Positive Quadratic Relationship Research Articles

Direct observation of NMR transverse relaxation in nanopatterned clusters of iron oxide particles.

We aim to verify predictions showing T2 relaxation rate of nanoparticle clusters and its dependence on spacing, size, geometry, and pulse sequence. We performed a laboratory validation study using nanopatterned arrays of iron oxide nanoparticles to precisely control cluster geometry and image diverse samples using a 4.7T MRI scanner with a T2 -weighted fast spin-echo multislice sequence. We applied denoising and normalization to regions of interest and estimated relative R2 for each relevant nanoparticle array or nanocluster array. We determined significance using an unpaired two-tailed t-test or one-way analysis of variance and performed curve fitting. We measured a density-dependent T2 effect (p = 8.9976 × 10-20 , one-way analysis of variance) and insignificant effect of cluster anisotropy (p = 0.5924, unpaired t-test) on T2 relaxation. We found negative quadratic relationships (-0.0045[log τD ]2 -0.0655[log τD ]-2.7800) for single nanoparticles of varying sizes and for clusters (-0.0045[log τD ]2 -0.0827[log τD ]-2.3249) for diffusional correlation time τD = rp 2 /D. Clusters show positive quadratic relationships for large (3.8615 × 10-6 [dpp /rp ]2 -9.3853 × 10-5 [dpp /rp ]-2.0393) and exponential relationships for small (-2.0050[dpp /rp ]0.0010 ) clusters. Calculated R2 peak values also align well with in silico predictions (7.85 × 10-4 ms compared with 1.47 × 10-4 , 4.23 × 10-4 , and 5.02 × 10-4 ms for single iron oxide nanoparticles, 7.88 × 10-4 ms compared with 5.24 × 10-4 ms for nanoparticle clusters). Our verification affirms longstanding in silico predictions and demonstrates aggregation-dependent behavior in agreement with previous Monte Carlo simulation studies.

Is there a g in gunslinger? Cognitive predictors of firearms proficiency

This study addressed a gap in the research literature by evaluating the validity of general mental ability (g) and personality test scores for prediction of firearms proficiency via shooting range performance, an entirely objective task-based criterion. It was hypothesized that mental ability test scores would be positively related to firearms proficiency based on past research in related areas (e.g., g predicts skill acquisition and training performance) and conceptual similarities between firearms proficiency and cognitive tasks. Using 4 datasets with a combined sample size of 22,525 individuals, this hypothesis was confirmed: g had operational validities ranging from .162 to .188 and logical reasoning had operational validities ranging from .179 to .268 after correcting for range restriction and criterion unreliability. Mental ability test scores predicted an entirely psychomotor criterion task: use of firearms to hit targets at a pre-determined level of accuracy. Most of the validity appears to be attributable to g, but a post hoc analysis indicated that writing ability acted as a suppressor (i.e., the validity of g increased when writing ability was included in a regression model). Conscientiousness was hypothesized to have a positive relationship with firearms performance and emotional stability was hypothesized to have positive linear and quadratic relationships. In contrast, it was observed that conscientiousness had a negative operational validity (−.079) and emotional stability lacked validity relative to the firearms proficiency criterion. The implications for individual differences research and practice are discussed.

Reasoning biases and delusional ideation in the general population: A longitudinal study.

Reasoning biases have been suggested as risk factors for delusional ideation in both patients and non-clinical individuals. Still, it is unclear how these biases are longitudinally related to delusions in the general population. We hence aimed to investigate longitudinal associations between reasoning biases and delusional ideation in the general population. We conducted an online cohort study with 1184 adults from the German and Swiss general population. Participants completed measures on reasoning biases (jumping-to-conclusion bias [JTC], liberal acceptance bias [LA], bias against disconfirmatory evidence [BADE], possibility of being mistaken [PM]) and delusional ideation at baseline, and delusional ideation 7 to 8months later. A greater JTC bias was associated with a greater increase in delusional ideation over the following months. This association was better described by a positive quadratic relationship. Neither BADE, LA nor PM were associated with subsequent changes in delusional ideation. This study suggests that jumping-to-conclusions predicts delusional ideation in the general population but that this association may follow a quadratic trajectory. While no other associations turned significant, future studies with shorter temporal distances may shed further light on the role of reasoning biases as risk factors for delusional ideation in non-clinical samples.

Feeding behavior parameters and temporal patterns in mid-lactation Holstein cows across a range of residual feed intake values.

Residual feed intake (RFI) is a measurement of the difference between actual and predicted feed intake when adjusted for energy sinks; more efficient cows eat less than predicted (low RFI) and inefficient cows eat more than predicted (high RFI). Data evaluating the relationship between RFI and feeding behaviors (FB) are limited in dairy cattle; therefore, the objective of this study was to determine daily and temporal FB in mid-lactation Holstein cows across a range of RFI values. Mid-lactation Holstein cows (n = 592 multiparous; 304 primiparous) were enrolled in 17 cohorts at 97 ± 26 d in milk (± standard deviation), and all cows within a cohort were fed a common diet using automated feeding bins. Cow RFI was calculated as the difference between predicted and observed dry matter intake (DMI) after accounting for parity, days in milk, milk energy, metabolic body weight and change, and experiment. The associations between RFI and FB at the level of meals and daily totals were evaluated using mixed models with the fixed effect of RFI and the random effects of cow and cohort. Daily temporal FB analyses were conducted using 2-h blocks and analyzed using mixed models with the fixed effects of RFI, time, RFI × time, and cohort, and the random effect of cow (cohort). There was a positive linear association between RFI and DMI in multiparous cows and a positive quadratic relationship in primiparous cows, where the rate of increase in DMI was less at higher RFI. Eating rate, DMI per meal, and size of the largest daily meal were positively associated with RFI. Daily temporal analysis of FB revealed an interaction between RFI and time for eating rate in multiparous and primiparous cows. The eating rate increased with greater RFI at 11 of 12 time points throughout the day, and eating rate differed across RFI between multiple time points. There tended to be an interaction between RFI and time for eating time and bin visits in multiparous cows but not primiparous cows. Overall, there was a time effect for all FB variables, where DMI, eating time and rate, and bin visits were greatest after the initial daily feeding at 1200 h, increased slightly after each milking, and reached a nadir at 0600 h (6 h before feeding). Considering the relationship between RFI and eating rate, additional efforts to determine cost-effective methods of quantifying eating rate in group-housed dairy cows is warranted. Further investigation is also warranted to determine if management strategies to alter FB, especially eating rate, can be effective in increasing feed efficiency in lactating dairy cattle.

Metric error monitoring for a cleaner record of timing.

A recent line of research has shown that humans can keep track of the direction and magnitude of their timing errors without relying on feedback. But these studies tested temporal error monitoring explicitly by interrogating participants regarding their errors, which might have inadvertently primed the prospective coupling between the first-order timing and second-order metacognitive judgments. The current study utilized an indirect way of testing temporal error awareness while providing a strong objective incentive for maximizing the accuracy of first-order timing performance. In two experiments, participants were asked to maximize the average proximity of their time reproduction to the target by accepting or rejecting their time reproduction depending on the subjective judgment of their proximity to the target time interval. We found that participants more frequently opted out of a trial with a larger distance between their reproductions and the target time interval in both directions, forming a positive quadratic relationship with reproduced time. Resultantly, timing precision was lower in trials that participants opted out of. Our results provide new evidence in support of the temporal error-monitoring performance of human participants. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Effect of interface geometric parameters on the mechanical properties and damage evolution of layered cemented gangue backfill: Experiments and models

• Mechanical properties of LCGB as a function of interface geometry parameters. • Effects of interface geometric parameters on damage evolution of LCGB. • Failure mode of LCGB is affected by interface geometric parameters. • Dynamic crack evolution law of LCGB during loading. Subsequent backfilling of widespread goaf generally necessitates multiple fillings to enrich the goaf, resulting in the layered structure of cemented gangue backfill. Therefore, it is of great significance to study the mechanical properties of layered cemented gangue backfill (LCGB) with different interface geometric parameters to ensure the stability of underground engineering. In this paper, the effects of interface roughness and interface angle on the mechanical properties and damage evolution of LCGB were comprehensively explored using uniaxial compression test, acoustic emission (AE) and digital image correlation (DIC). A numerical model of LCGB was built using simulation software (PFC2D) to demonstrate the dynamic crack evolution of LCGB during loading. The results demonstrate that LCGB's compressive strength and elastic modulus have positive linear and quadratic relationships with interface undulating angle and interface angle respectively, and that the rupture angle, which represents the worst mechanical properties of LCGB, is between 45° and 60°. Increasing the interface undulating angle can enhance the strain hardening characteristics of LCGB during the post-peak deformation stage and release more active AE signals. As the interface angle approaches the rupture angle, the peak stress of LCGB continues to deteriorate, and its AE signal appears more concentrated in the post-peak deformation stage. The surface principal strain of LCGB rises as the interface undulating angle increases, while it reduces first and then increases with the interface angle increases. The simulation process reveals that shear cracks mainly extend along the interface, whereas tension cracks propagation and coalescence the adjacent interface along the axial stress loading direction, and they converge to generate macroscopic defects that cause LCGB unstable failure.

Influence of Ceramsite with Assembly Unit of Sludge and Excavated Soil on the Properties of Cement Concrete.

The application of sludge in the manufacture of ceramic material provides an outlet for waste disposal. In this study, we aimed to produce a new lightweight aggregate applications in concrete. The influence of burning temperature on the ignition loss rate, cylinder compressive strength, and the water absorption rate of ceramsite mixed with sludge and excavated soil was investigated. The slump flow, apparent density, and mechanical strength (flexural and compressive strengths) of cement concrete with ceramsite were determined. Moreover, the chloride ion permeability coefficient and the thermal conductivity were tested. Finally, scanning electron microscopy, X-ray diffraction, and thermal analysis were applied to analyze the mechanisms of the properties of ceramsite. Results show that the ignition loss rate and the burning temperature are in a quadratic relationship. The cylinder compressive strength shows a positive quadratic relationship with the burning temperature. However, the water absorption rate negatively correlates with the burning temperature. The addition of sludge can increase the ignition loss rate and cylinder compressive strength of ceramsite. Meanwhile, the effect of sludge on the water absorption rate is the opposite. Ceramsite decreases the slump flow and the apparent density of cement concrete. Cement concrete with 10% ceramsite shows the highest mechanical strength and the lowest chloride ion migration coefficient. Correction of the chloride ion migration coefficient and the content of ceramsite was performed as an exponential equation. Ceramsite exerts a negative effect on the thermal conductivity of cement concrete. Concrete with sludge ceramsite shows higher slump flow, apparent density, mechanical strength, and resistance to chloride ion penetration and thermal conductivity than concrete sludge with clay ceramsite. The mullite content of sludge ceramsite is higher than that of clay ceramsite. Additionally, sludge ceramsite exhibits a denser structure than that of clay ceramsite.

255 Impact of Water Flow Rate on Finishing Pig Performance Under Commercial Conditions

Abstract A survey of South Dakota pork producers in 2019 reported that 68% had water flow rates above the recommended rate of 500-1,000 mL/min. The objective of this study was to determine the impact of water flow rate on finishing pig performance during from June to September in a commercial barn. A total of 1,227 mixed sex pigs (61 ± 4.38 kg) at 8-weeks post-wean were utilized in an 84-d trial with 26 pigs/pen and 2 cup waterers/pen. Pens were assigned to 1 of 3 water flow rates (high, medium, low) based on the 3-hole diameter of the water nipples (2.0, 1.0, 0.80 mm; n = 16 pens/setting). Individual pen water flow rate, water disappearance, BW, and feed disappearance were recorded every 2 weeks. Carcass data was collected at the conclusion of the trial. Water flow rates averaged 1,565±96, 1,115±265, and 605±203 mL/min for high, medium, and low flow rates, respectively. Ambient temperature ranged from 4 to 37 °C. There was no difference in growth performance based on means separation test. Due to variability of water flow rate within a setting, data was further analyzed using regression with flow rate as the independent variable. There was a positive quadratic relationship (P < 0.05) for daily water disappearance (adjR2 =0.87) and daily gain (adjR2 =0.11) with water flow rate and a tendency for positive linear relationship between final BW (P = 0.07, adj. R2 = 0.06) and flow rate. Feed conversion had a negative cubic relationship with water flow rate (P < 0.05, adj. R2 = 0.20) and no relationship between hot carcass weight or average daily feed intake and water flow rate. The low R2 values associated with pig performance and high association with water disappearance suggest that excess water flow rate has a low impact on finishing pig performance but contributes to water wastage and its associated costs.

Interaction of vitrinites in similar middle-rank coals during coking process

Interaction of vitrinites in coals during coking process has effect on the properties of the coke. The evaluation of the vitrinites interaction is of great significance of coal blending and coke quality prediction. Vitrinites separated from the similar middle-rank coals in Tangshan (TS) and Ewirgol (EW) are mixed with ratio of 0:1, 1:3, 1:1, 3:1, 1:0 to prepare cokes. The characteristics of coke-CO2 gasification were studied to evaluate the interaction of vitrinites during coking process. The results show that the maximum reaction rate (rmax) and the comprehensive gasification index (Gc) of cokes have negative quadratic linear relationships with the content of TS vitrinite, and the difference between the experimental and theoretical gasification reactivity of cokes indicates the interaction of EW and TS vitrinites in the coking process. An interaction index (δ) based on the gasification reactivity of cokes is proposed to characterize the degree of interaction between the two kinds of vitrinites in coking process, and the interaction index based on Gc is 6.9%. Also, XRD and Raman spectroscopy analysis results show that the microcrystalline structure parameters (n and fa) have a negative linear relationship with Gc, and the Raman parameter AD1+D2+D3+D4/AG has a positive quadratic linear relationship with Gc, the Raman parameter AG/AAll has a negative quadratic linear relationship with Gc. TS vitrinite in coal blending can enhance the graphite characteristics in the coke and increase the order degree of carbon structure in the coke, which improve the resistance of CO2 erosion for the cokes.

Dynamic functional connectivity profile of the salience network across the life span

The insular cortex and anterior cingulate cortex together comprise the salience or midcingulo‐insular network, involved in detecting salient events and initiating control signals to mediate brain network dynamics. The extent to which functional coupling between the salience network and the rest of the brain undergoes changes due to development and aging is at present largely unexplored. Here, we examine dynamic functional connectivity (dFC) of the salience network in a large life span sample (n = 601; 6–85 years old). A sliding‐window analysis and k‐means clustering revealed five states of dFC formed with the salience network, characterized by either widespread asynchrony or different patterns of synchrony between the salience network and other brain regions. We determined the frequency, dwell time, total transitions, and specific state‐to‐state transitions for each state and subject, regressing the metrics with subjects' age to identify life span trends. A dynamic state characterized by low connectivity between the salience network and the rest of the brain had a strong positive quadratic relationship between age and both frequency and dwell time. Additional frequency, dwell time, total transitions, and state‐to‐state transition trends were observed with other salience network states. Our results highlight the metastable dynamics of the salience network and its role in the maturation of brain regions critical for cognition.

288 Plasma Concentrations of Cortisol During the Periparturient Period in Gilts

Abstract An increase in plasma concentrations of cortisol is one signal that begins parturition and uterine contractions in pregnant sows; however, it is not known whether a critical level of cortisol is necessary or the role that it may play in the duration of parturition. The objective of the study was to characterize plasma concentrations of during the periparturient period and assess its relationship with initiation of parturition, litter size, and farrowing duration. Blood was collected via indwelling catheters from 5 primiparous gilts twice daily (0700 and 1900 h) from d113 of gestation until the birth of the first piglet, after which blood was collected every 15 minutes until farrowing was considered complete. Time of birth of each piglet was recorded. Farrowing duration was defined as the time between birth of the first and last piglets. Plasma concentrations of cortisol were determined by radioimmunoassay. Litter size was 12, 12, 18, 17, and 14 piglets and farrowing duration was 72 minutes, 4.1, 6.7, 5.8, and 4 hours, respectively. Quadratic and linear regressions were performed using the RStats package in RStudio (version 1.2.5025). Serum concentrations of cortisol were 3.37 ± 1.55 and 5.73 ± 2.18 ng/mL prior to parturition and at the birth of the first piglet, respectively. There was a positive quadratic relationship (P ≤ 0.07) between time of birth of each piglet and plasma cortisol levels; peak cortisol was 14.45 ± 3.20 ng/mL. There was a positive correlation between initial cortisol level and average piglet birth weight (P = 0.0124) but no relationship with total litter weight (P > 0.05). Determination of the periparturient changes in cortisol may be useful in designing farrowing induction protocols.

Effect of irrigation level on plant growth, physiology and fruit yield and quality in bell pepper (Capsicum annuum L.)

The objective of this study was to evaluate the influence of drip irrigation level on plant growth, physiology, and fruit yield and quality in bell pepper. Bell pepper (‘Aristotle’) was grown on plastic film mulch in a sandy-loam soil in the spring of 2017 and 2018 in Tifton, GA. Four treatments with varying irrigation levels were applied: 33 %, 67 %, 100 % and 133 % - the rate of crop evapotranspiration (ETc). Irrigation level differentially affected plant growth, physiology and fruit yield and quality. Leaf water potential increased as the irrigation level increased. Leaf net photosynthesis (Pn), internal CO2 (Ci), electron transport rate (ETR), photosystem II efficiency (PSII), stomatal conductance (gs), and transpiration displayed a positive quadratic relationship with irrigation level. Plant height, stem diameter, leaf number per plant, shoot dry weight and stem fresh and dry weight also showed a positive quadratic relationship with irrigation level. Irrigation at 67 % ETc was associated with reduced plant water status, leaf gas exchange and plant growth, although marketable fruit yield at 67 % ETc was similar to that at 100 % ETc and 133 % ETc in both growing seasons. Fruit sunscald incidence decreased as the irrigation level increased while blossom-end rot incidence remained unaffected. After harvest, rates of fruit water loss, fruit transpiration and fruit skin permeance decreased at increased irrigation level. Elemental analyses indicated an increase in fruit mineral content with increased irrigation level. Overall, the present study showed that, compared to irrigation at 100 % ETc, deficit irrigation level at 67 % ETc had no impact on fruit yield and quality despite the reductions in plant water status, plant growth and leaf gas exchange. Irrigation above 100 % ETc did not result in increased plant growth and fruit yield, thus irrigating beyond this level may not be sustainable.

The Mobility Transition in Health Professional Emigration

Abstract Introduction Human resources for health (HRH) emigration is a topic of great concern to policymakers. In what is called the “mobility transition”, emigration rates for the general population follow an inverted U-shaped curve, with migration rising at a positive relationship to GDP/capita until source countries reach a GDP/capita of $7,000 or more, after which emigration rates fall. It is unclear whether HRH emigration trends follow a similar pattern. Methods We drew OECD-destination physician and nurse emigration data from the OECD.Stat database from 2000-2016 and charted it against real GDP/capita (2011 $ international). We censored data from small island states and country-years with known coups or conflicts. We fit a mixed-effects model testing for a quadratic (U-shaped) relationship between the natural log of real GDP/capita and annual emigration flows, controlled for source country physician/nurse density and year. Results We drew data from 145 sending countries and 28 destination countries over 17 years. Scatter and fitted trend plots showed a regular, not inverted, U-shaped distribution of physician/nurse emigration rates, with low-income countries represented on the left end of the curve (with declining emigration with increasing GDP/capita) and high income, European nations represented on the rightmost end (with rising emigration with increasing GDP/capita) after an inflection point around $7,000 GDP/capita. Model estimates demonstrated a significant positive quadratic relationship between the natural log of GDP/capita and physician (p = 0.005) but not nurse emigration rates when controlled for other variables. Conclusions There appears to be a mobility transition in HRH emigration rates, with an increase in HRH emigration with rising GDP/capita in countries with greater than $7,000 GDP/capita. Of note, some European nations have emigration rates of similar magnitude to low-income African nations, likely due to relatively relaxed EU mobility regulations. Key messages Physician Emigration Trends follow a U-shaped transition with elevated rates in low- and high-income countries and depressed rates in middle income countries. Some European nations have emigration rates similar to low-income African/Asian countries.

Dietary supplementation with canthaxanthin and 25-hydroxycholecalciferol has beneficial effects on bone and oxidative metabolism in European quail breeders

This study aimed to investigate the effect of supplementation with canthaxanthin (Cx) and 25-hydroxycholecalciferol (25-OH-D3) on the production performance, egg quality, bone mineral content, blood biochemical parameters, and antioxidant status of European quail breeders. Two hundred and forty quail breeders were distributed in a completely randomized design with 5 diets and 8 replicates of 4 females and 2 males were used. All quail breeders received one of 5 diets: basal diet (containing 2,000 IU vitamin D3) or the same diet supplemented with 3 ppm Cx and 34.5 μg 25-OH-D3, 6 ppm Cx and 69 μg 25-OH-D3, 9 ppm Cx and 103.5 μg 25-OH-D3, or 12 ppm Cx and 138 μg 25-OH-D3. Production performance and internal and external egg quality parameters were not influenced by diet. Eggshell dry weight decreased linearly with increasing supplementation levels, and eggshell ash and calcium content increased quadratically. Plasma phosphorus, calcium, and ionic calcium levels in females and plasma ionic calcium levels in males showed a positive quadratic response to dietary supplementation. Femoral and tibiotarsal dry weight and calcium content were influenced by diet. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity in the liver of males and females and in the serum of females showed a positive quadratic relationship with Cx and 25-OH-D3 levels, whereas the malonaldehyde concentration showed a negative quadratic relationship. DPPH scavenging activity in the serum of male quail increased linearly with supplementation. There was a positive quadratic effect on superoxide dismutase gene expression and a positive linear effect on glutathione peroxidase 7 gene expression, suggesting that dietary enrichment with Cx and 25-OH-D3 might help protect spermatozoa against oxidative damage. The dietary supplement was pro-oxidative at high concentrations (above 9 ppm Cx). The results indicate that diets with adequate levels of Cx and 25-OH-D3 have a beneficial effect on calcium and phosphorus metabolism as well as on the antioxidant defense system. We recommend supplementing European quail breeders in the laying period with 6 ppm Cx and 69 μg 25-OH-D3.

An estimation of the dietary long-chain n-3 polyunsaturated fatty acids levels for optimum growth and feed utilisation for large Yellowtail Kingfish (Seriola lalandi)

Understanding optimal dietary long chain n-3 polyunsaturated fatty acid (LC n-3 PUFA) levels for aquaculture species is vital to sustainably and economically utilise fish oil. The optimum dietary LC n-3 PUFA level for large Yellowtail Kingfish (Seriola lalandi; YTK) was unknown. In this 84 day study, the growth, feed efficiency and health of YTK (2.67 kg) fed graded levels of dietary fish oil, using poultry oil as the replacement, were investigated to determine the practical optimal dietary LC n-3 PUFA levels. Eight diets were formulated to contain graded dietary LC n-3 PUFA levels that ranged from 0.753 to 2.950 g 100 g−1. There was a moderate positive quadratic relationship between dietary LC n-3 PUFA and specific growth rate (SGR) (R2 = 0.5697; P < .001). Based on the SGR, the optimal level of LC n-3 PUFA (ymax) was 2.12 g 100 g−1. This equated to a LC n-3 PUFA daily intake of 191 mg kg−1 d−1. There was no improvement in SGR by increasing LC n-3 PUFA levels above 2.39 g 100 g−1. There was a moderate negative quadratic relationship between dietary LC n-3 PUFA level and feed conversion ratio (FCR) (R2 = 0.5758; P < .001). The FCR of YTK improved as dietary LC n-3 PUFA levels increased from 0.75 to 2.14 g 100 g−1. Based on the FCR, the optimal level of LC n-3 PUFA (ymin) was 2.26 g 100 g−1. This equated to a LC n-3 PUFA daily intake of 203 mg kg−1 d−1. The 95% CI for each response variable ranged between 1.90 and 2.33 g 100 g−1 and 1.93 to 2.58 g 100 g−1 for SGR and FCR, respectively. Apart from minor alterations to hindgut villus branching, LC n-3 PUFA level had no significant impacts on hind or midgut histology (P > .05). Based on SGR and FCR response variables it was estimated that the optimal dietary level of LC n-3 PUFA for large YTK was between 2.12 and 2.26 g 100 g−1.

Donor body size and sex steroid hormones impact germ cell production for creation of xenogenic catfish

Xenogenesis is emerging as an innovative technology for hybrid catfish (channel catfish, Ictalurus punctatus ♀ × blue catfish, I.furcatus ♂) production, where primordial germ cells (PGC), spermatogonial stem cells (SSCs) or oogonial stem cells (OSCs) are transplanted into infertile host species such as triploid fish to produce xenogens. Currently, donor cells are collected from randomly selected immature fish without having prior knowledge regarding the best donor stage, which is critical to increase the efficiency and success of germ cell transplantation in catfish breeding. Therefore, the current study was carried out with the objective of determining the relationships between quantity of stem cells, total length (TL), total weight (TW), and the level of androgens [testosterone (T) and 11-ketotestosterone (11-KT)] in blue catfish (donor fish). Positive quadratic relationships were observed between TL and the number of extracted live SSCs (r2 = 0.51; P < .0001) as well as TW and the number of live SSCs (r2 = 0.37; P < .0001), revealing that a TL of 25 to 39.9 cm and TW of 100 to 499.9 g, yield the highest number of extracted live SSCs. Similar to the findings from males, TL (r2 = 0.76; P < .0001) and TW (r2 = 0.67; P < .0001), also revealed positive quadratic relationships to the number of extracted live OSCs, where 25 to 39.9 cm and 200 to 600 g females yielded the greatest number of extracted live cells. Positive quadratic relationships were also detected between levels of T (r2 = 0.60; P < .0001), 11-KT (r2 = 0.60; P < .0001) and number of extracted live SSCs in male catfish, where 49 to 51.9 pg/mL of serum T and 37 to 48.9 pg/mL of 11-KT yielded the maximum number of live SSCs. Overall, these relationships between the quantity of stem cells and body size as well as the profile of sex steroid hormones reveal promising results as reliable biomarkers to enhance the efficiency of germ cell transplantation. These results can also be used to make precise predictions on the number of stem cells at a certain body size without sacrificing precious fish housed in living genetic repositories.

Positive emotions despite substantial burden: The alchemy of haemophilia caregiving.

Qualitative interviews when developing the haemophilia caregiver impact measure© (HCI) documented the importance of capturing the positive aspects of caregiving, not just the negative. The present study thus investigates the construct underlying the positive emotions HCI subscale and tests models proposing a more comprehensive way of thinking about this construct. Secondary analysis was implemented on longitudinal web-based survey data (n=323) from haemophilia A or haemophilia B caregivers. Person-reported outcomes (PROs) included the HCI, the PROMIS-10 and Ryff psychological well-being subscales. Predictors included caregiver demographics; patient haemophilia characteristics; exercise; adherence; and quality-of-life (QOL) appraisal processes as measured by the brief appraisal inventory (BAI) which yields composite scores assessing awareness of challenges, fulfillment and growth, stay positive, social comparison and interpersonal problem-solving. Second-order factor analysis, structural equation modelling and residual modelling were implemented. A structural equation model fit the data well that contained bifactor representation of well-being with ageneral factor comprised of environmental mastery, positive relations with others, physical functioning and emotional functioning. Positive emotions was modelled as a component of well-being, with a unique component ('Alchemy') characterized by its associations with stay positive, and awareness of challenges appraisals, and difficulty paying bills. Alchemy had positive linear relationships with the first two, and a positive quadratic relationship with difficulty paying bills. Adopting positive-focused ways of thinking about one's life limitations may transform the negatives of haemophilia caregiving into something positive. Such cognitive habits reflect an awareness and acceptance of the limitations imposed by haemophilia caregiving.

Age and Gender Specific Thyroid Hormones and Their Relationships with Body Mass Index in a Large Chinese Population.

ObjectivesTo investigate the associations of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) with body mass index (BMI) and the effect of age and gender on these relationships in a large Chinese population.MethodsA total of 97,997 individuals from a health examination center were selected. The medians (25th and 75th) of TSH, FT3 and FT4 were used to explore the trends based on gender, 10-year age groups and BMI. The relationships of TSH, FT3 and FT4 with BMI were assessed by generalized additive models (GAM) along with adjusting the effect of age and gender.ResultsAfter applying our exclusion criteria, 77,991 euthyroid participants (45,428 males and 32,563 females) were analyzed. The medians of TSH level based on BMI groups were significantly higher in female participants than those in males in all age groups (P < 0.05), and the median FT3 level was lower in female subjects; however, there was no significant difference between male and female subjects in median FT4 level. The GAM analysis showed the non-linear positive association of TSH and FT3 with BMI, and these relationships were markedly influenced by age and gender. However, FT4 had a negative relationship with BMI, with neglectable effect of age and gender.ConclusionsTSH, FT3 and BMI have a non-linear and positive quadratic relationship after age and gender adjustment. FT4, however, has a negative non-linear relationship with BMI with neglectable influence of age and gender.

Empathy in informal dementia caregivers and its relationship with depression, anxiety, and burden

Background/Objective: Recent interventions aim to heighten informal caregivers’ empathy levels assuming that this will lead to better well-being. However, previous studies have explored linear associations between empathy and aspects of well-being and yielded mixed results. We hypothesized that quadratic models may be more fitting to describe these relationships. Method: A cross-sectional study, with two groups (201 informal caregivers, and 187 non-caregivers) was conducted. Participants completed questionnaires on cognitive and affective empathy, and depression, anxiety, and caregiver burden. AN(C)OVA's and multiple hierarchical regression analyses including linear and quadratic terms were used to analyze the data. Results: For caregivers, there was a negative quadratic relationship between depression and cognitive empathy, and a positive linear relationship between anxiety and affective empathy, irrespective of sociodemographic characteristics. For non-caregivers, there were positive quadratic relationships between depression and cognitive and affective empathy, and between anxiety and affective empathy. The empathy levels did not differ between the groups. Conclusions: While caregivers and non-caregivers had the same amount of empathy, the relationships between empathy and depression and anxiety differed between the groups. Interventions for informal caregivers could aim to heighten cognitive empathy and to lower affective empathy to diminish depression and anxiety symptoms.

Networks of collaborative alliances: the second order interfirm technological distance and innovation performance

Studies have typically focused on the relationship between technological distance between partners in alliances, and innovation performance, from a direct tie or dyadic perspective. This paper explores the ego network set up in order to disclose how the second order technological distance, which is the distance between the partner and the partner’s partner, affects the innovation performance of the focal firm. To accomplish it, the network of alliances is built using biotechnological joint patents. The main result of this research is the finding of a positive quadratic relationship between the innovative performance of firms and second-order technological distance. This result has two implications. The first one is that the innovative performance of each firm embedded in a network cannot be optimized simultaneously. The second one, is that firm’s decision makers should consider the second-order neighborhood of the focal firm to establish optimal alliance in terms of innovation and enhance firm’s competitive advantage. Overall, this research set a new perspective to understand and improve the role of individual firms in collaborative networks, and help to complement the dominant view emphasizing the role of indirect ties in order to innovate.