Response Plateau Research Articles

Dynamic and creep and recovery performance of Fe3O4 nanoparticle and carbonyl iron microparticle water-based magnetorheological fluid

This study investigates dynamic mechanical properties and creep and recovery behaviors of disc-shaped magnetic Fe3O4 nanoparticles with carbonyl iron (CI) flake-shaped microparticles in water-based MR fluid. The experimental study is performed using a parallel plate rheometer. Dynamic performance and creep and recovery behaviors help understand deformation mechanism for its practical applications in MR devices like seismic vibration control, active dampers, earthquake dampers, etc., under applied strain, and stress levels. The oscillatory experiment reveals a transition from viscoelastic-to-viscous behavior at the critical strain of 0.1%. The storage modulus [Formula: see text] of CI/Fe3O4 MR fluid showed a stable plateau region over the small strain area and storage modulus [Formula: see text] independent of strain amplitude. The frequency experiment demonstrated that storage moduli [Formula: see text] exhibit elastic response and stable plateau region over the complete external frequency range, suggesting the distinguished solid-like behavior of the MR fluid. Creep and recovery experiments showed that fluid acts as a linear viscoelastic material at lower stress levels. As the stress levels increase, the contribution of retardation strain and viscous strain decreases, and it acts like nonlinear viscoelastic material. In summary, this work is expected to obtain MR fluid results for application in MR devices under applied strain, frequencies, and constant stress levels.

Factors affecting performance response of pigs exposed to different challenge models: a multivariate approach.

Factors associated with the severity with which different challenge models (CMs) compromise growth performance in pigs were investigated using hierarchical clustering on principal components (HCPC) analysis. One hundred seventy-eight studies reporting growth performance variables (average daily gain [ADG], average daily feed intake [ADFI], gain:feed [GF], and final body weight [FBW]) of a Control (Ct) vs. a Challenged (Ch) group of pigs using different CMs (enteric [ENT], environmental [ENV], lipopolysaccharide [LPS], respiratory [RES], or sanitary condition [SAN] challenges) were included. Studies were grouped by similarity in performance in three clusters (C1, C2, and C3) by HCPC. The effects of CM, cluster, and sex (males [M], females [F], mixed [Mi]) were investigated. Linear (LRP) and quadratic (QRP) response plateau models were fitted to assess the interrelationships between the change in ADG (∆ADG) and ADFI (∆ADFI) and the duration of challenge. All variables increased from C1 through C3, except for GF, which decreased (P < 0.05). LPS was more detrimental to ADG than ENV, RES, and SAN models (P < 0.05). Furthermore, LPS also lowered GF more than all the other CMs (P < 0.05). The ∆ADG independent of ∆ADFI was significant in LPS and SAN (P < 0.05), showed a trend toward the significance in ENT and RES (P < 0.10), and was not significant in ENV (P > 0.10), while the ∆ADG dependent on ∆ADFI was significant in ENT, ENV, and LPS only (P < 0.05). The critical value of ∆ADFI influencing the ∆ADG was significant in pigs belonging to C1 (P < 0.05) but not C2 or C3 (P > 0.10). The ∆ADG independent of duration post-Ch (irreparable portion of growth) was significant in C1 and C2 pigs, whereas the ∆ADFI independent of duration post-Ch (irreparable portion of feed intake) was significant in C1 pigs only (P < 0.05). Moreover, the time for recovery of ADG and ADFI after Ch was significant in pigs belonging to C1 and C2 (P < 0.05). Control F showed reduced ADG compared with Ct-M, and Ch-F showed reduced ADFI compared with Ch-M (P < 0.05). Moreover, the irreparable portion of ΔADG was 4.8 higher in F (-187.7; P < 0.05) compared with M (-39.1; P < 0.05). There are significant differences in growth performance response to CM based on cluster and sex. Furthermore, bacterial lipopolysaccharide appears to be an appropriate noninfectious model for immune stimulation and growth impairment in pigs.

Various far-field hydrological responses during 2015 Gorkha earthquake at two distant wells

Aquifer hydraulic parameter can change during earthquakes. Continuous monitoring of the response of water level to seismic waves or solid Earth tides provides an opportunity to document how earthquakes influence hydrological properties. Here, we use data of two groundwater wells, Dian-22 (D22) and Lijiang (LJ) well, in southeast Tibet Plateau in response to the 2015 Mw 7.8 Gorkha earthquake to illustrate hydrological implications. The coherences of water level and seismic wave before and after the far-field earthquake show systematic variations, which may confirm the coseismic dynamic shaking influence at high frequencies (f > 8 cpd). The tidal response of water levels in these wells shows abrupt coseismic changes of both phase shift and amplitude ratio after the earthquake, which may be interpreted as an occurrence in the vertical permeability of a switched semiconfined aquifer in the D22 well, or an enhancement unconfined aquifer in the LJ well. Using the continuous short-term transmissivity monitoring, we show that the possible coseismic response for about 10 days and instant healing after 10 days to the causal earthquake impact. Thus, the dynamic shaking during the Gorkha earthquake may have caused the short-term aquifer responses by reopening of preexisting vertical fractures and later healing at epicentral distances about 1500 km.

Projection of vegetation distribution to 1.5 °C and 2 °C of global warming on the Tibetan Plateau

Previous studies have identified vegetation shifts on the Tibetan Plateau in response to climate change. However, the speed and direction of these changes in alpine vegetation are not well understood. To quantify the responses of the distribution of alpine vegetation to global warming of 1.5 °C or 2 °C, BIOME4 was modified using the Penman–Monteith equation to estimate the reference evapotranspiration, and was run with projected climate data under the RCP4.5 and RCP8.5 scenarios. Gradients of temperature (1–5 °C) and precipitation (−30%–30%) were used to examine the sensitivity of changes in the vegetation pattern to climate. This study suggests that forests on the Tibetan Plateau will expand northwestward with climate warming. Among all forest types, the distribution area of broad-leaved forests will show the greatest increase, whereas mixed needle-broad-leaved forests will show the greatest percentage decrease (~45.5%) relative to the baseline period. Climate warming will result in alpine shrub expansion towards the interior of the Tibetan Plateau, with an average center shift of 309 km under the RCP4.5 scenario with a warming of 1.5 °C. A proportion of alpine meadow will be replaced by alpine shrub, causing it to shrink by ~6.8% under RCP4.5 with a warming of 1.5 °C and by ~15.5% under RCP8.5 with a warming of 2 °C. We conclude that all vegetation types on the Tibetan Plateau are susceptible to a warming climate. Increasing temperatures will move the vegetation boundaries northwestward and this trend will be enhanced by increases in precipitation. Understanding the response of vegetation patterns to warming will facilitate better strategies for carbon storage management. • Response of vegetation distribution under global warming on the Tibetan Plateau • A BIOME4 model was modified by using Penman-Monteith model • Alpine vegetation distribution may be altered under global warming of 1.5 and 2 °C • Temperature increase may move vegetation boundary northwestwardly • Lead to better strategies on vegetation conservation and carbon management

Photohydroionisation for disinfection of poultry litter

ABSTRACT 1. This study evaluated photohydroionisation efficiency on the disinfection of new shavings used as substrate for litter in the poultry industry, pre-inoculated with bacterial, fungal and viral agents. 2. Each replicate consisted of 250 g of new shavings sterilised by autoclaving, challenged with bacterial (Escherichia coli, Staphylococcus aureus, and Salmonella enterica, serovar Abony), fungal (Saccharomyces cerevisiae) and viral inoculum (Gumboro disease virus). The experiment consisted of six replicates at four times (0, 1, 5 or 10 min exposure) of photohydroionisation. The disinfection process was performed in a bench photohydroionisation device with four ultraviolet lamps. The agents inoculated in the shavings were analysed after the disinfection process. 3. The counts of enterobacteria and total bacteria showed a quadratic effect. In contrast, the counts of fungi and viruses showed a negative linear effect with an increase in the time of photohydroionisation. The enterobacteria showed a linear response plateau effect (LRP), with a minimum time point of 5.498 minutes at a minimum contamination of 0.666 CFU/g and a reduction of 82.27% of the pre-established inoculum. Total bacteria had an LRP effect with a minimum time point of 1.902 minutes at minimum contamination of 1.739 CFU/g and a reduction of 50.0% of the pre-established inoculum. An LRP effect was found for fungi, with a minimum time point of 7.931 minutes in minimum contamination of 3.380 CFU/g, and with a reduction of 11.0% of the pre-established inoculum. For viruses, there was an LRP effect with a minimum time point of 5.012 minutes in minimum contamination of 0.000 viral titre per 100 g of shavings, which was reduced by 100% of the pre-established inoculum. 4. Photohydroionisation in the disinfection of new shavings used as poultry litter has partial potential as a microbiological control tool, as a complete reduction occurred only for the viruses, whereas for bacteria and fungi only partial reductions of these microorganisms were observed.

POS1054 UPADACITINIB PHARMACOKINETICS AND EXPOSURE-RESPONSE RELATIONSHIPS FOR EFFICACY AND SAFETY IN PSORIATIC ARTHRITIS – ANALYSES OF THE PHASE 3 SELECT-PsA STUDIES

Background:Upadacitinib (UPA) is an oral, reversible, JAK inhibitor approved for the treatment of rheumatoid arthritis (RA). The efficacy and safety profile of UPA in psoriatic arthritis (PsA) has been established in the SELECT-PsA program which includes two global Phase 3 studies.Objectives:These analyses characterize UPA pharmacokinetics and exposure-response relationships for efficacy and safety endpoints using data from the SELECT-PsA studies.Methods:The SELECT-PsA program enrolled patients with prior inadequate response (IR) or intolerance to ≥1 non-bDMARD1 (N=1705) and prior IR or intolerance to ≥1 bDMARD2 (N=642). Data from both trials was integrated for patients receiving placebo (PBO), UPA 15mg once daily (QD) and UPA 30mg QD; adalimumab data was excluded from this analysis. UPA pharmacokinetics were characterized in PsA patients using Bayesian population pharmacokinetics analyses and utilizing prior information from analyses in healthy subjects and RA patients. Exposure-response analyses were conducted using logistic regression to characterize the relationships between upadacitinib average plasma concentration during a dosing interval (Cavg) and the percentage of patients achieving ACR20/50/70 at Weeks 12 and 24, static Investigator Global Assessment of psoriasis (sIGA) of 0 or 1 (clear or almost clear) and at least a 2-point improvement from baseline, and PASI75 at Weeks 16 and 24 or experiencing selected clinically relevant safety events through week 24.Results:Analyses were conducted using data from 1694 subjects (for pharmacokinetics) and 1916 subjects (for exposure-response analyses). UPA model-estimated plasma exposures in subjects with PsA who received 15mg and 30mg QD doses were comparable to previously estimated exposures in subjects with RA. Body weight and methotrexate use had no clinically relevant effects on UPA exposures. There was a statistically significant relationship between UPA Cavg and the percentage of subjects who achieved Week 12 ACR50/70, Week 16 sIGA 0/1, and Week 24 sIGA 0/1 (Figure 1). No statistically significant exposure-response relationship was observed for Week 12 ACR20, Week 16 PASI75, or Week 24 ACR20/50/70 or PASI75, indicating that the 15mg QD exposures are approximately at the plateau of response for these endpoints. No statistically significant relationships were observed between upadacitinib Cavg and the percentage of subjects experiencing pneumonia, herpes zoster, hemoglobin &lt; 8 g/dL, Grade ≥3 lymphopenia, Grade ≥3 neutropenia. There was a shallow but statistically significant exposure-response relationships with the occurrence of serious infections and decrease in hemoglobin from baseline (&gt;2 g/dL and &gt;2 g/dL in combination with hemoglobin &lt; lower limit for normal).Figure 1.Observed and Model Predicted Efficacy Responses at Week 12 (for ACR50/70) or at Weeks 16 and Week 24 (for sIGA 0/1) Versus Upadacitinib Plasma ExposuresConclusion:Exposure-response analyses demonstrated that plasma exposures associated with UPA 15 mg QD achieves robust efficacy in subjects with PsA with limited effects on the evaluated safety endpoints. UPA plasma exposures associated with UPA 15 and 30mg QD are predicted to provide similar ACR responses by week 24 while a small additional efficacy benefit with UPA 30mg is predicted for the achievement sIGA 0/1.

Impact of recreational transformation of soil physical properties on micromolluscs in an urban park

The paper assesses the effect of transformation of soil physical properties on the abundance of micromolluscs in the conditions of an urban park. The studies were carried out in Novooleksandrivskiy Park (Melitopol, Ukraine). An experimental polygon was represented by 7 transects with 18 sampling points in each. The interval between the points in the transect, as well as the interval between transects, was 3 meters. The total area of the polygon was 1,134 m2. The tree species growing within the polygon were Quercus robur, Sophora japonica, and Acer campestre. Shrubs were represented by Ulmus laevis, Tilia cordata, Celtis occidentalis, and Morus nigra. The locations of the trees and shrubs were mapped. The crowns of tree and shrub plants formed a dense canopy and a shady light regime. The grass cover was practically absent. The soil mechanical resistance, soil aggregate-size distribution, electrical conductivity of soil, soil moisture and bulk density were measured. We recorded 618 individuals of Vallonia pulchella, 120 individuals of Cochlicopa lubrica, and 58 individuals of Acanthinula aculeata within the surveyed polygon. We extracted three principal components, which could explain 60.9% of the variation in the feature space of the soil properties. The principal component 1 explained 42.0% of the variation of the feature space and depended on the soil penetration resistance throughout the whole profile, aggregate composition, density, electric conductivity and moisture content of soil. This component reflected a tendency for soil penetration resistance and soil density to increase near recreational trails. The principal component 1 was used to indicate the gradient of recreational transformation of the soil. The principal component 2 was able to explain 10.6% of the variation in the feature space. It negatively correlated with the distance from the recreational trail, soil penetration resistance at the depth of 35 cm or more, soil electrical conductivity, and the proportion of aggregates greater than 3 mm in size. This component positively correlated with soil penetration resistance at 0–5 cm depth and the proportion of aggregates less than 0.5 mm in size. This component can be interpreted as a "halo" from the recreational trail, or a gradient of indirect soil transformations adjacent to the zone of intense recreational load. The principal component 3 was able to explain 8.3% of the variation in the feature space. It positively correlated with soil penetration resistance at the depth of 20–40 cm, the proportion of 0.5–7.0 mm aggregates, and soil moisture. It negatively correlated with the proportion of aggregates larger than 7 mm and smaller than 0.25 mm. This component indicated a variation in soil properties that was induced by causes independent of recreational exposure. The extracted gradients of soil properties significantly influenced the abundance of micromollusc populations. The abundance of all species decreased after increase in recreational load. Micromollusc species responded to direct recreational exposure as plateau (C. lubrica) and asymmetric unimodal responses (V. pulchella and A. aculeata).

Pollen-based mapping of Holocene vegetation on the Qinghai-Tibetan Plateau in response to climate change

Improved studies of past vegetation change are required to better understand the variation of alpine ecosystems on the Qinghai-Tibetan Plateau (QTP) in response to future climate change. Spatial and temporal variations of past vegetation can be traced by fossil pollen data mapping. In this paper, we synthesized 57 continuous pollen records on the QTP covering the past 15 kyr to depict large-scale vegetation change and its response to climate variations. In order to minimize potential chronological biases, age-depth models were revised using a state-of-the-art and consistent method for all the records. The spatial and temporal variation of major pollen taxa were examined based on interpolated pollen maps at 1000-year intervals. The arboreal pollen (AP, mainly of Pinus, Betula and Abies/Picea) content expressed significant climate signals over a broad spatial and temporal gradient. During the late glacial period, high proportions of AP widely occurred in regions that are presently unforested owing to the sparse local vegetation coverage. For the Holocene period, AP showed relatively high contributions in records from the southeastern margin of the QTP, with a decreasing gradient in abundance towards the northwest. The transportation of AP to unforested regions corresponds closely to the intensity of monsoon wind, which can be used to track the Holocene evolution of the summer monsoon. The dominant shrub and herbaceous taxa (including Artemisia, Chenopodiaceae, Cyperaceae, Poaceae and Ephedra) generally represent developments of local vegetation responding to climate variations. In addition, the persistent increase in Poaceae pollen during the mid to late Holocene correlates possibly to regional human activities. The inferred spatial and temporal patterns of major pollen types on the QTP provide significant knowledge about long-term vegetation change and its potential response to climate variations.

Neuromodulation Effect of Very Low Intensity Transcranial Ultrasound Stimulation on Multiple Nuclei in Rat Brain.

ObjectiveLow-intensity transcranial ultrasound stimulation (TUS) is a non-invasive neuromodulation technique with high spatial resolution and feasible penetration depth. To date, the mechanisms of TUS modulated neural oscillations are not fully understood. This study designed a very low acoustic intensity (AI) TUS system that produces considerably reduced AI Ultrasound pulses (ISPTA < 0.5 W/cm2) when compared to previous methods used to measure regional neural oscillation patterns under different TUS parameters.MethodsWe recorded the local field potential (LFP) of five brain nuclei under TUS with three groups of simulating parameters. Spectrum estimation, time-frequency analysis (TFA), and relative power analysis methods have been applied to investigate neural oscillation patterns under different stimulation parameters.ResultsUnder PRF, 500 Hz and 1 kHz TUS, high-amplitude LFP activity with the auto-rhythmic pattern appeared in selected nuclei when ISPTA exceeded 12 mW/cm2. With TFA, high-frequency energy (slow gamma and high gamma) was significantly increased during the auto-rhythmic patterns. We observed an initial plateau in nuclei response when ISPTA reached 16.4 mW/cm2 for RPF 500 Hz and 20.8 mW/cm2 for RPF 1 kHz. The number of responding nuclei started decreasing while ISPTA continued increasing. Under 1.5 kHz TUS, no auto-rhythmic patterns have been observed, but slow frequency power was increased during TUS. TUS inhibited most of the frequency band and generated obvious slow waves (theta and delta band) when stimulated at RPF = 1.5 kHz, ISPTA = 8.8 mW/cm2.ConclusionThese results demonstrate that very low intensity Transcranial Ultrasound Stimulation (VLTUS) exerts significant neuromodulator effects under specific parameters in rat models and may be a valid tool to study neuronal physiology.

Untuned broadband spiral micro-coils achieve sensitive multi-nuclear NMR TX/RX from microfluidic samples

The low frequency plateau in the frequency response of an untuned micro-resonator permits broadband radio-frequency reception, albeit at the expense of optimal signal-to-noise ratio for a particular nucleus. In this contribution we determine useful figures of merit for broadband micro-coils, and thereby explore the parametric design space towards acceptable simultaneous excitation and reception of a microfluidic sample over a wide frequency band ranging from 13C to 1H, i.e., 125–500 MHz in an 11.74 T magnet. The detector achieves 37% of the performance of a comparably sized, tuned and matched resonator, and a linewidth of 17 ppb using standard magnet shims. The use of broadband detectors circumvents numerous difficulties introduced by multi-resonant RF detector circuits, including sample loading effects on matching, channel isolation, and field distortion.

Rheological response of soft flake-shaped carbonyl iron water-based MR fluid containing iron nanopowder with hydrophilic carbon shell

In this work, the rheological response and sedimentation stability of micron-sized flake-shaped carbonyl iron (CI) water-based magnetorheological (MR) fluid were investigated using iron nanopowder with hydrophilic carbon shell as an additive. The rheological behaviors of MR fluid containing 1 wt% iron nanopowder were measured with and without a magnetic field under shear rate, shear strain, and shear stress sweep mode using a parallel plate rotational rheometer. The magnetic field strength was varied from 0 to 131 kA/m, and in the presence of magnetic field strength, micron flake-shaped CI and iron nanopowder particles lead to form a robust columnar structure. It was observed that using 1 wt% of iron nanopowder with hydrophilic carbon shell, the rheological responses and sedimentation stability of MR suspension were enhanced. We fitted the shear stress as a function of shear rate curves using the Bingham-plastic flow model, which shows a good agreement with the experimental results. We find that yield stress obtained in shear rate sweep mode was larger than that in the shear strain and shear stress sweep mode because, in shear strain and shear stress mode, the responding strain (or stress) may be unable to follow the stress (or strain) applied and a smaller value of strain (or stress) was observed. The amplitude sweep reveals a transition from viscoelastic-to-viscous behavior at the critical strainγcrt = 0.1%. The storage modulus (G') of the MR fluid showed a stable plateau region over the small strain area γ ≤ γcrt and G'independent of strain amplitude. The frequency sweep demonstrated that storage moduli (G') exhibit elastic response and stable plateau region over the entire frequency range, suggesting the distinguished solid-like behavior of the MR fluid.

Mapping Surficial Soil Particle Size Fractions in Alpine Permafrost Regions of the Qinghai–Tibet Plateau

Spatial information of particle size fractions (PSFs) is primary for understanding the thermal state of permafrost in the Qinghai-Tibet Plateau (QTP) in response to climate change. However, the limitation of field observations and the tremendous spatial heterogeneity hamper the digital mapping of PSF. This study integrated log-ratio transformation approaches, variable searching methods, and machine learning techniques to map the surficial soil PSF distribution of two typical permafrost regions. Results showed that the Boruta technique identified different covariates but retained those covariates of vegetation and land surface temperature in both regions. Variable selection techniques effectively decreased the data redundancy and improved model performance. In addition, the spatial distribution of soil PSFs generated by four log-ratio models presented similar patterns. Isometric log-ratio random forest (ILR-RF) outperformed the other models in both regions (i.e., R2 ranged between 0.36 to 0.56, RMSE ranged between 0.02 and 0.10). Compared with three legacy datasets, our prediction better captured the spatial pattern of PSFs with higher accuracy. Although this study largely improved the accuracy of spatial distribution of soil PSFs, further endeavors should also be made to improve model accuracy and interpretability for a better understanding of the interaction and processes between environmental predictors and soil PSFs at permafrost regions.

Magnetostratigraphic study of a Late Cretaceous–Paleogene succession in the eastern Xining basin, NE Tibet: Constraint on the timing of major tectonic events in response to the India-Eurasia collision

Abstract Cretaceous-Cenozoic basins developed in the NE Tibetan Plateau contain key archives to unravel the growth history of the plateau in response to the India-Eurasia collision. Here we present magnetostratigraphic results of a Late Cretaceous to Paleogene succession of the Zhongba section outcropping at the southern margin of the eastern Xining basin. This succession consists of three lithological units punctuated by two stratigraphic unconformities, which best recorded the deformation history of this foreland basin. Detailed magnetostratigraphic investigation show that the lower terrestrial sedimentary rock unit, the Minhe Group, was deposited in latest Cretaceous in the time span of ca. 74.5–69.2 Ma; the middle unit was deposited in Paleogene in the time span of ca. 49.3–22 Ma; and the upper conglomeratic unit, not dated, possibly was deposited in early Miocene. Accordingly, the Cretaceous–Paleogene unconformity, widely observed in the foreland basins of NE Tibet, represents a sedimentary hiatus duration of ∼19.9 m.y., from ca. 69.2 Ma to ca. 49.3 Ma, which possibly recorded the far-field response to the tectonic transition from Neo-Tethys oceanic plate subduction to the India-Eurasia collision in southern Tibet. Changes in provenance, sedimentary accumulation rate, and mean susceptibility value at ca. 33–30 Ma, and the total prolate anisotropy of magnetic susceptibility (AMS) ellipsoids and provenance shifting since ca. 23–19 Ma, point to the pulsed growth of West Qinling, and rapid uplift of Laji Shan, respectively, indicating an enhanced effect of the India-Eurasia collision in Oligocene and early Miocene. AMS results show a clockwise rotation of the shortening direction from NEN-SWS in latest Cretaceous to NE-SW in Paleogene.

Lieb-Schultz-Mattis-type theorems and other nonperturbative results for strongly correlated systems with conserved dipole moments

Non-perturbative constraints on many body physics--such as the famous Lieb-Schultz-Mattis theorem--are valuable tools for studying strongly correlated systems. To this end, we present a number of non-perturbative results that constrain the low-energy physics of systems having conserved dipole moments. We find that for these systems, a unique translationally invariant gapped ground state is only possible if the polarization of the system is integer. Furthermore, if a lattice system also has $U(1)$ subsystem charge conservation symmetry, a unique gapped ground state is only possible if the particle filling along these subsystems is integer. We also apply these methods to spin systems, and determine criteria for the existence of a new type of magnetic response plateau in the presence of a non-uniform magnetic field. Finally, we formulate a version of Luttinger's theorem for 1D systems consisting of dipoles.

Tamanho de amostra para avaliação do grau de multicolinearidade em caracteres produtivos de centeio

The objectives of this work were to determine the sample size (number of plants) necessary to estimate the indicators of the of multicollinearity degree - condition number (CN), determinant of the correlation matrix (DET), and variance inflation factor (VIF) - in productive traits of rye and to verify the variability of the sample size between the indicators. Five and three uniformity trials were conducted with the cultivars BRS Progresso and Temprano, respectively, and seven productive traits were evaluated in 780 plants. Twenty-one cases were obtained from seven traits, combined five to five. In each case, 197 sample sizes were planned (20, 25, 30, ..., 1,000 plants) and in each size 2,000 resampling were performed, with replacement. For each resample the CN, DET and FIV were determined and the average among 2,000 estimates of each indicator of the multicollinearity degree was calculated. Then, for each case and indicator, the sample size was determined through three models: models of maximum modified curvature, segmented linear with plateau response, and segmented quadratic with plateau response. There was superiority the quadratic model segmented with plateau in adjusting the degree of multicollinearity according to the sample size for all indicators. There is a need greater sample size to detect multicollinearity when diagnosed by DET and for sizes larger than 101, 258 and 102 plants when diagnosing for the number of conditions, determinant and inflation factor performed, respectively.

Número suficiente de repetições para análise de trilha em milho

The number of replications is assumed to interfere in the estimates of the path analysis coefficients. Thus, the objective of this work was to determine the sufficient number of replications for the path analysis of traits in maize cultivars. An experiment was conducted with 15 maize cultivars in a complete randomized block design with nine replications, and seven variables were measured. Then, 511 data files (matrices) formed by all combinations of the nine replications were organized, in groups of 1, 2, 3, 4, 5, 6, 7, 8 and 9 replications. In each matrix, containing the averages of 15 cultivars for the seven variables, Pearson's linear correlation coefficients were estimated, the multicollinearity diagnostics and path analysis were performed and dispersion diagrams were constructed. The sufficient number of replications for the path analysis was determined from the parameter estimates of the quadratic response plateau model. With the replications number increases, the accuracy of the path analysis coefficient estimates improves, but the gains in accuracy gradually decrease. Six replications are sufficient to perform the path analysis of agronomic traits of maize cultivars and can be used as a reference for designing future experiments.

Rice bran as a substitute for soy protein and erythorbate in chicken nuggets

The aim of this work was to compare three methods of estimating the optimal plot size for evaluating fresh matter in the IPR91-Baili and IPR92-Altar cultivars of buckwheat (Fagopyrum esculentum Moench). Sixteen uniformity trials (blank experiments) were conducted, eight with the IPR91-Baili cultivar and eight with the IPR92-Altar cultivar. The trials were carried out at eight different sowing times. The fresh matter was evaluated in 576 basic experimental units (BEU), each 1 m × 1 m in size (36 BEU per trial). The optimal plot size was determined using the method of modified maximum curvature, the linear response plateau model and the quadratic response plateau model. The optimal plot size differs between methods, and decreases in the following order: quadratic response plateau model, linear response plateau model and modified maximum curvature. The optimal plot size for evaluating fresh matter in the IPR91-Baili and IPR92-Altar cultivars of buckwheat is 7.60 m2. This size can be used as a reference for future experiments with buckwheat.

Preservation of Organ Function in Locally Advanced Non-Metastatic Gastrointestinal Stromal Tumors (GIST) of the Stomach by Neoadjuvant Imatinib Therapy.

Simple SummaryThis study reports a single-center analysis of 55 patients with primary, locally advanced gastric GIST treated with imatinib mesylate (IM) preoperatively for a median of 10 months. The therapy yielded shrinkage of median tumor size from 113 mm to 62 mm. This facilitated 50 patients to undergo significantly less-extensive surgical procedures and resulted in a stomach preservation rate of 96%. The rate of R0 resections was 94% and was followed by a mean recurrence-free-survival time of 132 months with the median not reached. The approach was successful even for patients starting IM during an episode of upper gastrointestinal bleeding. Neoadjuvant IM therapy for locally advanced, non-metastatic gastrointestinal stromal tumors (GIST) of the stomach may play an important role in preserving organ function which might be important for IM plasma levels in an adjuvant or metastatic setting.Background: Neoadjuvant imatinib mesylate (IM) for advanced, non-metastatic gastrointestinal stromal tumors (GIST) of stomach is recommended to downsize the tumor prompting less-extensive operations and preservation of organ function. Methods: We analyzed the clinical-histopathological profile and oncological outcome of 55 patients (median age 58.2 years; range, 30–86 years) with biopsy-proven, cM0, gastric GIST who underwent IM therapy followed by surgery with a median follow-up of 82 months. Results: Initial median tumor size was 113 mm (range, 65–330 mm) and 10 patients started with acute upper GI bleeding. After a median 10 months (range, 2–21 months) of treatment, tumor size had shrunk to 62 mm (range, 22–200 mm). According to Response Evaluation Criteria In Solid Tumors version 1.0 and version 1.1 (RECIST 1.1), 39 (75%) patients had partial response and 14 patients had stable disease, with no progressive disease. At plateau response, 50 patients underwent surgery with an R0 resection rate of 94% and pathological complete response in 24%. In 12 cases (24%), downstaging allowed laparoscopic resection. The mean recurrence-free survival (RFS) was 123 months (95%CI; 99–147) and the estimated 5-year RFS was 84%. Conclusions: Neoadjuvant IM allowed stomach preservation in 96% of our patients with excellent long-term RFS, even when starting treatment during an episode of upper GI bleeding. Preservation of the stomach provides the physiological basis for the use of oral IM in the adjuvant or metastatic setting.

Inseminating dose for the artificial fertilization of Brycon amazonicus (Teleostei: Characidae).

Knowledge of the sperm-oocyte ratio in fish fertilization serves as the basis for studies on artificial reproduction and gamete manipulation. The aim of this study was to determine the minimum insemination dose for Brycon amazonicus oocyte fertilization. Female and male gametes were used and tested with the following doses of spermatozoa oocyte-1 ml-1: 10,000, 20,000, 40,000, 60,000 and 80,000 (in triplicate). Fertilization rates were calculated and estimated from the regression equation by applying the segmented regression model 'Linear Response Plateau' to determine the appropriate proportion of gametes. Based on the equation Ŷ = 14.3415 + 0.0007836X, the fertilization rate increased up to 63.34% as it reached a plateau with a proportion of 62,524 spermatozoa oocyte-1 ml-1, which is the minimum insemination dose recommended for artificial insemination of the species.

Study of the Characteristics of the Pulmonary Vein and Superior Vena Cava of Rabbits

Background: This study aims to (1) investigate the characteristics of the action potential and triggering activity of cardiomyocytes in the pulmonary vein (PV) and superior vena cava (SVC) of rabbits and (2) study the features of cation currents in cardiomyocytes in rabbit PV and SVC-inward rectifier potassium current (IK1), transient outward potassium current (Ito), and non-selective cation currents (INSCC). Methods: The standard glass microelectrode and whole-cell patch-clamp techniques were used to record the action potential and various currents in the above cells. Results: (1) Cardiomyocytes in either PV or SVC had longer action potential durations than in the adjacent atrium, and spontaneous early after depolarization (EAD) could occur in both PV and SVC under normal physiological conditions. (2) The action potential in PV cardiomyocytes had a relative refractory period but did not have an absolute refractory period, and this characteristic enabled a premature beat that triggered a second plateau response, which led to EAD. (3) INSCC was found for the first time in the PV, SVC, and atria. (4) The current intensity of IK1, Ito, and INSCC was significantly lower in the PV and SVC than in the left and right atria, and the difference in the current intensity in INSCC could influence the action potential. Conclusions: PV and SVC can both initiate and maintain AF, but PV is the primary ectopic foci in initiating AF. The present study found that the second plateau response was easily induced in cardiomyocytes in PA shortly after depolarization. This was a specific characteristic of the action potential of PV. In addition, we preliminarily analyzed the differences in the main outward currents and noted a voltage-dependent INSCC in both PV and SVC rabbits’ cardiomyocytes. Furthermore, the current intensities of IK1, Ito, and INSCC were significantly lower in the PV and SVC than in the left and right atria, and the difference in the current intensity of INSCC influenced the action potential. The different permeability of INSCC for cations at different phases may play a role in inducing EAD.