bluuebunny/crossref_metadata_2025 huggingface dataset:
Order Matters: The Benefits of Ordinal Fragility Curves for Damage and Loss Estimation
Authors: Nguyen Michele , Lallemant David
Published: August 2021

Probabilistic loss assessments from natural hazards require the quantification of structural vulnerability. Building damage data can be used to estimate fragility curves to obtain realistic descriptions of the relationship between a hazard intensity measure and the probability of exceeding certain damage grades. Fragility curves based on the lognormal cumulative distribution function are popular because of their empirical performance as well as theoretical properties. When we are interested in estimating exceedance probabilities for multiple damage grades, these are usually derived per damage grade via separate probit regressions. However, they can also be obtained simultaneously through an ordinal model which treats the damage grades as ordered and related instead of nominal and distinct. When we use nominal models, a collapse fragility curve is constructed by treating data of “near‐collapse” and “no damage” the same: as data of noncollapse. This leads to a loss of information. Using synthetic data as well as real‐life data from the 2015 Nepal earthquake, we provide one of the first formal demonstrations of multiple advantages of the ordinal model over the nominal approach. We show that modeling the ordering of damage grades explicitly through an ordinal model leads to higher sensitivity to the data, parsimony and a lower risk of overfitting, noncrossing fragility curves, and lower associated uncertainty.
Approximate Laplace Approximations for Scalable Model Selection
Authors: Rossell David , Abril Oriol , Bhattacharya Anirban
Published: August 2021

We propose the approximate Laplace approximation (ALA) to evaluate integrated likelihoods, a bottleneck in Bayesian model selection. The Laplace approximation (LA) is a popular tool that speeds up such computation and equips strong model selection properties. However, when the sample size is large or one considers many models the cost of the required optimizations becomes impractical. ALA reduces the cost to that of solving a least-squares problem for each model. Further, it enables efficient computation across models such as sharing pre-computed sufficient statistics and certain operations in matrix decompositions. We prove that in generalized (possibly non-linear) models ALA achieves a strong form of model selection consistency for a suitably-defined optimal model, at the same functional rates as exact computation. We consider fixed- and high-dimensional problems, group and hierarchical constraints, and the possibility that all models are misspecified. We also obtain ALA rates for Gaussian regression under non-local priors, an important example where the LA can be costly and does not consistently estimate the integrated likelihood. Our examples include non-linear regression, logistic, Poisson and survival models. We implement the methodology in the R package mombf.
Does it matter who extorts? Extortion by competent and incompetent enforcers*
Authors: Samuel Andrew , Mishra Ajit
Published: August 2021

This paper offers a novel explanation for extortion, which is the practice of demanding payments from compliant agents by law‐enforcement officers. Namely, that extortion occurs due to the officer's incompetence, where the competence level is endogenous. Because competence improves enforcement, extortion affects deterrence directly by weakening agents' incentive to be compliant and indirectly by affecting officers' incentives to become competent. Accordingly, the harmful effects of extortion on deterrence depend on whether the competent or incompetent officer extorts. We show that extortion by incompetent officers is the lesser of the two evils, compared to bribery.
Development of a video analysis protocol and assessment of fall characteristics in equestrian cross‐country eventing
Authors: Nylund Lindsay E. , Sinclair Peter J. , McLean Andrew N. , Cobley Stephen
Published: August 2021

Cross‐country eventing is one of the highest‐risk sporting activities for serious injury outcomes. This study investigated relationships between fall characteristics and high‐risk falls at jumps in cross‐country eventing. A video analysis protocol was systematically developed to analyze 87 video recordings of high‐risk rider falls; defined as when the rider's head impacted the ground and/or where there was potential horse impact with the rider. Falls were classified according to competition type, jump type, horse‐related, and rider‐related factors. At least one high‐risk fall characteristic was observed in 45 of 87 examined falls. Multivariable best subsets regression identified five independent variables explaining 38.4% of the variance in the number of high‐risk falls. Increased likelihood of high‐risk falls was associated with continuation of horse direction or speed upon rider ground impact, higher jump approach speed, changes in rider body posture upon landing, rider air jacket usage, and reduced rider fall time. The Eventing Fall Assessment Instrument (EFAI) video analysis protocol (attached as supplementary material) facilitated systematic examination of multiple characteristics associated with high‐risk falls and identified likely influential characteristics. Based on EFAI and subsequent data analyses, findings suggest optimized approach speed for correct striding and take‐off; jump design to enable run‐out; and rider training could help reduce the occurrence of high‐risk falls. Air jacket usage and their design characteristics warrant further investigation.
Clinical Teacher Training for health professionals: From blended to online and (maybe) back again?
Authors: Burgess Annette , Bansal Akhil , Clarke Antonia , Ayton Tom , van Diggele Christie , Clark Tyler , Matar Elie
Published: August 2021

Background

The Clinical Teacher Training (CTT) programme was originally developed as an interprofessional, blended learning programme, to support health professionals working across health services within Australia, although it has also been delivered internationally. With the disruption of COVID‐19, we rapidly moved to ‘online only’ delivery. We sought to modify the programme, ensuring that the constructivist paradigms important for our learner experience through the original blended format were maintained in the online platform.

Approach

Consisting of 10 modules on a range of topics, the new CTT online only programme was facilitated online across 6 weeks with asynchronous and synchronous assessable activities, and provision of peer and facilitator feedback. The learning outcomes for each module were similar to the ‘blended learning’ format. The new programme was delivered three times throughout 2020 and completed by a total of 208 health professionals from across 10 metropolitan and rural health districts.

Evaluation

The focus of our evaluation was on the programme's final 2020 iteration, for which we had ethics approval. Participants (n = 59) were from diverse health professions, across five metropolitan and rural health districts. We prioritised the learner experience in constructing our evaluation strategy. Quantitative and qualitative data were collected by post‐course questionnaire and analysed using descriptive statistics and thematic analysis. Twenty participants (34%) responded to the post‐course questionnaire. Participants valued the structure, topics, clear outcomes, timeframe, online resources, small group activities, feedback and the flexibility and accessibility afforded by online only delivery. However, participants identified a need for additional ‘real‐time’ engagement in activities. Faculty were surprised by the time required to adequately facilitate online learning, and similarly, valued the real‐time interactions.

Implications

The online only CTT programme provided an excellent, scalable framework to ensure continued provision of a relevant and accessible training resource for clinicians working in metropolitan and regional/rural health services. Learner‐reported achievement of programme learning outcomes was not negatively impacted by online only delivery. Balancing these resource advantages with learner preferences and our desire to build active teaching networks, we will continue to host the majority of the programme online, while offering short face‐to‐face sessions within local contexts.
PENCIRIAN TEMPORAL SKALA KECIL AIR SISA DOMESTIK PERBANDARAN
Authors: Hanafiah Z. M. , Mohtar W. H. M. W. , Bachi' N. A. , Abdullah N. A. , Abdullah M. Z. , Manan T. S. A. , Amir A.
Published: August 2021

Sewage treatment plants (STP) in Malaysia are designed to treat a load of contaminants according to the level of concentration for chemical oxygen demand (COD) and nitrogen ammonia (NH3-N) of 250 mg/L and 30 mg/L, respectively. However, studies show that the organic load of Malaysian wastewater is low and even temporarily fluctuates resulting in the low effectiveness of treatment especially in ammonia removal and consequently cause effluents that do not undergo proper treatment to be released into the environment. Therefore, this study aims to identify concentrations of COD and NH3-N in the influent of urban domestic wastewater along with other physico-chemical characteristics. Two locations of the STP were chosen based on the urban area with different catchment sizes for a population equivalent (PE) 60,000 for the first STP (LRK#1), and 150,000 for the second STP (LRK#2). These parameters include pH, temperature, conductivity, turbidity, total suspended solids (TSS), nitrogen nitrate (NO3-N), total Kjeldahl nitrogen (TKN) as well as heavy metals such as Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn). The sampling and analysis methods used the guidelines recommended in the American Public Health Association (APHA). The results give the highest average COD concentrations for the LRK#1 and LRK#2 are 180.5 mg/L and 380.9 mg/L, respectively. The highest NH3-N concentrations were 33.53 mg/L for LRK#1 and 31.63 mg/L for LRK#2. Overall, the wastewater physico-chemical characteristics of both treatment plants show wastewater in the medium and low concentration categories.
PHYSICAL PROPERTIES OF NOVEL α-Fe2O3/NiO HETEROSTRUCTURES THROUGH IMMERSION/ SOL–GEL SPIN COATING METHOD: DIFFERENT DEPOSITION NUMBERS OF NiO LAYER
Authors: Parimon N. , Mamat M. H. , Suriani A. B. , Mohamed A. , Ahmad M. K. , Banu I. B. Shameem , Vasimalai N. , Rusop M.
Published: August 2021

The novel hematite (α-Fe2O3)/nickel oxide (NiO) heterostructures were grown on fluorine-doped tin oxide (FTO) coated glass substrates at various deposited NiO of 3, 5, and 7 layers. The heterostructures were successfully synthesized using the immersion and sol–gel spin coating methods for α-Fe2O3 and NiO films, respectively. The field emission scanning electron microscopy analysis showed that each sample of α-Fe2O3/NiO heterostructures has a unique surface morphology when deposited with different NiO layers. The X-ray diffraction pattern shows that the number of NiO layers affected the diffraction peaks. The NiO diffraction peak intensity at (111) plane increased when the deposition number of NiO layer was increased. The crystallite sizes of NiO were 35.4, 33.6, and 38.0 nm for 3-, 5-, and 7-layer NiO, respectively. The interplanar spacing, lattice parameter, and unit cell volume indicate NiO with 3-layer as the highest, while 5- and 7-layer had the same values. Meanwhile, the strain and stress values show the compressive strain and tensile stress, respectively. The optical properties reveal that the highest transmittance and the lowest absorbance percentages were recorded for a 3-layer NiO sample. In contrast, the lowest transmittance and the highest absorbance percentages were obtained for the sample with 5-layer NiO. Different thicknesses and morphologies of heterostructures explained these situations. In addition, each unique heterostructure of α-Fe2O3/NiO with high visible light absorption nature is perceived to reduce the bandgap energy and has the potential to be used in sensor and solar cell applications.
MOTION CHARACTERIZATION OF A SWITCHED RELUCTANCE ACTUATOR – A SIGNAL DRIVEN APPROACH
Authors: Md Ghazaly Mariam , Yusri Izzati , Lagani Muhammad Shadiq
Published: August 2021

In this paper, the researchers have described the development, design and characterization of a Switched Reluctance (SR) actuator, with a rotary motion, having a single-excitation activity. This SR actuator design consisted of a stator and rotor core and was based on the simplest SR actuator model design, with a Stator-to-Rotor pole ratio (S: R) of 6:4. In this design, the winding was coiled at Phase A, which enabled the single step motion characterization based on a single excitation. This SR actuator prototype showed a compact size, with a 36 mm stack length and a 60 mm outer diameter. This feature allowed small machine applications like the precision robotic machining, but required a low production cost, as it lacked a permanent magnet. On the other hand, the SR actuator consisted of highly non-linear characteristics and showed uncontrolled motion behavior. While achieving a very precise motion, it is important to suppress the non-linear characteristics of an actuator. Hence, the researchers designed the linearizer unit based on its characterization at Position 0°, which was related to the excitation current and the rotary angles for the various initial rotor positions. This initial position was chosen as it reflected the characteristics which indicated the self-starting characteristics. Thereafter, the researchers experimentally investigated the appropriate driving signal for this SR actuator as the normal step input signal showed a lower precision motion because of the discharging effect-related issues.
EFFECT OF STOCKING DENSITY ON THE GROWTH PERFORMANCE OF RED TILAPIA IN ZEOLITE SUPPLEMENTED CLOSED SYSTEM
Authors: Hong Ku Boon , Jani Musfiroh , Meor Mohamad Zain Rabiatul Adawiyah , Mohd Fauzi Norashikin
Published: August 2021

Food demand is expected to surge due to the increase of world population. Malaysia is one of the top fish consumption countries in Asia, but the reduction of capture fishery has led to the increase for aquaculture for tilapia to overcome the demand. Thus, the objective of this study was to compare the growth performance of red tilapia at different stocking densities of zeolite supplemented closed system. Red tilapia fry was stocked into aquarium. Five treatments (containing zeolite and without zeolite) with two replicates were used. Food was given twice a day with 2% of total biomass of the fish. Weight and length of red tilapia were measured every two weeks. The zeolite treatments which recorded the highest final mean weight was T1 with the lowest stocking density (5 fish) while in T5 (highest stocking density), lowest mean weight was recorded. Specific growth rate and length gain in T1 was significantly higher than other treatments. On the other hand, there was no significant difference in growth parameters between the treatments with and without zeolite. The results revealed that red tilapia stocked in the T1 of the lowest stocking density (5 fish) had the highest growth performance than the fish in other treatments. Compared to other treatments, T1 recorded the highest final length and weight, weight and length gain, Specific Growth Rate % (SGR) among the treatments. The findings will be useful for the practitioners to understand the best practice for stocking density in zeolite supplemented closed system.
A Pragmatic Approach for the Evaluation of Depth-Sensing Indentation in the Self-Similar Regime
Authors: Mahdavi Hamidreza , Poulios Konstantinos , Niordson Christian F.
Published: August 2021

This work evaluates and revisits elements from the depth-sensing indentation literature by means of carefully chosen practical indentation cases, simulated numerically and compared to experiments. The aim is not to provide a comprehensive study, but to close a series of debated subjects, which constitute major sources of inaccuracies in the evaluation of depth-sensing indentation data in practice, with the help of illustrative examples. First, own examples and references from the literature are presented in order to demonstrate how crucial self-similarity detection and blunting distance compensation are, for establishing a rigorous link between experiments and simple sharp indenter models. Moreover, it is demonstrated, once again, in terms of clear and practical examples, that no more than two parameters are necessary to achieve an excellent match between a sharp indenter finite element simulation and experimental force–displacement data. The clear conclusion is that reverse analysis methods promising to deliver a set of three unique material parameters from depth-sensing indentation cannot be reliable. Lastly, in light of the broad availability of modern finite element software, we also suggest to avoid the rigid indenter approximation, as it is shown to lead to unnecessary inaccuracies. All conclusions from the critical literature review performed lead to a new semi-analytical reverse analysis method, based on available dimensionless functions from the literature and a calibration against case specific finite element simulations. Implementations of the finite element model employed are released as supplementary material, for two major finite element software packages.
Anisotropic Mechanics of Vascular Smooth Muscle Cells Exposed to Dynamic Loads
Authors: Rothermel Taylor , Franczek Ian , Alford Patrick
Published: August 2021

Vascular smooth muscle cells (VSMCs) are the most prevalent cells in the arterial wall. In vivo, arteries are exposed to dynamic biaxial loads, thus when characterizing VSMC mechanics it is important to determine their anisotropic and time-dependent mechanical properties. Here, we use cellular microbiaxial stretching (CµBS) to apply complex deformations to single micropatterned VSMCs and measure the resulting changes in cell stress. Previously, CµBS has been used to measure VSMC mechanical properties in response to extensional strain. Here, we measure changes in cell stress in response to both extension and compression. Additionally, we measure immediate temporal changes in stress in response to cyclically applied deformations. We find that the VSMCs display clear hysteresis when incrementally stretched and compressed and demonstrate cycle-dependent stress-relaxation when exposed to cyclic step change extension and compression. Finally, we demonstrate that a Hill-type active fiber model is capable of replicating all observed hysteresis and cycle-dependent stress-relaxation, suggesting that the temporal stress-strain behavior of the cell is regulated by acto-myosin contraction and relaxation, rather than passive viscoelasticity. This study improves upon previous studies of cellular mechanical properties by considering cellular architecture and more complex deformations when measuring the time-dependent mechanical properties of VSMCs. These findings have important implications for modeling in mechanobiology as VSMCs are mechanosensitive and actively respond to changes in their mechanical environment to maintain vascular function.
Inversion-Based Hysteresis Compensation Using Adaptive Conditional Servocompensator for Nanopositioning Systems
Authors: Al-Nadawi Yasir K. , Tan Xiaobo , Khalil Hassan K.
Published: August 2021

Nanopositioning stages are widely used in high-precision positioning applications. However, they suffer from an intrinsic hysteretic behavior, which deteriorates their tracking performance. This study proposes an adaptive conditional servocompensator (ACS) to compensate the effect of the hysteresis when tracking periodic references. The nanopositioning system is modeled as a linear system cascaded with hysteresis at the input side. The hysteresis is modeled with a modified Prandtl–Ishlinskii (MPI) operator. With an approximate inverse MPI operator placed before the system hysteresis operator, the resulting system takes a semi-affine form. The design of the ACS consists of two stages: first, we design a continuously implemented sliding mode control (SMC) law. The hysteresis inversion error is treated as a matched disturbance, and an analytical bound on the inversion error is used to minimize the conservativeness of the SMC design. The second part of the controller is the ACS. Under mild assumptions, we establish the well-posedness and periodic stability of the closed-loop system. In particular, the solution of the closed-loop error system will converge exponentially to a unique periodic solution in the neighborhood of zero. The efficacy of the proposed controller is verified experimentally on a commercial nanopositioning device under different types of periodic reference inputs, via comparison with multiple inversion-based and inversion-free approaches.
Electromigration Analysis of Solder Joints for Power Modules Using an Electrical-Thermal-Stress Coupled Model
Authors: Kato Mitsuaki , Omori Takahiro , Goryu Akihiro , Fumikura Tomoya , Hirohata Kenji
Published: August 2021

Power modules are being developed to increase power output. The larger current densities accompanying increased power output are expected to degrade solder joints in power modules by electromigration. In previous research, numerical analysis of solder for electromigration has mainly examined ball grid arrays in flip-chip packages in which many solder balls are bonded under the semiconductor device. However, in a power module, a single solder joint is uniformly bonded under the power device. Because of this difference in geometric shape, the effect of electromigration in the solder of power modules may be significantly different from that in the solder of flip chips packages. This report describes an electromigration analysis of solder joints for power modules using an electrical-thermal-stress coupled analysis. First, we validate our numerical implementation and show that it can reproduce the vacancy concentrations and hydrostatic stress almost the same as the analytical solutions. We then simulate a single solder joint to evaluate electromigration in a solder joint in a power module. Once inelastic strain appears, the rate of increase in vacancy concentration slows, while the inelastic strain continuously increases. This phenomenon demonstrates that elastic-plastic-creep analysis is crucial for electromigration analysis of solder joints in power modules. Next, the solder joint with a power device and a substrate as used in power modules was simulated. Plasticity-creep and longitudinal gradient generated by current crowding have a strong effect on significantly reducing the vacancy concentration at the anode edge over a long period of time.
Coupled Time and Passage Spectral Method for an Efficient Resolution of Turbomachinery Far Upstream Wakes
Authors: Wang Dingxi , Zhang Sen , Huang Xiuquan , Huang Huang
Published: August 2021

The paper proposes a novel numerical method called coupled time and passage spectral method for an efficient resolution of far upstream wakes in an unsteady analysis of flow field within generic multiple blade rows. The proposed method is a very simple and natural extension of the time spectral form harmonic balance method. By including inter blade phase angle and passage index in a truncated Fourier series, the proposed method is capable of circumventing the limitations of the harmonic balance method in dealing with zero frequency harmonics and time harmonics with same frequency but different inter blade phase angles. Different from the harmonic balance method, which seeks solution at different time instants of the same passage, the coupled spectral method seeks solutions at different passages and time instants. Same as the harmonic balance method, all these solutions are connected via a spectral operator. Coupled time and passage sampling is performed using the modified Gram Schmidt process to choose the time and passage pairs which give the most orthogonal rows of an inverse Fourier transform matrix. The coupled time and passage spectral method requires minimal change to an existing harmonic balance solver. A numerical case study has been provided in the paper to demonstrate the expected capability against the harmonic balance method.
A Combined Volume of Fluid and Immersed Boundary Method for Modeling of Two-Phase Flows With High Density Ratio
Authors: Jin Qiu , Hudson Dominic , Price W. Geraint
Published: August 2021

A combined volume of fluid and immersed boundary method is developed to simulate two-phase flows with high density ratio. The problems of discontinuity of density and momentum flux are known to be challenging in simulations. In order to overcome the numerical instabilities, an extra velocity field is designed to extend velocity of the heavier phase into the lighter phase and to enforce a new boundary condition near the interface, which is similar to nonslip boundary conditions in fluid–structure interaction problems. The interface is captured using a volume of fluid method, and a new boundary layer is built on the lighter phase side by an immersed boundary method. The designed boundary layer helps to reduce the spurious velocity caused by the imbalance of dynamic pressure gradient and density gradient and to prevent tearing of the interface due to the tangential velocity across the interface. The influence of time-step, density ratio, and spatial resolution is studied in detail for two set of cases, steady stratified flow and convection of a high-density droplet, where direct comparison is possible to potential flow analysis (i.e., infinite Reynold s number). An initial study for a droplet splashing on a thin liquid film demonstrates applicability of the new solver to real-life applications. However, detailed comparisons should be performed in the future for finite Reynold s number cases to fully demonstrate the improvements in accuracy and stability of high-density ratio two-phase flow simulations offered by the new method.
Condition Setting in Sport: A Case Study Approach to Explore Program Planning by Canadian University Coaches
Authors: Staehli Julie-Anne , Martin Luc J. , Côté Jean
Published: August 2021

Based on a condition-setting approach derived from organizational psychology, the authors investigated the conditions that university sport coaches considered and implemented prior to a competitive season. Using a collective case study approach, semistructured interviews were conducted at two time points, with five head coaches across different sports. Student-athletes from each team (n = 5) and the high performance director from the institution were also interviewed. The data were analyzed thematically to highlight the relevant conditions for coaches and their individual athletes and were then generalized across teams within the institution. The authors’ results support the utility of the condition-setting approach outlined by Hackman for sport. Specifically, coaches emphasized the need to (a) create a team vision with clear objectives, (b) opt for athletes of best fit, (c) assign team roles and expectations, (d) confirm and allocate necessary resources, and (e) have competent and prepared team coaching. Despite the generalizability of these themes, the authors’ results highlight the need to consider the context, as both the university environment generally and each specific program were bound by unique constraints (e.g., funding). Herein, the authors discuss their findings in relation to the broader literature, propose future directions, and provide practical implications for sport coaches and institutions.
Feasibility and Effectiveness of a Biography-Based Physical Activity Intervention in Institutionalized People With Dementia: Quantitative and Qualitative Results From a Randomized Controlled Trial
Authors: Gebhard Doris , Mess Filip
Published: August 2021

The objective of this multicenter randomized controlled trial was to evaluate the feasibility and effectiveness of a physical activity intervention for institutionalized people with dementia, individualized by capacity and biography. The intervention group (n = 34; age: mean = 86.09 years; 79.40% female; mean Mini-Mental State Examination value = 18.59) participated in a multicomponent training program, which included daily activities, dancing, gardening, and sports/games, twice weekly for 3 months. The control group (n = 29; age: mean = 86.34 years; 75.90% female; mean Mini-Mental State Examination value = 19.90) received standard care. Feasibility was evaluated by means of focus groups and feedback questionnaires. Functional performance (Short Physical Performance Battery and Timed Up and Go Test), activities of daily living, and gait were outcomes for effectiveness. A high adherence rate (80.46%) and uniformly positive feedback indicate that the piloted training program is feasible. The results show preliminary effectiveness on functional performance (Short Physical Performance Battery mean t0 = 3.15; mean t1 = 4.50; p = .006) and gait (e.g., velocity mean t0 = 46.97; mean t1 = 58.04; p = .007).
Preliminary Evidence for a Relationship Between Anxiety, Anger, and Impulsivity in Collegiate Athletes With Sport-Related Concussion
Authors: Byrd Megan M. , Kontos Anthony P. , Eagle Shawn R. , Zizzi Samuel
Published: August 2021

This study used an exploratory mixed-method sequential design to examine anger, impulsivity, and anxiety following sport-related concussions (SRC). Ten college athletes (M = 20.10 years, SD = 2.92) completed four measures 1–10 days postconcussion (Visit 1) and 11–20 days postconcussion (Visit 2). At return to play or 30 days postconcussion, the athletes completed a semistructured interview (follow-up) to assess their lived experiences of the emotional sequelae of concussions. All participants indicated experiencing some level of anxiety at Visit 1, with half the participants scoring above the measure’s threshold for probable clinical diagnosis of anxiety. The results found a significant decrease in symptoms and anxiety at Visit 2. Inductive coding revealed frustration, irritability, impulsive behavior, and fear of the unknown as themes pertaining to athletes’ experiences. The findings highlight the need for sports medicine and sport psychology professionals to provide athletes with information to normalize their emotional responses during recovery.
Evaluation of Susceptibility Testing Methods for Aztreonam and Ceftazidime-Avibactam Combination Therapy on Extensively Drug-Resistant Gram-Negative Organisms
Authors: Khan Ayesha , Erickson Samuel G. , Pettaway Cedric , Arias Cesar A. , Miller William R. , Bhatti Micah M.
Published: August 2021

Carbapenem-resistant
Enterobacterales
(CRE) and
Pseudomonas aeruginosa
(CR-PA) producing metallo-β-lactamases (MBLs) cause severe nosocomial infections with no defined treatment. The combination of aztreonam (ATM) with ceftazidime-avibactam (CZA) is a potential therapeutic option, but there is no approved, feasible testing method for use in clinical laboratories to assess the activity of two antimicrobials in combination.
Evaluation of AT-752, a Double Prodrug of a Guanosine Nucleotide Analog with
In Vitro
and
In Vivo
Activity against Dengue and Other Flaviviruses
Authors: Good Steven S. , Shannon Ashleigh , Lin Kai , Moussa Adel , Julander Justin G. , La Colla Paolo , Collu Gabriella , Canard Bruno , Sommadossi Jean-Pierre
Published: August 2021

Every year, millions of people worldwide are infected with dengue virus (DENV), with a significant number developing severe life-threatening disease. There are currently no broadly indicated vaccines or therapeutics available for treatment of DENV infection.
The Reaction of Innate Lymphoid Cells in the Mouse Female Genital Tract to Chlamydial Infection
Authors: Barth Svenja , Kirschnek Susanne , Ortmann Noemi , Tanriver Yakup , Häcker Georg
Published: August 2021

Innate lymphoid cells (ILCs) comprise five distinct subsets. ILCs are found at mucosal barriers and may fight invading pathogens.
Chlamydia
is an intracellular bacterium that infects the mucosa of the genital tract and can cause severe tissue damage.
Clostridioides difficile SpoVAD and SpoVAE Interact and Are Required for Dipicolinic Acid Uptake into Spores
Authors: Baloh Marko , Sorg Joseph A.
Published: August 2021

C. difficile
spore heat resistance provides an avenue for it to survive the disinfection protocols in hospital and community settings. The spore heat resistance is mainly the consequence of the high DPA content within the spore core.
Supplemental Material: Concurrent MORB-type and ultrapotassic volcanism in an extensional basin along the Laurentian Iapetus margin: Tectonomagmatic response to Ordovician arc-continent collision and subduction polarity flip
Authors: Gasser Deta , al. et
Published: August 2021

Supplemental Material containing a detailed description of analytical methods, additional geochemical and geochronological plots, as well as complete geochemical and geochronological data sets.
Vector of Trophic Resource Partitioning in the Variability of Individuals of the Generalized form of the Large African Barbs of the Barbus (= Labeobarbus) Intermedius Complex, Ethiopia, Tana, Langano and Awasa Lakes
Authors: Mironovsky A. N.
Published: August 2021

Analysis of the diversification of barbs of the generalized form of the Barbus (= Labeobarbus) intermedius complex in the monomorphic populations of Langano and Awasa lakes and in the polymorphic population of Lake Tana makes it possible to reveal parameters of the variability that is directed to trophic resource partitioning. The great similarity of the parameters revealed in the three studied water bodies shows that in monomorphic populations the structure of variability directed to trophic resource partitioning is identical to that in the polymorphic population. The concept of “vector of trophic resource partitioning” is introduced. In the polymorphic population, this vector makes the main contribution to the diversification of individuals, while its importance is secondary in monomorphic populations. It is concluded that the different evolutionary potential of polymorphic and monomorphic populations is determined by the specific weight of diversification caused by the vector of trophic resource partitioning. The original method of data analysis used in the study may be promising for studying similar situations in other systematic groups.
Smell loss as initial symptom of olfactory groove meningioma
Authors: Prem Bernhard , Mueller Christian Albert
Published: August 2021

Approximately 20% of the general population suffer from olfactory dysfunction (OD). Until today, olfactory function (OF) receives less attention than other human senses despite its significance for quality of life. The main causes of OD are upper respiratory tract infections, traumatic brain injuries and sinonasal diseases. Here, we report the case of a 28-year-old woman, who started to suffer from OD during pregnancy. Smell loss was attributed to pregnancy-induced rhinitis and initiated no further examinations. Nevertheless, OD persisted post partum and undulating headache occurred 1 year later. Only after visual impairment and one more year passing by, diagnosis of olfactory groove meningioma was made using MRI. With this case report, we want to highlight the importance of the symptom of smell loss. Patients reporting OD should undergo thorough anamnesis, endoscopy of the nasal cavity, psychophysical smell testing and radiographic imaging in unclear cases to determine diagnosis.
IgG4-related hepatic inflammatory pseudotumour: could MRI suggest the correct diagnosis?
Authors: Primitivo Ana , Oliveira Maria Helena , Gonçalves Afonso
Published: August 2021

We report a case of a 62-year-old woman, HIV positive, with a 3-week history of jaundice and elevated cholestatic enzymes. Imaging studies displayed intrahepatic biliary dilatation and a central liver lesion. Pathology described lesions of active cholangitis, lymphoplasmacytic infiltration and fibrosis, suggesting a hepatic inflammatory pseudotumour (IPT) IgG4 related. IgG4-related lymphoplasmacytic form of IPT belongs to IgG4-related diseases. We discuss the importance to include IgG4-related hepatic IPT as part of the differential diagnosis of any liver lesion, highlighting potential imaging clues that may help in establishing the correct diagnosis.
Meaningful and deep community engagement efforts for pragmatic research and beyond: engaging with an immigrant/racialised community on equitable access to care
Authors: Turin Tanvir Chowdhury , Chowdhury Nashit , Haque Sarika , Rumana Nahid , Rahman Nafiza , Lasker Mohammad A A
Published: August 2021

Primary healthcare access is one of the crucial factors that ensures the health and well-being of a population. Immigrant/racialised communities encounter a myriad of barriers to accessing primary healthcare. As global migration continues to grow, the development and practice of effective strategies for research and policy regarding primary care access are warranted. Many studies have attempted to identify the barriers to primary care access and recommend solutions. However, top-down approaches where the researchers and policy-makers ‘prescribe’ solutions are more common than community-engaged approaches where community members and researchers work hand-in-hand in community-engaged research to identify the problems, codevelop solutions and recommend policy changes. In this article, we reflect on a comprehensive community-engaged research approach that we undertook to identify the barriers to equitable primary care access among a South Asian (Bangladeshi) immigrant community in Canada. This article summarised the experience of our programme of research and describes our understanding of community-engaged research among an immigrant/racialised community that meaningfully interacts with the community. In employing the principles of community-based participatory research, integrated knowledge translation and human centred design, we reflect on the comprehensive community-engaged research approach we undertook. We believe that our reflections can be useful to academics while conducting community-engaged research on relevant issues across other immigrant/racialised communities.
Development and validation of a risk-adjustment model for mortality and hospital length of stay for trauma patients: a prospective registry-based study in Australia
Authors: Earnest Arul , Palmer Cameron , O'Reilly Gerard , Burrell Maxine , McKie Emily , Rao Sudhakar , Curtis Kate , Cameron Peter
Published: August 2021

Objectives

Adequate risk adjustment for factors beyond the control of the healthcare system contributes to the process of transparent and equitable benchmarking of trauma outcomes. Current risk adjustment models are not optimal in terms of the number and nature of predictor variables included in the model and the treatment of missing data. We propose a statistically robust and parsimonious risk adjustment model for the purpose of benchmarking.

Setting

This study analysed data from the multicentre Australia New Zealand Trauma Registry from 1 July 2016 to 30 June 2018 consisting of 31 trauma centres.

Outcome measures

The primary endpoints were inpatient mortality and length of hospital stay. Firth logistic regression and robust linear regression models were used to study the endpoints, respectively. Restricted cubic splines were used to model non-linear relationships with age. Model validation was performed on a subset of the dataset.

Results

Of the 9509 patients in the model development cohort, 72% were male and approximately half (51%) aged over 50 years . For mortality, cubic splines in age, injury cause, arrival Glasgow Coma Scale motor score, highest and second-highest Abbreviated Injury Scale scores and shock index were significant predictors. The model performed well in the validation sample with an area under the curve of 0.93. For length of stay, the identified predictor variables were similar. Compared with low falls, motor vehicle occupants stayed on average 2.6 days longer (95% CI: 2.0 to 3.1), p<0.001. Sensitivity analyses did not demonstrate any marked differences in the performance of the models.

Conclusion

Our risk adjustment model of six variables is efficient and can be reliably collected from registries to enhance the process of benchmarking.
“If we can show that we are helping adolescents to understand themselves, their feelings and their needs, then we are doing [a] valuable job”: counselling young people on sexual health in the Brook Advisory Centre (1965–1985)
Authors: Rusterholz Caroline
Published: August 2021

First opened in 1964 in London, the Brook Advisory Centres (BAC) were the first centres to provide contraceptive advice and sexual counselling to unmarried people in postwar Britain. Drawing on archival materials, medical articles published by BAC members and oral history interviews with former counsellors, this paper looks at tensions present in sexual health counselling work between progressive views on young people’s sexuality and moral conservatism. In so doing, this paper makes two inter-related arguments. First, I argue that BAC doctors, counsellors and social workers simultaneously tried to adopt a non-judgmental listening approach to young people’s sexual needs and encouraged a model of heteronormative sexual behaviours that was class-based and racialised. Second, I argue that emotional labour was central in BAC staff’s attempt to navigate and smooth these tensions. This emotional labour and the tensions within it is best illustrated by BAC’s pyschosexual counselling services, which on the one hand tried to encourage youth sexual pleasure and on the other taught distinctive gendered sexual roles that contributed to pathologising teenage sexual behaviours and desire.

In all, I contend that, in resorting to an emotionally orientated counselling, BAC members reconfigured for the young the new form of sexual subjectivity that had been in the making since the interwar years, that is, the fact that individuals regarded themselves as sexual beings and expressed feelings and anxieties about sex. BAC’s counselling work was as much a rupture with the interwar contraceptive counselling tradition—since it operated in a new climate, stressed a non-judgmental listening approach and catered for the young—as it was a continuity of some of the values of the earlier movement.
Development of a machine learning-based real-time location system to streamline acute endovascular intervention in acute stroke: a proof-of-concept study
Authors: Lim Dee Zhen , Yeo Melissa , Dahan Ariel , Tahayori Bahman , Kok Hong Kuan , Abbasi-Rad Mohammad , Maingard Julian , Kutaiba Numan , Russell Jeremy , Thijs Vincent , Jhamb Ashu , Chandra Ronil V , Brooks Mark , Barras Christen , Asadi Hamed
Published: August 2021

Background

Delivery of acute stroke endovascular intervention can be challenging because it requires complex coordination of patient and staff across many different locations. In this proof-of-concept paper we (a) examine whether WiFi fingerprinting is a feasible machine learning (ML)-based real-time location system (RTLS) technology that can provide accurate real-time location information within a hospital setting, and (b) hypothesize its potential application in streamlining acute stroke endovascular intervention.

Methods

We conducted our study in a comprehensive stroke care unit in Melbourne, Australia that offers a 24-hour mechanical thrombectomy service. ML algorithms including K-nearest neighbors, decision tree, random forest, support vector machine and ensemble models were trained and tested on a public WiFi dataset and the study hospital WiFi dataset. The hospital dataset was collected using the WiFi explorer software (version 3.0.2) on a MacBook Pro (AirPort Extreme, Broadcom BCM43x×1.0). Data analysis was implemented in the Python programming environment using the scikit-learn package. The primary statistical measure for algorithm performance was the accuracy of location prediction.

Results

ML-based WiFi fingerprinting can accurately predict the different hospital zones relevant in the acute endovascular intervention workflow such as emergency department, CT room and angiography suite. The most accurate algorithms were random forest and support vector machine, both of which were 98% accurate. The algorithms remain robust when new data points, which were distinct from the training dataset, were tested.

Conclusions

ML-based RTLS technology using WiFi fingerprinting has the potential to streamline delivery of acute stroke endovascular intervention by efficiently tracking patient and staff movement during stroke calls.
Elastic critical moment for monosymmetric beams under linear moment gradients
Authors: Xie Wenbin , Mohareb Magdi
Published: August 2021

The present study documents some inconsistencies observed when applying the lateral torsional buckling provisions of the Canadian standards of steel structures to characterize the elastic critical moments for monosymmetric beams subjected to linear moment gradients. An overview of the underlying theoretical background is presented and the reasons behind the discrepancies observed between standard-recommended solutions on one hand, and theoretical and finite element solutions on the other hand are discussed. An improved solution is then developed by generating a parametric study based on finite element analyses and developing regression equations to estimate the critical moments for monosymmetric beams under linear moments inducing double curvature. The expressions are cast in a dimensionless form as a function of four parameters. The potential use of the proposed solution is subsequently illustrated through a design example.
Implications of quantum gravity for dark matter
Authors: Calmet Xavier , Kuipers Folkert
Published: August 2021

In this essay, we show that quantum gravity and the spin-statistics theorem have very interesting consequences for dark matter candidates. Quantum gravity can lead to fifth force type interactions that lead to a lower bound on the masses of bosonic candidates. In the case of fermions, the spin-statistics theorem leads to a lower bound on fermion masses. For both bosonic and fermionic dark matter candidates, quantum gravity leads to a decay of dark matter particles. A comparison of their lifetime with the age of the universe leads to an upper bound on their masses. For singlet scalar dark matter fields, we find [Formula: see text].
Restrained geodetic domination of edge subdivision graph
Authors: Mulloor John Joy , Sangeetha V.
Published: August 2021

For a connected graph [Formula: see text], a set [Formula: see text] subset of [Formula: see text] is said to be a geodetic set if all vertices in G should lie in some [Formula: see text] geodesic for some [Formula: see text]. The minimum cardinality of the geodetic set is the geodetic number. In this paper, the authors discussed the geodetic number, geodetic domination number, and the restrained geodetic domination of the edge subdivision graph.
Parallel Minimum Cuts in Near-linear Work and Low Depth
Authors: Geissmann Barbara , Gianinazzi Lukas
Published: August 2021

We present the first
near-linear work
and
poly-logarithmic depth
algorithm for computing a
minimum cut
in an undirected graph. Previous parallel algorithms with poly-logarithmic depth required at least quadratic work in the number of vertices.

In a graph with
n
vertices and
m
edges, our randomized algorithm computes the minimum cut with high probability in
O
(
m
log
4
n
) work and
O
(log
3
n
) depth. This result is obtained by parallelizing a data structure that aggregates weights along paths in a tree, in addition exploiting the connection between minimum cuts and approximate maximum packings of spanning trees.

In addition, our algorithm improves upon bounds on the number of cache misses incurred to compute a minimum cut.