bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Hybrid Plasmid Carrying Multiple Antimicrobial Resistance and Virulence Genes in Salmonella enterica Serovar Dublin
Authors: Mangat Chand S. , Bekal Sadjia , Irwin Rebecca J. , Mulvey Michael R.
Published: March 2017

Virulence plasmids and antibiotic resistance plasmids are usually maintained separately in
Salmonella
spp.; however, we report an instance of a hybrid plasmid (pN13-01125) in
Salmonella enterica
serovar Dublin. Review of the complete sequence of the 172,265-bp plasmid suggests that pN13-01125 is comprised of the previously described pSDVr and pSH696_135 plasmids and that the mechanism of hybridization likely involves IS
6
(IS
26
) insertion sequence elements. The plasmid has a low conjugation frequency, confers resistance to six classes of antimicrobials, and contains a complete
spv
virulence operon.
Adaptive Upregulation of Clumping Factor A (ClfA) by Staphylococcus aureus in the Obese, Type 2 Diabetic Host Mediates Increased Virulence
Authors: Farnsworth Christopher W. , Schott Eric M. , Jensen Sarah E. , Zukoski Jacob , Benvie Abigail M. , Refaai Majed A. , Kates Stephen L. , Schwarz Edward M. , Zuscik Michael J. , Gill Steven R. , Mooney Robert A.
Published: March 2017

Obesity and associated type 2 diabetes (T2D) are important risk factors for infection following orthopedic implant surgery.
Staphylococcus aureus
, the most common pathogen in bone infections, adapts to multiple environments to survive and evade host immune responses. Whether adaptation of
S. aureus
to the unique environment of the obese/T2D host accounts for its increased virulence and persistence in this population is unknown. Thus, we assessed implant-associated osteomyelitis in normal versus high-fat-diet obese/T2D mice and found that
S. aureus
infection was more severe, including increases in bone abscesses relative to nondiabetic controls.
S. aureus
isolated from bone of obese/T2D mice displayed marked upregulation of four adhesion genes (
clfA
,
clfB
,
bbp
, and
sdrC
), all with binding affinity for fibrin(ogen). Immunostaining of infected bone revealed increased fibrin deposition surrounding bacterial abscesses in obese/T2D mice.
In vitro
coagulation assays demonstrated a hypercoagulable state in obese/T2D mice that was comparable to that of diabetic patients.
S. aureus
with an inactivating mutation in clumping factor A (
clfA
) showed a reduction in bone infection severity that eliminated the effect of obesity/T2D, while infections in control mice were unchanged. In infected mice that overexpress plasminogen activator inhibitor-1 (PAI-1),
S. aureus
clfA
expression and fibrin-encapsulated abscess communities in bone were also increased, further linking fibrin deposition to
S. aureus
expression of
clfA
and infection severity. Together, these results demonstrate an adaptation by
S. aureus
to obesity/T2D with increased expression of
clfA
that is associated with the hypercoagulable state of the host and increased virulence of
S. aureus
.
Optogenetic Module for Dichromatic Control of c-di-GMP Signaling
Authors: Ryu Min-Hyung , Fomicheva Anastasia , Moskvin Oleg V. , Gomelsky Mark
Published: March 2017

Many aspects of bacterial physiology and behavior, including motility, surface attachment, and the cell cycle, are controlled by cyclic di-GMP (c-di-GMP)-dependent signaling pathways on the scale of seconds to minutes. Interrogation of such processes in real time requires tools for introducing rapid and reversible changes in intracellular c-di-GMP levels. Inducing the expression of genes encoding c-di-GMP-synthetic (diguanylate cyclases) and -degrading (c-di-GMP phosphodiesterase) enzymes by chemicals may not provide adequate temporal control. In contrast, light-controlled diguanylate cyclases and phosphodiesterases can be quickly activated and inactivated. A red/near-infrared-light-regulated diguanylate cyclase, BphS, was engineered previously, yet a complementary light-activated c-di-GMP phosphodiesterase has been lacking. In search of such a phosphodiesterase, we investigated two homologous proteins from
Allochromatium vinosum
and
Magnetococcus marinus
, designated BldP, which contain C-terminal EAL-BLUF modules, where EAL is a c-di-GMP phosphodiesterase domain and BLUF is a blue light sensory domain. Characterization of the BldP proteins in
Escherichia coli
and
in vitro
showed that they possess light-activated c-di-GMP phosphodiesterase activities. Interestingly, light activation in both enzymes was dependent on oxygen levels. The truncated EAL-BLUF fragment from
A. vinosum
BldP lacked phosphodiesterase activity, whereas a similar fragment from
M. marinus
BldP, designated EB1, possessed such activity that was highly (>30-fold) upregulated by light. Following light withdrawal, EB1 reverted to the inactive ground state with a half-life of ∼6 min. Therefore, the blue-light-activated phosphodiesterase EB1 can be used in combination with the red/near-infrared-light-regulated diguanylate cyclase BphS for the bidirectional regulation of c-di-GMP-dependent processes in
E. coli
as well as other bacterial and nonbacterial cells.

IMPORTANCE
Regulation of motility, attachment to surfaces, the cell cycle, and other bacterial processes controlled by the c-di-GMP signaling pathways occur at a fast (seconds-to-minutes) pace. Interrogation of these processes at high temporal and spatial resolution using chemicals is difficult or impossible, while optogenetic approaches may prove useful. We identified and characterized a robust, blue-light-activated c-di-GMP phosphodiesterase (hydrolase) that complements a previously engineered red/near-infrared-light-regulated diguanylate cyclase (c-di-GMP synthase). These two enzymes form a dichromatic module for manipulating intracellular c-di-GMP levels in bacterial and nonbacterial cells.
The Pseudomonas aeruginosa Two-Component Regulator AlgR Directly Activates
rsmA
Expression in a Phosphorylation-Independent Manner
Authors: Stacey Sean D. , Williams Danielle A. , Pritchett Christopher L.
Published: March 2017

Pseudomonas aeruginosa
is an important pathogen of the immunocompromised, causing both acute and chronic infections. In cystic fibrosis (CF) patients,
P. aeruginosa
causes chronic disease. The impressive sensory network of
P. aeruginosa
allows the bacterium to sense and respond to a variety of stimuli found in diverse environments. Transcriptional regulators, including alternative sigma factors and response regulators, integrate signals changing gene expression, allowing
P. aeruginosa
to cause infection. The two-component transcriptional regulator AlgR is important in
P. aeruginosa
pathogenesis in both acute and chronic infections. In chronic infections, AlgR and the alternative sigma factor AlgU activate the genes responsible for alginate production. Previous work demonstrated that AlgU controls
rsmA
expression. RsmA is a posttranscriptional regulator that is antagonized by two small RNAs, RsmY and RsmZ. In this work, we demonstrate that AlgR directly activates
rsmA
expression from the same promoter as AlgU. In addition, phosphorylation was not necessary for AlgR activation of
rsmA
using
algR
and
algZ
mutant strains. AlgU and AlgR appear to affect the antagonizing small RNAs
rsmY
and
rsmZ
indirectly. RsmA was active in a
mucA22
mutant strain using leader fusions of two RsmA targets,
tssA1
and
hcnA
. AlgU and AlgR were necessary for posttranscriptional regulation of
tssA1
and
hcnA
. Altogether, our work demonstrates that the alginate regulators AlgU and AlgR are important in the control of the RsmA posttranscriptional regulatory system. These findings suggest that RsmA plays an unknown role in mucoid strains due to AlgU and AlgR activities.

IMPORTANCE
P. aeruginosa
infections are difficult to treat and frequently cause significant mortality in CF patients. Understanding the mechanisms of persistence is important. Our work has demonstrated that the alginate regulatory system also significantly impacts the posttranscriptional regulator system RsmA/Y/Z. We demonstrate that AlgR directly activates
rsmA
expression, and this impacts the RsmA regulon. This leads to the possibility that the RsmA/Y/Z system plays a role in helping
P. aeruginosa
persist during chronic infection. In addition, this furthers our understanding of the reach of the alginate regulators AlgU and AlgR.
Contributions of the N- and C-Terminal Domains of Initiation Factor 3 to Its Functions in the Fidelity of Initiation and Antiassociation of the Ribosomal Subunits
Authors: Ayyub Shreya Ahana , Dobriyal Divya , Varshney Umesh
Published: March 2017

Initiation factor 3 (IF3) is one of the three conserved prokaryotic translation initiation factors essential for protein synthesis and cellular survival. Bacterial IF3 is composed of a conserved architecture of globular N- and C-terminal domains (NTD and CTD) joined by a linker region. IF3 is a ribosome antiassociation factor which also modulates selection of start codon and initiator tRNA. All the functions of IF3 have been attributed to its CTD by
in vitro
studies. However, the
in vivo
relevance of these findings has not been investigated. By generating complete and partial IF3 (
infC
) knockouts in
Escherichia coli
and by complementation analyses using various deletion constructs, we show that while the CTD is essential for
E. coli
survival, the NTD is not. Polysome profiles reaffirm that CTD alone can bind to the 30S ribosomal subunit and carry out the ribosome antiassociation function. Importantly, in the absence of the NTD, bacterial growth is compromised, indicating a role for the NTD in the fitness of cellular growth. Using reporter assays for
in vivo
initiation, we show that the NTD plays a crucial role in the fidelity function of IF3 by avoiding (i) initiation from non-AUG codons and (ii) initiation by initiator tRNAs lacking the three highly conserved consecutive GC pairs (in the anticodon stem) known to function in concert with IF3.

IMPORTANCE
Initiation factor 3 regulates the fidelity of eubacterial translation initiation by ensuring the formation of an initiation complex with an mRNA bearing a canonical start codon and with an initiator tRNA at the ribosomal P site. Additionally, IF3 prevents premature association of the 50S ribosomal subunit with the 30S preinitiation complex. The significance of our work in
Escherichia coli
is in demonstrating that while the C-terminal domain alone sustains
E. coli
for its growth, the N-terminal domain adds to the fidelity of initiation of protein synthesis and to the fitness of the bacterial growth.
LptO (PG0027) Is Required for Lipid A 1-Phosphatase Activity in Porphyromonas gingivalis W50
Authors: Rangarajan Minnie , Aduse-Opoku Joseph , Hashim Ahmed , McPhail Graham , Luklinska Zofia , Haurat M. Florencia , Feldman Mario F. , Curtis Michael A.
Published: March 2017

Porphyromonas gingivalis
produces outer membrane vesicles (OMVs) rich in virulence factors, including cysteine proteases and A-LPS, one of the two lipopolysaccharides (LPSs) produced by this organism. Previous studies had suggested that A-LPS and PG0027, an outer membrane (OM) protein, may be involved in OMV formation. Their roles in this process were examined by using W50 parent and the Δ
PG0027
mutant strains. Inactivation of
PG0027
caused a reduction in the yield of OMVs. Lipid A from cells and OMVs of
P. gingivalis
W50 and the Δ
PG0027
mutant strains were analyzed by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Lipid A from W50 cells contained bis-P-pentaacyl, mono-P-pentaacyl, mono-P-tetraacyl, non-P-pentaacyl, and non-P-tetraacyl species, whereas lipid A from Δ
PG0027
mutant cells contained only phosphorylated species; nonphosphorylated species were absent. MALDI-TOF/TOF tandem MS of mono-P-pentaacyl (
m
/
z
1,688) and mono-P-tetraacyl (
m
/
z
1,448) lipid A from Δ
PG0027
showed that both contained lipid A 1-phosphate, suggesting that the Δ
PG0027
mutant strain lacked lipid A 1-phosphatase activity. The total phosphatase activities in the W50 and the Δ
PG0027
mutant strains were similar, whereas the phosphatase activity in the periplasm of the Δ
PG0027
mutant was lower than that in W50, supporting a role for PG0027 in lipid A dephosphorylation. W50 OMVs were enriched in A-LPS, and its lipid A did not contain nonphosphorylated species, whereas lipid A from the Δ
PG0027
mutant (OMVs and cells) contained similar species. Thus, OMVs in
P. gingivalis
are apparently formed in regions of the OM enriched in A-LPS devoid of nonphosphorylated lipid A. Conversely, dephosphorylation of lipid A through a PG0027-dependent process is required for optimal formation of OMVs. Hence, the relative proportions of nonphosphorylated and phosphorylated lipid A appear to be crucial for OMV formation in this organism.

IMPORTANCE
Gram-negative bacteria produce outer membrane vesicles (OMVs) by “blebbing” of the outer membrane (OM). OMVs can be used offensively as delivery systems for virulence factors and defensively to aid in the colonization of a host and in the survival of the bacterium in hostile environments. Earlier studies using the oral anaerobe
Porphyromonas gingivalis
as a model organism to study the mechanism of OMV formation suggested that the OM protein PG0027 and one of the two lipopolysaccharides (LPSs) synthesized by this organism, namely, A-LPS, played important roles in OMV formation. We suggest a novel mechanism of OMV formation in
P. gingivalis
involving dephosphorylation of lipid A of A-LPS controlled/regulated by PG0027, which causes destabilization of the OM, resulting in blebbing and generation of OMVs.
Near death by milk of magnesia
Authors: Alaini Ahmed , Roldan Carlos A , Servilla Karen , Colombo Elizabeth Sage
Published: March 2017

We report a case of hypermagnesemia associated with the use of milk of magnesia in a male patient with end-stage renal disease. After experiencing nausea and vomiting, he developed severe bradycardia and then asystole. Resuscitation efforts were successful; however, he developed atrial fibrillation with severe widening of the QRS and diffuse ST elevation, hypothermia, hypotension and apnoea requiring intubation. Initial diagnoses included ST-elevation myocardial infarction, cardiogenic and/or septic shock and hyperkalaemia. However, serum magnesium was later found to be >4.1 mmol/L (equivalent to >10 mg/dL). He underwent haemodialysis (HD) to remove serum magnesium with remarkable overall improvement. Severe hypermagnesemia can manifest with severe bradycardia and asystole, shock, hypothermia and respiratory failure and can mimic acute coronary syndromes complicated with cardiogenic shock or septic shock. Therefore, clinicians should be aware of this life-threatening condition in patients with significant renal dysfunction. Timely treatment with HD is highly effective and lifesaving.
Carcinosarcoma of the bladder following local schistosomiasis infection
Authors: Srougi Victor , Gallucci Fabio P , Mattedi Romulo L , Srougi Miguel
Published: March 2017

A young patient from central Africa presented acute renal insufficiency due to extrinsic compression of the distal ureters by a pelvic mass. After initial medical management, a biopsy revealed poorly differentiated bladder cancer andSchistosoma haematobiumeggs embedded in the bladder wall. The initial workup showed evidence of locoregional disease. Radical cystectomy with an incontinent urinary diversion was performed with no complications. Carcinosarcoma of the bladder was diagnosed by pathological analysis of the surgical specimen. After a short follow-up, the patient was readmitted presenting with lung and bone metastases. At 60 days after diagnosis, he died of respiratory insufficiency caused by pulmonary metastatic disease.
RCT of the effect of berryfruit polyphenolic cultivar extract in mild steroid-naive asthma: a cross-over, placebo-controlled study
Authors: Power Sharon , Williams Mathew , Semprini Alex , Munro Claire , Caswell-Smith Rachel , Pilcher Janine , Holliday Mark , Fingleton James , Harper Jacquie , Hurst Roger , Weatherall Mark , Beasley Richard , Braithwaite Irene
Published: March 2017

Objective

There is preclinical evidence that consumption of berryfruit extract may reduce chronic airways inflammation and modify airway remodelling in allergen-induced models of lung inflammation. We investigated the effect of berryfruit extract on the fractional expired nitric oxide (FeNO), a biomarker of eosinophilic airways inflammation, in adults with steroid-naïve asthma.

Design

Randomised placebo-controlled cross-over double-blind trial.

Setting

Single-centre community-based trial.

Participants

28 steroid-naïve mild asthmatics with Feno>40 ppb, of whom 25 completed both study interventions.

Interventions

Participants were randomised to receive, according to the cross-over design, 100 mg berryfruit polyphenolic extract (BFPE) or placebo for 4 weeks, with a 4-week washout period between the interventions.

Primary outcome measure

The primary outcome variable was FeNO at 4 weeks, analysed by a mixed linear model, with a random effect for participant and baseline FeNo as a covariate.

Results

The mean (SD) natural logarithm transformed (ln) FeNO after 4 weeks of treatment for the BFPE and placebo groups was 4.28 (0.47) and 4.22 (0.47), respectively. The paired change from baseline mean (SD) BFPE minus placebo ln FeNO was −0.03 (0.39), N=25. The mixed linear model estimate, with baseline covariate adjustment, difference in ln FeNO, was −0.002 (95% CI −0.15 to 0.14), p=0.98. This is equivalent to a ratio of geometric mean FeNO of 1.0 (95% CI 0.86 to 1.15).

Conclusions

In steroid-naïve participants with mild asthma and elevated FeNO, there was no effect of BFPE on FeNO, a biomarker of eosinophilic airways inflammation. Caution is required in the extrapolation of apparent benefit in murine models of lung eosinophilia to clinical efficacy in patients with asthma.

Trial registration number

ANZCTR:12613000451707; Results.
Innovative public–private partnership to target subsidised antimalarials: a study protocol for a cluster randomised controlled trial to evaluate a community intervention in Western Kenya
Authors: Laktabai Jeremiah , Lesser Adriane , Platt Alyssa , Maffioli Elisa , Mohanan Manoj , Menya Diana , Prudhomme O'Meara Wendy , Turner Elizabeth L
Published: March 2017

Introduction

There are concerns of inappropriate use of subsidised antimalarials due to the large number of fevers treated in the informal sector with minimal access to diagnostic testing. Targeting antimalarial subsidies to confirmed malaria cases can lead to appropriate, effective therapy. There is evidence that community health volunteers (CHVs) can be trained to safely and correctly use rapid diagnostic tests (RDTs). This study seeks to evaluate the public health impact of targeted antimalarial subsidies delivered through a partnership between CHVs and the private retail sector.

Methods and analysis

We are conducting a stratified cluster-randomised controlled trial in Western Kenya where 32 community units were randomly assigned to the intervention or control (usual care) arm. In the intervention arm, CHVs offer free RDT testing to febrile individuals and, conditional on a positive test result, a voucher to purchase a WHO-qualified artemisinin combination therapy (ACT) at a reduced fixed price in the retail sector.

Study outcomes in individuals with a febrile illness in the previous 4 weeks will be ascertained through population-based cross-sectional household surveys at four time points: baseline, 6, 12 and 18 months postbaseline. The primary outcome is the proportion of fevers that receives a malaria test from any source (CHV or health facility). The main secondary outcome is the proportion of ACTs used by people with a malaria-positive test. Other secondary outcomes include: the proportion of ACTs used by people without a test and adherence to test results.

Ethics and dissemination

The protocol has been approved by the National Institutes of Health, the Moi University School of Medicine Institutional Research and Ethics Committee and the Duke University Medical Center Institutional Review Board. Findings will be reported on clinicalstrials.gov, in peer-reviewed publications and through stakeholder meetings including those with the Kenyan Ministry of Health.

Trial registration number

Pre-results,NCT02461628.
Effect of alcohol consumption and psychosocial stressors on preterm and small-for-gestational-age births in HIV-infected women in South Africa: a cohort study
Authors: Sania Ayesha , Brittain Kirsty , Phillips Tamsin K , Zerbe Allison , Ronan Agnes , Myer Landon , Abrams Elaine J
Published: March 2017

Objectives

Psychosocial stressors such as depression and stress, intimate partner violence (IPV) and alcohol use have been linked to preterm and small-for-gestational-age (SGA) births in general populations. The prevalence of psychosocial stressors and alcohol abuse is high in many HIV-infected (HIV+) populations. Our objective was to evaluate the effects of psychosocial stressors and alcohol abuse on birth outcomes in HIV-infected women.

Methods

Antenatal depression and non-specific psychological distress, periconception IPV and alcohol consumption were measured during the second trimester among HIV+ women initiating antiretroviral treatment with efavirenz + emtricitibine + tenofovir in Cape Town, South Africa. Log binomial regression models were used to estimate the risk ratios (RR) and 95% CIs of the effects of psychosocial stressors and periconception alcohol consumption on birth outcomes: SGA (birth weight <10th centile for gestational age) and preterm (<37 weeks) births.

Results

Of the 571 mother–infant pairs, 26% of women reported hazardous alcohol consumption (Alcohol Use Disorders Identification Test-C score ≥3) periconception periods, 11% reported depressive symptoms, 7% reported non-specific psychological distress and 15% reported experiencing physical or psychological IPV. 14% of infants were born preterm and 12% were SGA. Infants born to women reporting hazardous drinking were twice (adjusted RR 2.00 (95% CI 1.13 to 3.54)) as likely to be SGA compared with women reporting low alcohol intake. Alcohol consumption did not have a significant effect on the incidence of preterm birth. Depressive symptoms, non-specific psychological distress, physical and psychological IPV did not increase the risk of SGA or preterm birth significantly.

Conclusions

The observed elevated risk of SGA births associated with periconception alcohol consumption underscores the urgent need to reduce alcohol consumption among women of childbearing age. Interventions targeting modifiable risk factors of adverse birth outcomes need to be integrated into HIV prevention and maternal child health programmes to improve the long-term health of HIV-exposed children.

Trial registration number

NCT01933477; Pre-results.
What are the measures that can be used to assess performance during in situ Paediatric Emergency Medicine Simulation?
Authors: Mann Jennifer Amanda , Roland Damian
Published: March 2017

Background

Paediatric in situ simulation within emergency departments is growing in popularity as an approach for improving multidisciplinary team working, enabling clinical skills development and exploring the importance of human factors in the clinical setting. However, measuring the success of such programmes is often through participant feedback of satisfaction and not measures of performance, which makes it difficult to assess whether such programmes lead to improvements in clinical behaviour.

Objective

To identify the measures that can be used to assess performance during in situ paediatric emergency medicine simulations.

Study selection

A literature search of EMBASE, ERIC and MEDLINE was performed using the key terms (Paediatrics and Emergency and Simulation.) MeSH and subheadings were used to ensure all possible variations of the key terms were included within the search.

Findings

The search revealed 607 articles, with 16 articles meeting inclusion criteria. Three themes of evaluation strategy were identified—the use of feedback forms (56% n=9/16), performance evaluation methods (63% n=10/16) or other strategies (25% n=4/16), which included provider comfort scores, latent safety threat identification and episodes of suboptimal care and their causation.

Conclusions

The most frequently used method of assessment in paediatric emergency department simulation are performance evaluation methods. None of the studies in this area have looked at patient level outcomes and this is therefore an area which should be explored in the future.
What causes a small increase in radiographic progression in rheumatoid arthritis patients tapering TNF inhibitors?
Authors: Bouman Chantal A M , den Broeder Alfons A , van der Maas Aatke , van den Hoogen Frank H J , Landewé Robert B M , van Herwaarden Noortje
Published: March 2017

Objective

In a randomised controlled trial investigating tapering of TNF inhibitors (TNFi) compared with usual care (UC) in rheumatoid arthritis patients, minimal radiographic progression was more frequent in patients who attempted tapering. Possible explanations include higher incidence of flaring, higher mean disease activity or lower TNFi use.

Methods

18 months data from the DRESS study were used. Change in Sharp-van der Heijde (ΔSvdH) score (linear regression) and proportion of patients with >0.5 ΔSvdH (logistic regression) were used as outcomes. The cumulative incidence and number of short-lived and major flares per patient, mean time-weighted disease activity (MTW-DAS28-CRP) and TNFi use were used as independent variables. Regression models were performed stratified per study group and corrected for possible confounders.

Results

175 of 180 patients had 18-month data available. The mean ΔSvdH were 0.75 and 0.15 units with 37 of 116 (32%) and 9 of 59 (15%) patients exceeding 0.5 points in the tapering and UC group, respectively (both p<0.05). MTW-DAS28-CRP, but not incidence or number of short-lived or major flares, or TNFi use, was independently associated with the mean progression score, but only in the tapering group. Additional analyses on DAS28-CRP subcomponents showed that this was mainly caused by MTW swollen joint count. No confounders were identified.

Conclusions

Radiographic progression was associated with higher MTW-DAS28-CRP (and especially swollen joint count), but only in patients who tapered TNFi. This finding stresses the importance of maintaining disease activity as low as possible in patients in whom TNFi is tapered and to check for radiographic progression regularly.

Trial registration number

NTR 3216; Post-results.
Malnutrition or frailty? Overlap and evidence gaps in the diagnosis and treatment of frailty and malnutrition
Authors: Laur Celia V. , McNicholl Tara , Valaitis Renata , Keller Heather H.
Published: March 2017

There is increasing awareness of the detrimental health impact of frailty on older adults and of the high prevalence of malnutrition in this segment of the population. Experts in these 2 arenas need to be cognizant of the overlap in constructs, diagnosis, and treatment of frailty and malnutrition. There is a lack of consensus regarding the definition of malnutrition and how it should be assessed. While there is consensus on the definition of frailty, there is no agreement on how it should be measured. Separate assessment tools exist for both malnutrition and frailty; however, there is intersection between concepts and measures. This narrative review highlights some of the intersections within these screening/assessment tools, including weight loss/decreased body mass, functional capacity, and weakness (handgrip strength). The potential for identification of a minimal set of objective measures to identify, or at least consider risk for both conditions, is proposed. Frailty and malnutrition have also been shown to result in similar negative health outcomes and consequently common treatment strategies have been studied, including oral nutritional supplements. While many of the outcomes of treatment relate to both concepts of frailty and malnutrition, research questions are typically focused on the frailty concept, leading to possible gaps or missed opportunities in understanding the effect of complementary interventions on malnutrition. A better understanding of how these conditions overlap may improve treatment strategies for frail, malnourished, older adults.
When does hypoxia affect management performance of a fishery? A management strategy evaluation of Dungeness crab (Metacarcinus magister) fisheries in Hood Canal, Washington, USA
Authors: Froehlich Halley E. , Essington Timothy E. , McDonald P. Sean
Published: March 2017

Management strategies for fisheries typically do not account for environmental stressors, such as hypoxia (dissolved oxygen < 2 mg·L−1). Hypoxia can lead to shoaling of organisms into normoxic habitats, enhancing catchability, which could reduce the performance of fishery management strategies. Here, we conducted a management strategy evaluation of Dungeness crab (Metacarcinus magister) fisheries in Hood Canal, Washington, a seasonally hypoxic fjord in Puget Sound. Specifically, we asked whether the current management strategy was robust to hypoxia-induced catchability changes under alternative scenarios of illegal take, incidental capture mortality, and reproductive limitation. We find that the management strategy performed well to changes in catchability when illegal and incidental fishing mortality was low and fishing did not lead to reproductive limitation. However, the performance eroded markedly (reduced long-term catch and (or) population and higher catch variation) under the alternative scenarios. These findings underscore the benefit of applying an ecosystem approach to fisheries management because it identifies potential risks to management strategies in systems subject to environmental change.
Where is the Iapetus suture in northern New England? A study of the Ammonoosuc Volcanics, Bronson Hill terrane, New Hampshire1This article is one of a series of papers published in this CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.
Authors: Dorais Michael J. , Atkinson Miles , Kim Jon , West David P. , Kirby Gregory A.
Published: March 2017

The ∼470 Ma Ammonoosuc Volcanics of the Bronson Hill terrane of New Hampshire have back-arc basin basalt compositions. Major and trace element compositions compare favorably to coeval volcanic rocks in the Miramichi Highlands of New Brunswick and the Munsangan and Casco Bay volcanics of Maine, back-arc basin basalts of known peri-Gondwanan origins. Additionally, the Ammonoosuc Volcanics have Nd and Pb isotopic compositions indicative of peri-Gondwanan provenance. Thus, the Ammonoosuc Volcanics correlate with Middle Ordovician, peri-Gondwanan, Tetagouche–Exploits back-arc rocks of eastern New England and Maritime Canada. This correlation indicates that the Red Indian Line, the principle Iapetus suture, lies along the western margin of the Bronson Hill terrane. However, the younger (∼450 Ma) Oliverian Plutonic Suite rocks that intruded the Ammonoosuc Volcanics, forming domes along the core of the Bronson Hill anticlinorium, have Laurentian isotopic signatures. This suggests that the Ammonoosuc Volcanics were thrust westwardly over the Laurentian margin, and that Laurentian basement rocks are present under the Bronson Hill terrane. A plausible explanation for these relationships is that an easterly dipping subduction zone formed the Ammonoosuc Volcanics in the Tetagoughe–Exploits oceanic tract, just east of the coeval Popelogan arc. With the closure of the Iapetus Ocean, this terrane was thrust over the Laurentian margin. Subsequent to obduction of the Ammonoosuc Volcanics, subduction polarity flipped to the west, with the Oliverian arc resulting from a westerly dipping subduction zone that formed under the Taconic Orogeny-modified Laurentian margin.
Tectonic significance of Late Ordovician silicic magmatism, Avalon terrane, northern Antigonish Highlands, Nova Scotia 1 This article is one of a series of papers published in CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.2 Contribution to International Geological Correlation Programme (IGCP) Project 497.
Authors: Murphy J. Brendan , Hamilton Michael A. , LeBlanc Bryan
Published: March 2017

Avalonia was a microcontinent during most of the Ordovician, separating the Iapetus Ocean to the north from the Rheic Ocean to the south. In the northern Antigonish Highlands, Nova Scotia, volcanic rocks (Dunn Point and McGillivray Brook formations) underlie Early Silurian – Early Devonian strata (Arisaig Group) and were thought to represent extension that heralded the development of the basin into which Arisaig Group strata were deposited. However, recent U–Pb (zircon, thermal ionization mass spectrometry) data from rhyolite in the Dunn Point Formation (DPF) yielded an age of 460.0 ± 3.4 Ma, and, here, we report a concordant age of 454.5 ± 0.7 Ma for an ignimbrite in the overlying McGillivray Brook Formation (MBF). These data confirm a ca. 10 million year gap between volcanism and onset of Arisaig Group deposition, which occurred after accretion of Avalonia to Baltica. The DPF and MBF both resemble A-type SiO2-rich magmas. The MBF has very high concentrations of Zr (745–1965 ppm), Y (65–213 ppm), Nb (57 to 185 ppm), and high Ga/Al. Several MBF samples exhibit strong LREE depletion, consistent with fractionation of LREE-bearing accessory phases. εNdt values for MBF (t = 455 Ma) range from +1.5 to +3.9, and overlap with DPF rhyolites that range from +2.9 to +3.7. Depleted mantle model ages for MBF and DPF samples unaffected by accessory phase fractionation are between 0.9 and 1.2 Ga and are similar to TDM values in older (Neoproterozoic, Cambrian) crustally derived felsic rocks, suggesting derivation from the lower crustal basement beneath the Antigonish Highlands. DPF and MBF rocks were probably erupted in a local extensional environment within an ensialic arc, perhaps analogous to the modern Taupo Volcanic Zone in northern New Zealand.
Laurentia-derived detritus in the Badger Group of central Newfoundland: deposition during closing of the Iapetus Ocean1This article is one of a series of papers published in CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.2Geological Survey of Canada Contribution 20110273.
Authors: Waldron John W.F. , McNicoll Vicki J. , van Staal Cees R.
Published: March 2017

The Dunnage zone of central Newfoundland records the closing of an oceanic tract — the Iapetus Ocean. Within this tract, the Red Indian line separates arc terranes developed close to Laurentia (Notre Dame subzone) from those associated with the peri-Gondwanan terrane Ganderia (Exploits subzone). Sandstones and conglomerates of the Badger Group were deposited on the Exploits subzone, southeast of the Red Indian line, from Late Ordovician (Katian) to early Silurian (Llandovery) time. Two samples were collected from the base and top of the Badger Group for detrital zircon U/Pb dating. The lower sample yielded detrital zircon populations with a large statistical peak at ca. 1.0 Ga, and other features characteristic of derivation from Laurentian sources. Paleozoic zircons with ages from Late Cambrian to Late Ordovician were probably derived from the Notre Dame arc on the margin of Laurentia. The upper sample yielded a comparable age distribution, but with a much smaller proportion of Mesoproterozoic relative to Paleozoic detrital zircon. These results date the earliest arrival of Laurentia-derived detritus on the peri-Gondwanan Exploits subzone crust in the early Katian (ca. 455 Ma). However, the absence, in both samples, of Neoproterozoic grains suggests that there was still a seaway separating the Gander margin from arc terranes accreted to Laurentia until at least the middle Llandovery (ca. 436 Ma).
Preservation of terranes during the assembly of the Annieopsquotch Accretionary Tract: Inferences from the provenance of a Middle Ordovician ophiolite to arc transition, central Newfoundland Appalachians1Geological Survey of Canada Contribution 20100463.2This article is one of a series of papers published in this CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.
Authors: Coombs April M. , Zagorevski Alex , McNicoll Vicki , Hanchar John M.
Published: March 2017

The Newfoundland Appalachians are a classic area for studying the record of arc development and terrane accretion processes with excellent exposure to different crustal levels that are minimally deformed and metamorphosed. This area also provides a link between the once continuous Appalachian and Caledonian orogens. The Annieopsquotch Accretionary Tract lies along the Red Indian Line, within the peri-Laurentian realm of the central Newfoundland Appalachians. The Darriwilian (468–461 Ma) tectonostratigraphic units of the Annieopsquotch Accretionary Tract are commonly characterized by polymictic volcanogenic conglomerate horizons. A conglomerate horizon at the interface between a suprasubduction zone ophiolite and its calc-alkaline volcanic arc cover sequence is herein investigated for zircon and geochemical provenance. Geochronology revealed a maximum age of deposition of 467 ± 4 Ma with zircon inheritance ranging from ca. 500 to 2800 Ma, consistent with a peri-Laurentian continental basement source. Four types of volcanogenic conglomerate clasts are noted on the basis of lithogeochemistry: arc andesite; calc-alkaline basalt; tholeiitic basalt; and non-arc rhyodacite. Tholeiitic basalt clasts are likely locally derived, perhaps from the underlying Skidder Formation. Other volcanic clasts do not have any known geochemical equivalents in the Annieopsquotch Accretionary Tract and hence appear to be exotic. The dominant zircon population suggests that the exotic clasts were derived from a ca. 467 Ma peri-Laurentian andesitic volcanic arc that once formed part of the Annieopsquotch Accretionary Tract.
Paleomagnetic study of the late Neoproterozoic Bull Arm and Crown Hill formations (Musgravetown Group) of eastern Newfoundland: implications for Avalonia and West Gondwana paleogeography1This article is one of a series of papers published in CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.
Authors: Pisarevsky Sergei A. , McCausland Phil J.A. , Hodych Joseph P. , O’Brien Sean J. , Tait Jennifer A. , Murphy J. Brendan
Published: March 2017

A paleomagnetic study of subaerial volcanic rocks and associated siltstones of the Ediacaran Bull Arm Formation in the Avalon Zone of Newfoundland revealed a stable bipolar, hematite-borne primary remanence supported by positive conglomerate, contact, and fold tests. Mean remanence directions in two distal areas (Bonavista and Argentia) are similar, indicating a low paleolatitude position of Avalonia at ∼570 Ma. Redbeds of the overlying ∼550 Ma Crown Hill Formation also carry a primary bipolar hematite-borne remanence with moderate inclination, indicating that Avalonia remained at low to medium paleolatitudes through the end of the Ediacaran. Combining our results with previously published paleomagnetic data of Avalonia suggests moderate-scale drift of Avalonia through low southern paleolatitudes through the latter half of the Ediacaran, providing a paleogeographic context for the development of the first complex metazoan life.
A paleogeographical review of the peri-Gondwanan realm of the Appalachian orogen1This article is one of a series of papers published in this CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.
Authors: Pollock Jeffrey C. , Hibbard James P. , van Staal Cees R.
Published: March 2017

The eastern edge of the Appalachian orogen is composed of a collection of Neoproterozoic – early Paleozoic domains, Avalonia, Carolinia, Ganderia, Meguma, and Suwannee, which are exotic to North America. Differences in the geological histories of these peri-Gondwanan domains indicate that each separated independently from Gondwana, opening the Rheic Ocean in their wake. Cambrian departure of Ganderia and Carolina was followed by the Ordovician separation of Avalonia and Silurian separation of Meguma. After separation in the early Paleozoic, these domains constituted the borderline between the expanding Rheic Ocean and contracting Iapetus Ocean. They were transferred to Laurentia by early Silurian closure of Iapetus and Devonian–Carboniferous closure of the Rheic Ocean during the assembly of Gondwana and Laurentia into Pangaea. The first domain to arrive at Laurentia was Carolinia, which accreted in the Middle Ordovician during the Cherokee orogeny. Salinic accretion of Ganderia occurred shortly thereafter and was followed by the Acadian accretion of Avalonia. The Acadian orogeny was immediately followed by Middle Devonian – Early Carboniferous accretion of Meguma and possibly Suwannee which led to the Fammenian orogeny. The episodicity of orogeny suggests that the present location of these domains parallels their order of accretion. However, each of these crustal blocks was translated along strike by large-scale Late Devonian – Carboniferous dextral strike–slip motion. The breakup of Pangaea occurred outboard of the Paleozoic collision zones that accreted Carolinia, Ganderia, Avalonia, Meguma, and Suwannee to Laurentia, leaving these terranes appended to North America during the Mesozoic opening of the Atlantic.
Microplastic abundance and distribution in the open water and sediment of the Ottawa River, Canada, and its tributaries
Authors: Vermaire Jesse C. , Pomeroy Carrington , Herczegh Sofia M. , Haggart Owen , Murphy Meaghan
Published: March 2017

Microplastic pollution is prevalent in the Ottawa River, with all open water samples ( n = 62) and sediment samples ( n = 10) containing microplastics. The median microplastic concentration of nearshore 100 L water samples was 0.1 fragments per L (ranged between 0.05 and 0.24 fragments per L). The larger volume Manta trawls samples taken in the middle of the Ottawa River had an overall mean concentration of plastics of 1.35 fragments per m3. Plastic concentrations were significantly higher downstream of the wastewater treatment plant (1.99 fragments per m3) compared with upstream of the effluent output (0.71 fragments per m3), suggesting that the effluent plume is a pathway for plastic pollution to the Ottawa River. The mean concentration of microplastic fragments recovered in the sediment samples was 0.22 fragments per g dry weight. The abundance of microplastics in the sediment was not significantly related to the mean particle size or the organic content of the sediment. The most common form of plastic particles found was microfibers. These made up between 70% and 100% of all plastic particles observed, although plastic microbeads and secondary plastic fragments were also recovered.
Kähler submanifolds and the Umehara algebra
Authors: Cheng Xiaoliang , Di Scala Antonio J. , Yuan Yuan
Published: March 2017

We show that the indefinite complex space form [Formula: see text] is not a relative to the indefinite complex space form [Formula: see text] or [Formula: see text]. We further study whether two Fubini–Study spaces are relatives or not.
Dense holomorphic curves in spaces of holomorphic maps and applications to universal maps
Authors: Kusakabe Yuta
Published: March 2017

We study when there exists a dense holomorphic curve in a space of holomorphic maps from a Stein space. We first show that for any bounded convex domain [Formula: see text] and any connected complex manifold [Formula: see text], the space [Formula: see text] contains a dense holomorphic disc. Our second result states that [Formula: see text] is an Oka manifold if and only if for any Stein space [Formula: see text] there exists a dense entire curve in every path component of [Formula: see text].

In the second half of this paper, we apply the above results to the theory of universal functions. It is proved that for any bounded convex domain [Formula: see text], any fixed-point-free automorphism of [Formula: see text] and any connected complex manifold [Formula: see text], there exists a universal map [Formula: see text]. We also characterize Oka manifolds by the existence of universal maps.
Effect of connection on transport between scale free networks
Authors: Baba A. Ould , Bamaarouf O. , Rachadi A. , Ez-Zahraouy H.
Published: March 2017

Using numerical simulations, we investigate the effects of the connectivity and topologies of network on the quality of transport between connected scale free networks. Hence, the flow as the electrical conductance between connected networks is calculated. It is found that the conductance distribution between networks follow a power law [Formula: see text] where [Formula: see text] is the exponent of the global Network of network, we show that the transport in the symmetric growing preferential attachment connection is more efficient than the symmetric static preferential attachment connection. Furthermore, the differences of transport and networks communications properties in the different cases are discussed.
Multiscale volatility duration characteristics on financial multi-continuum percolation dynamics
Authors: Wang Min , Wang Jun
Published: March 2017

A random stock price model based on the multi-continuum percolation system is developed to investigate the nonlinear dynamics of stock price volatility duration, in an attempt to explain various statistical facts found in financial data, and have a deeper understanding of mechanisms in the financial market. The continuum percolation system is usually referred to be a random coverage process or a Boolean model, it is a member of a class of statistical physics systems. In this paper, the multi-continuum percolation (with different values of radius) is employed to model and reproduce the dispersal of information among the investors. To testify the rationality of the proposed model, the nonlinear analyses of return volatility duration series are preformed by multifractal detrending moving average analysis and Zipf analysis. The comparison empirical results indicate the similar nonlinear behaviors for the proposed model and the actual Chinese stock market.
Synchronization Dynamics of Two Heterogeneous Chaotic Rulkov Neurons with Electrical Synapses
Authors: Cheng Lifang , Cao Hongjun
Published: March 2017

Two heterogeneous chaotic Rulkov neurons with electrical synapses are investigated in this paper. First, we study the ability of the second neuron to modify the dynamics of the first neuron. It is shown that when the parameters of the first neuron are located at the vicinity of the Neimark–Sacker bifurcation curves the first firing neuron can be controlled into the quiescent state when coupled with the second neuron. While the parameters of the first neuron are near the flip bifurcation curves the first firing neuron cannot be suppressed. Second, we discuss burst synchronization for two bursting neurons and two tonic spiking neurons. It is shown that two heterogeneous chaotic Rulkov neurons with tonic spiking firing cannot reach anti-phase synchronization under the inhibitory coupling, which is different from the property of nonchaotic Rulkov neurons. Finally, we show that for two bursting neurons if the coupling is strong enough then burst synchronization can be converted into spike synchronization. However, complete synchronization cannot be achieved for any strong coupling.