bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacterial Surface Spreading Is More Efficient on Nematically Aligned Polysaccharide Substrates
Authors: Lemon David J. , Schutzman Derek A. , Garza Anthony G.
Published: January 2018

Biofilm-forming bacteria typically deposit layers of polysaccharides on the surfaces they inhabit; hence, polysaccharides are their immediate environment on such surfaces. Previously, we showed that many biofilm-forming bacteria preferentially spread in the direction of aligned and densely packed polysaccharide fibers in compressed substrates, a behavior we referred to as polymertropism. This arrangement of polysaccharide fibers is likely to be similar to that found in the “slime” trails deposited by many biofilm-forming bacteria and would explain previous observations that bacteria tend to follow these trails of polysaccharides. Here, we show that groups of cells or flares spread more rapidly on substrates containing aligned and densely packed polysaccharide fibers. Flares also persist longer, tend to hold their trajectories parallel to the long axes of polysaccharide fibers longer, and ultimately show an increase in displacement away from their origin. On the basis of these findings and others, we propose a model for polymertropism. Namely, we suggest that the packing of the aligned polymers increases the efficiency of surface spreading in the direction of the polymer's long axes; therefore, bacteria tend to spread more rapidly in this direction. Additional work suggests that bacteria can leverage polymertropism, and presumably more efficient surface spreading, for a survival advantage. In particular, when two bacterial species were placed in close proximity and in competition with each other, the ability of one species to move rapidly and directly away from the other by utilizing the aligned polymers of compressed agar substrates led to a clear survival benefit.

IMPORTANCE
The directed movement of bacteria on compressed substrates was first described in the 1940s and referred to as elasticotaxis (R. Y. Stanier, J Bacteriol 44:405–412, 1942). More recently, this behavior was referred to as polymertropism, as it seems to be a response to the nematic alignment and tight packing of polymers in the substrate (D. J. Lemon, X. Yang, P. Srivastava, Y. Y. Luk, A. G. Garza, Sci Rep 7:7643, 2017,
https://doi.org/10.1038/s41598-017-07486-0
). The data presented here suggest that bacteria are more efficient at surface spreading when the polymers in the substrate are arranged in this manner. These data also suggest that bacteria can leverage polymertropism, and presumably more efficient surface spreading, for a survival advantage. Namely, one bacterial species was able to use its strong polymertropism response to escape from and survive competition with another species that normally outcompetes it.
Influenza C and D Viruses Package Eight Organized Ribonucleoprotein Complexes
Authors: Nakatsu Sumiho , Murakami Shin , Shindo Keiko , Horimoto Taisuke , Sagara Hiroshi , Noda Takeshi , Kawaoka Yoshihiro
Published: January 2018

Influenza A and B viruses have eight-segmented, single-stranded, negative-sense RNA genomes, whereas influenza C and D viruses have seven-segmented genomes. Each genomic RNA segment exists in the form of a ribonucleoprotein complex (RNP) in association with nucleoproteins and an RNA-dependent RNA polymerase in virions. Influenza D virus was recently isolated from swine and cattle, but its morphology is not fully studied. Here, we examined the morphological characteristics of D/bovine/Yamagata/10710/2016 (D/Yamagata) and C/Ann Arbor/50 (C/AA), focusing on RNPs packaged within the virions. By scanning transmission electron microscopic tomography, we found that more than 70% of D/Yamagata and C/AA virions packaged eight RNPs arranged in the “1+7” pattern as observed in influenza A and B viruses, even though type C and D virus genomes are segmented into only seven segments. These results imply that influenza viruses generally package eight RNPs arranged in the “1+7” pattern regardless of the number of RNA segments in their genome.

IMPORTANCE
The genomes of influenza A and B viruses are segmented into eight segments of negative-sense RNA, and those of influenza C and D viruses are segmented into seven segments. For progeny virions to be infectious, each virion needs to package all of their genomic segments. Several studies support the conclusion that influenza A and B viruses selectively package eight distinct genomic RNA segments; however, the packaging of influenza C and D viruses, which possess seven segmented genomes, is less understood. By using electron microscopy, we showed that influenza C and D viruses package eight RNA segments just as influenza A and B viruses do. These results suggest that influenza viruses prefer to package eight RNA segments within virions independent of the number of genome segments.
Infection and Replication of Influenza Virus at the Ocular Surface
Authors: Creager Hannah M. , Kumar Amrita , Zeng Hui , Maines Taronna R. , Tumpey Terrence M. , Belser Jessica A.
Published: January 2018

Although influenza viruses typically cause respiratory tract disease, some viruses, particularly those with an H7 hemagglutinin, have been isolated from the eyes of conjunctivitis cases. Previous work has shown that isolates of multiple subtypes from both ocular and respiratory infections are capable of replication in human
ex vivo
ocular tissues and corneal or conjunctival cell monolayers, leaving the determinants of ocular tropism unclear. Here, we evaluated the effect of several variables on tropism for ocular cells cultured
in vitro
and examined the potential effect of the tear film on viral infectivity. All viruses tested were able to replicate in primary human corneal epithelial cell monolayers subjected to aerosol inoculation. The temperature at which cells were cultured postinoculation minimally affected infectivity. Replication efficiency, in contrast, was reduced at 33°C relative to that at 37°C, and this effect was slightly greater for the conjunctivitis isolates than for the respiratory ones. With the exception of a seasonal H3N2 virus, the subset of viruses studied in multilayer corneal tissue constructs also replicated productively after either aerosol or liquid inoculation. Human tears significantly inhibited the hemagglutination of both ocular and nonocular isolates, but the effect on viral infectivity was more variable, with tears reducing the infectivity of nonocular isolates more than ocular isolates. These data suggest that most influenza viruses may be capable of establishing infection if they reach the surface of ocular cells but that this is more likely for ocular-tropic viruses, as they are better able to maintain their infectivity during passage through the tear film.

IMPORTANCE
The potential spread of zoonotic influenza viruses to humans represents an important threat to public health. Unfortunately, despite the importance of cellular and tissue tropism to pathogenesis, determinants of influenza virus tropism have yet to be fully elucidated. Here, we sought to identify factors that limit the ability of most influenza viruses to cause ocular infection. Although ocular symptoms in humans caused by avian influenza viruses tend to be relatively mild, these infections are concerning due to the potential of the ocular surface to serve as a portal of entry for viruses that go on to establish respiratory infections. Furthermore, a better understanding of the factors that influence infection and replication in this noncanonical site may point toward novel determinants of tropism in the respiratory tract.
Timing Is Everything
Authors: Schang Luis M.
Published: January 2018

N. Drayman et al. in their recent article (mBio 8:e01612-17, 2017,
https://doi.org/10.1128/mBio.01612-17
) have used dynamic proteomics and machine learning to show that the cell cycle state of any individual cell affects the outcome of a productive herpes simplex virus 1 (HSV-1) infection. Cells infected from early G
1
through S were most permissive for expression of genes from the HSV-1 genome, whereas cells infected in late G
2
to mitosis were much less so. Most of the infected cells that underwent mitosis became permanently nonpermissive for HSV-1 gene expression afterward. The cell cycle stage accounted for 60% of the success of infection, and cell density and motility accounted for most of the rest. To successfully reactivate, HSV-1 must express its genes in neurons and cells of the spinosum and granulosum epidermis strata. These cells are permanently in the cell cycle stages most permissive for HSV-1 gene expression, and none reenters mitosis, thus maximizing the efficiency of a successful HSV-1 reactivation before the adaptive immunity can control it.
Multiple Inhibitory Factors Act in the Late Phase of HIV-1 Replication: a Systematic Review of the Literature
Authors: Gélinas Jean-François , Gill Deborah R. , Hyde Stephen C.
Published: January 2018

The use of lentiviral vectors for therapeutic purposes has shown promising results in clinical trials. The ability to produce a clinical-grade vector at high yields remains a critical issue. One possible obstacle could be cellular factors known to inhibit human immunodeficiency virus (HIV). To date, five HIV restriction factors have been identified, although it is likely that more factors are involved in the complex HIV-cell interaction. Inhibitory factors that have an adverse effect but do not abolish virus production are much less well described. Therefore, a gap exists in the knowledge of inhibitory factors acting late in the HIV life cycle (from transcription to infection of a new cell), which are relevant to the lentiviral vector production process. The objective was to review the HIV literature to identify cellular factors previously implicated as inhibitors of the late stages of lentivirus production. A search for publications was conducted on MEDLINE via the PubMed interface, using the keyword sequence “HIV restriction factor” or “HIV restriction” or “inhibit HIV” or “repress HIV” or “restrict HIV” or “suppress HIV” or “block HIV,” with a publication date up to 31 December 2016. Cited papers from the identified records were investigated, and additional database searches were performed. A total of 260 candidate inhibitory factors were identified. These factors have been identified in the literature as having a negative impact on HIV replication. This study identified hundreds of candidate inhibitory factors for which the impact of modulating their expression in lentiviral vector production could be beneficial.
Nuclear, Cytosolic, and Surface-Localized Poly(A)-Binding Proteins of Plasmodium yoelii
Authors: Minns Allen M. , Hart Kevin J. , Subramanian Suriyasri , Hafenstein Susan , Lindner Scott E.
Published: January 2018

Malaria remains one of the great global health problems. The parasite that causes malaria (
Plasmodium
genus) relies upon exquisite control of its transmission between vertebrate hosts and mosquitoes. One crucial way that it does so is by proactively producing mRNAs needed to establish the new infection but by silencing and storing them until they are needed. One key protein in this process of translational repression in model eukaryotes is poly(A)-binding protein (PABP). Here we have shown that
Plasmodium yoelii
utilizes both a nuclear PABP and a cytosolic PABP, both of which bind specifically to polyadenylated RNA sequences. Moreover, we find that the cytosolic PABP forms chains
in vitro
, consistent with its appreciated role in coating the poly(A) tails of mRNA. Finally, we have also verified that, surprisingly, the cytosolic PABP is found on the surface of
Plasmodium
sporozoites. Taking the data together, we propose that
Plasmodium
utilizes a more metazoan-like strategy for RNA metabolism using specialized PABPs.
Identification of Head and Neck Cancer Subtypes Based on Human Papillomavirus Presence and E2F-Regulated Gene Expression
Authors: Johnson Molly E. , Cantalupo Paul G. , Pipas James M.
Published: January 2018

Cancer is a complex disease that can be caused by a multitude of factors. HNSCC is complicated because some of these cancers are clearly associated with HPV, while others have no viral involvement. Determining the pathways that are commonly altered in both types of HNSCC, as well as those that are unique to viral and nonviral tumors, is important for a basic understanding of how these cancers arise and progress and critical to the development of targeted therapies. In this work, we show that all HPV-associated tumors have increased expression of E2F target genes, indicating that the tumor suppressor function of Rb is blocked. Importantly, Rb is also inhibited in a subset of nonviral tumors, suggesting that mutations present in these cancers mimic the action of the HPV E6 and E7 oncogenes.
NORMATIVE VALUES FOR CERVICAL LORDOSIS: A CROSS SECTIONAL STUDY
Authors: Midde Ajaya Kumar , Panigrahi Manas , Kumari Manoranjitha , Tedla Jaya Shanker
Published: January 2018

Purpose: The aim of the current study is to obtain normative Cobb’s angle values for the cervical lordosis based on the cervical sagittal radiograph and to study the effects of age, height, weight, BMI on the cervical lordosis in Indian population. Method: After taking the written consent from 44 healthy subjects without any neck problems, the radiographs of these subjects were taken for digitalization into the picture archiving and communication system (PACS). Among 44 subjects, 33 were males and 11 were females with age groups ranging between 30 and 60 years were included. Subjects with any congenital or developmental spinal problems, any history of cervical spine-related health issues were excluded from the study. The Results: The demographic characteristics are being assessed for final results, the calculated Cobb’s angle [Formula: see text] is [Formula: see text] and the correlation of Cobb’s angle with demographic characteristics has also been made. The [Formula: see text]-values obtained for studied variables, age versus Cobb’s angle, height versus Cobb’s angle, weight versus angle, BMI versus Cobb’s angle were [Formula: see text]0.155, 0.083, 0.105 and 0.016, respectively. And the corresponding probability values were 0.314, 0.588, 0.496 and 0.913. Conclusion: The normal lordosis value of the cervical spine of Indian population has been evaluated, the [Formula: see text] are [Formula: see text] and there is no correlation of Cobb’s angle on any studied variables.
Stochastic inclusions and set-valued stochastic equations driven by a two-parameter Wiener process
Authors: Michta Mariusz , Świa̧tek Kamil Łukasz
Published: January 2018

In the paper we study properties of solutions to stochastic differential inclusions and set-valued stochastic differential equations driven by a two-parameter Wiener process. We establish new connections between their solutions. We prove that attainable sets of solutions to such inclusions are subsets of values of multivalued solutions of associated set-valued stochastic equations. Next we show that every solution to stochastic inclusion is a continuous selection of a multivalued solution of an associated set-valued stochastic equation. Additionally we establish other properties of such solutions. The results obtained in the paper extends results dealing with this topic known both in deterministic and stochastic cases.
Geometric Configuration Effects on Nonlinear Seismic Behavior of Concrete Gravity Dam
Authors: Ansari Md. Imteyaz , Saqib Mohd , Agarwal Pankaj
Published: January 2018

The effects of geometric configuration on the seismic vulnerability of concrete gravity dam are discussed in the present study. The seismic vulnerability of concrete gravity dams has been represented through fragility curves obtained through incremental dynamic analyses by considering their nonlinear dynamic behavior. Five different geometries of concrete gravity dams are considered and fragility analyses are carried out on the basis of Incremental Dynamic Analyses. The effect of smoothening of re-entrant corners in the geometry of high concrete gravity dam is also presented as a possible solution.
OPTIMAL INVESTMENT AND OPTIMAL ADDITIONAL VOLUNTARY CONTRIBUTION RATE OF A DC PENSION FUND IN A JUMP-DIFFUSION ENVIRONMENT
Authors: NKEKI CHARLES I.
Published: January 2018

This paper considers an optimal investment and an optimal additional contribution rate of a pension plan member (PPM) who faces both diffusion and jump risks in a defined contribution (DC) pension plan. We put into consideration three background risks which include interest rate, investment and salary risks. The stock prices, interest rate and salary process of a PPM are allowed to follow a jump-diffusion process. A PPM is expected to make two kind of contributions: compulsory and additional voluntary contributions. The compulsory one is a fixed proportion of a PPM's salary and the additional one is voluntary which is time and interest rate dependent. The aims of the investor is to determine the optimal investment and optimal contribution rate in a jump-diffusion environment. In order to obtain the optimal investment and optimal contribution rate, the resulting wealth process was transformed into Hamilton–Jacobi–Bellman equation by the method of dynamic programming. As a result, the optimal investment and optimal contribution rate of a PPM were obtained. Furthermore, some empirical analyses were conducted and results obtained. We found that the optimal investment ultimately depend on stocks diffusion and jump risks, interest rate and salary risks, optimal contribution rate and the salary process. The contribution rate of a PPM was found to depend on the investment strategies, salary process and interest rate risks, salary and its growth rate and CRRA coefficient. We also found that the contribution rate depends inversely on the salary process of a PPM over time.
Complexity of Propositional Logics in Team Semantic
Authors: Hannula Miika , Kontinen Juha , Virtema Jonni , Vollmer Heribert
Published: January 2018

We classify the computational complexity of the satisfiability, validity, and model-checking problems for propositional independence, inclusion, and team logic. Our main result shows that the satisfiability and validity problems for propositional team logic are complete for alternating exponential-time with polynomially many alternations.
Completeness of Flat Coalgebraic Fixpoint Logics
Authors: Schröder Lutz , Venema Yde
Published: January 2018

Modal fixpoint logics traditionally play a central role in computer science, in particular in artificial intelligence and concurrency. The μ-calculus and its relatives are among the most expressive logics of this type. However, popular fixpoint logics tend to trade expressivity for simplicity and readability and in fact often live within the single variable fragment of the μ-calculus. The family of such
flat
fixpoint logics includes, e.g., Linear Temporal Logic (LTL), Computation Tree Logic (CTL), and the logic of common knowledge. Extending this notion to the generic semantic framework of
coalgebraic logic
enables covering a wide range of logics beyond the standard μ-calculus including, e.g., flat fragments of the graded μ-calculus and the alternating-time μ-calculus (such as alternating-time temporal logic), as well as probabilistic and monotone fixpoint logics. We give a generic proof of completeness of the Kozen-Park axiomatization for such flat coalgebraic fixpoint logics.
The noninvasive simultaneous measurement of tissue oxygenation and microvascular hemodynamics during incremental handgrip exercise
Authors: Hammer Shane M. , Alexander Andrew M. , Didier Kaylin D. , Smith Joshua R. , Caldwell Jacob T. , Sutterfield Shelbi L. , Ade Carl J. , Barstow Thomas J.
Published: January 2018

Limb blood flow increases linearly with exercise intensity; however, invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We tested the hypotheses that 1) brachial artery blood flow (Q̇BA) would increase with increasing exercise intensity until task failure, 2) blood flow index of the flexor digitorum superficialis (BFIFDS) measured noninvasively via diffuse correlation spectroscopy would plateau at a submaximal work rate, and 3) muscle oxygenation characteristics (total-[heme], deoxy-[heme], and percentage saturation) measured noninvasively with near-infrared spectroscopy would demonstrate a plateau at a similar work rate as BFIFDS. Sixteen subjects (23.3 ± 3.9 yr, 170.8 ± 1.9 cm, 72.8 ± 3.4 kg) participated in this study. Peak power (Ppeak) was determined for each subject (1.8 ± 0.4 W) via an incremental handgrip exercise test. Q̇BA, BFIFDS, total-[heme], deoxy-[heme], and percentage saturation were measured during each stage of the exercise test. On a subsequent testing day, muscle activation measurements of the FDS (RMSFDS) were collected during each stage of an identical incremental handgrip exercise test via electromyography from a subset of subjects ( n = 7). Q̇BA increased with exercise intensity until the final work rate transition ( P < 0.05). No increases in BFIFDS or muscle oxygenation characteristics were observed at exercise intensities greater than 51.5 ± 22.9% of Ppeak. No submaximal plateau in RMSFDS was observed. Whereas muscle activation of the FDS increased until task failure, noninvasively measured indices of perfusive and diffusive muscle microvascular oxygen delivery demonstrated submaximal plateaus.

NEW & NOTEWORTHY Invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We demonstrate that indices of perfusive and diffusive microvascular oxygen transport to skeletal muscle, measured completely noninvasively, plateau at submaximal work rates during incremental exercise, even though limb blood flow and muscle recruitment continued to increase.
Fiber type-specific analysis of AMPK isoforms in human skeletal muscle: advancement in methods via capillary nanoimmunoassay
Authors: Tobias Irene S. , Lazauskas Kara K. , Arevalo Jose A. , Bagley James R. , Brown Lee E. , Galpin Andrew J.
Published: January 2018

Human skeletal muscle is a heterogeneous mixture of multiple fiber types (FT). Unfortunately, present methods for FT-specific study are constrained by limits of protein detection in single-fiber samples. These limitations beget compensatory resource-intensive procedures, ultimately dissuading investigators from pursuing FT-specific research. Additionally, previous studies neglected hybrid FT, confining their analyses to only pure FT. Here we present novel methods of protein detection across a wider spectrum of human skeletal muscle FT using fully automated capillary nanoimmunoassay (CNIA) technology. CNIA allowed a ~20-fold-lower limit of 5′-AMP-activated protein kinase (AMPK) detection compared with Western blotting. We then performed FT-specific assessment of AMPK expression as a proof of concept. Individual human muscle fibers were mechanically isolated, dissolved, and myosin heavy chain (MHC) fiber typed via SDS-PAGE. Single-fiber samples were combined in pairs and grouped into MHC I, MHC I/IIa, MHC IIa, and MHC IIa/IIx for expression analysis of AMPK isoforms α1, α2, β1, β2, γ2, and γ3 with a tubulin loading control. Significant FT-specific differences were found for α2 (1.7-fold higher in MHC IIa and MHC IIa/IIx vs. others), γ2 (2.5-fold higher in MHC IIa vs. others), and γ3 (2-fold higher in MHC IIa and 4-fold higher in MHC IIa/IIx vs. others). Development of a protocol that combines the efficient and sensitive CNIA technology with comprehensive SDS-PAGE fiber typing marks an important advancement in FT-specific research because it allows more precise study of the molecular mechanisms governing metabolism, adaptation, and regulation in human muscle.

NEW & NOTEWORTHY We demonstrate the viability of applying capillary nanoimmunoassay technology to the study of fiber type-specific protein analysis in human muscle fibers. This novel technique enables a ~20-fold-lower limit of protein detection compared with traditional Western blotting methods. Combined with SDS-PAGE methods of fiber typing, we apply this technique to compare 5′-AMP-activated protein kinase isoform expression in myosin heavy chain (MHC) I, MHC I/IIa, MHC IIa, and MHC IIa/IIx fiber types.
Intermittent hypoxia in utero damages postnatal growth and cardiovascular function in rats
Authors: Chen Ling , Zadi Zahra Heidari , Zhang Jin , Scharf Steven M. , Pae Eung-Kwon
Published: January 2018

Obstructive sleep apnea (OSA) is common in pregnancy and may compromise fetal and even postnatal development. We developed an animal model to determine if maternal OSA could have lasting effects in offspring. Pregnant Sprague-Dawley rats were exposed to reduced ambient O2 from 21 to 4–5%, approximately once per minute [chronic intermittent hypoxia (CIH)] for 8 h/day during gestation days 3–19. Similarly handled animals exposed to ambient air served as controls (HC). Offspring were studied for body growth and cardiovascular function for 8 postnatal weeks. Compared with HC, prenatal CIH led to growth restriction, indicated by smaller body weight and tibial length, and higher arterial blood pressure in both male and female offspring. Compared with same-sex HC, CIH males showed abdominal obesity (greater ratio of abdominal fat weight to body weight or tibial length), left ventricular (LV) hypertrophy (greater heart weight-to-tibial length ratio and LV posterior wall diastolic thickness), elevated LV contractility (increases in LV ejection fraction, end-systolic pressure-volume relations, and preload recruitable stroke work), elevated LV and arterial stiffness (increased end-diastolic pressure-volume relationship and arterial elasticity), and LV oxidative stress (greater lipid peroxide content). Compared with female CIH offspring, male CIH offspring had more profound changes in blood pressure (BP), cardiac function, myocardial lipid peroxidase (LPO) content, and abdominal adiposity. Rodent prenatal CIH exposure, mimicking human maternal OSA, exerts detrimental morphological and cardiovascular effects on developing offspring; the model may provide useful insights of OSA effects in humans.

NEW & NOTEWORTHY Obstructive sleep apnea is common in human pregnancy. Following maternal exposure to chronic intermittent hypoxia, a hallmark of sleep apnea, both sexes of rat offspring showed growth retardation, with males being more vulnerable to hypertension and dysfunctional left ventricular changes. This model is useful to study detrimental effects of maternal obstructive sleep apnea on developing offspring in humans.
Predictive monitoring of actions, EEG recordings in virtual reality
Authors: Ozkan Duru G. , Pezzetta Rachele
Published: January 2018

Error-related negativity (ERN) is a signal that is associated with error detection. Joch and colleagues (Joch M, Hegele M, Maurer H, Müller H, Maurer LK. J Neurophysiol 118: 486–495, 2017) successfully separated the ERN as a response to online prediction error from feedback updates. We discuss the role of ERN in action and suggest insights from virtual reality techniques; we consider the potential benefit of self-evaluation in determining the mechanisms of ERN amplitude; finally, we review the oscillatory activity that has been claimed to accompany ERN.
Workflow Scheduling Using Hybrid GA‐PSO Algorithm in Cloud Computing
Authors: Manasrah Ahmad M. , Ba Ali Hanan
Published: January 2018

Cloud computing environment provides several on‐demand services and resource sharing for clients. Business processes are managed using the workflow technology over the cloud, which represents one of the challenges in using the resources in an efficient manner due to the dependencies between the tasks. In this paper, a Hybrid GA‐PSO algorithm is proposed to allocate tasks to the resources efficiently. The Hybrid GA‐PSO algorithm aims to reduce the makespan and the cost and balance the load of the dependent tasks over the heterogonous resources in cloud computing environments. The experiment results show that the GA‐PSO algorithm decreases the total execution time of the workflow tasks, in comparison with GA, PSO, HSGA, WSGA, and MTCT algorithms. Furthermore, it reduces the execution cost. In addition, it improves the load balancing of the workflow application over the available resources. Finally, the obtained results also proved that the proposed algorithm converges to optimal solutions faster and with higher quality compared to other algorithms.
Incorporating Contagion in Portfolio Credit Risk Models Using Network Theory
Authors: Anagnostou Ioannis , Sourabh Sumit , Kandhai Drona
Published: January 2018

Portfolio credit risk models estimate the range of potential losses due to defaults or deteriorations in credit quality. Most of these models perceive default correlation as fully captured by the dependence on a set of common underlying risk factors. In light of empirical evidence, the ability of such a conditional independence framework to accommodate for the occasional default clustering has been questioned repeatedly. Thus, financial institutions have relied on stressed correlations or alternative copulas with more extreme tail dependence. In this paper, we propose a different remedy—augmenting systematic risk factors with a contagious default mechanism which affects the entire universe of credits. We construct credit stress propagation networks and calibrate contagion parameters for infectious defaults. The resulting framework is implemented on synthetic test portfolios wherein the contagion effect is shown to have a significant impact on the tails of the loss distributions.
EE‐MRP: Energy‐Efficient Multistage Routing Protocol for Wireless Sensor Networks
Authors: Khan Muhammad Kamran , Shiraz Muhammad , Zrar Ghafoor Kayhan , Khan Suleman , Safaa Sadiq Ali , Ahmed Ghufran
Published: January 2018

Wireless sensor networks (WSNs) have captivated substantial attention from both industrial and academic research in the last few years. The major factor behind the research efforts in that field is their vast range of applications which include surveillance systems, military operations, health care, environment event monitoring, and human safety. However, sensor nodes are low potential and energy constrained devices; therefore, energy‐efficient routing protocol is the foremost concern. In this paper, an energy‐efficient routing protocol for wireless sensor networks is proposed. Our protocol consists of a routing algorithm for the transmission of data, cluster head selection algorithm, and a scheme for the formation of clusters. On the basis of energy analysis of the existing routing protocols, a multistage data transmission mechanism is proposed. An efficient cluster head selection algorithm is adopted and unnecessary frequency of reclustering is exterminated. Static clustering is used for efficient selection of cluster heads. The performance and energy efficiency of our proposed routing protocol are assessed by the comparison of the existing routing protocols on a simulation platform. On the basis of simulation results, it is observed that our proposed routing protocol (EE‐MRP) has performed well in terms of overall network lifetime, throughput, and energy efficiency.
Long Noncoding RNA pancEts-1 Promotes Neuroblastoma Progression through hnRNPK-Mediated β-Catenin Stabilization
Authors: Li Dan , Wang Xiaojing , Mei Hong , Fang Erhu , Ye Lin , Song Huajie , Yang Feng , Li Huanhuan , Huang Kai , Zheng Liduan , Tong Qiangsong
Published: January 2018

Long noncoding RNAs (lncRNA) play essential roles in tumor progression. However, the functions of lncRNAs in the tumorigenesis and aggressiveness of neuroblastoma still remain to be determined. Here, we report the identification of lncRNA pancEts-1 as a novel driver of neuroblastoma progression by using a public microarray dataset. LncRNA pancEts-1 promoted the growth, invasion, and metastasis of neuroblastoma cells in vitro and in vivo. Mechanistically, pancEts-1 bound to hnRNPK to facilitate its physical interaction with β-catenin, whereas hnRNPK stabilized the β-catenin by inhibiting proteasome-mediated degradation, resulting in transcriptional alteration of target genes associated with neuroblastoma progression. Both pancEts-1 and hnRNPK were upregulated in clinical neuroblastoma tissues, and were associated with unfavorable outcome of patients. Overall, our results define an oncogenic role of pancEts-1 in neuroblastoma progression through hnRNPK-mediated β-catenin stabilization, with potential implications for the clinical therapeutics of neuroblastoma.

Significance: These findings reveal the oncogenic functions of a long noncoding RNA in neuroblastoma progression, offering a potential target for clinical therapeutics. Cancer Res; 78(5); 1169–83. ©2018 AACR.
Night Shift Work Increases the Risks of Multiple Primary Cancers in Women: A Systematic Review and Meta-analysis of 61 Articles
Authors: Yuan Xia , Zhu Chenjing , Wang Manni , Mo Fei , Du Wei , Ma Xuelei
Published: January 2018

A growing number of studies have examined associations between night shift work and the risks of common cancers among women, with varying conclusions. We did a meta-analysis to identify whether long-term night shift work increased the risks of common cancers in women. We enrolled 61 articles involving 114,628 cases and 3,909,152 participants from Europe, North America, Asia, and Australia. Risk estimates were performed with a random-effect model or a fixed-effect model. Subgroup analyses and meta-regression analyses about breast cancer were conducted to explore possible sources of heterogeneity. In addition, we carried out a dose–response analysis to quantitatively estimate the accumulative effect of night shift work on the risk of breast cancer. A positive relationship was revealed between long-term night shift work and the risks of breast [OR = 1.316; 95% confidence interval (CI), 1.196–1.448], digestive system (OR = 1.177; 95% CI, 1.065–1.301), and skin cancer (OR = 1.408; 95% CI, 1.024–1.934). For every 5 years of night shift work, the risk of breast cancer in women was increased by 3.3% (OR = 1.033; 95% CI, 1.012–1.056). Concerning the group of nurses, long-term night shift work presented potential carcinogenic effect in breast cancer (OR = 1.577; 95% CI, 1.235–2.014), digestive system cancer (OR = 1.350; 95% CI, 1.030–1.770), and lung cancer (OR = 1.280; 95% CI, 1.070–1.531). This systematic review confirmed the positive association between night shift work and the risks of several common cancers in women. We identified that cancer risk of women increased with accumulating years of night shift work, which might help establish and implement effective measures to protect female night shifters. Cancer Epidemiol Biomarkers Prev; 27(1); 25–40. ©2018 AACR.
Collapsing the Tumor Ecosystem: Preventing Adaptive Response to Treatment by Inhibiting Transcription
Authors: Carugo Alessandro , Draetta Giulio F.
Published: January 2018

Summary: Adaptation and resistance to treatment are the results of a multitude of (epi)genetic events unmasked or directly triggered by therapies targeting the genetic driver(s) of a dominant cell population within a tumor mass. Rusan and colleagues report that drug-tolerant cells are sensitive to THZ1, a dual CDK7/12 inhibitor, which, by impairing the transcriptional machinery, can prevent cellular rewiring to survive therapeutic attack. Cancer Discov; 8(1); 17–9. ©2018 AACR.

See related article by Rusan et al., p. 59.
The Local Defender and Functional Mediator: Gut Microbiome
Authors: Yang Hang , Duan Zhijun
Published: January 2018

Background: The gut microbiome has been developing and making adaption all the time, which is consistent with their host from the initial colonization at birth or earlier. Emerging evidence is showing that dysbiosis is involved in various diseases associated with immune, metabolism, infection, nervous system, social behaviors, and psychopathology, etc., maybe via modulating gut barrier, microbiome-gut-brain axis, or some metabolites like short-chain fatty acids (SCFAs). Summary: In the review, we will conclude the recent researches related to the influence of microbiome on local structure, function, regulation, metabolism of gut, and systematic modulation to the host, as well as some affective factors such as diet or antibiotics. Key Messages: It is a reasonable hypothesis that the balance of bioactive factors or cells and the opposites such as the regulatory T/helper T17 balance and interleukin (IL)-10/IL-17 balance plays a vital role in homeostasis of immunity system. Meanwhile, the link between gut microbiome and immune system via microbiota-derived metabolite SCFAs involved in multi-function of the host locally and systematically has been revealed. We hope to contribute to the microbiome-targeted treatment and prevention of some diseases.
Differential Expression and Remodeling of Transient Outward Potassium Currents in Human Left Ventricles
Authors: Johnson Eric K. , Springer Steven J. , Wang Wei , Dranoff Edward J. , Zhang Yan , Kanter Evelyn M. , Yamada Kathryn A. , Nerbonne Jeanne M.
Published: January 2018

Background

Myocardial, transient, outward currents,
I
to
, have been shown to play pivotal roles in action potential (AP) repolarization and remodeling in animal models. The properties and contribution of
I
to
to left ventricular (LV) repolarization in the human heart, however, are poorly defined.

Methods and Results

Whole-cell, voltage-clamp recordings, acquired at physiological (35°C to 37°C) temperatures, from myocytes isolated from the LV of nonfailing human hearts identified 2 distinct transient currents,
I
to,fast
(
I
to,f
) and
I
to,slow
(
I
to,s
), with significantly (
P
<0.0001) different rates of recovery from inactivation and pharmacological sensitives:
I
to,f
recovers in ≈10 ms, 100× faster than
I
to,s
, and is selectively blocked by the Kv4 channel toxin, SNX-482. Current-clamp experiments revealed regional differences in AP waveforms, notably a phase 1 notch in LV subepicardial myocytes. Dynamic clamp-mediated addition/removal of modeled human ventricular
I
to,f
, resulted in hyperpolarization or depolarization, respectively, of the notch potential, whereas slowing the rate of
I
to,f
inactivation resulted in AP collapse. AP-clamp experiments demonstrated that changes in notch potentials modified the time course and amplitudes of voltage-gated Ca
2+
currents,
I
Ca
. In failing LV subepicardial myocytes,
I
to,f
was reduced and
I
to,s
was increased, notch and plateau potentials were depolarized (
P
<0.0001) and AP durations were prolonged (
P
<0.001).

Conclusions

I
to,f
and
I
to,s
are differentially expressed in nonfailing human LV, contributing to regional heterogeneities in AP waveforms.
I
to,f
regulates notch and plateau potentials and modulates the time course and amplitude of
I
Ca
. Slowing
I
to,f
inactivation results in dramatic AP shortening. Remodeling of
I
to,f
in failing human LV subepicardial myocytes attenuates transmural differences in AP waveforms.
Pulse Wave Velocity Predicts the Progression of Blood Pressure and Development of Hypertension in Young Adults
Authors: Koivistoinen Teemu , Lyytikäinen Leo-Pekka , Aatola Heikki , Luukkaala Tiina , Juonala Markus , Viikari Jorma , Lehtimäki Terho , Raitakari Olli T. , Kähönen Mika , Hutri-Kähönen Nina
Published: January 2018

The aim of the present study was to examine whether pulse wave velocity (PWV) predicts the progression of blood pressure and the development of hypertension in young adults. In addition, we studied whether PWV improves the risk prediction of incident hypertension beyond traditional cardiovascular risk factors. Systolic and diastolic blood pressures were measured in 2007 and 2011 for 1449 Finnish adults (aged 30–45 years). In addition, PWV and other cardiovascular risk factors were measured in 2007. The association between PWV (in 2007) and blood pressure (in 2011) was studied in the whole population (n=1449) and in a normotensive subpopulation (n=1183). The ability of PWV measured in 2007 to predict incident hypertension in 2011 was investigated in the subpopulation (n=1183). PWV measured in 2007 was directly and independently associated with systolic and diastolic blood pressures measured in 2011 (
P
<0.001 for both). PWV measured in 2007 was also an independent predictor of incident hypertension in 2011 (odds ratio, 1.96 per 1-SDincrease; 95% confidence interval, 1.51–2.57;
P
<0.001). The extended prediction model (including PWV) improved the incident hypertension risk prediction beyond traditional cardiovascular risk factors, the area under receiver operating characteristics curve being 0.833 versus 0.809 (
P
=0.040), and the continuous net reclassification improvement 59.4% (
P
<0.001). These findings suggest that PWV predicts the progression of blood pressure and could provide a valuable tool in hypertension risk prediction in young adults.
Climate Change and the Politics of Military Bases
Authors: Colgan Jeff D.
Published: January 2018

How does climate change affect the politics of military bases? The United States alone has hundreds of overseas bases that require continuous coordination with host governments. I argue that climate change can create knock-on environmental problems associated with a base’s infrastructure or waste. Those knock-on problems create a mix of subnational, international, and transnational political contestation that raises the political costs of overseas bases and could even rupture an international relationship. I probe the plausibility of the theoretical framework using new evidence from Greenland. Between 1953 and 1967, the US Army maintained secret bases in Greenland as precursors for a nuclear ballistic missile complex. The bases were eventually abandoned, leaving considerable waste behind. Climate change is now poised to remobilize these pollutants into the surface water, creating a risk for human settlements. The case could be the proverbial canary in the coal mine for future politics surrounding overseas military bases.
Toward Environmental Democracy? Procedural Environmental Rights and Environmental Justice
Authors: Gellers Joshua C. , Jeffords Chris
Published: January 2018

The global trend toward adopting environmental rights within national constitutions has been largely regarded as a positive development for both human rights and the natural environment. The impact of constitutional environmental rights, however, has yet to be systematically assessed using empirical data. In particular, expanding procedural environmental rights—legal provisions relating to access to information, participation, and justice in environmental matters—provides fertile ground for analyzing how environmental rights directly interface with conditions necessary for a functioning democracy. To understand the extent to which these provisions deliver on their lofty aspirations, we conducted a quantitative analysis to assess the relationship between procedural environmental rights and environmental justice, while also controlling for the extent of democracy within a country. The results suggest that states with procedural environmental rights are more likely than nonadopting states to facilitate attaining environmental justice, especially as it relates to access to information.
Contralateral Delay Activity Tracks Fluctuations in Working Memory Performance
Authors: Adam Kirsten C. S. , Robison Matthew K. , Vogel Edward K.
Published: January 2018

Neural measures of working memory storage, such as the contralateral delay activity (CDA), are powerful tools in working memory research. CDA amplitude is sensitive to working memory load, reaches an asymptote at known behavioral limits, and predicts individual differences in capacity. An open question, however, is whether neural measures of load also track trial-by-trial fluctuations in performance. Here, we used a whole-report working memory task to test the relationship between CDA amplitude and working memory performance. If working memory failures are due to decision-based errors and retrieval failures, CDA amplitude would not differentiate good and poor performance trials when load is held constant. If failures arise during storage, then CDA amplitude should track both working memory load and trial-by-trial performance. As expected, CDA amplitude tracked load (Experiment 1), reaching an asymptote at three items. In Experiment 2, we tracked fluctuations in trial-by-trial performance. CDA amplitude was larger (more negative) for high-performance trials compared with low-performance trials, suggesting that fluctuations in performance were related to the successful storage of items. During working memory failures, participants oriented their attention to the correct side of the screen (lateralized P1) and maintained covert attention to the correct side during the delay period (lateralized alpha power suppression). Despite the preservation of attentional orienting, we found impairments consistent with an executive attention theory of individual differences in working memory capacity; fluctuations in executive control (indexed by pretrial frontal theta power) may be to blame for storage failures.
A new pygmy squid, Idiosepius hallami n. sp. (Cephalopoda: Idiosepiidae)
from eastern Australia and elevation of the southern endemic ‘notoides’ clade to a new genus, Xipholeptos n. gen.
Authors: REID AMANDA L. , STRUGNELL JAN M.
Published: January 2018

A new species of pygmy squid, Idiosepius hallami n. sp., is described from eastern Australia. It differs from I. notoides Berry, 1921 and I. pygmaeus Steenstrup, 1881 (also found in Australian waters) in a number of traits, including the number of club suckers, shape of the funnel-mantle locking apparatus and the modification of the male hectocotylus. Mitochondrial DNA markers (12S rRNA, 16S rRNA and cytochrome c oxidase subunit 1) indicate that it is also distinct on a molecular level. The new Australian species is also recognised as the taxon from Stradbroke I., Queensland for which the entire mitochondrial genome has been sequenced (Hall et al. 2014). Idiosepius hallami n. sp. is compared with all nominal Idiosepius Steenstrup, 1881 and a current summary of Idiosepius systematics is provided as a basis for future studies. Based on our analyses, we propose the elevation of the ‘notoides’ clade to the new genus Xipholeptos n. gen., retaining Idiosepius as the genetic epithet for all other nominal idiosepiids. This is supported by: monophyly of the two lineages based on molecular data sets, the level of sequence divergence between these lineages, and morphological differences. The ‘notoides’ clade is endemic to southern Australia and its basal phylogenetic position suggests that the family may have originated in the Australasian region. Idiosepiids are found in seagrass beds and among mangroves—among the most threatened ecosystems in the world.