bluuebunny/crossref_metadata_2025 huggingface dataset:
Design method of a two-phase annular nozzle in cryogenic liquid expander
Authors: Li Hongyang , Li Wen , Zhang Xuehui , Zhu Yangli , Zuo Zhitao , Chen Haisheng
Published: January 2019

The two-phase annular nozzle is a critical component of liquid expanders. It matches the outlet of the first stage and the inlet of the second stage. A design method of two-phase annular nozzle involving a two-step process is proposed. Nonequilibrium effects are introduced by the area factor during the second process. The flashing in two-phase annular nozzle is simulated through the cavitation method and validated by the experimental results of Brookhaven National Laboratory’s nozzle and Hord’s hydrofoil. A forward flashing two-phase annular nozzle and a backward flashing two-phase nozzle are designed with different centerline angle distributions where they show a good agreement with the design. Forward flashing two-phase annular nozzle exhibits high curvature and nonuniformity. Backward flashing two-phase nozzle exhibits lower nonuniformity and a slightly higher boundary layer ratio, which shows a better performance in terms of the nonequilibrium effects.
Methods for comparing durability of immune responses between vaccine regimens in early-phase trials
Authors: Westling Ted , Juraska Michal , Seaton Kelly E. , Tomaras Georgia D. , Gilbert Peter B. , Janes Holly
Published: January 2019

The ability to produce a long-lasting, or durable, immune response is a crucial characteristic of many highly effective vaccines. A goal of early-phase vaccine trials is often to compare the immune response durability of multiple tested vaccine regimens. One parameter for measuring immune response durability is the area under the mean post-peak log immune response profile. In this paper, we compare immune response durability across vaccine regimens within and between two phase I trials of DNA-primed HIV vaccine regimens, HVTN 094 and HVTN 096. We compare four estimators of this durability parameter and the resulting statistical inferences for comparing vaccine regimens. Two of these estimators use the trapezoid rule as an empirical approximation of the area under the marginal log response curve, and the other two estimators are based on linear and nonlinear models for the marginal mean log response. We conduct a simulation study to compare the four estimators, provide guidance on estimator selection, and use the nonlinear marginal mean model to analyze immunogenicity data from the two HIV vaccine trials.
Ghee with Glee: A Study of How Consumers Evaluate Product Packaging
Authors: Chavadi Chandan Andanesh , Vishwanatha M R , Mubeen Samiya
Published: January 2019

The main objective of this empirical study is to comprehend how consumers appraise product packaging. Three quality attributes of packaging – technical, functional and informational - and their influence on consumer satisfaction and loyalty were assessed. The study was conducted on Ghee product packaging, involving 199 family units, using four types of packaging. A total of 398 structured questionnaire was used to collect the data from both the moments (moment of purchase and after usage). Statistical tools such as ‘SPSS’ and ‘AMOS 20’were used to construct and evaluate the sequential chain of quality attributes, satisfaction and loyalty. The results identify the most and least valued quality attributes and what differences persist between the four types of ghee packaging. This study contributes to the body of knowledge in terms of consumers’ purchase experiences with regard to the packed ghee product. The present study provides empirical perspectives to marketing managers, product managers and ad agencies, besides throwing up business implications.
Knowledge and Self-Efficacy Assessment of Residents and Fellows Following Palliative Care Unit Rotation: A Pilot Study
Authors: Burmann Sven Niklas , Neukirchen Martin , Ostgathe Christoph , Beckmann Mingo , Schwartz Jacqueline , Scheer Karin , Klco-Brosius Stephanie , Hense Joerg , Teufel Martin , Tewes Mitra
Published: January 2019

Background:

In Germany, some units of specialized palliative care (SPC) offer a 6- to 12-month rotation for resident physicians (RPs) and fellows from different specialties.

Objective:

This pilot study aimed to evaluate feasibility of assessing palliative care knowledge (PCK) and palliative care self-efficacy (PCSE) using a paper-based questionnaire.

Methods:

Palliative care knowledge and PCSE were assessed by introducing a score, followed by a descriptive analysis (determination of frequency, mean, median, and range) using nonparametric tests (χ2 test, Mann–Whitney U test).

Results:

We assessed 17 RPs following SPC rotation and 16 board-certified specialists (BCSs) who had no experience in SPC from 3 German comprehensive cancer centers. Resident physicians were predominantly enrolled in residency programs of hematology and oncology (n = 6), anesthesiology (n = 6), and psychosomatic medicine (n = 3). Resident physicians rotated between year 1 and 8 of residency. Fifteen RPs (88%) had elected this rotation and 72% preferred 12-month duration. The total PCK score of PCK was 27 (RPs) and 24 (BCSs; P = .002). Mean PCSE scores were 46 (RPs) and 39 (BCSs; P = .016). Of 71% of RPs, only 27% of BCSs knew how support of hospice service was initiated ( P = .004). Participants rated the items as comprehensible (n = 24; 73%), relevant (n = 25; 76%) and the questionnaire as adequately long (n = 23; 70%).

Conclusion:

An improved PCK and PCSE were observed in physicians who rotated through an SPC unit; this resulted in an increased tangibility of local palliative care and hospice services. The questionnaire was comprehensible, relevant in terms of content, and adequate in length for a prospective multicenter survey.
Comparative Outcomes of Block and Cancellous Iliac Bone Grafting in Older Unilateral Alveolar Cleft Patients
Authors: Zhou Wei-Na , Pan Yong-Chu , Tang Yan-Chi , Hou Wei , Wu Da-Ming , Yuan Hua , Wan Lin-Zhong , Du Yi-Fei , Jiang Hong-Bing
Published: January 2019

Objective:

To compare osseous outcomes of block and cancellous iliac bone grafting in older unilateral alveolar cleft patients.

Design:

Retrospective and observational follow-up study.

Setting:

Cleft Lip and Palate Centre, Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, China.

Patients:

Forty-five nonsyndromic patients with unilateral complete alveolar cleft were enrolled in this study (25 patients in block bone graft group and 20 patients in cancellous bone graft group).

Interventions:

In cancellous bone graft group, the alveolar cleft was filled with iliac cancellous bone particulate. In group of block bone graft, the harvested bone block was trimmed and fixed in alveolar defect.

Main Outcome Measures:

A novel method was proposed to investigate the volume and density of residual bone graft at 1-week, 3- and 6-month, 1- and 2-year postoperatively based on cone beam computed tomography scans.

Results:

No difference in bone graft volume was found between 2 groups at 1-week and 3-month postoperatively; however, the residual volume of block bone graft group was significantly larger than that of cancellous bone graft group at 6-month, 1- and 2-year postoperatively. The bone density of block bone graft group was lower at 1-week and 3-month postoperatively but was comparable at 6-month, 1- and 2-year postoperatively. Our method was reliable and accurate to identify the range of residual bone graft when the boundary of grafted bone could not be identified clearly.

Conclusion:

Block bone graft could achieve comparable bone density and retain a greater amount of residual bone comparing to cancellous bone graft.
Evaluating impact damage to fabric-based personal armor by infrared NDT
Authors: Budadin ON , Kozelskaya SO , Kaledin VO , Vavilov VP , Kuimova MV
Published: January 2019

The paper considers the thermo-mechanical mechanism of interaction between the damage agents and armor protection made of polymer fabrics. A simplified mathematical model is proposed to describe the deceleration of a damage agent within an armor fabric due to the dissipation of energy expended on irreversible stretching deformations of fabric fibers, as well as fiber slipping friction and material heating. Woven fabric layers are replaced by solid layers characterized by averaged stiffness and viscosity. A discrete numerical model of a solid material is proposed to reduce a problem with a finite number of degrees of freedom; motion equations are obtained on the basis of the Lagrange equations of the second kind, and for their integration, a stable non-conservative difference scheme is used. The software implementation is based on a functional-object paradigm which allows the modeling of conjugated processes. The parameters of governing equations are identified by using the experimental data. Some illustrative examples of interaction between damage agents and armor barriers with different arrangement of fibers are presented. The proposed model can be used to predict the quality of armor protection with the changing number and location of fibers, as well as to test the armor protection by applying the technique of infrared thermography.
Ex-PRESS mini-shunt implanted in a pregnant patient with iridocorneal endothelial syndrome
Authors: Colás-Tomás Teresa , López Tizón Elena
Published: January 2019

Introduction:

The failure rate of both filtration surgery and of aqueous shunt implantation is higher for iridocorneal endothelial syndrome than in other scenarios, due to the continuous proliferation of abnormal endothelial cells over the trabecular meshwork and the filtration area and also due to the more pronounced cicatrizing response shown by these young patients. We present the first case ever described in the literature of a pregnant patient with iridocorneal endothelial syndrome and uncontrolled ocular hypertension who was implanted an Ex-PRESS mini-shunt.

Clinical case:

A 35-year-old female presented with diminution of vision in the left eye for 2 months. She was 20 weeks pregnant. Her visual acuity was 20/20 in right eye and 20/25 in left eye, and intraocular pressure was 11 mmHg in right eye and 34 mmHg in left eye. Slit lamp biomicroscopic examination revealed no alterations in right eye, whereas left eye showed corectopia and uveal ectropion, stroma of iris’ sectoral atrophy and moderate corneal epithelial edema. Gonioscopy showed some anterior iris synechiae in left eye. Fundus evaluation was normal. Based on clinical features and examination, the diagnosis of left eye iridocorneal endothelial syndrome with decompensated intraocular pressure was made. She was prescribed topical timolol (0.5%) and dorzolamide. As a result of uncontrolled intraocular pressure and the impossibility to prescribe other hypotensive treatment available due to her being pregnant, it was decided to perform surgery in left eye using an Ex-PRESS mini-shunt and Ologen®; 6 months post surgery, intraocular pressure was 9 mmHg with no need for hypotensive treatment. The cornea was transparent, and the patient maintained her left eye visual acuity.

Conclusions:

Ex-PRESS mini-shunt can be considered a surgical option for iridocorneal endothelial syndrome. Its composition allows the ostium to remain open and the device triggers a milder postoperative inflammatory response. In our particular case, taking into account that the subject was a young, phakic, pregnant woman, whose intraocular pressure had to be closely controlled and we had to ensure that her postoperative care included as few drugs and as few reoperations as possible, we thought that using this device was the most appropriate option.
Two weeks post-operative ultrasound examination of radio-cephalic arteriovenous fistulae to predict maturity in a Chinese population
Authors: Guo-Cun Hou , Yong-Hong Yan , Xiu-Li Sun , Yi Hou , Na Yin , Guo-Zhen Feng , Ai-Zhen Chen
Published: January 2019

Aim:

The aim of this study was to assess the accuracy of post-operative ultrasound examination for predicting wrist radio-cephalic arteriovenous fistula maturity.

Methods:

All radio-cephalic arteriovenous fistulas performed in our hospital between October 2015 and December 2017 were included in this study. Ultrasound examination of radio-cephalic arteriovenous fistulas was performed 2 weeks post-surgery. Radio-cephalic arteriovenous fistula maturation was defined as successful cannulation of a fistula with two needles, delivery of blood via the access route at a flow rate ⩾200 mL/min for 4 h, and dialysis via fistulae in at least six consecutive sessions.

Results:

Eighty-two wrist radio-cephalic arteriovenous fistulas were analyzed, of which 13 failed. Cephalic vein diameter >4.285 mm and brachial artery peak systolic velocity >134.75 cm/s were the best post-operative ultrasound predictors of radio-cephalic arteriovenous fistula maturity ( p < 0.001 and p = 0.011, respectively). Receiver-operating characteristic curve analysis showed that the sensitivity and specificity of predicting radio-cephalic arteriovenous fistula maturation were 88.4% and 92.3% for cephalic vein diameter (area under the curve = 0.939), respectively, and 82.9% and 76.9% for brachial artery peak systolic velocity (area under the curve = 0.830), respectively. All assessments predicted radio-cephalic arteriovenous fistula maturity (post-operative positive predictive values: cephalic vein diameter = 98.4%, brachial artery peak systolic velocity = 95%) much better than radio-cephalic arteriovenous fistula failure (post-operative negative predictive values: cephalic vein diameter = 60%, brachial artery peak systolic velocity = 45.5%).

Conclusion:

Two weeks after surgery, a new wrist radio-cephalic arteriovenous fistula with a cephalic vein diameter >4.285 mm was considered suitable for dialysis. A high-risk arteriovenous fistula failure would benefit from early intervention.
Genome-Wide Analysis of Domain-Swap Predicted Products in the Genome of Anti-Stress Medicinal Plant: Ocimum tenuiflorum
Authors: Upadhyay Atul Kumar , Sowdhamini Ramanathan
Published: January 2019

Computational approaches to high-throughput data are gaining importance because of explosion of sequences in the post-genomic era. This explosion of sequence data creates a huge gap among the domains of sequence structure and function, since the experimental techniques to determine the structure and function are very expensive, time taking, and laborious in nature. Therefore, there is an urgent need to emphasize on the development of computational approaches in the field of biological systems. Engagement of proteins in quaternary arrangements, such as domain swapping, might be relevant for higher compatibility of such genes at stress conditions. In this study, the capacity to engage in domain swapping was predicted from mere sequence information in the whole genome of holy Basil ( Ocimum tenuiflorum), which is well known to be an anti-stress agent. Approximately, one-fourth of the proteins of O tenuiflorum are predicted to undergo three-dimensional (3D)-domain swapping. Furthermore, function annotation was carried out on all the predicted domain-swap sequences from the O tenuiflorum and Arabidopsis thaliana for their distribution in different Pfam protein families and gene ontology (GO) terms. These domain-swapped protein sequences are associated with many Pfam protein families with a wide range of GO annotation terms. A comparative analysis of domain-swap-predicted sequences in O tenuiflorum with gene products in A thaliana reveals that around 26% (2522 sequences) are close homologues across the 2 genomes. Functional annotation of predicted domain-swapped sequences infers that predicted domain-swap sequences are involved in diverse molecular functions, such as in gene regulation of abiotic stress conditions and adaptation to different environmental niches. Finally, the positively predicted sequences of A thaliana and O tenuiflorum were also examined for their presence in stress regulome, as recorded in our STIFDB database, to check the involvement of these proteins in different abiotic stresses.
“A Sealed Rectilinear Planet”: The Skyscraper as Vertical Heterot opia in J. G. Ballard’s High-Rise and Ben Wheatley’s Screen Adaptation
Authors: Klein Sascha
Published: January 2019

This article addresses the role of vertical detachment in J. G. Ballard’s novel High-Rise (1975/2006) and its recent screen adaptation by Ben Wheatley (2015) through the lens of Michel Foucault’s concept of heterotopia (1967/1984). In particular, it elucidates the specific pressures and possibilities of high-rise living by drawing on Foucault’s distinction between heterotopias of compensation and illusion as well as by assessing their roles in the residents’ gradual slide into tribal anarchy, as charted by the novel and the film. Throughout, my findings are embedded in the context of modern architecture and urban planning, most notably high-rise housing, in postwar Britain and its reflection in other influential cultural productions of the time. Finally, the idea of heterotopia is championed as central to Ballard’s continual engagement with a ‘dark logic’ inherent in modern architecture and technology. The article thus contributes to ongoing debates on verticality and height as factors in past and current urbanistic schemes and their social and psychological impact as reflected in professional discourses as well as in literary-artistic engagements (see “vertical turn” in Graham & Hewitt, 2013).
A novel method for measuring learning opportunities provided by parents to young children with autism spectrum disorder
Authors: Davlantis Katherine S , Estes Annette , Dawson Geraldine , Rogers Sally J
Published: January 2019

The aim of this study was to develop a measurement approach to assess the learning opportunities provided by parents to their young children with autism spectrum disorder during a free play task and to examine the relationship between learning opportunities and child performance on measures of cognition, autism spectrum disorder symptoms, and language. Participants were 91 children with autism spectrum disorder ages 12–24 months and their parents. Ordinary least squares regression was used. Results showed that children whose parents provided more learning opportunities had significantly higher cognitive scores and significantly higher vocabulary comprehension and production. The psychometric properties of the measurement approach were investigated and results indicated that it may be psychometrically sound.
Dynamic and quasi-static signal separation method for bridges under moving loads based on long-gauge FBG strain monitoring
Authors: Lu Huaxi , Gao Zhicheng , Wu Bitao , Zhou Zhenwei
Published: January 2019

Structural health monitoring is an important means of obtaining the state information of bridges, and the extracted quasi-static strain signal can reflect the stress state of bridges directly. However, the strain signals acquired during the operation stage of bridges are dynamic, and the strain gauges used in the health monitoring system are short (no more than 10 cm), which means they are easily affected by small damage at the installation parts of bridges and thereby the monitoring signal abnormalities occur. A type of externally affixed long-gauge fiber strain gauge is used to monitor the health of bridges, and the dynamic and quasi-static signal separation method for long-gauge strain sensors is studied under different vehicle loads; at the same time, the dynamic monitoring performance of the long-gauge sensor is investigated in this paper. The quasi-static strain signal extracted from the dynamic macro-strain signal can be used to directly monitor the stress status of the bridge. The results show that the method proposed in this paper is feasible for extracting the quasi-static macro-strain from a dynamic long-gauge strain signal.
The impact of water injection and exhaust gas recirculation on combustion and emissions in a heavy-duty compression ignition engine operated on diesel and gasoline
Authors: Pamminger Michael , Wang Buyu , Hall Carrie M , Vojtech Ryan , Wallner Thomas
Published: January 2019

Steady-state experiments were conducted on a 12.4L, six-cylinder heavy-duty engine to investigate the influence of port-injected water and dilution via exhaust gas recirculation (EGR) on combustion and emissions for diesel and gasoline operation. Adding a diluent to the combustion process reduces peak combustion temperatures and can reduce the reactivity of the charge, thereby increasing the ignition-delay and, allowing for more time to premix air and fuel. Experiments spanned water/fuel mass ratios up to 140mass% and exhaust gas recirculation ratios up to 20vol% for gasoline and diesel operation with different injection strategies. Diluting the combustion process with either water or EGR resulted in a significant reduction in nitrogen oxide emissions along with a reduction in brake thermal efficiency. The sensitivity of brake thermal efficiency to water and EGR varied among the fuels and injection strategies investigated. An efficiency breakdown revealed that water injection considerably reduced the wall heat transfer; however, a substantial increase in exhaust enthalpy offset the reduction in wall heat transfer and led to a reduction in brake thermal efficiency. Regular diesel operation with main and post injection exhibited a brake thermal efficiency of 45.8% and a 0.3% reduction at a water/fuel ratio of 120%. The engine operation with gasoline, early pilot, and main injection strategy showed a brake thermal efficiency of 45.0% at 0% water/fuel ratio, and a 1.2% decrease in brake thermal efficiency for a water/fuel ratio of 140%. Using EGR as a diluent reduced the brake thermal efficiency by 0.3% for diesel operation, comparing ratios of 0% and 20% EGR. However, a higher impact on brake thermal efficiency was seen for gasoline operation with early pilot and main injection strategy, with a reduction of about 0.8% comparing 0% and 20% EGR. Dilution by means of EGR exhibited a reduction in nitrogen oxide emissions up to 15 g/kWh; water injection showed only up to 10 g/kWh reduction for the EGR rates and water/fuel ratio investigated.
‘Keen as fuck’: youth participation in qualitative research as ‘parallel projects’
Authors: Lohmeyer Ben Arnold
Published: January 2019

Youth researchers continue to pursue the ideals of youth participation in research. This pursuit reflects a broader concern for the problems of participant-researcher power dynamics in qualitative research. Youth researchers develop and adopt a variety of techniques and ethical principles that attempt to position young people as active research participants. However, these methods and principles have not solved the challenges of participation. In this article, I argue that there is a need to accept that some of the power asymmetries of participation might be unsolvable, and to reposition the power relationship between young people and researchers. A central concern in this article is the paradoxically unethical outcomes produced by adult-centric ethics review processes. I argue that youth participation in qualitative research can be understood as parallel projects and that in doing so researchers can value young people’s reasons for participation. In fact, young people might be ‘keen as fuck’ (participant quote) to participate.
Schutz and Becker on making music together: A note on their respective contributions to the sociology of music
Authors: Segre Sandro
Published: January 2019

This article compares the sociological writings of Schutz and Becker on making music together. Schutz laid stress on the We-relationship resulting from face-to-face performance of music, in which every listener participates with the other listeners, the performers, and the composers. Becker emphasized the existence of taken-for-granted conventions on which cooperative relations between performers are based, in conjunction with other members of the music subcommunity with whom they are engaged in a communication flow. The involved actors may participate in several reciprocally connected worlds of shared experiences, which if jointly considered constitute the art world. The theoretical and conceptual differences between Schutz and Becker, which concern their sociological writings on music, are related to analogous diversities between Phenomenological Sociology and Symbolic Interactionism. Finally, Weber, Honigsheim, and Adorno’s contributions to the sociology of music have been here considered for comparative purposes.
Buformin increases radiosensitivity in cervical cancer cells via cell-cycle arrest and delayed DNA-damage repair
Authors: Chen Ling , Zhang Ting , Liu Qiuli , Tang Mei , Yang Yu’e , Wang Yuan , Qiu Haifeng , Yu Jinjin
Published: January 2019

Buformin is a commonly used hypoglycemic agent, and numerous studies have shown that buformin has potent antitumor effects in several malignancies. In this study, we aimed to assess the cytotoxic effect of buformin combined with ionizing radiation (IR) on two human cervical cancer cell lines (Hela and Siha). Cytotoxicity was detected by colony formation assays; impacts on the cell cycle and apoptosis were detected by flow cytometric analyses. Changes in histone H2AX (γ-H2AX) phosphorylation and impacts on the AMPK/S6 pathway were also explored. Our data show that the combination of buformin and IR had a much stronger antiproliferative effect and resulted in more apoptosis than did buformin or IR alone. Combination treatment with a low dose of buformin (10 µM) and IR (4 Gy) caused G2/M-phase cell cycle arrest. Consistent with these findings, Western blotting showed that the combination of buformin and IR activated AMPK and suppressed S6. In addition, delayed disappearance of γ-H2AX was detected by immunofluorescence in cervical cancer cells treated with buformin plus IR. Taken together, the data indicate that the combination of a low concentration of buformin and IR increases the radiosensitivity of cervical cancer cells via cell cycle arrest and inhibition of DNA repair. Based on these results, we strongly support the use of buformin as an effective agent for improving IR treatment efficiency in the context of cervical cancer.

Impact statement

Our idea originated in the thought of discovering new effects of old drugs. Although this study is a basic research, it is very close to clinical treatment. Flow cytometry and immunofluorescence were used to verify that buformin increases radiosensitivity. We aimed to address one of the thorniest problems in treatment process. Based on discovering new effects of old drugs, it is feasible to use buformin as an anticancer drug in clinical application. This will provide new ideas for clinical treatment.
Measurement Error, GLMs, and Notational Conventions
Authors: Hardin James W. , Carroll Raymond J.
Published: January 2019

This paper introduces additive measurement error in a generalized linear-model context. We discuss the types of measurement error along with their effects on fitted models. In addition, we present the notational conventions to be used in this and the accompanying papers.
Instrumental Variables, Bootstrapping, and Generalized Linear Models
Authors: Hardin James W. , Schmiediche Henrik , Carroll Raymond J.
Published: January 2019

This paper discusses and illustrates the qvf command for fitting generalized linear models. The differences between this new command and Stata's glm command are highlighted. One of the most notable features of the qvf command is its ability to include instrumental variables. This functionality was added specifically to address measurement error but may be utilized by the user for other purposes. The qvf command was developed in the C-language using Stata's new plugin features and executes much faster than the glm ado-file.
The Simulation Extrapolation Method for Fitting Generalized Linear Models with Additive Measurement Error
Authors: Hardin James W. , Schmiediche Henrik , Carroll Raymond J.
Published: January 2019

We discuss and illustrate the method of simulation extrapolation for fitting models with additive measurement error. We present this discussion in terms of generalized linear models (GLMs) following the notation defined in Hardin and Carroll (2003). As in Hardin, Schmiediche, and Carroll (2003), our discussion includes specified measurement error and measurement error estimated by replicate error-prone proxies. In addition, we discuss and illustrate three extrapolant functions.
From the Help Desk: Local Polynomial Regression and Stata Plugins
Authors: Gutierrez Roberto G. , Linhart Jean Marie , Pitblado Jeffrey S.
Published: January 2019

Abstract. Local polynomial regression is a generalization of local mean smoothing as described by Nadaraya (1964) and Watson (1964). Instead of fitting a local mean, one instead fits a local pth-order polynomial. Calculations for local polynomial regression are naturally more complex than those for local means, but local polynomial smooths have better statistical properties. The computational complexity may, however, be alleviated by using a Stata plugin. In this article, we describe the locpoly command for performing local polynomial regression. The calculations involved are implemented in both ado-code and with a plugin, allowing the user to assess the speed improvement obtained from using the plugin. Source code for the plugin is also provided as part of the package for this program.
Speaking Stata: Problems with Tables, Part II
Authors: Cox Nicholas J.
Published: January 2019

Three user-written commands are reviewed as illustrations of different approaches to tabulation problems, each one step beyond what is possible to do directly through official Stata. tabcount is a wrapper for tabdisp written to produce tables that show how often specified values occur or specified conditions are satisfied so that, in particular, tables may include explicit zeros whenever desired. makematrix is designed for situations in which a table of results may be compiled by populating a matrix. matrix list or list may then be used to display the table. groups shows frequencies of combinations of values using list. Users should find these commands to be helpful additions to the toolkit. Programmers may be interested in examples of the wrapper approach, calculating the values to be tabulated before passing them to a workhorse display command. This is the second of two papers on this topic.
Causal Inference with Observational Data
Authors: Nichols Austin
Published: January 2019

Problems with inferring causal relationships from nonexperimental data are briefly reviewed, and four broad classes of methods designed to allow estimation of and inference about causal parameters are described: panel regression, matching or reweighting, instrumental variables, and regression discontinuity. Practical examples are offered, and discussion focuses on checking required assumptions to the extent possible.
Mvdcmp: Multivariate Decomposition for Nonlinear Response Models
Authors: Powers Daniel A. , Yoshioka Hirotoshi , Yun Myeong-Su
Published: January 2019

We developed a general-purpose multivariate decomposition command for nonlinear response models that incorporates several recent contributions to overcome various problems dealing with path dependence and identification. This work extends existing Stata packages in important ways by including additional models and allowing for weights and model offsets.
Dynamic Simulations of Autoregressive Relationships
Authors: Williams Laron K. , Whitten Guy D.
Published: January 2019

This postestimation technique produces dynamic simulations of autoregressive ordinary least-squares models.
Importing Financial Data
Authors: Dicle Mehmet F. , Levendis John
Published: January 2019

In this article, we describe two commands—fetchyahooquotes and fetchyahookeystats—that import historical financial data and key current financial statistics from Yahoo! Finance.
Reconstructing Time-to-event Data from Published Kaplan–Meier Curves
Authors: Wei Yinghui , Royston Patrick
Published: January 2019

Hazard ratios can be approximated by data extracted from published Kaplan–Meier curves. Recently, this curve approach has been extended beyond hazard-ratio approximation with the capability of constructing time-to-event data at the individual level. In this article, we introduce a command, ipdfc, to implement the reconstruction method to convert Kaplan–Meier curves to time-to-event data. We give examples to illustrate how to use the command.
Text Mining with n-gram Variables
Authors: Schonlau Matthias , Guenther Nick , Sucholutsky Ilia
Published: January 2019

Text mining is the process of turning free text into numerical variables and then analyzing them with statistical techniques. We introduce the command ngram, which implements the most common approach to text mining, the “bag of words”. An n-gram is a contiguous sequence of words in a text. Broadly speaking, ngram creates hundreds or thousands of variables, each recording how often the corresponding n-gram occurs in a given text. This is more useful than it sounds. We illustrate ngram with the categorization of text answers from two open-ended questions.
Two-stage Residual Inclusion Estimation: A Practitioners Guide to Stata Implementation
Authors: Terza Joseph V.
Published: January 2019

Empirical econometric research often requires implementation of nonlinear models whose regressors include one or more endogenous variables—regressors that are correlated with the unobserved random component of the model. In such cases, conventional regression methods that ignore endogeneity will likely produce biased results that are not causally interpretable. Terza, Basu, and Rathouz (2008, Journal of Health Economics 27: 531–543) discuss a relatively simple estimation method (two-stage residual inclusion) that avoids endogeneity bias, is applicable in many nonlinear regression contexts, and can easily be implemented in Stata. In this article, I offer a step-by-step protocol to implement the two-stage residual inclusion method in Stata. I illustrate this protocol in the context of a real-data example. I also discuss other examples and pertinent Stata code.
A Simple Command to Calculate Travel Distance and Travel Time
Authors: Weber Sylvain , Péclat Martin
Published: January 2019

Obtaining the routing distance between two addresses should not be a hassle with current technology. Unfortunately, this is more complicated than it first seems. Recently, several commands have been implemented for this purpose (traveltime, traveltime3, mqtime, osrmtime), but most of them became obsolete only a few months after their introduction or appear complicated to use. In this article, we introduce the community-contributed command georoute, which retrieves travel distance and travel time between two points defined either by their addresses or by their geographical coordinates. Compared with other existing commands, it is simple to use, efficient in terms of computational speed, and versatile regarding the information that can be provided as input.
Response Surface Models for the Elliott, Rothenberg, and Stock Unit-root Test
Authors: Otero Jesús , Baum Christopher F.
Published: January 2019

In this article, we present response surface coefficients for a large range of quantiles of the Elliott, Rothenberg, and Stock (1996, Econometrica 64: 813–836) unit-root tests, for different combinations of number of observations, T, and lag order in the test regressions, p, where the latter can either be specified by the user or be endogenously determined. The critical values depend on the method used to select the number of lags. We present the command ersur and illustrate its use with an empirical example that tests the validity of the expectations hypothesis of the term structure of interest rates.
Assessing the Calibration of Dichotomous Outcome Models with the Calibration Belt
Authors: Nattino Giovanni , Lemeshow Stanley , Phillips Gary , Finazzi Stefano , Bertolini Guido
Published: January 2019

The calibration belt is a graphical approach designed to evaluate the goodness of fit of binary outcome models such as logistic regression models. The calibration belt examines the relationship between estimated probabilities and observed outcome rates. Significant deviations from the perfect calibration can be spotted on the graph. The graphical approach is paired to a statistical test, synthesizing the calibration assessment in a standard hypothesis testing framework. In this article, we present the calibrationbelt command, which implements the calibration belt and its associated test in Stata.
Six-Month Freedom From Amputation Rates and Quality of Life Following Tibial and Pedal Endovascular Revascularization for Critical Limb Ischemia
Authors: Dua Anahita , Rothenberg Kara A. , Lee Jisun J. , Gologorsky Rebecca , Desai Sapan S.
Published: January 2019

Objective:

Patients with critical limb ischemia (CLI) and gangrene have a 10% to 38% rate of major amputation at 6 months. The purpose of this study is to report short- and mid-term major and minor amputation rates for patients who underwent tibial and pedal revascularization in addition to quality-of-life (QoL) scores.

Methods:

All patients who presented to a single institution with CLI (defined as rest pain or nonhealing wounds) and underwent antegrade or retrograde tibial access, atherectomy and angioplasty of the tibial circulation, and angioplasty of pedal circulation (antegrade or retrograde) from June 2016 to September 2017 were included. The Stark QoL questionnaire was used at each visit. Patients were scored at 1, 3, and 6 months postprocedure. Amputation rates were recorded.

Results:

Forty-two patients with CLI and gangrene underwent 57 peripheral interventions for limb salvage between June 2016 and September 2017. Thirty-two limbs had dry gangrene along the dorsalis pedis angiosome, 14 limbs had dry gangrene along the posterior tibial angiogram, and 11 limbs had a combined disease pattern. Twelve limbs underwent angioplasty of the superficial femoral artery (SFA), 18 limbs underwent angioplasty and stenting of the SFA, and 14 limbs underwent atherectomy, angioplasty, and stenting of the SFA. All patients had 1 or 2 tibial vessel runoff and high-grade stenosis of the pedal circulation. Immediate technical success defined as 3-vessel outflow to the foot occurred in 49 limbs (86%) with zero 30-day complications (30-day readmission, major amputation, or sepsis). Major amputation rate at 1, 3, and 6 months was 0%, 2%, and 4%, respectively. Patient satisfaction in terms of QoL increased over the 6-month follow-up period.

Conclusion:

Aggressive tibial and pedal revascularization may improve freedom from minor and major amputation at 6 months and may be associated with a short- and mid-term higher QoL.
A novel weighted evidence combination rule based on improved entropy function with a diagnosis application
Authors: Chen Lei , Diao Ling , Sang Jun
Published: January 2019

Managing conflict in Dempster–Shafer theory is a popular topic. In this article, we propose a novel weighted evidence combination rule based on improved entropy function. This newly proposed approach can be mainly divided into two steps. First, the initial weight will be determined on the basis of the distance of evidence. Then, this initial weight will be modified using improved entropy function. This new method converges faster when handling high conflicting evidences and greatly reduces uncertainty of decisions, which can be demonstrated by a numerical example where the belief degree is raised up to 0.9939 when five evidences are in conflict, an application in faulty diagnosis where belief degree is increased hugely from 0.8899 to 0.9416 when compared with our previous works, and a real-life medical diagnosis application where the uncertainty of decision is reduced to nearly 0 and the belief degree is raised up to 0.9989.
Natural Products Mediated Targeting of Virally Infected Cancer
Authors: Fatima Iram , Kanwal Sobia , Mahmood Tariq
Published: January 2019

The role of viral infection in developing cancer was determined in the start of 20th century. Until now, 8 different virus-associated cancers have been discovered and most of them progressed in immunosuppressed individuals. The aim of the present study is to look into the benefits of natural products in treating virally infected cancers. The study focuses on bioactive compounds derived from natural sources. Numerous pharmaceutical agents have been identified from plants (vincristine, vinblastine, stilbenes, combretastatin, and silymarin), marine organisms (bryostatins, cephalostatin, ecteinascidins, didemnin, and dolastatin), insects (cantharidin, mastoparan, parectadial, and cecropins), and microorganisms (vancomycin, rhizoxin, ansamitocins, mitomycin, and rapamycin). Beside these, various compounds have been observed from fruits and vegetables which can be utilized in anticancer therapy. These include curcumin in turmeric, resveratrol in red grapes, S-allyl cysteine in allium, allicin in garlic, catechins in green tea, and β-carotene in carrots. The present study addresses various types of virally infected cancers, their mechanism of action, and the role of different cell surface molecules elicited during viral binding and entry into the target cell along with the anticancer drugs derived from natural products by targeting screening of bioactive compounds from natural sources.
Analysis of the efficiency of shipping containers handling/loading control methods and procedures
Authors: Eglynas Tomas , Jusis Mindaugas , Jakovlev Sergej , Senulis Audrius , Andziulis Arunas , Gudas Saulius
Published: January 2019

Most modern quay cranes operate under the operator’s control. Lifting, lowering, and transporting a container from one platform to another are just some of the actions that a person is responsible for, but the negative consequences of handling can be caused not only by his actions. An error, loading transient instability, or an undervalued environmental factor in the control algorithm can cause a risk to human safety, container, and cargo security. In order to control cargo-handling risk, it is necessary to improve the cargo control systems not only by changing their software, but also by creating additional control algorithms and systems. These systems with programmed control algorithms should be integrated into existing systems to control cargo security and its transfer time. In this article, transient processes and dynamic property of the cargo-handling operation are described and multibody dynamics simulation performed using laboratory prototype of a quay crane. The experimental research performed and integrated autonomous quay crane control algorithm developed with the proposed embedded container swinging control subroutine operated in optimal mode when the control system used PID controller with a feedback including additional PI controller and S-shaped input signal for the analyzed case with the defined parameter set.
A study on weight-on-bit data correction method of a near-bit measuring tool
Authors: Xu Xiaofeng , Meng Yingfeng , Liu Yonghui , Ji Yueying
Published: January 2019

The real weight on bit is difficult to observe or estimate in highly deviated wells and extended-reach wells since complex loads are acted on drill string. Near-bit measurement while drilling tools, which are generally used to address this issue, can only measure axial forces based on axial strains instead of the real WOB. Axial forces on near-bit drill string are mainly controlled by buoyancy force of drilling fluid, circulating pressure, and other factors. To some extent, the measured data can be corrected by force analysis. It should be noted that experiments must be conducted to study the influences of differential pressure and temperature on measured WOB data of near-bit measuring tool. This article presents calculating method of real WOB via correction of measured data, based on force analysis of a self-developed near-bit measuring tool and experiments on influences of differential pressure and downhole temperature. Field test indicates that higher deviation angle will lead to a greater difference between real WOB and the indicated value at wellhead. Multi-well testing data verification indicates that this method is effective and reliable in extracting real WOB, and helpful to accurately identify the running state of bottom-hole assembly.
Rituximab for the maintenance of minimal change nephropathy – A report of two pregnancies
Authors: Holden Francesca , Bramham Kate , Clark Katherine
Published: January 2019

Rituximab targets the CD20 antigen expressed on B-lymphocytes and is used to treat recurrent minimal change disease, but experience of its use in pregnancy is limited. We describe a 28-year-old Caucasian female, with recurrent nephrotic syndrome secondary to minimal change disease. She had failed to respond to non-teratogenic alternative therapies. The patient was successfully maintained in remission with rituximab during two consecutive pregnancies. Rituximab (1 g) was administered at 14+6 weeks 14 weeks and 6 days during Pregnancy 1 and 500 mg administered at 23+4 weeks 23 weeks and 4 days of Pregnancy 2. Rituximab had no apparent effect on infant B-cell development in either pregnancy, as neonatal lymphocyte titres were within normal range. There were no maternal complications in either pregnancy. Neither infant encountered infection-related complications. Although rituximab administration during pregnancy appeared safe, evidence of placental transfer is reported with neonatal B-cell depletion, thus alternatives with known safety profiles in pregnancy should be considered before rituximab administration.
Experimental validation of lift and drag forces on an asymmetrical hydrofoil for seafloor anchoring applications
Authors: Byrne Gerry , Persoons Tim , Kingston William
Published: January 2019

Tidal power can be described as harnessing the kinetic energy of the in and out flows known as tides created by the changing gravitational pull of the moon and the sun on the oceans of the world. As the relative positions of the sun and moon can be accurately predicted, so can the resultant tidal movements, making tidal energy such a valuable resource and an attractive option for renewable power generation. However, the high costs and difficulties associated with the deployment of underwater turbines, which includes anchoring, are prohibitive factors in the widespread utilisation of tidal power technology. Existing turbine fixation methods are primarily based on the use of large gravity anchors or monopole structures to secure the turbine to the seabed. In an effort to reduce size, environmental impact on the seafloor and installation cost, a hydrofoil-based anchor could be considered. The objective of this study is to experimentally test the lift and drag force behaviour of a finite-span hydrofoil with endplates, whose profile was selected based on simplified two-dimensional (2D) numerical simulations using the vortex panel method. A customised lift and drag force measurement system for this prototype hydrofoil was designed, fabricated and calibrated, and subsequently installed and tested in the Dutch Tidal Testing Centre (TTC) in Den Oever, the Netherlands. A series of tests with force and flow velocity measurements are described for different angles-of-attack under realistic tidal flow conditions. Results for the lift and drag coefficients as a function of angle-of-attack are compared to numerical simulation data and revealed that the real-world lift force is predicted well, whereas the drag force is underpredicted by the numerical predictions. These findings provide useful information for the design of anchoring systems based of hydrofoil profiles.