecular diagnoses in cases in which conventional prenatal cytogenetic testing is negative. Referral bias of consanguineous cases could account for the high diagnostic rate of proband‐only sequencing. Syndrome‐specific prognostic information enables parents to make informed decisions, whereas challenges include time limitations and variant interpretation in the setting of non‐specific fetal findings. As we report only established disease–gene associations, further segregation and functional studies in a research setting are expected to increase significantly the diagnostic yield. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Structural changes in puborectalis muscle after vaginal delivery
Authors: Van de Waarsenburg M. K. , van der Vaart C. H. , Withagen M. I. J.
Published: June 2018

Objective

To evaluate the structural composition of the puborectalis muscle before and at several timepoints after first vaginal delivery, by the use of echogenicity and area measurements, in order to explore its recovery.

Methods

Twenty nulliparous women with a singleton pregnancy underwent 3D/4D transperineal ultrasound assessments at rest, on pelvic floor muscle contraction and on Valsalva maneuver at 12 weeks' gestation and at 1 day and 1, 2, 3, 4, 6, 12, 18 and 24 weeks after vaginal delivery. The puborectalis muscle was delineated for measurements of mean echogenicity (MEP) and area (PMA). To assess changes in MEP and PMA over time, linear mixed model analysis was used. The exact number of days after delivery at each ultrasound examination was used as a covariate.

Results

For all timepoints after delivery, MEP was significantly decreased compared with that at 12 weeks' gestation. MEP values increased significantly over time from 1 day to 24 weeks after delivery. Although not statistically significant, a decrease in MEP was observed between 3 and 4 weeks after delivery for all maneuvers. PMA at rest and on Valsalva maneuver remained constant after delivery.

Conclusion

When compared with measurements taken during pregnancy, a sharp decrease in MEP was observed soon after vaginal delivery, which was most likely caused by stretch trauma to the puborectalis muscle and subsequent formation of (micro) hematoma and edema. Subsequent increases in MEP may reflect the disappearance of hematoma and edema, and also the formation of connective and scar tissue. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Tensor and matrix models: a one-night stand or a lifetime romance?
Authors: Diaz Pablo
Published: June 2018

Abstract

The spectra of energy eigenstates of free tensor and matrix models are organized by Kronecker coefficients and Littlewood-Richardson numbers, respectively. Exploiting recent results in combinatorics for Kronecker coefficients, we derive a formula that relates Kronecker coefficients with a hook shape with Littlewood-Richardson numbers. This formula has a natural translation into physics: the eigenstates of the hook sector of tensor models are in one-to-one correspondence with fluctuations of 1/2-BPS states in multi-matrix models. We then conjecture the duality between both sectors. Finally, we study the Hagedorn behaviour of tensor models with finite rank of the symmetry group and, using similar arguments, suggest that the second (high energy) phase could be entirely described by multi-matrix models.
T-duality and high-derivative gravity theories: the BTZ black hole/string paradigm
Authors: Edelstein José D. , Sfetsos Konstantinos , Sierra-Garcia J. Anibal , López Alejandro Vilar
Published: June 2018

Abstract

We show that the temperature and entropy of a BTZ black hole are invariant under T-duality to next to leading order in M
⋆
− 2
, M
⋆ being the scale suppressing higher-curvature/derivative terms in the Lagrangian. We work in the framework of a twoparameter family of theories exhibiting T-duality, which includes (but goes beyond) String Theory. Interestingly enough, the AdS/CFT correspondence enforces quantization conditions on these parameters. In the particular case of bosonic/heterotic string theory, our results extend those of a classical paper by Horowitz and Welch. For generic (albeit quantized) values of the parameters, it suggests that T-duality might be an interesting tool to constrain consistent low-energy effective actions while entailing physical equivalences outside String Theory. Moreover, it generates a new family of regular asymptotically flat black string solutions in three-dimensions.
Increased Radiation but No Benefits in Pedicle Screw Accuracy With Navigation versus a Freehand Technique in Scoliosis Surgery
Authors: Urbanski Wiktor , Jurasz Wojciech , Wolanczyk Michal , Kulej Miroslaw , Morasiewicz Piotr , Dragan Szymon Lukasz , Zaluski Rafal , Miekisiak Grzegorz , Dragan Szymon Feliks
Published: June 2018

Background

The clinical value of pedicle screws in spinal deformity surgery is well known; however, screw insertion is demanding and sometimes associated with complications. Navigation systems based on intraoperatively obtained three-dimensional (3-D) images were developed to minimize pedicle screw misplacements. However, there is a lack of data confirming superiority of navigation above other techniques. There are also concerns regarding increased radiation used during the procedure.

Questions/purposes

The purposes of this study were (1) to compare accuracy of the two methods of pedicle screws placement: intraoperative 3-D image navigation versus a freehand technique in patients with idiopathic scoliosis; and (2) to assess the radiation dose received by patients with both methods.

Methods

Between 2014 and 2016, 49 patients underwent posterior spinal fusion with all pedicle screw constructs for idiopathic scoliosis performed by two surgeons. The study design involved alternating the use of the freehand technique and navigation to position pedicle screws in consecutive patients, forming groups of 27 patients with 451 navigated screws and 22 patients with 384 screws positioned freehand. The two groups did not differ in age, sex, or magnitude of deformity. Two observers not involved in the treatment evaluated the position of the screws. The pedicle breach was assessed on intraoperatively obtained 3-D O-arm® scans according to a grading system: Grade 0 = no pedicle wall violation; Grade 1 = perforation ≤ 2 mm; Grade 2 = 2 to 4 mm; and Grade 3 = perforation > 4 mm. Grades 0 and 1 were considered properly positioned and Grades 2 and 3 represented malposition.

Results

In terms of accuracy, we found no differences, with the numbers available, between the freehand and navigated groups in terms of the proportion of screws that were properly positioned (96% freehand and 96% in the navigation group, respectively; p = 0.518). Grade 3 pedicle screws were observed only in the freehand group and were all located in the upper thoracic spine. Patients undergoing navigated pedicle screw placement received a greater mean radiation dose than those whose screws were placed freehand (1071 ± 447 mGy-cm versus 391 ± 53 mGy-cm; mean difference, 680 mGy-cm; 95% confidence interval, 217-2053 mGy-cm; p < 0.001).

Conclusions

In patients with moderate idiopathic scoliosis undergoing primary surgery, we did not observe benefits of pedicle screw placement with CT-based navigation, but the patients experienced greater exposure to radiation.

Level of Evidence

Level III, therapeutic study.