bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of Extracellular Matrix Rigidity Via Riboflavin‐mediated Photocrosslinking Regulates Invasive Motility and Treatment Response in a 3D Pancreatic Tumor Model
Authors: Jafari Rojin , Cramer Gwendolyn M. , Celli Jonathan P.
Published: December 2019

In this study, we evaluate the use of riboflavin‐mediated collagen photocrosslinking as an experimental tool to modulate extracellular matrix (ECM) mechanical properties in 3D in vitro tumor models. Using this approach in conjunction with 3D pancreatic tumor spheroid transplants, we show that the extent of matrix photocrosslinking in reconstituted hydrogels with fixed protein concentration scales inversely with the extent of invasive progression achieved by cells infiltrating into the surrounding ECM from primary transplanted spheroids. Using cross‐linking to manipulate the extent of invasion into ECM in conjunction with imaging‐based treatment assessment, we further leverage this approach as a means for assaying differential therapeutic response in primary nodule and ECM‐invading populations and compare response to verteporfin‐based photodynamic therapy (PDT) and oxaliplatin chemotherapy. Treatment response data shows that invading cell populations (which also exhibit markers of increased EMT) are highly chemoresistant yet have significantly increased sensitivity to PDT relative to the primary nodule. In contrast, the oxaliplatin treatment achieves greater growth inhibition of the primary nodule. These findings may be significant in themselves, while the methodology developed here could have a broader range of applications in developing strategies to target invasive disease and/or mecahanobiological determinants of therapeutic response in solid tumors.
Modelling factors for Aboriginal and Torres Strait Islander child neurodevelopment outcomes: A latent class analysis
Authors: Strobel Natalie A. , Richardson Alice , Shepherd Carrington C. J. , McAuley Kimberley E. , Marriott Rhonda , Edmond Karen M. , McAullay Daniel R.
Published: December 2019

Background

The Australian Early Development Census (AEDC) provides a measure of early child development upon school entry. Understanding which combination of factors influences Aboriginal child neurodevelopment is important to inform policy and practice.

Objective

The primary objective was to use latent class analysis (LCA) to model AEDC profiles and identify the highest need profiles. The secondary objective was to determine the associations of these high need profiles on the likelihood of a child becoming developmentally vulnerable.

Methods

We designed a prospective population‐based birth cohort study (n = 2715) using linked data sets with information on Aboriginal cohort children, and their mothers and siblings in Western Australia. Specific developmental indicators in the 2009 and 2012 AEDC were used to assess developmental vulnerability. LCA methods were used to determine need profiles and their association with developmental vulnerability.

Results

49.3% of Aboriginal children were vulnerable on at least one developmental domain, and 37.5% were vulnerable on two or more domains. LCA found six unique profiles. High needs family, High needs young mother, and Preterm infant comprised 42% of the cohort and were considered to have high need configurations. These groups were at least 1.7 times as likely to have children who had at least one or two developmental vulnerabilities compared with the Healthy family group.

Conclusion

Many Aboriginal children in Western Australia enter school with at least one developmental vulnerability. This study highlights a range of unique profiles that can be used to empower Aboriginal families for change and develop targeted programmes for improving the early development of young Aboriginal children.
Diverse social movement coalitions: Prospects and challenges
Authors: Gawerc Michelle I.
Published: December 2019

Coalitions are among the most important tactical tools available for social movements and civil resistance campaigns, as they enable the sharing of networks, resources, expertise, and information, while simultaneously projecting an image of power through unity and numbers. Though exceptionally challenging to build, diverse coalitions are viewed by many as particularly important. However, there is considerably less literature that explicitly discusses them. In this article, I review the literature on diverse coalitions, with a focus on both their theorized and documented importance for social movements and civil resistance campaigns, and the challenges they face (including the factors working against their formation and sustainability). To do so, I bring two closely related but often separate literatures into conversation: social movements and civil resistance. I conclude by evaluating the state of this research area, highlighting remaining gaps, and suggesting directions for future research.
Characterization and validation of an in vivo confocal Raman spectroscopy led tri‐method approach in the evaluation of the lip barrier
Authors: Bielfeldt Stephan , Laing Sabrina , Sadowski Tomasz , Gunt Hemali , Wilhelm Klaus‐Peter
Published: December 2019

Background/Aim

It was the aim to establish and validate in vivo confocal Raman spectroscopy for characterization of the lip barrier in conjunction with transepidermal water loss (TEWL) and skin capacitance assessments. For the first time in vivo, barrier‐relevant components of the lip (derived, natural moisturizing factors (NMFs) and ceramides are described.

Methods

In 32 healthy volunteers, a dental tongue fixation device was inserted to prevent both voluntary and involuntary lip moisturization during measurements. Seventeen individual parameters relating to water, ceramide, and NMF content were assessed via Raman spectroscopy. Additionally, corneometry and TEWL were measured. To give a guidance for the required volunteer group size of future lip barrier studies for all test parameters, coefficients of variation (CV) were calculated and plots showing the required sample size for a given percentage treatment effect.

Results

Raman spectroscopy assessed parameters on the lower lip comprehensively characterized the state of the lip barrier. Parameter variability was sufficiently low to corroborate changes in most parameters using relatively small study populations.

Conclusions

Lip skin is comparatively well hydrated. Biophysical measurement of the lip barrier function is a challenge, as unconscious licking of the lower lip has to be prevented. In vivo confocal Raman spectroscopy provides insightful parameters for the characterization of the lip barrier and sufficiently low inter‐individual variability to assess relatively small parameter changes employing relatively few study subjects. Differences at the molecular level and at a high spatial resolution are detectable, and these insights might provide a breakthrough in the evaluation of lip barrier function and developing solutions for lip care.
The role of lyases, NblA and NblB proteins and bilin chromophore transfer in restructuring the cyanobacterial light‐harvesting complex‡
Authors: Hu Ping‐Ping , Hou Jian‐Yun , Xu Ya‐Li , Niu Nan‐Nan , Zhao Cheng , Lu Lu , Zhou Ming , Scheer Hugo , Zhao Kai‐Hong
Published: December 2019

Phycobilisomes are large light‐harvesting complexes attached to the stromal side of thylakoids in cyanobacteria and red algae. They can be remodeled or degraded in response to changing light and nutritional status. Both the core and the peripheral rods of phycobilisomes contain biliproteins. During biliprotein biosynthesis, open‐chain tetrapyrrole chromophores are attached covalently to the apoproteins by dedicated lyases. Another set of non‐bleaching (Nb) proteins has been implicated in phycobilisome degradation, among them NblA and NblB. We report in vitro experiments with lyases, biliproteins and NblA/B which imply that the situation is more complex than currently discussed: lyases can also detach the chromophores and NblA and NblB can modulate lyase‐catalyzed binding and detachment of chromophores in a complex fashion. We show: (i) NblA and NblB can interfere with chromophorylation as well as chromophore detachment of phycobiliprotein, they are generally inhibitors but in some cases enhance the reaction; (ii) NblA and NblB promote dissociation of whole phycobilisomes, cores and, in particular, allophycocyanin trimers; (iii) while NblA and NblB do not interact with each other, both interact with lyases, apo‐ and holo‐biliproteins; (iv) they promote synergistically the lyase‐catalyzed chromophorylation of the β‐subunit of the major rod component, CPC; and (v) they modulate lyase‐catalyzed and lyase‐independent chromophore transfers among biliproteins, with the core protein, ApcF, the rod protein, CpcA, and sensory biliproteins (phytochromes, cyanobacteriochromes) acting as potential traps. The results indicate that NblA/B can cooperate with lyases in remodeling the phycobilisomes to balance the metabolic requirements of acclimating their light‐harvesting capacity without straining the overall metabolic economy of the cell.
Endophytic fungi in the invasive weed Impatiens glandulifera: a barrier to classical biological control?
Authors: Currie A F , Gange A C , Ab Razak N , Ellison C A , Maczey N , Wood S V
Published: December 2019

The rust fungus, Puccinia komarovii var. glanduliferae, has been introduced into the UK for biological control of the invasive weed, Impatiens glandulifera (Himalayan balsam). However, establishment of the pathogen has differed across the country, which may be partly explained by variation in plant genotype. The aim of this study was to examine whether there is a further layer of phenotypic resistance, provided by indigenous foliar endophytic fungi. Culturable endophytes were isolated from a number of different balsam populations, and the commonest species were inoculated into ‘clean’ balsam plants, to test their interactions with the rust. We found that endophyte communities within balsam are low in diversity and become more dissimilar with increasing distance between populations. Three endophytes (Colletotrichum acutatum, Alternaria alternata and Cladosporium oxysporum) were common and appeared to be antagonistic to the rust, reducing pustule number and mitigating the effect of the pathogen on plant biomass. I. glandulifera thus partially conforms to the endophyte‐enemy release hypothesis, in that as an introduced species, it has an impoverished endophyte complement, acquired from the local environment. However, these endophytes represent a potential barrier to effective biological control and future weed control strategies need to find strains of rust that can overcome plant genetic resistance and the overlaying phenotypic resistance, conferred by endophytes. Future classical biological control programmes of weeds must therefore take into account the fungal bodyguards that invasive species may acquire in their introduced ranges.
Unrecognized diversity of a scale worm, Polyeunoa laevis (Annelida: Polynoidae), that feeds on soft coral
Authors: Bogantes Viktoria E. , Whelan Nathan V. , Webster Katelynn , Mahon Andrew R. , Halanych Kenneth M.
Published: December 2019

A goal of taxonomy is to employ a method of classification based on phylogeny that captures the morphological and genetic diversity of organismal lineages. However, morphological and genetic diversity may not always be concordant, leading to challenges in systematics. The scale worm Polyeunoa laevis has been hypothesized to represent a species complex based on morphology, although there is little knowledge of its genetic diversity. Commonly found in Antarctic waters and usually associated with gorgonian corals (especially Thouarella), this taxon is also reported from the south‐west Atlantic, Magellanic and sub‐Antarctic regions. We employ an integrative taxonomic approach to examine the traditional morphological characters used for scale worm identification in combination with COI mitochondrial gene data and whole mtDNA genomes. Moreover, we consider P. laevis's association with Thouarella by examining data from the mMutS gene, a soft‐coral phylogenetic marker. Analyses for P. laevis recovered 3 clades, two in Antarctic waters and one from the Argentina‐Indian Ocean. Interestingly, genetic and morphological results show differences between specimens from South Argentina and the Antarctic region, suggesting that open ocean barriers might have limited gene flow from these regions. Bayesian phylogenetic analyses for Thouarella resulted in at least 12 lineages, although some of the lineages consist of only a single individual. Our results show different evolutionary histories for both species, confirming that association between these scale worms and their hosts is not restrictive. For both taxonomic groups, biodiversity in the Southern Ocean appears to be underestimated.
Too strict or too loose? Integrative taxonomic assessment of Bombus lapidarius complex (Hymenoptera: Apidae)
Authors: Lecocq Thomas , Biella Paolo , Martinet Baptiste , Rasmont Pierre
Published: December 2019

The latest progress of the taxonomy is the use of integrative approach for species delimitation based on a multisource dataset. However, the taxonomic decision that should be made when convergence between the different lines of evidence is not observed remains debated. Here, we investigate the consequences of the application of an ‘integration by cumulation’ approach on the taxonomic statuses within the Bombus lapidarius complex when using an integrative taxonomic framework (i.e. nuclear and mitochondrial markers along with reproductive traits) compared with a strict ‘integration by congruence’ method. Our results show similar taxonomic conclusions whatever the decision‐making approach used except for one taxon. According to the differentiation observed in our integrative taxonomic framework, recent divergence time and other field observations for this taxon, we assume that a too strict decision‐making method could fail to detect recently diverged species. This is exemplified by the new species Bombus bisiculus sp. n. occurring in South Italy and Sicily.
Measurement of Environmental Stress Cracking Resistance of Polyethylene Pipe: A Review
Authors: Zhang Yi , Jar P.-Y. Ben , Xue Shifeng , Han Limei , Li Lin
Published: December 2019

Use of polyethylene (PE) for water and natural gas transportation has increased rapidly due to its good physical and mechanical properties, especially its excellent corrosion resistance property. However, when immersed in adverse environment and subjected to applied stress, PE will suffer from accelerated crack growth in a phenomenon known as environmental stress cracking (ESC). ESC occurs in a brittle manner without little pre-fracture deformation, thus can cause catastrophic, unexpected failure for PE pipe. A number of different test methods have been developed for characterizing ESC resistance (ESCR) of PE materials. Within this paper, a state-of-the-art review is given on the current ESCR characterization methods, including the working principle and limitations of each method.
The Role of Emulsified Water in the Wax Deposition Path of a Waxy Crude Oil Multiphase Transportation Pipeline
Authors: Lin Xinyu , Wang Zhihua , Feng Qingshan , Zhang Lei , Xu Yunfei
Published: December 2019

Although the problem of wax deposition in multiphase transportation pipelines have been addressed and some related wax deposition models have been developed in recent years, the complex wax deposition paths derived from the potential variety of flow regimes in multiphase flow have not been well understood. This study presented a method for characterizing wax crystals aggregation behavior and developed a model for describing wax deposition path in oil/water two-phase flows. The impact of the emulsified water droplets on wax crystals aggregation in shearing flows was quantified using polarized light microscopy and image analysis method. The role of the emulsified water droplets in the wax deposition path reaching the upper side and lower side of pipeline wall was discussed by solving the developed model which involves the possible inclination angle of multiphase transportation pipeline. The availability of the mechanistic model was validated by the data and knowledge in the existing literature. The results indicated that wax crystals morphologies and structures tended to be regular with the enhancement of shearing effect, and their aggregation behavior were restrained. The circular degree and particle size of wax crystals showed a characteristic that it firstly increased and then decreased with the accumulation of emulsified water droplets in shearing flow, and this transition appeared to the phase inversion point of the oil/water two-phase. The velocity for wax crystals depositing to pipeline wall decreased and the time for wax crystals depositing to pipeline wall extended with the existence of emulsified water droplets. The wax deposition path became more complex in multiphase transportation, and such effect became remarkable when the dispersity of oil/water two-phase enhanced. Accordingly, the intractable wax deposition of waxy crude oil in cold environment transportation would be mitigated to some extent. This study contributes to comprehending the distinction of wax deposition mechanism in single-phase and multiphase transportation of waxy crude oil, and the proposed method and model are valuable for further predicting wax deposition in waxy crude oil emulsions pipelines. The findings in this study also point out an approach to conducting cost-effective flow assurance operations in crude oil production and transportation.
A Novel Method for Gas-Liquid Flow Pattern Recognition Based on PDF and SVM
Authors: Wang Dong-Xu , Hu Qi-Hui , Li Yu-Xing , Wang Quan , Li Shuang
Published: December 2019

Currently, most of the traditional flow pattern recognition methods are based on the features of differential pressure signal, and the verification data is majorly derived from the horizontal or almost horizontal pipes. This paper proposes a new method that combines the probability density function (PDF) of the liquid holdup signal and the support vector machine (SVM). Results demonstrate the capability of the proposed algorithm to effectively recognize the stratified flow, bubble flow, slug flow, and severe slug flow and eliminate subjective factors.
Modelling and Reducing Fuel Flow Pulsation of a Fuel-Metering System by Improving Response of the Pressure Control Valve During Pump Mode Switching in a Turbofan Engine
Authors: Masuda Seiei , Shimizu Fumio , Fuchiwaki Masaki , Tanaka Kazuhiro
Published: December 2019

In an aircraft turbofan engine, a fuel metering unit meters and supplies the required fuel to the engine according to the flight situation. When a centrifugal fuel pump (CFP) is used as the fuel pump, the ratio of hydraulic power per weight can be increased by raising the rated rotational speed, so the weight of the fuel pump can be decreased compared to when using a gear pump (GFP). There is an advantage that it can be reduced significantly. However, since the operating range of the fuel pump is wide, it is not effective to use CFP in an extremely low flow rate region because the fuel temperature rises due to its PQ characteristics and a large loss. Therefore, it is considered effective to combine CFP and GFP as pressure sources, and to use GFP in the low flow region and CFP in the high flow region. For that purpose, it is necessary to have a pump mode switching mechanism. The disadvantage in this case is that changing the pump mode causes a large pressure change of the fuel pressure source, which in turn causes fuel flow pulsations. There are three possible ways to solve this problem. The first method is to keep the differential pressure control valve (DPCV) unit response constant, which keeps the metering valve differential pressure constant in FMS. A second method is to remove high frequency components that the DPCV cannot follow pressure changes in the fuel control system. A third method is to keep the pressure difference between the two fuel sources small and to reduce the amplitude of the applied disturbance. In this paper, the first method, which makes DPCV response high response, is verified by modeling and simulation, and its effectiveness is confirmed.
A Numerical Method for the Analysis of the Theoretical Flow in Crescent-Type Internal Gear Machines With Involute Teeth Profile
Authors: Pan Dinghao , Vacca Andrea
Published: December 2019

Lumped parameter approaches for the description of the flow displaced by hydrostatic pumps and motors have proven to be very effective for both analysis and design purposes. However, while these methods are relatively easy to implement for most of the existing design architectures for positive displacement machines, the case of a crescent-type internal gear machine (CIGM) presents clear challenges as it pertains to the definition of lumped control volumes within the machine. This paper proposes an original scheme for defining lumped control volumes within a CIGM with involute teeth profiles, which is suitable for developing fluid dynamic simulation models for CIGMs. The proposed method strictly obeys fundamental rules on continuous volumes required by lumped parameters models. This is achieved by defining not only multiple control volumes for each displacement chamber but also two variable porting volumes to respect the volume conservation. To prove the validity of the proposed numerical method, the paper provides comparisons between the displaced volume found by the proposed lumped parameter approach and the theoretical kinematic flow ripple provided by an analytical formula available from literature. The results show how the method can be used as a design tool for CIGMs, and particularly to further develop lumped parameter simulation models for detailed fluid dynamic analysis of CIGMs.
A Ceramic Flat Slide Valve for Hydraulic Applications
Authors: Aengenheister Stefan , Liu Chao , Broeckmann Christoph , Schmitz Katharina
Published: December 2019

With a flat slide valve concept, a reduction in leakage and an increase in service life could be achieved compared to conventional piston spool valves. In order to achieve a reduction in leakage flows and guarantee the adjustability of the valves at the same time, a correct design of the pressure compensation is essential. The level of force depends on the operating point of the valve and the position of the slider. Due to the design of the flat slide valve, it is possible to use ceramic semi-finished products for the main stage, which consists of control plates and a slide plate. The geometries are simple enough to be inexpensively manufactured with sufficient accuracy from a ceramic pre-product using laser cutting technology.

High-tech ceramics are a promising material, which can contribute to an improvement of the performance of the valves. The higher resistance of ceramic materials to abrasive wear further increases the service life of the valves. Furthermore, ceramic materials show lower friction coefficients compared to metallic materials, which is of great importance for the concept of the flat slide valve due to the sliding of the plates on top of each other. However, at the same time the use of ceramics, which are rarely used in hydraulics at the moment, means that the design must be appropriate to the material and must be taken into account when designing the main valve stage. This article presents the concept of the flat slide valve for a proportional 4/3-way valve. Therefore, the design of the pressure compensation is shown and the current design of the main valve stage is presented. This includes the design of the flow channels, which has to be suitable for ceramic materials. The preliminary design of the flow channels were executed with CFD-simulations. With the shown design the function of a 4/3-way valve, known from piston spool valves, can be implemented with a linear behavior between slide plate deflection and opening cross section.
On the Energy Efficiency of Dual Prime Mover Pump-Controlled Hydraulic Cylinders
Authors: Gøytil Petter H. , Padovani Damiano , Hansen Michael R.
Published: December 2019

This paper concerns the energy efficiency of a special class of pump-controlled hydraulic cylinders utilizing two prime movers. The performance of such circuits has been studied previously motivated by their capability of providing an actuator stiffness similar to that of servo valve-controlled systems. This characteristic may improve performance and robustness in applications requiring feedback control. In this paper, the presence of losses similar to that of fluid throttling, in the sense that they occur even in the absence of component inefficiencies, are demonstrated for such circuits and shown to degrade the overall energy efficiency of the system. The conditions under which such losses occur are derived analytically as a function of system parameters and operating conditions and two solutions for their elimination are proposed and verified analytically and numerically. Several implementation options are compared in terms of energy efficiency and component sizing and benchmarked to a conventional servo valve solution. It is shown that with the appropriate implementation, an energy efficiency up to ten times greater than that of a conventional servo valve system may be expected.
Model-Based Control of a Pressure-Compensated Directional Valve With Significant Dead-Zone
Authors: Lampinen Santeri , Koivumäki Janne , Mattila Jouni , Niemi Jouni
Published: December 2019

Hydraulic systems on mobile manipulators and industrial systems often come equipped with pressure-compensated proportional directional control valves with significant dead-zone. These kind of hydraulic valves are well suited for open-loop applications with an operator in control. However, designing closed-loop control for such systems is a challenging task. In this study, we propose a model-based control method for such valves to increase the performance of the current state-of-the-art in industrial robotic manipulator control. The proposed control method rigorously addresses the dynamics of a hydraulic manipulator system with dead-zone compensation for pressure-compensated directional control valves. The proposed method is evaluated with experiments on a commercial heavy-duty breaker boom with Sauer-Danfoss PVG 120 valves. The experimental results show accurate control of the manipulator despite the used slow-response load sensing valves.
Automated Design and Analysis of a Variable Displacement Linkage Motor
Authors: Fulbright Nathaniel J. , Boyce-Erickson Grey C. , Chase Thomas R. , Li Perry Y. , Van de Ven James D.
Published: December 2019

Hydrostatic drives consisting of a variable displacement pump and a low speed high torque (LSHT) motor are frequently used in off-highway vehicles. A variable displacement traction motor is desirable because of the ability to downsize the pump and thereby run the hydrostat at higher efficiency, as well as the possibility of hybridization of the drivetrain. Currently on the market are fixed and discrete speed LSHT radial piston motors and high speed low torque variable displacement axial piston motors. The radial piston motors are displacement dense but are not continuously variable, whereas the axial piston motors are continuously variable but require gearboxes, introducing packaging and robustness concerns. The Variable Displacement Linkage Motor (VDLM) is a LSHT motor that is continuously variable. It offers several benefits over current LSHT motors in that it is highly efficient over its operating range, it has low torque ripple, and it is displacement dense due to its multi-lobed cam and radial packaging. As with the design of any motor, the process is iterative and must be performed whenever performance objectives change. This paper describes an automated method for rapid exploration of the solution space for a variable displacement motor with specific application to the VDLM. This method leads to a motor design that theoretically can achieve 97% efficiency with a torque ripple below 5% at full displacement.
Optimization of a Snap Through Spring for a Hydraulic Valve With Hysteresis Response Behavior
Authors: Scherrer Matthias , Scheidl Rudolf , Manhartsgruber Bernhard
Published: December 2019

The hydraulic binary counter requires switching valves with a hysteretic response. In this paper an elastic snap through element is studied as means for that. The concept is based on a buckling beam which is elastically supported in axial direction in order to adjust its buckling properties with moderate manufacturing precision and to assure a well defined snap through behavior. The elastic support is provided by a cantilever beam. A rigorous optimization is performed heading for a most compact and fatigue durable design which exhibits the required lateral force displacement characteristics. A genetic algorithm is used to find the global design optimum. The stress/displacement properties of each design variant are computed by a compact model of the snap through system. It is derived by a Ritz method to obtain approximate solutions of the nonlinear buckling beam behavior. Its validity is checked by a Finite Element model. A compact design is possible if high strength spring steel is used for the elastic elements.
Analysis of Power Distribution in the Hydraulic Remote System of Agricultural Tractors Through Modelling and Simulations
Authors: Tian Xin , Gomez Josias Cruz , Vacca Andrea , Fiorati Stefano , Pintore Francesco
Published: December 2019

Agricultural tractors make massive use of hydraulic control technology. Being fuel consumption a big concern for agricultural applications, tractors typically use the latest state-of-the-art technology to allow efficient fluid power actuation. Nevertheless, the quantification of the energy loss within the hydraulic system of such applications represents an important step to drive the development of the current technology with cost-effective solutions.

In this paper, the load sensing (LS) circuit that typically equips of the hydraulic remotes is taken as reference. A simulation model has been developed within the Amesim software with the aim of accurately predict the operation of the system including the energy flow from the hydraulic supply to the hydraulic user. The paper particularly details the models of the LS pump and the hydraulic remote valves. Within the research, experimental tests on a reference tractor were designed and executed to allow the model validation. The comparison between the experimental results and the simulation data shows the validity of the model. Furthermore, the model allows highlighting the energy losses in the different components of the system as well as identifying the most favorable operating conditions of the system with respect to energy efficiency. The model can be used in support of future research aimed at formulating a more efficient solution for the hydraulic circuit of agricultural tractors.
Mass Estimation of Self-Contained Linear Electro-Hydraulic Actuators and Evaluation of the Influence on Payload Capacity of a Knuckle Boom Crane
Authors: Ketelsen Søren , Andersen Torben Ole , Ebbesen Morten Kjeld , Schmidt Lasse
Published: December 2019

Self-contained linear hydraulic drives are characterized by having integrated the hydraulic power unit e.g. electrical prime mover, hydraulic pumps etc. and the hydraulic cylinder in a single compact unit. Compared to the hydraulic cylinder itself, the mass of the self-contained linear actuator is significantly larger. For some applications, e.g. crane manipulators the additional mass of the actuators compared to conventional valve-controlled hydraulics, may reduce the payload capacity, which is a central performance parameter. As a case study, a medium sized two link knuckle boom crane is modelled and by assuming the force capability of the hydraulic cylinders to be the limiting factor, the reduction in payload capacity is examined if replacing the knuckle boom cylinder with a self-contained hydraulic cylinder drive. By focusing on seven different hydraulic circuit architectures, this study estimates the mass of compact pump-controlled actuators and investigates to what extent the choice of system topology affects the mass of the actuator, and thus payload capacity of the crane. The results show that the choice of hydraulic circuit architecture may affect both the required amount of installed power and the mass of the self-contained actuator. For the considered knuckle boom crane the estimated mass of the needed 59 kW self-contained actuator ranges from 2300 kg to 2521 kg depending on the hydraulic circuit architecture. The mass of the hydraulic cylinder itself used for conventional valve actuation is estimated to 1674 kg. If the entire working range is considered, installing the heavier self-contained actuator reduces the payload capacity with up to 3 % compared to conventional valve actuation.
Fluid Effects on Mechanical Efficiency of Hydraulic Pumps: Dynamometer Measurements and Molecular Simulations
Authors: Panwar Pawan , Len Michelle , Gajghate Ninaad , Michael Paul , Martini Ashlie
Published: December 2019

The mechanical efficiency of hydraulic pumps is affected by the viscosity of the hydraulic fluid. Viscosity modifiers that thicken the fluid, therefore, play an important role in efficiency. Viscosity modifiers are believed to improve the mechanical efficiency of hydraulic systems partially by enabling formulation with lower molecular weight base oils. Here, this concept was directly tested in a pump dynamometer using mixtures of low traction synthetic poly(alphaolefin) base oils, bis(2-ethylhexyl) adipate ester, and poly(isobutylene). Lower viscosity fluids directly correlated to better mechanical efficiency but decreasing the viscosity of the synthetic base oil by adding viscosity modifier did not have the same effect. However, molecular dynamics simulations showed that solution viscosity was directly correlated to elongation of the polymer under shear which, together with calculations of the critical shear rate range in a pump, suggested ways of designing viscosity modifiers to achieve a specific viscosity profile that maximizes mechanical efficiency.
A Buford Complex in a Division I Collegiate American Football Player
Authors: Wiese Brian W. , Miller Kevin , Godoy Eduardo
Published: December 2019

A 19-year-old African-American male Division I collegiate American football player with no prior history of shoulder injury presented with right shoulder pain after making a tackle during a game. He was initially diagnosed with a rotator cuff strain with potential underlying labral pathology. Subsequent magnetic resonance imaging arthrogram showed no labral tearing, though a Buford complex was identified. A Buford complex is a normal anatomical labral variant where the anterior labrum is absent and the middle glenohumeral ligament is “cord-like” in structure. This case was managed conservatively since surgical intervention is only recommended if there is a secondary pathology to the shoulder (e.g., type II superior labrum anterior to posterior [SLAP] lesions). Clinicians should be aware of Buford complexes because they can predispose athletes to secondary injuries and can be managed successfully with a conservative rehabilitation approach in the absence of secondary pathology.
The Effect of Pre–Post Differences in Walking, Health, and Weight on Retirees’ Long-Term Quality of Life
Authors: Deka Devajyoti
Published: December 2019

This research examined the effect of pre–post differences in walking duration, health, and weight on retirees’ long-term quality of life (QoL). It used data from a 2018 randomized mail survey of 483 suburban New Jersey retirees. Ordinary least squares and three-stage least squares models were used. The analysis showed that changes in walking duration during the first 2 years of retirement are directly associated with health change, health change has an effect on long-term QoL, and weight variation of 10 lb or more has an effect on health change and long-term QoL. Although QoL peaks for the sample of retirees at around age 75, people whose average walking duration increased, health improved, and weight did not increase substantially after retirement continued to experience high QoL for a longer time. The results show that people can achieve high long-term QoL by choosing an active lifestyle when transitioning to retirement.
In Vitro
Activity and Microbiological Efficacy of Gepotidacin from a Phase 2, Randomized, Multicenter, Dose-Ranging Study in Patients with Acute Bacterial Skin and Skin Structure Infections
Authors: Scangarella-Oman Nicole E. , Ingraham Karen A. , Tiffany Courtney A. , Tomsho Lynn , Van Horn Stephanie F. , Mayhew David N. , Perry Caroline R. , Ashton Theresa C. , Dumont Etienne F. , Huang Jianzhong , Brown James R. , Miller Linda A.
Published: December 2019

A phase 2 study of gepotidacin demonstrated the safety and efficacy of 3 gepotidacin doses (750 mg every 12 h [q12h], 1,000 mg q12h, and 1,000 mg every 8 h [q8h]) in hospitalized patients with suspected/confirmed Gram-positive acute bacterial skin and skin structure infections (ABSSSIs). Evaluating microbiology outcomes and responses were secondary endpoints.
Methicillin-Resistant Staphylococcus aureus Strains in Swiss Pigs and Their Relation to Isolates from Farmers and Veterinarians
Authors: Kittl Sonja , Brodard Isabelle , Heim Dagmar , Andina-Pfister Patrizia , Overesch Gudrun
Published: December 2019

MRSA is an important human pathogen; thus, its increasing prevalence in livestock over the last decade has a potentially large impact on public health. Farmers and veterinarians are especially at risk due to their close contact with animals. Our work demonstrates a dramatic increase in MRSA prevalence in Swiss pigs, from 2% in 2009 to 44% in 2017. Whole-genome sequencing allowed us to show a close association between farmer and pig strains as well as veterinarian and horse strains, indicating that the respective animals are a likely source of human colonization. Furthermore, we could demonstrate that pig
spa
t011 strains cluster separately and are probably less likely to colonize humans than are pig
spa
t034 strains. This research may provide a basis for a more substantiated risk assessment and preventive measures.
Targeting Kaposi's Sarcoma-Associated Herpesvirus ORF21 Tyrosine Kinase and Viral Lytic Reactivation by Tyrosine Kinase Inhibitors Approved for Clinical Use
Authors: Beauclair Guillaume , Naimo Eleonora , Dubich Tatyana , Rückert Jessica , Koch Sandra , Dhingra Akshay , Wirth Dagmar , Schulz Thomas F.
Published: December 2019

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the cause of three human malignancies: Kaposi’s sarcoma, primary effusion lymphoma, and the plasma cell variant of multicentric Castleman disease. Previous research has shown that several cellular tyrosine kinases play crucial roles during several steps in the virus replication cycle.
Molecular Detection of Biological Agents in the Field: Then and Now
Authors: Yeh Kenneth B. , Wood Hillary , Scullion Matt , Russell Joseph A. , Parker Kyle , Gnade Bryan T. , Jones Anthony R. , Whittier Christopher , Mereish Kay
Published: December 2019

Molecular detection of biological agents in the field has traditionally relied on the use of quantitative real-time PCR (qPCR), which now includes commercially available instruments that can be used in the laboratory or field. Adapting this technology for field-forward applications necessitated innovation to minimize size, weight, and power requirements.
A Targetron-Recombinase System for Large-Scale Genome Engineering of Clostridia
Authors: Cerisy Tristan , Rostain William , Chhun Audam , Boutard Magali , Salanoubat Marcel , Tolonen Andrew C.
Published: December 2019

Clostridia are anaerobic bacteria with important roles in intestinal and soil microbiomes. The inability to experimentally modify the genomes of clostridia has limited their study and application in biotechnology. Here, we developed a targetron-recombinase system to efficiently make large targeted genomic deletions and insertions using the model
Clostridium phytofermentans
. We applied this approach to reveal the importance of a prophage to host fitness and introduce an inducible reporter by recombination-mediated cassette exchange.
Strongyloides, HTLV-1 and small bowel obstruction
Authors: Martyn Emily , Gration Betty , Subbiah Somasundaram Chitra , Chiodini Peter L
Published: December 2019

An 81-year-old Jamaican man who has been resident in the UK for many years presented with one week history of generalised abdominal pain, postprandial vomiting, anorexia, weight loss and abdominal distension. He was managed conservatively for acute small bowel obstruction. Investigations revealed a duodenal stricture. LiveStrongyloides stercoralislarvae were observed in stool samples and duodenal biopsy confirmed the presence of the parasite at multiple life cycle stages within the lamina propria. He was diagnosed withStrongyloideshyperinfection with underlying human T-cell lymphotropic virus type 1 and treated with a prolonged course of ivermectin with ongoing monitoring for relapse. This case demonstrates a rare but potentially fatal cause of small bowel obstruction.
Anticoagulation-induced unilateral adrenal haemorrhage and pseudoaneurysm
Authors: Seow Yi Th'ng , Ng Zi Qin , Wong Sze Ling
Published: December 2019

Spontaneous unilateral adrenal haemorrhage (AH) is extremely rare. Its presentation is usually non-specific and requires a high degree of suspicion as it is associated with high morbidity and mortality if diagnosis is delayed. Hereby, we present a case of 67-year-old man with significant cardiac history presented with right-sided chest pain and non-specific abdominal pain. He was previously treated for non-ST elevation myocardial infarction 5 days ago prior to the current presentation. CT scan of abdomen and pelvis demonstrated a right-sided active AH. The patient subsequently underwent digital subtraction angiography. Angio-embolisation was attempted for the pseudoaneurysm but failed due to spasm of the vessel. He was managed conservatively and discharged after clinical improvement. Clinic review 6 months later showed significant size reduction of the pseudoaneurysm.
Clinical and economic outcomes among injection-naïve patients with type 2 diabetes initiating dulaglutide compared with basal insulin in a US real-world setting: the DISPEL Study
Authors: Mody Reema , Huang Qing , Yu Maria , Patel Hiren , Zhang Xian , Wang Liya , Grabner Michael
Published: December 2019

Aims

To report 1-year clinical and economic outcomes from the retrospective DISPEL (Dulaglutide vs Basal InSulin in Injection Naïve Patients with Type 2 Diabetes: Effectiveness in ReaL World) Study.

Materials and methods

This observational claims study included patients with type 2 diabetes (T2D) and ≥1 claim for dulaglutide or basal insulin between November 2014 and April 2017 (index date=earliest fill date). Propensity score matching was used to address treatment selection bias. Change from baseline in hemoglobin A1c (HbA1c) was compared between the matched cohorts using analysis of covariance; diabetes-related costs were analyzed using generalized linear models.

Results

Matched cohorts (903 pairs total; 523 pairs with complete cost data) were balanced in baseline characteristics with mean HbA1c 8.6%, mean age 54 years. At 1 year postindex, dulaglutide patients had significantly greater reduction in HbA1c than basal insulin (−1.12% vs −0.51%, p<0.01), lower medical costs ($3753 vs $7604, p<0.01), higher pharmacy costs ($9809 vs $6175, p<0.01), and similar total costs ($13 562 vs $13 779, p=0.76). Medical and total costs per 1% HbA1c reduction were lower for dulaglutide than basal insulin (medical: $3128 vs $12 673, p<0.01; total: $11 302 vs $22 965, p<0.01), while pharmacy costs per 1% HbA1c reduction were lower without reaching statistical significance ($8174 vs $10 292, p=0.15).

Conclusions

In this real-world study, patients with T2D initiating dulaglutide demonstrated greater HbA1c reduction compared with those initiating basal insulin. Although total diabetes-related costs were similar, the total diabetes-related costs per HbA1c reduction were lower for dulaglutide, highlighting the importance of evaluating effectiveness along with the economic impact of medications.
Social networks, social capital and end-of-life care for people with dementia: a realist review
Authors: Sawyer Joseph M , Sallnow Libby , Kupeli Nuriye , Stone Patrick , Sampson Elizabeth L
Published: December 2019

Objectives

(1) To develop an understanding of how social capital may be conceptualised within the context of end-of-life care and how it can influence outcomes for people with dementia and their families with specific reference to the context and mechanisms that explain observed outcomes. (2) To produce guidance for healthcare systems and researchers to better structure and design a public health approach to end-of-life care for people with dementia.

Design

A realist review.

Data sources

MEDLINE, EMBASE, CINAHL and grey literature.

Analysis

We conceptualised social capital as a complex intervention and, in order to understand how change is generated, used realist evaluation methods to create different configurations of context, mechanism and outcomes. We conducted an iterative search focusing on social capital, social networks and end-of-life care in dementia. All study designs and outcomes were screened and analysed to elicit explanations for a range of outcomes identified. Explanations were consolidated into an overarching programme theory that drew on substantive theory from the social sciences and a public health approach to palliative care.

Results

We identified 118 articles from 16 countries ranging from 1992 to 2018. A total of 40 context-mechanism-outcome configurations help explain how social capital may influence end-of-life care for people with dementia. Such influence was identified within five key areas. These included: (1) socially orientating a person with dementia following diagnosis; (2) transitions in the physical environment of care; (3) how the caregiving experience is viewed by those directly involved with it; (4) transition of a person with dementia into the fourth age; (5) the decision making processes underpinning such processes.

Conclusion

This review contributes to the dispassionate understanding of how complex systems such as community and social capital might be viewed as a tool to improve end-of-life care for people with dementia.

PROSPERO registration number

CRD42018084524.