scholarly journals Frequent handling of grazing beef cattle maintained under the rotational stocking method improves temperament over time

2018 ◽  
Vol 58 (2) ◽  
pp. 307 ◽  
Author(s):  
Maria C. Ceballos ◽  
Karen Camille R. Góis ◽  
Aline C. Sant'Anna ◽  
Mateus J. R. Paranhos da Costa
Keyword(s):  
Beef Cattle ◽  
High Frequency ◽  
Low Frequency ◽  
Flight Speed ◽  
Grazing System ◽  
Grazing Period ◽  
Animal Handling ◽  
Over Time ◽  
Reactivity Score

Our aims were to assess the effects of handling frequency on temperament evolution in cattle kept under rotational stocking method (RSM), as well as to compare the temperament of animals maintained under rotational versus alternate stocking (ASM) methods. We evaluated 4256 males raised on pasture from four private properties (Farms 1–4), for a total of 9628 observations. The study was divided into two complementary approaches. In the first one, monthly visits were conducted at 35-day intervals to assess the cattle temperament (n = 1979) raised on grazing system using RSM, while, in the second approach, we evaluated the temperament of cattle (n = 3600) kept under two different stocking methods, namely, (1) RSM (n = 2007), characterised by a high frequency of animal handling and a 4-day grazing period, and (2) ASM (n = 1593), characterised by a low frequency of handling and a 20-day grazing period. Composite reactivity score (RS), and flight speed (FS) were considered as temperament indicators. Reductions of RS and FS means were observed during successive assessments under RSM. Significant effects of stocking method on FS (P < 0.05) and RS (P < 0.01) were found, with lower FS and RS means for animals under RSM than for those under ASM. In conclusion, the frequent handling in the rotational stocking method favoured the improvement of cattle temperament over time, with lower levels of reactivity among cattle raised under this stocking method than with animals raised under the alternate stocking method.

Naturalistic Study of the use of Transcranial Magnetic Stimulation in the Treatment of Depressive Relapse

2006 ◽  
Vol 40 (9) ◽  
pp. 764-768 ◽  
Author(s):  
Paul B. Fitzgerald ◽  
Jessica Benitez ◽  
Anthony R. De Castella ◽  
Timothy L. Brown ◽  
Z. Jeff Daskalakis ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
High Frequency ◽  
Magnetic Stimulation ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Low Frequency ◽  
Naturalistic Study ◽  
Treatment Of Depression ◽  
Long Term Impact ◽  
Over Time

Background: The efficacy of repetitive transcranial magnetic stimulation (rTMS) in the treatment of depression has been assessed in a number of acute treatment trials during the last 10 years. Little is known about the long-term impact of the treatment on the disorder and its effectiveness when applied for repeated relapses of depression over time. Method: Nineteen patients who had previously responded to rTMS in clinical trials received treatment with rTMS for a total of 30 episodes of depressive relapse. Results: Approximately 10 months elapsed between treatment episodes. The majority of patients achieved a significant improvement in each treatment course with significant improvements achieved in patients treated with both low-frequency right-sided rTMS and high-frequency left-sided rTMS. Conclusions: The study suggests that rTMS may have value in the treatment of episodes of depressive relapse with little reduction in efficacy over time.

scholarly journals Memory resources recover gradually over time: The effects of word-frequency, presentation rate and list-composition on binding errors and mnemonic precision in source memory

2019 ◽  
Author(s):  
Vencislav Popov ◽  
Matthew So ◽  
Lynne Reder
Keyword(s):  
Word Frequency ◽  
High Frequency ◽  
Continuous Distribution ◽  
Low Frequency ◽  
Presentation Rate ◽  
Frequency Effect ◽  
Word Frequency Effect ◽  
Reproduction Task ◽  
Memory Precision ◽  
Over Time

Normative word frequency has played a key role in the study of human memory, but there is little agreement as to the mechanism responsible for its effects. To determine whether word frequency affects binding probability or memory precision, we used a continuous reproduction task to examine working memory for spatial positions of words. In three experiments, after studying a list of five words, participants had to report the spatial location of one of them on a circle. Across experiments we varied word frequency, presentation rate and the proportion of low frequency words on each trial. A mixture model dissociated memory precision, binding failure and guessing rate parameters from the continuous distribution of errors. On trials that contained only low- or only high-frequency words, low-frequency words lead to a greater degree of error in recalling the associated location. This was due to a higher word-location binding failure and not due to differences in memory precision or guessing rates. Slowing down the presentation rate eliminated the word frequency effect by reducing binding failures for low-frequency words. Mixing frequencies in a single trial hurt high-frequency and helped low-frequency words. These findings support the idea that word frequency can lead to both positive and negative mnemonic effects depending on a trade-off between a HF encoding advantage and a LF retrieval cue advantage. We suggest that 1) low-frequency words require more resources for binding, 2) that these resources recover gradually over time, and that 3) binding fails when these resources are insufficient.

scholarly journals Beauty and Ugliness of Aggregation over Time: A Survey

2017 ◽  
Vol 68 (3) ◽  
Author(s):  
Nlandu Mamingi
Keyword(s):  
Public Policy ◽  
Time Series ◽  
High Frequency ◽  
Low Frequency ◽  
High Frequency Data ◽  
Frequency Data ◽  
Economic Time Series ◽  
Negative Effects ◽  
Economic Time ◽  
Over Time

AbstractThis paper delivers an up-to-date literature review dealing with aggregation over time of economic time series, e.g. the transformation of high-frequency data to low frequency data, with a focus on its benefits (the beauty) and its costs (the ugliness). While there are some benefits associated with aggregating data over time, the negative effects are numerous. Aggregation over time is shown to have implications for inferences, public policy and forecasting.

scholarly journals BEEF PRODUCTION FROM LUCERNE AND LUCERNE/PRAIRIE GRASS SWARDS ON THE PUMICE SOILS OF THE TAUPO REGION

1977 ◽  
pp. 53-60
Author(s):  
K. Marsh ◽  
L.F.C. Brunswick
Keyword(s):  
Beef Cattle ◽  
Significant Interaction ◽  
Animal Production ◽  
Stocking Rate ◽  
Beef Production ◽  
Rotational Grazing ◽  
Grazing System ◽  
Prairie Grass ◽  
Grazing Period ◽  
Stocking Rates

Lucerne and lucerne/prairie grass swards were compared at three stocking rates using yearling beef cattle. A 35 day rotational grazing system was used and the experiment ran for 130 days from early October, 1976. Pasture DM yields were higher on the mixed sward but animal production was greater on the lucerne only sward, particularly from December onwards. Increasing stocking rate tended to reduce herbage DM yield and per-animal production. There was no significant interaction between sward type and stocking rate on either sward or animal yield. Lucerne and lucerne/ prairie grass swards on pumice soil compared favourably with fertile Waikato permanent pastures in terms of carcass gain per hectare over the grazing period.

scholarly journals Low-Intensity, High-Frequency Grazing Strategy Increases Herbage Production and Beef Cattle Performance on Sorghum Pastures

Animals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 13
Author(s):  
Thales Baggio Portugal ◽  
Leonardo Silvestri Szymczak ◽  
Anibal de Moraes ◽  
Lidiane Fonseca ◽  
Jean Carlos Mezzalira ◽  
...  
Keyword(s):  
Beef Cattle ◽  
High Frequency ◽  
Management Strategy ◽  
Average Daily Gain ◽  
Low Frequency ◽  
Live Weight ◽  
Grazing Management ◽  
Intake Rate ◽  
Low Intensity ◽  
Herbage Intake

We assessed the effects of high-intensity and low-frequency (HILF) vs. low-intensity and high-frequency (LIHF) grazing on herbage production and performance of beef cattle grazing sorghum pastures. The experimental design was a complete randomized block with two treatments and four replicates (paddocks), carried out in 2014/15. The management target of 50 and 30 cm for pre- and post-grazing, respectively, a LIHF grazing management strategy oriented to maximize beef cattle herbage intake per unit time, was compared with a HILF grazing management strategy of 80 and 20 cm for pre- and post-grazing, respectively, aiming to maximize herbage accumulation and harvest efficiency. Sixteen Brangus steers of 15-month-old and 265 ± 21 kg of live weight (LW) were randomly distributed to paddocks (experimental units). The LIHF resulted in shorter rest periods when compared with the HILF. The greater leaf lamina mass in LIHF allowed greater sward light interception at post-grazing, resulting in greater total herbage production than HILF (7581 and 4154 kg DM/ha, respectively). The average daily gain (ADG) of steers was greater for the LIHF than for the HILF treatment (0.950 and 0.702 kg/animal, respectively); however, even with a greater stocking rate in the HILF, there was no difference for LW gain per ha, with an average of 4 kg LW/ha/day. Our findings demonstrated that the LIHF strategy that is based on offering to the animals an optimal sward structure to favor the maximum herbage intake rate fosters greater herbage production, harvesting efficiency, and ADG without compromising LW gain per area of beef steers, despite the lower herbage harvested per stocking cycle.

scholarly journals ANALYSIS OF HIGH FREQUENCY BREAKING WAVES AND LOW FREQUENCY SURGES GENERATED IN HARBORS DUE TO PASSAGE OF DEEP-DRAFT TANKERS

2018 ◽  
pp. 27
Author(s):  
Arpit Agarwal ◽  
Scott Fenical ◽  
Kirsten McElhinney ◽  
Paul Carangelo ◽  
David Krams
Keyword(s):  
High Frequency ◽  
Pressure Field ◽  
Low Frequency ◽  
Breaking Waves ◽  
Wave Activity ◽  
The West ◽  
Ship Traffic ◽  
Corpus Christi ◽  
Navigation Channel ◽  
Over Time

Cline’s Point Marina, located in Port Aransas, TX, has been experiencing detrimental conditions near the marina’s entrance and within the marina itself during the passage of deep-draft ship traffic. The wave activity is primarily generated by pressure field effects from large, laden outbound vessels in Corpus Christi Ship Channel (CCSC). The basin was originally protected by an approximately 180 ft. long breakwater constructed in 1976 on the west side of the entrance which by 1980 has deteriorated and partially failed to 120 ft. long breakwater and continued deteriorating over time, reaching its approximate 60 ft. long current condition by 2003. The deterioration of this breakwater has reportedly resulted in enhanced penetration of deep-draft vessel wave activity into the marina (Figure 1). Mott MacDonald (MM) evaluated the mechanisms by which waves are generated in the navigation channel, transform, and enter the harbor, quantified the level of protection afforded by past and present entrance breakwater configuration(s), and developed conceptual alternatives for improving conditions inside the marina.

Heart Rate Variability in Premature Infants During Feeding

2007 ◽  
Vol 8 (4) ◽  
pp. 283-293 ◽  
Author(s):  
Lisa Brown
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Feeding Behavior ◽  
Infant Feeding ◽  
Premature Infants ◽  
High Frequency ◽  
Low Frequency ◽  
Research Attention ◽  
Physiologic Regulation ◽  
Over Time

Early mother-infant interaction, a potentially major contributor to the development of a premature infant's behavioral and physiologic regulation, has received very little research attention. This study examined the development of physiologic regulation in relation to maternal-infant feeding interaction for 43 premature infants, from the time caregiving responsibility was transferred to the mother through each infant's 4th postterm month. Infants and mothers were seen in a special care nursery just before discharge and in home at 1 and 4 months postterm age. General linear mixed models were used to examine the changes in infant heart rate variability (HRV) and Positive Affective Involvement and Sensitivity/Responsiveness scores over time and infant HRV over feeding conditions (prefeeding, feeding, and postfeeding). Significant differences were found for high-frequency and low-frequency HRV over time (p < .001 and p = .014, respectively). However, maternal feeding behavior did not show a significant effect of time (p = .24). The feeding condition effect on high-frequency HRV was significant (p < .001), with HRV lower during feeding compared to both prefeeding and postfeeding. Maternal feeding behavior was not associated with infant HRV. Discovering the ways in which maternal feeding behavior contributes to infant physiologic regulation may require study of the relationship of HRV to infant feeding behavior.

Simulations of high-resolution images of amorphous silicon films

1986 ◽  
Vol 44 ◽  
pp. 544-545
Author(s):  
G. Y. Fan ◽  
J. M. Cowley
Keyword(s):  
Electron Microscope ◽  
High Frequency ◽  
Fourier Transformation ◽  
Amorphous Materials ◽  
Low Frequency ◽  
Chromatic Aberration ◽  
Structure Information ◽  
Frequency Components ◽  
High Resolution Images ◽  
Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

SEM image sharpness analysis

1996 ◽  
Vol 54 ◽  
pp. 142-143
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Quantitative Information ◽  
Primary Electron ◽  
Image Sharpness ◽  
Critical Dimensions ◽  
Sem Image ◽  
Frequency Changes ◽  
Electron Microscopes ◽  
Scanning Electron

Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or better) at 1.0 kV accelerating voltage for the measurement of nominal 0.25-0.35 micrometer semiconductor critical dimensions. Testing and proving that the instrument is performing at this level on a day-by-day basis is an industry need and concern which has been the object of a study at NIST and the fundamentals and results are discussed in this paper.In scanning electron microscopy, two of the most important instrument parameters are the size and shape of the primary electron beam and any image taken in a scanning electron microscope is the result of the sample and electron probe interaction. The low frequency changes in the video signal, collected from the sample, contains information about the larger features and the high frequency changes carry information of finer details. The sharper the image, the larger the number of high frequency components making up that image. Fast Fourier Transform (FFT) analysis of an SEM image can be employed to provide qualitiative and ultimately quantitative information regarding the SEM image quality.

Real Ear Sound Pressure Levels Developed by Three Portable Stereo System Earphones

1992 ◽  
Vol 1 (4) ◽  
pp. 52-55 ◽  
Author(s):  
Gail L. MacLean ◽  
Andrew Stuart ◽  
Robert Stenstrom
Keyword(s):  
High Frequency ◽  
Sound Pressure ◽  
Low Frequency ◽  
Test System ◽  
Output Frequency ◽  
Frequency Effects ◽  
Adult Men ◽  
Frequency Responses ◽  
Significant Difference ◽  
Sound Pressure Levels

Differences in real ear sound pressure levels (SPLs) with three portable stereo system (PSS) earphones (supraaural [Sony Model MDR-44], semiaural [Sony Model MDR-A15L], and insert [Sony Model MDR-E225]) were investigated. Twelve adult men served as subjects. Frequency response, high frequency average (HFA) output, peak output, peak output frequency, and overall RMS output for each PSS earphone were obtained with a probe tube microphone system (Fonix 6500 Hearing Aid Test System). Results indicated a significant difference in mean RMS outputs with nonsignificant differences in mean HFA outputs, peak outputs, and peak output frequencies among PSS earphones. Differences in mean overall RMS outputs were attributed to differences in low-frequency effects that were observed among the frequency responses of the three PSS earphones. It is suggested that one cannot assume equivalent real ear SPLs, with equivalent inputs, among different styles of PSS earphones.

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