bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bootstrap analysis of diffusion tensor and mean apparent propagator parameters derived from multiband diffusion MRI
Authors: Bernstein Adam S. , Chen Nan‐kuei , Trouard Theodore P. 
Published: June 2019

PurposeTo directly compare diffusion metrics derived from multiband (MB) imaging sequences to those derived using a single‐band acquisition.MethodsIn this work, diffusion metrics from DTI and mean apparent propagator MRI derived from a commercial MB sequence with an acceleration factor of 3 are compared with those derived from a conventional diffusion MRI sequence using a novel bootstrapping analysis scheme on oversampled diffusion MRI data. The average parameter values for fractional anisotropy and mean diffusivity derived from DTI, as well as propagator anisotropy and return to origin probability derived from mean apparent propagator MRI, are compared.ResultsFractional anisotropy and propagator anisotropy are very similar when computed from data collected with and without MB, but show minor differences at low and high values of fractional anisotropy/propagator anisotropy. Mean diffusivity values are generally lower in the MB‐derived maps, and return to origin probability is generally higher. The coefficient of variation of each parameter is shown to be slightly higher on average from the maps derived from MB versus single band when the TR is short, and slightly lower when the TR of the MB and single‐band experiments is equal.ConclusionThese results demonstrate that the MB sequence tested in this work provides very similar results to a conventional diffusion MRI sequence. The MB sequence is affected minimally by the slight decrease in SNR associated with the parallel reconstruction and reduced TR, and there are relaxation effects associated with the reduced TR.
Trust is our currency
Authors: Gathright Paul 
Published: June 2019

AbstractIn process safety, our goal is to keep process energy contained, to keep the tiger in the cage. To do so effectively, a team effort is required, including operations, maintenance, engineering, management, contractors, and other relevant organizations. We, as process safety leaders and program owners, are selling a product, driving a transaction that includes ideas, investments, and resource allocation. We could, as many do, use the regulatory requirements to facilitate the transaction. This “push” method of sales is less effective than a “pull” approach where we represent the value of our product to the buyers: our management teams, operations, maintenance, engineering, communities, and shareholders. The currency of this more effective exchange is trust. This article will explore the approach of process safety as a product, where trust is the currency of the exchange, thus leading to greater throughput, as measured by risk reduction. When trust is present, team members feel more empowered, and hold themselves more accountable. They are better able to demonstrate that the tiger is in the cage.
An intelligent HAZOP quantitative analysis method based on deviation duration
Authors: Zhou Guang‐Wen , Yang Xia , Zheng Shi‐Qing , Cheng Xi‐An 
Published: June 2019

AbstractThe limit of deviation duration is regarded as an important evidence of the possibility of deviation bringing hazards to the system. And the limits of deviation duration are different when the different process parameters reaching the hazardous threshold (or design value) caused by the same deviation value. Furthermore, the sequence of hazards occurring in the system after generating deviations, that is, deviation transfer path, is formed by process parameters arranged in an ascending order based on the limit of the deviation duration and devices involved. T‐SDG model has been proposed after improving the SDG model, so as to show the deviation propagation path of quantitative analysis. Besides, the characteristics of deviation propagation has been researched; and the influence of simultaneous deviations on the system has been also analyzed in detail. Meanwhile, superposition effect, offset effect, and offset curve have been put forward in order to ensure the system security.Highlights

In this paper, a quantitative analysis method had been proposed.
The definition of the deviation had been extended.
The propagation path was researched based on when the parameters reaching the threshold.
The influence of the simultaneous occurrence of multiple deviations on the system had researched.
Growth inhibitory activity of biflavonoids and diterpenoids from the leaves of the Libyan Juniperus phoenicea against human cancer cells
Authors: Al Groshi Afaf , Jasim Hiba A. , Evans Andrew R. , Ismail Fyaz M.D. , Dempster Nicola M. , Nahar Lutfun , Sarker Satyajit D. 
Published: June 2019

Three biflavonoids [cupressuflavone (1), amentoflavone (2), and sumaflavone (3)], four diterpenoids [13‐epi‐cupressic acid (4), imbricatholic acid (5), 3‐hydroxy‐sandaracopimaric acid (6), and dehydroabietic acid (7)], and one lignan [β‐peltatin methyl ether (8)] were isolated from the cytotoxic fractions of the extracts of the leaves of the Libyan Juniperus phoenicea L. The structures of these compounds were elucidated by spectroscopic means. Cytotoxicity of compounds 1–6 were assessed against the human lung cancer cell line A549 using the MTT assay. Compounds 1 and 3 showed cytotoxicity against the A549 cells (IC50 = 65 and 77 μM, respectively), whereas compound 2 did not show any activity. Diterpenes 4–6 exhibited weak cytotoxicity against the A549 cells with the IC50 values of 159, 263, and 223 μM, respectively. The cytotoxicity of each compound was compared with the anticancer drug, etoposide (IC50 = 61 μM). Cupressuflavone (1) was evaluated also for cytotoxicity against both the human PC3 cancer cell line and the normal prostate cell line (PNT2), and this compound revealed a high degree of cytotoxic selectivity towards the prostate cancer cells (PC3), with IC50 value of 19.9 μM, without any evidence of cytotoxicity towards the normal prostate cell line (PNT2).
Theoretical predictions of the nitrogen heterocyclic compounds with metal and noble gas (metal = Cu, Ag, Au)
Authors: Wen Mei , Li Zhuo Zhe , Li An Yong 
Published: June 2019

AbstractHere, we report a new type of Ng‐containing compounds formed between the Ng‐M group and nitrogen heterocyclic compounds, (CH2)nHNCuNg+ (n = 2, 3), (CH)4NMNg, and (CH)5NCuNg+ (M = Cu, Ag, Au; Ng = Ar, Kr, Xe). Quantum chemistry computations were carried out to optimize their geometric structures and calculate the dissociation energies, dissociation enthalpy, and dissociation free energy change. The stability of these Ng‐bonding complexes was inspected by investigating the three dissociation processes of the these compounds into (a) Ng, M, and nitrogen heterocycle CnN; (b) CnN + MNg+; and (c) CnNM + Ng, which are all endothermic and nonspontaneous, these dissociation processes are also turned out to be endergonic in nature at standard state. The natural bond orbital, atoms in molecules, and energy decomposition analysis based on the molecular wavefunction show that the M‐Ng and M‐N bonds have some covalent and electrostatic characters.
Network Community Detection on Small Quantum Computers
Authors: Shaydulin Ruslan , Ushijima‐Mwesigwa Hayato , Safro Ilya , Mniszewski Susan , Alexeev Yuri 
Published: June 2019

AbstractIn recent years, a number of quantum computing devices with small numbers of qubits have become available. A hybrid quantum local search (QLS) approach that combines a classical machine and a small quantum device to solve problems of practical size is presented. The proposed approach is applied to the network community detection problem. QLS is hardware‐agnostic and easily extendable to new quantum computing devices as they become available. It is demonstrated to solve the 2‐community detection problem on graphs of sizes of up to 410 vertices using the 16‐qubit IBM quantum computer and D‐Wave 2000Q, and compare their performance with the optimal solutions. The results herein demonstrate that QLS performs similarly in terms of quality of the solution and the number of iterations to convergence on both types of quantum computers and it is capable of achieving results comparable to state‐of‐the‐art solvers in terms of quality of the solution including reaching the optimal solutions.
A Red Emissive Two‐Photon Fluorescence Probe Based on Carbon Dots for Intracellular pH Detection
Authors: Ye Xiaoxue , Xiang Yunhui , Wang Qirong , Li Zhen , Liu Zhihong 
Published: June 2019

AbstractIntracellular pH is closely related with many biological processes, including cellular proliferation, apoptosis, endocytic processes, signal transduction, and enzymatic activity. The use of fluorescent probes has become an essential method for intracellular pH detection, but existing fluorescent probes have substantial limitations, such as requiring tedious synthetic preparation, suffering from an inappropriate response range and insufficiently long emission wavelength. In this work, a red emissive two‐photon fluorescence probe based on carbon dots (pH‐CDs) is fabricated using a facile one‐pot hydrothermal method for the monitoring of intracellular pH. pH‐CDs possess a variety of superior properties, including high selectivity, excellent photostability, and low cytotoxicity. Furthermore, they exhibit a pH‐sensitive response in the range of 1.0–9.0 and a linear range of 3.5–6.5, which is desirable for tracking the pH value in living cells. It is demonstrated that the pH‐dependent fluorescence signal is regulated via switching between aggregation and disaggregation of CDs. More importantly, pH‐CDs can be successfully applied to sense and visualize pH fluctuation in cells, tissue, and zebrafish. These findings suggest that the as‐prepared pH‐CDs probe has significant potential for practical application in living systems.
On the numerical solution of matrix Bessel equations
Authors: Kausel Eduardo , Gravenkamp Hauke 
Published: June 2019

AbstractThis article deals with the numerical evaluation of certain systems of second order differential equations that are analogous in structure to the scalar Bessel equations, i.e. . The governing equation includes three distinct coefficient matrices that we assume to be real, symmetric, and positive definite. However, allowance is also made for G to be semi‐definite. We first review the conditions under which rigorous closed‐form solutions are possible, and this occurs when the various matrices share a common set of eigenvectors, even if not the eigenvalues. We find in that case that the response consists in a linear combination of conventional Bessel functions. More generally, we propose three alternative methods to accomplish the evaluation:

An ascending series solution based on the Frobenius method.
An effective asymptotic solution that provides results in very close agreement with the first method. It is stable and accurate for a wide range of values of the argument ‐ more so than the first method.
A direct numerical integration solution using the fifth order Runge‐Kutta‐Nyström algorithm. It works well, except for some idiosyncrasies that depend on the presence of eigenvalues with widely different magnitudes, as will be explained.
We determined that all of these techniques produce highly accurate response functions when measured in terms of the residual to the differential equation, and in all cases we found that residual to be negligible.
Risk of Malignancy in FDG‐Avid Thyroid Incidentalomas on PET/CT: A Prospective Study
Authors: Abdel‐Halim Chadi Nimeh , Rosenberg Tine , Bjørndal Kristine , Madsen Anders Rørbæk , Jakobsen John , Døssing Helle , Bay Mette , Thomassen Anders , Nielsen Anne Lerberg , Godballe Christian 
Published: June 2019

AbstractBackgroundDue to a substantial risk of malignancy, patients with focal FDG‐avid thyroid incidentalomas (FFTIs) on PET/CT are in most of Denmark referred to Head and Neck Cancer (HNC) fast track programs. The aim of this study was to determine the risk of malignancy in FFTI managed in a HNC fast track program.MethodsA prospective cohort study including all patients with FFTI referred to the HNC fast track program, Odense University Hospital between September 1, 2016 and August 31, 2017. Ultrasonography (US) and fine‐needle aspiration biopsy (FNAB) were intended to be done in all patients. Nodules with cytology of Bethesda 1, 3, 4, 5, or 6 were planned for surgical removal.ResultsA total of 104 patients were included. All patients had US and 101 patients (97%) had FNAB. Forty‐two patients had benign cytology classified as Bethesda 2. The remaining 62 patients underwent surgery except from 11 patients, mainly due to comorbidity. The overall risk of malignancy for patients with FFTI referred to our HNC fast track program was calculated to be 24% (23/95) based on patients with unequivocal cytology and/or histology. The only statistically significant US characteristic to predict malignancy was the appearance of irregular margins with a sensitivity of 47% and specificity of 96%.ConclusionThe risk of malignancy of FFTIs handled in our HNC fast track program is 24%.
Actor-network theory and ethnography: Sociomaterial approaches to researching medical education
Authors: MacLeod Anna , Cameron Paula , Ajjawi Rola , Kits Olga , Tummons Jonathan 
Published: June 2019

Medical education is a messy tangle of social and material elements. These material entities include tools, like curriculum guides, stethoscopes, cell phones, accreditation standards, and mannequins; natural elements, like weather systems, disease vectors, and human bodies; and, objects, like checklists, internet connections, classrooms, lights, chairs and an endless array of others. We propose that sociomaterial approaches to ethnography can help us explore taken for granted, or under-theorized, elements of a situation under study, thereby enabling us to think differently. In this article, we describe ideas informing Actor-Network Theory approaches, and how these ideas translate into how ethnographic research is designed and conducted. We investigate epistemological (what we can know, and how) positioning of the researcher in an actor-network theory informed ethnography, and describe how we tailor ethnographic methods—document and artefact analysis; observation; and interviews—to align with a sociomaterial worldview. Untangling sociomaterial scenarios can offer a novel perspective on myriad contemporary medical education issues. These issues include examining how novel tools (e.g. accreditation standards, assessment tools, mannequins, videoconferencing technologies) and spaces (e.g. simulation suites, videoconferenced lecture theatres) used in medical education impact how teaching and learning actually happen in these settings.
An exploratory study on microaggressions in medical school: What are they and why should we care?
Authors: Espaillat Andre , Panna Danielle K. , Goede Dianne L. , Gurka Matthew J. , Novak Maureen A. , Zaidi Zareen 
Published: June 2019

Introduction Microaggressions and their impact have been documented in minority college students; however, little is known about the experience of medical students. This study reports the prevalence and understanding of microaggressions among medical students at the University of Florida College of Medicine (UFCOM), while gaining insights into experiences of medical students dealing with microaggressions.
Method A nine-question survey was sent out to all medical students at the UFCOM in the spring of 2017 to understand their experiences with microaggressions. The authors used simple statistics and chi-test to analyze the demographic data and an inductive thematic qualitative analysis was performed on the open-ended responses to study medical students’ understanding of the term, experiences, and impact of microaggressions.
Results The response rate was 64% (n = 351/545). Fifty-four percent reported experiencing microaggressions, of those the majority were female students (73% compared with 51% among male students, p = 0.0003); for female students from minority backgrounds this was 68% and for white female students 76% (p = 0.2606). Microaggressions are more common in the second year of medical school (30%), followed by the third year (23%). Most students were able to recognize and identify microaggressions, but some denied the concept existed, attributing concerns about microaggressions to a culture promoting oversensitivity and political correctness. Students described microaggressions related to sexism; religion; skin colour; and ethnicity. Students described indifference, emotional reactions and denial of the event as coping mechanisms.
Conclusion Microaggressions are prevalent on a day-to-day basis among medical students with female students from a
Reliable flight control system architecture for agile airborne platforms: an asymmetric multiprocessing approach
Authors: Majumder Shibarchi , Dalsgaard Nielsen Jens Frederik , Bak Thomas , la Cour-Harbo Anders 
Published: June 2019

AbstractSystem software subsystems in an unmanned aircraft system share hardware resources due to space, weight, and power constraints. Such subsystems have different criticality, requirements, and failure rates, and can cause undesired interference when sharing the same hardware. A component with high failure rate can reduce the reliability of the system unless a fault containment mechanism is adopted.This work proposes an asymmetric multiprocessor architecture to establish isolation at the hardware level for distributed implementation of safety-critical subsystems along with user defined payload subsystems on the same hardware with minimally reduced reliability of the system. To achieve that, subsystems are strategically segregated in separate processors, connected to an on-chip protective interconnect for inter-processor communications. A custom watchdog and reset mechanism are implemented to reset a specific processor without affecting the entire system if required. The architecture is demonstrated on a FPGA chip. In addition, an example of an optimised distribution is provided for a specific flight control system with five subsystems.
CLUSTER CATEGORIES FROM GRASSMANNIANS AND ROOT COMBINATORICS
Authors: BAUR KARIN , BOGDANIC DUSKO , GARCIA ELSENER ANA 
Published: June 2019

The category of Cohen–Macaulay modules of an algebra $B_{k,n}$ is used in Jensen et al. (A categorification of Grassmannian cluster algebras, Proc. Lond. Math. Soc. (3) 113(2) (2016), 185–212) to give an additive categorification of the cluster algebra structure on the homogeneous coordinate ring of the Grassmannian of $k$-planes in $n$-space. In this paper, we find canonical Auslander–Reiten sequences and study the Auslander–Reiten translation periodicity for this category. Furthermore, we give an explicit construction of Cohen–Macaulay modules of arbitrary rank. We then use our results to establish a correspondence between rigid indecomposable modules of rank 2 and real roots of degree 2 for the associated Kac–Moody algebra in the tame cases.
On The Pure Theory of Law
Authors: Kelsen Hans 
Published: June 2019

The Pure Theory of Law is a theory of positive law, not of a definite legal order, but of the law in general. It is a general theory of law. As such it is the most consistent version of that school of jurisprudence which is called legal positivism because it considers as “law” only positive law and refuses to recognize as law any other normative social order even if, in the usage of language, it is called “law”, as e.g. so-called “natural law”.Law is—according to the Pure Theory of Law—by its very nature a definite type of norm. As a “norm” the law is the specific meaning of an act of will directed at a definite human behavior. This meaning is: that men ought to behave in a certain way. Hence an essential presupposition of the Pure Theory of Law as a positivistic theory is the recognition of the fundamental difference between the “ought” and the “is”, between norms and assertions. Assertions describe a certain object; they are true or false; norms are not describing, but prescribing; they are neither true nor false; they are valid or non-valid. Hence it is necessary to distinguish as clearly as possible between legal norms established by the legal authority, and assertions of the science of law about legal norms, the sentences by which this science describes its object.
The decline in China’s fertility level: a decomposition analysis
Authors: Jiang Quanbao , Yang Shucai , Li Shuzhuo , Feldman Marcus W. 
Published: June 2019

AbstractMany factors have contributed to the decline in China’s fertility level. Using China’s population census data from 1990, 2000 and 2010, the present study investigates the factors causing the decline in China’s fertility rate by decomposing changes in two fertility indices: the total fertility rate (TFR) and the net reproduction rate (NRR). The change in the TFR is decomposed into the change in the marital fertility rate (MFR) and the change in the proportion of married women (PMW). Four factors contribute to the change in the NRR. The following are the main findings. A drop in the MFR caused a decrease in the TFR and the NRR between 1989 and 2000. However, the change in MFR increased TFR and NRR between 2000 and 2010. Marriage postponement caused a decline in the fertility level between 1989 and 2000 as well as between 2000 and 2010. The effect of the MFR and marriage postponement varied with age and region and also between urban and rural areas.
Why do Zenker's diverticulae occur more often on the left than the right side?
Authors: Fitchat N A , Maharaj S , Kwete M O 
Published: June 2019

AbstractBackgroundZenker's diverticulum is a pharyngoesophageal outpouching of mucosa and submucosa through Killian's dehiscence.ObjectiveTo investigate the propensity for Zenker's diverticulum to occur on the left side by examining muscle thickness in Killian's dehiscence, and to explore correlations between muscle thickness, sex, height and age.MethodsThe study included 109 Caucasian cadavers, 52 male and 57 female. The mean thickest and thinnest measurements of left medial, left lateral, right medial and right lateral aspects of Killian's dehiscence were calculated. The paired student's t-test was used to determine significance.ResultsThe average left muscle layer was significantly thinner than the right muscle layer, in both medial and lateral aspects. Furthermore, medial muscle thickness was significantly thinner than its respective lateral aspect for both the left and right sides. No correlations were found between muscle thickness and cadavers’ sex, length or stature, or age.ConclusionThere was a significant difference in muscle thickness between the left and right sides of Killian's dehiscence. The findings suggest there is a reason why Zenker's diverticulum occurs predominantly on the left side. The study also showed a significant difference in muscle thickness between the medial and lateral aspects of Killian's triangle.