bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determinants of litter decomposition rates in a tropical forest: functional traits, phylogeny and ecological succession
Authors: Szefer Piotr , Carmona Carlos P. , Chmel Kryštof , Konečná Marie , Libra Martin , Molem Kenneth , Novotný Vojtěch , Segar Simon T. , Švamberková Eva , Topliceanu Theodor‐Sebastian , Lepš Jan 
Published: December 2016

Plant litter decomposition is one of the most important processes in terrestrial ecosystems, as it is a key factor in nutrient cycling. Decomposition rates depend on environmental factors, but also plant traits, as these determine the character of detritus. We measured litter decomposition rate for 57 common tree species displaying a variety of functional traits within four sites in primary and four sites in secondary tropical forest in Madang Province, Papua New Guinea. The phylogenetic relationships between these trees were also estimated using molecular data. The leaves collected from different tree species were dried for two days, placed into detritus bags and exposed to ambient conditions for two months. Nitrogen, carbon and ash content were assessed as quantitative traits and used together with a phylogenetic variance– covariance matrix as predictors of decomposition rate. The analysis of the tree species composition from 96 quadrats located along a successional gradient of swidden agriculture enabled us to determine successional preferences for individual species.Nitrogen content was the only functional trait measured to be significantly positively correlated with decomposition rate. Controlling for plant phylogeny did not influence our conclusions, but including phylogeny demonstrated that the mainly early successional family Euphorbiaceae is characterized by a particularly high decomposition rate. The acquisitive traits (high nitrogen content and low wood density) correlated with rapid decomposition were characteristic for early successional species. Decomposition rate thus decreased from early successional to primary forest species. However, the decomposition of leaves from the same species was significantly faster in primary than in secondary forest stands, very probably because the high humidity of primary forest environments keeps the decomposing material wetter.
Ten‐Year Clinical Experience with the Lumenless, Catheter‐Delivered, 4.1‐Fr Diameter Pacing Lead in Patients with and without Congenital Heart
Authors: BANSAL NEHA , SAMUEL SHARMEEN , ZELIN KATHLEEN , KARPAWICH PETER P. 
Published: December 2016

BackgroundPatients with congenital heart defects (CHD) often present more challenges to pacing therapy due to anatomy than those without CHD. The lumenless, 4.1Fr diameter M3830 pacing lead (Medtronic, Inc., Minneapolis, MN, USA), approved for use in 2005, has, to date, reported to have excellent short‐term (<6 years) lead performance. Unfortunately, very long‐term performance is unknown, especially among CHD patients and with implants at alternate pacing (AP) sites. This study reports a 10‐year clinical experience with the M3830 lead.MethodsRecords of patients who received the M3830 lead were reviewed: patient demographics, implant techniques and locations, sensing and pacing characteristics, impedances (Imp), and any complications at implant and follow‐up.ResultsFrom 2005 to 2015, 141 patients (ages 2–50, mean 20.1 years, 57% males) received 212 leads: atrial 115; ventricle 97. CHD was present in 62% of patients. Leads were inserted at AP sites in 96% of patients. Postimplant follow‐up was from 3 months to 10 years (mean 56.3 months). Comparative implant versus follow‐up values (mean ± standard deviation) were available on 196 leads (92.5%), showing persistently low (<1 v @ 0.4–0.5 ms) pacing thresholds (P = 0.57). Sensing was also comparable (atrial leads, P = 0.41; ventricular leads, P = 0.9). Impedances differed (P < 0.05) but remained within the normal range. Two A leads became dislodged and one was repositioned while two other leads (1 A, 1 V) were extracted. There are no differences observed in the pacing characteristics between the CHD and non‐CHD groups on follow‐up.ConclusionsThe 4.1Fr lumenless pacing lead shows ease of implant regardless of CHD or AP site, excellent very long‐term (10 years) stability, and performance indices with a very low rate of complications.
Nationalism and Construction of Regional Security Order in Northeast Asia
Authors: Qiu Fahua 
Published: December 2016

AbstractBased on the perspectives of popular nationalism and state nationalism, this article investigates the current status of nationalism as well as its effects on the regional security order in Northeast Asia. The rise of nationalism in Northeast Asia is multifaceted and presents a dynamic development trend, which has a profound impact on the regional security order in Northeast Asia. Although the popular nationalism of Northeast Asian nations has various effects on the diplomatic decision‐making of the respective governments, all of these versions of nationalism affect normal communications among nations in the region. Thus, each government should be careful when utilizing nationalism to realize its political purposes. Indeed, Japan and China should learn from the lessons of history in World War II and avoid falling into the abyss of state nationalism. Each nation in Northeast Asia should pay more attention to the rise of nationalism in the region, constrain its narrow‐mindedness and exclusiveness, and aspire to rational patriotism. By doing so, a peaceful, secure, and prosperous regional security order in Northeast Asia could be constructed.
The Tourism of North Korea in the Kim Jong‐un Era: Propaganda, Profitmaking, and Possibilities for Engagement
Authors: Ouellette Dean J. 
Published: December 2016

AbstractIn this article, I explore changes in North Korean tourism, with a focus on the industry since Kim Jong‐un came to power. The study: highlights North Korea's concept of “socialist tourism” and recent developments; investigates Western social media to uncover how non‐mainstream digital media characterizes the country as a unique travel destination; discusses investment and profitmaking with respect to Chinese investors and tourists; and suggests tourism as a possible path to consider for future peaceful engagement approaches.
The Lr34 adult plant rust resistance gene provides seedling resistance in durum wheat without senescence
Authors: Rinaldo Amy , Gilbert Brian , Boni Rainer , Krattinger Simon G. , Singh Davinder , Park Robert F. , Lagudah Evans , Ayliffe Michael 
Published: December 2016

SummaryThe hexaploid wheat (Triticum aestivum) adult plant resistance gene, Lr34/Yr18/Sr57/Pm38/Ltn1, provides broad‐spectrum resistance to wheat leaf rust (Lr34), stripe rust (Yr18), stem rust (Sr57) and powdery mildew (Pm38) pathogens, and has remained effective in wheat crops for many decades. The partial resistance provided by this gene is only apparent in adult plants and not effective in field‐grown seedlings. Lr34 also causes leaf tip necrosis (Ltn1) in mature adult plant leaves when grown under field conditions. This D genome‐encoded bread wheat gene was transferred to tetraploid durum wheat (T. turgidum) cultivar Stewart by transformation. Transgenic durum lines were produced with elevated gene expression levels when compared with the endogenous hexaploid gene. Unlike nontransgenic hexaploid and durum control lines, these transgenic plants showed robust seedling resistance to pathogens causing wheat leaf rust, stripe rust and powdery mildew disease. The effectiveness of seedling resistance against each pathogen correlated with the level of transgene expression. No evidence of accelerated leaf necrosis or up‐regulation of senescence gene markers was apparent in these seedlings, suggesting senescence is not required for Lr34 resistance, although leaf tip necrosis occurred in mature plant flag leaves. Several abiotic stress‐response genes were up‐regulated in these seedlings in the absence of rust infection as previously observed in adult plant flag leaves of hexaploid wheat. Increasing day length significantly increased Lr34 seedling resistance. These data demonstrate that expression of a highly durable, broad‐spectrum adult plant resistance gene can be modified to provide seedling resistance in durum wheat.
Improved Detection of Changes in Species Richness in High Diversity Microbial Communities
Authors: Willis Amy , Bunge John , Whitman Thea 
Published: December 2016

SummaryBiodiversity is important for balance and function of a broad variety of ecosystems, and identifying factors that influence biodiversity can assist environmental management and maintenance. However, low abundance taxa are often missing from ecosystem surveys. These rare taxa, which may be critical to the ecosystem function, are not accounted for in existing methods for detecting changes in species richness. We introduce a model for total (observed and unobserved) biodiversity that explicitly accounts for these rare taxa. Our method permits rigorous testing for both heterogeneity and biodiversity changes, and simultaneously improves type I and II error rates compared with existing methods. To estimate model parameters we utilize the well-developed literature of meta-analysis. The problem of substantial low abundance taxa missing from samples is especially pronounced in microbiomes, which are the focus of our case-studies.
Perception and signalling of light and temperature cues in plants
Authors: Legris Martina , Nieto Cristina , Sellaro Romina , Prat Salomé , Casal Jorge J. 
Published: December 2016

SummaryLight and temperature patterns are often correlated under natural plant growth conditions. In this review, we analyse the perception and signalling mechanisms shared by both these environmental cues and discuss the functional implications of their convergence to control plant growth. The first point of integration is the phytochrome B (phyB) receptor, which senses light and temperature. Downstream of phyB, the signalling core comprises two branches, one involving PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and the other CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) and ELONGATED HYPOCOTYL 5 (HY5). The dynamics of accumulation and/or localization of each of these core signalling components depend on light and temperature conditions. These pathways are connected through COP1, which enhances the activity of PIF4. The circadian clock modulates this circuit, since EARLY FLOWERING 3 (ELF3), an essential component of the evening complex (EC), represses expression of the PIF4 gene and PIF4 transcriptional activity. Phytochromes are probably not the only entry point of temperature into this network, but other sensors remain to be established. The sharing of mechanisms of action for two distinct environmental cues is to some extent unexpected, as it renders these responses mutually dependent. There are nonetheless many ecological contexts in which such a mutual influence could be beneficial.
Physiological redox signalling and regulation of ion channels: implications for pulmonary hypertension
Authors: Ward Jeremy P. T. 
Published: December 2016

New Findings
What is the topic of this review?
The review concerns the role of reactive oxygen species as physiological second messengers in potentiating G‐protein‐coupled receptor‐mediated vasoconstriction and its potential dysregulation by oxidant stress in pulmonary hypertension.

What advances does it highlight?
The review highlights the concept that physiological signalling by reactive oxygen species must normally be highly compartmentalized to prevent self‐regenerating oxidant stress and promiscuous and uncontrolled signalling, which contribute to the aetiology.

Pulmonary hypertension is associated with oxidant stress and increased generation of reactive oxygen species (ROS) by NADPH oxidases (NOX), mitochondria and other sources. There is considerable evidence that these contribute to the aetiology via promotion of pulmonary vascular remodelling, endothelial dysfunction and enhanced vasoreactivity. However, it is now recognized that ROS act as important signalling mediators and second messengers in normal physiological conditions. Many ion channels and protein kinases crucial to pulmonary vascular function are directly or indirectly affected by redox/ROS, including K+, Ca2+ and non‐selective cation channels and Rho kinase. However, the inherent difficulties in quantifying ROS, particularly in subcellular compartments, make it uncertain whether these reported effects are of relevance in physiological rather than pathological conditions. In an attempt to address such issues, we have focused on the role of physiologically generated ROS in the regulation of G‐protein‐coupled receptor (GPCR)‐activated vasoconstrictor pathways. We have recently reported a novel mechanism whereby low concentrations of GPCR‐linked vasoconstrictors greatly potentiate Ca2+ entry via a NOX1‐ and ROS‐mediated pathway parallel to the classical vasoconstrictor pathways of Ca2+ mobilization and activation of Rho kinase. Our findings imply that ROS signalling is highly compartmentalized in physiological conditions, but that this may be compromised by pathological increases in oxidant production, for example in pulmonary hypertension, leading to promiscuous actions that contribute to the aetiology. This model is consistent with the proposal that targeted antioxidants could prove to be an effective therapy for pulmonary hypertension.
A critical period of corticomuscular and EMG–EMG coherence detection in healthy infants aged 9–25 weeks
Authors: Ritterband‐Rosenbaum Anina , Herskind Anna , Li Xi , Willerslev‐Olsen Maria , Olsen Mikkel Damgaard , Farmer Simon Francis , Nielsen Jens Bo 
Published: December 2016

Key points
The early postnatal development of functional corticospinal connections in human infants is not fully clarified.
Corticospinal drive to upper and lower limb muscle shows developmental changes with an increased functional coupling in infants between 9 and 25 weeks in the beta frequency band.
The changes in functional coupling coincide with the developmental period where fidgety movements are present in healthy infants.
Data support a possible sensitive period where functional connections between corticospinal tract fibres and spinal motoneurones undergo activity‐dependent reorganization.
AbstractThe early postnatal development of functional corticospinal connections in human infants is not fully clarified. We used EEG and EMG to investigate the development of corticomuscular and intramuscular coherence as indicators of functional corticospinal connectivity in healthy infants aged 1–66 weeks. EEG was recorded over leg and hand area of motor cortex. EMG recordings were made from right ankle dorsiflexor and right wrist extensor muscles. Quantification of the amount of corticomuscular coherence in the 20–40 Hz frequency band showed a significantly larger coherence for infants aged 9–25 weeks compared to younger and older infants. Coherence between paired EMG recordings from tibialis anterior muscle in the 20–40 Hz frequency band was also significantly larger for the 9–25 week age group. A low‐amplitude, broad‐duration (40–50 ms) central peak of EMG–EMG synchronization was observed for infants younger than 9 weeks, whereas a short‐lasting (10–20 ms) central peak was observed for EMG–EMG synchronization in older infants. This peak was largest for infants aged 9–25 weeks. These data suggest that the corticospinal drive to lower and upper limb muscles shows significant developmental changes with an increase in functional coupling in infants aged 9–25 weeks, a period which coincides partly with the developmental period of normal fidgety movements. We propose that these neurophysiological findings may reflect the existence of a sensitive period where the functional connections between corticospinal tract fibres and spinal motoneurones undergo activity‐dependent reorganization. This may be relevant for the timing of early therapy interventions in infants with pre‐ and perinatal brain injury.
Non‐chemosensitive parafacial neurons simultaneously regulate active expiration and airway patency under hypercapnia in rats
Authors: de Britto Alan A. , Moraes Davi J. A. 
Published: December 2016

Key points
Hypercapnia or parafacial respiratory group (pFRG) disinhibition at normocapnia evokes active expiration in rats by recruitment of pFRG late‐expiratory (late‐E) neurons.
We show that hypercapnia simultaneously evoked active expiration and exaggerated glottal dilatation by late‐E synaptic excitation of abdominal, hypoglossal and laryngeal motoneurons. Simultaneous rhythmic expiratory activity in previously silent pFRG late‐E neurons, which did not express the marker of ventral medullary CO2‐sensitive neurons (transcription factor Phox2b), was also evoked by hypercapnia.
Hypercapnia‐evoked active expiration, neural and neuronal late‐E activities were eliminated by pFRG inhibition, but not after blockade of synaptic excitation.
Hypercapnia produces disinhibition of non‐chemosensitive pFRG late‐E neurons to evoke active expiration and concomitant cranial motor respiratory responses controlling the oropharyngeal and upper airway patency.
AbstractHypercapnia produces active expiration in rats and the recruitment of late‐expiratory (late‐E) neurons located in the parafacial respiratory group (pFRG) of the ventral medullary brainstem. We tested the hypothesis that hypercapnia produces active expiration and concomitant cranial respiratory motor responses controlling the oropharyngeal and upper airway patency by disinhibition of pFRG late‐E neurons, but not via synaptic excitation. Phrenic nerve, abdominal nerve (AbN), cranial respiratory motor nerves, subglottal pressure, and medullary and spinal neurons/motoneurons were recorded in in situ preparations of juvenile rats. Hypercapnia evoked AbN active expiration, exaggerated late‐E discharges in cranial respiratory motor outflows, and glottal dilatation via late‐E synaptic excitation of abdominal, hypoglossal and laryngeal motoneurons. Simultaneous rhythmic late‐E activity in previously silent pFRG neurons, which did not express the marker of ventral medullary CO2‐sensitive neurons (transcription factor Phox2b), was also evoked by hypercapnia. In addition, hypercapnia‐evoked AbN active expiration, neural and neuronal late‐E activities were eliminated by pFRG inhibition, but not after blockade of synaptic excitation. On the other hand, pFRG inhibition did not affect either hypercapnia‐induced inspiratory increases in respiratory motor outflows or CO2 sensitivity of the more medial Phox2b‐positive neurons in the retrotrapezoid nucleus (RTN). Our data suggest that neither RTN Phox2b‐positive nor other CO2‐sensitive brainstem neurons activate Phox2b‐negative pFRG late‐E neurons under hypercapnia to produce AbN active expiration and concomitant cranial motor respiratory responses controlling the oropharyngeal and upper airway patency. Hypercapnia produces disinhibition of non‐chemosensitive pFRG late‐E neurons in in situ preparations of juvenile rats to activate abdominal, hypoglossal and laryngeal motoneurons.
LacI Transcriptional Regulatory Networks in Clostridium thermocellum DSM1313
Authors: Wilson Charlotte M. , Klingeman Dawn M. , Schlachter Caleb , Syed Mustafa H. , Wu Chia-wei , Guss Adam M. , Brown Steven D. 
Published: December 2016

ABSTRACT

Organisms regulate gene expression in response to the environment to coordinate metabolic reactions.
Clostridium thermocellum
expresses enzymes for both lignocellulose solubilization and its fermentation to produce ethanol. One LacI regulator termed GlyR3 in
C. thermocellum
ATCC 27405 was previously identified as a repressor of neighboring genes with repression relieved by laminaribiose (a β-1,3 disaccharide). To better understand the three
C. thermocellum
LacI regulons, deletion mutants were constructed using the genetically tractable DSM1313 strain. DSM1313
lacI
genes Clo1313_2023, Clo1313_0089, and Clo1313_0396 encode homologs of GlyR1, GlyR2, and GlyR3 from strain ATCC 27405, respectively. Growth on cellobiose or pretreated switchgrass was unaffected by any of the gene deletions under controlled-pH fermentations. Global gene expression patterns from time course analyses identified glycoside hydrolase genes encoding hemicellulases, including cellulosomal enzymes, that were highly upregulated (5- to 100-fold) in the absence of each LacI regulator, suggesting that these were repressed under wild-type conditions and that relatively few genes were controlled by each regulator under the conditions tested. Clo1313_2022, encoding lichenase enzyme LicB, was derepressed in a Δ
glyR1
strain. Higher expression of Clo1313_1398, which encodes the Man5A mannanase, was observed in a Δ
glyR2
strain, and α-mannobiose was identified as a probable inducer for GlyR2-regulated genes. For the Δ
glyR3
strain, upregulation of the two genes adjacent to
glyR3
in the
celC-glyR3-licA
operon was consistent with earlier studies. Electrophoretic mobility shift assays have confirmed LacI transcription factor binding to specific regions of gene promoters.

IMPORTANCE
Understanding
C. thermocellum
gene regulation is of importance for improved fundamental knowledge of this industrially relevant bacterium. Most LacI transcription factors regulate local genomic regions; however, a small number of those genes encode global regulatory proteins with extensive regulons. This study indicates that there are small specific
C. thermocellum
LacI regulons. The identification of LacI repressor activity for hemicellulase gene expression is a key result of this work and will add to the small body of existing literature on the area of gene regulation in
C. thermocellum
.
Genome Integration and Excision by a New Streptomyces Bacteriophage, ϕJoe
Authors: Fogg Paul C. M. , Haley Joshua A. , Stark W. Marshall , Smith Margaret C. M. 
Published: December 2016

ABSTRACT

Bacteriophages are the source of many valuable tools for molecular biology and genetic manipulation. In
Streptomyces
, most DNA cloning vectors are based on serine integrase site-specific DNA recombination systems derived from phage. Because of their efficiency and simplicity, serine integrases are also used for diverse synthetic biology applications. Here, we present the genome of a new
Streptomyces
phage, ϕJoe, and investigate the conditions for integration and excision of the ϕJoe genome. ϕJoe belongs to the largest
Streptomyces
phage cluster (R4-like) and encodes a serine integrase. The
attB
site from
Streptomyces venezuelae
was used efficiently by an integrating plasmid, pCMF92, constructed using the ϕJoe
int-attP
locus. The
attB
site for ϕJoe integrase was occupied in several
Streptomyces
genomes, including that of
S. coelicolor
, by a mobile element that varies in gene content and size between host species. Serine integrases require a phage-encoded recombination directionality factor (RDF) to activate the excision reaction. The ϕJoe RDF was identified, and its function was confirmed
in vivo
. Both the integrase and RDF were active in
in vitro
recombination assays. The ϕJoe site-specific recombination system is likely to be an important addition to the synthetic biology and genome engineering toolbox.

IMPORTANCE
Streptomyces
spp. are prolific producers of secondary metabolites, including many clinically useful antibiotics. Bacteriophage-derived integrases are important tools for genetic engineering, as they enable integration of heterologous DNA into the
Streptomyces
chromosome with ease and high efficiency. Recently, researchers have been applying phage integrases for a variety of applications in synthetic biology, including rapid assembly of novel combinations of genes, biosensors, and biocomputing. An important requirement for optimal experimental design and predictability when using integrases, however, is the need for multiple enzymes with different specificities for their integration sites. In order to provide a broad platform of integrases, we identified and validated the integrase from a newly isolated
Streptomyces
phage, ϕJoe. ϕJoe integrase is active
in vitro
and
in vivo
. The specific recognition site for integration is present in a wide range of different actinobacteria, including
Streptomyces venezuelae
, an emerging model bacterium in
Streptomyces
research.