bluuebunny/crossref_metadata_2025 huggingface dataset:
Toxicological Profile and Pharmacokinetics of a Unilamellar Liposomal Vesicle Formulation of Amphotericin B in Rats
Authors: Boswell Garry W. , Bekersky Ihor , Buell Donald , Hiles Richard , Walsh Thomas J.
Published: April 2020

AmBisome (ABLP) is a unilamellar liposomal preparation of amphotericin B that has demonstrated an improved safety profile compared to conventional amphotericin B. Single- and multiple-dose pharmacokinetics were determined by using noncompartmental methods for rats administered ABLP at 1, 3, 9, and 20 mg/kg/day. The toxicological profile was evaluated following 30 consecutive days of intravenous ABLP administration. Mean plasma amphotericin B concentrations reached 500 and 380 μg/ml (males and females, respectively) following 30 days of ABLP administration at 20 mg/kg. The overall apparent half-life was 11.2 ± 4.5 h (males) or 8.7 ± 2.2 h (females), and the overall clearance (CL) was 9.4 ± 5.5 ml/h/kg (males) or 10.2 ± 4.1 ml/h/kg (females). ABLP appears to undergo saturable disposition, resulting in a non-dose-proportional amphotericin B area under the curve and a lower CL at higher doses. Histopathological examination revealed dose-related transitional-cell hyperplasia in the transitional epithelium of the urinary tract (kidney, ureters, and urinary bladder) and moderate hepatocellular necrosis at the 20-mg/kg/day dose. Administration of ABLP in doses of up to 20 mg/kg/day resulted in 100-fold higher plasma amphotericin B concentrations, with significantly lower toxicity than that reported with conventional amphotericin B therapy.
Stereoselective Disposition of Sulbenicillin in Humans
Authors: Itoh Tomoo , Watanabe Naoko , Ishida Mariko , Tsuda Yasuyuki , Koyano Shinichi , Tsunoi Tomoko , Shimada Hideyo , Yamada Hideo
Published: April 2020

Stereoselective disposition of sulbenicillin (SBPC) epimers in healthy human volunteers was studied in order to clarify the differences in pharmacokinetic behavior between the epimers. Stereospecific high-performance liquid chromatography was used for the determination of SBPC epimers. Plasma protein binding was measured in vitro with an ultrafiltration method. The binding was stereoselective, with the unbound fraction (

f
u

) of the
R
-epimer being approximately 1.3-fold greater than that of the
S
-epimer. SBPC was administered intravenously to human volunteers, and concentrations of SBPC in plasma and urinary excretion rates were measured. Renal clearance (CL
R
) for the unbound drug (approximately 400 ml/min) was greater than the glomerular filtration rate (GFR) (approximately 109 ml/min) for both epimers, suggesting that both epimers are secreted at the renal tubules. Renal tubular secretion appeared to be greater for the
S
-epimer. When probenecid was coadministered, the CL
R
values of both epimers were significantly reduced and were approximately equal to the GFR values. CL
R
was greater for the
S
-epimer (37.5 and 49.8 ml/min for
R
-SBPC and
S
-SBPC, respectively), which was simply due to the greater

f
u

of the
S
-epimer in plasma. In contrast, total body clearance was greater for the
R
-epimer (67.8 and 56.3 ml/min for
R
-SBPC and
S
-SBPC, respectively) because of the stereoselective degradation of the
R
-epimer in plasma. It was revealed that stereoselective degradation in the body had significant influence on the disposition of SBPC epimers.
TXU (Anti-CD7)-Pokeweed Antiviral Protein as a Potent Inhibitor of Human Immunodeficiency Virus
Authors: Uckun Fatih M. , Chelstrom Lisa M. , Tuel-Ahlgren Lisa , Dibirdik Ilker , Irvin James D. , Langlie Mridula-Chandan , Myers Dorothea E.
Published: April 2020

We have evaluated the clinical potential of TXU (anti-CD7)-pokeweed antiviral protein (PAP) immunoconjugate (TXU-PAP) as a new biotherapeutic anti-human immunodeficiency virus (anti-HIV) agent by evaluating its anti-HIV type 1 (anti-HIV-1) activity in vitro, as well as in a surrogate human peripheral blood lymphocyte-severe combined immunodeficient (Hu-PBL-SCID) mouse model of human AIDS. The present report documents in a side-by-side comparison the superior in vitro anti-HIV-1 activity of TXU-PAP compared to the activities of zidovudine, 2′,3′-didehydro-2′,3′-dideoxythymidine, unconjugated PAP, and B53-PAP, an anti-CD4-PAP immunoconjugate. Notably, TXU-PAP elicited potent anti-HIV activity in the Hu-PBL-SCID mouse model of human AIDS without any side effects and at doses that were very well tolerated by cynomolgus monkeys. Furthermore, plasma samples from TXU-PAP-treated cynomolgus monkeys showed potent anti-HIV-1 activity in vitro.
Postantibiotic and Sub-MIC Effects of Azithromycin and Isepamicin against
Staphylococcus aureus
and
Escherichia coli
Authors: Fuentes F. , Izquierdo J. , Martín M. M. , Gomez-Lus M. L. , Prieto J.
Published: April 2020

Investigations of pharmacodynamic parameters (postantibiotic effect [PAE], sub-MIC effects [SMEs], etc.) have been progressively employed for the design of dosing schedules of antimicrobial agents. However, there are fewer in vivo than in vitro data, probably because of the simplicity of the in vitro procedures. In this study, we have investigated the in vitro PAE, SME, and previously treated (postantibiotic [PA]) SME (1/2 MIC, 1/4 MIC and 1/8 MIC) of azithromycin and isepamicin against standard strains of
Staphylococcus aureus
and
Escherichia coli
by using centrifugation to remove the antibiotics. In addition, the in vivo PAE and SME have been studied with the thigh infection model in neutropenic mice. Finally, in vivo killing curves with two dosing schedules were determined to examine whether the PAE can cover the time that antimicrobial agents are below the MIC. The two antimicrobial agents induced moderate-to-high in vitro PAEs, SMEs, and PA SMEs against
S. aureus
(>8 h) and
E. coli
(3.38 to >7.64 h). The in vivo PAEs were also high (from 3.0 to 3.6 h), despite the fact that isepamicin had lower times above the MIC in serum. Only azithromycin showed a high in vivo SME against the two strains (1.22 and 1.75 h), which indicated that the in vivo PAEs were possibly overestimated. In the killing kinetics, no great differences (<0.5 log
10
) were observed between the schedule that took the PAE into account and the continuous administration of doses. These results are comparable with those of other authors and suggest that these antimicrobial agents could be administered at longer intervals without losing effectiveness.
Effects of Probenecid and Cimetidine on Renal Disposition of Ofloxacin in Rats
Authors: Foote Edward F. , Halstenson Charles E.
Published: April 2020

The renal handling of ofloxacin in rats which were given ofloxacin either alone or in combination with probenecid or cimetidine was studied. In the presence of cimetidine or probenecid, ofloxacin’s total and renal clearances were reduced and its half-life was prolonged. This suggests that ofloxacin is secreted by both the anionic and cationic transport systems.
Characterization of FOX-3, an AmpC-Type Plasmid-Mediated β-Lactamase from an Italian Isolate of
Klebsiella oxytoca
Authors: Marchese Anna , Arlet Guillaume , Schito Gian Carlo , Lagrange Philippe H. , Philippon Alain
Published: April 2020

Klebsiella oxytoca
1731, which showed a wide spectrum of resistance to β-lactams, including cefoxitin, was isolated in 1994 from a patient in Genoa, Italy. This strain contained a plasmid-mediated AmpC β-lactamase with a pI of 7.25. Sequencing of the corresponding DNA of
K. oxytoca
1731 revealed 96 and 97% identities of the deduced amino acid sequence with FOX-1 and FOX-2, respectively.
Dual Function of Aar, a Member of the New AraC Negative Regulator Family, in Escherichia coli Gene Expression
Authors: Mickey Abigail S. , Nataro James P.
Published: April 2020

Enteroaggregative
Escherichia coli
(EAEC) is an
E. coli
pathotype associated with diarrhea and growth faltering. EAEC virulence gene expression is controlled by the autoactivated AraC family transcriptional regulator, AggR. AggR activates transcription of a large number of virulence genes, including Aar, which in turn acts as a negative regulator of AggR itself. Aar has also been shown to affect expression of
E. coli
housekeeping genes, including H-NS, a global regulator that acts at multiple promoters and silences AT-rich genes (such as those in the AggR regulon).
Supplemental Material: The Chief Joseph dike swarm of the Columbia River flood basalts, and the legacy data set of William H. Taubeneck
Authors: Morriss M.C.
Published: April 2020

Supplemental ArcGIS Shapefiles. Shapefiles for mapped dikes used in maps throughout paper.
Practical approach to extensive cutaneous spread without any underlying malignancy: a rare presentation of Paget’s disease of breast
Authors: Lakhera Kamal Kishore , Patni Sanjeev , Patni Nidhi , Jindal Rohit
Published: April 2020

Paget’s disease of the breast is a rare intraepithelial malignancy involving the nipple–areola complex, often associated with an underlying in-situ or invasive carcinoma in the breast parenchyma. Most of the cases disease is usually limited to nipple–areola or surrounding periareolar skin. We are reporting a case of extensive Paget’s disease, involving entire breast skin and even part of abdominal wall skin without any underlining breast pathology, which is a rare presentation.
Visual outcomes after surgery for primary rhegmatogenous retinal detachment in era of microincision vitrectomy: Japan-Retinal Detachment Registry Report IV
Authors: Baba Takayuki , Kawasaki Ryo , Yamakiri Keita , Koto Takashi , Nishitsuka Koichi , Yamamoto Shuichi , Sakamoto Taiji
Published: April 2020

Background/Aim

To determine the preoperative ocular factors and surgical methods that led to best-corrected visual acuity (BCVA) after pars plana vitrectomy (PPV) or scleral buckling (SB) for rhegmatogenous retinal detachment (RRD).

Methods

This was a prospective, nationwide, multicentre, observational study. Data from the Japanese Retina and Vitreous Society registry from 2016 to 2017 were used to determine the association between preoperative clinical factors, surgical procedures and postoperative BCVA at 6 months. Japanese individuals >40 years of age were included. Eyes with proliferative vitreoretinopathy were included. The primary outcome was the percentage of eyes that achieved 20/25 vision.

Results

Of the 3219 registered cases, 2192 met the inclusion criteria (344 SB, 1738 PPV, 110 PPV+SB). Cases with preoperative BCVA (≤0 logarithm of the minimum angle of resolution (logMAR) units) had good postoperative BCVA (OR=3.97, CI 2.87 to 5.51). Older age (>70 years), low intraocular pressure (<10 mm Hg), high myopia (<−5 dioptres), multiple retinal breaks (>4), giant retinal tear (>90°), wide retinal detachment (>3 quadrants) and macula-off detachment were associated with less probability of postoperative 20/25 vision (OR=0.39, 0.64, 0.62, 0.60, 0.12, 0.51 and 0.36, respectively). Postoperative BCVA was 0.03±0.23 and 0.10±0.32 logMAR units after SB and PPV, respectively. The percentage of cases that achieved 20/25 vision was not significantly different after PPV or SB if cases that had concurrent cataract surgery were excluded (p=0.251).

Conclusions

Better BCVA in patients with RRD who had undergone PPV was observed. However, if concurrent cataract surgery is not performed, BCVA will be comparable with either PPV or SB.
Design and validation of a patient-reported outcome measure scale in acute pancreatitis: the PAN-PROMISE study
Authors: de-Madaria Enrique , Sánchez-Marin Claudia , Carrillo Irene , Vege Santhi Swaroop , Chooklin Serge , Bilyak Andriy , Mejuto Rafael , Mauriz Violeta , Hegyi Peter , Márta Katalin , Kamal Ayesha , Lauret-Braña Eugenia , Barbu Sorin T , Nunes Vitor , Ruiz-Rebollo M Lourdes , García-Rayado Guillermo , Lozada-Hernandez Edgard E , Pereira Jorge , Negoi Ionut , Espina Silvia , Hollenbach Marcus , Litvin Andrey , Bolado-Concejo Federico , Vargas Rómulo D , Pascual-Moreno Isabel , Singh Vikesh K , Mira José J
Published: April 2020

Objective

This study aimed to develop and validate a patient-reported outcome measure (PROM) in acute pancreatitis (AP) as an endpoint centred on the patient.

Design

A PROM instrument (PAtieNt-rePoRted OutcoMe scale in acute pancreatItis, an international proSpEctive cohort study, PAN-PROMISE scale) was designed based on the opinion of patients, professionals and an expert panel. The scale was validated in an international multicentre prospective cohort study, describing the severity of AP and quality of life at 15 days after discharge as the main variables for validation. The COSMIN (COnsensus-based Standards for the selection of health status Measurement INstruments) methodology was applied. Both the design and validation stages considered the content and face validity of this new instrument; the metric properties of the different items, reliability (reproducibility and internal consistence), the construct, structural and criterion validity, responsiveness and interpretability of this scale.

Results

PAN-PROMISE consists of a seven-item scale based on the symptoms that cause the most discomfort and concern to patients with AP. The validation cohort involved 15 countries, 524 patients. The intensity of symptoms changed from higher values during the first 24 hours to lower values at discharge and 15 days thereafter. Items converged into a unidimensional ordinal scale with good fit indices. Internal consistency and split-half reliability at discharge were adequate. Reproducibility was confirmed using test–retest reliability and comparing the PAN-PROMISE score at discharge and 15 days after discharge. Evidence is also provided for the convergent-discriminant and empirical validity of the scale.

Conclusion

The PAN-PROMISE scale is a useful tool to be used as an endpoint in clinical trials, and to quantify patient well-being during the hospital admission and follow-up.

Trial registration number

NCT03650062
Thoughts on COVID-19 and autoimmune diseases
Authors: Askanase Anca D , Khalili Leila , Buyon Jill P
Published: April 2020

Over the 2 months since coronavirus first appeared in China, cases have emerged on every continent, and it is clear that patients with autoimmune diseases might also be affected. Coronavirus disease 2019 (COVID-19) is a highly contagious viral illness with a mortality rate approaching 2%. Here we discuss the challenges that patients with autoimmune diseases might face and the information on using immunomodulatory therapies like chloroquine, tocilizumab and baricitinib to quench the cytokine storm in patients with very severe COVID-19 pneumonia.
Comparing outcomes after peripheral nerve block versus general anesthesia for lower extremity amputation: a nationwide exploratory retrospective cohort study in Japan
Authors: Abe Hiroaki , Sumitani Masahiko , Matsui Hiroki , Aso Shotaro , Inoue Reo , Fushimi Kiyohide , Uchida Kanji , Yasunaga Hideo , Yamada Yoshitsugu
Published: April 2020

Background and objectives

The health benefits of peripheral nerve block (PNB) on postoperative complications after lower extremity amputation (LEA) compared with general anesthesia (GA) remains controversial. We performed a retrospective propensity score-matched cohort analysis to compare major outcomes after LEA with PNB versus GA.

Materials and methods

We used a nationwide inpatient database in Japan to compare patient outcomes after LEA with PNB versus GA from 2010 to 2016. Our primary outcome was 30-day mortality after LEA. The incidence of composite morbidity from life-threatening complications and of delirium within 30 days after LEA were secondary outcomes. We conducted propensity score-matched analyses of patients who underwent below knee or foot amputation using 36 covariates. Logistic regression analyses fitted with generalized estimating equations were performed to calculate ORs and their 95% CIs.

Results

Of 11 796 patients, 747 received PNB and 11 049 received GA. After one-to-four propensity score matching, 747 patients were included in the PNB group and 2988 in the GA group. The adjusted ORs for postoperative mortality, composite morbidity and delirium within 30 days after LEA were 1.11 (95% CI 0.75 to 1.64), 1.15 (95% CI 0.85 t o1.56) and 0.75 (95% CI 0.57 to 0.98), respectively, for the PNB group with reference to the GA group.

Conclusions

There was no significant difference between groups in 30-day mortality or composite morbidity. The PNB group showed a significantly lower risk of postoperative delirium than the GA group. Our findings suggest that PNB may have advantages over GA in preventing postoperative delirium among patients undergoing LEA.
Designing and implementing a practical prehospital emergency trauma care curriculum for lay first responders in Guatemala
Authors: Delaney Peter G , Figueroa Jose A , Eisner Zachary J , Hernandez Andrade Rudy Erik , Karmakar Monita , Scott John W , Raghavendran Krishnan
Published: April 2020

Background

Injury disproportionately affects low-income and middle-income countries, yet robust emergency medical services are often lacking to effectively address the prehospital injury burden. A half-day prehospital emergency trauma care curriculum was designed for first responders and piloted in the Sacatepéquez, Chimaltenango, and Escuintla departments in Guatemala.

Methods

Three hundred and fifty-four law enforcement personnel, firefighters, and civilians volunteered to participate in a 5-hour emergency care course teaching scene safety, triage, airway management, cardiopulmonary resuscitation, fracture management, and victim transport. A validated 26-question pretest/post-test study instrument was contextually adapted and used to measure overall test performance, the primary study outcome, as well as test performance stratified by occupation, the secondary study outcome. Pretest/post-test score distributions were compared using a Wilcoxon signed-rank test. For test evaluation, knowledge acquisition on a by-question and by-category basis was examined using McNemar’s χ² test, whereas item difficulty indices used frequency-of-distribution tests and item discrimination indices used point biserial correlation.

Results

Two hundred and eighty-seven participants qualified for inclusion. Participant mean pretest versus post-test scores improved 24 percentage points after course completion (43% vs 68%, p<0.001). Cronbach’s alpha yielded values of 0.86 (pretest) and 0.94 (post-test), suggesting testing instrument reliability. Between-group analyses demonstrated law enforcement and civilian participants improved more than firefighters (p<0.001). Performance on 23 of 26 questions improved significantly. All test questions except one showed an increase in their PPDI.

Discussion

A 1-day, contextually adapted, 5-hour course targeting laypeople demonstrates significant improvements in emergency care knowledge. Future investigations of similar curricula should be trialed in alternate low-resource settings with increased civilian participation to evaluate efficacy and replicability as adequate substitutes for longer courses. This study suggests future courses teaching emergency care for lay first responders may be reduced to 5 hours duration.

Level of evidence

Level II.
Fake news propagates differently from real news even at early stages of spreading
Authors: Zhao Zilong , Zhao Jichang , Sano Yukie , Levy Orr , Takayasu Hideki , Takayasu Misako , Li Daqing , Wu Junjie , Havlin Shlomo
Published: April 2020

Social media can be a double-edged sword for society, either as a convenient channel exchanging ideas or as an unexpected conduit circulating fake news through a large population. While existing studies of fake news focus on theoretical modeling of propagation or identification methods based on machine learning, it is important to understand the realistic propagation mechanisms between theoretical models and black-box methods. Here we track large databases of fake news and real news in both, Weibo in China and Twitter in Japan from different cultures, which include their traces of re-postings. We find in both online social networks that fake news spreads distinctively from real news even at early stages of propagation, e.g. five hours after the first re-postings. Our finding demonstrates collective structural signals that help to understand the different propagation evolution of fake news and real news. Different from earlier studies, identifying the topological properties of the information propagation at early stages may offer novel features for early detection of fake news in social media.
Commentary on The Nürnberg Funnel
Authors: Horn Robert E.
Published: April 2020

The frontispiece of this book shows a plump, happy faced youth dressed in the clothes of several hundred years ago with a funnel sticking out of the top of his head. Two teachers are industriously pouring large amounts of liquid knowledge into his head. This is the Nürnberg Funnel. It was supposed to "makes people wise quickly." But the author of this book says, "There is not and never was a Nürnberg Funnel." (p. 102) "Nevertheless the need to make people wise very quickly is often overwhelming. And in trying to make instruction efficient, designers have frequently lapsed into trying to pour information into the learner's head.
Validate, simulate, and implement ARINC653 systems using the AADL
Authors: Delange Julien , Pautet Laurent , Plantec Alain , Kerboeuf Mickael , Singhoff Frank , Kordon Fabrice
Published: April 2020

Safety-critical systems are widely used in different domains and lead to an increasing complexity. Such systems rely on specific services such space and time isolation as in the ARINC653 avionics standard. Their criticality requires a carefully driven design based on an appropriate development process and dedicated tools to detect and avoid problems as early as possible.

Model Driven Engineering (MDE) approaches are now considered as valuable approach for building safety-critical systems. The Architecture Analysis and Design Language (AADL) proposes a component-based language suitable to operate MDE that fits with safety-critical systems needs.

This paper presents an approach for the modeling, verification and implementation of ARINC653 systems using AADL. It details a modeling approach exploiting the new features of AADL version 2 for the design of ARINC653 architectures. It also proposes modeling patterns to represent other safety mechanisms such as the use of Ravenscar for critical applications. This approach is fully backed by tools with Ocarina (AADL toolsuite), POK (AADL/ARINC653 runtime) and Cheddar (scheduling verification). Thus, it assists system engineers to simulate and validate non functional requirements such as scheduling or resources dimensioning.
Investigating the safe evolution of software product lines
Authors: Neves Laís , Teixeira Leopoldo , Sena Demóstenes , Alves Vander , Kulesza Uirá , Borba Paulo
Published: April 2020

The adoption of a product line strategy can bring significant productivity and time to market improvements. However, evolving a product line is risky because it might impact many products and their users. So when evolving a product line to introduce new features or to improve its design, it is important to make sure that the behavior of existing products is not affected. In fact, to preserve the behavior of existing products one usually has to analyze different artifacts, like feature models, configuration knowledge and the product line core assets. To better understand this process, in this paper we discover and analyze concrete product line evolution scenarios and, based on the results of this study, we describe a number of safe evolution templates that developers can use when working with product lines. For each template, we show examples of their use in existing product lines. We evaluate the templates by also analyzing the evolution history of two different product lines and demonstrating that they can express the corresponding modifications and then help to avoid the mistakes that we identified during our analysis.
HACMS
Authors: Fisher Kathleen
Published: April 2020

Embedded systems form a ubiquitous, networked, computing substrate that underlies much of modern technological society. Such systems range from large supervisory control and data acquisition (SCADA) systems that manage physical infrastructure to medical devices such as pace-makers and insulin pumps, to computer peripherals such as printers and routers, to communication devices such as cell phones and radios, to vehicles such as airplanes and satellites. Such devices have been networked for a variety of reasons, including the ability to conveniently access diagnostic information, perform software updates, provide innovative features, lower costs, and improve ease of use. Researchers and hackers have shown that these kinds of networked embedded systems are vulnerable to remote attack, and such attacks can cause physical damage while hiding the effects from monitors.
Evolutionary robotics
Authors: Bongard Josh C.
Published: April 2020

Taking a biologically inspired approach to the design of autonomous, adaptive machines.
Dynamic Synchronous/Asynchronous Replication
Authors: Natanzon Assaf , Bachmat Eitan
Published: April 2020

Online, remote, data replication is critical for today’s enterprise IT organization. Availability of data is key to the success of the organization. A few hours of downtime can cost from thousands to millions of dollars With increasing frequency, companies are instituting disaster recovery plans to ensure appropriate data availability in the event of a catastrophic failure or disaster that destroys a site (e.g. flood, fire, or earthquake).

Synchronous and asynchronous replication technologies have been available for a long period of time. Synchronous replication has the advantage of no data loss, but due to latency, synchronous replication is limited by distance and bandwidth. Asynchronous replication on the other hand has no distance limitation, but leads to some data loss which is proportional to the data lag. We present a novel method, implemented within EMC Recover-Point, which allows the system to dynamically move between these replication options without any disruption to the I/O path. As latency grows, the system will move from synchronous replication to semi-synchronous replication and then to snapshot shipping. It returns to synchronous replication as more bandwidth is available and latency allows.
DLIC
Authors: Gu Ji , Guo Hui , Ishihara Tohru
Published: April 2020

With the explosive proliferation of embedded systems, especially through countless portable devices and wireless equipment used, embedded systems have become indispensable to the modern society and people's life. Those devices are often battery driven. Therefore, low energy consumption in embedded processors is important and becomes critical in step with the system complexity. The on-chip instruction cache (I-cache) is usually the most energy-consuming component on the processor chip due to its large size and frequent access operations. To reduce such energy consumption, the existing loop cache approaches use a tiny decoded cache to filter the I-cache access and instruction decode activity for repeated loop iterations. However, such designs are effective for small and simple loops, and only suitable for DSP kernel-like applications. They are not effectual for many embedded applications where complex loops are common. In this article, we propose a decoded loop instruction cache (DLIC) that is small, hence energy efficient, yet can capture most loops, including large nested ones with branch executions, so that a significant amount of I-cache accesses and instruction decoding can be eradicated. The experiments on a set of embedded benchmarks show that our proposed DLIC scheme can reduce energy consumption by up to 87% as compared to normal cache-only design. On average, 66% energy can be saved on instruction fetching and decoding, while at a performance overhead of only 1.4%.
A reliability enhancement design under the flash translation layer for MLC-based flash-memory storage systems
Authors: Chang Yuan-Hao , Yang Ming-Chang , Kuo Tei-Wei , Hwang Ren-Hung
Published: April 2020

Although flash memory has gained very strong momentum in the storage market, the reliability of flash-memory chips has been dropped significantly in the past years. This article presents a reliability enhancement design under the flash management layer (i.e., flash translation layer) to address this concern so as to reduce the design complexity of flash-memory management software/firmware and to improve the maintainability and portability of existing and future products. In particular, a log-based write strategy with a hash-based caching policy is proposed to provide extra ECC redundancy and performance improvement. Strategies for bad block management are also presented. The failure rate of flash-memory storage systems is analyzed with the considerations of bit errors. The proposed design is later evaluated by a series of experiments based on realistic traces. It was shown that the proposed approach could significantly improve the reliability of flash memory with very limited system overheads.
A sound and complete abstraction for reasoning about parallel prefix sums
Authors: Chong Nathan , Donaldson Alastair F. , Ketema Jeroen
Published: April 2020

Prefix sums are key building blocks in the implementation of many concurrent software applications, and recently much work has gone into efficiently implementing prefix sums to run on massively parallel graphics processing units (GPUs). Because they lie at the heart of many GPU-accelerated applications, the correctness of prefix sum implementations is of prime importance.

We introduce a novel abstraction, the interval of summations, that allows scalable reasoning about implementations of prefix sums. We present this abstraction as a monoid, and prove a soundness and completeness result showing that a generic sequential prefix sum implementation is correct for an array of length $n$ if and only if it computes the correct result for a specific test case when instantiated with the interval of summations monoid. This allows correctness to be established by running a single test where the input and result require O(n lg(n)) space. This improves upon an existing result by Sheeran where the input requires O(n lg(n)) space and the result O(n
2
\lg(n)) space, and is more feasible for large
n
than a method by Voigtlaender that uses O(n) space for the input and result but requires running O(n
2
) tests. We then extend our abstraction and results to the context of data-parallel programs, developing an automated verification method for GPU implementations of prefix sums. Our method uses static verification to prove that a generic prefix sum implementation is data race-free, after which functional correctness of the implementation can be determined by running a single test case under the interval of summations abstraction.

We present an experimental evaluation using four different prefix sum algorithms, showing that our method is highly automatic, scales to large thread counts, and significantly outperforms Voigtlaender's method when applied to large arrays.
Verification column
Authors: Rungta Neha
Published: April 2020

In this issue of the SIGLOG newsletter, the technical column on verification presents an invited contribution on "Algorithmic Logic-Based Verification" by Arie Gurfinkel (Software Engineering Institute / Carnegie Mellon University), Temesghen Kahsai (NASA Ames / Carnegie Mellon University), and Jorge Navas (NASA Ames / SGT Inc.). The increasing number of programming languages and intermediate representations poses an obstacle in the development of a unified verification framework. The article presents a case for the use of Constrained Horn Clauses (CHC) as a universal representation for transition systems to overcome this obstacle. This article should be of special interest to the readers of this newsletter as CHCs have been used in various logic-based application domains, but are relatively new to the domain of verification. I would like to thank the authors for submitting the article.
The complexity of reachability in vector addition systems
Authors: Schmitz Sylvain
Published: April 2020

The program of the 30th Symposium on Logic in Computer Science held in 2015 in Kyoto included two contributions on the computational complexity of the
reachability problem
for vector addition systems: Blondin, Finkel, Göller, Haase, and McKenzie [2015] attacked the problem by providing the first tight complexity bounds in the case of dimension 2 systems with states, while Leroux and Schmitz [2015] proved the first complexity upper bound in the general case. The purpose of this column is to present the main ideas behind these two results, and more generally survey the current state of affairs.
Automata theory and higher-order model-checking
Authors: Walukiewicz Igor
Published: April 2020

In verification, an automata theoretic approach is by now a standard. In order to extend this approach to higher-order programs we need a good understanding of higher-order control flow, and for this semantics has the right tools. We present some results and methods of this subject between automata theory and semantics.
Ehrenfeucht, Vaught, and the decidability of the weak monadic theory of successor
Authors: Thomas Wolfgang
Published: April 2020

The decidability of the weak monadic theory of successor is usually considered as a consequence of the connection between monadic second-order logic and finite automata, as established around 1960 in papers of Büchi, Elgot, and Trakhtenbrot. However, there are several remarks and footnotes in papers of that time indicating that the result is also derivable from a theorem of A. Ehrenfeucht using an unpublished remark of R. L. Vaught. In the present note we review these hints and provide a proof along these lines. This simple argument is of methodological interest since it relies solely on first-order model theory and does not use finite automata.
Discovering Interesting Subpaths with Statistical Significance from Spatiotemporal Datasets
Authors: Xie Yiqun , Zhou Xun , Shekhar Shashi
Published: April 2020

Given a path in a spatial or temporal framework, we aim to find all contiguous subpaths that are both interesting (e.g., abrupt changes) and statistically significant (i.e., persistent trends rather than local fluctuations). Discovering interesting subpaths can provide meaningful information for a variety of domains including Earth science, environmental science, urban planning, and the like. Existing methods are limited to detecting individual points of interest along an input path but cannot find interesting subpaths. Our preliminary work provided a Subpath Enumeration and Pruning (SEP) algorithm to detect interesting subpaths of arbitrary length. However, SEP is not effective in avoiding detections that are random variations rather than meaningful trends, which hampers clear and proper interpretations of the results. In this article, we extend our previous work by proposing a significance testing framework to eliminate these random variations. To compute the statistical significance, we first show a baseline Monte-Carlo method based on our previous work and then propose a Dynamic Search-and-Prune (D-SAP) algorithm to improve its computational efficiency. Our experiments show that the significance testing can greatly suppress the noisy detections in the output and D-SAP can greatly reduce the execution time.
Transit Signal Priority Along a Signalized Arterial
Authors: Mishra Suman , Kattan Lina , Wirasinghe S. C.
Published: April 2020

This article develops a passenger-based priority for transit buses by balancing the trade-offs between the benefits at major streets and delays on side streets. A rule-based Transit Signal Priority (TSP) is set to assign priority to scheduled-based transit vehicles based on: their schedule adherence, passenger occupancy, and passengers waiting at downstream stops. The minimum number of bus passengers required to receive priority is obtained using deterministic queueing theory for the two cases of green extension and red truncation. VISSIM simulation software is used to evaluate the performance of the developed TSP approach, comparing it with: existing, unconditional, and no-TSP scenarios. This evaluation assessed performance measures for major streets, crossing streets, and the network level. The simulation demonstrated that a passenger-based TSP results in a significant decrease in travel time and side-street delay, compared to existing priority measures (buses will receive priority once every three minutes) on the corridor.
Market Clearing–based Dynamic Multi-agent Task Allocation
Authors: Nelke Sofia Amador , Okamoto Steven , Zivan Roie
Published: April 2020

Realistic multi-agent team applications often feature dynamic environments with soft deadlines that penalize late execution of tasks. This puts a premium on quickly allocating tasks to agents. However, when such problems include temporal and spatial constraints that require tasks to be executed sequentially by agents, they are NP-hard, and thus are commonly solved using general and specifically designed incomplete heuristic algorithms.

We propose FMC_TA, a novel such incomplete task allocation algorithm that allows tasks to be easily sequenced to yield high-quality solutions. FMC_TA first finds allocations that are fair (envy-free), balancing the load and sharing important tasks among agents, and efficient (Pareto optimal) in a simplified version of the problem. It computes such allocations in polynomial or pseudo-polynomial time (centrally or distributedly, respectively) using a Fisher market with agents as buyers and tasks as goods. It then heuristically schedules the allocations, taking into account inter-agent constraints on shared tasks.

We empirically compare our algorithm to state-of-the-art incomplete methods, both centralized and distributed, on law enforcement problems inspired by real police logs. We present a novel formalization of the law enforcement problem, which we use to perform our empirical study. The results show a clear advantage for FMC_TA in total utility and in measures in which law enforcement authorities measure their own performance. Besides problems with realistic properties, the algorithms were compared on synthetic problems in which we increased the size of different elements of the problem to investigate the algorithm’s behavior when the problem scales. The domination of the proposed algorithm was found to be consistent.
Transfer Learning with Dynamic Distribution Adaptation
Authors: Wang Jindong , Chen Yiqiang , Feng Wenjie , Yu Han , Huang Meiyu , Yang Qiang
Published: April 2020

Transfer learning aims to learn robust classifiers for the target domain by leveraging knowledge from a source domain. Since the source and the target domains are usually from different distributions, existing methods mainly focus on adapting the cross-domain marginal or conditional distributions. However, in real applications, the marginal and conditional distributions usually have different contributions to the domain discrepancy. Existing methods fail to quantitatively evaluate the different importance of these two distributions, which will result in unsatisfactory transfer performance. In this article, we propose a novel concept called Dynamic Distribution Adaptation (DDA), which is capable of quantitatively evaluating the relative importance of each distribution. DDA can be easily incorporated into the framework of structural risk minimization to solve transfer learning problems. On the basis of DDA, we propose two novel learning algorithms: (1) Manifold Dynamic Distribution Adaptation (MDDA) for traditional transfer learning, and (2) Dynamic Distribution Adaptation Network (DDAN) for deep transfer learning. Extensive experiments demonstrate that MDDA and DDAN significantly improve the transfer learning performance and set up a strong baseline over the latest deep and adversarial methods on digits recognition, sentiment analysis, and image classification. More importantly, it is shown that marginal and conditional distributions have different contributions to the domain divergence, and our DDA is able to provide good quantitative evaluation of their relative importance, which leads to better performance. We believe this observation can be helpful for future research in transfer learning.
DHPA
Authors: Pan Menghai , Huang Weixiao , Li Yanhua , Zhou Xun , Liu Zhenming , Song Rui , Lu Hui , Tian Zhihong , Luo Jun
Published: April 2020

Many real-world human behaviors can be modeled and characterized as sequential decision-making processes, such as a taxi driver’s choices of working regions and times. Each driver possesses unique preferences on the sequential choices over time and improves the driver’s working efficiency. Understanding the dynamics of such preferences helps accelerate the learning process of taxi drivers. Prior works on taxi operation management mostly focus on finding optimal driving strategies or routes, lacking in-depth analysis on what the drivers learned during the process and how they affect the performance of the driver. In this work, we make the first attempt to establish Dynamic Human Preference Analytics. We inversely learn the taxi drivers’ preferences from data and characterize the dynamics of such preferences over time. We extract two types of features (i.e., profile features and habit features) to model the decision space of drivers. Then through inverse reinforcement learning, we learn the preferences of drivers with respect to these features. The results illustrate that self-improving drivers tend to keep adjusting their preferences to habit features to increase their earning efficiency while keeping the preferences to profile features invariant. However, experienced drivers have stable preferences over time. The exploring drivers tend to randomly adjust the preferences over time.
FROST
Authors: Wang Meng , Li Hui , Cui Jiangtao , Bhowmick Sourav S. , Liu Ping
Published: April 2020

The facility relocation (FR) problem, which aims to optimize the placement of facilities to accommodate the changes of users’ locations, has a broad spectrum of applications. Despite the significant progress made by existing solutions to the FR problem, they all assume each user is stationary and represented as a single point. Unfortunately, in reality, objects (e.g., people, animals) are mobile. For example, a car-sharing user picks up a vehicle from a station close to where he or she is currently located. Consequently, these efforts may fail to identify a superior solution to the FR problem. In this article, for the first time, we take into account the movement history of users and introduce a novel FR problem, called
motion-fr
, to address the preceding limitation. Specifically, we present a framework called
frost
to address it.
frost
comprises two exact algorithms:
index based
and
index free
. The former is designed to address the scenario when facilities and objects are known
a priori
, whereas the latter solves the
motion-fr
problem by jettisoning this assumption. Further, we extend the index-based algorithm to solve the general
k
-
motion-fr
problem, which aims to relocate
k
inferior facilities. We devise an approximate solution due to NP-hardness of the problem. Experimental study over both real-world and synthetic datasets demonstrates the superiority of our framework in comparison to state-of-the-art FR techniques in efficiency and effectiveness.
Privacy- and Context-aware Release of Trajectory Data
Authors: Naghizade Elham , Kulik Lars , Tanin Egemen , Bailey James
Published: April 2020

The availability of large-scale spatio-temporal datasets along with the advancements in analytical models and tools have created a unique opportunity to create valuable insights into managing key areas of society from transportation and urban planning to epidemiology and natural disasters management. This has encouraged the practice of releasing/publishing trajectory datasets among data owners. However, an ill-informed publication of such rich datasets may have serious privacy implications for individuals. Balancing privacy and utility, as a major goal in the data exchange process, is challenging due to the richness of spatio-temporal datasets. In this article, we focus on an individual’s stops as the most sensitive part of the trajectory and aim to preserve them through spatio-temporal perturbation. We model a trajectory as a sequence of
stops
and
moves
and propose an efficient algorithm that either substitutes sensitive stop points of a trajectory with moves from the same trajectory or introduces a minimal detour if no safe Point of Interest (POI) can be found on the same route. This hinders the amount of unnecessary distortion, since the footprint of the original trajectory is preserved as much as possible. Our experiments shows that our method balances user privacy and data utility: It protects privacy through preventing an adversary from making inferences about sensitive stops while maintaining a high level of similarity to the original dataset.
Unified Generative Adversarial Networks for Multiple-Choice Oriented Machine Comprehension
Authors: Liu Zhuang , Xiao Keli , Jin Bo , Huang Kaiyu , Huang Degen , Zhang Yunxia
Published: April 2020

In this article, we address the multiple-choice machine comprehension (MC) problem in natural language processing. Existing approaches for MC are usually designed for general cases; however, we specially develop a novel method for solving the multiple-choice MC problem. We take the inspiration generative adversarial networks (GANs) and first propose an adversarial framework for multiple-choice oriented MC, named
McGAN
. Specifically, our approach is designed as a GAN-based method that unifies both generative and discriminative MC models. Working together, the generative model focuses on predicting relevant answer given a passage (text) and a question; the discriminative model focuses on predicting their relevancy given an answer-passage-question set. Based on the competition via adversarial training in a minimize-maximize game, the proposed method takes advantages from both models. To evaluate the performance, we test our McGAN model on three well-known datasets for multiple-choice MC. Our results show that McGAN can achieve a significant increase in accuracy compared to existing models based on all three datasets, and it consistently outperforms all tested baselines, including state-of-the-art techniques.
Review—Conducting Polymer-Based Binders for Lithium-Ion Batteries and Beyond
Authors: Nguyen Van At , Kuss Christian
Published: April 2020

In the search for active Lithium-ion battery materials with ever-increasing energy density, the limits of conventional auxiliary materials, such as binders and conducting additives are being tested. Binders adhere to active substances and current collectors, yielding an interconnected electrode structure that ensures mechanical integrity during the (de-)lithiation process. Even though the battery binder only accounts for a fraction of battery weight and cost, it is a bottleneck technology in the deployment of high energy density active materials that experience significant volume variation and side-reactions. This review paper discusses research on alternative binders derived from conducting polymers (CPs). The use of CPs in binders enables mechanically flexible electronic contacts with the active material with the goal of accommodating larger volume changes within the electrode. Following a summary of the reasoning behind the use of CP-based binders, their rational design is reviewed, including novel composite syntheses and chemical modifications. A new class of multifunctional CP-based binders exhibits promising properties such as high electronic conductivity, the ability for aqueous processing, and efficient binding that tackle the limiting features of traditional binders. The practical application of these binders in Li-ion batteries and beyond is summarized, yielding an outline of current achievements, and a discussion of remaining knowledge gaps and possible future development of such binders.