bluuebunny/crossref_metadata_2025 huggingface dataset:
The Kidney and COVID-19: Pandemic Effects on the Patients
Authors: Sarwar A.S.M. , Jain Divya , Bushra Anika , Razzak Khandaker Sabit Bin , Hossain Mohammad Nabil , Rahman Sabrina
Published: November 2020

COVID-19 pathogens were identified as new coronaviruses by the sequencing of sample lower respiratory tracts from patients affected, which share a sequence of 79.6 percent identified as severe acute respiratory syndrome coronavirus. The virus has spread rapidly worldwide and was reported as a pandemic on 11 March 2020 since its detection in Wuhan, China in December 2019. The principal characteristics of COVID-19 were diffuse alveolar damage and acute respiratory failure, involving other organs. Although co-morbidities such as diabetes and cardiovascular disease have reported as risk factors of COVID-19, there is still no proof of an increased vulnerability to chronic renal disease in patients with chronic kidney disease (CKDs), although there are several studies continuing worldwide. CKD is differentiated by kidney structure abnormalities or functions which last > 3 months and have an impact on patient health. The deaths were not specifically caused by COVID-19, but were considered systemic causes. In HD patients with COVID-19 there were decreased lymphopenia, reduced serum levels of inflammatory receptors and more severe clinical disease than patients with HD CKD. Therefore, additional precautions should be taken in CKD patients to minimize risk of the infection. Doctors can also be carefully watched to identify signs of worsening of the disease in CKD patients with confirmed COVID-19.
Evaluation of the Antioxidant Activity of Some Plants Used in the Management of Erectile Dysfunction by the BWA Community in Mali
Authors: Togola Issiaka , Dembélé Jean , Daou Cheickna , Diarra Nouhoum , Konaré Mamadou A. , Sanogo Rokia
Published: November 2020

The erection has always symbolized strength and virile health. Erectile dysfunction is undoubtedly a concern as old as humanity. Tamarindus indica L., Guiera senegalensis J.F.Gmel and Ximenia americana L. are commonly used in the traditional treatment of erectile dysfunction by the Bwa community in Mali. The aim of this study was to measure the total polyphenols and flavonoids and then to evaluate the antiradical activity of the extracts (aqueous and hydroalcoholic macerated and decocted) of the organs of these species. The study found that for all species, the hydro-alcoholic macerated extract showed the best results. The polyphenol contents have been 36.85±0.21 mgGAE/g; 32.60±0.25 mgGAE/g and 29.79±0.51 mgGAE/g for Ximenia americana, Tamarindus indica and Guiera senegalensis respectively. The flavonoid contents have been 22.03±0.15 mgQE/g; 17.53±0.02 mgQE/g and 8.03±0.03 mgQE/g for Ximenia americana, Tamarindus indica and Guiera senegalensis respectively. The antiradical activity expressed in IC50 is 37.54±0.75 µg/mL; 52.75±0.71 µg/mL and 54.66±1.14 µg/mL for Ximenia americana, Tamarindus indica and Guiera senegalensis respectively. This study revealed that those plants are rich in total polyphenols and show a good antiradical activity. This wealth would justify their traditional use. The biological tests would be necessary to confirm their use in the treatment of erectile dysfunction.

Keywords: Erectile dysfunction, polyphenols, antioxidant activity, Bwatun-Mali.
Ethnobotanical survey on dandelion use in the western region of Algeria
Authors: Bekhaled Imene , Benalia Abdelkrim , Mehida Hayet , Meziani Samira , Tarfaoui Luiza , Djebbar Ahmed Abdelhamid , Demmouche Abassia
Published: November 2020

Introduction: Dandelion (Taraxacum officinale) is an edible and medicinal plant. We use the leaves, flowers and roots. The objective of this study is to show interest in the use of dandelion as a natural remedy in the primary treatment of serval pathologies. Methods : An ethnobotanical survey of 1000 people in the western region of Algeria was conducted using a questionnaire. Results: the obtained results from this study show that 60% of the population questioned prefer traditional medicine the majority of them use the plant in the medical field whose leaves and roots are most used. Infusion and maceration are the most usable methods for the preparation of the plant and administration is exclusively oral. Most users testify that the plant has significant efficacy with a percentage of 61%. Conclusion :All this information constitutes a database to perform other research in vivo or in vitro to value this planton the therapeutic level. Keywords : Taraxacum Officinale, traditional medicine, leaves, ethnobotanical study.
Transmission and Pathogenesis of Coronavirus Disease (COVID-19) Outbreak
Authors: Sawikr Yousef
Published: November 2020

The current pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has presented unmatched challenges to the healthcare systems in almost every country around the world. Currently, there are no established effective vaccines or therapeutic agents against the virus. Present clinical management includes infection prevention and control process and supportive care including supplemental oxygen and mechanical ventilator support. It is proposed this is likely the zoonotic beginning of COVID-19. Individual to-individual transmission of COVID-19 contamination prompted the separation of patients that were accordingly managed an assortment of medicines.

Keywords: COVID-19, SARS-CoV-2, supplemental oxygen, ventilator support
A DFT study of thermal and structural properties of 2D layers (Short title: Two-Dimensional materials)
Authors: Majid Abdul , Kanwal Hajra , Khan Salah , Ahmad Ashfaq
Published: November 2020

Two-dimensional (2D) materials have exhibited exceptional properties
which meet the demands of future applications. These materials appeared
after discovery of graphene in 2004 offered such device grade
characteristics at nanoscale which did not appear on bulk scale. The
research turned to search alternate 2D materials when drawbacks of
graphene became surfaced. Despite significant successes and
unprecedented efforts which consequent upon several beyond-graphene 2D
materials, the complete potentials of such materials are still
unexplored which may restrict their usage in devices. This work was
carried out with motivation to investigate the thermal stability of
several 2D-mono-layered materials including graphene, Borophene,
Aluminene, Germanene, BN, SiC and MoS2 based on classical Molecular
Dynamics Simulations. Prior to the implementation of the conditions for
thermal calculations, the structures were optimized using
Geometry-Optimization method. It appeared that all the structural
parameters which includes lattice-constant, bond-length and dihedral
angles were precisely determined. On the contrary, it was found that
several materials beyond graphene can resist up-to certain temperature
ranges, depicting the material dependent thermal stability. The radial
distribution function (RDF) was calculated which pointed towards thermal
broadening, bond breakage and bond formation for the slabs. The
RDF-peaks were found to characterize the probability of finding any
particle in the nearest neighbors which extend the phenomenon of thermal
stability. Thermal stability was compared by plotting the temperature
and energy curves from which, the phase transition temperature and heat
capacity was determined for the slabs including graphene as benchmark.
The phase transition temperatures are found as 4510 K, 2273 K, 933 K,
1670 K, 3246 K, 4050 K, and 1460 K for graphene, Borophene, Aluminene,
Germanene, BN, SiC and MoS2 respectively. Besides the analysis of
temperature-energy variations, the thermal broadening is also determined
and discussed to examine the thermal-stability for usage of the
materials in high temperature applications.
Immunohistochemical study of solitary fibrous tumor in the ear related to pazopanib use
Authors: Kawano Toshiaki , Hirano Takashi , Fujinaga Maki , Kadowaki Yoshinori , Matsunaga Takayuki , Tateyama Kaori , Kizu Yumi , Suzuki Masashi
Published: November 2020

This is the first report using an anti-tumor drug called Pazopanib for a
case of solitary fibrous tumor that occurred in the ear canal. Pazopanib
will be useful for clinicians involved in this case in the future, we
have reported the detailed progress and immunological analysis.
Are ecological communities the seat of endosymbiont horizontal transfer and diversification? A case study with soil arthropod community.
Authors: Gupta Manisha , Kaur Rajbir , Gupta Ankita , Raychoudhury Rhitoban
Published: November 2020

Maternally inherited endosymbionts are one of the most abundant bacteria
infecting arthropods and show extensive horizontal transfer. Such
widespread distribution and extensive recombination among these
endosymbionts could be an outcome of horizontal transfer as for such
genetic exchanges to occur their hosts should come in contact. One such
level of biological organization where different hosts can do that is
the ecological community. Despite various studies focusing on known
model species and specific ecological interactions among hosts, reports
on community wide endosymbiont data are rare. To better understand
endosymbiont spread, we investigated the incidence, diversity, extent of
horizontal transfer and recombination of three such endosymbionts
(Wolbachia, Cardinium and Arsenophonus) in a specific soil arthropod
community. Wolbachia strain characterization was done using multiple
genes whereas single 16S rRNA gene was used for Cardinium and
Arsenophonus. Amongst 3509 individual host arthropods belonging to 390
morphospecies, 12.05% were infected with Wolbachia, 2.82% with
Cardinium and 2.05% with Arsenophonus. Phylogenetic incongruence
between host and endosymbiont indicated extensive horizontal transfer of
endosymbionts within this community. Three cases of recombination
between Wolbachia supergroups and eight incidences of within supergroup
genetic exchange were also found. Statistical tests of similarity
indicated supergroup A Wolbachia and Cardinium to show a pattern
consistent with rapid horizontal transfer within the community. However
same tests done for super group B Wolbachia and Arsenophonus did not
show similar patterns. We highlight the importance of extensive
community wide studies for a better understanding of the spread of
endosymbionts across global arthropod communities.
Uncovering the genetic diversity of yams (Dioscorea spp.) in China by combining phenotypic trait and molecular marker analyses
Authors: Cao Tianxu , Sun Jingyu , Shan Nan , Chen Xin , Wang Putao , Zhu Qianglong , Zhang Hongyu , Zhou Qinghong , Huang Yingjin
Published: November 2020

China is one of the native places of yams with abundant representative
local varieties. However, the genetic differences between these local
varieties remains unclear, thus considerably inhibiting their
utilization and development. In this study, 26 phenotypic traits of 112
accessions from 21 provinces in China were evaluated, and 24 simple
sequence repeat (SSR) and 29 sequence-related amplified polymorphism
(SRAP) markers were used for the genetic diversity analysis. A total of
56 variations of 20 quality traits were detected in 112 accessions, and
the most diverse phenotypic trait was stem color. Meanwhile, seven
principal components were obtained from 26 phenotypic traits, with a
cumulative contribution rate of 69.39%, and all the accessions were
divided into six groups by clustering the phenotypic traits. Unweighted
pair-group method with arithmetic means and principal coordinate
analysis based on SSR-SRAP marker data showed that 112 accessions were
also divided into six groups, similar to the result of phenotypic traits
but with a slight difference among few accessions. Results of genetic
structure analysis showed that 112 accessions could be divided into two
groups; one group composed of the accessions of D. opposita, the most
abundant resource in China, and the other group was a collection of the
other accessions. In addition, the analysis of the origin and genetic
relationship of yam also indicated that the specie of D. opposita may
have originated in China. These results clarified the genetic
differences in yam in China, thereby providing a basis for the
identification, evaluation, and conservation of yam resource.
Ascending aorta cannulation in totally thoracoscopic minimally invasive cardiac surgery
Authors: Liao Shengjie , Zhang Xiaoshen
Published: November 2020

The Cannulation through the femoral artery is the preferred method of
establishing peripheral extracorporeal circulation in totally
thoracoscopic minimally invasive cardiac surgery (MICS). However, facing
to contraindications of femoral artery cannulation, a modified aortic
cannulation is an alternative approach for totally thoracoscopic MICS.
Larger workers outperform smaller workers across resource environments: an evaluation of demographic data using functional linear models
Authors: Kerr Natalie , Malfi Rosemary , Williams Neal , Crone Elizabeth
Published: November 2020

1. Behavior and organization of social groups is thought to be vital to
the functioning of societies, yet the contributions of various roles
within social groups towards population growth and dynamics have been
difficult to quantify. A common approach to quantifying these role-based
contributions is evaluating the number of individuals conducting certain
roles, which ignores how behavior might scale up to effects at the
population-level. Manipulative experiments are another common approach
to determine population-level effects, but they often ignore potential
feedbacks associated with these various roles. 2. Here, we evaluate the
effects of worker size distribution in bumblebee colonies on worker
production in 24 observational colonies across three environments, using
functional linear models. Functional linear models are an underused
correlative technique that has been used to assess lag effects of
environmental drivers on plant performance. We demonstrate potential
applications of this technique for exploring high-dimensional ecological
systems, such as the contributions of individuals with different traits
to colony dynamics. 3. We found that more larger workers had mostly
positive effects and more smaller workers had negative effects on worker
production. Most of these effects were only detected under low or
fluctuating resource environments suggesting that the advantage of
colonies with larger-bodied workers becomes more apparent under
stressful conditions. 4. We also demonstrate the wider ecological
application of functional linear models. We highlight the advantages and
limitations when considering these models, and how they are a valuable
complement to many of these performance-based and manipulative
experiments.
Prediction model of rhomboid major and pleura depth based on anthropometric features to decrease the risk of pneumothorax during dry needling
Authors: Valera-Calero Juan Antonio , Cendra-Martín Enrique , Fernández-Rodríguez Tomás , Fernández-de-las-Peñas César , Gallego-Sendarrubias Gracia María , Guodemar-Pérez Jesús
Published: November 2020

Background: Although mostly common adverse events associated to dry
needling can be considered minor, serious adverse events including
induced pneumothorax cannot be excluded, and safety instructions for
reducing the risk of pleura puncture are needed. Objective: To
investigate if anthropometric features can predict the rhomboid major
muscle and pleura depth in a sample of healthy subjects to avoid the
risk of pneumothorax during dry needling. Methods: A diagnostic study
was conducted on 59 healthy subjects (52.5 % male) involving a total of
236 measurements (both sides in maximum inspiration and expiration), to
calculate the accuracy of a prediction model for both pleura and
rhomboid depth, as assessed with ultrasound imaging, based on sex, age,
height, weight, body mass index (BMI), breathing and chest
circumference. A correlation matrix and a multiple linear regression
analyses were used to detect those variables contributing significantly
to the variance in both locations. Results: Men showed greater height,
weight, BMI, thorax circumference and skin-to-rhomboid,
rhomboid-to-pleura y skin-to-pleura distances (p<0.001). Sex,
BMI, and thorax circumference explained 51.5% of the variance of the
rhomboid (p<0.001) and 69.7% of pleura (p<0.001)
depth limit. In general, inserting a maximum length of 19 mm is
recommended to reach the deep limit of rhomboid major decreasing the
risk of passing through the pleura. Conclusion: This study identified
that gender, BMI and thorax circumference can predict both rhomboid and
pleura depth, as assessed with ultrasonography, in healthy subjects. Our
findings could assist clinicians in the needle length election for
avoiding the risk of induced pneumothorax during dry needling.
Effect of Layering Techniques on Polymerization Shrinkage Stress of High- and Low-viscosity Bulk-fill Resins
Authors: Tsujimoto A , Jurado CA , Barkmeier WW , Sayed ME , Takamizawa T , Latta MA , Miyazaki M , Garcia-Godoy F
Published: November 2020

Clinical Relevance

The use of layering techniques is still advisable with many bulk-fill resins and should be the default unless a particular resin is known to not need it.

Objective: The purpose of this study was to investigate how layering techniques affect polymerization shrinkage stresses of high-and low-viscosity bulk-fill resins.

Method: Six high-viscosity and six low-viscosity bulk-fill resins were evaluated. Aluminum blocks with a mesial-occlusal-distal (MOD) cavity were machined and randomly divided into groups for different filling techniques (bulk-fill vs horizontal layering vs oblique layering) and further subdivided according to type of resin (high- vs low-viscosity). The cuspal deflection resulting from the polymerization of bulk-fill resin bonded to a MOD cavity within an aluminum block was measured with a digimatic micrometer. Scanning electron microscopy analyses of tested resins were also conducted.

Results: In the high-viscosity bulk-fill resins, cuspal deflection of the MOD cavity ranged from 11.2 to 18.2 μm with the bulk-filling technique, from 10.7 to 15.5 μm with the horizontal layering technique, and from 10.9 to 15.2 μm with the oblique layering technique. In the low-viscosity bulk-fill resins, cuspal deflection of the material ranged from 9.2 to 19.8 μm with the bulk-filling technique, from 8.2 to 15.7 μm with the horizontal layering technique, and from 8.4 to 16.4 μm with the oblique layering technique.

Conclusion: Cuspal deflections for some high-and low-viscosity bulk-fill resins were significantly reduced by using layering techniques, but the resultant improvement of layering techniques was not applicable to all the bulk-fill resins used in this study.
Measurement of Water Film Thickness Due to Sipe Edges of Studless Tires
Authors: Takimi Akihiro , Iwai Tomoaki , Shoukaku Yutaka
Published: November 2020

Water on an icy surface is wiped by the rubber sipe edges of studless tires. However, it has been proposed that water on an icy surface forms a thin film rather than being removed completely. Nonetheless, there have been relatively few studies on the contact conditions of rubber sipe edges and the formation of a water film due to wiping. In this study, the frictional properties and contact areas of model sipes of studless tires were measured. In addition, the thickness of the water film formed on the tread surface was estimated by optical interferometry. Three types of styrene butadiene rubber with different levels of hardness were used as rubber specimens. The experiment was conducted by varying both the number of rubber edges and the slope angle between the rubber specimens and the vertical direction of a glass disk. The coefficient of friction tended to decrease with increasing sliding speed at all slope angles, and the value of the coefficient of friction was decreased as the slope angle became large. Moreover, the contact area between the rubber edges and a glass disk with a slope angle of 0° tended to increase as the sliding speed increased. The thickness of the water film formed after wiping ranged from 0.98 to 1.70 μm, and it increased as the slope angle increased.
An Analytical Thermodynamic Approach to Friction of Rubber on Ice
Authors: Wiese Klaus , Kessel Thiemo M. , Mundl Reinhard , Wies Burkhard
Published: November 2020

The presented investigation is motivated by the need for performance improvement in winter tires, based on the idea of innovative “functional” surfaces. Current tread design features focus on macroscopic length scales. The potential of microscopic surface effects for friction on wintery roads has not been considered extensively yet.

We limit our considerations to length scales for which rubber is rough, in contrast to a perfectly smooth ice surface. Therefore we assume that the only source of frictional forces is the viscosity of a sheared intermediate thin liquid layer of melted ice. Rubber hysteresis and adhesion effects are considered to be negligible.

The height of the liquid layer is driven by an equilibrium between the heat built up by viscous friction, energy consumption for phase transition between ice and water, and heat flow into the cold underlying ice. In addition, the microscopic “squeeze-out” phenomena of melted water resulting from rubber asperities are also taken into consideration. The size and microscopic real contact area of these asperities are derived from roughness parameters of the free rubber surface using Greenwood-Williamson contact theory and compared with the measured real contact area.

The derived one-dimensional differential equation for the height of an averaged liquid layer is solved for stationary sliding by a piecewise analytical approximation. The frictional shear forces are deduced and integrated over the whole macroscopic contact area to result in a global coefficient of friction. The boundary condition at the leading edge of the contact area is prescribed by the height of a “quasi-liquid layer,” which already exists on the “free” ice surface.

It turns out that this approach meets the measured coefficient of friction in the laboratory. More precisely, the calculated dependencies of the friction coefficient on ice temperature, sliding speed, and contact pressure are confirmed by measurements of a simple rubber block sample on artificial ice in the laboratory.
Investigating Applicability of the Meshfree Method to the Structural Analysis of Tires
Authors: Ishihara Ken , Noda Takehiro , Sakurai Hiroyuki
Published: November 2020

In contrast to the finite element method (FEM), which is widely used in the tire industry nowadays, some alternative methods have been proposed by academic communities over the past decade or so. The meshfree method is one of those new methodologies. Originally intended to remove the burden of creating the mesh that is inherent in FEM, the meshfree method relies on the point data rather than the mesh, which makes it much easier to discretize the geometry. In addition to those modeling issues, it has been found that the meshfree method has several advantages over FEM in handling geometrical nonlinearities, continuities, and so forth. In accordance with those emerging possibilities, the authors have been conducting research on the matter. This article describes the results of the authors' preliminary research on the applicability of the meshfree method to tire analyses, which include the theoretical outline, the strategy of tire modeling, numerical results, comparisons with results of FEM, and conclusions.
Interaction of Anti-lock Braking Systems with Tire Torsional Dynamics
Authors: Adcox John , Ayalew Beshah , Rhyne Tim , Cron Steve , Knauff Mike
Published: November 2020

A tire's torsional dynamics couple the responses of wheel/hub inertia to that of the ring/belt inertia. Depending on the effective stiffness, damping, and mass distribution of the tire, the ensuing deflections between the wheel and the ring can cause significant errors in the estimation of the tire's longitudinal slip from wheel speed measurements. However, this remains the established approach for constructing anti-lock braking system (ABS) control algorithms. Under aggressive braking events, the errors introduced by torsional dynamics may significantly affect the ABS algorithm and result in less than optimal braking performance. This article investigates the interaction of tire torsional dynamics and ABS control using a comprehensive system model that incorporates sidewall flexibility, transient and hysteretic tread-ground friction effects, and the dominant dynamics of a hydraulic braking system. It considers a wheel/hub acceleration-based ABS controller that mimics the working steps of a commercial ABS algorithm. Results from multiple sensitivity studies show a strong correlation of stopping distances and ABS control activity with design parameters governing tire/wheel torsional response and the filter cutoff frequency of the wheel acceleration signals used by the controller.
Aluminum Taper Bristle-Shaped Shear Band for a Nonpneumatic Tire
Authors: Berglind Luke A. , Ju Jaehyung , Summers Joshua D.
Published: November 2020

Shear-compliant cellular structures have been considered as replacement elastomeric materials in nonpneumatic tire (NPT) shear band to reduce hysteretic energy loss and rolling resistance. In this article, a rectangular-shaped, aluminum cellular shear band is introduced, which uses a tapered-bristle structure. The tapered-bristle geometry was designed to efficiently use material deformation by evenly distributing stresses throughout the structure under shear deformation. The resulting cellular structures are able to achieve higher shear compliance while maintaining high shear stiffness as required for NPT applications. The objective of this study was to discover how a cellular bristle shear band affects NPT performance when compared with a solid-material shear band with similar effective shear properties. An analytical model was developed to design the tapered-bristle shear band to achieve a target set of effective shear properties, and numerical tests were conducted using Abaqus to validate the analytical model. Full NPT models were created in Abaqus using the tapered-bristle shear band developed in this article and a solid-material shear band with similar effective shear properties. The performances of the two models are compared to determine the effects of a bristle shear band in terms of vertical force–deflection and contact pressure.
Finite Element Modeling for Steel Cord Analysis in Radial Tires
Authors: Yintao Wei , Yiwen Luo , Yiming Miao , Delong Chai , Xijin Feng
Published: November 2020

This article focuses on steel cord deformation and force investigation within heavy-duty radial tires. Typical bending deformation and tension force distributions of steel reinforcement within a truck bus radial (TBR) tire have been obtained, and they provide useful input for the local scale modeling of the steel cord. The three-dimensional carpet plots of the cord force distribution within a TBR tire are presented. The carcass-bending curvature is derived from the deformation of the carcass center line. A high-efficiency modeling approach for layered multistrand cord structures has been developed that uses cord design variables such as lay angle, lay length, and radius of the strand center line as input. Several types of steel cord have been modeled using the developed method as an example. The pure tension for two cords and the combined tension bending under various loading conditions relevant to tire deformation have been simulated by a finite element analysis (FEA). Good agreement has been found between experimental and FEA-determined tension force-displacement curves, and the characteristic structural and plastic deformation phases have been revealed by the FE simulation. Furthermore, some interesting local stress and deformation patterns under combined tension and bending are found that have not been previously reported. In addition, an experimental cord force measurement approach is included in this article.
Accelerometer Measurements of Tire Tread Vibrations and Implications to Wheel-Slap Noise
Authors: Dare Tyler , Bernhard Robert
Published: November 2020

There are many analytical and finite element models for predicting vibration of a tire tread. However, experimental verification of these models is limited because of the difficulties involved in measuring vibration near the contact patch of the tire. In this research, a set of experiments were conducted using a microaccelerometer mounted against the tire tread, in the center of the tread pattern. The tire was mounted on Purdue University's tire-pavement test apparatus, a machine that allows precise measurements of tire noise and vibration as the tire rolls over samples of actual pavement. Microphone and accelerometer signals were recorded to determine the influence of pavement parameters on tire-pavement noise generation mechanisms. The vibration measurement and signal processing techniques are verified by comparing the results to published studies. The relationship between vibration characteristics and noise was investigated as a tire rolls over contraction joints in Portland cement concrete pavements. We found that although travelling waves are generated at the leading and trailing edge of the contact patch, the speed coefficients of increased noise and traveling wave amplitude do not match, and the wave speed of the impulse is that of an inefficient radiator. Therefore, increased tread vibration is not a major cause of increased noise at contraction joints, and other mechanisms must be involved.
Analysis of the Influence of Vehicle Dynamic Parameters on Tire Marks
Authors: Seipel Gunther , Baumann Frank , Hermanutz Ralf , Winner Hermann
Published: November 2020

Tire marks play a central role in the reconstruction of traffic accidents, since they can provide valuable information about the vehicle's trajectory, initial speed, or the steering and braking input of the driver. The research project described in this paper focuses on the analysis of tire marks under controlled conditions using a monowheel setup to enable a selective variation of different vehicle dynamic parameters without mutual influence. The long-term goal is to find a model for the development of tire marks to predict the influence of specific vehicle dynamic parameters on the generation of tire marks. This model may be applied in accident reconstruction tools. A literature review has been performed to find evidence for the development of tire marks and to identify relevant parameters for their generation. Currently, no explicit physical or mathematical model showing the influence of tire forces or slip on the generation of tire marks is available. In the literature, it is often assumed that tire marks occur at the limit of traction. A physically motivated formula has been developed to calculate the friction force within the contact patch as a function of the tire forces, the longitudinal slip, and the side slip angle. The main hypothesis deduced from this formula is that the intensity of a tire mark depends on the magnitude of this friction force independent of the varying parameter. To verify this hypothesis, experiments have been conducted with variations in longitudinal slip, side slip angle, and tire type. First results agree with the model, showing a correlation between the intensity of tire marks and friction force, depending on the tribological and optical tire and road properties. This correlation is introduced as tire-marking sensitivity.
Piezoelectric Vibration-Based Energy Harvesters for Next-Generation Intelligent Tires
Authors: Singh Kanwar Bharat , Taheri Saied
Published: November 2020

Because of access limitations inside the tire, the use of batteries for sensor nodes embedded inside an intelligent tire is not practical. The high vibration levels inside a tire have the potential to generate electrical power using vibration-based energy-harvesting techniques. In this article, the feasibility of using an inertial vibrating energy harvester unit to power a sensor module for tire use is assessed. To predict the electrical power output of the generator, a generic analytical model based on the transfer of energy within the system has been derived. The vibration measurements taken from the test conducted using accelerometers embedded in the tire have been applied as an excitation to the model to predict the power output for a device of suitable dimensions and to study the feasibility of this concept. For the tire applications, a special compact harvester design has been proposed that is able to withstand large shocks and vibrations. Suitable mathematical models for different harvester configurations have been developed to identify the best configuration suited for use inside a tire. The harvester unit demonstrates power generation over a wide speed range and provides a distinct advantage in cost and flexibility of installation while extending the lifetime of the power supply for sensor data acquisition and communication. Results indicate the viability of the procedure outlined in the article.
Modeling of Strain Energy Harvesting in Pneumatic Tires Using Piezoelectric Transducer
Authors: Kubba Ali E. , Behroozi Mohammad , Olatunbosun Oluremi A. , Anthony Carl , Jiang Kyle
Published: November 2020

This paper presents an evaluation study of the feasibility of harvesting energy from rolling tire deformation and using it to supply a tire monitoring device installed within the tire cavity. The developed technique is simulated by using a flexible piezoelectric fiber composite transducer (PFC) adhered onto the tire inner liner acting as the energy harvesting element for tire monitoring systems. The PFC element generates electric charge when strain is applied to it. Tire cyclic deformation, particularly at the contact patch surface due to rolling conditions, can be exploited to harvest energy. Finite element simulations, using Abaqus package, were employed to estimate the available strain energy within the tire structure in order to select the optimum location for the PFC element. Experimental tests were carried out by using an evaluation kit for the energy harvesting element installed within the tire cavity to examine the PFC performance under controlled speed and loading conditions.
Objective Analysis of the Stability of an Extralegal Weight Tractor-Trailer Combination during a Rapid Air Loss Event
Authors: Anderson Jeffery , Pawlowski Ryan
Published: November 2020

In the California Transportation Permits Manual, the minimum overall tire-to-tire axle width (overall width) of a vehicle in the extralegal weight configuration is 2.44 m. Commercial truck tractor and trailer tandem 1.82-m-wide axles fitted with new-generation wide base single (NGWBS) tires measure 2.34 m in overall axle width; thus, they are not compliant with the current California Department of Transportation requirement. Because of the growing application of NGWBS tires in the market, it is important to understand the vehicle stability characteristics of a tractor-semitrailer fitted with both dual and NGWBS tire configurations. In this research, a comparison of dual to NGWBS with both a 50.8-m outset wheel and a 25.4-mm outset wheel is presented. A rapid air loss (RAL) event was initiated to represent a severe scenario in each of the three following maneuvers: straight line, steady-state curve, and lane change. The data were evaluated, and differences between NGWBS and dual tire–fitted vehicles were compared. While a tire RAL event can be perceived as a dramatic event, previous studies and driver-training events have shown that such an RAL event is manageable. The conclusion of this work is that an RAL event with NGWBS tires is as manageable as a dual tire–fitted vehicle and does not make the system unstable.
Experimental Friction and Temperature Investigation on Aircraft Tires
Authors: Linke Tim , Wangenheim Matthias , Lind Hagen , Ripka Stefan
Published: November 2020

For modeling an aircraft tire using the brush model method, the friction coefficient μ between rubber and asphalt should not only be described in terms of the applied pressure and sliding velocity/slip ratio, but also by local temperature inside the contact area. Its influence cannot be neglected, since it leads to significant material property changes. Therefore, investigations on different test rigs are analyzed using thermal recordings of an infrared camera.

First measurements are done on a high speed linear tester (HiLiTe), a test rig at the Institute of Dynamics and Vibration Research (IDS) at Leibniz University Hanover, Germany. It allows testing single tread block samples with a constant slip ratio of 100%, that is, pure sliding, on a variety of surfaces such as dry and wet asphalt or concrete, as well as on snow and ice.

Results in this paper show that the convection has a smaller impact on tread block cooling than the actual contact between runway surface and sample. Since colder surface temperatures lead to higher friction, this effect antagonizes the excitation frequency, which heats up the rubber sample at high velocities. On long-lasting test sequences a quasi–steady-state friction coefficient might be achieved once these effects start to converge. Still, owing to permanent slip, the abrasion leads to cooling as the hot top layer of the rubber is removed occasionally.

In addition to these quasi–steady-state measurements on HiLiTe, the thermal behavior of an aircraft tire is investigated with an autonomously running test rig. It allows realistic testing on an airfield runway by altering load, speed, and slip angle of the tire within and beyond the regions of a passenger aircraft. During the measurements, new and partially unknown effects could be observed. The temperature is mostly influenced by the slip angle followed by speed and load. Furthermore, the contact between tire and runway leads to cooling of the tread but does not affect the temperature inside the grooves. They heat up separately and tend to transfer heat to the tread if the cooling by the runway becomes too low.
Average Worn Profile of Tires in Europe
Authors: Biesse Frédéric , Mahé Jérôme , Lévy Nicolas
Published: November 2020

Tire tread wear is a key issue in the tire development process and for tire customers. In order to measure the wear performance, tire manufacturers usually proceed to wear tests and calculate the tire life from those tests. An important point in this tire life computation is the criteria chosen for defining the tire's end of life. In Europe, there is a legal minimum tread depth set to 1.6 mm applicable to 75% of the tread pattern width. However, outside those 75% (i.e., on the shoulder part), no clear and shared limit is defined. Also, the usual behavior of customers to decide when their tires should be changed is not well known. The goal of this 2012 study was to identify an average worn profile of tires in Europe and the behavior of customers for replacing their tires. For that, 3000 tires worn out by customers have been collected in scrapyards and measured in five European countries. In this article, we will present the tire collecting method, the measurement process, the analysis method, and some general results and statistics on this 3000 tire database. Finally, the method to compute the average end of life profile and the resulting profile is given.
Heavy Truck Driver Workload Investigation
Authors: Pawlowski Ryan
Published: November 2020

Driver workload is of growing interest in the automotive society, since the number of in-vehicle technologies and vehicles on the road grows. Operational and environmental factors impact the driver's ability to negotiate a chosen course and place heavy demands on the driver in terms of mental and physical capacity. A key component of the driver's operating environment is the vehicle. In this research, the impact of various tire configurations, for example, dual and wide based, for a Class 8 tractor–semitrailer combination vehicle on driver workload performance is presented. Driver workload performance is assessed during four maneuvers: 60 m radius steady state circle, 120 m radius steady state circle, road course, and North Atlantic Treaty Organization emergency lane change maneuver. Surface electromyography (sEMG) electrodes were placed on the left and right wrist flexors (flexor carpi ulnaris) and right wrist extensors (extensor carpi ulnaris) in order to capture muscle activity during all maneuvers. Peak and integrated values of sEMG are calculated to obtain metrics of driver workload. Results of the study show distinct separation of muscle activity for each tire configuration. Differences in driving techniques were also identified based on the dominant hand of the driver and orientation of the maneuver, that is, clockwise or counterclockwise.
Tire Operational and Sustainability Trade-Offs
Authors: Pottinger Marion G.
Published: November 2020

In 2012 the Sustainable Worldwide Transportation Consortium at the University of Michigan Transportation Research Institute (UMTRI) funded a forecast of likely changes in tire sustainability through 2025, as a result of feasible tire evolution. This paper is a synopsis of the resulting report, “Tire Operational and Sustainability Tradeoffs” [Reference 5], completed in late summer 2013. In it results are expressed in terms of fuel amount, distance, and weight commonly used in the United States rather than in SI units or in terms used in the underlying mandated goals such as grams of CO2 per mile (light vehicles) or grams per load-ton per 100 miles (medium and heavy vehicles) because of the underlying regulatory framework (Unit conversions to SI are found in the Appendix). The forecast fuel-economy change is the primary factor considered in evaluating tire sustainability. The secondary factor considered is the change in raw material usage, which affects tire weight. The changes are predicted for the five vehicle power plants now in use: gasoline, diesel, hybrid, plug-in hybrid, and battery electric. Vehicles from class A to class E plus pickup trucks are analyzed. This is done with consideration of expected changes in vehicle weight. Tire sizes that are likely to be used, as the vehicles change, are estimated. It is possible that operational trade-offs may preclude tire changes that are desirable in terms of sustainability. To this end, probable vehicle ride and handling effects along the different possible tire-evolution paths are assessed. Aspects of ride that are considered are harshness, modal frequencies, and in-vehicle noise. Cornering in the ordinary driving range, stopping, and the limits of cornering are examined as aspects of handling. Effects on dry, wet, and snowy surfaces are considered. The conclusion reached is that the best tire technical path to follow from now until 2025 is to use higher-aspect-ratio tires operating at higher cold-inflation pressures, provided that any negatives in ride and handling can be overcome in vehicle design. Styling questions are not considered in the report, but it is noted that these could be an important problem, since the tires on the technically desirable path will not have the appearance to which customers have been accustomed in recent years.
Development and Performance Evaluation of Groundnut Digger Elevator cum Heap Formater
Authors: Yadav Rajvir
Published: November 2020

Groundnut (Archis hypogaea L) or peanut is a major oilseed crop which contributes 40 per cent of the total area and 30 per cent of total production of oilseed crops. In India among the major groundnut growing states, Gujarat is the most important one accounting for 36 % of the total area. The groundnut digger elevator cum heap formater was developed considering various theories related to digger, elevator and heap formater assembly, agronomical parameters of groundnut, functional requirement and general consideration. The main components such as main frame, digging blade, elevator and heap assembly were developed. The developed groundnut digger elevator cum heap formater was able to dig up the groundnut plants with pods and convey them for removing the soil from pods and making heap. The experimental results showed the depth of cut of groundnut digger elevator cum heap assembly was found as 13.00 cm, while width of coverage measure as 60 cm and moisture content (d.b.) of 19.20%. The draft requirement of 235 kgf and power requirement was calculated 7.83 hp with fuel requirement of 2.04 l/h. The theoretical field capacity of digger elevator cum heap formater was 0.12 ha/h while effective field capacity was 0.0935 ha/h with field efficiency of 80.47 %. The digging efficiency were found as 84.18, 85.23 and 86.36 % at the forward speed of 1.5, 2.0 and 2.5 km/h respectively. The total quality of pod was found 176.41, 180.21 and 173.91 gm and pod damage percentage was found 4.37, 4.36 and 4.73 % at forward speed of 1.5, 2.0, 2.5 km/h. The cost of harvesting by developed digger cum heap formater was found to be ₹ 371.98 /h.
Estimation of Spinal Loading during Palletizing under Restricted Height and Poor Lighting
Authors: Davis Kermit G
Published: November 2020

Many industries have areas with restricted spaces where manual material handling occurs which is oftentimes further complicated by poor lighting. The study objective was to evaluate the spine loading when lifting boxes within restricted height space with different light levels. Ten participants lifted boxes with independent variables: restricted height, light levels, pallet layer, and pallet position. The dependent variables included three-dimension spine loads and rating of perceived exertion. The results indicate that importance of location of the box as well as the restricted height of the space where the box is being lifted (increase of about 1200 N in compression and 160 N in A-P shear). Under general lifting conditions, light level had minimal impact (under 100 N). Gender was also found to have a significant impact for lateral shear and A-P shear forces (males > females for lateral shear but < for A-P shear). Overall, restricted height and location of on the pallet had the greatest impact on the spine loads.
A Comprehensive Key for Identification of the “Swarming Conehead” Ruspolia Differens Serville, 1838 (Orthoptera: Tettigoniidae) Occurring in the Afro - Tropical Region
Authors: ND Matojo
Published: November 2020

This work reviewed t h e behavioural, morphological and molecular characteristics of the lo n g - h o rned g r a ss h opp e r R u s po l i a d i f f e r e n s S e r v i l le or “ s en en e ” i n S wa h i li name ( O r t h op t e ra T e t t i g o n ii da e ), as apparent in literature. On that basis, the work has generated a comprehensive key for identification of this species. As widely known, this insect native to Afro - tropical region where it is widely edible and it ha s a characteristic s w a rm i n g behaviour that strikingly occurs during rainy season. Also, it has c o l ou r polymorphism with a total of six key sympatric colour forms, sex d i m o r p hi sm with m al e s possessing longer antennae and a u n i q u e pair o f active tongue - like m e t a t h o r a c i c f l a p s whereas the females have a corresponding pair of vestigial metathoracic nodules. Furthermore, t he species has a pair of distinct subequal black markings on the mid and hind tibia near the knee joint and a white inter - ocular oval mark that appears like a s imple eye. Its sister species which is Ruspolia nitidula S c o p o l i as verified by molecular phylogenetics i s e xc l u s i v e l y s ol i t a r y , mostly g r e en i sh an d P a l ea rc t i c r an g i n g i n A s i a , E u r op e a n d N o r t h e r n A f r i c a. Since swarming behaviour is a foremost diagnostic feature differentiating R. differens from other coneheads, it is worthwhile to demarcate the species with a common name “Swarming Conehead” adding to the existed names.