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Estimating technical efficiency at farm level when plot-level data are available
No full textAbstract Ownership of multiple plots by a farmer leads to hierarchical structure of data on production. Researchers use averaging of plot-level technical efficiency scores for computing the farm-level technical efficiency score. With Monte Carlo simulation, we checked the performance of averaging and that of the linear mixed effects model in estimating the true farm efficiency. We generated true efficiency scores under half-normal, normal, and skew-normal distributions of the farm-level random effect. Plot-level score averaging did not estimate the true efficiency. The linear mixed effects model preserved the ranking as well as estimated the true farm-level efficiency score
Chromite in main group pallasite meteorites: Accessory mineral tracing planetesimal differentiation
No full textAbstract Main group pallasite meteorites (PMG) are samples of an early, highly differentiated magmatic planetesimal dominated by olivine and metal‐sulfide‐phosphide assemblages with accessory chromite among other phases. This mineralogy reflects mantle‐ and core‐related reservoirs, but the relative contributions of each and the overall petrogenesis are obscured by high degrees of protolith melting. Here, we present new data on the chemistry of chromite in these meteorites and review previous datasets. The purely lithophile elements Mg and Al partition into chromite via (Mg,Fe)(Al,Cr) 2 O 4 and mainly reflect interactions with olivine and basaltic melt, respectively. Chromite cores are virtually always more aluminous than rims, and while MgO contents were likely reset during slow cooling, their Al 2 O 3 contents are more robust and were largely set during the period of silicate magmatism. Main group pallasite chromites display bimodality in Al 2 O 3 contents, with peak concentrations at ~7.7 wt% and below 6 wt%, which is unlike any other achondrite chromite population. Some chromites have very low Al 2 O 3 contents (~0.01 wt%) due to formation in the absence of silicate melt, that is, via exsolution of Cr from cooling liquid metal. High‐, low‐, and very low‐Al 2 O 3 chromites in these meteorites broadly reflect relict, prograde, and retrograde periods of planetesimal heating followed by cooling. The Al 2 O 3 contents of the chromites in many other achondrites and equilibrated chondrites are similar to the higher values in pallasites, with most greater than 3 wt%. This suggests that meteoritic chromite is a significant sink for 26 Al during its life as a heat source for planetesimal differentiation. To first order, it may be responsible for ~25%–50% (i.e., about one third) of heating in partially depleted mantles.Fonds Wetenschappelijk Onderzoek https://doi.org/10.13039/501100003130Alexander von Humboldt-Stiftung https://doi.org/10.13039/100005156Vrije Universiteit Brussel https://doi.org/10.13039/501100004418Belgian Federal Science Policy Office https://doi.org/10.13039/50110000274
Chimpanzees rationally revise their beliefs
No full textThe selective revision of beliefs in light of new evidence has been considered one of the hallmarks of human-level rationality. However, tests of this ability in other species are lacking. We examined whether and how chimpanzees ( Pan troglodytes ) update their initial belief about the location of a reward in response to conflicting evidence. Chimpanzees responded to counterevidence in ways predicted by a formal model of rational belief revision: They remained committed to their initial belief when the evidence supporting the alternative belief was weaker, but they revised their initial belief when the supporting evidence was stronger. Results suggest that this pattern of belief revision was guided by the explicit representation and weighing of evidence. Taken together, these findings indicate that chimpanzees metacognitively evaluate conflicting pieces of evidence within a reflective process.Editor’s summary The ability of humans to think rationally and weigh the evidence when making a choice is well known. Such decision making requires a metacognitive process in which an individual can evaluate an overall set of evidence and make the best supported choice. Whether other animals can also do this has been unknown. Schleihauf et al . tested whether our closest relatives, chimpanzees, were able to evaluate weak and strong evidence regarding the location of a food reward (see the Perspective by Hare). They found that the chimps correctly inferred the most rational location based on the strength of the evidence that they received about the reward’s location. —Sacha VignieriThe selective revision of beliefs in light of new evidence has been considered one of the hallmarks of human-level rationality. However, tests of this ability in other species are lacking. We examined whether and how chimpanzees ( Pan troglodytes ) update their initial belief about the location of a reward in response to conflicting evidence. Chimpanzees responded to counterevidence in ways predicted by a formal model of rational belief revision: They remained committed to their initial belief when the evidence supporting the alternative belief was weaker, but they revised their initial belief when the supporting evidence was stronger. Results suggest that this pattern of belief revision was guided by the explicit representation and weighing of evidence. Taken together, these findings indicate that chimpanzees metacognitively evaluate conflicting pieces of evidence within a reflective process.Editor’s summary The ability of humans to think rationally and weigh the evidence when making a choice is well known. Such decision making requires a metacognitive process in which an individual can evaluate an overall set of evidence and make the best supported choice. Whether other animals can also do this has been unknown. Schleihauf et al . tested whether our closest relatives, chimpanzees, were able to evaluate weak and strong evidence regarding the location of a food reward (see the Perspective by Hare). They found that the chimps correctly inferred the most rational location based on the strength of the evidence that they received about the reward’s location. —Sacha Vignier
Incentives for Information Revelation in a Supply Chain and the Bullwhip Effect
No full textGetting downstream firms in a supply chain to share private information about consumer demand with their suppliers is generally considered a prerequisite to dampening the bullwhip effect, that is, the amplification of demand shocks as they pass upstream in a supply chain. If downstream firms are reluctant to share their demand information, how can they best be incentivized to do so, and what does the optimal incentive scheme imply for the bullwhip effect and supply chain efficiency? We examine these questions by developing a supply chain model with asymmetric information, and show that the supplier should optimally follow a two-pronged strategy. One prong consists of the optimal incentive contract to induce information revelation. Information revelation requires a distortion in the downstream firm’s orders that makes them more responsive to demand shocks, which tends to strengthen the bullwhip effect. The other prong helps to reduce this distortion and dampen the bullwhip effect. It consists of getting the downstream firm to increase its initial order and stock up on inventory before it learns about demand. A larger initial order is sufficient to eliminate the bullwhip effect if demand shocks are not too persistent. Our results hold if the marginal production cost does not increase too quickly with output and the inventory holding cost is not too high
UAV-based multispectral image analysis revealed stay-green haplotypes in wheat specific for different soil nitrogen levels
No full textAbstract Background The so-called stay-green trait, a delay in onset and progression of leaf senescence, is associated with slower chlorophyll degradation and higher photosynthesis rates during maturation resulting in higher crop yields. Understanding the genetic and physiological basis of the stay-green trait and breeding cultivars with stable stay-green behaviour across a range of different nitrogen (N) conditions and specifically under low N availability can contribute to ensuring wheat yields and reducing N fertilizer application. The goal of this study was therefore to identify haplotypes associated with high stay-green capacity under different N availability conditions in wheat. A diverse set of 221 wheat cultivars was grown under three different N levels and phenotyped by uncrewed aerial vehicle (UAV)-based multispectral imaging to characterise genetic and environmental variation in stay-green. Haplotypes associated with stay-green were identified across N levels and specifically under low N availability. Results The plant senescence reflectance index (PSRI) calculated from multispectral images was identified as the most specific stay-green indicator allowing for differentiation of genotypic effects due to its greater sensitivity to senescence-related changes in pigment composition and its higher reliability. We found genetic variance for stay-green and a consistent genetic correlation between stay-green and grain yield at all imaging dates and N levels within the utilised diversity panel confirming its potential as a future breeding target. Haplotype analyses revealed two favourable major allele haplotypes present in 95% of the stay-green cultivars, i.e. the top 25% of the diversity set based on PSRI values, which significantly enhance stay-green performance and grain yield. In addition, we identified a favourable minor allele haplotype specifically associated with stay-green under low N availability and capable of further increasing stay-green and grain yield when stacked onto the two favourable major allele haplotypes. Conclusions The newly identified stay-green haplotypes can be further used for fine-mapping and identifying the underlying genes as well as for selecting for higher stay-green and grain yield. Thereby our results can contribute to improving our understanding of the complex genetic regulation underlying stay-green in different environments and to breeding new cultivars with stable performance across N levels or specifically under low N availability
Ixazomib maintenance therapy in transplant-eligible multiple myeloma: real-world evidence from three large German centers
No full textNot available
Electron spin dynamics during microwave pulses studied by 94 GHz chirp and phase-modulated EPR experiments
No full textAbstract. Electron spin dynamics during microwave irradiation are of increasing interest in electron paramagnetic resonance (EPR) spectroscopy, as locking electron spins into a dressed state finds applications in EPR and dynamic nuclear polarization (DNP) experiments. Here, we show that these dynamics can be probed by modern pulsed EPR experiments that use arbitrary waveform generators to produce shaped microwave pulses. We employ phase-modulated pulses to measure Rabi nutations, echoes, and echo decays during spin locking of a BDPA (1,3-bisdiphenylene-2-phenylallyl) radical at 94 GHz EPR frequency. Depending on the initial state of magnetization, different types of echoes are observed. We analyze these distinct coherence transfer pathways and measure the decoherence time T2ρ, which is a factor of 2–3 times longer than Tm. Furthermore, we use chirped Fourier transform EPR to detect the evolution of magnetization profiles. Our experimental results are well reproduced using a simple density matrix model that accounts for T2ρ relaxation in the spin lock (tilted) frame. The results provide a starting point for optimizing EPR experiments based on hole burning, such as electron–nuclear double resonance or ELectron–electron DOuble Resonance (ELDOR)-detected NMR
Probing the staying power of chemogenetics
No full textA study that monitored the expression and function of designer receptors called DREADDs in macaque monkeys for a period of three years demonstrates that they are effective in long-term studies of nonhuman primates
Clinical outcomes of 188 patients implanted with Med-El stapes prostheses
No full textAbstract Purpose This multicentric, retrospective study aimed to analyze the safety and effectiveness of the mAXIS Stapes Prosthesis, mLOOP Stapes Prosthesis, mZAM Stapes Prosthesis, and mFIX Stapes Prosthesis. Methods Patients underwent stapes surgery and implantation of a mAXIS Stapes Prosthesis, mLOOP Stapes Prosthesis, mZAM Stapes Prosthesis, or mFIX Stapes Prosthesis (MED-EL, Innsbruck, Austria). The clinical data was retrospectively analyzed. Follow-up examination included access to medical records (for adverse events) of the patients, ear microscopy and pure-tone audiometry to determine the post-operative pure tone average of the frequencies 0.5, 1, 2 and 3 kHz (PTA 4 ). The post-operative PTA 4 air bone gap (ABG) was used to evaluate the audiological outcome. A post-operative PTA 4 ABG ≤ 20 dB was defined as successful rehabilitation. A post-operative minimum and maximum follow-up period was not defined. Results 189 patients were implanted with a MED-EL stapes prosthesis mainly as treatment of hearing loss caused by otosclerosis. 188 (186 adults, 2 children; 57 conductive hearing loss (CHL), 131 mixed hearing loss (MHL)) patients were examined for adverse events (AEs). 168 (166 adults, 2 children, 51 CHL, 117 MHL) patients underwent audiological examination. Audiology: 110 (65.5%) patients achieved a post-operative PTA 4 ABG ≤ 10 dB. 154 (91.7%) patients achieved a post-operative PTA 4 ABG ≤ 20 dB and therefore successful rehabilitation. Individual bone conduction (BC) PTA 4 thresholds were stable in 159 (94.6%) patients. AEs: 12 (6.4%, adults only) patients had 13 AEs. Conclusion Clinical data demonstrated satisfactory audiological results after implantation of the mAXIS Stapes Prosthesis, mLOOP Stapes Prosthesis, mZAM Stapes Prosthesis, and mFIX Stapes Prosthesis. The MED-EL stapes prostheses are safe and effective. Trial registration number NCT05565339 (clinicaltrials.gov)
