bluuebunny/crossref_metadata_2025 huggingface dataset:
A Case Study of Evolvability and Excess on the B-52 Stratofortress and F/A-18 Hornet
Authors: Long Daniel , Ferguson Scott
Published: November 2017

The moment a system is put into service it begins to lose value as technological and societal changes accrue while the system is frozen in the state it was constructed. System decision makers are faced with the choice of accepting a decline in performance, updating the design, or retiring the system. Each time a decision maker faces these alternatives, the value of the available options must be evaluated to determine the preferred course of action. A design that can adapt to changes with minimal cost should provide more value over a longer period than a system that is initially less costly, but less adaptable. This is especially desirable for systems that have large initial costs and/or a lengthy development cycle. The purpose of this paper is to evaluate the United States Air Force (USAF) B-52 Stratofortress and the United States Navy (USN) F/A-18 Hornet to characterize the changes in desired capabilities and what system attributes allowed them to either successfully adapt or prevented them from adapting. These observations allow the development of heuristics that designers can use during system design to enhance system lifetime value.
A Smart Device to Substitute the Neurothesiometer
Authors: Vaughan Neil , Dubey Venketesh N. , Hickish Tamas , Cole Jonathan
Published: November 2017

This paper presents a patented smart point-of-care testing (POCT) system for the diagnosis and grading of peripheral neuropathy at the patient’s home or care center. The device aims to detect changes or worsening of a patient’s neuropathy.

Our system utilizes the vibration motor within a smartphone, applied through a 3D printed probe attachment to detect sensation loss in vibration sensitivity threshold (VST). A smartphone app displays several neuropathy questionnaires to the user to identify and monitor changes in their condition.

This paper presents results from comparison between the new smart device and the gold standard Neurothesiometer. Results suggest that the new device performs closely to the gold standard in terms of the frequency and amplitude of vibration.
Integrating Design and Optimization Tools: A Designer Centered Study
Authors: Burnell Edward , Stern Michael , Flooks Ana , Yang Maria C.
Published: November 2017

Exploring design options for additively manufactured parts generally requires separate, sequentially applied software for design, analysis, and optimization. To evaluate the effect of integrating these capabilities within a single tool we conducted a controlled human subjects study. Three tools with different degrees of integration were created for two test cases of structural trusses, and it was found that increased integration improved quality, speed, and efficiency of the design process. After a quarter of their total time with the problems, 50% of designers with a fully integrated tool had a better design than 75% of other designers ever would. After that point, the top 50% of designers went on to explore a design space unreached with other tools. It appears that integration, and in particular the integration of optimization, leads to better performance by making it possible to explore complex designs and achieve outcomes which would be inaccessible to conventional tools.
Design of Optimal Fractional Luenberger Observers for Linear Fractional-Order Systems
Authors: Dabiri Arman , Butcher Eric A.
Published: November 2017

Optimal fractional Luenberger observers for linear fractional-order systems are developed using the fractional Chebyshev collocation (FCC) method. It is shown that the design method has advantages over existing Luenberger design methods for fractional order systems. To accomplish this, the state transition operator for the solution of linear fractional-order systems is defined in a Banach space and discretized using the FCC method. In addition, the discretized state transition operator is obtained by using the FCC method. Next, the optimal observer gains are obtained by minimizing the spectral radius of the state transition operator for the observer,while ensuring that the observer responds faster than the controller. Finally, a numerical example is provided to demonstrate the validity and the efficiency of the proposed method.
Function Modeling: Comparison of Chaining Methods Using Protocol Study and Designer Study
Authors: Patel Apurva , Kramer William S. , Flynn Michelle , Summers Joshua D. , Shuffler Porter Marissa L.
Published: November 2017

Data was collected from a designer study and a protocol study where participants were asked to create function structure models using a seed model provided to them. This seed model was generated using three chaining methods: forward chaining, backward chaining, or nucleation; and the models were also created to a certain level of completion (10%, 40% or 80%). The resulting models will be analyzed using a count of functions and flows in the model as well as a previously developed scoring method. The aim of this comparison is to investigate whether the different chaining methods yield different results, as well as identify if the participants are more inclined to use a specific chaining method.
Challenges in Using a Delphi Method to Formalize Conceptual Understanding in Functional Reasoning
Authors: Scott Michael J. , Allen Margaret G. , Gaur Diksha
Published: November 2017

A project to develop a concept inventory for functional reasoning in engineering design using a Delphi method encountered some unanticipated difficulties at the outset. The anonymous elicitation of a list of candidate concepts from an expert panel was expected to be a straightforward first step in a process in which the main work would be the creation and validation of multiple choice questions to probe understanding of these concepts. Low response rates and inconsistent concept descriptions led to a reconsideration of the nature of the concept inventory project. The early results from the project are discussed and compared with a similar stage of a different concept inventory project in thermodynamics. Implications of this comparison for the field of functional reasoning and the development of concept inventories for relatively immature fields are discussed.
Is there a correlation between kidney shear wave velocity measured with VTQ and histological parameters in patients with chronic glomerulonephritis? A pilot study
Authors: Bob Flaviu , Grosu Iulia , Sporea Ioan , Bota Simona , Popescu Alina , Sirli Roxana , Petrica Ligia , Schiller Adalbert
Published: November 2017

Aim: To analyze the relationship between shear wave velocity in the kidney measured by point shear wave elastography using Virtual Touch Quantification (VTQ) (Siemens Acuson S2000) and histological parameters obtained from renal biopsies, in patients with chronic glomerulonephritis (CGN).Material and methods: The study group included 20 patients (mean age 47.95±13.59 years) with different types of CGN, that had underwent renal biopsy and 57 normal controls (mean age 38.07±17.32 years). In all patients, five valid stiffness measurements were obtained in each kidney, with the patient in lateral decubitus. Regarding the histological results, we assessed the presence or absence of glomerulosclerosis, interstitial fibrosis, and arteriolo-hyalinosis.Results: In patients with CGN we obtained the following mean values of VTQ values: right kidney: 2.12±0.81 m/s, left kidney 1.65±0.54 m/s, while in the normal controls significantly higher VTQ values were obtained: right kidney 2.69±0.72 m/s (p=0.004), left kidney 2.48±0.73 m/s (p<0.0001). In patients with CGN no statistically significant correlations between VTQ values and eGFR (r=0.37, p=0.12) or proteinuria (r=0.2, p=0.37) were found. We found significantly lower VTQ values in patients with interstitial fibrosis (1.46 vs. 1.99 m/s, p<0.05) and also in patients with arteriolo-hyalinosis (1.55 vs. 2.47 m/s, p<0.05).Conclusion: Our pilot study shows that shear wave velocity values in patients with CGN are significantly lower compared to normal controls, and there is a tendency to decrease with the decrease of eGFR, with the presence of interstitial fibrosis and of arteriolo-hyalinosis.
Prostate ultrasound: back in business!
Authors: Crisan Nicolae , Andras Iulia , Radu Corina , Andras David , Coman Radu-Tudor , Tucan Paul , Pisla Doina , Crisan Dana , Coman Ioan
Published: November 2017

The use of grey scale prostate ultrasound decreased after the implementation of magnetic resonance imaging (MRI) for the diagnosis and evaluation of prostate cancer. The new developments, such as multiparametric ultrasound and MRI-ultrasound fusion technology, renewed the interest for this imaging method in the assessment of prostate cancer. The purpose of this paper was to review the current role of prostate ultrasound in the setting of these new applications. A thorough reevaluation of the selection criteria of the patients is required to assess which patients would benefit from multiparametric ultrasound, who wouldbenefit from multiparametric MRI or the combination of both to assist prostate biopsy in order to ensure the balance between overdiagnosis and underdiagnosis of prostate cancer.
Review Article: Active scanning probes: A versatile toolkit for fast imaging and emerging nanofabrication
Authors: Rangelow Ivo W. , Ivanov Tzvetan , Ahmad Ahmad , Kaestner Marcus , Lenk Claudia , Bozchalooi Iman S. , Xia Fangzhou , Youcef-Toumi Kamal , Holz Mathias , Reum Alexander
Published: November 2017

With the recent advances in the field of nanotechnology, measurement and manipulation requirements at the nanoscale have become more stringent than ever before. In atomic force microscopy, high-speed performance alone is not sufficient without considerations of other aspects of the measurement task, such as the feature aspect ratio, required range, or acceptable probe-sample interaction forces. In this paper, the authors discuss these requirements and the research directions that provide the highest potential in meeting them. The authors elaborate on the efforts toward the downsizing of self-sensed and self-actuated probes as well as on upscaling by active cantilever arrays. The authors present the fabrication process of active probes along with the tip customizations carried out targeting specific application fields. As promising application in scope of nanofabrication, field emission scanning probe lithography is introduced. The authors further discuss their control and design approach. Here, microactuators, e.g., multilayer microcantilevers, and macroactuators, e.g., flexure scanners, are combined in order to simultaneously meet both the range and speed requirements of a new generation of scanning probe microscopes.
Interdependence of Primary Metabolism and Xenobiotic Mitigation Characterizes the Proteome of Bjerkandera adusta during Wood Decomposition
Authors: Moody S. C. , Dudley E. , Hiscox J. , Boddy L. , Eastwood D. C.
Published: November 2017

The aim of the current work was to identify key features of the fungal proteome involved in the active decay of beechwood blocks by the white rot fungusBjerkandera adustaat 20°C and 24°C. A combination of protein and domain analyses ensured a high level of annotation, which revealed that while the variation in the proteins identified was high between replicates, there was a considerable degree of functional conservation between the two temperatures. Further analysis revealed differences in the pathways and processes employed by the fungus at the different temperatures, particularly in relation to nutrient acquisition and xenobiotic mitigation. Key features showing temperature-dependent variation in mechanisms for both lignocellulose decomposition and sugar utilization were found, alongside differences in the enzymes involved in mitigation against damage caused by toxic phenolic compounds and oxidative stress.

IMPORTANCEThis work was conducted using the wood decay fungusB. adusta, grown on solid wood blocks to closely mimic the natural environment, and gives greater insight into the proteome of an important environmental fungus during active decay. We show that a change in incubation temperature from 20°C to 24°C altered the protein profile. Proteomic studies in the field of white-rotting basidiomycetes have thus far been hampered by poor annotation of protein databases, with a large proportion of proteins simply with unknown function. This study was enhanced by extensive protein domain analysis, enabling a higher level of functional assignment and greater understanding of the proteome composition. This work revealed a strong interdependence of the primary process of nutrient acquisition and specialized metabolic processes for the detoxification of plant extractives and the phenolic breakdown products of lignocellulose.
Distribution and Phylogeny of Microsymbionts Associated with Cowpea (Vigna unguiculata) Nodulation in Three Agroecological Regions of Mozambique
Authors: Chidebe Ifeoma N. , Jaiswal Sanjay K. , Dakora Felix D.
Published: November 2017

Cowpea derives most of its N nutrition from biological nitrogen fixation (BNF) via symbiotic bacteroids in root nodules. In Sub-Saharan Africa, the diversity and biogeographic distribution of bacterial microsymbionts nodulating cowpea and other indigenous legumes are not well understood, though needed for increased legume production. The aim of this study was to describe the distribution and phylogenies of rhizobia at different agroecological regions of Mozambique using PCR of the BOX element (BOX-PCR), restriction fragment length polymorphism of the internal transcribed spacer (ITS-RFLP), and sequence analysis of ribosomal, symbiotic, and housekeeping genes. A total of 122 microsymbionts isolated from two cowpea varieties (IT-1263 and IT-18) grouped into 17 clades within the BOX-PCR dendrogram. The PCR-ITS analysis yielded 17 ITS types for the bacterial isolates, while ITS-RFLP analysis placed all test isolates in six distinct clusters (I to VI). BLAST
n
sequence analysis of 16S rRNA and four housekeeping genes (
glnII
,
gyrB
,
recA
, and
rpoB
) showed their alignment with
Rhizobium
and
Bradyrhizobium
species. The results revealed a group of highly diverse and adapted cowpea-nodulating microsymbionts which included
Bradyrhizobium pachyrhizi
,
Bradyrhizobium arachidis
,
Bradyrhizobium yuanmingense
, and a novel
Bradyrhizobium
sp., as well as
Rhizobium tropici
,
Rhizobium pusense
, and
Neorhizobium galegae
in Mozambican soils. Discordances observed in single-gene phylogenies could be attributed to horizontal gene transfer and/or subsequent recombinations of the genes. Natural deletion of 60 bp of the
gyrB
region was observed in isolate TUTVU7; however, this deletion effect on DNA gyrase function still needs to be confirmed. The inconsistency of
nifH
with core gene phylogenies suggested differences in the evolutionary history of both chromosomal and symbiotic genes.

IMPORTANCE
A diverse group of both
Bradyrhizobium
and
Rhizobium
species responsible for cowpea nodulation in Mozambique was found in this study. Future studies could prove useful in evaluating these bacterial isolates for symbiotic efficiency and strain competitiveness in Mozambican soils.
Effects of Reduced and Enhanced Glycogen Pools on Salt-Induced Sucrose Production in a Sucrose-Secreting Strain of Synechococcus elongatus PCC 7942
Authors: Qiao Cuncun , Duan Yangkai , Zhang Mingyi , Hagemann Martin , Luo Quan , Lu Xuefeng
Published: November 2017

Sucrose and glycogen syntheses in cyanobacteria share the common precursor glucose-1-phosphate. It is generally assumed that lowering glycogen synthesis could drive more carbon toward sucrose synthesis that can be induced by salt stress among cyanobacteria. By using a theophylline-dependent riboswitch system, the expression of
glgC
, a key gene in glycogen synthesis, was downregulated in a quantitative manner in a sucrose-secreting strain of
Synechococcus elongatus
PCC 7942. We observed that the stepwise suppression of glycogen synthesis limited rather than stimulated sucrose production in the salt-stressed cells, suggesting that glycogen could serve as a carbon pool for the synthesis of sucrose. Accordingly, we generated glycogen-overproducing strains, but the increased glycogen pool alone did not stimulate sucrose production, indicating that alternative steps limit the carbon flux toward the synthesis of sucrose. Consistent with previous studies that showed that sucrose-phosphate synthase (SPS) catalyzes the rate-limiting step in sucrose synthesis, the combination of glycogen overproduction and
sps
overexpression resulted in increased sucrose production. Our results indicate that the glycogen and sucrose pools are closely linked in
Synechococcus elongatus
PCC 7942, and we propose that enhancing the glycogen pool could be a promising strategy for the improvement of sucrose production by cyanobacteria in the presence of a strong sucrose synthesis sink.

IMPORTANCE
Many cyanobacteria naturally synthesize and accumulate sucrose when stressed by NaCl, which provides novel possibilities for obtaining sugar feedstock by engineering of cyanobacteria. It has been assumed that glycogen synthesis competes with sucrose synthesis for the carbon flux. However, our results showed that the suppression of glycogen synthesis decreased rather than stimulated sucrose production in a sucrose-secreting strain of
Synechococcus elongatus
PCC 7942. This result suggests that glycogen could serve as a supportive rather than a competitive carbon pool for the synthesis of sucrose, providing new insights about the relation between glycogen synthesis and sucrose synthesis in cyanobacteria. This finding is also useful to guide metabolic engineering work to optimize the production of sucrose and possibly other products by cyanobacteria.
Porcine Small and Large Intestinal Microbiota Rapidly Hydrolyze the Masked Mycotoxin Deoxynivalenol-3-Glucoside and Release Deoxynivalenol in Spiked Batch Cultures
In Vitro
Authors: Gratz Silvia W. , Currie Valerie , Richardson Anthony J. , Duncan Gary , Holtrop Grietje , Farquharson Freda , Louis Petra , Pinton Philippe , Oswald Isabelle P.
Published: November 2017

Mycotoxin contamination of cereal grains causes well-recognized toxicities in animals and humans, but the fate of plant-bound masked mycotoxins in the gut is less well understood. Masked mycotoxins have been found to be stable under conditions prevailing in the small intestine but are rapidly hydrolyzed by fecal microbiota. This study aims to assess the hydrolysis of the masked mycotoxin deoxynivalenol-3-glucoside (DON3Glc) by the microbiota of different regions of the porcine intestinal tract. Intestinal digesta samples were collected from the jejunum, ileum, cecum, colon, and feces of 5 pigs and immediately frozen under anaerobic conditions. Sample slurries were prepared in M2 culture medium, spiked with DON3Glc or free deoxynivalenol (DON; 2 nmol/ml), and incubated anaerobically for up to 72 h. Mycotoxin concentrations were determined using liquid chromatography-tandem mass spectrometry, and the microbiota composition was determined using a quantitative PCR methodology. The jejunal microbiota hydrolyzed DON3Glc very slowly, while samples from the ileum, cecum, colon, and feces rapidly and efficiently hydrolyzed DON3Glc. No further metabolism of DON was observed in any sample. The microbial load and microbiota composition in the ileum were significantly different from those in the distal intestinal regions, whereas those in the cecum, colon and feces did not differ.

IMPORTANCE
Results from this study clearly demonstrate that the masked mycotoxin DON3Glc is hydrolyzed efficiently in the distal small intestine and large intestine of pigs. Once DON is released, toxicity and absorption in the distal intestinal tract likely occur
in vivo
. This study further supports the need to include masked metabolites in mycotoxin risk assessments and regulatory actions for feed and food.
Fecal Microbiota Transplant from Highly Feed-Efficient Donors Shows Little Effect on Age-Related Changes in Feed-Efficiency-Associated Fecal Microbiota from Chickens
Authors: Siegerstetter Sina-Catherine , Petri Renée M. , Magowan Elizabeth , Lawlor Peadar G. , Zebeli Qendrim , O'Connell Niamh E. , Metzler-Zebeli Barbara U.
Published: November 2017

Chickens with good or poor feed efficiency (FE) have been shown to differ in their intestinal microbiota composition. This study investigated differences in the fecal bacterial community of highly and poorly feed-efficient chickens at 16 and 29 days posthatch (dph) and evaluated whether a fecal microbiota transplant (FMT) from feed-efficient donors early in life can affect the fecal microbiota in chickens at 16 and 29 dph and chicken FE and nutrient retention at 4 weeks of age. A total of 110 chickens were inoculated with a FMT or a control transplant (CT) on dph 1, 6, and 9 and ranked according to residual feed intake (RFI; the metric for FE) on 30 dph. Fifty-six chickens across both inoculation groups were selected as the extremes in RFI (29 low, 27 high). RFI-related fecal bacterial profiles were discernible at 16 and 29 dph. In particular,
Lactobacillus salivarius
,
Lactobacillus crispatus
, and
Anaerobacterium
operational taxonomic units were associated with low RFI (good FE). Multiple administrations of the FMT only slightly changed the fecal bacterial composition, which was supported by weighted UniFrac analysis, showing similar bacterial communities in the feces of both inoculation groups at 16 and 29 dph. Moreover, the FMT did not change the RFI and nutrient retention of highly and poorly feed-efficient recipients, whereas it tended to increase feed intake and body weight gain in female chickens. This finding suggests that host- and environment-related factors may more strongly affect chicken fecal microbiota and FE than the FMT.

IMPORTANCE
Modulating the chicken's early microbial colonization using a FMT from highly feed-efficient donor chickens may be a promising tool to establish a more desirable bacterial profile in recipient chickens, thereby improving host FE. Although FE-associated fecal bacterial profiles at 16 and 29 dph could be established, the microbiota composition of a FMT, when administered early in life, may not be a strong factor modulating the fecal microbiota at 2 to 4 weeks of life and reducing the variation in chicken's FE. Nevertheless, the present FMT may have potential benefits for growth performance in female chickens.
Draft Genome Sequences of 63 Swine-Associated Methicillin-Resistant Staphylococcus aureus Sequence Type 5 Isolates from the United States
Authors: Hau Samantha J. , Bayles Darrell O. , Alt David P. , Frana Timothy S. , Nicholson Tracy L.
Published: November 2017

Methicillin-resistant
Staphylococcus aureus
colonizes humans and other animals such as swine. Livestock-associated methicillin-resistant
Staphylococcus aureus
(LA-MRSA) sequence type 5 (ST5) isolates are a public concern due to their pathogenicity and ability to acquire mobile genetic elements. This report presents draft genome sequences for 63 LA-MRSA ST5 isolates in the United States.
Complete Genome Sequence of Heat-Resistant Newcastle Disease Virus Strain HR09
Authors: Cao Yongzhong , Liu Qian , Zhang Xiaorong , Hu Hai , Wu Yantao
Published: November 2017

In this study, the complete genome sequence of the heat-resistant Newcastle disease virus (NDV) strain HR09, which was isolated in China in the 1990s, was determined and characterized phylogenetically. This is the first report regarding the complete genomic information of a thermostable NDV strain from China.
Genome Sequences of the Mycobacterium tuberculosis H37Rv-
ptkA
Deletion Mutant and Its Parental Strain
Authors: Tsui Clement K. M. , Wong Dennis , Narula Gagandeep , Gardy Jennifer L. , Hsiao William W. H. , Av-Gay Yossef
Published: November 2017

Mycobacterium tuberculosis
, the etiological agent of tuberculosis, is one of the most devastating infectious agents in the world. Here, we report the draft genome sequences of the
M. tuberculosis
protein tyrosine kinase (
ptkA
) deletion mutant and its parental strain H37Rv, which are used in genetic studies and for drug discovery.
Genome Sequence of Piezophilic Bacterium Desulfovibrio profundus Strain 500-1, Isolated from a Deep Sediment Layer in the Japan Sea
Authors: Fouteau Stéphanie , Guerin Thomas , Magdelenat Ghislaine , Roumagnac Marie , Bartoli Manon , Ollivier Bernard , Dolla Alain , Barbe Valérie , Pradel Nathalie
Published: November 2017

Piezophilic
Desulfovibrio profundus
strain 500-1 was isolated in the Japan Sea from a sediment layer at 500-m depth under a water column of 1,000 m. Here, we report the genome sequence of this strain, which includes a 4,168,905-bp circular chromosome and two plasmids of 42,836 bp and 6,167 bp.
Twelve Complete Reference Genomes of Clinical Isolates in the
Capnocytophaga
Genus
Authors: Villarma Aaron , Gulvik Christopher A. , Rowe Lori A. , Sheth Mili , Juieng Phalasy , Nicholson Ainsley C. , Loparev Vladimir N. , McQuiston John R.
Published: November 2017

We report here 1 near-complete genome sequence and 12 complete genome sequences for clinical
Capnocytophaga
isolates. Total read coverages ranged from 211× to 737×, and genome sizes ranged from 2.41 Mb to 3.10 Mb. These genomes will enable a more comprehensive taxonomic evaluation of the
Capnocytophaga
genus.
Whole-Genome Sequence of Escherichia coli Serotype O157:H7 Strain B6914-ARS
Authors: Uhlich Gaylen A. , Reichenberger Erin R. , Cottrell Bryan J. , Fratamico Pina , Andreozzi Elisa
Published: November 2017

Escherichia coli
serotype O157:H7 strain B6914-MS1 is an isolate from the Centers for Disease Control and Prevention that is missing both Shiga toxin genes and has been used extensively in applied research studies. Here we report the genome sequence of strain B6914-ARS, a B6914-MS1 clone that has unique biofilm properties.
Complete Genome Sequence of
Exiguobacterium
sp. Strain N4-1P, a Psychrophilic Bioemulsifier Producer Isolated from a Cold Marine Environment in North Atlantic Canada
Authors: Cai Qinhong , Ye Xudong , Chen Bing , Zhang Baiyu
Published: November 2017

Here, we present the complete genome sequence of
Exiguobacterium
sp. strain N4-1P, a psychrophilic bacterium that produces bioemulsifier, isolated for the first time from petroleum hydrocarbon-contaminated sediment samples from shoreline Newfoundland, Canada. Many strains of the genus
Exiguobacterium
are extremophiles and have properties of biotechnological interest.
Ocular manifestations, complications and management of congenital ichthyoses: a new look
Authors: Malhotra Raman , Hernández-Martın Angela , Oji Vinzenz
Published: November 2017

Congenital ichthyoses (CI) are rare genetic skin keratinisation diseases characterised by generalised scaling and a variable degree of erythema and hyperkeratosis. Ocular involvement includes the eyelids, conjunctiva and all layers of the cornea. Ophthalmic input should include regular slit lamp review with the primary aim to prevent a corneal epithelial defect, secondary bacterial infection, scarring or perforation. This review highlights the current literature regarding ophthalmic findings and management of CI.
Topographic correlation between juxtapapillary choroidal thickness and parapapillary deep-layer microvasculature dropout in primary open-angle glaucoma
Authors: Lee Seung Hyen , Lee Eun Ji , Kim Tae-Woo
Published: November 2017

Purpose

To investigate the topographic relationship between parapapillary deep-layer microvasculature dropout (MvD) as assessed by optical coherence tomography (OCT) angiography (OCTA) and the juxtapapillary choroidal thickness (JPCT) in primary open-angle glaucoma (POAG).

Methods

A total of 194 eyes (138 POAG and 56 control eyes) having parapapillary atrophy (PPA) were imaged using the swept-source OCT and OCTA to examine the microstructure of PPA and measure the JPCT, and to determine the presence of the MvD. MvD was defined as a focal sectoral capillary dropout without any visible microvascular network identified in the parapapillary deep-layer in the en face OCTA images.

Results

JPCT was smaller in the POAG group than control group at 6-, 6.5-, 7- and 7.5-o’clock meridians (all p≤0.002). When POAG eyes were classified into those with parapapillary γ-zone and those with only β-zone without γ-zone, the mean JPCT was significantly smaller in the latter (p=0.027). The JPCT differed between with and without MvD only in eyes with a γ-zone: the JPCT was smaller in the eyes having MvD at 7- and 7.5-o’clock meridians (both p=0.001), where MvD was detected most frequently. However, such a difference was not observed in the eyes with only β-zone without the γ-zone at any of the meridians.

Conclusions

Localised reductions in JPCT were observed at the location of MvD in POAG eyes with parapapillary γ-zone. Such a correlation was not observed in the POAG eyes with only β-zone, but the mean JPCT was significantly smaller in this group.
Concussed elite athletes have better tandem gait performance
Authors: Nabhan Dustin , Walden Taylor , Moreau William J
Published: November 2017

Objective

Describe tandem gait score performance in concussed elite athletes as compared to asymptomatic baselines.

Design

Within subjects, repeated measures.

Setting

United States Olympic Committee Sports Medicine Clinics

Participants

Six hundred forty-one elite athletes (291 women and 350 men, mean age 24.9±5.2 years) representing 23 Olympic sports participated in this study.

Intervention

The SCAT3 was administered during a preseason baseline and repeated as clinically indicated during initial evaluations and serially as part of a multimodal concussion management program.

Outcome measures

SCAT3 performance measures of concussed elite athletes were compared to baseline SCAT3 performance.

Results

Tandem gait performance was significantly better in concussed elite athletes than on athletes tested for healthy asymptomatic baselines (9.6 vs. 11.7, P<0.001), despite concussed athletes reporting significantly higher total number of symptoms (6.4 vs. 2.1, P<0.001) and symptom severity scores (13.1 vs. 3.4, P<0.001) during concussion recovery.

Conclusions

There is a paradoxical relationship between concussion status and tandem gait performance in elite athletes, with concussed athletes performing better on average than athletes evaluated for a baseline SCAT3 evaluation.

Clinical Relevance

Tandem gait performance is not impaired in athletes with symptoms of concussion. Intrinsic motivation to return to play may result in enhanced tandem gait performance in concussed athletes.

Competing interests

None.
Stratification of recovery from concussion using an objective multi-factorial approach to neurocognitive and motor performance assessment
Authors: Linder Susan M , Russman Andrew , Figler Rick , Cruickshank Jason , Grey Bob , Lally Maureen , Dey Tanujit , Alberts Jay L
Published: November 2017

Objective

To characterise neurologic impairment and recovery associated with concussion in youths and young adults using the Cleveland Clinic Concussion application (C3 app).

Design

Retrospective observational study

Setting

Concussion clinic at an academic medical centre

Participants

181 student-athletes aged 14–20 diagnosed with concussion by a Cleveland Clinic physician were included.

Intervention

C3 data were collected pre-season and at least once post-injury. At least one clinical examination by a physician was obtained to characterise clinical impairments. Individuals were stratified into two groups based on recovery time: typical <21 days (n=97) or protracted 21+ days (n=84).

Outcome measures

The following modules of the C3 app were administered across groups: 1) Graded symptom checklist (GSC); 2) Standardised Assessment of Concussion (SAC); 3) Trail Making Test; 4) Simple and Choice Reaction Time; 5) Processing Speed Test; 6) Biomechanical quantification of balance during the BESS.

Main results

At baseline, both groups performed similarly on all modules. However, significant differences were evident at 21 days post-injury in the protracted recovery group with worse performance in: simple and choice reaction time (p<0.001), Trail Making Test B (p=0.01), Biomechanical quantification of BESS (p<0.05), and GSC (p=0.0001). No difference between the groups at 21 days was found in BESS error scores, SAC or processing speed.

Conclusions

An approach that utilises objective and quantitative measures to characterise multiple aspects of neurocognitive and motor function are more sensitive than traditional measures of concussion assessment. These new outcomes provide value in the stratification of patients and their potential time to recovery.

Competing interests

JLA and SML have authored intellectual property associated with the mobile application presented in this study. The remaining authors declare no competing interest.

None.
Changes in measures of cervical, vestibular, dynamic balance and tasks of divided attention following sport-related concussions in elite youth ice hockey players
Authors: Schneider Kathryn J , Palacios-Derflingher Luz , Meeuwisse Willem H , Emery Carolyn A
Published: November 2017

Objective

To evaluate acute changes in measures of cervical spine, vestibulo-ocular reflex (VOR) function, dynamic balance and tasks of divided attention in elite youth ice hockey players following a sport-related concussion.

Study Design

Prospective Case series

Setting

Sport Medicine Centre, Calgary, Alberta, Canada

Participants

Five hundred and fifty-nine (474 males) elite (AA and AAA) Bantam (13-14 years) and Midget (15-17 years) youth ice hockey players.

Outcome measures

Clinical measurements including cervical flexor endurance test (CFE), head perturbation test, head thrust test, dynamic visual acuity (DVA) (clinical and computerised), Functional Gait Assessment (FGA) and Walking While Talking (WWTT) test at baseline and acutely following concussion.

Main results

Sixty-nine of 97 (71%) players completed both baseline and acute post concussion measures for their first concussion and were included in these analyses. Following concussion, neck pain, headache and dizziness increased in 42%, 58% and 40% of participants respectively. After Bonferroni corrections (α=0.00625), using Wilcoxon Signed-Rank Test, cervical spine measures were significantly worse following concussion compared to baseline [cervical flexor endurance test (z=−5.195, p<0.001) and head perturbation test (z=−4.631, p<0.001)]. Time to complete a complex task of divided attention (WWTT) relative to their normal walking speed was longer than baseline (z=−2.762, p=0.0057). There was no change in DVA or FGA following concussion.

Conclusions

Measures of cervical spine function and tasks of divided attention were worse following concussion. However, tests of VOR and dynamic balance were not significantly different than at baseline. Future research to evaluate the mechanism underlying these changes is warranted.

Competing interests

None.
Concussion in the emergency department; unconsciously incompetent?
Authors: Phillips Thom , Guy Katie , Martin Rhodri , Tomkinson Alicia , Phillips Dan , Sloane Nicole
Published: November 2017

Objective

Sports related concussion is an increasingly common occurrence. Outside professional sport it is typically managed within Emergency Departments. The objective was to assess the level of knowledge and understanding of UK emergency medicine doctors of concussion; it’s recognition, diagnosis and management.

Design

Cross-sectional observational study using self-report questionnaires.

Setting

Questionnaires were distributed at regional EM conferences between October 2015 and January 2016. 15 secondary and 5 tertiary care centres were represented.

Participants

156 questionnaires were completed. Illegible answers, defaced or incorrectly completed questionnaires were discarded. 134 were included in the analysis. Training levels represented were: Consultant (10%), Specialist Registrar (12%), Staff Grade (5%), Core Trainee (34%), Foundation Trainee (20%), Emergency Nurse Practitioners (1.5%), Medical Students (16%).

Interventions (or Assessment of Risk Factors)

The questionnaire asked respondents to correctly identify signs and symptoms of concussion according to the Zurich consensus statement. It asked whether there were differences in the management of adult and paediatric concussion together with questions regarding RTP guidelines and use of potentially protective equipment.

Main results

Consultants obtained the highest signs and symptoms score (6.2). The least correct were Specialist Registrars (2.0). Diagnostic accuracy did not differ between secondary and tertiary centres (p=0.67). 80% of participants incorrectly identified headguards as being protective against concussion. 35.4% of respondents acknowledged a difference between adult and paediatric concussion.

Conclusions

This small yet representative sample highlights a lack of knowledge in concussion in health professionals working in EDs in the UK. Efforts to improve the knowledge and understanding of concussion are required given the increasing awareness of the impact and occurrence of sports concussion.

Competing interests

None.
Differences in symptom severity and gait balance deficit in concussed adolescents with and without concussion history
Authors: Chou Li-Shan , Peterson Quinn , Osternig Louis
Published: November 2017

Objective

There is conflicting evidence on whether a prior concussion is associated with a prolonged recovery course. This study was aimed to examine the effect of concussion history on recovery of symptoms and gait balance control in adolescents.

Design

A prospective, repeated-measures design was employed. Subject were assessed within 72 hours of sustaining a concussion and at 2, 4, and 8 weeks post-injury.

Settings

University research laboratory

Participants

High school student athletes with concussion injury

Outcome measures

Symptoms resulting from the injury were assessed using a 22 symptom inventory adapted from the Standardised Concussion Assessment Tool. Dual-task gait testing was employed to examine how divided attention affects balance control following concussion. Comparisons between subjects with and without concussion history were made for dependent variables of symptom scores and medial-lateral motion of the center-of-mass.

Main Results

A total of 31 concussed adolescents were tested, 9 of them had 1 or 2 diagnosed concussions more than 12 months prior to the current injury. Four subjects without concussion history and 4 subjects with concussion history were not permitted to resume normal physical activities within our 2-month study period. Subjects with concussion history displayed significantly elevated symptom scores during the first two weeks of recovery and displayed greater gait instability during the first month of recovery when compared to subjects without concussion history.

Conclusions

These preliminary findings indicate that previous concussion, more than one year prior to the current injury, could affect deficit severity and length of recovery.

Competing interests

The authors have no conflicts of interest to declare.
Effect of concussion history on sway velocity and bess scores in division i football players
Authors: Miyashita Theresa , Batchelder Benson
Published: November 2017

Objective

The purpose of our study was to investigate if concussion history has an effect on sway velocity and BESS scores in Division I football players.

Design

Cohort Study

Setting

Division I University

Participants

75 Division I football players (age=19.76 ± 1.1, height=72.41” ± 2.19”, weight=222.55 lbs ± 38.17 lbs)

Outcome measures

Correlation statistics determined the association between concussion history, sway velocity, and BESS errors. Sway velocity was determined by performing the BESS test on a force plate, and BESS errors were determined by one experienced evaluator. Players performed the six trials of the BESS test: three stances on two surfaces.

Main results

There were no statistical associations between concussion history and sway velocity or BESS errors. There were significant and positive correlations between sway velocity and BESS errors, indicating as sway velocity increased so did the number of errors, on the following trials: single leg firm surface (rs=0.62,p<0.001), tandem stance firm surface (rs=0.72,p?< 0.001), single leg foam surface (rs=0.25,p=0.029), tandem stance foam surface (rs=0.70,p<0.001), and composite scores (rs=0.68,p<0.001).

Conclusions

Concussion history does not appear to have an impact on sway velocity measures or BESS scores. However, there was a significant and positive correlation between sway velocity and BESS errors during four of the trials and the composite scores, supporting the validity of the BESS test.

Competing interests

None.
Exposure to injury in mixed-martial-arts is associated with evidence of concussion injury
Authors: Neville Christopher , Johnson Paul , Baracks Joshua , Rieger Brian
Published: November 2017

Objective

The purpose of this study was to determine if exposure to injury during mixed-martial-arts (MMA) fights is associated with concussion injury. It was hypothesised that number of hits-to-the-head (HTH) would be associated with concussion assessment findings.

Design

Case-series

Setting

Amateur MMA fighters agreed to complete the testing at training facilities and fight venues.

Participants

A convenience sample 33 MMA fighters completed pre and post-fight assessments (32 males, 1 female)

Interventions (or Assessment of Risk Factors)

The independent variable was group assignment. The low-exposure (LE) group (n=17) had a mean of 5.8±5.9 HTH while the high-exposure (HE) group (n=16) had a mean of 34.0±9.8 HTH.

Outcome measures

The dependent variables were compared using an ANOVA model. They included: average speed to complete the Tails B cognitive test, balance measured with an inertial measurement unit, S100B protein concentration in blood serum, and self-reported symptoms.

Main results

The change in S100B concentration from pre to post-fight was significantly greater (p=0.01) in the HE group (0.22±0.14 ug/L) compared to the LE group (0.10±0.11 ug/L). Dual-task balance cost was significantly greater (p=0.02) in the HE group (0.04±0.05 m/s2/Hz) compared to the LE (0.01±0.01 m/s2/Hz) group. No difference in Trails B speed or self-reported symptoms was observed.

Conclusions

The increase in S100B concentration in the peripheral blood and changes in balance performance suggest concussion injuries are common during MMA fights but injuries are associated with exposure to head impacts. Cognitive tests and symptom report may not be as sensitive to injury.

Competing interests

Dr. Neville: Ongoing research sponsorship and equity interest in Motion Intelligence Inc. who provided the hardware for some of the concussion screening used in this study.

Dr. Johnson: None.

Mr. Baracks: None.

Dr. Rieger: Ongoing research sponsorship and equity interest in Motion Intelligence Inc. who provided the hardware for some of the concussion screening used in this study.
Multi-disciplinary management of paediatricpediatric sports-related concussion: early experience of the pan am concussion program
Authors: Russell Kelly , Ritchie Lesley , McDonald Patrick J , Cordingley Dean , Reimer Karen , Girardin Richard , Vis Sara , Selci Erin , MacDonald Peter , Leiter Jeffrey , Ellis Michael
Published: November 2017

Objective

Summarise clinical characteristics, outcomes, and healthcare resources and personnel needs of paediatric sports-related concussion (SRC) patients who were evaluated and managed at a multi-disciplinary paediatric concussion program.

Design

Retrospective cohort study

Setting

Paediatric, multi-disciplinary concussion clinic

Participants

423 paediatric SRC patients: 14.3 years (SD: 2.3), 59.6% males, 43.0% hockey-related, and 75.8% acute SRC

Interventions (or assessment of risk factors)

Initial assessment and diagnosis by a neurosurgeon with the multi-disciplinary team completing Return-to-Play decision-making. On-site neurosurgeon, neuropsychologist, vestibulo-ocular therapist, and exercise physiologist and referrals to neurology and psychiatry

Outcome measures

SRC diagnosis and recovery were defined by the 2013 Zurich Consensus Guidelines. Post-Concussion Syndrome was diagnosed using ICD-10 criteria of at least 3 symptoms at 30 days or more. Outcomes included demographic and injury data, healthcare resources and personnel utilised, and recovery

Main results

Overall, 294 (69.5%) of SRC patients met the clinical criteria for recovery, 75 (17.7%) were lost to follow-up, 53 (12.5%) remained in treatment, and 1 died (0.2%). In acute patients, median time to initial consultation was 7 days (IQR: 5, 12). Median days to recovery among acute SRC patients with complete follow-up was 23 days (IQR: 15, 36) and 44.1% of acute SRC patients were diagnosed with PCS. 25.3% of SRC patients underwent at least one diagnostic imaging test and 32.6% received referral to another member of our multi-disciplinary clinical team.

Conclusions

Youth received comprehensive care with access to appropriate diagnostic resources and multi-disciplinary collaboration of experts with national and provincially-recognised training in TBI

Competing interests

None.
Pilot study of knowledge and management of concussion in emergency department doctors in singapore
Authors: Probert Joanne , Sirisena Dinesh , Walter Joy
Published: November 2017

Objective

1. To gain an understanding of Singapore Emergency Physicians (EPs) knowledge and practice habits when assessing concussions in the Emergency Department (ED).

2. To determine what knowledge exists regarding current international concussion management and return-to-play guidelines

Design

A 21 item anonymous internet survey was developed and disseminated to EPs in Singapore. A limited time period for completion was given. Because of anonymity, non-responders could not be specifically targeted. Participation was voluntary and no incentives were offered.

Results

26 responses which included 9 Associate Consultants or above, 4 Registrars, 14 junior doctors. 63% were Singapore trained.

88.9% were aware of the concussion diagnosis but only 50% could document the salient points required to diagnose concussion.

The highest percentage (33.3%) reported seeing cases of concussion monthly, 18.5% fortnightly, 29.6% weekly and 14.8% daily. 33.3% of EPs were aware of Internationally Recognised guidelines but only 11% use them.

70.4% refer concussions for follow up (47.4% to Neurosurgery and 21.1% to Sports Medicine). Only 14.8% of EPs have had specific training in sports concussion management.

Conclusions

1. It is likely that concussion is under diagnosed; many EPs only report seeing cases monthly and are unaware of the salient features to diagnose concussion.

2. International guidelines regarding return-to-play and standardised assessment have not reached the majority of EPs.

3. A small proportion of concussion cases are referred to Sports Clinics for follow up.

4. Further training in sports concussion management in Singapore EDs is needed.

5. Further studies in this area are required.

Competing interests

Joanne Probert – Trainer for World Rugby.