PSII-2 Daily patterns for respiration rates and internal temperatures of heat stressed lactating sows with or without electronically controlled cooling pads

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 321-321
Author(s):  
Jason R Graham ◽  
Michaiah J Galvin ◽  
Taylor L Jansen ◽  
Tyler C Field ◽  
Robert M Stwalley ◽  
...  
Keyword(s):  
Single Phase ◽  
Mixed Model ◽  
Random Effect ◽  
Regression Equations ◽  
Controlled Cooling ◽  
Study Objective ◽  
Final Model ◽  
Lactating Sows ◽  
Periodic Regression ◽  
The Impact

Abstract Lactating sows are especially sensitive to heat stress (HS) due to high metabolic demands resulting from milk output. Therefore, there is a need to develop effective cooling technologies that reduce the impact of HS on lactating sows. The study objective was to determine whether electronically controlled cooling pads (ECP) would allow sows to remain euthermic under HS conditions. Twelve multiparous (2.69 ± 0.85) lactating sows (265.4 ± 26.1 kg) and litters (11.4 ± 0.7 piglets/litter) were assigned to either a non-functional ECP (NECP; n = 6) or an ECP (n = 6), housed in farrowing crates, and tested over two repetitions. Sows were provided feed and water ad libitum and all sows were exposed to HS (28.27 ± 1.42°C nighttime to 35.14 ± 0.70°C daytime). Body temperature (TB), was measured hourly using vaginal implants, and respiration rate (RR) was measured in 30 min intervals from 0600 to 2100 hrs over 2 d representing mid- and late lactation. Mixed model periodic regression equations were fitted to the TB and RR to time. The final model for TB included the effect of replicate, random effect of sow, day of lactation as a covariate, single-phase sine and cosine variables for each treatment and 2-phase sine and cosine periodic regression variables. The final model for RR included the random effect of sow, effect of treatment, replicate, day of lactation, sleeping, and single-phase sine and cosine functions for each treatment. An interaction (P < 0.05) between treatment and sine or cosine was observed for TB. For RR there was no interaction for treatment and cosine (P = 0.07), but an interaction (P < 0.05; -9.94) was observed for sine. The significant treatment by wavelength interactions observed indicate a change in RR and TB patterns when sows are placed on ECPs.

scholarly journals The Impact of Misspecified Random Effect Distribution in a Weibull Regression Mixed Model

Stats ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 48-76
Author(s):  
Freddy Hernández ◽  
Viviana Giampaoli
Keyword(s):  
Weibull Distribution ◽  
Random Effects ◽  
Mixed Models ◽  
Fixed Effects ◽  
Mixed Model ◽  
Random Effect ◽  
Estimation Procedure ◽  
Weibull Regression ◽  
Two Parameters ◽  
The Impact

Mixed models are useful tools for analyzing clustered and longitudinal data. These models assume that random effects are normally distributed. However, this may be unrealistic or restrictive when representing information of the data. Several papers have been published to quantify the impacts of misspecification of the shape of the random effects in mixed models. Notably, these studies primarily concentrated their efforts on models with response variables that have normal, logistic and Poisson distributions, and the results were not conclusive. As such, we investigated the misspecification of the shape of the random effects in a Weibull regression mixed model with random intercepts in the two parameters of the Weibull distribution. Through an extensive simulation study considering six random effect distributions and assuming normality for the random effects in the estimation procedure, we found an impact of misspecification on the estimations of the fixed effects associated with the second parameter σ of the Weibull distribution. Additionally, the variance components of the model were also affected by the misspecification.

scholarly journals Bivariate Random Effects Meta-Analysis of Diagnostic Studies Using Generalized Linear Mixed Models

2009 ◽  
Vol 30 (4) ◽  
pp. 499-508 ◽  
Author(s):  
Haitao Chu ◽  
Hongfei Guo ◽  
Yijie Zhou
Keyword(s):  
Sensitivity And Specificity ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Random Effect ◽  
Point Estimation ◽  
Test Accuracy ◽  
Logit Transformation ◽  
Link Functions ◽  
Special Cases ◽  
The Impact

Bivariate random effect models are currently one of the main methods recommended to synthesize diagnostic test accuracy studies. However, only the logit transformation on sensitivity and specificity has been previously considered in the literature. In this article, the authors consider a bivariate generalized linear mixed model to jointly model the sensitivities and specificities, and they discuss the estimation of the summary receiver operating characteristic curve (ROC) and the area under the ROC curve (AUC). As the special cases of this model, the authors discuss the commonly used logit, probit, and complementary log-log transformations. To evaluate the impact of misspecification of the link functions on the estimation, they present 2 case studies and a set of simulation studies. Their study suggests that point estimation of the median sensitivity and specificity and AUC is relatively robust to the misspecification of the link functions. However, the misspecification of link functions has a noticeable impact on the standard error estimation and the 95% confidence interval coverage, which emphasizes the importance of choosing an appropriate link function to make statistical inference.

PSII-6 Electronically controlled cooling pads improve litter growth and thermoregulatory measures and increase total heat production in heat stressed lactating sows

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 312-312
Author(s):  
Taylor L Jansen ◽  
Michaiah J Galvin ◽  
Tyler C Field ◽  
Jason R Graham ◽  
Robert M Stwalley ◽  
...  
Keyword(s):  
Heat Stress ◽  
Growth Performance ◽  
Heat Production ◽  
Total Heat ◽  
Metabolic Heat Production ◽  
Controlled Cooling ◽  
Study Objective ◽  
Metabolic Heat ◽  
Indirect Measures ◽  
Lactating Sows

Abstract Heat stress (HS) decreases lactation output in sows due to an attempt to reduce metabolic heat production; however, this negatively affects litter growth performance. Therefore, the study objective was to determine whether electronically controlled cooling pads (ECP) would improve indirect measures of lactation output (e.g., metabolic heat production) and litter growth performance in HS exposed sows. Over two repetitions, 12 multiparous (2.69 ± 0.85) lactating sows (265.4 ± 26.1 kg) and litters were assigned to either an ECP (n = 6) or a non-functional ECP (NECP; n = 6) and placed into farrowing crates within indirect calorimeters from d 3.7 ± 0.5 to d 18.7 ± 0.5 of lactation. Litters were standardized across all sows (11.4 ± 0.7 piglets/litter), and sows were provided ad libitum feed and water. All sows were exposed to cyclical HS (28.27 ± 1.42°C nighttime to 35.14 ± 0.70°C daytime). On d 4, 8, 14, and 18 of lactation, indirect calorimetry was performed on each individual sow and litter to determine total heat production (THP). Body temperature (TB), was measured hourly using vaginal implants, and respiration rate (RR) was measured daily at 0700, 1100, 1300, 1500, and 1900 h. Litter weights were obtained at birth and weaning. An overall decrease (P < 0.01; 25 bpm) in RR and maximum daily TB (P = 0.02; 0.40°C) was observed in ECP versus NECP sows. An increase in THP (P < 0.01; 20.4%) and THP/kg0.75 (P < 0.01; 23.1%) was observed for ECP when compared to NECP sows and litters. Litter growth rate was increased (P < 0.01; 20.8%) in ECP versus NECP sows. In summary, the use of ECP improves litter growth, thermoregulatory measures, and bioenergetic parameters associated with greater milk production in lactating sows exposed to cyclical heat stress.

scholarly journals 46 Novel creep area heat source impact on pre-wean mortality occurrence

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 34-35
Author(s):  
Benjamin Smith ◽  
Brett Ramirez ◽  
Laura L Greiner
Keyword(s):  
Heat Source ◽  
Fixed Effects ◽  
Mixed Model ◽  
Random Effect ◽  
Experimental Unit ◽  
Mortality Data ◽  
Accounting System ◽  
Swine Industry ◽  
Data Set ◽  
The Impact

Abstract Pre-wean mortality (PWM) is a multifaceted problem facing the US swine industry. The objective of this study was to compare the occurrence of mortality and age of piglets between a novel heat source (HS; semi-enclosed heated microclimate; SEHM) and a conventional heat lamp setup. This study was conducted in two rooms at a 1,000 head commercial sow farm. Treatments were blocked by sow parity group (SPG; young, prime, and geriatric) over six farrowing cycles. Litters were cross fostered within HS treatment at 1 day of age. PWM, was the experimental unit, data were collected from the farm’s farrowing records and production accounting system. Age of the mortalities was categorized into four phases of lactation (PL) over the 20 d lactation (d0 to d3, d4 to d7, d8 to d11, and d12 to d20). Overall, there were 220 recorded instances of mortality. Data were analyzed in a CRBD using a PROC MIXED model in SAS (v9.4, SAS Inst., Cary, NC) and reported as LSMEANS with standard errors. The model included farrowing cycle as a random effect and the following fixed effects: HS, SPG, PL, HS*SPG, and HS*PL. Overall average PWM was 8.60%±0.80 for SEHM and 10.0%±0.70 for the heat lamps. There was no effect (P >0.05) of HS or HS*PL on PWM occurrence. There were significant effects of SPG (P=0.026), PL (P=0.05), and HS*SPG (P=0.036) on PWM occurrence. These data suggest that the HS type did not have an impact on the mortality rate or the timing of the mortality, indicating the mortalities that occurred had no relationship to HS. A limitation of this data set is the low sample size, thereby limiting the detection ability for this interaction. Further research into the impact of the HS is needed to expand the data set and to explore other popular HS effects on PWM.

scholarly journals Electronically controlled cooling pads can improve litter growth performance and indirect measures of milk production in heat-stressed lactating sows

2021 ◽  
Author(s):  
Jay S Johnson ◽  
Taylor L Jansen ◽  
Michaiah Galvin ◽  
Tyler C Field ◽  
Jason R Graham ◽  
...  
Keyword(s):  
Growth Performance ◽  
Milk Production ◽  
Heat Production ◽  
Average Daily Gain ◽  
Experimental Unit ◽  
Controlled Cooling ◽  
Study Objective ◽  
Indirect Measures ◽  
Lactating Sows ◽  
Daily Gain

Abstract Heat stress (HS) decreases lactation output in sows due to an attempt to reduce metabolic heat production. However, this negatively affects litter growth performance. Therefore, the study objective was to determine whether electronically controlled cooling pads (ECP) would improve indirect measures of lactation output (e.g., total heat production; THP) and litter growth performance in HS exposed sows. Over two repetitions, 12 multiparous (2.69 ± 0.85) lactating sows [265.4 ± 26.1 kg body weight (BW)] and litters were assigned to either an ECP (n = 3/repetition) or a non-functional ECP (NECP; n = 3/repetition) and placed into farrowing crates within indirect calorimeters from d 3.7 ± 0.5 to d 18.7 ± 0.5 of lactation. Litters were standardized across all sows (11.4 ± 0.7 piglets/litter), and sows were provided ad libitum feed and water. All sows were exposed to cyclical HS (28.27 ± 0.26°C nighttime to 33.09 ± 0.19°C daytime). On d 4, 8, 14, and 18 of lactation, indirect calorimetry was performed on each individual sow and litter to determine THP and THP/kg BW 0.75. Body temperature (TB) was measured hourly using vaginal implants, and respiration rate [RR; breaths per minute (bpm)] was measured daily at 0700, 1100, 1300, 1500, and 1900 hrs. Sow feed intake (FI) was assessed daily. Litter weights were obtained at birth, on d 4, 8, 14, and 18 of lactation, and at weaning. Data were analyzed using PROC GLIMMIX with sow and/or litter as the experimental unit. An overall decrease (P < 0.01; 25 bpm) in RR and maximum daily TB (P = 0.02; 0.40°C) was observed in ECP versus NECP sows. An increase in THP (P < 0.01; 20.4%) and THP/kg BW 0.75 (P < 0.01; 23.1%) was observed for ECP when compared to NECP sows and litters. Litter average daily gain and weaning weight was increased (P < 0.05; 25.0 and 19.2%, respectively) for ECP versus NECP litters. No FI differences were observed (P = 0.40) when comparing ECP (5.66 ± 0.31 kg/d) and NECP (5.28 ± 0.31 kg/d) sows. In summary, ECPs improve litter growth, thermoregulatory measures, and bioenergetic parameters associated with greater milk production in lactating sows exposed to cyclical HS.

scholarly journals 56 Impact of Electronically-Controlled Cooling Pads on Physiological Signs of Heat Stress in Early Lactation Sows

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 152-153
Author(s):  
Flannery J Whitmore ◽  
Allan P Schinckel ◽  
Robert Stwalley ◽  
Tyler Field ◽  
Morgan Burgett ◽  
...  
Keyword(s):  
Heat Stress ◽  
Feed Intake ◽  
Day Treatment ◽  
Time Of Day ◽  
Early Lactation ◽  
Controlled Cooling ◽  
Study Objective ◽  
Time Parity ◽  
The Difference ◽  
The Impact

Abstract The study objective was to evaluate the impact of electronically controlled cooling pads on physiological measurements of heat stress during early lactation. Twelve sows (d 3 to 11 of lactation) were provided with a specially designed cooling pad. Sows randomly received no cooling (CONTROL, n=6) or pads set to flush 2L cool water every 30s when aluminum plate reached 29.5°C (TREAT, n=6). Respiration rates (RR), rectal temperatures (RT) and skin temperatures (ST, 15 cm posterior to the ear) were recorded daily (0700 and 1500 h) for seven days of early lactation. Feed intake (DFI) was measured daily at 0700 h. RR, RT, and ST were fitted to a model that included the effects of day, time, parity, cooling pad treatment, and interactions. DFI was fitted to the same model, excluding time of day. For RR: treatment, day, time, treatment by day, treatment by time, and day by time interactions were significant (P< 0.0004, CONTROL=49, TREAT= 30). Pad treatment had greater impact on RR during the first two days of the trial when the temperature was greater (32°C maximum CONTROL mean=66 vs. TREAT mean=30) than the following five days: 42, and 30 respectively). There was greater treatment impact on RR at 1500 versus 0700 h (0700 h: CONTROL= 35, TREAT= 25; 1500 h: CONTROL= 61, TREAT= 36). For RT: treatment, day, time, parity and interaction of day by time were significant (P< 0.01, CONTROL= 37, treat= 35.). For ST: treatment, day, time, parity and the interactions of time by parity, treatment by time, and day by time were significant (P< 0.0006, mean CONTROL=36.5, TREAT= 35.1). For DFI: day and the interaction of day by treatment were significant. The difference in feed intake between treatments increased as day increased. The use of electronically controlled cooling pads reduced measures of heat stress in early lactating sows.

scholarly journals Impact of thermoelectric cooling modules on the efficiency of a single-phase asynchronous machine

2014 ◽  
Vol 25 (1) ◽  
pp. 13-18
Author(s):  
Rupert Gouws ◽  
Heino Van Jaarsveldt
Keyword(s):  
Single Phase ◽  
Parameter Analysis ◽  
Circuit Parameter ◽  
Thermoelectric Cooling ◽  
Controlled Cooling ◽  
Asynchronous Machine ◽  
Temperature Environment ◽  
Lower Temperature ◽  
The Impact ◽  
Equivalent Circuit Parameter

In this paper, the authors present the impact of thermoelectric cooling modules (TECMs) on the efficiency of a single-phase asynchronous machine. TECMs are used to lower the stator winding temperature and core temperature of the single-phase asynchronous machine. A similar effect might be possible by operating the asynchronous machine in a controlled lower temperature environment or by using other means of improved controlled cooling. An overview on the materials and method used during the experimental setup of the single-phase asynchronous machine with the TECMs is provided. Experimental results on the efficiency analysis, temperature analysis and equivalent circuit parameter analysis are provided. It is shown that the efficiency of the single-phase asynchronous machine can be increased by 4.44% when cooled by TECMs.

THE MODEL FOR MANAGING INVESTMENTS IN THE MOSCOW ENVIRONMENT BASED ON A POWER REGRESSION EQUATION

2020 ◽  
Vol 2 (7) ◽  
pp. 91-99
Author(s):  
E. V. KOSTYRIN ◽  
◽  
M. S. SINODSKAYA ◽  
Keyword(s):  
Solid Waste ◽  
Influencing Factors ◽  
Pair Correlation ◽  
Approximation Error ◽  
Regression Equation ◽  
Regression Equations ◽  
The Impact ◽  
The Relationship ◽  
Average Approximation ◽  
Average Approximation Error

The article analyzes the impact of certain factors on the volume of investments in the environment. Regression equations describing the relationship between the volume of investment in the environment and each of the influencing factors are constructed, the coefficients of the Pearson pair correlation between the dependent variable and the influencing factors, as well as pairwise between the influencing factors, are calculated. The average approximation error for each regression equation is determined. A correlation matrix is constructed and a conclusion is made. The developed econometric model is implemented in the program of separate collection of municipal solid waste (MSW) in Moscow. The efficiency of the model of investment management in the environment is evaluated on the example of the growth of planned investments in the activities of companies specializing in the export and processing of solid waste.

Investigating the Impact of Cognitive Training for Individuals With Bothersome Tinnitus: A Randomized Controlled Trial

2021 ◽  
pp. 019459982199474
Author(s):  
Maggie Xing ◽  
Dorina Kallogjeri ◽  
Jay F. Piccirillo
Keyword(s):  
Randomized Controlled Trial ◽  
Cognitive Training ◽  
Mixed Model ◽  
Controlled Trial ◽  
Intervention Group ◽  
Control Group ◽  
Functional Index ◽  
Open Label ◽  
Randomized Controlled ◽  
The Impact

Objective To evaluate the effectiveness of cognitive training in improving tinnitus bother and to identify predictors of patient response. Study Design Prospective open-label randomized controlled trial. Setting Online. Methods Participants were adults with subjective idiopathic nonpulsatile tinnitus causing significant tinnitus-related distress. The intervention group trained by using auditory-intensive exercises for 20 minutes per day, 5 days per week, for 8 weeks. The active control group trained on the same schedule with non–auditory intensive games. Surveys were completed at baseline, 8 weeks, and 12 weeks. Results A total of 64 participants completed the study. The median age was 63 years (range, 25-69) in the intervention group and 61 years (34-68) in the control group. Mixed model analysis revealed that within-subject change in Tinnitus Functional Index in the intervention group was not different than the control group, with marginal mean differences (95% CI): 0.24 (–11.20 to 10.7) and 2.17 (–8.50 to 12.83) at 8 weeks and 2.33 (–8.6 to 13.3) and 3.36 (–7.91 to 14.6) at 12 weeks, respectively. When the 2 study groups were compared, the control group had higher Tinnitus Functional Index scores than the intervention group by 10.5 points at baseline (95% CI, –0.92 to 29.89), 8.1 at 8 weeks (95% CI, –3.27 to 19.42), and 9.4 at 12 weeks (95% CI, –2.45 to 21.34). Conclusion Auditory-intensive cognitive training was not associated with changes in self-reported tinnitus bother. Given the potential for neuroplasticity to affect tinnitus, we believe that future studies on cognitive training for tinnitus remain relevant.

scholarly journals The generalizability crisis

2020 ◽  
pp. 1-37
Author(s):  
Tal Yarkoni
Keyword(s):  
Quantitative Analysis ◽  
Statistical Inference ◽  
Random Effects ◽  
False Positive ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Random Effect ◽  
Statistical Procedures ◽  
Subject Variability ◽  
Replication Crisis

Abstract Most theories and hypotheses in psychology are verbal in nature, yet their evaluation overwhelmingly relies on inferential statistical procedures. The validity of the move from qualitative to quantitative analysis depends on the verbal and statistical expressions of a hypothesis being closely aligned—that is, that the two must refer to roughly the same set of hypothetical observations. Here I argue that many applications of statistical inference in psychology fail to meet this basic condition. Focusing on the most widely used class of model in psychology—the linear mixed model—I explore the consequences of failing to statistically operationalize verbal hypotheses in a way that respects researchers' actual generalization intentions. I demonstrate that whereas the "random effect" formalism is used pervasively in psychology to model inter-subject variability, few researchers accord the same treatment to other variables they clearly intend to generalize over (e.g., stimuli, tasks, or research sites). The under-specification of random effects imposes far stronger constraints on the generalizability of results than most researchers appreciate. Ignoring these constraints can dramatically inflate false positive rates, and often leads researchers to draw sweeping verbal generalizations that lack a meaningful connection to the statistical quantities they are putatively based on. I argue that failure to take the alignment between verbal and statistical expressions seriously lies at the heart of many of psychology's ongoing problems (e.g., the replication crisis), and conclude with a discussion of several potential avenues for improvement.

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