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Objective: Iron element has critical roles such as myelin synthesis and neurotransmitter synthesis. Critical enzymes and proteins strictly control iron metabolism. Alterations in the enzyme activities could modify iron metabolism. Metabolic and endocrine changes may influence iron turnover in patients with major depression and anxiety disorders. Materials and Methods: 30 patients with major depressive disorder (MDD), 30 with anxiety disorders (ADs) according to the DSM 5 criteria, and 30 healthy controls were included. Hamilton Depression and Anxiety Scales were the clinical evaluation tools. Blood samples were collected 12 hours of fasting. Hepcidin and Ferroportin levels were measured with ELISA method. Results: Both Hepcidin and Ferroportin levels were lower in the MDD group compared to the ADs group, Hepcidin levels were found to be statistically significantly lower (p= 0.014). In addition, an inverse correlation was observed between the Hamilton Depression Scale score and Ferroportin levels (r= -0.214, p

Rattling is a perennial gear noise problem observed in various powertrain components ranging from manual transmissions to engine balancers and timing gear trains. Under lightly loaded conditions, gear systems that are subjected to input and/or output torque fluctuations exhibit vibro-impacts as tooth separations and coast-side contacts take place in the presence of backlash. Experimental set-ups that can impose tightly controlled torque fluctuations to single or multi-mesh gear train are used here to determine the sensitivity of the rattling noise levels to the magnitudes of backlash within wide ranges of torque fluctuation parameters. Torsional discrete models of the experimental set-ups were used to simulate these rattling motions and to predict impact velocity-based rattle severity indexes as a function of both excitation parameters and backlash magnitudes. Single-mesh results show that the larger backlash values result in higher noise levels in most of the cases. In case of double-mesh systems, the resultant noise levels and the corresponding rattle indices exhibit different sensitivities to backlash magnitudes depending on the excitation conditions.

Biofilm-associated infections cause important health problems all over the world. Because of the resistance to antimicrobials and their possible side effects, researchers' attention has been focused on plant extracts and their components. The aim of this study is to evaluate the antimicrobial and antibiofilm potentials of Salvia microstegia Boiss. et Bal. mericarps. The antimicrobial activity of ethanolic extract obtained from the mericarps was evaluated using the microdilution method against seven standard bacteria and three standard yeast strains. In addition, the effect of the extract on inhibiting biofilm formation and preformed biofilm of Pseudomonas aeruginosa was determined using the crystal violet method. The used extract showed moderate to low antimicrobial activity against tested bacteria and yeasts with minimum inhibitory concentration (MIC) values ranging from 62.5 to 250 µg/mL. Moreover, the extract's potential to inhibit preformed biofilms was found to be greater compared to its potential to inhibit biofilm formation. In conclusion, the tested extract obtained from Salvia microstegia mericarps showed antibiofilm potential, however, additional studies involving different strains are needed to reveal its antimicrobial potential in a more holistic perspective.

The power loss of bearings is a significant factor in the overall efficiency in a drive unit system. Such bearings are subject to combined radial and axial loading needed to support the gear mesh forces. An experimental methodology has been developed to perform sets of power loss measurements on TRB, 4PCBB and DGBB. These measurements were performed under a variety of speed, load, temperature, and lubrication conditions. The loss behaviors of these types of the bearings are discussed, along with the tradeoff of different bearing arrangements for the fuel economy cycles. Several power loss models are employed to assess the accuracy of the estimations as compared to the experimental measurements. At low speed some models showed good correlations for TRB and DGBB, while at higher speed, they start deviating from the testing results. A higher fidelity model for estimating the losses at high speed, especially speed around 20krpm and beyond, needs to be developed. For 4PCBB, the models showed under prediction for the losses within the testing range.

In this study, an experimental methodology is presented for measuring power losses of rolling element bearings under combined radial and axial loading conditions. The set-up developed for this purp...

Gear tooth bending fatigue failures are instantaneously catastrophic to gear drive power transmission systems. For this reason, gear designers must understand the limits of their design with respect to the desired application and service time. Fatigue testing on gear specimens has been preferred metric on which to base future designs. Single Tooth Bending test (STB) or a Rotating Gear (RG) test methodologies have been used for this purpose. STB type tests generally form the large majority of gear fatigue testing due to cost and availability but does not fully simulate the actual operating conditions of rotating gears in service. As RG evaluations are costly and time-consuming, it is desirable to quantify how a stress-life (SN) relationship regressed through STB testing compares to that produced in RG testing. In this study, both STB and RG test methodologies are employed to test the same specimen design. Matrices of fatigue tests are executed and statistical regression techniques are used to estimate bending fatigue lives as a function of stress for both sets of data. The resultant SN curves are compared to determine any differences in allowable stress. Techniques are then employed using single set data (STBF or RG individually) to demonstrate the calculation of correlation coefficients, which can approximate the total difference determined between the two data sets.

External fluctuation torques acting on gear trains having clearances often cause vibro-impact motions with resultant rattle noise issues. In this study, an impact velocity-based rattle severity parameter that correlates with the resultant rattling noise is proposed for multimesh gear trains. An experimental setup is employed to measure torsional vibro-impact motions and the corresponding sound pressure levels of a three-axis gear train under various torque fluctuation conditions. A discrete torsional model of the experimental setup is developed and validated through comparisons to the vibration measurements. An impact velocity-based rattle severity index defined from the predicted response is proposed and shown to correlate well with the measured rattle noise sound pressure levels within a wide range of operating conditions. The demonstrated ability of the proposed rattle severity index in tracking rattle noise allows for the assessment of rattle consequences of a multimesh drivetrain solely from its predicted torsional response.

In general, gear mechanical loss is associated with the friction of the lubricating contact surface of the gear and bearing that transmit the power, and a no-load spin loss which is load independent occurs due to gear rotation and the interaction of the bearing component with the lubricating element. In order to minimize planetary gear loss, it is desirable to design by checking the efficiency at the concept design stage. However, a design technique that considers the noise and efficiency of a planetary gear set simultaneously has not been achieved so far. In this paper, a program called 'pRMC with EHL' to check together the efficiency and noise that affected by gear specifications has been developed. By using developed program, planetary gear sets specifications have been designed. And through the experimental evaluation, automatic transmission efficiency could be reduced by 0.3% in combination fuel consumption mode and the planetary gear vibration could be also reduced by 10 dB than former design. Through this designing verification and input parameter correlation, a new planetary gear set designing process has been come up with successfully at the concept design stage.

Gear induced noise represents a major part of overall automotive drivetrain noise. Gear rattle noise is caused by strongly nonlinear dynamic behavior of the gear pair, primarily due to external torque of speed fluctuations under lightly loaded conditions. Such loading conditions cannot be generated by using the conventional gear dynamics test set-ups that employ power recirculating gearbox arrangements or conventional electric motors. In this paper, a new test set-up is introduced to emulate the actual torque/velocity fluctuations of the input and/or output members of a gear train through three-phase synchronous servo-motors. In addition to establishing backlash boundaries, a pair of absolute encoders are used to measure the relative motions of the gears as well as their impacts along the drive and coast sides flanks or gears. Torsional vibratory behavior of a gear pair is presented at different backlash values under several input/output fluctuation conditions along with the companion sound pressure measurements.

The fatty acid, sterol, and tocol compositions, mineral, total phenolic, and flavonoid contents, and antioxidant and antimicrobial activities of Salvia longipedicellata Hedge (endemic) mericarps were examined for the first time. Mericarps were rich in α-linolenic acid (47.72%), β-sitosterol (54.46%), γ-tocopherol (375.68 mg/kg), and potassium (75.411 μg/g). Total phenolic and flavonoid contents were 1.04 μg GAE/mg extract and 0.32 μg QE/mg extract, respectively. The antioxidant and antimicrobial potential of mericarps were also determined.

In this study, a rough surface thermal elastohydrodynamic lubrication (TEHL) model tailored for the simulation of high-speed and high-temperature contacts of relatively smooth surfaces is introduce...

This article describes the development of a high-speed, two-disc tribometer to conduct traction and scuffing tests emulating typical aerospace and automotive gear contacts. This tribometer is capab...

Dynamic response of a gear pair subjected to input and output torque or velocity fluctuations is examined analytically. Such motions are commonly observed in various powertrain systems and identified as gear rattle or hammering motions with severe noise and durability consequences. A reduced-order torsional model is proposed along with a computationally efficient piecewise-linear solution methodology to characterize the system response including its sensitivity to excitation parameters. Validity of the proposed model is established through comparisons of its predictions to measurements from a gear rattle experimental setup. A wide array of nonlinear behavior is demonstrated through presentation of periodic and chaotic responses in the forms of phase plots, Poincaré maps, and bifurcation diagrams. The severity of the resultant impacts on the noise outcome is also assessed through a rattle severity index defined by using the impact velocities.

Vibro-impacts are common in various automotive engine and transmission gear applications. They are known to cause excessive noise levels, often called rattling or hammering. Input and output fluctuations acting on such systems cause tooth separations and sequences of impacts allowed by backlash at the gear mesh interfaces. The fluctuations leading gear rattling have often been studied for specific applications with the excitations produced typically by an internal combustion engine. As such, rattle evaluations have been often empirical and specific to the systems considered. In this study, an experimental test setup of a gear pair is developed to emulate the same torque fluctuations in a laboratory environment. This setup is used to establish an impact velocity-based rattle severity index defined by the measured torsional behavior of the drive train that is shown to correlate well with the measured sound pressure levels. With that, a validated dynamic model of the experimental setup is employed to predict the same index to allow estimation of rattle noise outcome solely from a torsional dynamic model of the drivetrain. Predicted rattle severity indexes are shown to agree well with the measured ones within wide ranges of torque fluctuations and backlash magnitudes, allowing an assessment of rattle performance of a drivetrain solely from a torsional model.

BACKGROUND/AIM Permanent daylight saving time has been implemented in Turkey since 2016. The present study determines the characteristics of road traffic collisions in the short-term, trauma severity, and whether permanent daylight saving time has an impact on these parameters. MATERIALS AND METHODS Drivers admitted because of road traffic collisions to a tertiary care university hospital emergency service two weeks before and after the transition to wintertime in 2014 and 2015 and summertime in 2015 and 2016 as well as those admitted two weeks before and after the same period with permanent daylight saving time in 2016 and 2017 wintertime and 2017 and 2018 summertime were included in the study. Trauma severity was measured using the Injury Severity Score. RESULTS The study analysed the data of 710 patients. There was no statistically significant difference was found between admissions in the summertime and permanent daylight saving time periods in terms of gender, time of admission, week of admission, Injury Severity Score and outcome (P > .05 for all values). CONCLUSIONS In this study, we examined the short-term effects of daylight saving time on road traffic collisions, and demonstrated that it had no impact on the number or time of admission, trauma severity and patient outcomes. More comprehensive studies covering longer periods can be performed across the country.

The pollen grains of 19 Turkish Salvia species in Aethiopis, Drymosphace, Hemisphace, Hymenosphace and Salvia sections, 13 of which are endemic to Turkey, were investigated, documented and illustrated through Light Microscopy (LM) and Scanning Electron Microscopy (SEM). This study provides pollen data of 14 species for the first time. The pollen grains of the species examined are monads, isopolar, radially symmetrical and hexacolpate, mostly medium in size, slightly elliptic to more or less circular in polar view and mainly oblate-spheroidal in equatorial view. Two different ornamentation types are recognized on exine sculpturing; reticulate-perforate and bireticulate. The present results do not generally support the traditional infrageneric classification of Salvia, but provide useful pollen characters for species delimitation.

Leucojum aestivum (snowflake) contains galantamine, a medication used for the treatment of Alzheimer's disease. However, polyphenolic compounds of this species were not studied earlier. Proper understanding of the polyphenolics in the species and their antioxidant properties may lead to a review of their medical use. Therefore, in this study, the polyphenolic content of L. aestivum was determined by UV spectrophotometric and HPLC methods. DPPH, ABTS+, and RPC assays were performed for assessment of its antioxidant potential. Flower and leaf extracts of L. aestivum were found to have more antioxidant activity than its bulbs. This result demonstrated that it was an important source of antioxidant compounds. Qualitative and quantitative findings showed that it contained significant amounts of polyphenols. Naringenin, rosmarinic, pcoumaric, syringic, and gallic acid compounds were identified in the leaf and flower extracts. Methanol extracts of the fowers, leaves and bulbs had no activity against pathogenic bacterial strains. The methanolic flower and leaf extracts showed the most antifungal effective against Alternaria citri. Moreover, they were found to be a slightly antifungal effective against Penicillium glabrum and Cladosporium cladosporioides. Anatomical studies were performed on leaf transverse and surface sections of L. aestivum and its bulb cross-section. The isobilateral leaf had tetracytic type of stomata. The mesophyll comprised arge lysigenous cavities and contained crystalline inclusions (raphide crystals). Large amounts of compound starch grains were recognized to occur in parenchyma cells in the bulb. SEM observations revealed that leaf epidermal cells had conspicuous boundaries and their membranes on periclinal walls were striate. © 2019 Academic Press. This study is a part of the M.Sc. dissertation of the first author at Department of Molecular Biology and Genetics at the Institute of Natural and Applied Sciences, Usak University, Usak, Turkey. We thank Prof. Dr. Safiye Elif Korcan at Usak University for her help in antimicrobial and antifungal studies.

Salvia L., the largest genus of the family Lamiaceae, is composed of many well-known plants of medicinal value. This study provides the first data on micromorphology, myxocarpy, mineral content and in vitro antimicrobial and antiproliferative activities of mericarps of Salvia pilifera, considered to be a vulnerable endemic species from Turkey. The macro-and micromorphological mericarp traits were documented and illustrated via stereo microscopy and scanning electron microscopy. Mineral content of mericarps was analyzed using ICP-MS. Ethanol extract of mericarps was tested against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Acinetobacter baumannii, Aeromonas hydrophila, Candida albicans, Candida tropicalis, and Candida glabrata using broth microdilution method. Antimycobacterial activity was performed against Mycobacterium tuberculosis H37Rv using resazurin microtiter plate method. Ampicillin, Ethambutol, Isoniazid, and Fluconazole were chosen as reference drugs. Antiproliferative effect of the extract was tested against A549 human lung cancer cell lines using MTT test. The size of the mericarps was 4.38±0.17 mm in length and 3.28±0.13 mm in width. The general shape was elliptic to widely elliptic. The abscission scar was nearly rounded. The ornamentation pattern of the surface was colliculate with polygonal exocarp cells. Myxocarpy was observed on the surface of the mericarps when they become hydrated. Transparent mucilaginous cells showed a moderate reaction with extensions more than 0.1 mm long. Potassium and calcium were determined as major minerals (80.662±0.234 and 41.892±0.399 µg/g, respectively). The extract showed greater antibacterial activity against A. baumannii compared to Ampicillin (62.5 and 125 µg/mL MIC values, respectively). Cell viability level of the extract (100 ?g/mL) was found to be statistically lower than control group against A549 human lung cancer cell lines (P

A tribo-dynamic model of ball bearings is proposed to predict their load-dependent (mechanical) power losses. The model combines (i) a transient, point contact mixed elastohydrodynamic lubrication (EHL) formulation to simulate the mechanics of the load carrying lubricated ball-race interfaces and (ii) a singularity-free dynamics model and establishes the two-way coupling between them that dictates power losses. The dynamic model uses a vectoral formulation with Euler parameters. The EHL model is capable of capturing two-dimensional contact kinematics, velocity variations across the contact as well as asperity interactions of rough contact surfaces. Resultant contact surface shear distributions are processed to predict mechanical power losses of example ball bearings operating under combined radial and axial forces. An experimental setup is introduced for measurement of the power losses of rolling-element bearings. Sets of measurements taken by using the same example ball bearings are compared with those predicted by the model to assess its accuracy in predicting mechanical power loss of a ball bearing within wide ranges of axial and radial forces.

In this study, an experimental methodology is presented to separate various components of the power loss of a gearbox. The methodology relies on two separate measurements. One is designed to measure total power loss of a gearbox housing a single spur gear pair under both loaded and unloaded conditions such that load-independent (spin) and load-dependent (mechanical) components can be separated. With the assumption that gear pair and rolling element bearings constitute the bulk of the gearbox power loss, a second measurement system designed to quantify rolling element bearing losses is proposed. With this setup, spin and mechanical power losses of rolling element bearings used in the gearbox experiments are measured. Combining the sets of gearbox and bearing data, power loss components attributable to the gear pair and rolling element bearings are quantified as a function of speed and torque. The results indicate that all gear and bearing related components are significant and a methodology such as the one proposed in this study is warranted.

In this study, a non-Newtonian, transient, isothermal, mixed elastohydrodynamic lubrication (EHL) model is proposed for helical gear contacts. The model accounts for nonelliptical contacts subject to spatially varying sliding and rolling velocity fields that are not aligned with any principal axis of the contact region, which is the case for helical gear contacts. The time-varying changes pertaining to key contact parameters and relative motion of roughness profiles on mating tooth surfaces are captured simultaneously to follow the contact from the root to the tip of a tooth while accounting for the transient effect due to relative motions of the roughness profiles. Actual tooth load distributions, contact kinematics, and compliances of helical gear contacts are provided to this model by an existing helical gear load distribution model. Measured three-dimensional roughness profiles covering the entire meshing zone are incorporated in the analyses to investigate its impact on the EHL conditions as well as mechanical power loss. Results of a parametric sensitivity study are presented to demonstrate the influence of operating conditions and surface roughness on the EHL behavior and the resultant gear mesh mechanical power loss of an example helical gear pair. The accuracy of the proposed mixed-EHL model is assessed by comparing the mechanical power loss predictions to available experimental results.

The quasi-static behaviors of a double-helical gear pair is investigated both experimentally and theoretically with the main focus on the influence of the key design and manufacturing parameters associated with double-helical gears, including nominal right-to-left stagger angle, the stagger angle deviation (error) from the nominal stagger angle, and axial gear supporting conditions. On the experimental side, a double-helical gear test setup proposed earlier (Kang, M. R., and Kahraman, A., 2015, “An Experimental and Theoretical Study of Dynamic Behavior of Double-Helical Gear Sets,” J. Sound Vib., 350, pp. 11–29). for studying dynamics of the same system is employed that allows adjustable right-to-left stagger angles, intentional stagger errors, and axial support conditions. Specific measurement systems are developed and implemented simultaneously to measure the static motion transmission error and axial motions of the gears under low-speed conditions, as well as gear root strains to determine right-to-left load-sharing factors. A test matrix that covers wide ranges of stagger angles, intentional stagger error, and axial support conditions is executed within a range of torque transmitted to establish an extensive database. On the modeling side, the measured quasi-static behavior of double-helical gear pairs is simulated by using an existing quasi-static double-helical load distribution model (Thomas, J., and Houser, D. R., 1992, “A Procedure for Predicting the Load Distribution and Transmission Error Characteristics of Double Helical Gears,” World Congress-Gear and Power Transmission, The 3rd World Congress—Gear and Power Transmission, Paris.). Direct comparison of the measurements and predictions of loaded static transmission error, axial play, root stresses, and right-to-left load-sharing factors are used to validate the quasi-static model as well as describing the measured behavior.

High-cycle gear tooth bending fatigue lives of spur gears under fully reversed and fully released loading conditions are compared in this experimental study. The experimental methodology described in an earlier publication, (Hong et al. 2020, “A Rotating Gear Test Methodology for Evaluation of High-Cycle Tooth Bending Fatigue Lives Under Fully Reversed and Fully Released Loading Conditions,” Int. J. Fatigue, 133, p. 105432. 10.1016/j.ijfatigue.2019.105432), is employed to perform two sets of rotating, gear tooth bending fatigue tests. Statistical analyses are performed to regress stress versus life (S–N) curves under both loading conditions. These curves indicate that a gear under fully reversed loads has a shorter bending life at the same maximum tooth root stress as a gear under fully released loads. Various planetary gear set kinematic conditions with different stationary members are considered to determine the equivalent number of tooth loading cycles per revolution of the sun gear. They are combined with established S–N curves under both loading conditions to determine the ratios of allowable maximum tooth root stresses amongst the gear components of a P-planet gear set such that each gear in the set has the same bending fatigue life. A “stress-balanced” gear set designed to these stress ratios is expected to have the same bending fatigue life for its sun, ring, and planet gears, ensuring that the planetary gear set life is the longest.

BACKGROUND/AIM: Coronavirus 2019 disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a pandemic infectious disease that causes morbidity and mortality. As a result of high mortality rate among the severe COVID-19 patients, the early detection of the disease stage and early effective interventions are very important in reducing mortality. Hence, it is important to differentiate severe and non-severe cases from each other. To date, there are no proven diagnostic or prognostic parameters that can be used in this manner. Due to the expensive and not easily accessible tests that are performed for COVID-19, researchers are investigating some parameters that can be easily used. In some recent studies, hematological parameters have been evaluated to see if they can be used as predictive parameters. MATERIALS AND METHODS: In the current study, almost all hematological parameters were used, including the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio, monocyte/lymphocyte ratio, mean platelet volume to lymphocyte ratio, mean platelet volume to platelet ratio, plateletcrit, and D-dimer/fibrinogen ratio (DFR), neutrophil/lymphocyte/platelet scoring system, and systemic immune-inflammation index. A total of 750 patients, who were admitted to Ankara City Hospital due to COVID-19, were evaluated in this study. The patients were classified into 2 groups according to their diagnosis (confirmed or probable) and into 2 groups according to the stage of the disease (non-severe or severe). RESULTS: The values of the combinations of inflammatory markers and other hematological parameters in all of the patients with severe COVID-19 were calculated, and the predicted values of these parameters were compared. According to results of the study, nearly all of the hematological parameters could be used as potential diagnostic biomarkers for subsequent analysis, because the area under the curve (AUC) was higher than 0.50, especially for the DFR and NLR, which had the highest AUC among the parameters. CONCLUSION: Our findings indicate that, the parameters those enhanced from complete blood count, which is a simple laboratory test, can help to identify and classify COVID-19 patients into non-severe to severe groups.

Introduction: This study aims to determine the use of thiol/disulphide homeostasis parameters together with procalcitonin (PCT), C-reactive protein (CRP) and Multinational Association for Supportive Care in Cancer (MASCC) risk scoring system for the prediction of prognosis and mortality in the patients with febrile neutropenia presenting to the emergency department. Material and methods: The study was carried out prospectively on 53 patients with febrile neutropenia and 51 healthy subjects presenting to the emergency department. Thiol/disulphide homeostasis parameters, which are oxidative stress markers, were measured through a new method developed by Erel and Neselioglu. PCT and CRP were also measured. Patients were grouped in to high-risk and low-risk groups in terms of prognosis and mortality through MASCC scores. Results: Mean values of disulphide/native thiol, CRP and PCT were found to be significantly higher in the patients having febrile neutropenia (p=0.029, p

In this study, a method to predict the contact friction coefficients at the rolling‐sliding contacts of isotropic superfinished and axially ground gear and bearing surfaces in wind turbine gearboxes is proposed. A two‐disc test rig was used to measure friction coefficient values within a slide‐to‐roll ratio range of −0.8 to 0.8, rolling velocities of 2 to 12 m/s, at oil temperatures of 50°C, 70°C, and 100°C and Hertzian contact pressures of 1.2, 1.6, and 2.0 GPa. A polyalphaolefin (PAO) International Standards Organization (ISO) viscosity grade (VG) 320 was the lubricant. Data from 90 individual friction coefficient tests were combined to develop two closed‐form friction coefficient formulae. A multivariable linear regression analysis was used to derive the regressed formulae. Using the developed regressed formulae, the predicted friction values follow the trend of measured values at all of the operating conditions. The results show that the regressed formulae are close to experimental friction coefficient values. The friction coefficient predictions confirm that the regressed formulae are capable of simulating contact friction values for the lubricated contact conditions considered. Post-print / Final draft

Several medicinal plants to treat diabetic wound healing were researched and are still under investigation. A variety of processes contributed to diabetics such as; inhibition of inflammatory response, generation of reactive oxygen species, differentiation of the extracellular matrix and reduced collagen production . The purpose of this study was to examine the ultrastructural alterations in diabetic rat skin tissue treated with the ointment prepared with Salvia euphratica. Male Wistar albino rats were used in this study (n: 24), divided into 4 groups. Non-treated, diabetic, diabetic and cicatrizant treated, ointment prepared with ethanol extract of 1% Salvia euphratica topically applied for 14 days. A single dose of 45 mg/dL streptozotocin (i.p.) was given to rats to induce diabetes. Excisional wound model was created under anesthesia. A cicatrizant, fitocream, was used as positive control. Normal skin tissue was observed in non-treated group. Diabetic skin tissue revealed hyalinization of the cytoplasm and loss of cytoplasm. Ointment treated diabetic group revealed altered cellular elements suggests healing. At the wound area, number of fibroblast cells synthesizing connective tissue were increased and the collagen fibers were regularly oriented. Neutrophil and monocyte cells besides mast and macrophage cells were found in the capillaries of dermis in S. euphratica ointment treated group. Wound healing in diabetic tissues is known to be slow. Using phytocream therapy to expedite the healing process is a long time known phenomenon. Our observations demonstrated that Salvia euphratica promoted changes in skin tissue that may contribute to wound healing at the cellular level.

This study examined the detailed chromosome measurements and karyotype asymmetries of seven taxa in the genus Vicia. The taxa are V. articulata, V. cassubica, V. villosa subsp. villosa in sect. Cracca, V. noeana var. noeana, V. sativa subsp. sativa, V. peregrina in sect. Vicia and V. caesarea in sect. Ervum. V. cassubica, V. noeana var. noeana, V. sativa subsp. sativa, V. caesarea have 2n = 12 chromosomes. V. articulata, V. villosa subsp. villosa, V. peregrina have 2n = 14 chromosomes in somatic cells. Total chromosome lengths range between 2.93–4.99 µm in V. articulata, 2.09–4.73 µm in V. cassubica, 1.86–3.36 µm in V. villosa subsp. villosa, 4.23–6.05 µm in V. noeana var. noeana, 2.07–3.72 µm in V. sativa subsp. sativa, 4.32–7.21 µm in V. peregrina and 2.39–5.78 µm in V. caesarea. The detailed chromosome measurements, relative lengths, centromeric indexes and karyotype asymmetries are also given. V. articulata is the most symmetrical karyotype, while V. villosa subsp. villosa is the most asymmetrical karyotype in intrachromosomal asymmetry including parameters of MCA, AsK, TF, Syi, A1, and A. However, the asymmetrical karyotypes are different in interchromosomal asymmetries. While V. noeana var. noeana is the most symmetrical karyotype in CVCL, Rec, and A2. V. caesarea is the most asymmetrical karyotype in only CVCL and A2. Unlike all parameters, V. cassubica is the most asymmetrical karyotype in Rec value. The scatter diagrams are given between MCA–CVCL and Syi–Rec. © 2018, © 2018 Dipartimento di Biologia, Università di Firenze.

This study focuses on a class of dynamic behavior observed in spur gear pairs as a parametrically excited system. Stiffness at the gear contact interface that couples the gear bodies is a periodically time-varying due the fluctuation of number of tooth pairs in contact. In presence of such stiffness fluctuation as part of the excitations, various published studies predicted subharmonic resonances near speeds that are integer multiples of the speed at which the primary resonance occurs, with little or no validation. This study presents an extensive experimental investigation to show such subharmonic resonances and various associated period-n motions ( n ≥ 2 ) under both transient and steady-state conditions. A test set-up and a pair of test gears developed for this purpose are described along with solutions to various measurement and data processing challenges. Two different models of the gear pair, a purely torsional discrete model and a deformable-body model, are employed, and their predictions are compared to the measured period-1 and period-n motions to assess their accuracy.

Lamiaceae familyasi icindeki Nepetoideae alt familyasinin Mentheae oymagina ait olan Salvia L. (adacayi) cinsi tibbi, sus bitkisi, gida ve h alusinojenik kullanimlari nedeniyle ile iyi bilinmektedir. Bu cinsin Hemisphace Benth. seksiyonu Turkiye’de uc tur ile temsil edilir. Bu guncel calisma, ilgili seksiyona ait morfolojik olarak birbirine benzeyen iki Salvia turu uzerine yurutulmustur: Salvia napifolia Jacq. ve S. russellii Benth. ( S. verticillata L. haric). Bu amac icin, soz konusu turlerin perikap ince yapisi isik ve gecirimli elektron mikroskobu (TEM) yardimiyla detayli olarak arastirilmistir. Morfometrik karakterler coklu karsilastirmalar icin tek yonlu Varyans Analizi (ANOVA) ile Tukey’in tam olarak onemli fark (HSD) post-hoc testi kullanilarak analiz edilmistir. Perikarp ozelliklerinin taksonomik onemi tartisilmistir. Calisilan turlerin ayrimina izin veren en onemli ozellikler; perikarp, mesokarp ve sklerenkima bolgesinin kalinligidir. Her iki turun islatilmis merikarplarinin yuzeyinde miksokarpi (musilaj olusumu) gorulmustur. Musilajli hucreler orta duzeyde bir reaksiyon gostermistir, fakat S. napifolia ’daki musilajli tabaka biraz daha kalindir (yaklasik 0.20-0.34 mm). Bu calisma incelenen turlerin perikarp ince yapisi uzerine ilk detayli bulgulari sunmaktadir.

In this paper, a load distribution model for a double-planet planetary gear set is developed by modifying an existing single-planet planetary gear set model [1] to account for an additional planet to planet gear mesh and their impact on phasing relationship among different sun-planet, planet-planet and planet-ring gear meshes. Similar to the single-planet planetary gear set model, the double-planet planetary gear set model accounts for effects of various component and system level variations such as supporting conditions, gear tooth modifications, manufacturing errors and kinematic configurations. The double-planet planetary gear load distribution model is derived for both rigid and flexible ring gear rim, while only parametric studies for a rigid ring gear rim is presented in this paper to demonstrate load distribution characteristics of double-planet planetary gear sets with different planet bearing stiffness and combination of various types of manufacturing errors, including pin hole position error and runout errors.

Power losses of load carrying gear and bearing components of automotive transmissions have become a major research area in recent years. Measurement of power loss of a gearbox is a routine task where losses from rolling element bearings, gear meshes and seals collectively define the total loss. However, separating bearing and gear mesh losses is not possible, as a gear mesh cannot be operated without support bearings. This study aims at developing a methodology for measuring power losses of rolling element bearings of different types operated under realistic load, speed and temperature conditions. A test machine concept is implemented to apply combined radial and axial loads to a pair of test bearings in a stable and repeatable manner, with rotational speed and lubrication parameters controlled tightly during tests. The proposed test methodology is employed to evaluate power loss for three different types of bearings. Load-dependent and load-independent components of power loss are separated, and influence of speed and load values on bearing mechanical loss are quantified. A repeatability study of the machine and methodology is also presented to demonstrate the accuracy of the proposed setup.

Noise and vibration performance of a gear system is critical in any engineering industry. Excessive vibrational amplitudes originated by the excitations at the gear meshes propagate to the transmission housing to cause noticeable noise, while also increasing gear tooth stresses to degrade durability. As such, gear designers must generate designs that are nominally quiet with low-vibration amplitudes. This implies a gear pair fabricated exactly to the specifications of its blue print will be acceptable for its vibration behavior. Achieving this, however, is not sufficient. As the manufacturing of gears require them to be subject to bands of tolerances afforded by the manufacturing processes employed, the designers must be concerned about variations to the performance of their presumably quite baseline designs within these tolerance bands. This research aims at demonstrating how one type of manufacturing error, random tooth spacing errors, alter the vibratory behavior of a spur gear pair. Two pairs of spur gears are tested for their dynamic transmission error performance. One gear pair with no tooth spacing errors form the baseline. The second gear pair contain an intentionally induced random sequence of spacing errors. The forced vibration responses of both gear pairs are compared within wide ranges of speed and torque. This comparison shows that there is a clear and significant impact of random spacing errors on spur gear dynamics, measurable through examination of their respective transmission error signatures. In the off-resonance regions of speed, vibration amplitudes of the random error pair are higher than the no-error baseline spur gear pair. Meanwhile, at or near resonance peaks, the presence of random spacing errors tends to lower the peak amplitudes slightly as compared to the no-error baseline spur gear pair. The presence of random spacing errors introduces substantial harmonic content that are non-mesh harmonics. This results in a broadband frequency spectrum in addition to an otherwise well-defined frequency spectrum with gear-mesh order components, pointing to an additional concern of noise quality.

For a gear pair, both the contact pattern and the transmission error (TE) significantly impact durability and fatigue life. Design and manufacturing processes are often aimed at improving the contact pattern and reducing the overall TE. Other errors, such as runout and wobble, are often induced during the installation of power transmission systems, and they can alter the contact pattern and TE of an otherwise well-designed gear pair. This study provides a methodology to experimentally investigate the impact of wobble errors on the contact pattern and static transmission error (STE) of helical gears. It first provides a description of the modifications to an existing test machine. Next, it describes the gear specifications, preliminary testing matrix, data acquisition and processing procedure, as well as the experimental results obtained with regards to both the contact pattern and STE. The following are observed while describing the experimental results. For a test with no wobble and no runout, the contact pattern remains the same at every rotational position. However, by introducing even a small amount of wobble, the contact will shift from one side of the face width of the gear to the opposite side of the face width of the gear within one revolution. Introduction of wobble may increase the STE and sideband activity around gear mesh harmonics, especially as torque increases. Yet the modest increases in STE and sideband activity seen with the introduction of wobble are not enough to make definitive conclusions. The feasibility of the modified test setup has been demonstrated, and preliminary results have been presented. However, additional data collection should be completed in order to study the impact of runout and wobble on both spur and helical gear pairs with various microgeometry modifications and manufacturing errors.

Increased apoptotic cell death in uremic patients has been confirmed by a variety of studies. The present study aimed to investigate the effect of uremic toxins and duration of hemodialysis (HD) therapy on apoptosis by means of measuring serum caspase cleaved CK18 (CCCK-18) levels. Seventy chronic HD patients were recruited and divided into three groups with differing periods of HD, from 6 months to 10 years. Twelve healthy subjects served as controls. Serum CCCK-18 level was found significantly higher in HD patient groups (Group 2; 189 ± 71 IU/L, Group 3; 182 ± 65 IU/L, Group 4; 204 ± 111 IU/L) as compared to the control group (122 ± 20 U/L) (P < 0.05). When all hemodialysis patients considered together serum CCCK-18 showed positive correlation with serum uric acid and phosphorus (P < 0.05). In conclusion, our results suggest that apoptosis is enhanced in HD patients, phosphorus and uric acid might play a role in this increment, but duration of HD therapy has no effect on apoptosis.

Objective The aim of this study was to evaluate whether quercetin (QUER) treatment could have a protective effect against oxidative stress induced by homocysteinemia in rats. Materials and methods Thirty-two male Sprague-Dawley rats (adult) were assigned randomly to four groups: the control group was given physiological saline (PS; 1.5 mL/d); the QUER group was given QUER (50 mg/kg body weight [BW] daily) in distilled water and 0.25 mL PS; the homocysteine (HCY) group was given HCY (1 mg/kg BW daily) in distilled water and 1.25 mL PS; and the QUER + HCY group was given QUER 1 h before the administration of HCY. QUER, HCY, and PS were injected intraperitoneally every other day for 30 d. Plasma malondialdehyde (MDA), carbonyl, erythrocyte-reduced glutathione (GSH), plasma sulphydril (−SH) levels, erythrocyte catalase (CAT), and superoxide dismutase (SOD) activities were determined. Results Plasma CAT levels in the QUER group were found to be significantly higher than in the control group, whereas plasma MDA levels in the QUER group significantly decreased compared with the control group. In the HCY group, plasma MDA and carbonyl levels significantly increased and GSH and SOD levels significantly decreased compared with the control group. Plasma MDA levels significantly decreased and GSH and CAT levels significantly increased in the QUER + HCY group compared with the HCY group. Plasma −SH levels were significantly lower in the HCY group than in the control group. Plasma −SH levels were higher in the QUER + HCY group than in the HCY group, but they were not significant. Conclusion The exposure of rats to HCY leads to oxidative stress reflected in increased MDA and decreased antioxidant enzyme levels. Administration of QUER might attenuate oxidative damage induced by HCY or have a protective effect against it.

Automotive automatic transmissions typically use a planetary gear train to transmit power at a number of desired output-to-input speed ratios. This is achieved by connecting the gear sets forming the train in various ways as well as connecting certain members to the input and outputs shafts as well as friction elements to hold them stationary. As the gear train is coaxial, the connections between the members of the gear sets as well as input, output and fixed member connections must be planar (i.e. do not intersect) for the transmission to be assemblable. This paper proposes a methodology to perform such planarity (assembly) checks to examine if kinematic configurations of a given concept design for an automatic planetary gear train be mechanically assembled by using a vertex addition algorithm based on graph theory. The proposed methodology is demonstrated through selected planar and non-planar transmission examples.

This study proposes a methodology to predict power losses of automotive axle units, including both load-dependent (mechanical) and load-independent (spin) loss components. This methodology combines a mechanical hypoid gear mesh power loss model, a new tapered roller bearing mechanical power loss model, a gear drag loss model, and empirical viscous bearing power loss formulae to determine the total power loss of an axle unit. The proposed methodology captures the effects of operating conditions (speed and torque and oil temperature and level), contact surface roughness amplitudes, as well as bearing preload on power loss. The model is employed to simulate published axle efficiency experiments. Direct comparisons between measured and predicted power losses are presented to demonstrate the accuracy of the proposed modeling methodology.

Objective: Pediculated groin flap has been playing an important role in hand reconstructive surgery for a long time. In this study, the cases where pediculated groin flap in the reconstruction of soft tissue defects of the hand was used are presented in terms of literature. Material and Methods: The cases included in the study where a groin flap was used for hand defects between 2010 and 2014 in the Plastic, Reconstructive, and Aesthetic Surgery Department. The age, gender, reason of defect, its localization, groin flap size, donor area closure method, flap separation time, other treatments, and complications were thoroughly examined. Results: Twenty-two groin flaps were used in 13 male and 7 females. It was used to close the amputated part in 8 patients as a result of finger amputation and degloving injury, in 3 patients as a result of hand and finger crush defect, in 1 patient as a result of burn finger defect, in 5 patients for extension contracture, and in 3 patients for flexion contracture due to burn sequel. Flap loss was not recorded in any of the cases. Conclusion: Pediculated groin flap is a good alternative that can be easily and safely used in suitable cases and has an important place in the reconstruction of hand defects.

This study proposes a scuffing model for spur gear contacts. A heat transfer formulation is devised to evaluate gear bulk temperature, with frictional heat flux yielded from thermal mixed elastohydrodynamic lubrication (EHL) analysis. In return, the bulk temperature is fed back into the EHL modeling to determine tribological behavior within contact zone, including flash temperature. After bulk temperature stabilizes, the bulk and flash components are added to arrive the total surface temperature, whose maximum is compared to a scuffing limit for failure determination. Utilizing the model, a set of simulations is performed to demonstrate the influences of surface roughness and rotational speed on scuffing load.

In order to accurately predict ring gear deformations and to investigate the effects of ring gear flexibility on quasi-static behaviors of planetary gear sets, a complete load distribution model of planetary gear sets having flexible ring gears will be formulated here based on the baseline model proposed by the same authors (Hu, Y., Talbot, D., and Kahraman, A., 2018, “A Load Distribution Model for Planetary Gear Sets,” ASME J. Mech. Des., 140(5), p. 053302). Direct comparisons to published experiments are provided to assess the accuracy of the proposed load distribution methodology. Example analyses with flexible ring gear rims are performed indicating that ring gear flexibility could influence gear mesh-level and planetary gear set system-level behaviors. Influence of spline supporting a ring gear is also investigated revealing that positions of planet branches with respect to external splines could influence ring deflections and resultant gear mesh load distributions.