Amplitude Of Lateral Displacement Research Articles

Tire Rubber Based Microplastic Particles Cause Adverse on Quality Parameters of Rainbow Trout Sperm Cells.

In the present study, we aimed to determine the parameters of oxidative stress markers, motility and kinematics of rainbow trout (Oncorhynchus mykiss) sperm cells exposed to different doses (0.001, 0.01, 0.1, 1.0, and 10mg/L, in vitro 4h) of tire rubber based microplastic particles (TRMP-Ps) the leachates procedure of rubber pieces. First of all, TRMP-Ps were prepared by abrasion method in accordance with the literature. Structural and morphological features of TRMP-Ps were determined by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) methods, respectively. Energy dispersive X-ray (EDX) analysis technique was used to characterize the elemental composition of TRMP-Ps. Particle size of microplastic structures was measured hydrodynamically with dynamic light scattering analysis (DLS). After exposure, the effect of TRMP-Ps was defined by the observations of kinematics and antioxidant activities in sperm cells. Our findings showed that the straight line velocity, the curvilinear velocity, the angular path velocity, and the amplitude of lateral displacement of sperm cells decreased. Moreover, while the level of superoxide dismutase decreased dose-dependently against the toxicity of TRMP-Ps, no significant change was observed in the levels of malondialdehyde and total glutathione. The 4-h median effective concentrations (EC50) of TRMP-Ps based on mobility parameters of sperm ranged from 0.31mg/L for reduced straight line velocity of sperm cells to 0.51mg/L for reduced amplitude of lateral displacement of the spermatozoa head. Therefore, we concluded that TRMP-Ps can be a risk for the reproduction cycle of fish in aquatic environments.

Brushing rams before and during electroejaculation improves sperm motility and kinetics with slight changes in stress biomarkers

The aim of this study was to determine whether brushing rams before and during electroejaculation (EE) reduces their stress response and improves the characteristics of the ejaculate. A single person brushed each ram for 5 min daily, for 15 days, in an individual pen. Semen was collected from five rams brushed before and during EE by the same brusher, while the other five were electroejaculated without being brushed. The treatments were exchanged three days later, so semen was collected from all the rams with both treatments. Brushing increased mass motility (P = 0.05), and curvilinear (P = 0.001), linear (P = 0.02), and average path (P = 0.01) velocities of sperm, as well as the average amplitude of lateral displacement of the sperm head (P = 0.05), and tended to increase sperm concentration (P = 0.09). Brushing tended to reduce the cortisol concentration (P = 0.06) and the duration of head movements when 2 V pulse series V was applied (P = 0.1). Brushing increased creatine kinase concentration (P = 0.04) and tended to increase rectal (P = 0.06) and maximum eye surface temperatures (P = 0.1), total time, and number of electrical pulses administered (P = 0.07 for both variables), as well as the sum of pulses per voltage applied during EE (P = 0.06). In rams accustomed to being brushed by the same person, brushing them before and during EE improved semen quality, with slight changes in the stress responses.

Testicular alterations and semen quality in a selected group of breeding buffaloes.

Testicular ultrasound enables the evaluation of changes in the testicular parenchyma. This study aimed to report the occurrence of hypoechogenic testicular alterations and their relationship with semen quality in five breeding buffaloes. Two buffaloes presented with hyperechoic points characteristic of fibrosis and anechoic density content between the parietal and visceral tunica. The two bulls without ultrasonographic changes showed higher average trajectory speed, linear velocity, curvilinear velocity, amplitude of lateral displacement of the spermatic head, total motility, progressive motility, fast speed, and acrosomal membrane values within the normal range. The number of spermatozoa with major and total defects was higher in the group of animals without alterations. The three buffaloes that presented with testicular alterations produced semen within established freezing standards.

Effect of dietary omega-3 polyunsaturated fatty acids supplementation of Astyanax lacustris males on semen quality

Abstract This study aimed to verify whether the inclusion of omega-3 polyunsaturated fatty acids (PUFAs-ô3) in the diet of Astyanax lacustris males improves seminal quality. Four hundred fish were arranged in 20 boxes of 180 L in the recirculation system. These were fed with isoprotein diets (32% CP), until apparent satiation, with four levels of marine fish oil rich in PUFAs-ô3 inclusion (In% = 0, 3, 6, and 9), for 105 days. After, males were hormonally induced to spermiation, and semen was collected after 226 ATUs. Parameters evaluated were osmolality, seminal volume and color, spermatic concentration, sperm morphology, membrane integrity and, sperm motility (total and progressive motility, velocity curvilinear, straight line and average path, linearity and rectilinearity coefficients, trajectory oscillation, head lateral displacement amplitude, and cross-beat frequency). Seminal volume was greater in the In-0 and In-3 groups. Inclusion of PUFAs-ô3 positively influenced the kinetic parameters, as treatment with 6% and 9% of inclusion fish oil resulted in higher values for most of these parameters and did not differ statistically from each other. Thus, it is concluded that the addition of PUFAs-ô3 to the feed of breeders significantly improved the seminal quality of A. lacustris males.

VIV Fracture Investigation into 3D Marine Riser with a Circumferential Outside Surface Crack

Vortex-induced vibration (VIV) is one of the most common dynamic mechanisms that cause damage to marine risers. Hamilton’s variational principle is used to establish a vortex-induced vibration (VIV) model of a flexible riser in which the wake oscillator model is used to simulate cross-flow (CF) and inline flow (IL) vortex-induced forces and their coupling, taking into account the effect of the top tension and internal flow in the riser. The VIV model is solved by combining the Newmark-β and Runge–Kutta methods and verified with experimental data from the literature. Combining Option 1 and Option 2 failure assessment diagrams (FADs) in the BS7910 standard, a fracture failure assessment model for a marine riser with circumferential semielliptical outside surface cracks is established. Using the VIV model and FAD failure assessment chart, the effects of riser length, inside/outside flows, and top tension on the VIV response and safety assessment of marine risers with outside surface cracks are investigated. It is shown that increasing the top tension can inhibit the lateral displacement amplitude and bending stress in a riser, but excessive top tension can increase the axial stress in the riser, which counteracts the decrease in the bending stress, so that the effect of top tension on crack safety is not significant. The increasing outside flow velocity significantly increases the lateral vibration amplitude and bending stress in the riser and reduces the crack safety. When other parameters remain unchanged, increasing riser length has no significant effect on the vibration amplitude of the lower part of the riser.

Cryobank of Mediterranean Brown Trout Semen: Evaluation of the Use of Frozen Semen up to Six Hours Post-Collection

The aim of this study was to evaluate the effects of different cold-storage time intervals between collection and semen-freezing on both fresh and cryopreserved semen motility parameters and the post-thaw fertilizing ability of Mediterranean brown trout semen. The ejaculates were split into six aliquots and stored on ice from 1 to 6 h, until freezing. Fresh and post-thaw sperm motility was evaluated by a Computer-Assisted Sperm Analysis system, whilst the fertilizing ability was assessed by in vivo trials. In fresh semen, at 3 h of storage, a significant decrease of total motility, linear movement (STR, LIN) and beat cross frequency (BCF) was recorded, whilst the amplitude of lateral displacement of the spermatozoon head (ALH) underwent a significant increase. In frozen semen, no significant difference was observed for all the motility parameters evaluated, except for the total motility between 1 and 6 h of storage and the duration of sperm movement between 1 and 5 h. Cold-storage time did not significantly affect the percentage of live embryos following the use of frozen semen. In conclusion, our results showed that, if necessary, the Mediterranean brown trout semen can be frozen even until 6 h post-collection without losing its fertilizing ability.

Finite-Element Analysis of Pipelines with Axial Walking and Lateral Buckling

A pipeline is prone to axial movement, called pipeline walking, under heat-up and cooldown cycles. The build-up of axial force along the pipeline can result in the phenomenon referred to as lateral buckling. Walking and lateral buckling can both influence pipeline movement performance and threaten the safety of pipeline systems. The numerical simulation method is adopted to study the pipeline movement laws under walking and buckling interactions. Walking and buckling interactions are classified into three types for different forms of seabed slopes, and corresponding mitigation methods are proposed. The effects of buckling number, route bend, sleeper spacing, and anchor position on the lateral displacement amplitude, axial displacement, and effective axial force (EAF) of the pipeline are analyzed. Criteria for the mitigation methods are proposed based on parameters such as the pipeline end expansion, buckling failure parameter, maximum anchor force, and minimum compressive EAF. The results show that the anchor position has a great influence on the intertransformation of pipeline buckling and walking. The difference in anchor force can reach 51.1% considering different anchor positions.

Analytical study on controlled lateral thermal buckling of antisymmetric mode for subsea pipelines triggered by sleepers

Subsea pipelines exposed to high temperature and high pressure (HTHP) conditions is susceptible to lateral buckling. In order to control lateral buckling, engineered buckle initiators, such as sleepers, are introduced to initiate planned lateral buckles along the pipeline at specific locations in order to ensure that the stress in each lateral buckle remains acceptable. In this study, taking the interaction of adjacent buckles into account, analytical solutions of antisymmetric lateral buckling mode triggered by sleepers are derived. With the proposed formulations, the method to obtain the accurate locations of lateral displacement amplitude and maxima of bending stress is presented and discussed. And a detailed comparison between symmetric and antisymmetric mode of lateral buckling triggered by single sleeper is presented. Moreover, the influence of the sleeper spacing on controlled lateral buckling behaviour with the consideration of axial interaction between adjacent buckles is conducted. Finally, a detailed analysis about the influence of the sleeper height, lateral frictional coefficient and submerged weight of the pipeline on the controlled post-buckling behaviour is presented. Our results show that, for smaller sleeper friction or smaller sleeper height, the symmetric mode is more likely to happen, while the antisymmetric mode is prone to occur for larger sleeper friction and larger sleeper height. One effective method to reduce displacement amplitude and maximum stress is to decrease the sleeper spacing. The minimum critical temperature difference decreases with increasing sleeper height and increases with increasing lateral friction coefficient or submerged weight of the pipeline. And an alternative way to reduce the maximum stress is to reduce the lateral friction coefficient or submerged weight of the pipeline even though the displacement amplitude increases.

Experimental measurement of monotonic and cyclic lateral resistance of risers and pipelines in Gulf of Mexico clays

The location near the touchdown zone of a steel catenary riser at the seabed is a primary “hot spot” for fatigue assessment, with seabed stiffness having a major influence on the predicted fatigue life. This paper presents the results of laboratory model tests in the lateral direction with the motivation to appropriately capture the fundamental mechanism of soil interaction with the pipeline or riser in the lateral direction. The objectives of this study are to evaluate (i) the fundamental mechanism of soil interaction with the pipeline or riser in the lateral direction subjected to monotonic and cyclic loading, (ii) the evolution of lateral resistance with different (small to large) displacement amplitudes, (iii) the degradation of lateral resistance while increasing the number of cycles, and (iv) the recovery of the soil strength with time. The primary findings from the tests are that (i) the lateral resistance on the riser–pipeline drops sharply after trench formation, (ii) the lateral resistance across the trench approaches zero and reaches a steady state at a large number of cycles, (iii) the shape of trenches depends on the lateral displacement amplitude and the initial penetration depth, and (iv) some regain in strength occurs after a period for consolidation.

The protective effects of Vitamin C and Trolox on kinematic and oxidative stress indices in rainbow trout sperm cells against flower‐like ZnO nanoparticles

This study investigated the protective effects of 1 mM Vitamin C and 1 mM Trolox on kinematic and oxidative stresses in rainbow trout (Oncorhynchus mykiss) sperm cells against flower-like zinc oxide nanoparticles (ZnO-NP, 1 mg/L) in vitro, during 2 hr. Trolox showed protective effects on all kinematic parameters measured for sperm cells against ZnO-NPs, whereas Vitamin C only affected angular path velocity (VAP), linearity (LIN) and amplitude of lateral displacement of the sperm cell head (ALH). Although ZnO-NPs reduced total glutathione (TGSH) and catalase (CAT) compared with the control, there were positive treatment effects for both Trolox and Vitamin C on antioxidant capacity. Conversely, while ZnO-NP increased the rate of malondialdehyde (MDA) lipid peroxidation, it decreased following antioxidant therapy. This research suggests that Trolox and Vitamin C play a protective role for rainbow trout sperm exposed to ZnO-NP.

Comparative analyses of reproductive characteristics of functional sex reversal male gynogenetic red crucian carp and ordinary male red crucian carp

Functional sex reversal male gynogenetic red crucian carp (RGRCC) were obtained by oral administration of 17-α-methyltestosterone (MT) at a dosage of 100 μg/g diet for 60 days to gynogenetic red crucian carp. In the present study, we aim to investigate whether MT induction sex-reversal impairs morphology and reproductive function of RGRCC. During the reproductive season, 20 mature males of both ordinary red crucian carp (RCC) and RGRCC were randomly chosen to measure the phenotypic traits and reproductive traits. None of the morphological traits and nor sperm traits measured differed significantly between RGRCC and ordinary male RCC (P > .05). The mean body weight, gonadosomatic index (GSI), sperm concentration, sperm volume and fertilization rate of RGRCC and ordinary male RCC, were 265.92 and 270.71 g, 3.74 and 3.82%, 3.04 and 3.22 × 1010 cells ml−1, 8.73 and 8.87 kg ml−1, 84.66% and 86.84%, respectively. In addition, six sperm motility parameters including values of curvilinear velocity, average path velocity, straight line velocity, linearity, percentage of motile sperm and amplitude of lateral displacement of the sperm head were assessed by computer assisted sperm analysis and there were not significant differences (P > .05) between these two fishes. We concluded that the reproductive capacities of RGRCC were not affected by MT treatments. RGRCC could be used to obtain all-female RCC which will increase their production potential for application in aquaculture.

Analytical study of third-mode lateral thermal buckling for unburied subsea pipelines with sleeper

Unburied subsea pipelines operating under high-temperature and high-pressure conditions tend to relieve their axial compressive force by forming lateral buckles. In order to manage lateral buckling, a sleeper is often employed as a buckle-initiation technique to ensure pipeline integrity. In this study, analytical solutions of third-mode lateral buckling for unburied subsea pipelines with sleeper are derived. The analytical solution is compared with experimental data in the literature and shows good agreement. The stability of the buckled pipeline is investigated by means of an energy analysis and it is found that third-mode lateral buckling has lower energy than first-mode buckling, which means that third-mode buckling is more likely to happen in practice. The influence of sleeper height and sleeper friction on lateral post-buckling behaviour is illustrated and analysed, with particular attention paid to the minimum critical temperature difference, lateral displacement amplitude and maximum stress. Our results show that increasing the height of the sleeper or decreasing the friction between pipeline and sleeper can both be used to decrease the minimum critical temperature difference, but their influence on the maximum stress is opposite.

144 Dynamic of Sperm Subpopulations in Red Deer Capacitated Samples

An ejaculate is a mixture of sperm subpopulations (SP) with varying motility characteristics. Moreover, males with high percentages of fast and linear-moving sperm have high rates of fertility (Ramón et al. 2003 Biol. Reprod. 89, 110). The objective was to assess dynamics, over time, of SP of capacitated red deer sperm. Thawed sperm were selected with 45/90% Percoll, diluted at 10 × 106 sperm mL−1 in SOF plus 10% oestrous sheep serum and incubated for 2 h at 38.5°C under 5% CO2. Sperm motility was assessed by computer-assisted semen analysis at 1, 5, 15, 30, 45, 60, and 120 min and 24 h. Sperm were classified as described previously (Martínez-Pastor et al. 2005 Biol. Reprod. 72, 316-327) and the evolution of SP during capacitation was characterised with piece-wise regression that identified change points. Five sperm SP were identified based on velocity according to an actual path (VCL), velocity according to a straight path (VSL), velocity according to the average, smoothed path (VAP), linearity (LIN), straightness (STR), wobble (WOB), amplitude of lateral displacement of sperm head (ALH), and frequency of the flagellar beat (BCF). Sperm in SP1 were fast, linear sperm with high ALH; they corresponded to capacitated sperm. In contrast, SP5 were slow, non-linear sperm, with low ALH (Table 1). The dynamics of each SP differed over time was different along the time. Percentages of SP1, SP4, and SP3 were significantly decreased at 60, 90, and 100 min, whereas percentages of SP2 and SP5 did not change over time. This study was consistent with previous reports that kinematic sperm characteristics change over time. Table 1.Sperm subpopulations (SP) based on kinematic end points.

Analytical solution for lateral buckling of unburied subsea pipelines with distributed buoyancy section

Unburied subsea pipelines operating under high temperature and high pressure (HT/HP) conditions tend to relieve their axial compressive force by forming lateral buckles. Uncontrolled lateral buckling can lead to pipeline failure. In order to control lateral buckling phenomenon, distributed buoyancy method is employed as buckle initiation technique. In this study, analytical solutions for lateral buckling of unburied subsea pipelines with distributed buoyancy section are derived. Fitting method is used to get the relationship between the equivalent axial compressive force and the half-length of the buckled section. The influence of the length and the weight of the distributed buoyancy section over typical behaviors of lateral buckling is illustrated and analyzed. The results show that increasing the length of distributed buoyancy section or decreasing the weight of distributed buoyancy section can all be used to decrease the minimum critical temperature difference and reduce the maximum axial compressive stress. However, the corresponding lateral displacement amplitude increases. The best selection of the weight of distributed buoyancy section is about half reduction of the original weight of pipeline.

The effect of temperature and pH on the motility and viability of ostrich sperm

As the chemical environment of semen diluents can have a profound effect on sperm quality, we examined the effect of temperature and pH on the motility and viability of sperm in the ostrich. Semen was collected from four males, each male being replicated three times. Ejaculates were diluted and incubated for 10min at 20°C and 40°C in four different buffers, temperature adjusted at pH 6, 7, 8 and 9 respectively. Average path velocity (VAP), curvilinear velocity (VCL), straight-line velocity (VSL), linearity (LIN), beat cross frequency (BCF) and amplitude of lateral displacement (ALH) were then recorded for each sample using CASA. The viability of sperm was assessed using nigrosin–eosin staining. Sperm incubated at 40°C had higher motility parameters, except for ALH. At 40°C, VAP, VSL and LIN increased with pH while VCL, BCF and ALH were higher for lower pHs. The viability of sperm was not affected by temperature but decreased at pH values>7. A pH in the neutral range appeared to yield higher quality sperm after in vitro storage at 20°C. However, the effect of different pH levels and temperatures on sperm longevity needs to be investigated further to develop viable ostrich specific diluents.

Dynamic Response of the Casing String in Seabed Soil for Deepwater Drilling

The marine riser has transfer dynamic cyclic load to the top of casing string when deepwater drilling operating. Considering with the nonlinear characteristics of seabed soil, the variable string cross section, and the axial load on the top of string, a dynamic differential equation of casing string below mud line and its numerical solution were established. Results illustrate that, the lateral displacement, the bending moment, and the shear of the casing string are not equal when lateral dynamic cyclic loading achieves amplitude due to the soil hysteresis effect. The diameter and wall thickness of conductor have less affect to string vibration frequency, cannot adjust the string natural frequency by adjusting these parameters. The natural frequency of casing string in sand is bigger than it in clay. The undrained shear strength of soil has great effect on the natural frequency of casing string in clay. The lateral displacement amplitude is highest when the vibration frequency of casing string at its natural frequency.

Assessment of Aseismic Performance of Ballasted Track with Large-scale Shaking Table Tests

This study uses full-scale models subjected to shaking table tests to evaluate the aseismic performance of ballasted track. The authors also tested for lateral ballast resistance force with the ballasted track model after shaking. Results show that in the case of ballasted track with no countermeasures, the amplitude of lateral displacement and the residual displacement increased because the lateral resistance of ballasted track significantly decreased when the earthquake acceleration acting on the ballasted track exceeded around 800 gals. The decrease in lateral ballast resistance force could be prevented by applying adequate countermeasures against track buckling. An iron plate for was found to be the most effective countermeasure against track buckling.

Does the Microbial Flora in the Ejaculate Affect the Freezeability of Stallion Sperm?

In an attempt to evaluate the possible relationship between the microbial flora in the stallion ejaculate and its ability to freeze,three ejaculates from five stallions were frozen using a standard protocol. Before freezing, an aliquot was removed for bacteriological analysis. Bacterial growth was observed in all the ejaculates studied. The isolated microorganisms were:Staphylococcus spp. and Micrococcus spp. (in all the stallions), beta-haemolytic Streptococcus (in stallions 3 and 4), Corynebacterium spp. (in stallions 1, 3-5), Rhodococcus spp. (in stallion number 2), Pseudomonas spp. (in stallion number 1) and Klebsiella spp. (in stallions 1, 3 and 5). The presence and richness of Klebsiella and beta-haemolytic Streptococcus in the ejaculate were related to two sperm variables post-thaw,namely the proportion of dead spermatozoa (ethidium+ cells; r = 0.55, p < 0.05) and the amplitude of lateral displacement of the sperm head (ALH, microm; r = -0.56, p < 0.05), respectively.The degree of growth of Corynebacterium spp. in the ejaculate was positively correlated with the percentage of spermatozoa showing high caspase activity post-thaw(r = 0.62, p < 0.05). The presence and number of colonies of beta-haemolytic Streptococcus were negatively correlated (r = -0.55, p < 0.05) with low sperm caspase activity. It is concluded that the microbial flora of the equine ejaculate maybe responsible for some of the sublethal damage experimented by the spermatozoa during cryopreservation.

Use of computerized motility analyzer for the evaluation of frozen-thawed ram spermatozoa.

A computerized motility analyzer (CellTrak/STM) was calibrated for its use with ram semen. Adjustment of the several setup variables allowed an accurate measurement of kinetic parameters such as percentage of motile cells, straight velocity, curvilinear velocity, linearity and amplitude of lateral displacement of the head. All kinetic parameters, except the lateral displacement of the head, showed significant changes after freezing and thawing. The curvilinear velocity exhibited the least significative post-thaw decrease. The alterations in kinetic parameters provoked by freezing and thawing could account for the low success obtained with frozen semen by cervical insemination, as it is accepted that during the initial steps of fertilization high motility and linearity are required.

Effects of exposure of pre-pubertal boars to di(2-ethylhexyl) phthalate on their frozen-thawed sperm viability post-puberty

Late effects of pre-pubertal oral exposure to di(2-ethylhexyl) phthalate (DEHP), a plastic softener used in, for example, polyvinyl chloride-products, on semen quality in young boars have not been clear-cut. The aim of this study was to determine whether stress imposed on spermatozoa would reveal such effects. Semen was collected from post-pubertal boars (8-9 months of age), which had been exposed to 300 mg kg(-1) body weight of DEHP per os three times a week from 3 to 7 weeks of age and from control siblings given placebo (water). The semen was cryopreserved and examined for plasma membrane integrity post-thaw using the short hypo-osmotic swelling test and flow cytometry (propidium iodide /SYBR-14). Sperm motility was assessed by computer-assisted sperm analysis. No significant difference in plasma membrane integrity could be found between the groups. The DEHP-exposed group had a significantly lower percentage of linearly motile spermatozoa at 30 min (P < 0.05) and 120 min (P < 0.001) after thawing, and a larger amplitude of lateral displacement of the head 120 min after thawing (P < 0.05), compared with controls. In summary, spermatozoa from boars pre-pubertally exposed to low doses of DEHP, showed kinematic deviations post-thaw that could be related to DEHP exposure.