Follicle size and reproductive hormone profiles during a post-weaning altrenogest treatment in primiparous sows

2015 ◽  
Vol 27 (2) ◽  
pp. 304 ◽  
Author(s):  
J. J. J. van Leeuwen ◽  
M. R. T. M. Martens ◽  
J. Jourquin ◽  
M. A. Driancourt ◽  
A. Wagner ◽  
...  
Keyword(s):  
High Frequency ◽  
Fold Increase ◽  
High Amplitude ◽  
Daily Administration ◽  
Reproductive Hormone ◽  
Diurnal Pattern ◽  
Once Daily ◽  
Follicular Wave ◽  
Follicle Size ◽  
Low Amplitude

This study investigated the endocrine background of follicle size changes during post-weaning altrenogest treatment. altrenogest-treated sows received a 20-mg dosage daily at 8.00 a.m. from Day –1 to Day 14 after weaning. On Day –1, only 3/13 altrenogest-treated sows showed LH pulses compared with 8/8 control sows (P = 0.001). On Day 0, control sows showed a typical high frequency–low amplitude LH pattern, indicative for recruitment of oestrogenic follicles. In altrenogest-treated animals on Day 0, half of the sows showed high frequency–high amplitude pulses from 4–5 h after weaning. In altrenogest-treated sows, average follicle size increased from 3.1 ± 0.5 mm on Day 0 to 4.4 ± 0.6 mm on Day 5, then decreased to 3.7 ± 0.5 mm on Day 7 and stabilised thereafter. FSH and oestradiol (E2) concentrations showed a distinct diurnal pattern; high at 7.00 a.m. and low at 3.00 p.m. E2 concentrations (7.00 a.m.) showed a 2.5-fold increase from Day –1 to Day 2, and subsequently a 2-fold decline to reach a plateau at Day 8. FSH concentrations reached maximum levels by Day 5 and slowly declined afterwards. In conclusion, once-daily administration of altrenogest starting one day before weaning delays the weaning-induced increase in LH pulses. Although FSH and follicle size increase until Day 5 after weaning, follicle E2 production already decreased from Day 2 after weaning. Post-weaning altrenogest treatment thus results in a follicular wave of follicles that lose oestrogenic competence at Day 2 after weaning, presumably related to the changed LH dynamics during altrenogest treatment.

Vibrational Fatigue Analysis of a Strain Loading Using the Frequency and Wavelet Filtering Methods

2011 ◽  
Vol 462-463 ◽  
pp. 124-129
Author(s):  
Shahrum Abdullah ◽  
Edisah Putra Teuku ◽  
Zaki Nuawi Mohd. ◽  
Mohd. Nopiah Zulkifli
Keyword(s):  
High Frequency ◽  
Filter Design ◽  
High Amplitude ◽  
Morlet Wavelet ◽  
Wavelet Filtering ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Automotive Components ◽  
Low Pass ◽  
Low Amplitude

This paper presents a comparison work between the filtering methods of fatigue strain loadings using the frequency spectrum and the wavelet transform (WT), in which a raw loading signal can be simplified for purpose of simulation. For this reason, the Fast Fourier Transform (FFT) and the Morlet wavelet algorithms were used in order to transform the vibrational fatigue time series into the frequency domain signal, leading to the observation of the frequency characteristics of the signal. To retain high amplitude cycles in the FFT algorithm, a low pass filter technique was applied to remove the high frequency signals with small amplitude that are non-damaging. The departure of high frequency information smoothed the low amplitude cycles at high frequency events in the fatigue signal. The Butterworth filter was selected as the most efficient filter design as it retained most of the fatigue damage and also had the capability to remove 30 % of the original low amplitude cycles. On the other hand, the Morlet wavelet managed to remove 64 % of the original 59 second signal. This wavelet filtering method removed 34 % more than the similar procedure applied through the FFT approach. Hence, this fatigue data summarising algorithm can be used for studying the durability characteristics of automotive components.

The Motion of Strawberry Leaves in an Air-Assisted Spray Field and its Influence on Droplet Deposition

2021 ◽  
Vol 64 (1) ◽  
pp. 83-93
Author(s):  
Shuo Wu ◽  
Jizhan Liu ◽  
Jiangshan Wang ◽  
Dianhe Hao ◽  
Rongkai Wang
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
High Amplitude ◽  
Azimuth Angle ◽  
List Type ◽  
Droplet Deposition ◽  
Inclination Angles ◽  
Turbulence Effect ◽  
Spray Field ◽  
Low Amplitude

HighlightsA visualization method for the motion of strawberry leaves in an air-assisted spray field is proposed.Strawberry leaves showed two motion states in different critical velocity ranges of the sprayer airflow.The airflow instability and the turbulence effect are considered important factors for the leaf vibrations.A strawberry leaf azimuth angle in the range of 90° to 270° can provide good deposition with smaller droplets.Abstract. The reasonable motion of crop plants in an air-assisted spray field can improve droplet deposition. Therefore, this study focuses on the motion of strawberry leaves and the droplet deposition mechanism in an air-assisted spray field. First, this study proposes a descriptive method for strawberry leaf motion in an air-assisted spray field and clarifies the important influence of strawberry leaf motion on droplet deposition. Second, an experiment was performed on the motion and droplet capture of single strawberry leaves in multi-position postures in an air-assisted spray field. The results showed that the leaves had two motion states (i.e., low amplitude with low frequency and high amplitude with high frequency) at different airflow velocities and inclination angles, and the critical airflow velocity corresponding to the two motion states was determined to be 8.7 m s-1. When the azimuth angle of the strawberry leaves is in the range of 90° to 270°, a reasonable inclination angle of the airflow and the high frequency and high amplitude vibration state of the leaves driven by the airflow will provide good deposition and canopy penetration of droplets with smaller diameters. Keywords: Air-assisted spray field, Droplet deposition, Motion, Spray, Strawberry leaves.

scholarly journals Mechanistic Characteristics of Double Dominant Frequencies of Acoustic Emission Signals in the Entire Fracture Process of Fine Sandstone

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3959 ◽  
Author(s):  
Chuangye Wang ◽  
Xinke Chang ◽  
Yilin Liu ◽  
Shijiang Chen
Keyword(s):  
Frequency Band ◽  
High Frequency ◽  
Fracture Process ◽  
Low Frequency ◽  
High Amplitude ◽  
Dominant Frequency ◽  
Band Energy ◽  
Ae Signal ◽  
Low Amplitude ◽  
Frequency Band Energy

To determine the intrinsic relationship between the acoustic emission (AE) phenomenon and the fracture pattern pertaining to the entire fracture process of rock, the present paper proposed a multi-dimensional spectral analysis of the AE signal released during the entire process. Some uniaxial compression AE tests were carried out on the fine sandstone specimens, and the axial compression stress–strain curves and AE signal released during the entire fracture process were obtained. In order to deal with tens of thousands of AE data efficiently, a subroutine was programmed in MATLAB. All AE waveforms of the tests were denoised by wavelet threshold firstly. The fast Fourier transform (FFT) and wavelet packet transform (WPT) were applied to the denoised waveforms to obtain the dominant frequency, amplitude, fractal, and frequency band energy ratio distribution. The results showed that the AE signal in the entire fracture process of fine sandstone had a double dominant frequency band of the low and high-frequency bands, which can be subdivided into low-frequency low-amplitude, high-frequency low-amplitude, high-frequency high-amplitude, and low-frequency high-amplitude signals, according to the magnitude. The low-frequency amplitude relevant fractal dimension and the high-frequency amplitude relevant fractal dimension each had turning points that corresponded to significant decreases in the middle and end stages of loading, respectively. The frequency band energy was mainly concentrated in the range of 0–187.5 kHz, and the energy ratios of some bands had different turning points, which appeared before the complete failure of the rock. It is suggested that the multi-dimensional spectral analysis may understand the failure mechanism of rock better.

Recovery non-drug therapy in treatment of diabetic fabularis syndrome in patients with diabetes mellitus type 2

2015 ◽  
Vol 9 (1) ◽  
pp. 0-0
Author(s):  
Аль-Замиль ◽  
M. Al-Zamil ◽  
Божко ◽  
S. Bozhko ◽  
Кудаева ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
High Frequency ◽  
Inflammatory Process ◽  
High Amplitude ◽  
Motor Deficit ◽  
Motor Deficits ◽  
Control Group ◽  
Low Amplitude ◽  
Corticosteroid Injections

The purpose of this work was to study clinical efficiency of the periosteal corticosteroid injections, a monophasic high-frequency low-amplitude electrical neuro-stimulation, a monophasic low-frequency high-amplitude electrical neuro-stimulation and the acupuncture in the treatment of fibularis syndrome (FS) in pa-tients with type 2 diabetes mellitus (DM-2). Materials and methods. From 2004 to 2014, 183 patients (121 women and 62 men) with a diagnosis of FS suffering from DM-2 in the stage of compensation were under medical supervision. All patients (27 people – control group) had a pharmacotherapy for treatment FS and DM-2. 78 patients had additionally a course periosteal corticosteroid injections (the 1-st group), 25 patients had a course monophasic high-frequency low-amplitude electrical neuro-stimulation (the 2-nd group), 29 people – a course monophasic high-frequency low-amplitude electrical neuro-stimulation; 24 patients – a course of acupuncture (the 4-th group). Pain, neurological status and electromyographic state peroneal nerves were studied before and after treatment. Conclusion. Periosteal corticosteroid injections in combination with TF are the most effective method in the treatment of FS in patients with DM-2. The reduction in pain, regression of the inflammatory process in the peroneal nerve and reducing the severity EMG violations were noted. The second highest decrease of pain syn-drome is the combination of the TF MVN the TENS, motor deficit and EMG - violations in the background of this treatment weren’t significantly changed. The use of the TENS in combination with TF and RTIs in combina-tion with TF reveals a reduction in pain, motor deficits and the severity of the inflammatory process in the pero-neal nerve, without significant changes of the EMG.

An Experimental Investigation of Energy Transfer from a High- Frequency Mode to a Low-Frequency Mode in a Flexible Structure

1995 ◽  
Vol 1 (1) ◽  
pp. 115-128 ◽  
Author(s):  
Pavol Popovic ◽  
Ali H. Nayfeh ◽  
Kyoyul Oh ◽  
Samir A. Nayfeh
Keyword(s):  
Energy Transfer ◽  
High Frequency ◽  
Power Spectra ◽  
Low Frequency ◽  
Excitation Amplitude ◽  
High Amplitude ◽  
Frequency Mode ◽  
High Frequency Mode ◽  
Beam Frame ◽  
Low Amplitude

The objective of the present article is to experimentally observe and characterize the transfer of energy from low-amplitude, high-frequency modes to high-amplitude, low-frequency modes. The subject of the study is a three-beam frame. The excitation amplitude is restricted to below 2 g peak. The authors have focused on observing, characterizing, and documenting the excitation of the first mode by high-frequency forcing. The energy-transfer processes are identified by power spectra and characterized further by frequency and amplitude sweeps. The energy-transfer routes observed in the experiment are subharmonic resonance of order one-half, combination resonance of the additive type, and interaction between widely spaced modes. In the latter route, an excitation at a frequency that is more than 100 times the first-mode frequency has been observed to excite the first mode.

Design of a Retrofittable Spindle Attachment for High Frequency Vibration-Assisted Drilling

2014 ◽  
Author(s):  
J. Panju ◽  
M. Meshreki ◽  
M. H. Attia
Keyword(s):  
High Frequency ◽  
High Speed ◽  
Low Frequency ◽  
Cutting Parameters ◽  
High Amplitude ◽  
Spindle Attachment ◽  
Vibration Assistance ◽  
Low Amplitude ◽  
Thrust Forces ◽  
Conventional Drilling

Conventional drilling of modern super alloys and composite material induces high stresses in the vicinity of drilled holes along with high thrust forces which lead to problems in terms of hole quality and accuracy as well as increased tool wear. A recent and promising technique to overcome these challenges is to introduce vibration assistance in the cutting zone by superimposing oscillating vibration in the feed direction of the tool. Two regimes of vibration excitation could be applied for this purpose: low frequency (<500 Hz) high amplitude (>100 μm) and high frequency (>500 Hz) low amplitude (<20 μm). Motivated by the advantages of the HF-VAD and the limited work available in the literature for this regime, a new system is developed by the authors where the rotating tool is excited to high frequency and low amplitude. The new design is based on the use of piezoelectric actuators to generate the motion and a high speed slip ring to ensure the transfer of sufficient power to the actuator. A novel concept was implemented by de-coupling the rotary motion of the spindle from the vibrational motion of the actuator to ensure a higher efficiency of power transmission without damaging either the actuator or the spindle. With this design, a retrofittable HSK 100A toolholder with high frequency excitation spindle attachment was manufactured to incorporate drill sizes up to 1/4 inches. Commissioning tests were performed under no load and spring loaded conditions and it was found that the system has a capability to excite the tool up to 100 μm at 900 Hz (resonance frequency) and up to 5 μm between 500–800 Hz and 1100–2500 Hz. HF-VAD tests were conducted using this new attachment on Aluminum 6061 and it was found that the system was able to successfully obtain the prescribed frequency and amplitude. Up to 50% reduction in thrust forces was obtained in HF-VAD in comparison to conventional drilling under same cutting parameters; this is associated with finer chips with break off serrations.

SEISMIC STRATIGRAPHIC EVALUATION OF A NEOCOMIAN SUBMARINE FAN SYSTEM, BROWSE BASIN, NORTH WEST SHELF

1992 ◽  
Vol 32 (1) ◽  
pp. 171
Author(s):  
L.R. Miller ◽  
W.J. Stuart
Keyword(s):  
High Frequency ◽  
Seismic Reflection ◽  
Low Frequency ◽  
High Amplitude ◽  
Seismic Facies ◽  
Submarine Fan ◽  
North West ◽  
The North ◽  
Braided Channel ◽  
Low Amplitude

A possible submarine fan system of Valanginian age occurs in the south of the western half of Permit WA-212-P in the Browse Basin. Seismic mapping and interpretation have allowed the recognition of five seismic facies which are considered representative of this fan system.The five seismic facies are the upper-middle fan braided channel facies, the upper-middle fan braided interchannel facies, the lower fan channel facies, the lower fan sheet facies, and the lower fan lobe fringe facies. The reflections of the upper-middle braided channel fan facies are discontinuous, disrupted, convex up, low amplitude and high frequency. The interchannel facies has reflections that are concave up, continuous, low frequency and moderate to high amplitude. The lower fan channel facies are recognised by convex up, discontinuous, high frequency and low amplitude reflections. The lower fan sheet facies is noted by mounded configurations with continuous, moderate to high amplitude, moderate frequency reflections. The lower fan lobe fringe facies reflections are flat, often shingled reflections with moderate discontinuity, moderate to high amplitude and low to moderate frequency.Since no wells penetrate the submarine fan, the interpretation is based on seismic reflection configurations which are considered typical of submarine fan segments. The interpreted ancient submarine fan occurs on the basin floor adjacent to a probable ramp type margin, and manifests shape and setting consistent with known submarine fans, such as the Eocene Frigg Fan of the North Sea, and the Lower Cretaceous Barrow Group turbidites in the Carnarvon Basin.Seismic facies mapping, in conjunction with sequence stratigraphy concepts, is particularly useful in areas such as the Browse Basin where considerable marine shale sections exist with little structure, and sequences with reservoir potential continue to be a problem to locate. For instance, in Caswell-1, a well drilled in 1977 immediately north of the permit area, 200 barrels of oil flowed from thin sands within a shale sequence of Albian age. Results of this study indicate that local seismic reflection signatures may be indicative of potential sandstone reservoirs in the vicinity of the study area.

Epigenetic versus syngenetic magnetite as a cause of magnetic anomalies

Geophysics ◽  
1992 ◽  
Vol 57 (1) ◽  
pp. 60-68 ◽  
Author(s):  
S. Parker Gay
Keyword(s):  
Magnetic Susceptibility ◽  
High Frequency ◽  
Magnetic Anomalies ◽  
High Amplitude ◽  
Sulfide Mineral ◽  
Unconsolidated Sediments ◽  
Near Surface ◽  
Surface Magnetization ◽  
Ground Magnetic ◽  
Low Amplitude

Studies carried out a decade ago at Cement Field, Oklahoma, suggesting evidence of epigenetic (diagenetic) magnetite are shown to have been flawed for two reasons. Aeromagnetic surveying over the field could not have yielded the type of broad, low‐amplitude anomalies expected from hypothesized diagenetic magnetite sources because of the occurrence of numerous high‐amplitude magnetic spikes over cultural sources. Applied Geophysics, Inc., flew a low level (approximately 30 m above ground) aeromagnetic profile along the long axis of the field in 1983 and encountered nearly 40 such spikes due to culture. Additionally, studies of drill cuttings from 23 wells in the field showed them all to be contaminated by rust, scale, and bit shavings, in approximately the same percentages as had been postulated for diagenetic magnetite in 5 wells examined in the prior study. Subsequent studies in support of the diagenetic magnetite hypothesis in other areas have relied on the occurrence of “high‐wavenumber” (i.e., high‐frequency) aeromagnetic or ground magnetic anomalies as indicators of such magnetite. These studies do not take into account the possibility of detrital magnetite as the cause of the high‐frequency anomalies. Detrital magnetite is of near‐universal occurrence in small quantities in both unconsolidated sediments and sedimentary rocks and is easily concentrated by fluvial processes which would affect ground magnetic surveys in particular, but airborne surveys as well. In rocks of Mesozoic age or younger, detrital magnetite occurs in sufficient quantity in some areas to give quite detectable airborne magnetic anomalies. Four such localities have recently been documented, one in the Utah‐Idaho‐Wyoming USA thrust belt; and two in the western United States and one in Central America. However, recent measurements of soil magnetic susceptibility over oil fields do present intriguing evidence for anomalous near‐surface magnetization associated with hydrocarbon leakage plumes. Based on previous experience with sulfide mineral deposits, I postulate that small quantities of pyrite, and perhaps lesser quantities of other sulfide minerals that are sometimes precipitated by rising hydrocarbons, are oxidized above the water table in the vadose zone to secondary magnetic iron oxides. This thin layer of weak anomalous magnetization, when properly distinguished from magnetization due to detrital magnetite, would be recognizable with shallow magnetic susceptibility measurements, and possibly ground magnetic surveys, but probably not with airborne surveys, except under exceptional circumstances.

Speckle interferometric sensor to measure low-amplitude high frequency Ocular Microtremor (OMT)

2009 ◽  
Author(s):  
James P. Ryle ◽  
Mohammed Al-Kalbani ◽  
Unnikrishnan Gopinathan ◽  
Gerard Boyle ◽  
Davis Coakley ◽  
...  
Keyword(s):  
High Frequency ◽  
Interferometric Sensor ◽  
Low Amplitude ◽  
Ocular Microtremor

Development of the first urinary reproductive hormone ranges referenced to independently determined ovulation day

2015 ◽  
Vol 53 (7) ◽  
Author(s):  
Sarah Johnson ◽  
Sarah Weddell ◽  
Sonya Godbert ◽  
Guenter Freundl ◽  
Judith Roos ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Hormone Level ◽  
Ovarian Follicle ◽  
Reproductive Hormone ◽  
Fertility Status ◽  
Daily Urine ◽  
Follicle Size ◽  
Status Information ◽  
Progesterone Metabolite ◽  
Level Analysis

AbstractUrinary hormone level analysis provides valuable fertility status information; however, previous studies have not referenced levels to the ovulation day, or have used outdated methods. This study aimed to produce reproductive hormone ranges referenced to ovulation day determined by ultrasound.Women aged 18–40 years (no reported infertility) collected daily urine samples for one complete menstrual cycle. Urinary luteinising hormone (LH), estrone-3-glucuronide (E3G, an estradiol metabolite), follicle stimulating hormone (FSH) and pregnanediol-3-glucuronide (P3G, a progesterone metabolite) were measured using previously validated assays. Volunteers underwent trans-vaginal ultrasound every 2 days until the dominant ovarian follicle size reached 16 mm, when daily scans were performed until ovulation was observed. Data were analysed to create hormone ranges referenced to the day of objective ovulation as determined by ultrasound.In 40 volunteers, mean age 28.9 years, urinary LH surge always preceded ovulation with a mean of 0.81 days; thus LH is an excellent assay-independent predictor of ovulation. The timing of peak LH was assay-dependent and could be post-ovulatory; therefore should no longer be used to predict/determine ovulation. Urinary P3G rose from baseline after ovulation in all volunteers, peaking a median of 7.5 days following ovulation. Median urinary peak E3G and FSH levels occurred 0.5 days prior to ovulation. A persistent rise in urinary E3G was observed from approximately 3 days pre- until 5 days post-ovulation.This study provides reproductive hormone ranges referenced to the actual day of ovulation as determined by ultrasound, to facilitate examination of menstrual cycle endocrinology.

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