bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing critical care of the trauma patient at the intermediate care unit: a cost-efficient approach
Authors: Plate Joost D J , Peelen Linda M , Leenen Luke P H , Hietbrink Falco
Published: October 2018

Background

The aim of this study was to describe the case load, safety, and cost savings of critical care of the trauma patient provided at the surgical intermediate care unit (IMCU).

﻿Methods

This cohort study included all trauma admissions between January 1, 2011 and January 7, 2015 at the general intensive care unit (ICU), stand-alone neuro(surgical) IMCU, and stand-alone (trauma) surgical IMCU. Trauma mechanism, Abbreviated Injury Scale score and Injury Severity Score (ISS), vital signs, laboratory parameters, admission duration, intubation duration, ICU transfer, and in-hospital mortality were prospectively collected. Hypothetical cost savings were calculated using the fixed cost price per IMCU (US$1500) and ICU (US$2500) admission day.

Results

A total of 1320 admissions were included, 675 (51.1%) at the IMCU and 645 (48.9%) at the ICU. Patients admitted at the IMCU had a median ISS of 17 (11, 22). Their median duration of admission was 32.8 hours (18.8, 62.5). At the IMCU, one patient died due to aneurogenic shock. A subsequent ICU transfer was required in 38 (5.6%) IMCU admissions. Of these transfers, four patients died due to neurological deterioration. At the ICU, the median ISS was 22 (14, 30). Nearly all (n=620, 96.3%) ICU trauma patients required mechanical ventilation. Expected total cost savings due to the presence of the IMCU were US$1 772 785.

Discussion

A substantial amount of trauma patients in need of critical care can safely be admitted at the IMCU, without the need for further mechanical ventilation. Thereby, the IMCU could fulfill an essential cost-saving role in the management of severely injured trauma patients.

Level of evidence

Level IV.
Reporting of suspected dog fighting to the police, Royal Society for the Prevention of Cruelty to Animals and equivalents by veterinary professionals in the UK
Authors: Milroy Kate Elizabeth , Whiting Martin , Abeyesinghe Siobhan
Published: October 2018

Dog fighting became unlawful in the UK in 1835, yet it continues today (as reported by the Royal Society for the Prevention of Cruelty to Animals (RSPCA) and Crown Prosecution Service), although with an unknown prevalence. We used an online questionnaire to (1) determine the occurrence of dogs suspected of use in fighting in UK veterinary practices; (2) explore relative reporting of incidents to police, RSPCA or equivalent charity by registered veterinary nurses (RVN) and veterinarians; and (3) determine factors influencing reporting. Emails (n=2493) containing the questionnaire were sent to UK veterinary practices: 423 questionnaires (159 by RVNs, 264 by veterinarians) were completed. One or more cases of dog fighting were suspected by 14.4 per cent of respondents in 2015; 182 cases suspected in total. Proportionately more RVNs suspected dog fighting than veterinarians (P=0.0009). Thirty‐two respondents (7.6 per cent, n=422) claimed to have reported suspicions to the police, the RSPCA or equivalent charity previously; 59 respondents (14.2 per cent) had previously chosen not to. Reasons not to report included: uncertainty of illegal activity (81.4 per cent), fear of the client not returning to the practice (35.6 per cent) and concerns regarding client confidentiality (22.0 per cent). Further work is required to address under‐reporting of dog fighting by veterinary professionals.
Pressure effect on the mechanical and electronic properties of orthorhombic-C20
Authors: Ma Jian-Li , Fu Zhi-Fen , Wei Qun , Liu Peng , Zhou Jian-Ping
Published: October 2018

A systematic investigation of structural, mechanical, elastic anisotropy and electronic properties of a recently reported novel superhard material orthorhombic [Formula: see text] ([Formula: see text]-[Formula: see text]) under pressure is performed utilizing the density functional theory in this work. The crystal structure parameters are obtained at zero as well as at high pressure. Pressure induced elastic constants [Formula: see text], polycrystalline aggregate elastic modulus [Formula: see text], [Formula: see text] ratio, and Debye temperature changes for [Formula: see text]-[Formula: see text] have been determined. The crystal elastic anisotropies of the ultra-incompressible [Formula: see text]-[Formula: see text] are investigated in the pressure range of 0–100 GPa. The Lyakhov–Oganov model is applied to predict the hardness as functions of pressure. The calculated results reveal that [Formula: see text]-[Formula: see text] possesses high elastic anisotropy under zero pressure and high pressure, and the hardness of [Formula: see text]-[Formula: see text] decreases with pressure, while the Debye temperature behaves with the opposite trend. The results of electronic structure indicate that [Formula: see text]-[Formula: see text] exhibits insulator characteristics, and the band gap increases with pressure. This work is expected to provide a useful guide for the future synthesis and application of [Formula: see text]-[Formula: see text].
Deconfinement of nonstrange hadronic matter with nucleons and Δ baryons to quark matter in neutron stars
Authors: Sen Debashree , Jha T. K.
Published: October 2018

We explore the possibility of formation of [Formula: see text] baryons (1232[Formula: see text]MeV) in neutron star matter in an effective chiral model within the relativistic mean-field framework. With variation in delta-meson couplings, consistent with the constraints imposed on them, the resulting equation-of-state (EoS) is obtained and the neutron star properties are calculated for static and spherical configuration. Within the framework of our model, the critical densities of formation of [Formula: see text] and the properties of neutron stars (NS) are found to be very sensitive to the iso-vector coupling compared to the scalar or vector couplings. We revisit the [Formula: see text] puzzle and look for the possibility of phase transition from nonstrange hadronic matter (including nucleons and [Formula: see text]) to deconfined quark matter, based on QCD theories. The resultant hybrid star configurations satisfy the observational constraints on mass from the most massive pulsars PSR J1614-2230 and PSR J0348+0432 in static condition obtained with the general hydrostatic equilibrium based on GTR. Our radius estimates are well within the limits imposed from observational analysis of QLMBXs. The obtained values of [Formula: see text] are in agreement with the recent bounds specified from the observation of gravitational wave (GW170817) from binary neutron star merger. The constraint on baryonic mass from the study of binary system PSR J0737-3039 is also satisfied with our hybrid EoS.
Social Media and Regionalism in South Korean Voting Behavior: The Case of the 19th South Korean Presidential Election
Authors: LEE JAE MOOK , PARK YOUNGDEUK , KIM GI DONG
Published: October 2018

This study examines the moderating effects of social media use on regionalist voting behavior in South Korea. Analyzing the survey data conducted during the 2017 Korean presidential election, we test how social media functions in electoral processes, particularly with respect to region-based voting in the Korean electorate. The findings of this study reveal that social media use affects region-based voting behavior among the Korean electorate by connecting people with different regional backgrounds in online political communication. That is, social media use can create “bridging” social capital rather than “bonding” social capital in society. In this respect, results differ significantly from findings in the 2012 presidential election. In 2012, only the independent effects of social media existed with a liberal bias, without revealing interaction with regional dummies. These independent effects disappeared in 2017, and different kinds of social media were statistically significant only when they functioned as moderating variables for regional dummies. This implies that as the functions of social media in the Korean election process have evolved in more complexity, they now are able to affect progressive as well as conservative voters.
Thread-safe reactive programming
Authors: Drechsler Joscha , Mogk Ragnar , Salvaneschi Guido , Mezini Mira
Published: October 2018

The execution of an application written in a reactive language involves transfer of data and control flow between imperative and reactive abstractions at well-defined points. In a multi-threaded environment, multiple such interactions may execute concurrently, potentially causing data races and event ordering ambiguities. Existing RP languages either disable multi-threading or handle it at the cost of reducing expressiveness or weakening consistency. This paper proposes a model for thread-safe reactive programming (RP) that ensures abort-free strict serializability under concurrency while sacrificing neither expressiveness nor consistency. We also propose an architecture for integrating a corresponding scheduler into the RP language runtime, such that thread-safety is provided "out-of-the-box" to the applications.

We show the feasibility of our proposal by providing and evaluating a ready-to-use implementation integrated into the REScala programming language. The scheduling algorithm is formally proven correct. A thorough empirical evaluation shows that reactive applications build on top of it scale with multiple threads, while the scheduler incurs acceptable performance overhead in a single-threaded configuration. The scalability enabled by our scheduler is roughly on-par with that of hand-crafted application-specific locking and better than the scalability enabled by a scheduler using an off-the-shelf software transactional memory library.
Julia subtyping: a rational reconstruction
Authors: Zappa Nardelli Francesco , Belyakova Julia , Pelenitsyn Artem , Chung Benjamin , Bezanson Jeff , Vitek Jan
Published: October 2018

Programming languages that support multiple dispatch rely on an expressive notion of subtyping to specify method applicability. In these languages, type annotations on method declarations are used to select, out of a potentially large set of methods, the one that is most appropriate for a particular tuple of arguments. Julia is a language for scientific computing built around multiple dispatch and an expressive subtyping relation. This paper provides the first formal definition of Julia's subtype relation and motivates its design. We validate our specification empirically with an implementation of our definition that we compare against the existing Julia implementation on a collection of real-world programs. Our subtype implementation differs on 122 subtype tests out of 6,014,476. The first 120 differences are due to a bug in Julia that was fixed once reported; the remaining 2 are under discussion.
Scopes as types
Authors: van Antwerpen Hendrik , Bach Poulsen Casper , Rouvoet Arjen , Visser Eelco
Published: October 2018

Scope graphs are a promising generic framework to model the binding structures of programming languages, bridging formalization and implementation, supporting the definition of type checkers and the automation of type safety proofs. However, previous work on scope graphs has been limited to simple, nominal type systems. In this paper, we show that viewing scopes as types enables us to model the internal structure of types in a range of non-simple type systems (including structural records and generic classes) using the generic representation of scopes. Further, we show that relations between such types can be expressed in terms of generalized scope graph queries. We extend scope graphs with scoped relations and queries. We introduce Statix, a new domain-specific meta-language for the specification of static semantics, based on scope graphs and constraints. We evaluate the scopes as types approach and the Statix design in case studies of the simply-typed lambda calculus with records, System F, and Featherweight Generic Java.
A derivation framework for dependent security label inference
Authors: Li Peixuan , Zhang Danfeng
Published: October 2018

Dependent security labels (security labels that depend on program states) in various forms have been introduced to express rich information flow policies. They are shown to be essential in the verification of real-world software and hardware systems such as conference management systems, Android Apps, a MIPS processor and a TrustZone-like architecture. However, most work assumes that all (complex) labels are provided manually, which can both be error-prone and time-consuming.

In this paper, we tackle the problem of automatic label inference for static information flow analyses with dependent security labels. In particular, we propose the first general framework to facilitate the design and validation (in terms of soundness and/or completeness) of inference algorithms. The framework models label inference as constraint solving and offers guidelines for sound and/or complete constraint solving. Under the framework, we propose novel constraint solving algorithms that are both sound and complete. Evaluation result on sets of constraints generated from secure and insecure variants of a MIPS processor suggests that the novel algorithms improve the performance of an existing algorithm by orders of magnitude and offers better scalability.
Faster variational execution with transparent bytecode transformation
Authors: Wong Chu-Pan , Meinicke Jens , Lazarek Lukas , Kästner Christian
Published: October 2018

Variational execution is a novel dynamic analysis technique for exploring highly configurable systems and accurately tracking information flow. It is able to efficiently analyze many configurations by aggressively sharing redundancies of program executions. The idea of variational execution has been demonstrated to be effective in exploring variations in the program, especially when the configuration space grows out of control. Existing implementations of variational execution often require heavy lifting of the runtime interpreter, which is painstaking and error-prone. Furthermore, the performance of this approach is suboptimal. For example, the state-of-the-art variational execution interpreter for Java, VarexJ, slows down executions by 100 to 800 times over a single execution for small to medium size Java programs. Instead of modifying existing JVMs, we propose to transform existing bytecode to make it variational, so it can be executed on an unmodified commodity JVM. Our evaluation shows a dramatic improvement on performance over the state-of-the-art, with a speedup of 2 to 46 times, and high efficiency in sharing computations.
An empirical study of the effect of source-level loop transformations on compiler stability
Authors: Gong Zhangxiaowen , Chen Zhi , Szaday Justin , Wong David , Sura Zehra , Watkinson Neftali , Maleki Saeed , Padua David , Veidenbaum Alexander , Nicolau Alexandru , Torrellas Josep
Published: October 2018

Modern compiler optimization is a complex process that offers no guarantees to deliver the fastest, most efficient target code. For this reason, compilers struggle to produce a stable performance from versions of code that carry out the same computation and only differ in the order of operations. This instability makes compilers much less effective program optimization tools and often forces programmers to carry out a brute force search when tuning for performance. In this paper, we analyze the stability of the compilation process and the performance headroom of three widely used general purpose compilers: GCC, ICC, and Clang. For the study, we extracted over 1,000 for loop nests from well-known benchmarks, libraries, and real applications; then, we applied sequences of source-level loop transformations to these loop nests to create numerous semantically equivalent
mutations
; finally, we analyzed the impact of transformations on code quality in terms of locality, dynamic instruction count, and vectorization. Our results show that, by applying source-to-source transformations and searching for the best vectorization setting, the percentage of loops sped up by at least 1.15x is 46.7% for GCC, 35.7% for ICC, and 46.5% for Clang, and on average the potential for performance improvement is estimated to be at least 23.7% for GCC, 18.1% for ICC, and 26.4% for Clang. Our stability analysis shows that, under our experimental setup, the average coefficient of variation of the execution time across all mutations is 18.2% for GCC, 19.5% for ICC, and 16.9% for Clang, and the highest coefficient of variation for a single loop nest reaches 118.9% for GCC, 124.3% for ICC, and 110.5% for Clang. We conclude that the evaluated compilers need further improvements to claim they have stable behavior.
Distributed system development with ScalaLoci
Authors: Weisenburger Pascal , Köhler Mirko , Salvaneschi Guido
Published: October 2018

Distributed applications are traditionally developed as separate modules, often in different languages, which react to events, like user input, and in turn produce new events for the other modules. Separation into components requires time-consuming integration. Manual implementation of communication forces programmers to deal with low-level details. The combination of the two results in obscure distributed data flows scattered among multiple modules, hindering reasoning about the system as a whole.

The ScalaLoci distributed programming language addresses these issues with a coherent model based on placement types that enables reasoning about distributed data flows, supporting multiple software architectures via dedicated language features and abstracting over low-level communication details and data conversions. As we show, ScalaLoci simplifies developing distributed systems, reduces error-prone communication code and favors early detection of bugs.
Collapsible contracts: fixing a pathology of gradual typing
Authors: Feltey Daniel , Greenman Ben , Scholliers Christophe , Findler Robert Bruce , St-Amour Vincent
Published: October 2018

The promise of gradual typing is that programmers should get the best of both worlds: the static guarantees of static types, and the dynamic flexibility of untyped programming. This is an enticing benefit, but one that, in practice, may carry significant costs. Significant enough, in fact, to threaten the very practicality of gradual typing; slowdowns as high as 120x are reported as arising from gradual typing.

If one examines these results closely, though, it becomes clear that the costs of gradual typing are not evenly distributed. Indeed, while mixing typed and untyped code almost invariably carries non-trivial costs, many truly deal-breaking slowdowns exhibit pathological performance. Unfortunately, the very presence of these pathological cases---and therefore the possibility of hitting them during development---makes gradual typing a risky proposition in any setting that even remotely cares about performance.

This work attacks one source of large overheads in these pathological cases: an accumulation of contract wrappers that perform redundant checks. The work introduces a novel strategy for contract checking---collapsible contracts---which eliminates this redundancy for function and vector contracts and drastically reduces the overhead of contract wrappers.

We implemented this checking strategy as part of the Racket contract system, which is used in the Typed Racket gradual typing system. Our experiments show that our strategy successfully brings a class of pathological cases in line with normal cases, while not introducing an undue overhead to any of the other cases. Our results also show that the performance of gradual typing in Racket remains prohibitive for many programs, but that collapsible contracts are one essential ingredient in reducing the cost of gradual typing.
The root cause of blame: contracts for intersection and union types
Authors: Williams Jack , Morris J. Garrett , Wadler Philip
Published: October 2018

Gradual typing has emerged as the tonic for programmers with a thirst for a blend of static and dynamic typing. Contracts provide a lightweight form of gradual typing as they can be implemented as a library, rather than requiring a gradual type system.

Intersection and union types are well suited to static and dynamic languages: intersection encodes overloaded functions; union encodes uncertain data arising from branching code. We extend the untyped lambda calculus with contracts for monitoring higher-order intersection and union types, for the first time giving a uniform treatment to both. Each operator requires a single reduction rule that does not depend on the constituent types or the context of the operator.

We present a new method for defining contract satisfaction based on blame behaviour. A value positively satisfies a type if applying a contract of that type can never elicit positive blame. A continuation negatively satisfies a type if applying a contract of that type can never elicit negative blame. We supplement our definition of satisfaction with a series of monitoring properties that satisfying values and continuations should have.
Identifying refactoring opportunities for replacing type code with subclass and state
Authors: Vedurada Jyothi , Nandivada V. Krishna
Published: October 2018

Refactoring is a program transformation that restructures existing code without altering its behaviour and is a key practice in popular software design movements, such as Agile. Identification of potential refactoring opportunities is an important step in the refactoring process. In large systems, manual identification of useful refactoring opportunities requires a lot of effort and time. Hence, there is a need for automatic identification of refactoring opportunities. However, this problem has not been addressed well for many non-trivial refactorings. Two such non-trivial, yet popular refactorings are “Replace Type Code with Subclass” (SC) and “Replace Type Code with State” (ST) refactorings. In this paper, we present new approaches to identify SC and ST refactoring opportunities.

Our proposed approach is based around the notion of
control-fields
. A control-field is a field of a class that exposes the different underlying behaviors of the class. Each control-field can lead to a possible SC/ST refactoring of the associated/interacting classes. We first present a formal definition of control-fields and then present algorithms to identify and prune them; each of these pruned control-fields represents a refactoring opportunity. Further, we present a novel flow- and context-sensitive analysis to classify each of these refactoring opportunities into one of the SC and ST opportunities. We have implemented our proposed approach in a tool called Auto-SCST, and demonstrated its effectiveness by evaluating it against eight open-source Java applications.
Every data structure deserves lock-free memory reclamation
Authors: Cohen Nachshon
Published: October 2018

Memory-management support for lock-free data structures is well known to be a tough problem. Recent work has successfully reduced the overhead of such schemes. However, applying memory-management support to a data structure remains complex and, in many cases, requires redesigning the data structure. In this paper, we present the first lock-free memory-management scheme that is applicable to general (arbitrary) lock-free data structures and that can be applied automatically via a compiler plug-in. In addition to the simplicity of incorporating to data structures, this scheme provides low overhead and does not rely on the lock freedom of any OS services.
RacerD: compositional static race detection
Authors: Blackshear Sam , Gorogiannis Nikos , O'Hearn Peter W. , Sergey Ilya
Published: October 2018

Automatic static detection of data races is one of the most basic problems in reasoning about concurrency. We present RacerD—a static program analysis for detecting data races in Java programs which is fast, can scale to large code, and has proven effective in an industrial software engineering scenario. To our knowledge, RacerD is the first inter-procedural, compositional data race detector which has been shown to have non-trivial precision and impact. Due to its compositionality, it can analyze code changes quickly, and this allows it to perform continuous reasoning about a large, rapidly changing codebase as part of deployment within a continuous integration ecosystem. In contrast to previous static race detectors, its design favors reporting high-confidence bugs over ensuring their absence. RacerD has been in deployment for over a year at Facebook, where it has flagged over 2500 issues that have been fixed by developers before reaching production. It has been important in enabling the development of new code as well as fixing old code: it helped support conversion of part of the main Facebook Android app from a single-threaded to a multi-threaded architecture. In this paper we describe RacerD’s design, implementation, deployment and impact.
Reactive caching for composed services: polling at the speed of push
Authors: Burckhardt Sebastian , Coppieters Tim
Published: October 2018

Sometimes, service clients repeat requests in a polling loop in order to refresh their view. However, such polling may be slow to pick up changes, or may increase the load unacceptably, in particular for composed services that disperse over many components. We present an alternative
reactive polling
API and
reactive caching
algorithm that combines the conceptual simplicity of polling with the efficiency of push-based change propagation. A reactive cache contains a summary of a distributed read-only operation and maintains a connection to its dependencies so changes can be propagated automatically.

We first formalize the setting using an abstract calculus for composed services. Then we present a fault-tolerant distributed algorithm for reactive caching that guarantees eventual consistency. Finally, we implement and evaluate our solution by extending the Orleans actor framework, and perform experiments on two benchmarks in a distributed cloud deployment. The results show that our solution provides superior performance compared to polling, at a latency that comes close to hand-written change notifications.
Relational program synthesis
Authors: Wang Yuepeng , Wang Xinyu , Dillig Isil
Published: October 2018

This paper proposes relational program synthesis, a new problem that concerns synthesizing one or more programs that collectively satisfy a relational specification. As a dual of relational program verification, relational program synthesis is an important problem that has many practical applications, such as automated program inversion and automatic generation of comparators. However, this relational synthesis problem introduces new challenges over its non-relational counterpart due to the combinatorially larger search space. As a first step towards solving this problem, this paper presents a synthesis technique that combines the counterexample-guided inductive synthesis framework with a novel inductive synthesis algorithm that is based on relational version space learning. We have implemented the proposed technique in a framework called Relish, which can be instantiated to different application domains by providing a suitable domain-specific language and the relevant relational specification. We have used the Relish framework to build relational synthesizers to automatically generate string encoders/decoders as well as comparators, and we evaluate our tool on several benchmarks taken from prior work and online forums. Our experimental results show that the proposed technique can solve almost all of these benchmarks and that it significantly outperforms EUSolver, a generic synthesis framework that won the general track of the most recent SyGuS competition.
Randomized testing of distributed systems with probabilistic guarantees
Authors: Ozkan Burcu Kulahcioglu , Majumdar Rupak , Niksic Filip , Befrouei Mitra Tabaei , Weissenbacher Georg
Published: October 2018

Several recently proposed randomized testing tools for concurrent and distributed systems come with theoretical guarantees on their success. The key to these guarantees is a notion of bug depth—the minimum length of a sequence of events sufficient to expose the bug—and a characterization of
d
-hitting families of schedules—a set of schedules guaranteed to cover every bug of given depth
d
. Previous results show that in certain cases the size of a
d
-hitting family can be significantly smaller than the total number of possible schedules. However, these results either assume shared-memory multithreading, or that the underlying partial ordering of events is known statically and has special structure. These assumptions are not met by distributed message-passing applications.

In this paper, we present a randomized scheduling algorithm for testing distributed systems. In contrast to previous approaches, our algorithm works for arbitrary partially ordered sets of events revealed online as the program is being executed. We show that for partial orders of width at most
w
and size at most
n
(both statically unknown), our algorithm is guaranteed to sample from at most
w
2
n

d
−1

schedules, for every fixed bug depth
d
. Thus, our algorithm discovers a bug of depth
d
with probability at least 1 / (
w
2
n

d
−1

). As a special case, our algorithm recovers a previous randomized testing algorithm for multithreaded programs. Our algorithm is simple to implement, but the correctness arguments depend on difficult combinatorial results about online dimension and online chain partitioning of partially ordered sets.

We have implemented our algorithm in a randomized testing tool for distributed message-passing programs. We show that our algorithm can find bugs in distributed systems such as Zookeeper and Cassandra, and empirically outperforms naive random exploration while providing theoretical guarantees.
Verified three-way program merge
Authors: Sousa Marcelo , Dillig Isil , Lahiri Shuvendu K.
Published: October 2018

Even though many programmers rely on 3-way merge tools to integrate changes from different branches, such tools can introduce subtle bugs in the integration process. This paper aims to mitigate this problem by defining a semantic notion of conflict-freedom, which ensures that the merged program does not introduce new unwanted behaviors. We also show how to verify this property using a novel, compositional algorithm that combines lightweight summarization for shared program fragments with precise relational reasoning for the modifications. Towards this goal, our method uses a 4-way differencing algorithm on abstract syntax trees to represent different program versions as edits applied to a shared program with holes. This representation allows our verification algorithm to reason about different edits in isolation and compose them to obtain an overall proof of conflict freedom. We have implemented the proposed technique in a new tool called SafeMerge for Java and evaluate it on 52 real-world merge scenarios obtained from Github. The experimental results demonstrate the benefits of our approach over syntactic conflict-freedom and indicate that SafeMerge is both precise and practical.
Fasting-Evoked En Route Hypoglycemia in Diabetes (FEEHD): An Overlooked Form of Hypoglycemia in Clinical Practice
Authors: Aldasouqi Saleh , Mora Samia , Bhalla Gaurav , Kakumanu Naveen , Corser William , Abela George , Dlewati Mohammad , Estrada Kathleen , Almounajed Abdul , Tabbaa Tarek , Hammoud Jamal , Newkirk Cathy
Published: October 2018

Objective. Many patients with diabetes opt to fast for lab tests, especially for lipid profiles, thus missing breakfast. In parallel, recent studies and international guidelines have indicated that routine fasting for lipid panels may not be necessary. Missing breakfast while fasting for lab tests may invoke hypoglycemia, if patients are not properly instructed about adjusting diabetes medications on the night before or on the day of the lab test. Our group described this form of hypoglycemia and introduced the term FEEHD to refer to it (fasting-evoked en route hypoglycemia in diabetes). In a recently published small study, we reported a rate of occurrence of FEEHD of 27.1%. The objective of this study was to evaluate the rate of occurrence of FEEHD in another clinic. Methods. Patients with diabetes were asked to complete a simple, 2-page survey inquiring about hypoglycemic events while fasting for labs in the preceding 12 months. Results. A total of 525 patients completed the surveys out of 572 patients invited (91.8% response rate). A total of 363 patients with complete data were analyzed, with a mean age of 60.6 (SD 12.5) years. A total of 62 (17.1%) patients reported having experienced one or more FEEHD events in the prior 12 months. Of the 269 patients who were at higher risk of FEEHD (on insulin secretagogues or on insulin), 59 (21.9%) reported having experienced FEEHD. Only 33 of FEEHD patients (53%) recalled having contacted their provider regarding the events and only 22 (35%) indicated having received some sort of FEEHD prevention instructions. Conclusion. Our study shows a significant rate of occurrence of FEEHD in the real world (a clinical practice). FEEHD is especially dangerous, as patients often commute (drive) to and from the laboratory facility (potential risk of traffic accidents). Given study limitations, further studies are needed to assess prevalence of FEEHD in other settings and in the general populations.
The Effect of Reynolds Number on Jet in Asymmetric Co-Flows: A CFD Study
Authors: Teng Ziyan , Larsson I. A. Sofia , Lundström T. Staffan , Marjavaara B. Daniel
Published: October 2018

In rotary kilns in grate-kiln systems for iron ore pelletizing, a long and stable jet flame is needed to ensure a high quality of the pellets. The primary jet issuing from the nozzle interacts with two asymmetric co-flows creating a very complex flow. In order to better understand and eventually model this flow with quality and trust, simplified cases need to be studied. In this work, a simplified and virtual model is built based on a down-scaled kiln model established in a previous experimental work. The aim is to numerically study the jet development as a function of position and Reynolds number (Re). The numerical simulations are carried out with the standardk-εmodel, and quite accurate velocity profiles are obtained while the centerline decays and spreading of the passive scalars are over predicted. The model is capable of predicting a Re dependency of the jet development. With increasing Re, the jet is longer while it generally decays and spreads faster resulting from the stronger shear between the jet and co-flows and the stronger entrainment from the recirculation zone. This recirculation found in the simulations restrain the momentum spreading in the spanwise direction, leading to a slower velocity spreading with higher Re. For further validation and understanding, more measurements in the shear layer and simulations with more advanced turbulence models are necessary.
Long‐Term Administration of Angiotensin (1–7) to db/db Mice Reduces Oxidative Stress Damage in the Kidneys and Prevents Renal Dysfunction
Authors: Papinska Anna Malgorzata , Rodgers Kathleen Elizabeth
Published: October 2018

Aims. The goal of this study was to evaluate the effects of long‐term (16 weeks) administration of angiotensin (1–7) [A(1–7)] on kidney function in db/db mice and to identify the protective mechanisms of this therapy. Methods. db/db mice and heterozygous controls were treated with A(1–7) or vehicle daily, subcutaneously for up to 16 weeks. Kidney injury was assessed by measuring blood flow in renal arteries, plasma creatinine levels, and proteinuria. Effects of treatment on oxidative stress were evaluated by histological staining and gene expression. Results. 16 weeks of daily administration of A(1–7) to a mouse model of severe type 2 diabetes (db/db) prevented the progression of kidney damage. Treatment with A(1–7) improved blood flow in the renal arteries, as well as decreased plasma creatinine levels and proteinuria in diabetic mice. Reduction of oxidative stress was identified as one of the mechanisms of the renoprotective action of A(1–7). Treatment prevented formation of nitrotyrosine residues, a marker of oxidative stress damage. A(1–7) also reduced the expression of two enzymes involved in formation of nitrotyrosine, namely, eNOS and NOX‐4. A(1–7) regulated the phosphorylation pattern of eNOS to enhance production of NO in diabetic animals, possibly through the Akt pathway. However, these elevated levels of NO did not result in increased nitrosylation, possibly due to reduced NOX‐4 levels. Conclusions. Long‐term administration of A(1–7) improved kidney function and reduced oxidative stress damage in db/db mice.
Spectral Characteristics of Acoustic Emission in Carbon Fiber‐Reinforced Composite Materials Subjected to Cyclic Loading
Authors: Shkuratnik Vladimir L. , Nikolenko Petr V.
Published: October 2018

The article is devoted to the investigation of the spectral characteristics of acoustic emission signals that appear under various schemes of composite materials loading. The tests involved samples of composites reinforced with layers sheets of carbon fiber fabric and dispersed carbon fibers. Based on the results of laboratory tests, a comparison is made between the traditional parameters of acoustic emission and the complete spectrograms of the acoustic emission response developed with the use of a special algorithm. The relationship between the emission activity and the change in the spectral composition of emission hits is shown. For example, for some composites, the acoustic emission memory effect (Kaiser effect) manifests itself not only in the time domain but also in the spectral domain in a form of a sharp change in the amplitudes in the frequency range 130/150 kHz. Also, when the samples were loaded according to the Brazilian scheme, the presence of the so‐called “inverse” Kaiser effect is observed, in which the memory carrier “remembers” the previously experienced level of tensile stresses and reproduces this information during subsequent unloading. Such effect manifests itself in the form of a sharp change in the amplitudes in the low‐frequency region of the spectrum.
Evolution of Electoral Preferences for a Regime of Three Political Parties
Authors: Medina Guevara María Guadalupe , Vargas Rodríguez Héctor , Espinoza Padilla Pedro Basilio , Gozález Solís José Luis
Published: October 2018

In this article, we use a discrete system to study the opinion dynamics regarding the electoral preferences of a nontendentious group of agents. To measure the level of preference, a continuous opinion space is used, in which the preference (opinion) can evolve from any political option, to any other; for a regime of three parties, a circle is the convenient space. To model a nonbiased society, new agents are considered. Besides their opinion, they have a new attribute: an individual iterative monoparametric map that imitates a process of internal reflection, allowing them to update their opinion in their own way. These iterative maps introduce six fixed points on the opinion space; the points’ stability depends on the sign of the parameter. When the latter is positive, three attractors are identified with political options, while the repulsors are identified with the antioptions (preferences diametrically opposed to each political choice). In this new model, pairs of agents interact only if their respective opinions are alike; a positive number called confidence bound is introduced with this purpose; if opinions are similar, they update their opinion considering each other’s opinion, while if they are not alike, each agent updates her opinion considering only her individual map. In addition, agents give a certain level of trust (weight) to other agent’s opinions; this results in a positive stochastic matrix of weights which models the social network. The model can be reduced to a pair of coupled nonlinear difference equations, making extracting analytical results possible: a theorem on the conditions governing the existence of consensus in this new artificial society. Some numerical simulations are provided, exemplifying the analytical results.
Marine-Lenhart Syndrome: Case Report, Diagnosis, and Management
Authors: Neuman Danielle , Kuker Russ , Vendrame Francesco
Published: October 2018

The coexistence of thyroid functioning nodules and Graves’ disease is called Marine-Lenhart syndrome. This condition is estimated to occur in 0.8-2.7% of patients with Graves’ disease with few cases reported in the literature. Criteria for the diagnosis are not well defined. Here, we present a case of hyperthyroidism characterized by the presence of stimulating TSH receptor antibodies and severe bilateral exophthalmos. A thyroid uptake and scan revealed an elevated 24-hour iodine-131 uptake and a discrete hot nodule in the upper pole of the right lobe which was also observed with a thyroid ultrasound. The patient was diagnosed with Marine-Lenhart syndrome complicated by thyroid eye disease and was treated with methimazole followed by thyroidectomy and orbital decompression. We review the existing literature and propose criteria for the diagnosis and treatment of this condition.
A Case of Complete Remission from Advanced Gastric Adenocarcinoma with Synchronous Liver Metastasis in Response to EOX Chemotherapy
Authors: Yan Zhi-jun , Wang Jia-xin , Liu You-yi , Li Zhen-hui , Zhang Li-juan , Gan Ping , Han Xiao , Luan Li-kun , Dai You-guo
Published: October 2018

Gastric cancer is a malignant tumor with a high degree of malignancy. Multiple liver metastases from gastric cancer (LMGCs) are common. However, the treatment of LMGCs is very difficult. It is rare to achieve complete remission (CR) and long-term survival after treatment. We present the case of a patient with gastric adenocarcinoma and multiple liver metastases who showed CR for more than 33 months after perioperative EOX (epirubicin, oxaliplatin, and capecitabine) combination chemotherapy with radical distal gastrectomy and resection of liver metastases. The patient is still in follow-up without tumor recurrence. These findings suggest that LMGC does not necessarily mean a poor prognosis; preoperative chemotherapy combined with surgery may be a good treatment option for LMGC in selected patients. Further studies are needed to support this treatment approach.
Roles of Clustering Coefficient for the Network Reconstruction
Authors: Han Jingti , Mao Changmei
Published: October 2018

It is important to establish relations between the network reconstruction and the topological dynamical structure of networks. In this article, we quantify the effect for two types of network topologies on the performance of network reconstruction. First, we generate two network modes with variable clustering coefficient based on Holme-Kim model and Newman-Watts small-world model, then we reconstruct the artificial networks by using a novel framework calledL1-norm minimization algorithm based on a theory called compressive sensing (CS), a framework for recovering sparse signals. The results of the simulation experiment show that the accuracy rate for the network reconstruction is a monotonically increasing function of the clustering coefficient in Holme-Kim model, whereas the opposite occurs in Newman-Watts small-world network. And this yet demonstrates that the larger the network size, the higher the accuracy rate. Morever, we compare the results of CS with orthogonal matching pursuit (OMP), a greedy algorithm. The results show that the accuracy rate ofL1-norm minimization method is 10% higher than that of OMP, and OMP yields 1.2 times the computation speed ofL1-norm minimization. Our work demonstrates that the topological structure of network has influence on the accurate reconstruction and it is helpful for offering proper method for the network reconstruction.
Interest Rate Swap Market Complexity and Its Risk Management Implications
Authors: Yang Steve Y. , Onur Esen
Published: October 2018

The primary objective of this paper is to study the post Dodd‐Frank network structure of the interest rate swap market and propose a set of effective complexity measures to understand how the swap users respond to market risks. We use a unique swap dataset extracted from the swap data repositories (SDRs) to examine the network structure properties and market participants’ risk management behaviors. We find (a) the interest rate swap market follows a scale‐free network where the power‐law exponent is less than 2, which indicates that few of its important entities have a significant number of contracts within their subsidiaries (a.k.a. interaffiliated swap contracts); (b) swap rate volatility Granger‐causes swap users to increase their risk sharing intensity at entity level, but market participants do not change their risk management strategies in general; (c) there is a significant contemporaneous correlation between the swap rate volatility and the underlying interest rate futures volatility. However, interest rate swap volatility does not cause the underlying interest rate futures volatility and vice versa. These findings provide the market regulators and swap users a better understanding of interest rate swap market participants’ risk management behaviors, and it also provides a method to monitor the swap market risk sharing dynamics.
Undrained Dynamic Behavior of Reinforced Subgrade under Long‐Term Cyclic Loading
Authors: Geng Min , Wang Debin , Li Peiyong
Published: October 2018

To study the dynamic behavior of reinforced subgrade, a series of undrained cyclic triaxial tests of reinforced soil (the specimen a height of 50 cm and a diameter of 20 cm) were performed in this paper. The specimens were tested by varying confining pressure, vibration frequency, dynamic stress amplitudes, and reinforced layers. Orthogonal experiment is a better way to optimize the process of experiment. Impact on dynamic behavior of the reinforced soil specimens is discussed through orthogonal design of experiments in four factors and three levels. This study has demonstrated that the order of dynamic elastic modulus of reinforced soil is influenced by dynamic stress amplitude, frequency, reinforced layer, and confining pressure within changing in factor level. The dynamic stress amplitude has great influence on the dynamic elastic modulus of reinforced soil. The bearing capacity and dynamic elastic modulus of reinforced subgrade decrease slightly with the increase of dynamic strain. Frequency has an influence on the dynamic elastic modulus. It is shown that the cumulative strain of reinforced soil is related to the vibration frequency. The test results also exemplify the reinforced subgrade restrict lateral displacement of subgrade and reduce settlement of subgrade under long‐term cyclic loading.
A Flexible Lower Extremity Exoskeleton Robot with Deep Locomotion Mode Identification
Authors: Wang Can , Wu Xinyu , Ma Yue , Wu Guizhong , Luo Yuhao
Published: October 2018

This paper presents a bioinspired lower extremity exoskeleton robot. The proposed exoskeleton robot can be adjusted in structure to meet the wearer’s height of 150–185 cm and has a good gait stability. In the gait control part, a method of identifying different locomotion modes is proposed; five common locomotion modes are considered in this paper, including sitting down, standing up, level‐ground walking, ascending stairs, and descending stairs. The identification is depended on angle information of the hip, knee, and ankle joints. A deep locomotion mode identification model (DLMIM) based on long‐short term memory (LSTM) architecture is proposed in this paper for exploiting the angle data. We conducted two experiments to verify the effectiveness of the proposed method. Experimental results show that the DLMIM is capable of learning inherent characteristics of joint angles and achieves more accurate identification than the other models. The last experiment demonstrates that the DLMIM can recognize transitions between different locomotion modes in time and the real‐time performance varies with each individual.