bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferric Uptake Regulator Fur Is Conditionally Essential in Pseudomonas aeruginosa
Authors: Pasqua Martina , Visaggio Daniela , Lo Sciuto Alessandra , Genah Shirley , Banin Ehud , Visca Paolo , Imperi Francesco
Published: August 2017

In
Pseudomonas aeruginosa
, the ferric uptake regulator (Fur) protein controls both metabolism and virulence in response to iron availability. Differently from other bacteria, attempts to obtain
fur
deletion mutants of
P. aeruginosa
failed, leading to the assumption that Fur is an essential protein in this bacterium. By investigating a
P. aeruginosa
conditional
fur
mutant, we demonstrate that Fur is not essential for
P. aeruginosa
growth in liquid media, biofilm formation, and pathogenicity in an insect model of infection. Conversely, Fur is essential for growth on solid media since Fur-depleted cells are severely impaired in colony formation. Transposon-mediated random mutagenesis experiments identified pyochelin siderophore biosynthesis as a major cause of the colony growth defect of the conditional
fur
mutant, and deletion mutagenesis confirmed this evidence. Impaired colony growth of pyochelin-proficient Fur-depleted cells does not depend on oxidative stress, since Fur-depleted cells do not accumulate higher levels of reactive oxygen species (ROS) and are not rescued by antioxidant agents or overexpression of ROS-detoxifying enzymes. Ectopic expression of
pch
genes revealed that pyochelin production has no inhibitory effects on a
fur
deletion mutant of
Pseudomonas syringae
pv.
tabaci
, suggesting that the toxicity of the
pch
locus in Fur-depleted cells involves a
P. aeruginosa
-specific pathway(s).

IMPORTANCE
Members of the ferric uptake regulator (Fur) protein family are bacterial transcriptional repressors that control iron uptake and storage in response to iron availability, thereby playing a crucial role in the maintenance of iron homeostasis. While
fur
null mutants of many bacteria have been obtained, Fur appears to be essential in
Pseudomonas aeruginosa
for still unknown reasons. We obtained Fur-depleted
P. aeruginosa
cells by conditional mutagenesis and showed that Fur is dispensable for planktonic growth, while it is required for colony formation. This is because Fur protects
P. aeruginosa
colonies from toxicity exerted by the pyochelin siderophore. This work provides a functional basis to the essentiality of Fur in
P. aeruginosa
and highlights unique properties of the Fur regulon in this species.
Academic performance of children born preterm: a meta-analysis and meta-regression
Authors: Twilhaar E Sabrina , de Kieviet Jorrit F , Aarnoudse-Moens Cornelieke SH , van Elburg Ruurd M , Oosterlaan Jaap
Published: August 2017

Background

Advances in neonatal healthcare have resulted in decreased mortality after preterm birth but have not led to parallel decreases in morbidity. Academic performance provides insight in the outcomes and specific difficulties and needs of preterm children.

Objective

To study academic performance in preterm children born in the antenatal steroids and surfactant era and possible moderating effects of perinatal and demographic factors.

Design

PubMed, Web of Science and PsycINFO were searched for peer-reviewed articles. Cohort studies with a full-term control group reporting standardised academic performance scores of preterm children (<37 weeks of gestation) at age 5 years or older and born in the antenatal steroids and surfactant era were included. Academic test scores and special educational needs of preterm and full-term children were analysed using random effects meta-analysis. Random effects meta-regressions were performed to explore the predictive role of perinatal and demographic factors for between-study variance in effect sizes.

Results

The 17 eligible studies included 2390 preterm children and 1549 controls. Preterm children scored 0.71 SD below full-term peers on arithmetic (p<0.001), 0.44 and 0.52 SD lower on reading and spelling (p<0.001) and were 2.85 times more likely to receive special educational assistance (95% CI 2.12 to 3.84, p<0.001). Bronchopulmonarydysplasia explained 44% of the variance in academic performance (p=0.006).

Conclusion

Preterm children born in the antenatal steroids and surfactant era show considerable academic difficulties. Preterm children with bronchopulmonarydysplasia are at particular risk for poor academic outcome.
DisseminatedPseudomonas aeruginosasepsis as presenting diagnosis of X-linked agammaglobulinaemia in a previously well 16-month-old child
Authors: Bhardwaj Naveen Kumar , Khera Daisy , Gupta Neeraj , Singh Kuldeep
Published: August 2017

We report a previously healthy 16-month-old child who presented to us with membranous pharyngitis and ecthyma gangrenosum. In this patient,Pseudomonas aeruginosawas isolated from throat swab, cerebrospinal fluid, skin swab, urine, blood and synovial fluid in a single admission. In further workup, this child was diagnosed as a case of X-linked agammaglobulinaemia. The child was treated successfully with antipseudomonal antibiotics for 6 weeks and intravenous immunoglobulin.
Bacterial and fungal infections in acute-on-chronic liver failure: prevalence, characteristics and impact on prognosis
Authors: Fernández Javier , Acevedo Juan , Wiest Reiner , Gustot Thierry , Amoros Alex , Deulofeu Carme , Reverter Enric , Martínez Javier , Saliba Faouzi , Jalan Rajiv , Welzel Tania , Pavesi Marco , Hernández-Tejero María , Ginès Pere , Arroyo Vicente
Published: August 2017

Bacterial infection is a frequent trigger of acute-on-chronic liver failure (ACLF), syndrome that could also increase the risk of infection. This investigation evaluated prevalence and characteristics of bacterial and fungal infections causing and complicating ACLF, predictors of follow-up bacterial infections and impact of bacterial infections on survival.

Patients

407 patients with ACLF and 235 patients with acute decompensation (AD).

Results

152 patients (37%) presented bacterial infections at ACLF diagnosis; 46%(n=117) of the remaining 255 patients with ACLF developed bacterial infections during follow-up (4 weeks). The corresponding figures in patients with AD were 25% and 18% (p<0.001). Severe infections (spontaneous bacterial peritonitis, pneumonia, severe sepsis/shock, nosocomial infections and infections caused by multiresistant organisms) were more prevalent in patients with ACLF. Patients with ACLF and bacterial infections (either at diagnosis or during follow-up) showed higher grade of systemic inflammation at diagnosis of the syndrome, worse clinical course (ACLF 2-3 at final assessment: 47% vs 26%; p<0.001) and lower 90-day probability of survival (49% vs 72.5%;p<0.001) than patients with ACLF without infection. Bacterial infections were independently associated with mortality in patients with ACLF-1 and ACLF-2. Fungal infections developed in 9 patients with ACLF (2%) and in none with AD, occurred mainly after ACLF diagnosis (78%) and had high 90-day mortality (71%).

Conclusion

Bacterial infections are extremely frequent in ACLF. They are severe and associated with intense systemic inflammation, poor clinical course and high mortality. Patients with ACLF are highly predisposed to develop bacterial infections within a short follow-up period and could benefit from prophylactic strategies.
Factors associated with coronary artery disease and stroke in adults with congenital heart disease
Authors: Bokma Jouke P , Zegstroo Ineke , Kuijpers Joey M , Konings Thelma C , van Kimmenade Roland R J , van Melle Joost P , Kiès Philippine , Mulder Barbara J M , Bouma Berto J
Published: August 2017

Objective

To determine factors associated with coronary artery disease (CAD) and ischaemic stroke in ageing adult congenital heart disease (ACHD) patients.

Methods

We performed a multicentre case–control study, using data from the national CONgenital CORvitia (CONCOR) registry to identify ACHD patients within five participating centres. Patients with CAD were matched (1:2 ratio) with ACHD patients without CAD on age, CHD defect group and gender. Patients with ischaemic stroke (or transient ischaemic attack) were matched similarly. Medical charts were reviewed and a standardised questionnaire was used to determine presence of risk factors.

Results

Of 6904 ACHD patients, a total of 55 cases with CAD (80% male, mean age 55.1±12.4 years) and 56 cases with stroke (46% male, mean age 46.9±15.2) were included and matched with control patients. In multivariable logistic regression analysis, traditional atherosclerotic risk factors (hypertension (OR 2.45; 95% CI 1.15 to 5.23), hypercholesterolaemia (OR 3.99; 95% CI 1.62 to 9.83) and smoking (OR 2.25; 95% CI 1.09 to 4.66)) were associated with CAD. In contrast, these risk factors were not associated with ischaemic stroke. In multivariable analysis, stroke was associated with previous shunt operations (OR 4.20; 95% CI 1.36 to 12.9), residual/unclosed septal defects (OR 2.38; 95% CI 1.03 to 5.51) and left-sided mechanical valves (OR 2.67; 95% CI 1.09 to 6.50).

Conclusions

Traditional atherosclerotic risk factors were associated with CAD in ACHD patients. In contrast, ischaemic stroke was related to factors (previous shunts, septal defects, mechanical valves) suggesting a cardioembolic aetiology. These findings may inform surveillance and prevention strategies.
Life-threatening perioperative anesthetic complications: major issues surrounding perioperative morbidity and mortality
Authors: Steadman Joy , Catalani Blas , Sharp Christopher , Cooper Lebron
Published: August 2017

Perioperative morbidity and mortality related to anesthesia involves multiple factors. Patient characteristics and comorbidities play a role in many of these events, highlighting the importance of preoperative screening. While optimization of patient comorbidities is not always possible, having data regarding those comorbidities can prove life-saving. Equipment and medication considerations also enter into untoward outcomes such as anesthetic interventions outside of the traditional operating room where resources are sometimes lacking and haste creates errors. Ultimately, when surgeons and anesthesiologists cooperate in patient care, communicating concisely but thoroughly, patients are more likely to do well. The language of surgeons is that of diagnosis requiring a surgical intervention, while anesthesiologists are discussing patient comorbidities impacted by anesthetic medications, positive pressure ventilation, neuraxial techniques, ramifications of patient positioning, effects of opiates and so on. Because all of the considerations combine in determining outcomes, it is incumbent on both surgeons and anesthesiologists to understand those elements leading to severe morbid events as well as death. This review touches on many of the most important factors.
An investigation on Ontario’s non-hazardous municipal solid waste diversion using trend analysis
Authors: Chowdhury Asma , Vu Hoang Lan , Ng Kelvin T.W. , Richter Amy , Bruce Nathan
Published: August 2017

Non-hazardous waste disposal and diversion trends in Ontario from 1996 to 2010 were identified using parametric and non-parametric statistical methods, and the temporal variability of its waste diversion practices were examined. Ontario’s diversion was sensitive to waste diversion policy and residential diversion programs. Total waste diversion increased by 85% in 14 years. Results suggested that waste minimization may be more effective than recycling on Ontario diversion rates. Programs targeting non-residential sectors are recommended, specifically for smaller businesses with limited waste management budgets. Linear regression and Mann-Kendall tests detected significant increasing trends for residential waste diversion. In contrast, non-residential diversion had a decreasing trend using linear regression. A significant upward trend (S = +10) was found for Ontario’s total waste diversion using Mann-Kendall tests. Highly significant upward trends were observed for plastic and organic recycling. Mann-Kendall tests were found more appropriate for waste trend analysis in the present study.
Microbial community structure and diversity within hypersaline Keke Salt Lake environments
Authors: Han Rui , Zhang Xin , Liu Jing , Long Qifu , Chen Laisheng , Liu Deli , Zhu Derui
Published: August 2017

Keke Salt Lake is located in the Qaidamu Basin of China. It is a unique magnesium sulfate-subtype hypersaline lake that exhibits a halite domain ecosystem, yet its microbial diversity has remained unstudied. Here, the microbial community structure and diversity was investigated via high-throughput sequencing of the V3–V5 regions of 16S rRNA genes. A high diversity of operational taxonomic units was detected for Bacteria and Archaea (734 and 747, respectively), comprising 21 phyla, 43 classes, and 201 genera of Bacteria and 4 phyla, 4 classes, and 39 genera of Archaea. Salt-saturated samples were dominated by the bacterial genera Bacillus (51.52%–58.35% relative abundance), Lactococcus (9.52%–10.51%), and Oceanobacillus (8.82%–9.88%) within the Firmicutes phylum (74.81%–80.99%), contrasting with other hypersaline lakes. The dominant Archaea belonged to the Halobacteriaceae family, and in particular, the genera (with an abundance of >10% of communities) Halonotius, Halorubellus, Halapricum, Halorubrum, and Natronomonas. Additionally, we report the presence of Nanohaloarchaeota and Woesearchaeota in Qinghai–Tibet Plateau lakes, which has not been previously documented. Total salinity (especially Mg2+, Cl–, Na+, and K+) mostly correlated with taxonomic distribution across samples. These results expand our understanding of microbial resource utilization within hypersaline lakes and the potential adaptations of dominant microorganisms that allow them to inhabit such environments.
Overwintering Steller sea lion (Eumetopias jubatus) pup growth and behavior prior to weaning
Authors: Rehberg M.J. , Rea L.D. , Eischens C.A.
Published: August 2017

We measured individual growth, looked for evidence of weaning, and examined the interaction of these changes with diving behavior in young-of-year Steller sea lion (Eumetopias jubatus (Schreber, 1776)) pups in Alaska, USA, during their first winter. Steller sea lions employ an income breeding strategy, in which females provision their young over an individually variable period of months to years. Thus, we set out to identify whether these young sea lions showed evidence of weaning during the challenging winter months, describe the nature of their growth during this time, and examine their behaviors in light of these changes. Between 2005 and 2008, we captured 71 pups during early winter and recaptured 33 of these pups in early spring. Mark–resight and stable nitrogen isotope ratios in vibrissae indicated most pups remained nutritionally dependent on adult females throughout the winter. All pups increased both mass and lipid mass, with half of growth contributed by lipid mass. Changes in behavior were not correlated with growth excepting a weak but significant effect on rate of vertical travel. This study demonstrated that capture–recapture of Steller sea lion pups is possible, provided seasonal timing, locations, and age classes are carefully considered for their likelihood of capture success.
Gene expression profiling analysis reveals fur development in rex rabbits (Oryctolagus cuniculus)
Authors: Zhao BoHao , Chen Yang , Yan XiaoRong , Hao Ye , Zhu Jie , Weng QiaoQing , Wu XinSheng
Published: August 2017

Fur is an important economic trait in rabbits. The identification of genes that influence fur development and knowledge regarding the actions of these genes provides useful tools for improving fur quality. However, the mechanism of fur development is unclear. To obtain candidate genes related to fur development, the transcriptomes of tissues from backs and bellies of Chinchilla rex rabbits were compared. Of the genes analyzed, 336 showed altered expression in the two groups (285 upregulated and 51 downregulated, P ≤ 0.05, fold-change ≥2 or ≤0.5). Using GO and KEGG to obtain gene classes that were differentially enriched, we found several genes to be involved in many important biological processes. In addition, we identified several signaling pathways involved in fur development, including the Wnt and MAPK signaling pathways, revealing mechanisms of skin and hair follicle development, and epidermal cell and keratinocytes differentiation. The obtained rabbit transcriptome and differentially expressed gene profiling data provided comprehensive gene expression information for SFRP2, FRZB, CACNG1, SLC25A4, and SLC16A3. To validate the RNA-seq data, the expression levels of eight differentially expressed genes involved in fur development were confirmed by qRT-PCR. The results of rabbit transcriptomic profiling provide a basis for understanding the molecular mechanisms of fur development.
Narrow pentaquarks as diquark–diquark–antiquark systems
Authors: Anisovich V. V. , Matveev M. A. , Nyiri J. , Semenova A. N.
Published: August 2017

The diquark–diquark–antiquark model describes pentaquark states both in terms of quarks and hadrons. The latest LHCb data for pentaquarks with open charm emphasize the importance of hadron components in the structure of pentaquarks. We discuss pentaquark states with hidden charm [Formula: see text] and those with open charm [Formula: see text] which were discovered recently in LHCb data ([Formula: see text] and [Formula: see text] spectra correspondingly). Considering the observed states as members of the lowest ([Formula: see text]-wave) multiplet, we discuss the mass splitting of states and the dumping of their widths.
A Modified PSO Algorithm for IIR Digital Filter Modeling
Authors: Chang Wei-Der
Published: August 2017

Modeling for an unknown plant is a very important and primary task in the control system engineering. By using this established model, an adequate controller can be further designed to meet certain control specifications. This paper will propose a new modeling method which is based on the infinite impulse response (IIR) digital filter structure. A modified particle swarm optimization (PSO) with multiple subpopulations is utilized to solve for the IIR filter coefficients to model an unknown digital system. The developed PSO algorithm is able to overcome the multimodal error surface problem that often occurs in the system modeling of IIR digital filter. Finally, three different kinds of digital systems are examined to demonstrate the feasibility of the proposed method, including the same system order and reduced order structures. It is concluded from several simulation results that the proposed method has an excellent performance on solving the IIR digital modeling problem.
Study of galactic halo F(T,TG) wormhole solutions
Authors: Sharif M. , Nazir Kanwal
Published: August 2017

In this paper, we investigate static spherically symmetric wormhole solutions with galactic halo region in the background of [Formula: see text] gravity. Here, [Formula: see text] represents torsion scalar and [Formula: see text] is teleparallel equivalent Gauss–Bonnet term. For this purpose, we consider a diagonal tetrad and two specific [Formula: see text] models. We analyze the wormhole structure through shape function graphically for both models. We also investigate the behavior of null/weak energy conditions. Finally, we evaluate the equilibrium condition to check stability of the wormhole solutions. It is concluded that there exists physically viable wormhole solution only for the first model that turns out to be stable.
Joint measurement of complementary observables in moment tomography
Authors: Teo Yong Siah , Müller Christian R. , Jeong Hyunseok , Hradil Zdeněk , Řeháček Jaroslav , Sánchez-Soto Luis L.
Published: August 2017

Wigner and Husimi quasi-distributions, owing to their functional regularity, give the two archetypal and equivalent representations of all observable-parameters in continuous-variable quantum information. Balanced homodyning (HOM) and heterodyning (HET) that correspond to their associated sampling procedures, on the other hand, fare very differently concerning their state or parameter reconstruction accuracies. We present a general theory of a now-known fact that HET can be tomographically more powerful than balanced homodyning to many interesting classes of single-mode quantum states, and discuss the treatment for two-mode sources.
Exciton scattering via algebraic topology
Authors: Catanzaro Michael J. , Chernyak Vladimir Y. , Klein John R.
Published: August 2017

This paper introduces an intersection theory problem for maps into a smooth manifold equipped with a stratification. We investigate the problem in the special case when the target is the unitary group [Formula: see text] and the domain is a circle. The first main result is an index theorem that equates a global intersection index with a finite sum of locally defined intersection indices. The local indices are integers arising from the geometry of the stratification.

The result is used to study a well-known problem in chemical physics, namely, the problem of enumerating the electronic excitations (excitons) of a molecule equipped with scattering data.
Dealing with Overleverage: Restricting Leverage vs. Restricting Variable Compensation
Authors: Gete Pedro , Gómez Juan-Pedro
Published: August 2017

We study policies that regulate executive compensation in a model that jointly determines executives’ effort, compensation and firm leverage. The market failure that justifies regulation is that executives are optimistic about asset prices in states of distress. We show that shareholders propose compensation packages that lead to socially excessive leverage. Say-on-pay regulation does not reduce the incentives for leverage. Regulating the structure of compensation (but not its level) with a cap on the ratio of variable-to-fixed pay delivers the right leverage. However, it is more efficient to directly regulate leverage because restricting the variable compensation impacts managerial effort more than if shareholders are free to design compensation subject to a leverage constraint.
Using Replicates in Information Retrieval Evaluation
Authors: Voorhees Ellen M. , Samarov Daniel , Soboroff Ian
Published: August 2017

This article explores a method for more accurately estimating the main effect of the system in a typical test-collection-based evaluation of information retrieval systems, thus increasing the sensitivity of system comparisons. Randomly partitioning the test document collection allows for multiple tests of a given system and topic (replicates). Bootstrap ANOVA can use these replicates to extract system-topic interactions—something not possible without replicates—yielding a more precise value for the system effect and a narrower confidence interval around that value. Experiments using multiple TREC collections demonstrate that removing the topic-system interactions substantially reduces the confidence intervals around the system effect as well as increases the number of significant pairwise differences found. Further, the method is robust against small changes in the number of partitions used, against variability in the documents that constitute the partitions, and the measure of effectiveness used to quantify system effectiveness.
Green-Energy-Powered Cognitive Radio Networks
Authors: Xu Chi , Liang Wei , Yu Haibin
Published: August 2017

This article studies a green-energy-powered cognitive radio network (GCRN) in an underlay paradigm, wherein multiple battery-free secondary users (SUs) capture both the spectrum and the energy of primary users (PUs) to communicate with an access point (AP). By time division multiple access, each SU transmits data to AP in the allocated time and harvests energy from the RF signals of PUs otherwise, all in the same licensed spectrum concurrently with PUs. Thus, the transmit power of each SU is jointly constrained by the peak interference power at PU and the harvested energy of SU. With the formulated green coexistence paradigm, we investigate the sum-throughput maximization problem with respect to time and power allocation, which is non-convex. To obtain the optimal resource allocation, we propose a joint optimal time and power allocation (JOTPA) algorithm that first transforms the original problem into a convex optimization problem with respect to time and energy allocation, and then solve it by iterative Lagrange dual decomposition. To comprehensively evaluate the performance of the GCRN with JOTPA, we deploy the GCRN in three typical scenarios and compare JOTPA with the equal time and optimal power allocation (ETOPA) algorithm. Extensive simulations show that the deployment of the GCRN significantly influences the throughput performance and JOTPA outperforms ETOPA under all considered scenarios.
Understanding and Leveraging the Impact of Response Latency on User Behaviour in Web Search
Authors: Bai Xiao , Arapakis Ioannis , Cambazoglu B. Barla , Freire Ana
Published: August 2017

The interplay between the response latency of web search systems and users’ search experience has only recently started to attract research attention, despite the important implications of response latency on monetisation of such systems. In this work, we carry out two complementary studies to investigate the impact of response latency on users’ searching behaviour in web search engines. We first conduct a controlled user study to investigate the sensitivity of users to increasing delays in response latency. This study shows that the users of a fast search system are more sensitive to delays than the users of a slow search system. Moreover, the study finds that users are more likely to notice the response latency delays beyond a certain latency threshold, their search experience potentially being affected. We then analyse a large number of search queries obtained from Yahoo Web Search to investigate the impact of response latency on users’ click behaviour. This analysis demonstrates the significant change in click behaviour as the response latency increases. We also find that certain user, context, and query attributes play a role in the way increasing response latency affects the click behaviour. To demonstrate a possible use case for our findings, we devise a machine-learning framework that leverages the latency impact, together with other features, to predict whether a user will issue any clicks on web search results. As a further extension of this use case, we investigate whether this machine-learning framework can be exploited to help search engines reduce their energy consumption during query processing.
AWARE
Authors: Ferrante Marco , Ferro Nicola , Maistro Maria
Published: August 2017

We propose theAssessor-driven Weighted Averages for Retrieval Evaluation (AWARE)probabilistic framework, a novel methodology for dealing with multiple crowd assessors that may be contradictory and/or noisy. By modeling relevance judgements and crowd assessors as sources of uncertainty, AWARE takes the expectation of a generic performance measure, like Average Precision, composed with these random variables. In this way, it approaches the problem of aggregating different crowd assessors from a new perspective, that is, directly combining the performance measures computed on the ground truth generated by the crowd assessors instead of adopting some classification technique to merge the labels produced by them. We propose several unsupervised estimators that instantiate the AWARE framework and we compare them with state-of-the-art approaches, that is,Majoriity Vote and Expectation Maximization, on TREC collections. We found that AWARE approaches improve in terms of their capability of correctly ranking systems and predicting their actual performance scores.
Data Analytics for Managing Power in Commercial Buildings
Authors: Bellala Gowtham , Marwah Manish , Arlitt Martin , Lyon Geoff , Bash Cullen , Shah Amip
Published: August 2017

Commercial buildings are significant consumers of electricity. We propose a number of methods for managing power in commercial buildings. The first step toward better energy management in commercial buildings is monitoring consumption. However, instrumenting every electrical panel in a large commercial building is an expensive proposition. In this article, we demonstrate that it is also unnecessary. Specifically, we propose a greedy meter (sensor) placement algorithm based on maximization of information gain subject to a cost constraint. The algorithm provides a near-optimal solution guarantee, and our empirical results demonstrate a 15% improvement in prediction power over conventional methods. Next, to identify power-saving opportunities, we use an unsupervised anomaly detection technique based on a low-dimensional embedding. Furthermore, to enable a building manager to effectively plan for demand response programs, we evaluate several solutions for fine-grained, short-term load forecasting. Our investigation reveals that support vector regression and an ensemble model work best overall. Finally, to better manage resources such as lighting and HVAC, we propose a semisupervised approach combining hidden Markov models (HMMs) and a standard classifier to model occupancy based on readily available port-level network statistics. We show that the proposed two-step approach simplifies the occupancy model while achieving good accuracy. The experimental results demonstrate an average occupancy estimation error of 9.3% with a potential reduction of 9.5% in lighting load using our occupancy models.
Faster coroutine pipelines
Authors: Spivey Michael
Published: August 2017

Coroutine pipelines provide an attractive structuring mechanism for complex programs that process streams of data, with the advantage over lazy streams that both ends of a pipeline may interact with the I/O system, as may processes in the middle. Two popular Haskell libraries, Pipes and Conduit, support such pipelines. In both libraries, pipelines are implemented in a direct style by combining a free monad of communication events with an interpreter for (pseudo-)parallel composition that interleaves the events of its argument processes. These implementations both suffer from a slow-down when processes are deeply nested in sequence or in parallel. We propose an alternative implementation of pipelines based on continuations that does not suffer from this slow-down. What is more, the implementation is significantly faster on small, communication-intensive examples even where they do not suffer from the slow-down, and comparable in speed with similar programs based on lazy streams. We also show that the continuation-based implementation may be derived from the direct-style implementation by algebraic reasoning.
Generic functional parallel algorithms: scan and FFT
Authors: Elliott Conal
Published: August 2017

Parallel programming, whether imperative or functional, has long focused on arrays as the central data type. Meanwhile, typed functional programming has explored a variety of data types, including lists and various forms of trees.
Generic
functional programming decomposes these data types into a small set of fundamental building blocks: sum, product, composition, and their associated identities. Definitions over these few fundamental type constructions then automatically assemble into algorithms for an infinite variety of data types—some familiar and some new. This paper presents generic functional formulations for two important and well-known classes of parallel algorithms: parallel scan (generalized prefix sum) and fast Fourier transform (FFT). Notably, arrays play no role in these formulations. Consequent benefits include a simpler and more compositional style, much use of common algebraic patterns and freedom from possibility of run-time indexing errors. The functional generic style also clearly reveals deep commonality among what otherwise appear to be quite different algorithms. Instantiating the generic formulations, two well-known algorithms for each of parallel scan and FFT naturally emerge, as well as two possibly new algorithms.
Prototyping a query compiler using Coq (experience report)
Authors: Auerbach Joshua S. , Hirzel Martin , Mandel Louis , Shinnar Avraham , Siméon Jérôme
Published: August 2017

Designing and prototyping new features is important in many industrial projects. Functional programming and formal verification tools can prove valuable for that purpose, but lead to challenges when integrating with existing product code or when planning technology transfer.

This article reports on our experience using the Coq proof assistant as a prototyping environment for building a query compiler intended for use in IBM's ODM Insights product. We discuss the pros and cons of using Coq for this purpose and describe our methodology for porting the compiler to Java, as required for product integration.
Persistence for the masses: RRB-vectors in a systems language
Authors: Puente Juan Pedro Bolívar
Published: August 2017

Relaxed Radix Balanced Trees (RRB-Trees) is one of the latest members in a family of persistent tree based data-structures that combine wide branching factors with simple and relatively flat structures. Like the battle-tested immutable sequences of Clojure and Scala, they have effectively constant lookup and updates, good cache utilization, but also logarithmic concatenation and slicing. Our goal is to bring the benefits of persistent data structures to the discipline of systems programming via generic yet efficient immutable vectors supporting transient batch updates. We describe a C++ implementation that can be integrated in the runtime of higher level languages with a C core (Lisps like Guile or Racket, but also Python or Ruby), thus widening the access to these persistent data structures.

In this work we propose (1) an
Embedding RRB-Tree
(ERRB-Tree) data structure that efficiently stores arbitrary unboxed types, (2) a technique for implementing tree operations orthogonal to optimizations for a more compact representation of the tree, (3) a
policy-based
design to support multiple memory management and reclamation mechanisms (including automatic garbage collection and reference counting), (4) a model of
transience
based on move-semantics and reference counting, and (5) a definition of transience for confluent
meld
operations. Combining these techniques a performance comparable to that of mutable arrays can be achieved in many situations, while using the data structure in a functional way.
Foundations of strong call by need
Authors: Balabonski Thibaut , Barenbaum Pablo , Bonelli Eduardo , Kesner Delia
Published: August 2017

We present a call-by-need strategy for computing strong normal forms of open terms (reduction is admitted inside the body of abstractions and substitutions, and the terms may contain free variables), which guarantees that arguments are only evaluated when needed and at most once. The strategy is shown to be complete with respect toβ-reduction to strong normal form. The proof of completeness relies on two key tools: (1) the definition of a strong call-by-need calculus where reduction may be performed inside any context, and (2) the use of non-idempotent intersection types. More precisely, terms admitting aβ-normal form in pure lambda calculus are typable, typability implies (weak) normalisation in the strong call-by-need calculus, and weak normalisation in the strong call-by-need calculus implies normalisation in the strong call-by-need strategy. Our (strong) call-by-need strategy is also shown to be conservative over the standard (weak) call-by-need.
Parametric quantifiers for dependent type theory
Authors: Nuyts Andreas , Vezzosi Andrea , Devriese Dominique
Published: August 2017

Polymorphic type systems such as System F enjoy the parametricity property: polymorphic functions cannot inspect their type argument and will therefore apply the same algorithm to any type they are instantiated on. This idea is formalized mathematically in Reynolds's theory of relational parametricity, which allows the metatheoretical derivation of parametricity theorems about all values of a given type. Although predicative System F embeds into dependent type systems such as Martin-Löf Type Theory (MLTT), parametricity does not carry over as easily. The identity extension lemma, which is crucial if we want to prove theorems involving equality, has only been shown to hold for small types, excluding the universe.

We attribute this to the fact that MLTT uses a single type former Π to generalize both the parametric quantifier ∀ and the type former → which is non-parametric in the sense that its elements may use their argument as a value. We equip MLTT with parametric quantifiers ∀ and ∃ alongside the existing Π and Σ, and provide relation type formers for proving parametricity theorems internally. We show internally the existence of initial algebras and final co-algebras of indexed functors both by Church encoding and, for a large class of functors, by using sized types.

We prove soundness of our type system by enhancing existing iterated reflexive graph (cubical set) models of dependently typed parametricity by distinguishing between edges that express relatedness of objects (bridges) and edges that express equality (paths). The parametric functions are those that map bridges to paths.

We implement an extension to the Agda proof assistant that type-checks proofs in our type system.
Normalization by evaluation for sized dependent types
Authors: Abel Andreas , Vezzosi Andrea , Winterhalter Theo
Published: August 2017

Sized types have been developed to make termination checking more perspicuous, more powerful, and more modular by integrating termination into type checking. In dependently-typed proof assistants where proofs by induction are just recursive functional programs, the termination checker is an integral component of the trusted core, as validity of proofs depend on termination. However, a rigorous integration of full-fledged sized types into dependent type theory is lacking so far. Such an integration is non-trivial, as explicit sizes in proof terms might get in the way of equality checking, making terms appear distinct that should have the same semantics.

In this article, we integrate dependent types and sized types with higher-rank size polymorphism, which is essential for generic programming and abstraction. We introduce a size quantifier ∀ which lets us ignore sizes in terms for equality checking, alongside with a second quantifier Π for abstracting over sizes that do affect the semantics of types and terms. Judgmental equality is decided by an adaptation of normalization-by-evaluation for our new type theory, which features
type shape
-directed reflection and reification. It follows that subtyping and type checking of normal forms are decidable as well, the latter by a bidirectional algorithm.
Gradual session types
Authors: Igarashi Atsushi , Thiemann Peter , Vasconcelos Vasco T. , Wadler Philip
Published: August 2017

Session types are a rich type discipline, based on linear types, that lift the sort of safety claims that come with type systems to communications. However, web-based applications and micro services are often written in a mix of languages, with type disciplines in a spectrum between static and dynamic typing. Gradual session types address this mixed setting by providing a framework which grants seamless transition between statically typed handling of sessions and any required degree of dynamic typing.

We propose GradualGV as an extension of the functional session type system GV with dynamic types and casts. We demonstrate type and communication safety as well as blame safety, thus extending previous results to functional languages with session-based communication. The interplay of linearity and dynamic types requires a novel approach to specifying the dynamics of the language.
Gradual typing with union and intersection types
Authors: Castagna Giuseppe , Lanvin Victor
Published: August 2017

We propose a type system for functional languages with gradual types and set-theoretic type connectives and prove its soundness. In particular, we show how to lift the definition of the domain and result type of an application from non-gradual types to gradual ones and likewise for the subtyping relation. We also show that deciding subtyping for gradual types can be reduced in linear time to deciding subtyping on non-gradual types and that the same holds true for all subtyping-related decision problems that must be solved for type inference. More generally, this work not only enriches gradual type systems with unions and intersections and with the type precision that arise from their use, but also proposes and advocates a new style of gradual types programming where union and intersection types are used by programmers to instruct the system to perform fewer dynamic checks.
Algorithm 985
Authors: Zaghloul Mofreh R.
Published: August 2017

We present a new simple algorithm for efficient, and relatively accurate computation of the Faddeyeva function
w
(
z
). The algorithm carefully exploits previous approximations by Hui et al. (1978) and Humlíček (1982) along with asymptotic expressions from Laplace continued fractions. Over a wide and fine grid of the complex argument,
z = x + iy
, numerical results from the present approximation show a maximum relative error less than 4.0 × 10
−5
for both real and imaginary parts of
w
while running in a relatively shorter execution time than other competitive techniques. In addition to the calculation of the Faddeyeva function,
w
, partial derivatives of the real and imaginary parts of the function can easily be calculated and returned as optional output.
K0-K¯0 Mixing in the Minimal Flavor-Violating Two-Higgs-Doublet Models
Authors: Cho Natthawin , Li Xin-Qiang , Su Fang , Zhang Xin
Published: August 2017

The two-Higgs-doublet model (2HDM), as one of the simplest extensions of the Standard Model (SM), is obtained by adding another scalar doublet to the SM and is featured by a pair of charged Higgs, which could affect many low-energy processes. In the “Higgs basis” for a generic 2HDM, only one scalar doublet gets a nonzero vacuum expectation value and, under the criterion of minimal flavor violation, the other one is fixed to be either color-singlet or color-octet, which are named as type III and type C 2HDM, respectively. In this paper, we study the charged-Higgs effects of these two models on the K0-K¯0 mixing, an ideal process to probe New Physics (NP) beyond the SM. Firstly, we perform a complete one-loop computation of the box diagrams relevant to the K0-K¯0 mixing, keeping the mass and momentum of the external strange quark up to the second order. Together with the up-to-date theoretical inputs, we then give a detailed phenomenological analysis, in the cases of both real and complex Yukawa couplings of the charged Higgs to quarks. The parameter spaces allowed by the current experimental data on the mass difference ΔmK and the CP-violating parameter ϵK are obtained and the differences between these two 2HDMs are investigated, which are helpful to distinguish them from each other from a phenomenological point of view.
Child-Pugh Parameters and Platelet Count as an Alternative to ICG Test for Assessing Liver Function for Major Hepatectomy
Authors: Au Kin-Pan , Chan See-Ching , Chok Kenneth Siu-Ho , Chan Albert Chi-Yan , Cheung Tan-To , Ng Kelvin Kwok-Chai , Lo Chung-Mau
Published: August 2017

Objective. To study the correlations and discrepancies between Child-Pugh system and indocyanine green (ICG) clearance test in assessing liver function reserve and explore the possibility of combining two systems to gain an overall liver function assessment. Design. Retrospective analysis of 2832 hepatocellular carcinoma (HCC) patients graded as Child-Pugh A and Child-Pugh B with ICG clearance test being performed was conducted. Results. ICG retention rate at 15 minutes (ICG15) correlates with Child-Pugh score, however, with a large variance. Platelet count improves the correlation between Child-Pugh score and ICG15. ICG15 can be estimated using the following regression formula: estimated ICG15 (eICG15) = 45.1 + 0.435 × bilirubin − 0.917 × albumin + 0.491 × prothrombin time − 0.0283 × platelet (R2=0.455). Patients with eICG15 >20.0% who underwent major hepatectomy had a tendency towards more posthepatectomy liver failure (4.1% versus 8.0%, p=0.09) and higher in-hospital mortality (3.7% versus 8.0%, p=0.052). They also had shorter median overall survival (5.10±0.553 versus 3.01±0.878 years, p=0.015) and disease-free survival (1.37±0.215 versus 0.707±0.183 years, p=0.018). Conclusion. eICG15 can be predicted from Child-Pugh parameters and platelet count. eICG15 correlates with in-hospital mortality after major hepatectomy and predicts long-term survival.
Amelioration of Ethanol-Induced Hepatitis by Magnesium Isoglycyrrhizinate through Inhibition of Neutrophil Cell Infiltration and Oxidative Damage
Authors: Wang Yan , Zhang Zhenzhen , Wang Xia , Qi Dan , Qu Aijuan , Wang Guiqiang
Published: August 2017

Alcoholic liver disease (ALD) is a leading cause of liver-related morbidity and mortality worldwide. There is no effective treatment to prevent the disease progression. Magnesium isoglycyrrhizinate (MgIG) showed potent anti-inflammatory, antioxidant, and hepatoprotective activities and was used for treating liver diseases in Asia. In this study, we examined whether MgIG could protect mice against alcohol-induced liver injury. The newly developed chronic plus binge ethanol feeding model was used to study the role of MgIG in ALD. Serum liver enzyme levels, H&E staining, immunohistochemical staining, flow cytometric analysis, and real-time PCR were used to evaluate the liver injury and inflammation. We showed that MgIG markedly ameliorated chronic plus binge ethanol feeding liver injury, as shown by decreased serum alanine transaminase and aspartate aminotransferase levels and reduced neutrophil infiltration. The reason may be attributed to the reduced expression of proinflammatory cytokines and chemokines with the treatment of MgIG. The hepatoprotective effect of MgIG was associated with suppression of neutrophil ROS production as well as hepatocellular oxidative stress. MgIG may play a critical role in protecting against chronic plus binge ethanol feeding-induced liver injury by regulating neutrophil activity and hepatic oxidative stress.
A New Technique Using Low Volumes: A New Technique to Assess the Molluscicidal Activity Using Low Volumes
Authors: Santos José Augusto Albuquerque , Cavalcante Viviane Paixão , Rangel Leonardo da Silva , Leite João Claudio Vitória Atico , Faria Robson Xavier
Published: August 2017

Schistosomiasis is a disease endemic in several states of Brazil. The population control of the transmitter mollusks is done with Bayluscide WP 70®, in the control programs. OMS preconize molluscicidal assays using Becker with 500 mL of final volume, restringing the number of natural products and synthetic drugs to be tested in function of high quantity of material necessary. A new technique to assess the toxic effects for Biomphalaria sp. is the purpose of this work, for developing adaptation for this aquatic organism, using a low volume of test solution in 24‐well plates. We used Biomphalaria glabrata (10–12 mm size) in a static system, consisting of the following components: Becker containing 10 snails or 24‐well plates where snails were individualized for a volume of 2 mL per well for 24 and 48 hours. For the assays, we added aqueous solutions of Bayluscide WP 70, at a concentration of 1–5 mg/L, distilled water, and 1% dimethyl sulfoxide. Data were evaluated using Kappa’s coefficient, Z factor validation, and comparison study. This technique to assess the toxic effect has proven to be a useful tool to detect lethal and sublethal effects, which could be used as a new evaluation protocol.