bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Testing of a Lattice Morphing Wing
Authors: Keidel Dominic , Lienhard Marc , Fasel Urban , Ermanni Paolo
Published: November 2020

This work presents the design, optimization and testing of a novel lattice-structure based morphing wing. The lattice-structure concept spans a large design space, including the possibility to vary among others material, number, distribution and the orientation of the lattice rods. The used parametrization scheme considers both the positioning of the Carbon Fiber Reinforced Polymer (CFRP) rods and their orientation in spherical coordinates within the wing, thus allowing to appropriately cover the design space, while reducing the set of variables during the design optimization procedure. The morphing deformations are relying on electromechanical servomotors. Design objectives include weight minimization and structural requirements, while achieving sufficient roll control.

The local deformation induced by the electromechanical actuators is distributed by an internal skeleton structure across the rear section of the wing. An extensible skin is ensuring a smooth cambering and minimizes the required actuation energy. The in-house developed and validated simulation environment couples the aerodynamic pressure and the structural deformations, to accurately predict the aeroelastic response of the wing to aerodynamic and actuation forces, considering large deformations. In addition to the lattice structure, the aeroelastic optimization also considers the actuation layout, and the layup-thickness of the wing skin. Planform and airfoil shape are fixed to a NACA0012 airfoil with 80 cm span, and 30 cm chord.

The structural and morphing behavior was evaluated on a technology demonstrator. The demonstrator provides large continuous shape changes, improving the aerodynamic performance and achieving large deflections and high rolling moment coefficients. This is mainly achieved by exploiting the interaction of the tailored internal structure and the actuation system. Since the deformation is distributed over a large portion of the wing, local stress concentrations are minimized, and actuation forces are reduced. Wing-up bending tests have been carried out, confirming the simulation results, respectively the load-carrying capability of the presented concept. Furthermore, actuation tests resulted in peak-to-peak trailing edge deflections of 31mm, respectively a rolling moment coefficient of 0.062, which are consistent with the simulation results and guarantee sufficient roll control.
Investigation and Attempt to 3D Print Piezoelectric 0-3 Composites Made of Photopolymer Resins and PZT
Authors: Mitkus Rytis , Pierou Andreas , Feder Julia , Sinapius Michael
Published: November 2020

The present study demonstrates the manufacturing and characterization of 0-3 piezoelectric composites made of up to 10 vol% of Lead Zirconate Titanate (PZT) particles and photopolymer resins. The tape-casting method was used to investigate the curing behavior, PZT loading limitations and the overall feasibility of the suspensions for 3D printing. Piezoelectric composites were 3D printed with a commercial DLP type 3D printer. As a starting point, the maximum possible vol% loading of PZT ceramic for each photopolymer resin was investigated. Five different commercially available photopolymer resins from Formlabs (Somerville, MA, US) were used. It was found that the addition of PZT particles to the photopolymer increases the time required for the photopolymer to solidify because PZT particles scatter the UV light. The approximate solidification time of each composition was measured, followed by viscosity measurements. SEM imaging of the composites showed good particle dispersion with minimum agglomeration, low particle sedimentation, but the weak bond between PZT particles and the photopolymers. Best performed material composition with 10 vol% of PZT was used for 3D printing. An attempt to shorten exposure time during printing was done by adding photoinitiator TPO. Suspensions with and without TPO were 3D printed and compared.
On the Effects of Electrical Conductivity on the Triboelectric Behavior of a PDMS-Based Composite Material
Authors: Zhao Xiaoyue , Dhanani Jai , Ounaies Zoubeida , Rashwan Ola
Published: November 2020

With the increasing demand for small and portable electronic devices, new energy conversion systems that can harvest energy from body motion and ambient environment are needed. Triboelectricity has recently become promising among the various energy conversion mechanisms because triboelectric devices can be small, flexible, and portable. The triboelectric output performance is closely related to the materials ‘properties employed. In this study, the effect of electrical conductivity on the electrical output of a triboelectric device is investigated experimentally. Experiments are conducted using a vertical contact/separation mode with polydimethylsiloxane (PDMS) based material as one of the contacting materials. The electrical conductivity of PDMS is tuned by adding two different weight percent of multiwall carbon nanotube (CNT): 10wt% CNT and 20wt% CNT. The relationship between electrical conductivity and the triboelectric output performance is obtained by correlating the open circuit voltage (Voc) and short circuit current (Isc) with the different weight percent CNT-PDMS materials. A maximum Voc of 98V and a maximum Isc of 3.2μA were obtained with the 20wt% CNT-PDMS and Teflon pair; this increase is likely due to the combination of enhanced triboelectric polarity difference and electrical conductivity. The optimum external resistance was also measured for the different CNT-PDMS weight percent materials. The maximum triboelectric output power reached 180μW at 80MΩ for the 20wt% CNT-PDMS and Teflon pair.
Magnetorheological Damper With Micro-Grooves: Design and Experiment
Authors: Liu Gaoyu , Gao Fei , Liao Wei-Hsin
Published: November 2020

Due to low power consumption and fast response, magnetorheological (MR) dampers are widely used in various engineering applications. To enhance the performances, efforts have been made to increase the field dependent force with the same power consumption. However, the fluid viscous force is also increased significantly, which is undesirable in practical use. To tackle this problem, the focus of this paper is to design and test a new MR damper with micro-grooves for performance enhancement.

First, the detailed design of the proposed MR damper is provided. A prototype of the new MR damper is fabricated. Silicon steel circular rings with thickness of 0.25 mm are installed around the damper piston to form two-layer micro-grooves. Experimental results of the two MR dampers without and with micro-grooves are then compared.

The advantages of MR damper with micro-grooves over the one without micro-grooves are validated. The damping force and controllable force range of MR damper with micro-grooves are larger than the one without micro-grooves. When designing MR damper, making micro-grooves can also decrease the increment of fluid viscous force while keeping the same increase of field dependent force. With micro-grooves, the field dependent force is increased by 92.7% with the same power consumption, while the fluid viscous force is increased by 43%.
Additively Manufactured Continuous Fibre-Reinforced Thermoplastics for Mechanisms Subjected to Predominant Inertial Load: A Case Study
Authors: Luzi Luca , Quercioli Giacomo , Pucci Riccardo , Bocchieri Guido , Vertechy Rocco , Berselli Giovanni
Published: November 2020

In the last decade, the adoption of additive manufacturing technologies (AMT) (3D printing) has increased significantly in many fields of engineering, initially only for rapid prototyping and more recently also for the production of finished parts. With respect to the long-established material subtractive technologies (MST), AMT is capable to overcome several limitations related to the shape realization of high-performance mechanical components such as those conceived via topology optimization and generative design approaches.

In the field of structures and mechanisms, a major advantage of AMT over MST is that, for the same loading and constraining conditions (including kinematic and overall encumbrance), it enables the realization of mechanical components with similar stiffness but smaller volume (thus smaller weight, density being equal).

Recently, the potentialities of AMT have also been increased by the introduction of the fuse filament deposition modeling (FDM) of continuous fibre-reinforced thermoplastics (CFRT), which combines the ease of processing of plastic AMT with the strength and specific modulus of the printed components that are comparable to those attainable via metallic AMT.

In this context, the present paper investigates the potentialities of FDM-CFRT for the realization of mechanisms subjected to predominant inertial loads such as those found in automated packaging machinery. As a case study a Stephenson six-bar linkage powered in direct drive by a permanent magnet synchronous motor is considered. Starting from an existing mechanism realized in aluminum alloy with traditional MST, a newer version to be realized with FDM-CFRT has been conceived by keeping the kinematics fixed and by redesigning the links via three-dimensional topology optimization. To provide a fair comparison with the more traditional design/manufacturing approach, size optimization of the original mechanism made in aluminum alloy has also been performed.

Comparison of the two versions of the mechanism highlights the superior performances of the one manufactured via FDM-CFRT in terms of weight, motor torque requirements and motion precision.
Analytical Modeling of a Segmented Bimorph Lithium Ion Battery Actuator
Authors: Gonzalez Cody , Shan Shuhua , Frecker Mary , Rahn Christopher
Published: November 2020

Silicon composite anode-based lithium ion battery actuators have strong potential for large actuation strain, complex shape change, and large compliance tunability. This allows for actuators with potential to do work with no energy expenditure beyond parasitic losses to internal resistance. This paper studies a segmented bimorph actuator comprised of a silicon-based composite anode double-side coated on copper foil.

The bimorph design allows for a nearly 360° range of motion in transverse bending and can double the capacity of the battery in comparison to a single side coated unimorph design. An Euler-Bernoulli model is developed to predict free deflection for a range of geometric configurations and states of charge of the bimorph. By modeling the charging of both active sides of the bimorph simultaneously, it is possible to achieve zero bending while still accommodating for the volumetric expansion of the silicon. The bimorph is able to achieve actuation in one given direction by charging each anode coating separately or maintaining a charge difference between the two coatings. The former method allows for the accommodated volumetric expansion of silicon while maintaining zero bending as in a conventional battery setup. The latter method allows for larger battery capacity and range of motion for a novel electrochemically-based actuation mechanism.
Analysis of Multi-Stable Architectures for Morphing Structures
Authors: Erol Anil , Baur Jeffery
Published: November 2020

The field of multi-stable structures has been steadily growing due to a wide range of potential applications including energy harvesting, MEMS, and mechanical logic. This work focuses on utilizing elastic energy trapping and snap-through phenomena of bistable unit cells to design a latticed, hierarchical multi-stable cylinder that can articulate up to 30 degrees from its center axis. The employment of bistable elements is hypothesized to reduce the total strain energy required to articulate the cylinder, and yield faster responses with the snap-through. While multi-stable cylinders exist in previous studies, there have been no previous attempts at studying different modes of deformation beyond compressive loading. Thus, the current work presents a new problem regarding the effects of bistable elements in a latticed cylinder that is carrying tensile, compressive, and shear loadings and exhibiting large displacements as the cylinder is articulated.. The total strain energy density of the articulating cylinder is investigated as a function of the heights of the unit cells, which aids in determining an ideal height for the design that minimizes the strain energy density. Results show that the strain energy of an articulating cylinder can be minimized with the use of multi-stability, and that a multi-stable cylinder can require up to three times less loads to maintain desired articulation compared to a mono-stable structure. These results will lead to future works on further optimizing the articulating cylinder by varying additional parameters like the individual heights of rows, the thicknesses of unit cell beams, the strain energy density, and the initial loading threshold for articulation. In addition, the work in this study can yield methodologies for designing arbitrarily morphing skins beyond just cylindrical geometries.
A Lumped Parameter Approach for Analysing a Metamaterial Beam Based Piezoelectric Energy Harvester Around Fundamental Resonance
Authors: Hu Guobiao , Tang Lihua , Yang Yaowen
Published: November 2020

This paper proposes a lumped parameter approach to simplify the modelling of a metamaterial based PEH to predict its energy harvesting performance around the fundamental resonance. The metamaterial based PEH consists of a host beam with a piezoelectric patch bonded at the clamped end. A series of local resonators are attached onto the host beam. In the first case study, the local resonators are modelled as mass-spring systems. By applying Rayleigh’s method and approximating the fundamental mode shape by the static deflection, the host beam is represented by a SDOF system. The equivalent lumped parameters are assumed to concentrate at the tip of the host beam and their explicit expressions are presented. Though the local resonators are identical, they have different influences on the host beam when being attached at different positions. To reflect the interaction degree (i.e., reacting force) between the local resonator and the host beam, a scaling factor that is a function of the attaching position is derived. On the other hand, due to the action of the local resonators, the fundamental mode shape of the host beam is actually changed. Based on the linear superposition principle, the static deflection approximated fundamental mode shape is corrected and the electromechanical coupling coefficient that is sensitive to the slope of the mode shape is updated to improve the accuracy. Based on the derived equivalent lumped parameters and correction factors, a multiple-degree-of-freedom (MDOF) model is constructed to predict the dynamic behavior of the metamaterial based PEH with mass-spring resonators. A corresponding finite element model is built to verify the developed MDOF model. In the second case study, the local resonators are modelled as practical parasitic beams. The parasitic beams are converted into equivalent lumped systems as well. However, the lumped parameters are the effective parameters at the beam tip. For the force interaction at the root of a parasitic beam, a factor is derived to correct the reaction force when a parasitic beam is represented by a SDOF mass-spring system. Using the reaction force correction factor, a MDOF model for the metamaterial based PEH with beam-like resonators is also established and verified by the finite element model.
High Genetic Diversity in Flavobacterium psychrophilum Isolates from Healthy Rainbow Trout (Oncorhynchus mykiss) Farmed in the Same Watershed, Revealed by Two Typing Methods
Authors: Calvez Ségolène , Navarro-Gonzalez Nora , Siekoula-Nguedia Charlène , Fournel Catherine , Duchaud Eric
Published: November 2020

The bacterium
Flavobacterium psychrophilum
is a serious pathogen in many fish species, especially salmonids, that is responsible for considerable economic losses worldwide. In order to treat infections and to develop vaccines, the genetic diversity of this bacterium needs to be known. We assessed the genetic diversity of
F. psychrophilum
isolates from apparently healthy rainbow trout raised in several fish farms in the same watershed in France. Two different genotyping methods revealed high diversity. The majority of isolates were unrelated to clonal complex sequence type 10 (CC-ST10), the clonal complex that is predominant worldwide and associated with disease in rainbow trout. In addition, we found 13 novel sequence types. These results suggest that a diverse subpopulation of
F. psychrophilum
may be harbored by rainbow trout.
Regulator RcsB Controls Prodigiosin Synthesis and Various Cellular Processes in Serratia marcescens JNB5-1
Authors: Pan Xuewei , Tang Mi , You Jiajia , Liu Fei , Sun Changhao , Osire Tolbert , Fu Weilai , Yi Ganfeng , Yang Taowei , Yang Shang-Tian , Rao Zhiming
Published: November 2020

RcsB is a two-component response regulator in the Rcs phosphorelay system, and it plays versatile regulatory functions in
Enterobacteriaceae
. However, information on the function of the RcsB protein in bacteria, especially in
S. marcescens
, remains limited. In this work, we illustrated experimentally that the RcsB protein was involved in diverse cellular processes in
S. marcescens
, including prodigiosin synthesis, cell motility, capsular polysaccharide production, biofilm formation, and acid resistance. Additionally, the regulatory mechanism of the RcsB protein in these cellular processes was investigated. In conclusion, this work indicated that RcsB could be a regulator for prodigiosin synthesis and provides insight into the function of the RcsB protein in
S. marcescens
.
Despite Excellent Test Characteristics of the cobas 4800 CT/NG Assay, Detection of Oropharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae Remains Challenging
Authors: van Niekerk J. M. , van der Veer B. M. J. W. , Hoebe C. J. P. A. , van de Bovenkamp J. , van Herk C. , van Loo I. H. M. , van Alphen L. B. , Wolffs P. F. G.
Published: November 2020

Oropharyngeal
Chlamydia trachomatis
(CT) infections and, especially,
Neisseria gonorrhoeae
(NG) infections are common, but few commercial nucleic acid amplification tests (NAATs) specify extragenital samples for intended use. The test characteristics of the cobas 4800 CT/NG assay were evaluated for oropharyngeal swabs. The technical validation included analysis of the specificity, sensitivity, dynamic range, linearity, efficiency, and precision. The probability of detection curve combined with historical data enabled the estimation of potentially missed diagnoses.
Complete Genome Sequences of Walnut-Associated
Xanthomonas euroxanthea
Strains CPBF 367 and CPBF 426 Obtained by Illumina/Nanopore Hybrid Assembly
Authors: Teixeira Miguel , Martins Leonor , Fernandes Camila , Chaves Cátia , Pinto Joana , Tavares Fernando , Fonseca Nuno A.
Published: November 2020

We present the complete genome sequences of two
Xanthomonas euroxanthea
strains isolated from buds of a walnut tree. The whole-genome sequences of strains CPBF 367 and CPBF 426 consist of two circular chromosomes of 4,923,218 bp and 4,883,254 bp and two putative plasmids of 45,241 bp and 17,394 bp, respectively. These data may contribute to the understanding of
Xanthomonas
species-specific adaptations to walnut.
Complete Genome Sequences of Two Strains of Francisella tularensis subsp.
holarctica
bv. japonica
Authors: Hotta Akitoyo , Fujita Osamu , Tanabayashi Kiyoshi , Uda Akihiko , Shindo Junji , Park Chun-Ho , Sato Hisaaki , Suzuki Michio , Morikawa Shigeru , Maeda Ken
Published: November 2020

Francisella tularensis
, a highly infectious bacterium, is an etiological agent of the zoonotic disease tularemia. It is widely distributed in the Northern Hemisphere, including Japan. Here, we have determined the complete genome sequences of two strains of
F. tularensis
subsp.
holarctica
bv. japonica isolated from hares in 2008 and 2009.
Draft Genome Sequence of the Carboxydotrophic Alphaproteobacterium Aminobacter carboxidus Type Strain DSM 1086
Authors: Turrini Paolo , Artuso Irene , Tescari Marco , Lugli Gabriele Andrea , Frangipani Emanuela , Ventura Marco , Visca Paolo
Published: November 2020

Aminobacter carboxidus
is a soil Gram-negative alphaproteobacterium belonging to the physiological group of carboxydobacteria which aerobically oxidize CO to CO
2
. Here, we report the draft genome sequence of the
A. carboxidus
DSM 1086 type strain and the identification of both form I and form II CO dehydrogenase systems in this strain.
Oral rehabilitation of a cleft palate patient with tooth-supported, telescopic magnetic overdenture
Authors: Alfarsi Mohammed A , Shaik Sharaz
Published: November 2020

A 49-year-old male patient with residual cleft palate and missing pre-maxilla presented with an ill-fitting and unaesthetic maxillary denture. The posterior teeth were periodontally sound but crowded and had defective restorations and secondary caries. We restored the bilateral maxillary canines and first premolars with conical telescopic crowns having magnetic keepers. A metal-reinforced acrylic overdenture with magnetic attachments corresponding to the keepers of the telescopic crowns was fabricated. The telescopic crowns provided a single path of insertion, retention and stability to the prosthesis. The magnetic attachments provided additional retention and self-centring properties. The prosthesis effectively sealed the oronasal communication and enhanced the function, aesthetics and oral hygiene. The 6-month and 1-year follow-ups revealed that the patient was delighted, and the prosthesis provided excellent obturation and function. Periodic follow-up, maintenance, patient education and meticulous oral hygiene are vital for long-term success of such prostheses.
Rapidly progressive vision loss due to fulminant idiopathic intracranial hypertension: a diagnostic and management dilemma
Authors: Sutraye Jagadeesh , Kannam Mohan , Kapoor Rajat , Sachdeva Virender
Published: November 2020

A 44-year-old obese woman presented with decrease in vision in the right eye (RE) for 3 days. She reported a simultaneous onset of holocranial headache that worsened on bending forward. She denied eye pain, pain on eye movements, and other ocular or neurological complaints. On examination, her distance best-corrected visual acuity was counting fingers at 1 m in the RE and 20/20 in the left eye (LE). Colour vision was subnormal in both eyes (BE). There was grade II relative afferent pupillary defect in the RE. Fundus examination showed disc oedema in BE . Visual fields in the LE showed central scotoma extending nasally. A provisional diagnosis of papillitis was considered. However, contrast-enhanced MRI of the brain and orbits showed evidence of elevated intracranial pressure. Cerebrospinal fluid (CSF) opening pressure was 42 cm H2O while rest of the CSF analysis was normal. Diagnosis was revised to fulminant idiopathic intracranial hypertension. Management with medical therapy and urgent thecoperiteoneal shunt improved visual function in BE.
Autoimmune switch from hyperthyroidism to hypothyroidism in Graves’ disease
Authors: Padmanaban Preethi , Jain Rohit
Published: November 2020

We report a case of a 21-year-old young woman who was initially diagnosed with hyperthyroidism secondary to Graves’ disease and spontaneously switched to hypothyroidism in a year. While most autoimmune hypothyroidism is due to Hashimoto’s disease, in her case, we suspect that her hypothyroidism is due to a switch of antibody dominance from thyroid stimulating hormone (TSH) receptor-stimulating antibody (TS Ab) to TSH receptor-blocking antibody (TB Ab). Switching from dominant TS Ab activity to dominant TB Ab activity is a rare phenomenon. Optimal management of this condition is not known. Loss of follow-up and medication non-adherence has made medical management in this young woman of reproductive age further challenging.
Staphylococcus schleiferidiabetic foot osteomyelitis and bacteraemia in an immunocompromised host
Authors: Nguyen Minh Thu Thi , Ahern Nicholas R , Train Meghan K
Published: November 2020

Staphylococcus schleiferiis a Gram-positive coccus bacterium first discovered in 1988 that is typically associated with skin and ear infections in dogs, cats and birds. It is infrequently described as a human pathogen. There are, however, emerging reports ofS. schleiferiinfections in diverse clinical scenarios in humans, particularly in patients with weakened immune systems.S. schleiferimay be underrecognised due to limitations in routine microbiology diagnostic protocols and mislabelling as otherStaphylococcussp. We present a rare case ofS. schleiferidiabetic foot osteomyelitis with subsequent bacteraemia in an immunocompromised host.
Bilateral, vertical supranuclear gaze palsy following unilateral midbrain infarct
Authors: Yang Yunfei , Qidwai Umair , Burton Benjamin J L , Canepa Carlo
Published: November 2020

A 60-year-old man recently admitted for bipedal oedema, endocarditis and a persistently positive COVID-19 swab with a history of anticoagulation on rivaroxaban for atrial fibrillation, transitional cell carcinoma, cerebral amyloid angiopathy, diabetes and hypertension presented with sudden onset diplopia and vertical gaze palsy. Vestibulo-ocular reflex was preserved. Simultaneously, he developed a scotoma and sudden visual loss, and was found to have a right branch retinal artery occlusion. MRI head demonstrated a unilateral midbrain infarct. This case demonstrates a rare unilateral cause of bilateral supranuclear palsy which spares the posterior commisure. The case also raises a question about the contribution of COVID-19 to the procoagulant status of the patient which already includes atrial fibrillation and endocarditis, and presents a complex treatment dilemma regarding anticoagulation.
Bone turnover and metabolite responses to exercise in people with and without long-duration type 1 diabetes: a case–control study
Authors: Taylor Guy S , Moser Othmar , Smith Kieran , Shaw Andy , Tang Jonathan C Y , Fraser William D , Eckstein Max L , Aziz Faisal , Stevenson Emma J , Shaw James A , West Daniel J
Published: November 2020

Introduction

Exercise acutely alters markers of bone resorption and formation. As risk of fracture is increased in patients with type 1 diabetes, understanding if exercise-induced bone turnover is affected within this population is prudent. We assessed bone turnover responses to acute exercise in individuals with long-duration type 1 diabetes and matched controls.

Research design and methods

Participants with type 1 diabetes (n=15; age: 38.7±13.3; glycosylated hemoglobin: 60.5±6.7 mmol/mol; diabetes duration: 19.3±11.4 years) and age-matched, fitness-matched, and body mass index-matched controls (n=15) completed 45 min of incline walking (60% peak oxygen uptake). Blood samples were collected at baseline and immediately, 30 min, and 60 min postexercise. Markers of bone resorption (β-C-terminal cross-linked telopeptide of type 1 collagen, β-CTx) and formation (procollagen type-1 amino-terminal propeptide, P1NP), parathyroid hormone (PTH), phosphate, and calcium (albumin-adjusted and ionized) were measured. Data (mean±SD) were analyzed by a mixed-model analysis of variance.

Results

Baseline concentrations of P1NP and β-CTx were comparable between participants with type 1 diabetes and controls. P1NP did not change with exercise (p=0.20) but β-CTx decreased (p<0.001) in both groups, but less so in participants with type 1 diabetes compared with controls (−9.2±3.7%; p=0.02). PTH and phosphate increased immediately postexercise in both groups; only PTH was raised at 30 min postexercise (p<0.001), with no between-group differences (p>0.39). Participants with type 1 diabetes had reduced albumin and ionized calcium at all sample points (p<0.01).

Conclusions

Following exercise, participants with type 1 diabetes displayed similar time-course changes in markers of bone formation and associated metabolites, but an attenuated suppression in bone resorption. The reduced albumin and ionized calcium may have implications for future bone health. Further investigation of the interactions between type 1 diabetes, differing modalities and intensities of exercise, and bone health is warranted.
Microscopic hematuria is a risk factor for end-stage kidney disease in patients with biopsy-proven diabetic nephropathy
Authors: Okada Sadanori , Samejima Ken-ichi , Matsui Masaru , Morimoto Katsuhiko , Furuyama Riri , Tanabe Kaori , Eriguchi Masahiro , Akai Yasuhiro , Saito Yoshihiko , Tsuruya Kazuhiko
Published: November 2020

Introduction

There are fewer reports about whether the presence of hematuria affects the progression of chronic kidney disease in patients with diabetic nephropathy. We analyzed whether microscopic hematuria in diabetic nephropathy is a risk factor for end-stage kidney disease (ESKD).

Research design and methods

The present study was a retrospective cohort study of patients with biopsy-proven diabetic nephropathy. We recruited 397 patients with diabetic nephropathy, which was confirmed by renal biopsy between June 1981 and December 2014 and followed them until October 2018 or death. Patients with microscopic hematuria before renal biopsy were defined as the hematuria group (n=91), and the remainder as the no-hematuria group (n=306). The main outcome was the occurrence of ESKD, which was defined by the requirement of permanent renal replacement therapies.

Results

The systolic and diastolic blood pressure, serum creatinine and proteinuria were significantly higher, and the estimated glomerular filtration rate was significantly lower in the hematuria group compared with the no-hematuria group. Pathological evaluations revealed that glomerular, tubulointerstitial and vascular lesions in the hematuria group were significantly more severe. During a median of 10.1 years, 44 and 52 patients developed ESKD in the hematuria group and the no-hematuria group, respectively. Survival analyses showed that the incidence of ESKD was significantly higher in the hematuria group compared with the no-hematuria group (log-rank, p<0.0001). The multivariable Cox proportional hazards models revealed a significant association between hematuria and the incidence of ESKD after adjusting for clinically relevant factors, including proteinuria and renal pathology (adjusted HR 1.64, 95% CI 1.03 to 2.60). The subgroups of men, proteinuria ≥0.5 g/day, and systolic blood pressure ≥132 mm Hg showed a stronger association between hematuria and ESKD than their opposing subgroups.

Conclusions

Microscopic hematuria is a risk factor for ESKD in diabetic nephropathy, independent of proteinuria and renal pathology.
Comparative effectiveness of treatment modalities in non-metastatic gastric adenocarcinoma: a propensity score matching analysis of the National Cancer Database
Authors: Barzi Afsaneh , Yang Dongyun , Kim Anthony W , Shah Manish A , Sadeghi Sarmad
Published: November 2020

Background

While addition of chemotherapy and radiation to surgery improves the outcomes of non-metastatic gastric adenocarcinoma (GAC), the best treatment strategy remains controversial.

Methods

To determine the effectiveness of different strategies in patients with curative surgery, we performed an analysis of GAC patients in National Cancer Database. Propensity score method was used to control for imbalances in the confounders. Overall survival (OS), the primary outcome, was analysed using Cox proportional hazard model and Kaplan-Meier curves.

Results

Patients diagnosed with GAC, from 2004 to 2013, were included in this analysis and grouped according to their treatment: surgery alone (15 184), chemoradiation in the neoadjuvant (6000) or adjuvant setting (7953), and perioperative chemotherapy (PCh; 3745) or adjuvant chemotherapy (ACh; 3000). Compared with surgery alone, all adjunctive therapies resulted in an improvement in OS; neoadjuvant chemoradiation (NACRT): HR 0.9 (95% CI: 0.84 to 0.97), PCh: HR 0.73 (95% CI: 0.68 to 0.79), adjuvant chemoradiation (ACRT): HR 0.71 (95% CI: 0.67 to 0.75), and ACh: HR 0.86 (95% CI: 0.8 to 0.93). Excluding patients with surgery only, we compared different strategies to PCh. In patients with distal GAC, ACRT resulted in improved OS, (HR 0.89; 95% CI: 0.796 to 0.996), p=0.042. In patients with proximal GAC, NACRT was inferior to PCh, HR 1.101 (95% CI: 1.006 to 1.204), p=0.036.

Conclusion

In this real world population, addition of chemotherapy and radiation to surgery was associated with better OS. Radiation therapy may have a role in patients with distal GAC. Future research can elucidate patient, tumour, and treatment factors that necessitate the inclusion and sequence of radiation therapy in this population.
Bringing a health systems modelling approach to complex evaluations: multicountry applications in HIV, TB and malaria
Authors: Phillips David E , Ambrosio Guillermo , Batzel Audrey , Cerezo Carmen , Duber Herbert , Faye Adama , Gaye Ibrahima , Hernández Prado Bernardo , Huntley Bethany , Kestler Edgar , Kingongo Constant , Lim Stephen S , Linebarger Emily , Matute Jorge , Mpanya Godefroid , Mulongo Salva , O'Brien-Carelli Caitlin , Palmisano Erin , Rios Casas Francisco , Shelley Katharine , Tine Roger , Whitaker Daniel , Ross Jennifer M
Published: November 2020

Introduction

Understanding how to deliver interventions more effectively is a growing emphasis in Global Health. Simultaneously, health system strengthening is a key component to improving delivery. As a result, it is challenging to evaluate programme implementation while reflecting real-world complexity. We present our experience in using a health systems modelling approach as part of a mixed-methods evaluation and describe applications of these models.

Methods

We developed a framework for how health systems translate financial inputs into health outcomes, with in-country and international experts. We collated available data to measure framework indicators and developed models for malaria in Democratic Republic of the Congo (DRC), and tuberculosis in Guatemala and Senegal using Bayesian structural equation modelling. We conducted several postmodelling analyses: measuring efficiency, assessing bottlenecks, understanding mediation, analysing the cascade of care and measuring subnational effectiveness.

Results

The DRC model indicated a strong relationship between shipment of commodities and utilisation thereof. In Guatemala, the strongest model coefficients were more evenly distributed. Results in Senegal varied most, but pathways related to community care had the strongest relationships. In DRC, we used model results to estimate the end-to-end cost of delivering commodities. In Guatemala, we used model results to identify potential bottlenecks and understand mediation. In Senegal, we used model results to identify potential weak links in the cascade of care, and explore subnationally.

Conclusion

This study demonstrates a complementary modelling approach to traditional evaluation methods. Although these models have limitations, they can be applied in a variety of ways to gain greater insight into implementation and functioning of health service delivery.
Subsidise the test, the treatment or both? Results of an individually randomised controlled trial of the management of suspected malaria fevers in the retail sector in western Kenya
Authors: Laktabai Jeremiah , Saran Indrani , Zhou Yunji , Simmons Ryan A , Turner Elizabeth L , Visser Theodoor , O'Meara Wendy
Published: November 2020

Introduction

In many malaria-endemic countries, the private retail sector is a major source of antimalarial drugs. However, the rarity of malaria diagnostic testing in the retail sector leads to overuse of the first-line class of antimalarial drugs known as artemisinin-combination therapies (ACTs). The goal of this study was to identify the combination of malaria rapid diagnostic test (RDT) and ACT subsidies that maximises the proportion of clients seeking care in a retail outlet that choose to purchase an RDT (RDT uptake) and use ACTs appropriately.

Methods

842 clients seeking care in 12 select retail outlets in western Kenya were recruited and randomised into 4 arms of different combinations of ACT and RDT subsidies, with ACT subsidies conditional on a positive RDT. The outcomes were RDT uptake (primary) and appropriate and targeted ACT use (secondary). Participants’ familiarity with RDTs and their confidence in test results were also evaluated.

Results

RDT uptake was high (over 96%) across the study arms. Testing uptake was 1.025 times higher (98% CI 1.002 to 1.049) in the RDT subsidised arms than in the unsubsidised groups. Over 98% of clients were aware of malaria testing, but only 35% had a previous experience with RDTs. Nonetheless, confidence in the accuracy of RDTs was high. We found high levels of appropriate use and targeting of ACTs, with 86% of RDT positives taking an ACT, and 93.4% of RDT negatives not taking an ACT. The conditional ACT subsidy did not affect the RDT test purchasing behaviour (risk ratio: 0.994; 98% CI 0.979 to 1.009).

Conclusion

Test dependent ACT subsidies may contribute to ACT targeting. However, in this context, high confidence in the accuracy of RDTs and reliable supplies of RDTs and ACTs likely played a greater role in testing uptake and adherence to test results.
WeChat-based health education to improve health knowledge in three major infectious diseases among residents: a multicentre case-controlled protocol
Authors: Qiu Yan , Qin Hongli , Ying Meike , Xu Kaijin , Ren Jingjing
Published: November 2020

Introduction

Health literacy (HL) in infectious diseases is inadequate in China. Since the first nationwide survey of HL conducted in China, great efforts have been made. However, the rate of HL in infectious diseases was 16.06% in 2017. In contrast, with an HL rate of 15.85% in 2008, no significant effect was observed over 10 years. With an increasing number of internet users, we aim to assess the effects of WeChat-based health education for the promotion of partial HL-health knowledge in infectious diseases.

Methods and analysis

A total of 2160 residents aged 15–69 years old will be enrolled in this study. The primary outcome measures will be the rate of health knowledge in infectious disease. The follow-up period is 3 years.

Ethics and dissemination

The study protocol was approved by the Research Ethics Committee of the First Affiliated Hospital, College of Medicine, Zhejiang University. The findings of this study will be submitted to a peer-reviewed journal.
Multilevel predictors of controlled CD4 count and blood pressure in an integrated chronic disease management model in rural South Africa: a panel study
Authors: Ameh Soter , Gómez-Olivé Francesc X , Kahn Kathleen , Tollman Stephen , Klipstein-Grobusch Kerstin
Published: November 2020

Objective

In 2011, The National Department of Health introduced the Integrated Chronic Disease Management (ICDM) model as a pilot programme in selected primary healthcare facilities in South Africa. The objective of this study was to determine individual-level and facility-level predictors of controlled CD4 count and blood pressure (BP) in patients receiving treatment for HIV and hypertension, respectively.

Design

A panel study.

Setting and participants

This study was conducted in the Bushbuckridge Municipality, South Africa from 2011 to 2013. Facility records of patients aged ≥18 years were retrieved from the integrated chronic disease management (ICDM) pilot (n=435) and comparison facilities (n=443) using a three-step probability sampling process. CD4 count and BP control are defined as CD4 count >350 cells/mm3 and BP <140/90 mm Hg. A multilevel Least Absolute Shrinkage and Selection Operator binary logistic regression analysis was done at a 5% significance level using STATA V.16.

Primary outcome measures

CD4 (cells/mm3) count and BP (mm Hg).

Results

Compared with the comparison facilities, patients receiving treatment in the pilot facilities had increased odds of controlling their CD4 count (OR=5.84, 95% CI 3.21–8.22) and BP (OR=1.22, 95% CI 1.04–2.14). Patients aged 50–59 (OR=6.12, 95% CI 2.14–7.21) and ≥60 (OR=7.59, 95% CI 4.75–11.82) years had increased odds of controlling their CD4 counts compared with those aged 18–29 years. Likewise, patients aged 40–49 (OR=5.73, 95% CI 1.98–8.43), 50–59 (OR=7.28, 95% CI 4.33–9.27) and ≥60 (OR=9.31, 95% CI 5.12–13.68) years had increased odds of controlling their BP. In contrast, men had decreased odds of controlling their CD4 count (OR=0.12, 95% CI 0.10–0.46) and BP (OR=0.21, 95% CI 0.19–0.47) than women.

Conclusion

The ICDM model had a small but significant effect on BP control, hence, the need to more effectively leverage the HIV programme for optimal BP control in the setting.
Qualitative investigation of trace-based communication: how are traces conceptualised in healthcare teamwork?
Authors: Cristancho Sayra , Field Emily
Published: November 2020

Objectives

This interview-based qualitative study aims to explore how healthcare providers conceptualise trace-based communication and considers its implications for how teams work. In the biological literature, trace-based communication refers to the non-verbal communication that is achieved by leaving ‘traces’ in the environment and other members sensing them and using them to drive their own behaviour. Trace-based communication is a key component of swam intelligence and has been described as a critical process that enables superorganisms to coordinate work and collectively adapt. This paper brings awareness to its existence in the context of healthcare teamwork.

Design

Interview-based study using Constructivist Grounded Theory methodology.

Setting

This study was conducted in multiple team contexts at one of Canada’s largest acute-care teaching hospitals.

Participants

25 clinicians from across professions and disciplines. Specialties included surgery, anesthesiology, psychiatry, internal medicine, geriatrics, neonatology, paramedics, nursing, intensive care, neurology and emergency medicine.

Intervention

Not relevant due to the qualitative nature of the study.

Primary and secondary outcome

Not relevant due to the qualitative nature of the study.

Results

The dataset was analysed using the sensitising concept of ‘traces’ from Swarm Intelligence. This study brought to light novel and unique elements of trace-based communication in the context of healthcare teamwork including focused intentionality, successful versus failed traces and the contextually bounded nature of the responses to traces. While participants initially felt ambivalent about the idea of using traces in their daily teamwork, they provided a variety of examples. Through these examples, participants revealed the multifaceted nature of the purposes of trace-based communication, including promoting efficiency, preventing mistakes and saving face.

Conclusions

This study demonstrated that clinicians pervasively use trace-based communication despite differences in opinion as to its implications for teamwork and safety. Other disciplines have taken up traces to promote collective adaptation. This should serve as inspiration to at least start exploring this phenomenon in healthcare.
Does electronic consent improve the logistics and uptake of HPV vaccination in adolescent girls? A mixed-methods theory informed evaluation of a pilot intervention
Authors: Chantler Tracey , Pringle Ellen , Bell Sadie , Cooper Rosie , Edmundson Emily , Nielsen Heidi , Roberts Sheila , Edelstein Michael , Mounier-Jack Sandra
Published: November 2020

Objectives

To evaluate the usability and acceptability of an electronic consent pilot intervention for school-based immunisations and assess its impact on consent form returns and human papilloma virus (HPV) vaccine uptake.

Design

Mixed-methods theory-informed study applying qualitative methods to examine the usability and acceptability of the intervention and quantitative methods to assess its impact.

Setting and participants

The intervention was piloted in 14 secondary schools in seven London boroughs in 2018. Intervention schools were matched with schools using paper consent based on the proportion of students with English as a second language and students receiving free school meals. Participants included nurses, data managers, school-link staff, parents and adolescents.

Interventions

An electronic consent portal where parents could record whether they agreed to or declined vaccination, and nurses could access data to help them manage the immunisation programme.

Primary and secondary outcome measures

Comparison of consent form return rates and HPV vaccine uptake between intervention and matched schools.

Results

HPV vaccination uptake did not differ between intervention and matched schools, but timely consent form return was significantly lower in intervention schools (73.3% vs 91.6%, p=0.008). The transition to using electronic consent was not straightforward, while schools and staff understood the potential benefits, they found it difficult to adapt to new ways of working which removed some level of control from schools. Reasons for lower consent form return in e-consent schools included difficulties encountered by some parents in accessing and using the intervention. Adolescents highlighted the potential for electronic consent to by-pass their information needs.

Conclusions

The pilot intervention did not improve consent form return or vaccine uptake due to challenges encountered in transitioning to new working practice. New technologies require embedding before they become incorporated in everyday practice. A re-evaluation once stakeholders are accustomed with electronic consent may be required to understand its impact.
TOP-ID: a Delphi technique-guided development of a prescription and deprescription tool for adults with intellectual disabilities
Authors: Lonchampt Sophie , Gerber Fabienne , Aubry Jean-Michel , Desmeules Jules , Besson Marie , Markus Kosel
Published: November 2020

Objectives

Adults with an intellectual disability (AWID) are often polymedicated because of somatic and psychiatric health problems. Besides, they may display challenging behaviours, leading to off-label prescription of psychotropic drugs, without efficacy and with numerous adverse effects. In this context, a prescription/deprescription tool (Tool for Optimising Prescription in Intellectual Disability/TOP-ID) was developed to improve the care of AWID. This paper describes how TOP-ID was designed.

Design

Four-step consensus-based process involving a review of the literature, eight semistructured interviews and a two-round Delphi process.

Setting

Seventeen general practices and university and general hospitals from Belgium, France and Switzerland.

Participants

Eighteen French-speaking physicians from different domains of expertise participated in the Delphi process.

Primary and secondary outcome measures

For the Delphi iteration process, consensus was defined as at least a 65% agreement between the experts.

Results

Two rounds were needed for the Delphi process. Eighty-one items of the tool were submitted to 18 out of 35 recruited French-speaking experts during the first round. Sixty-nine per cent of the items reached a rate of agreement of 65% or more in that round. Thirteen questions were reformulated and resubmitted for the second Delphi iteration round. All of the statements reached a rate of agreement of 65% or more in the second round.

Conclusion

TOP-ID is the first prescription–deprescription tool developed specifically for AWIDs in French. It is intended to help prescribers document patient care in order to reduce prescription errors and to improve safety. The next steps of the project include the development of an electronic version of TOP-ID and a utility study.