bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Modeling and Locomotion Control for Quadruped Robots Based on Center of Inertia on SE(3)
Authors: Ding Xilun , Chen Hao
Published: October 2015

Quadruped robots have good mobility and agility in complex environments, but dynamic control of locomotion for quadruped robots has long been a big challenge for researchers. In this paper, we build the center of inertia (COI) dynamic model of a general quadruped robot and give the exponential coordinates of COI on the special Euclidean space SE(3). The COI model takes the whole quadruped robot as one body, so that the only concern is the movement of the COI rather than the body or legs when the robot walks. As a result, the COI model has fewer dimensions of state variables than the full dynamic model, which helps to reduce the computational load. A control method for quadruped robots is presented based on the dynamic model which is constituted of force loop and position loop. This method controls the movement of the COI directly, so it facilitates to guarantee the robot's stability. The virtual body of the quadruped robot is defined to describe the configuration of the quadruped robot. The proportional-derivative (PD) control method on SE(3) is applied to control the movement of the virtual body, which makes the movement more in line with the group theoretic viewpoint. Finally, some simulation experiments have been conducted to verify the validity of our method.
Friction Reduction in Lubricated Rough Contacts: Numerical and Experimental Studies
Authors: Liu Zhiqiang , Gangopadhyay Arup
Published: October 2015

Combining the contact model of elastic-layered solid with the concept of asperity contact in elastohydrodynamic lubrication (EHL), a mixed-lubrication model is presented to predict friction coefficient over rough surfaces with/without an elastic-layered medium under entire lubrication regimes. Solution of contact problems for elastic-layered solids is presented based upon the classical model of Greenwood and Williamson (GW) in conjunction with Chen and Engel's analysis. The effects of the Young's modulus ratio of the layer to substrate and the thickness of the layer on the elastic real area of contact and contact load for a fixed dimensionless separation are studied using the proposed method, which is used for the asperities having contact with an elastic coating. Coefficient of friction with elastic-layered solids in boundary lubrication is calculated in terms of Rabinowicz's findings and elastic-layered solutions of Gupta and Walowit. The effect of rough contacts with an elastic layer on friction coefficient in lubrication regimes has been analyzed. Variations in plasticity index ψ significantly affect friction coefficients in boundary and mixed lubrications. For a large value of ψ, the degree of plastic contact exhibits a stronger dependence of the mean separation or film thickness than the roughness, and for a small value of ψ, the opposite result is true. The effect of governing parameters, such as inlet oil viscosity at ambient pressure, pressure–viscosity coefficient, combined surface roughness, and El/E2 on friction coefficient, has been investigated. Simulations are shown to be in good agreement with the experimental friction data.
Oil Whip Elimination Using Fuzzy Logic Controller
Authors: Dimitri A. S. , Mahfoud J. , El-Shafei A.
Published: October 2015

Oil whip is a self-excited subsynchronous vibration which limits the range of operating speed of journal bearings (JBs). JBs have wide range of applications due to their high loading capacity, simple geometry, and lubrication. When the speed of rotation increases, the oil whip instability is excited with a frequency corresponding to the rotor critical speed which causes excessive undesirable vibration. A solution for this instability is implemented through this paper. The control action is implemented through a new integrated bearing device. The bearing consists of JB and electromagnetic actuator (EMA). The oil whip control action is applied through the EMA. A fuzzy logic control algorithm is developed and experimentally applied to a rotor test rig. The controller is suitable to deal with the problems of uncertainties and nonlinearity. The experimental results show the ability of the developed controller to eliminate the oil whip instability when applied to a test rig which simulates industrial rotor through an integrated bearing prototype which was designed and manufactured.
Needle detection in curvilinear ultrasound images based on the reflection pattern of circular ultrasound waves
Authors: Daoud Mohammad I. , Rohling Robert N. , Salcudean Septimiu E. , Abolmaesumi Purang
Published: October 2015

Purpose:

Ultrasound imaging provides a low‐cost, real‐time modality to guide needle insertion procedures, but localizing the needle using conventional ultrasound images is often challenging. Estimating the needle trajectory can increase the success rate of ultrasound‐guided needle interventions and improve patient comfort. In this study, a novel method is introduced to localize the needle trajectory in curvilinear ultrasound images based on the needle reflection pattern of circular ultrasound waves.

Methods:

A circular ultrasound wave was synthesized by sequentially firing the elements of a curvilinear transducer and recording the radio‐frequency signals received by each element. Two features, namely, the large amplitude and repetitive reflection pattern, were used to identify the needle echoes in the received signals. The trajectory of the needle was estimated by fitting the arrival times of needle echoes to an equation that describes needle reflection of circular waves. The method was employed to estimate the trajectories of needles inserted in agar phantom, beef muscle, and porcine tissue specimens.

Results:

The maximum error rates of estimating the needle trajectories were on the order of 1 mm and 3° for the radial and azimuth coordinates, respectively.

Conclusions:

These results suggest that the proposed method can improve the robustness and accuracy of needle segmentation methods by adding signature‐based detection of the needle trajectory in curvilinear ultrasound images. The method can be implemented on conventional ultrasound imaging systems.
Technical Note: Fabricating Cerrobend grids with 3D printing for spatially modulated radiation therapy: A feasibility study
Authors: Zhu Xiaofeng , Driewer Joseph , Li Sicong , Verma Vivek , Lei Yu , Zhang Mutian , Zhang Qinghui , Zheng Dandan , Cullip Timothy , Chang Sha X. , Wang Andrew Z. , Zhou Sumin , Enke Charles A.
Published: October 2015

Purpose:

Grid therapy has promising applications in the radiation treatment of large tumors. However, research and applications of grid therapy are limited by the accessibility of the specialized blocks that produce the grid of pencil‐like radiation beams. In this study, a Cerrobend grid block was fabricated using the 3D printing technique.

Methods:

A grid block mold was designed with flared tubes which follow the divergence of the beam. The mold was 3D printed using a resin with the working temperature below 230 °C. The melted Cerrobend liquid at 120 °C was cast into the resin mold to yield a block with a thickness of 7.4 cm. At the isocenter plane, the grid had a hexagonal pattern, with each pencil beam diameter of 1.4 cm; the distance between the beam centers was 2.1 cm.

Results:

The dosimetric properties of the grid block were studied using small field dosimeters: a pinpoint ionization chamber and a stereotactic diode. For a 6 MV photon beam, its valley‐to‐peak ratio was 20% at dmax and 30% at 10 cm depth; the output factor was 84.9% at dmax and 65.1% at 10 cm depth.

Conclusions:

This study demonstrates that it is feasible to implement 3D printing technique in applying grid therapy in clinic.
A new technique to characterize CT scanner bow‐tie filter attenuation and applications in human cadaver dosimetry simulations
Authors: Li Xinhua , Shi Jim Q. , Zhang Da , Singh Sarabjeet , Padole Atul , Otrakji Alexi , Kalra Mannudeep K. , Xu X. George , Liu Bob
Published: October 2015

Purpose:

To present a noninvasive technique for directly measuring the CT bow‐tie filter attenuation with a linear array x‐ray detector.

Methods:

A scintillator based x‐ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X‐Scan 0.8c4‐307, Detection Technology, FI‐91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field‐of‐view. The sampling time was as short as 0.24 ms. To measure the body bow‐tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x‐ray tube was parked at the 12 o'clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow‐tie in the beam path. Each readout signal was corrected for the detector background offset and signal‐level related nonlinear gain, and the ratio of the two exposures gave the bow‐tie attenuation. The results were used in the geant4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x‐ray tube starting angles.

Results:

Absolute attenuation was measured with the body bow‐tie scanned at 80–140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively.

Conclusions:

The described method allows fast and accurate bow‐tie filter characterization.
A test of deep water Rytov theory at 284 Hz and 107 km in the Philippine Sea
Authors: Andrew Rex K. , White Andrew W. , Mercer James A. , Dzieciuch Matthew A. , Worcester Peter F. , Colosi John A.
Published: October 2015

Predictions of log-amplitude variance are compared against sample log-amplitude variances reported by White, Andrew, Mercer, Worcester, Dzieciuch, and Colosi [J. Acoust. Soc. Am. 134, 3347–3358 (2013)] for measurements acquired during the 2009 Philippine Sea experiment and associated Monte Carlo computations. The predictions here utilize the theory of Munk and Zachariasen [J. Acoust. Soc. Am. 59, 818–838 (1976)]. The scattering mechanism is the Garrett–Munk internal wave spectrum scaled by metrics based on measured environmental profiles. The transmitter was at 1000 m depth and the receivers at nominal range 107 km and depths 600–1600 m. The signal was a broadband m-sequence centered at 284 Hz. Four classes of propagation paths are examined: the first class has a single upper turning point at about 60 m depth; the second and third classes each have two upper turning points at roughly 250 m; the fourth class has three upper turning points at about 450 m. Log-amplitude variance for all paths is predicted to be 0.04–0.09, well within the regime of validity of either Born or Rytov scattering. The predictions are roughly consistent with the measured and Monte Carlo log-amplitude variances, although biased slightly low. Paths turning in the extreme upper ocean (near the mixed layer) seem to incorporate additional scattering mechanisms not included in the original theory.
Characterization of immersed transversely isotropic rods by inversion of acoustic scattering data
Authors: Kari Mohammadreza , Honarvar Farhang
Published: October 2015

An ultrasonic technique is proposed for measurement of the elastic constants of a transversely isotropic cylindrical sample. This technique can measure all five elastic constants of a transversely isotropic rod or fiber nondestructively. The immersed rod is insonified first by a normally incident, and then by an obliquely incident, ultrasonic wave and the backscattered pressure amplitude spectra, form functions, are measured. The elastic constants of the transversely isotropic cylindrical sample are then extracted from these form functions by an inversion process. The inversion process is based on a genetic algorithm and matches a theoretical model to the measured form functions at resonance points. The proposed approach is simple and very accurate.
Using Bar Velocity to Predict Maximum Dynamic Strength in the Half-Squat Exercise
Authors: Loturco Irineu , Pereira Lucas A. , Abad Cesar C. Cal , Gil Saulo , Kitamura Katia , Kobal Ronaldo , Nakamura Fábio Y.
Published: October 2015

Purpose:

To determine whether athletes from different sport disciplines present similar mean propulsive velocity (MPV) in the half-squat (HS) during submaximal and maximal tests, enabling prediction of 1-repetition maximum (1-RM) from MPV at any given submaximal load.

Methods:

Sixty-four male athletes, comprising American football, rugby, and soccer players; sprinters and jumpers; and combat-sport strikers attended 2 testing sessions separated by 2–4 wk. On the first visit, a standardized 1-RM test was performed. On the second, athletes performed HSs on Smith-machine equipment, using relative percentages of 1-RM to determine the respective MPV of submaximal and maximal loads. Linear regression established the relationship between MPV and percentage of 1-RM.

Results:

A very strong linear relationship (R2 ≈ .96) was observed between the MPV and the percentages of HS 1-RM, resulting in the following equation: %HS 1-RM = −105.05 × MPV + 131.75. The MPV at HS 1-RM was ~0.3 m/s.

Conclusion:

This equation can be used to predict HS 1-RM on a Smith machine with a high degree of accuracy.
Student (Dis)Engagement and Need-Supportive Teaching Behavior: A Multi-Informant and Multilevel Approach
Authors: Van den Berghe Lynn , Tallir Isabel B. , Cardon Greet , Aelterman Nathalie , Haerens Leen
Published: October 2015

Starting from self-determination theory, we explored whether student engagement/disengagement relates to teachers’ need support and whether this relationship is moderated by teachers’ causality orientations. A sample of 2004 students situated in 127 classes taught by 33 physical education teachers participated in the study. Both teachers and students reported on students’ (dis)engagement, allowing investigation of the proposed relationships both at the student and teacher level. Most of the variance in need support was at the student level, but there was also between-teacher and between-class variance in need support. Engagement related to more need support, but only at the student level. In total, few moderation effects were found. Teachers with a relatively low controlled orientation were more need supportive when perceiving their students as emotionally and behaviorally engaged. By making teachers aware of these dynamics, automatic responses to student engagement can be better thought out. Recommendations for future research are discussed.
Dealing With Negative Stereotypes in Sports: The Role of Cognitive Anxiety When Multiple Identities Are Activated in Sensorimotor Tasks
Authors: Martiny Sarah E. , Gleibs Ilka H. , Parks-Stamm Elizabeth J. , Martiny-Huenger Torsten , Froehlich Laura , Harter Anna-Lena , Roth Jenny
Published: October 2015

Based on research on stereotype threat and multiple identities, this work explores the beneficial effects of activating a positive social identity when a negative identity is salient on women’s performance in sports. Further, in line with research on the effects of anxiety in sports, we investigate whether the activation of a positive social identity buffers performance from cognitive anxiety associated with a negative stereotype. Two experiments tested these predictions in field settings. Experiment 1 (N = 83) shows that the simultaneous activation of a positive (i.e., member of a soccer team) and a negative social identity (i.e., woman) led to better performance than the activation of only a negative social identity for female soccer players. Experiment 2 (N = 46) demonstrates that identity condition moderated the effect of cognitive anxiety on performance for female basketball players. Results are discussed concerning multiple identities’ potential for dealing with stressful situations.
Bayesian Structural Equation Modeling in Sport and Exercise Psychology
Authors: Stenling Andreas , Ivarsson Andreas , Johnson Urban , Lindwall Magnus
Published: October 2015

Bayesian statistics is on the rise in mainstream psychology, but applications in sport and exercise psychology research are scarce. In this article, the foundations of Bayesian analysis are introduced, and we will illustrate how to apply Bayesian structural equation modeling in a sport and exercise psychology setting. More specifically, we contrasted a confirmatory factor analysis on the Sport Motivation Scale II estimated with the most commonly used estimator, maximum likelihood, and a Bayesian approach with weakly informative priors for cross-loadings and correlated residuals. The results indicated that the model with Bayesian estimation and weakly informative priors provided a good fit to the data, whereas the model estimated with a maximum likelihood estimator did not produce a well-fitting model. The reasons for this discrepancy between maximum likelihood and Bayesian estimation are discussed as well as potential advantages and caveats with the Bayesian approach.
Changes in Task Self-Efficacy and Emotion Across Competitive Performances in Golf
Authors: Boardley Ian D. , Jackson Ben , Simmons Alexander
Published: October 2015

This research aimed to investigate (a) the effect of golfers’ perceptions of coach motivation efficacy on golfers’ precompetition task self-efficacy, (b) the effect of performance on pre-to-postround changes in self-efficacy, (c) the effect of pre-to-postround changes in self-efficacy on pre-to-postround changes in affect and emotion, and (d) whether any effects of performance on pre-to-postcompetition changes in affect and emotion were mediated by pre-to-postcompetition changes in self-efficacy. In Study 1, a scale measuring golf self-efficacy was developed and validated using data from 197 golfers. In Study 2, 200 golfers completed this measure alongside measures of coach motivation efficacy, and positive and negative affect before a golf competition; all measures (except coach motivation efficacy) were again completed following the competition. Structural equation modeling showed that coach motivation efficacy positively predicted precompetition self-efficacy, performance positively predicted pre-to-postcompetition changes in self-efficacy, which had positive and negative effects, respectively, on pre-to-postcompetition changes in positive and negative affect; mediation analyses demonstrated that pre-to-postcompetition changes in self-efficacy mediated effects of performance on pre-to-postcompetition changes in positive and negative affect. In Study 3, the Study-2 procedures were replicated with a separate sample of 212 golfers, except measures of excitement, concentration disruption, somatic anxiety, and worry replaced those for positive and negative affect. Structural analyses showed the findings from Study 2 were largely replicated when specific emotions were investigated in place of general indices of affect. This investigation makes novel contributions regarding the potential importance of perceptions of coach efficacy for golfers’ own efficacy beliefs, and the role personal efficacy beliefs may play in facilitating the effects of performance on affective outcomes.
Things We Still Haven’t Learned (So Far)
Authors: Ivarsson Andreas , Andersen Mark B. , Stenling Andreas , Johnson Urban , Lindwall Magnus
Published: October 2015

Null hypothesis significance testing (NHST) is like an immortal horse that some researchers have been trying to beat to death for over 50 years but without any success. In this article we discuss the flaws in NHST, the historical background in relation to both Fisher’s and Neyman and Pearson’s statistical ideas, the common misunderstandings of what p < 05 actually means, and the 2010 APA publication manual’s clear, but most often ignored, instructions to report effect sizes and to interpret what they all mean in the real world. In addition, we discuss how Bayesian statistics can be used to overcome some of the problems with NHST. We then analyze quantitative articles published over the past three years (2012–2014) in two top-rated sport and exercise psychology journals to determine whether we have learned what we should have learned decades ago about our use and meaningful interpretations of statistics.
Guardian gone wild
Authors: Nalepa Grzegorz
Published: October 2015

Gain-of-function p53 mutants promote cancer by disrupting chromatin structure and altering expression of target genes.
Draft Genome Sequence of
Bacteroidales
Strain TBC1, a Novel Isolate from a Methanogenic Wastewater Treatment System
Authors: Tourlousse Dieter M. , Matsuura Norihisa , Sun Liwei , Toyonaga Mayu , Kuroda Kyohei , Ohashi Akiko , Cruz Rodrigo , Yamaguchi Takashi , Sekiguchi Yuji
Published: October 2015

We report here the draft genome sequence of
Bacteroidales
strain TBC1, isolated from a methanogenic wastewater treatment system. The draft genome has a size of 4,514,407 bp and a G+C content of 46.7%. The predicted genomic content provides the basis for characterizing the metabolism and ecological strategies of strain TBC1.
Complete Genome Sequence of
Elizabethkingia
sp. BM10, a Symbiotic Bacterium of the Wood-Feeding Termite
Reticulitermes speratus
KMT1
Authors: Lee Dongmin , Kim Young-Kyoon , Kim Yeong-Suk , Kim Tae-Jong
Published: October 2015

Elizabethkingia
sp. BM10 was isolated from the hindgut of the wood-feeding termite
Reticulitermes speratus
KMT1. It had cellobiohydrolase and β-glucosidase activities but not endo-β-glucanase activity. The complete sequence of its genome, which has a total size of 4,242,519 bases, is reported here. The genomic analysis identified six β-glucosidase candidate genes and three β-glucanase candidate genes.
HIV Inhibition by Lactobacilli: Easier in a Test Tube Than in Real Life
Authors: Witkin Steven S. , Linhares Iara M.
Published: October 2015

A lactobacillus-dominant vaginal microbiota has been shown to decrease heterosexual HIV transmission. Nunn et al. now report that a vaginal microbiota dominated by
Lactobacillus crispatus
is associated with a relative inability of HIV pseudoviral particles to transverse cervicovaginal mucus (CVM)
in vitro
[mBio 6(5):e01084-15, 2015, doi:10.1128/mBio.01084-15]. The purported inhibitory mechanism is the interaction between carboxyl groups present on HIV and in CVM that occurred only under acidic conditions when carboxyl groups were protonated.
L. crispatus
produces high levels of lactic acid and results in the lowest vaginal pH when it is the dominant vaginal bacterium. In addition, high levels of lactic acid inhibit the proliferation of other bacteria that might negatively affect CVM structure. The utility of enhancing
L. crispatus
dominance to inhibit HIV transmission awaits assessment of the influence of ejaculated semen on this property and investigations on the role of
Lactobacillus
products such as
d
-lactic acid in this property.
Phaeochromocytoma with hypercortisolism and hypercalcaemia
Authors: Edafe Ovie , Webster Jonathan , Fernando Malee , Vinayagam Ragu , Balasubramanian Sabapathy P
Published: October 2015

We report a case of phaeochromocytoma associated with hypercortisolism and hypercalcaemia in a 62-year-old man. The patient presented to clinic, with a 3-year history of exertional headaches, and a 4-month history of increasing fatigue, sweating and palpitations, loss of appetite and weight, and sleepiness. He did not have a medical, family or social history that could account for these symptoms. 24 h urinary catecholamines, plasma metanephrines, 24 h urinary cortisol and adjusted serum calcium, were elevated. Overnight low-dose dexamethasone suppression test did not suppress morning plasma cortisol. Serum intact parathyroid hormone and parathyroid hormone-related peptide were low, and adrenocorticotropic hormone was normal. The patient was treated with intravenous 0.9% sodium chloride and disodium pamidronate to control hypercalcaemia. CT showed a 10 cm left adrenal mass. Following inpatient treatment with phenoxybenzamine, he underwent a left adrenectomy and histology confirmed a phaeochromocytoma. Postoperatively, he required long-term steroids for contralateral adrenal suppression. Adjusted serum calcium returned to normal postoperatively.
A rare infectious cause of severe neonatal skin lesions
Authors: Demeulemeester Veronique , Voeten Michiel , Jacquemyn Yves , Mahieu Ludo
Published: October 2015

We present a case of a preterm infant of 28 weeks’ gestation with unique cutaneous lesions characteristic of a congenital herpes simplex virus (HSV) type 1 infection. The infant was prematurely delivered due to intractable labour. The mother had no history or clinical signs of genital infection before or during pregnancy. The infant's skin lesions were described as rough white-yellow plaques; a skin biopsy demonstrated calcified plaques and absent epidermis. HSV type 1 was later determined using PCR on the infant's skin biopsy and cerebral spinal fluid as well as the mother's vaginal swab and the placenta. Calcifications have already been described by Alleeet al, alongside a diagnosis of HSV type 2. As is well known, the morbidity and mortality of congenital herpes infections are very high.
Coexistent osteoporosis and multiple myeloma: when to investigate further in osteoporosis
Authors: Wan Elizabeth Rose , Raffles Suzanne , Reynolds Piero
Published: October 2015

Osteoporosis commonly causes vertebral collapse fractures. We present a patient with multiple vertebral fractures in the context of severe osteoporosis, who, in the course of investigation for intractable spine and hip pain, was found to have an IgA myeloma. At 2 months post diagnosis, she was discharged home to continue outpatient chemotherapy.
Hypoplasia of the inferior vena cava in a young man presenting with extensive deep venous thrombosis
Authors: Alderman Bryony Eloise Pfyffer , de Boisanger James , Bottomley Thomas
Published: October 2015

We present a case of a 34-year-old man with extensive deep venous thrombosis (DVT) who was found to have multiple abnormalities of venous anatomy, notably hypoplasia of the inferior vena cava with azygous continuation. DVT has an annual incidence of around 1 in 1000 people in the UK. Many cases will have readily identifiable risk factors, such as underlying malignancy, immobility or thrombophilia, but at times, these might not be so straightforward and unexpected contributing factors may be found. Although relatively uncommon in the general population, congenital venous abnormalities have been found at higher incidence in young adults presenting with spontaneous DVT and should therefore remain a consideration when classical risk factors are absent.
Severe sepsis in women with group BStreptococcusin pregnancy: an exploratory UK national case–control study
Authors: Kalin Asli , Acosta Colleen , Kurinczuk Jennifer J , Brocklehurst Peter , Knight Marian
Published: October 2015

Objective

To estimate the incidence of severe maternal sepsis due to group BStreptococcus(GBS) in the UK, and to investigate the associated outcomes for mother and infant.

Design

National case–control study.

Setting

All UK consultant-led maternity units.

Participants

30 women with confirmed or suspected severe GBS sepsis, and 757 control women.

Main outcome measures

Disease incidence, additional maternal morbidity, critical care admission, length of stay, infant infection, mortality.

Results

The incidences of confirmed and presumed severe maternal GBS sepsis were 1.00 and 2.75 per 100 000 maternities, respectively, giving an overall incidence of 3.75 per 100 000. Compared with controls, severe GBS sepsis was associated with higher odds of additional maternal morbidity (OR 12.35, 95% CI 3.96 to 35.0), requiring level 2 (OR 39.3, 95% CI 16.0 to 99.3) or level 3 (OR 182, 95% CI 21.0 to 8701) care and longer hospital stay (median stay in cases and controls was 7 days (range 3–29 days) and 2 days (range 0–16 days), respectively, p<0.001). None of the women died. Severe maternal GBS sepsis was associated with higher odds of infant sepsis (OR 32.7, 95% CI 8.99 to 119.0); 79% of infants, however, did not develop sepsis. There were no associated stillbirths or neonatal deaths.

Conclusions

Severe maternal GBS sepsis is a rare occurrence in the UK. It is associated with adverse maternal and neonatal outcomes.
Impact of anaemia on lung function and exercise capacity in patients with stable severe chronic obstructive pulmonary disease
Authors: Guo Jian , Zheng Cong , Xiao Qiang , Gong Sugang , Zhao Qinhua , Wang Lan , He Jing , Yang Wenlan , Shi Xue , Sun Xingguo , Liu Jinming
Published: October 2015

Objective

This study intended to search for potential correlations between anaemia in patients with severe chronic obstructive pulmonary disease (COPD; GOLD stage III) and pulmonary function at rest, exercise capacity as well as ventilatory efficiency, using pulmonary function test (PFT) and cardiopulmonary exercise testing (CPET).

Setting

The study was undertaken at Shanghai Pulmonary Hospital, a tertiary-level centre affiliated to Tongji University. It caters to a large population base within Shanghai and referrals from centres in other cities as well.

Participants

157 Chinese patients with stable severe COPD were divided into 2 groups: the anaemia group (haemoglobin (Hb) <12.0 g/dL for males, and <11 g/dL for females (n=48)) and the non-anaemia group (n=109).

Primary and secondary outcome measures

Arterial blood gas, PFT and CPET were tested in all patients.

Results

(1) Diffusing capacity for carbon monoxide (DLCO) corrected by Hb was significantly lower in the anaemia group ((15.3±1.9) mL/min/mm Hg) than in the non-anaemia group ((17.1±2.1) mL/min/mm Hg) (p<0.05). A significant difference did not exist in the level of forced expiratory volume in 1 s (FEV1), FEV1%pred, FEV1/forced vital capacity (FVC), inspiratory capacity (IC), residual volume (RV), total lung capacity (TLC) and RV/TLC (p>0.05). (2) Peak Load, Peak oxygen uptake (), Peak%pred, Peak, Peakpulse and the ratio ofincrease to WR increase () were significantly lower in the anaemia group (p<0.05); however, Peak minute ventilation (VE), Lowest/carbon dioxide output () and Peak dead space/tidal volume ratio (VD/VT) were similar between the 2 groups (p>0.05). (3) A strong positive correlation was found between Hb concentration and Peakin patients with anaemia (r=0.702, p<0.01).

Conclusions

Anaemia has a negative impact on gas exchange and exercise tolerance during exercise in patients with severe COPD. The decrease in amplitude of Hb levels is related to the quantity of oxygen uptake.
Clarifying the learning experiences of healthcare professionals with in situ and off-site simulation-based medical education: a qualitative study
Authors: Sørensen Jette Led , Navne Laura Emdal , Martin Helle Max , Ottesen Bent , Albrecthsen Charlotte Krebs , Pedersen Berit Woetmann , Kjærgaard Hanne , van der Vleuten Cees
Published: October 2015

Objective

To examine how the setting in in situ simulation (ISS) and off-site simulation (OSS) in simulation-based medical education affects the perceptions and learning experience of healthcare professionals.

Design

Qualitative study using focus groups and content analysis.

Participants

Twenty-five healthcare professionals (obstetricians, midwives, auxiliary nurses, anaesthesiologists, a nurse anaesthetist and operating theatre nurse) participated in four focus groups and were recruited due to their exposure to either ISS or OSS in multidisciplinary obstetric emergencies in a randomised trial.

Setting

Departments of obstetrics and anaesthesia, Rigshospitalet, Copenhagen, Denmark.

Results

Initially participants preferred ISS, but this changed after the training when the simulation site became of less importance. There was a strong preference for simulation in authentic roles. These perceptions were independent of the ISS or OSS setting. Several positive and negative factors in simulation were identified, but these had no relation to the simulation setting. Participants from ISS and OSS generated a better understanding of and collaboration with the various health professionals. They also provided individual and team reflections on learning. ISS participants described more experiences that would involve organisational changes than the OSS participants did.

Conclusions

Many psychological and sociological aspects related to the authenticity of the learning experience are important in simulation, but the physical setting of the simulation as an ISS and OSS is the least important. Based on these focus groups OSS can be used provided that all other authenticity elements are taken into consideration and respected. The only difference was that ISS had an organisational impact and ISS participants talked more about issues that would involve practical organisational changes. ISS and OSS participants did, however, go through similar individual and team learning experiences.
Longitudinal qualitative exploration of cancer information-seeking experiences across the disease trajectory: the INFO-SEEK protocol
Authors: Germeni Evi , Bianchi Monica , Valcarenghi Dario , Schulz Peter J
Published: October 2015

Introduction

Α substantial corpus of literature has sought to describe the information-seeking behaviour of patients with cancer. Yet, available evidence comes mainly from cross-sectional studies, which provide ‘snapshots’ of patients’ information needs and information-seeking styles at a single time point. Only a few longitudinal studies currently exist; however, these are quantitative in nature and, despite successfully documenting changes in patients’ information needs throughout the clinical course of cancer, they have failed to provide an evidence-based interpretation of the causes and consequences of change. The goal of this study is threefold: First, we wish to provide a holistic understanding of how cancer information-seeking behaviour may evolve across different stages of the patient journey. Second, we will seek to elucidate the contextual and intervening conditions that may affect possible changes in information seeking. Third, we will attempt to identify what the consequences of these changes are, while heightening their implications for clinical practice and policy.

Methods and analysis

We will carry out a longitudinal qualitative study, based on face-to-face, in-depth interviews with approximately 25 individuals diagnosed with cancer. Patients will be recruited from 2 oncology hospitals located in Ticino, Switzerland, and will be interviewed at 3 different time points: (1) within 2 weeks after receiving the cancer diagnosis; (2) within 2 weeks after their initial treatment; and (3) 6 months after their initial treatment. All interviews will be recorded and transcribed verbatim. A grounded theory approach will be used for the analysis of the data.

Ethics and dissemination

The study protocol has been approved by the Ethics Committee of Canton Ticino (CE 2813). Participation in the study will be voluntary, and confidentiality and anonymity ensured. Prior to study participation, patients will be asked to provide signed informed consent. Findings will be disseminated in international peer-reviewed journals and presented in relevant conferences.
The EARN-Health Trial: protocol for a randomised controlled trial to identify health effects of a financial savings programme among low-income US adults
Authors: Basu Sanjay , Hamad Rita , White Justin S , Modrek Sepideh , Rehkopf David H , Cullen Mark R
Published: October 2015

Introduction

A theory within the social epidemiology field is that financial stress related to having inadequate financial savings may contribute to psychological stress, poor mental health and poor health-related behaviours among low-income US adults. Our objective is to test whether an intervention that encourages financial savings among low-income US adults improves health behaviours and mental health.

Methods and analysis

A parallel group two-arm controlled superiority trial will be performed in which 700 participants will be randomised to the intervention or a wait list. The intervention arm will be provided an online Individual Development Account (IDA) for 6 months, during which participants receive a $5 incentive (£3.2, €4.5) for every month they save $20 in their account (£12.8, €18), and an additional $5 if they save $20 for two consecutive months. Both groups will be provided links to standard online financial counselling materials. Online surveys in months 0 (prior to randomisation), 6 and 12 (6 months postintervention) will assess self-reported health behaviours and mental health among participants in both arms. The surveys items were tested previously in the US Centers for Disease Control and Prevention national health interviews and related health studies, including self-reported overall health, health-related quality of life, alcohol and tobacco use, depression symptoms, financial stress, optimism and locus of control, and spending and savings behaviours. Trial data will be analysed on an intent-to-treat basis.

Ethics and dissemination

This protocol was approved by the Institutional Review Board of Stanford University (Protocol ID: 30641). The findings of the trial will be disseminated through peer-reviewed publication.

Trial registration number

IdentifierNCT02185612; Pre-results.
Secular trends and evaluation of complex interventions: the rising tide phenomenon
Authors: Chen Yen-Fu , Hemming Karla , Stevens Andrew J , Lilford Richard J
Published: October 2015

Evaluations of service delivery interventions with contemporaneous controls often yield null results, even when the intervention appeared promising in advance. There can be many reasons for null results. In this paper we introduce the concept of a ‘rising tide’ phenomenon being a possible explanation of null results. We note that evaluations of service delivery interventions often occur when awareness of the problems they intend to address is already heightened, and pressure to tackle them is mounting throughout a health system. An evaluation may therefore take place in a setting where the system as a whole is improving – where there is a pronounced temporal trend or a ‘rising tide causing all vessels to rise’. As a consequence, control sites in an intervention study will improve. This reduces the difference between intervention and control sites and predisposes the study to a null result, leading to the conclusion that the intervention has no effect. We discuss how a rising tide may be distinguished from other causes of improvement in both control and intervention groups, and give examples where the rising tide provides a convincing explanation of such a finding. We offer recommendations for interpretation of research findings where improvements in the intervention group are matched by improvements in the control group. Understanding the rising tide phenomenon is important for a more nuanced interpretation of null results arising in the context of system-wide improvement. Recognition that a rising tide may have predisposed to a null result in one health system cautions against generalising the result to another health system where strong secular trends are absent.
Pathogenesis-related genes as tools for discovering the response of onion defence system against Iris yellow spot virus infection
Authors: ElMorsi Adel , Abdelkhalek Ahmed , AlShehaby Omar , Hafez Elsayed E.
Published: October 2015

The Iris yellow spot virus (IYSV) is a viral pathogen of onions and causes severe damage and economic loss in affected onion crops. Pathogenesis-related (PR) genes are part of the innate immune response that onions harbour against viral diseases, which to date remains unclear. Using a sensitive and reliable real-time quantitative PCR method, the dynamic expression of five different genes in infected onions were investigated after biological inoculation with virulent isolate of Thrips tabaci (Lindeman). The transcription levels of PR1, PR2, PR3, PR4, and PR5 genes were highly expressed 1 day post inoculation (dpi). Furthermore, statistical analysis revealed a significant change in peak expression levels of PR1 after 8 dpi and PR3 after 9 dpi. In contrast, the expression level change for the other genes was only moderate. Further, we determined and ranked the expression stability of three reference genes (EF1-α, 18S rRNA, and β-actin) using geNorm and NormFinder. The overall analysis demonstrated that β-actin is the most informative gene, which can be utilised as an internal control for quantitative gene expression. Our study findings not only provide guidelines for selection of appropriate reference genes in virally infected onions, but also valuable information concerning immune response related genes associated with the initial plant defences against viral infection. Moreover, the PR1 gene appears to be a disease-specific gene related to the IYSV infection in onion tissues.
Fishes from the Lower Triassic portion of the Sulphur Mountain Formation in Alberta, Canada: geological context and taxonomic composition
Authors: Neuman Andrew G.
Published: October 2015

The Sulphur Mountain Formation in Alberta, Canada, comprises shales, siltstones, and limestones laid down on the continental shelf and shoreline along the western margin of the North American Craton during the Early and Middle Triassic. At least 13 taxa of fossil marine fishes have been found at a number of Triassic localities along the Front Ranges and foothills in Alberta. Common taxa (Boreosomus, Birgeria, Bobasatrania, Australosomus, Saurichthys, parasemionotids, and coelacanths) found at localities in Alberta are similar to those found at the classic Lower and Middle Triassic localities near Wapiti Lake, British Columbia, and in East Greenland, Spitzbergen, Madagascar, and China. The occurrence of Lower Triassic fishes in western Alberta shows that this fauna was widespread, occurring over at least 1000 km of shoreline, and that ecological and environmental factors were similar along the western edge of the Panthalassic Ocean during the Early Triassic.
Middle Cenomanian (Late Cretaceous) molluscs of the Shaftesbury Formation, Birch Mountains, northeastern Alberta, Canada
Authors: Bohach Lisa L. , Frampton Emily K.
Published: October 2015

Historical Resources Impact Assessment and Mitigation studies have documented a new middle Cenomanian invertebrate fauna from the Shaftesbury Formation in the Birch Mountains, northwest of Fort McMurray, in northeastern Alberta, Canada. Although older portions (Albian) of the Shaftesbury Formation in Alberta and British Columbia have yielded invertebrate fossils, this is the first fauna of middle Cenomanian age known for the unit. The fauna includes the ammonites Acanthoceras wyomingense and Borissjakoceras orbiculatum, the inoceramid bivalves Inoceramus dunveganensis and Inoceramus prefragilis stephensoni, and the gastropod Pirsila tensa. The occurrence of the late middle Cenomanian zonal fossil A. wyomingense allows correlation between the middle “Fish Scales Formation” of the Shaftesbury Formation and the lower part of the Labiche Formation of Alberta, and with five units farther to the south in the United States, namely the Greenhorn Limestone, Lincoln Formation, and Graneros Shale of Kansas, the Frontier Formation of Wyoming, and the Belle Fourche Shale of Montana.
Redescription of UALVP 40, an unusual specimen ofChasmosaurusLambe, 1914 (Ceratopsidae: Chasmosaurinae) bearing long postorbital horns, and its implications for ontogeny and alpha taxonomy of the genus
Authors: Konishi Takuya
Published: October 2015

UALVP 40, an articulated and reasonably complete skull of a small chasmosaurine dinosaur collected in 1920 by George F. Sternberg from the lower unit of the Dinosaur Park Formation, Dinosaur Provincial Park, Alberta, Canada, is here redescribed. The focus of the study is on the newly prepared right side of the skull and the hitherto undescribed mandible. There are substantial differences between the right and the left side of the skull, most notably the right postorbital horncore exhibits a greater angle of inclination at 60° from horizontal, which is approximately 15° greater than that of the left. The right side of the skull also shows many unfused cranial sutures that are obliterated on the left side. These unfused sutures and the short predentary lacking an anterior elongation, indicate that UALVP 40 likely represents a subadult individual. UALVP 40 is diagnosed to the genus Chasmosaurus by its possession of the following: (i) premaxillary flange along entire anterior margin of external naris; (ii) supraorbital horns curving posteriorly along their length; and (iii) squamosal dorsal border laterally adjacent to supratemporal fenestra straight in profile, sloping posteroventrally at a shallow angle before ascending farther posteriorly to form lateral border of parietal fenestra. The last character is newly proposed. A bivariate correlation in UALVP 40 and other Canadian specimens of Chasmosaurus bearing long postorbital horncores (>150 mm long) reveals a near isometric relationship between interorbital width and horn length. This may indicate those specimens represent an ontogenetic series of a single species diagnosed by long postorbital horncores.
Marine turtles from the Late Cretaceous of Alberta, Canada
Authors: Brinkman Donald B. , Densmore Michael , Rabi Márton , Ryan Michael J. , Evans David C.
Published: October 2015

Previously reported and new specimens of marine turtles from the late Campanian of Alberta, Canada, provide additional information on the diversity and distribution of chelonioid turtles at this time. An articulated carapace from the Bearpaw Formation previously interpreted as Lophochelys niobrarae is considered to be a juvenile of a specifically indeterminate chelonioid and is referred to Lophochelys sp. Isolated neurals and a hyoplastron from nonmarine estuarine deposits in the uppermost beds of the Dinosaur Park Formation are tentatively referred to Lophochelys sp. These specimens suggest that this chelonioid could enter freshwater environments. A new chelonioid, Kimurachelys slobodae gen. et sp. nov., is recognized on the basis of two mandibles and a maxilla from the uppermost beds of the Dinosaur Park Formation of southeastern Alberta. A partial postcranial skeleton of an indeterminate chelonioid from the Bearpaw Formation provides additional evidence that chelonioids of this formation included taxa that were phylogenetically intermediate between chelonioids of the late Santonian and members of the crown group.
International Barcode of Life: Evolution of a global research community
Authors: Adamowicz Sarah J.
Published: October 2015

The 6th International Barcode of Life Conference (Guelph, Canada, 18–21 August 2015), themed Barcodes to Biomes, showcases the latest developments in DNA barcoding research and its diverse applications. The meeting also provides a venue for a global research community to share ideas and to initiate collaborations. All plenary and contributed abstracts are being published as an open-access special issue of Genome. Here, I use a comparison with the 3rd Conference (Mexico City, 2009) to highlight 10 recent and emerging trends that are apparent among the contributed abstracts. One of the outstanding trends is the rising proportion of abstracts that focus upon multiple socio-economically important applications of DNA barcoding, including studies of agricultural pests, quarantine and invasive species, wildlife forensics, disease vectors, biomonitoring of ecosystem health, and marketplace surveys evaluating the authenticity of seafood products and medicinal plants. Other key movements include the use of barcoding and metabarcoding approaches for dietary analyses—and for studies of food webs spanning three or more trophic levels—as well as the spread of next-generation sequencing methods in multiple contexts. In combination with the rising taxonomic and geographic scope of many barcoding iniatives, these developments suggest that several important questions in biology are becoming tractable. “What is this specimen on an agricultural shipment?”, “Who eats whom in this whole food web?”, and even “How many species are there?” are questions that may be answered in time periods ranging from a few years to one or a few decades. The next phases of DNA barcoding may expand yet further into prediction of community shifts with climate change and improved management of biological resources.