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This paper shares results from a pedagogical experiment that assigns undergraduates to "cheat" on a final class essay by requiring their use of text-generating AI software. For this assignment, students harvested content from an installation of GPT-2, then wove that content into their final essay. At the end, students offered a "revealed" version of the essay as well as their own reflections on the experiment. In this assignment, students were specifically asked to confront the oncoming availability of AI as a writing tool. What are the ethics of using AI this way? What counts as plagiarism? What are the conditions, if any, we should place on AI assistance for student writing? And how might working with AI change the way we think about writing, authenticity, and creativity? While students (and sometimes GPT-2) offered thoughtful reflections on these initial questions, actually composing with GPT-2 opened their perspectives more broadly on the ethics and practice of writing with AI. In this paper, I share how students experienced those issues, connect their insights to broader conversations in the humanities about writing and communication, and explain their relevance for the ethical use and evaluation of language models. [ABSTRACT FROM AUTHOR]

This paper deals with the trade-off between conversion time and power in nW-power capacitance-to-digital converters (CDCs). The CDC used in this work operates at nW power and low voltage down to 0.3 V without the need for any additional circuitry, references, or voltage regulation. It is built on swappable oscillators and takes advantage of the delay-power flexibility of dual-mode logic. Its self-calibration corrects PVT changes and mismatches at any point in the chip lifecycle, doing away with the necessity for cutting during testing. A CDC's test chip in 180 nm demonstrates that its power consumption can be dynamically modified from 1.37 nW down to 418 pW at a conversion time down to hundreds of ms, making it suited for harvesting systems with a very tight power budget and changing power sources. [ABSTRACT FROM AUTHOR]

Researchers have shown that even an individual can produce the wisdom of the crowds, called "the wisdom of the inner crowd." However, the previous methods leave room for improvements in terms of efficacy and response time. This paper proposes a more efficient method, which required a short time, based on findings from cognitive and social psychology. The procedure is to ask participants to give two answers to the same question: first, their own estimate and, second, their estimate of public opinion. Experiments using this method showed that the averages of the two estimates were more accurate than the participants' first estimates. That is, the wisdom of the inner crowd elicited. In addition, we found that the method could be superior to other methods in terms of efficacy and convenience. Moreover, we identified the conditions where our method worked better. We further clarify the availability and limitations of using the wisdom of the inner crowd. Overall, this paper proposes an effective and short-time method for harvesting the wisdom of the inner crowd. [ABSTRACT FROM AUTHOR]

Non-integer orders for fractional differintegral based adaptive filtering are very useful for addressing the various levels of textural discrimination in any image. This paper addresses a novel contribution for image enhancement by harvesting the collective benefits of fractional-order differentiation (FOD) as well as fractional-order integration (FOI). A 2-D fractional-order (FO) "Differintegration" (FODI) based dual-operator is proposed for imparting "on-demand adaptive-filtering" through spatial masking for adaptive textural boosting along with contrast enhancement. In addition, FODI based adaptive filtering is also employed for improving the conventional Multiscale Retinex approach. Consequently, the second novel contribution in this paper is the proposed framework for Differintegration based Fractional-order Multi-scale Retinex (DFMSR) for effective reflectance channel computation. The proposed DFMSR module is readily compatible with other image pre-processing methods for effective suppression of airborne and/or illumination based visual imperfections. An optimal fractional-order two-dimensional adaptive filtering mechanism is proposed in this paper. The proposed model is highly modular. So, it can also be pipelined in parallel manner, along with any well-established state-of-the-art contrast enhancement approach. Total quality improvement for remotely sensed textural data is achieved in this work. Being highly modular, four different possible variants of proposed approach are also discussed in this draft, so that a generalized solution can be identified for overall quality improvement for diverse variety/domains of the visual data or images. [ABSTRACT FROM AUTHOR]

Purpose: This article demonstrates the possibility of energy harvesting by mistuned pendulums with torsional coupling. Two pendulums of different lengths with coils and magnets at the pivots are used as electromagnetic harvesters. The ambient energy source to the system is considered in the form of harmonic base excitations. Torsional coupling is achieved by connecting the pendulums with a torsional spring. The non-linearity of the underlying dynamics arises due to mechanical coupling and forcing amplitude. Numerical results are presented to analyze the performance of the pendulum energy harvester under different torsional coupling values. Method: The mathematical model of the electro-mechanical system with torsionally coupled pendulums under harmonic excitation is developed. The mistuning is introduced by two pendulums with different lengths l1 and l2. The coupling between them is achieved by a torsional spring of stiffness kc. These pendulums are connected to the shafts of the electromagnetic generators with a magnet attached to the pendulum as a rotor and coil as stator. Current i is generated due to electromagnetic induction whenever pendulum oscillates. The numerical and harmonic balance method analysis were carried out. Runge-Kutta integration was used for numerical analysis. The analysis was carried out to determine the effect of coupling, length and resistive coefficient. The bifurcation diagram and Poincare plots were used for dynamic analysis and cross recurrence plots for analysis of relations between pendulum harvesters. Results: The effect of coupling on harvester performance was carried out, the variation of maximum power and frequency band with coupling can be categorized into 3 zones. The ranges for Zone-I, II and III of maximum power are [0-0.059], [0.06-0.11] and above 0.11 respectively. In Zone-I total power and the total band are dominating over pendulum-1 and pendulum-2. In Zone-II, the performance of pendulum-2 is comparable with the total performance. In contrast, the performance of pendulum-1 is low. Saturation of maximum power and bandwidth can be observed in zone-III. Uncoupled pendulum-1 and 2 exhibits a periodic oscillation. A low amplitude quasi-periodic response of pendulum-1 and high amplitude quasiperiodic response of pendulum-2 can be observed for coupling of β = 0.04. Both pendulums exhibit high amplitude chaotic response at β = 0.07. The introduction of coupling induced nonlinearity in both pendulums. the amplitude and velocity also increased due to the quasi-periodicity and chaos induced in pendulums due to the coupling and better energy harvesting capabilities can be expected. The harmonic balance analysis indicates that there is a possibility of obtaining a high amplitude current at lower frequencies provided proper initial conditions are chosen. Conclusion: A twin electromagnetic pendulum energy harvester with torsional coupling is analyzed in order to optimize the efficient energy harvesting and study the energy harvester dynamics. The paper categorized the three distinct zones based on the coupling ratio β and length ratio α2. One can select parameters from these zones based on need. Zones-II and III are the most promising zones. If one wants to harvest broader energy Zone-II is preferable with harvesting only from the energy harvester with a low resonant frequency which in turn saves material cost. To harvest peak power one can, select Zone-III and harvest from both energy harvesters. The performance in the respective zones can be further enhanced by using optimal initial conditions to obtain high energy orbits at lower frequencies. The probability of obtaining high energy orbits decreases with an increase in the coupling ratio. The effect synchronization with coupling on energy harvesting plays an important role form magnitude and bandwidth point of view. The analytical results obtained by the Harmonic Balance Method are in good agreement with numerical results. [ABSTRACT FROM AUTHOR]

Automatic apple harvesting robots have received much research attention in recent years to lower harvesting costs. A fundamental problem for harvesting robots is how to quickly and accurately detect branches to avoid collisions with limited hardware resources. In this paper, we propose a lightweight, high-accurate and real-time semantic segmentation network, Bilateral U-shape Network (BUNet), to segment apple tree branches. The BUNet consists mainly of a U-shaped detail branch and a U-shaped semantic branch, the former for capturing spatial details and the latter for supplementing semantic information. These two U-shape branches complement each other, keeping the high accuracy of the Encoder-decoder Backbone while maintaining the efficiency and effectiveness of the Two-pathway Backbone. In addition, a Simplified Attention Fusion Module (SAFM) is proposed to effectively fuse different levels of information from two branches for pixel-by-pixel prediction. Experimental results show (on our own constructed dataset) that BUNet achieves the highest Intersection over Union (IoU) and F1-score of 75.96% and 86.34%, respectively, with minimum parameters of 0.93M and 11.94G Floating-point of Operations (FLOPs) in branch segmentation. Meanwhile, BUNet achieves a speed of 110.32 Frames Per Second (FPS) with input image size of 1280 × 720 pixels. These results confirm that the proposed method can effectively detect the branches and can, therefore, be used to plan an obstacle avoidance path for harvesting robots. [ABSTRACT FROM AUTHOR]

Recognition of the multiple types of value of marine resources is crucial to help design locally meaningful and sustainable management approaches for marine and coastal habitats. There is a lack of information on the amount of living marine resources harvested by coastal communities in many Pacific Island Countries and Territories (PICTs), as well as on their economic and non-economic value. This paper explores the monetary, subsistence, and sociocultural value of selected marine resources (finfish and invertebrates) in Kadavu province, Fiji, based on a household survey and semi-structured interviews conducted in 2019 within one specific district. The paper provides estimates of the annual catch and monetary value of marine resources harvested by local communities at both the district and provincial levels, derived from catch and effort information collected from fishers and gleaners in situ. It also highlights the importance of integrating the sociocultural significance of marine resources into future value assessments. [ABSTRACT FROM AUTHOR]

Key message: Greater embryo size in a large and carefully phenotyped mapping population was genetically associated with a greater number of longer seminal roots to increase grain yield in droughted field environments. Breeding modification of root architecture is challenging in field environments owing to genetic and phenotypic complexity, and poor repeatability with root sampling. Seeds from a large mapping population varying in embryo size were harvested from a common glasshouse and standardised to a common size before assessing in rolled germination paper at 12 and 20 °C for seedling growth. Differences in genotype means were large and heritabilities high (h2 = 0.55–0.93) indicating strong and repeatable genotypic differences for most root traits. Seminal roots 1 to 3 were produced on all seedlings, whereas growth of seminal roots 4, 5 and 6 was associated with differences in embryo size. Increases in seminal root number from 4 to 6 per plant were strongly, genetically correlated with increases in total seminal length (rg = 0.84, < 0.01). Multivariate analysis confirmed initiation and growth of seminal roots 1, 2 and 3, and of roots 4, 5 and 6 behaved as genetically independent (rPg = 0.15 ns) cohorts. Tails representing extremes in seedling root length and number were associated with significant differences in grain yield of up to 35% in droughted field environments but were not different in irrigated environments. Increases in grain yield were linked to greater lengths of seminal roots 4, 5 and 6 and were largely independent of plant height or development. This is the first report on the genetic relationship of seedling root architecture and embryo size, and potential in selection of seminal root size for accessing deep-soil moisture in droughted environments. [ABSTRACT FROM AUTHOR]

This paper investigates a discrete-time predator–prey model with predator harvesting. The stability analysis for different fixed points of the discretized model is shown briefly. In this study, different types of bifurcation and their normal forms are determined. As the prey harvesting and conversion rate of prey into predator are ecologically significant, the impact of theirs have been studied by choosing the bifurcation parameter. The system exhibits a sequence of bifurcations of codim-1 viz. Neimark–Sacker bifurcation and flip bifurcation (period-doubling) and codim-2 resonance bifurcation (1:2, 1:3 and 1:4) at a positive fixed point. For each bifurcation, by using the critical normal form coefficient method, various critical states are calculated under non-degeneracy conditions. Further, a detailed numerical simulation is presented for supporting the analytical findings. The bifurcation curves, phase plots and Maximum Lyapunov exponent (MLE) are drawn. The system exhibits a wide range of bifurcation, including periodic orbits, quasi-periodicity, resonance bifurcation and chaos. Moreover, it is shown that predator harvesting has a stabilizing effect on the dynamics of the model. The chaos that occurred in the system is reduced beyond the critical value of harvesting. The predator population goes extinct after crossing the threshold value of harvesting. This work reflects that the feasible upper bound of the harvesting rate for the species coexistence can be guaranteed. Further, a state feedback controller is employed to suppress the dense chaos in the discrete system. The control technique applied for codim-1 Neimark–Sacker bifurcation and codim-2 1:4 resonance bifurcation is instrumental to reduce the complexity in the system. [ABSTRACT FROM AUTHOR]

The transition from conventional arable towards silvoarable systems can increase the delivery of ecosystem services. Nevertheless, the assessment of crop yield under agroforestry condition is crucial to evaluate of the reliability of these systems and to increase the knowledge base needed to support their design. Although the feasibility of poplar short rotation coppice (SRC) silvoarable alley-cropping systems has been widely investigated, few studies have addressed the agronomic response of crops intercropped with poplar SRC in narrow alleys, especially in Mediterranean environments. Thus, this paper treats the effects of SRC poplar rows on soybean and sorghum productivity in a 2-year rotation implemented in an alley-cropping system. A field experiment was carried out in 2018 and 2019 with the objective of measuring and evaluating effects of light availability variation, as affected by the growing rate of 2-year coppice cycle poplar SRC rows, and the soil characteristics on soybean-sorghum and sorghum–soybean rotations. Above-ground biomass, grain yield and crops residue showed a significant reduction in the tree–crop interface up to 74% and sorghum proved to be less tolerant to light reduction compared to soybean. Our results demonstrated that light is the most important factor for sorghum cultivation, despite grain yield was also influenced by the soil characteristics such as pH, while soybean is affected also by soil moisture and water retention capacity. The design of crop rotation in an SRC-based agroforestry system needs to consider the different agronomic performance of different crops and the harvest cycle of tree rows. [ABSTRACT FROM AUTHOR]

Coral reefs provide refuge for prey and are important for the preservation of an oceanic ecosystem. However, they have been experiencing severe destruction by environmental changes and human activities. In this paper, we propose and analyze a tri-trophic food chain model consisting of coral, Crown-of-thorns starfish (CoTS), and triton in deterministic and stochastic environments. We investigate the effects of harvesting in the deterministic system and environmental noises in the stochastic system, respectively. The existence of possible steady states along with their stability is rigorously discussed. From the economic perspective, we examine the existence of the bionomic equilibrium and establish the optimal harvesting policy. Subsequently, the deterministic system is extended to a stochastic system through nonlinear perturbation. The stochastic system admits a unique positive global solution initiating from the interior of the positive quadrant. The long-time behaviors of the stochastic system are explored. Numerical simulations are provided to validate and complement our theoretical results. We show that over-harvesting of triton is not beneficial to coral reefs and modest harvesting of CoTS may promote sustainable growth in coral reefs. In addition, the presence of strong noises can lead to population extinction. [ABSTRACT FROM AUTHOR]

In the Antarctic, the whale population had been reduced dramatically due to the unregulated whaling. It was expected that Antarctic krill, the main prey of whales, would grow significantly as a consequence and exploratory krill fishing was practiced in some areas. However, it was found that there has been a substantial decline in abundance of krill since the end of whaling, which is the phenomenon of krill paradox. In this paper, to study the krill–whale interaction we revisit a harvested predator–prey model with Holling I functional response. We find that the model admits at most two positive equilibria. When the two positive equilibria are located in the region { (N , P) | 0 ≤ N < 2 N c , P ≥ 0 } , the model exhibits degenerate Bogdanov–Takens bifurcation with codimension up to 3 and Hopf bifurcation with codimension up to 2 by rigorous bifurcation analysis. When the two positive equilibria are located in the region { (N , P) | N > 2 N c , P ≥ 0 } , the model has no complex bifurcation phenomenon. When there is one positive equilibrium on each side of N = 2 N c , the model undergoes Hopf bifurcation with codimension up to 2. Moreover, numerical simulation reveals that the model not only can exhibit the krill paradox phenomenon but also has three limit cycles, with the outmost one crosses the line N = 2 N c under some specific parameter conditions. [ABSTRACT FROM AUTHOR]

In this paper we propose an object detector based on deep learning for scanning samples of table olives. For the construction of the system we have used a Mask R-CNN neural network. This network is able to segment the image providing a mask for each of the olives in the sample from which we can obtain the calibre of the object. In addition, the system is able to measure the degree of ripeness of the olives classifying them as green, semi-ripe and ripe, and identifying those fruits that are defective due to disease or damage caused by the harvesting process. The proposed system achieves success rates of 99.8% in the detection of olive fruits in photograms, 93.5% in the classification of fruit by ripeness and close to 80% in the detection of defects. [ABSTRACT FROM AUTHOR]

The aim of this study was to measure and model the fuel consumption of cut-to-length (CTL) logging machinery in cutting and forwarding under Nordic harvesting conditions, and to clarify which factors had the greatest effect on the fuel consumption. In addition, the total annual fuel consumption and CO2eq emissions were calculated for CTL logging operations in Finland in 2020. The data were collected during a long-term follow-up study on the fuel consumption of harvesters and forwarders conducted between March 2018 and April 2019. The fuel consumption data were obtained from a total of 16 harvesters and 13 forwarders equipped with digital flow metres featuring an accuracy of ± 1% of the fuel volume measured. The engine power of the forest machines explained most of the hour-based fuel consumption. Correspondingly, the harvesting conditions of the forest stand best explained the cubic-metre-based fuel consumption. The fuel consumption of CTL logging operations (cutting and forwarding) averaged 1.4 L m−3 in final felling, and 3.1 and 2.2 L m−3 in first and later thinning, respectively. There was a large variation in the cubic-metre-based fuel consumption between individual machines, both for harvesters and forwarders. The total calculated fuel consumption in Finnish CTL operations in 2020 was 126.6 million L, with the calculated CO2eq emissions totalling 334,209 t (i.e. 5.7 kg m−3). Several measures to accelerate fuel and energy efficiency and reduce CO2eq emissions in CTL logging operations are discussed in the paper. [ABSTRACT FROM AUTHOR]

In this paper, a single-species stochastic population model is considered in the presence of density-dependent proportional harvesting. The stochastic model is considered to include the effects of fluctuation in the predation rate and environmental variability. Coloured cross-correlated Gaussian coloured noises are used to generate stochastic fluctuations. Steady-state probability distribution function and stationary potential are determined using the approximate Fokker–Planck equation. Phenomenological bifurcation analysis and mean first passage time have been computed. The average population density in the outbreak state is calculated using normalised probability distribution of the outbreak state. The species outbreak control strategy has been proposed. The key observations of this study are the negative cross-correlation strength-induced noise enhanced stability (NES) phenomenon and the environmental stochasticity-induced resonant activation (RA) phenomenon. Bistable to monostable phase regime shift is observed to depend on the environmental stochasticity whereas monostable to bistatble phase regime shift is observed to depend on correlation time of the environmental stochasticity. [ABSTRACT FROM AUTHOR]

The results for the spatially lagged carnivore regressors have been omitted from the SDM column given that none are statistically different from zero Acknowledgements We are grateful to two anonymous reviewers for their contributions to improve the quality of this paper. [Extracted from the article]

In this paper, MoS2 nanosheets were prepared and deposited on BiOBr microflowers through deposition-hydrothermal strategy. MoS2 exhibited a string of nanosheets with wrinkled layer outlook, and MoS2/BiOBr composites displayed a micro-flower morphology with the diameter of 2-3 μm. Visible-light harvesting performance was significantly improved in the region of 400-600 nm for MoS2/BiOBr. The obtained MoS2/BiOBr samples exhibited tremendous enhanced catalytic activity, which could degrade 92.96% of tetracycline and 90.31% of levofloxacin within 70 min. The photo-generated holes and ⋅OH radicals played the dominant roles in the whole photocatalytic decomposition process. Based on the analysis of DRS, BET, PL, and electrochemical results, the remarkably improved photocatalytic performance may be ascribed to the synergistic effect of strong visible-light harvesting ability, enhanced BET surface area, and faster separation or transfer efficiency of photo-generated charges. [ABSTRACT FROM AUTHOR]

The paper attempts to determine the best storage conditions for green and roasted coffee beans. Coffee beans were processed in various ways—some of them were washed or left in their natural state after harvesting, then they were stored in two types of packaging with different permeability, i.e. jute bag and GrainPro polymer bag, ensuring stable conditions in three temperature chambers, i.e. − 10, 10 and 20 °C. The grains treated in this way were evaluated after 3, 6, 9, and 12 months. The selection of the analyzed parameters (in roasted coffee—cupping and 3 selected volatile organic compounds; in green coffee—average water activity, content of volatile fatty acids, 6 selected volatile organic compounds) was to monitor the ongoing processes, and thus the qualitative changes taking place in grains. The research shows that grain stored at 20 °C ages the fastest. Grains stored in − 10 °C and 10 °C chambers perform similarly well. The evaluation of the parameters shows that among the grains stored in these two chambers, the method of grain processing (Natural/Washed) had a greater impact on the results, while the type of packaging did not differentiate the grains to such a significant extent. [ABSTRACT FROM AUTHOR]

This paper is about shipping runtime verification to the masses. It presents the crucial technology enabling everyday car owners to monitor the behaviour of their cars in-the-wild. Concretely, we present an Android app that deploys rtlola runtime monitors for the purpose of diagnosing automotive exhaust emissions. For this, it harvests the availability of cheap Bluetooth adapters to the On-Board-Diagnostics (obd) ports, which are ubiquitous in cars nowadays. The app is a central piece in a set of tools and services we have developed for black-box analysis of automotive vehicles. We detail its use in the context of real driving emission (rde) tests and report on sample runs that helped identify violations of the regulatory framework currently valid in the European Union. [ABSTRACT FROM AUTHOR]

Arid region water reservoirs have different characteristics and solutions from humid regions with the most water shortage in the world socio-economically. This paper outlines possible implementation methodologies, procedures and guidance for water storage in natural and artificial reservoirs for better operation and management rules taking into account the impacts of climate change. The literature is full of methodological applications regarding the impact of climate change on the hydro-meteorological records, but the same is not available in reservoirs (surface and underground), which is the scope of this paper. In addition, reservoir structures offer the necessary mitigation and adaptation activities against the effects of climate change to design, construct, maintain, operate or increase their existing capacity. To increase groundwater reservoir capacity in local aquifers, precipitation, associated flooding and flash flooding should be diverted to artificial groundwater recharges through precipitation and surface runoff harvesting activities. Definitions of fully or partially penetrating underground dams are also explained. The real groundwater feeding application is offered from the Kingdom of Saudi Arabia as arid region representative. Finally, a series of recommendations are presented for the future design and management of reservoirs. [ABSTRACT FROM AUTHOR]

Nowadays, Combine Harvesters are the most commonly used device for harvesting crops; as a result, a large amount of plant material and crop residue is concentrated into a narrow band of plant material that exits the combine, challenging the residue management task. This paper aims to develop a crop residue management machine that can chop paddy residues and mix them with the soil of the combined harvested paddy field. For this purpose, two important units are attached to the developed machine: the chopping and incorporation units. The tractor operates this machine as the main source, with a power range of about 55.95 kW. The four independent parameters selected for the study were rotary speed (R1 = 900 & R2 = 1100 rpm), forward speed (F1 = 2.1 & F2 = 3.0 Kmph), horizontal adjustment (H1 = 550 & H2 = 650 mm), and vertical adjustment (V1 = 100 & V2 = 200 mm) between the straw chopper shaft and rotavator shaft and its effect was found on incorporation efficiency, shredding efficiency, and trash size reduction of chopped paddy residues. The incorporation of residue and shredding efficiency was highest at V1H2F1R2 (95.31%) and V1H2F1R2 (61.92%) arrangements. The trash reduction of chopped paddy residue was recorded maximum at V1H2F2R2 (40.58%). Therefore, this study concludes that the developed residue management machine with some modifications in power transmission can be suggested to the farmers to overcome the paddy residue issue in combined harvested paddy fields. [ABSTRACT FROM AUTHOR]

Existing landscape features, such as field boundary hedgerows, can contribute to food, fodder, material, and energy production for an EU bio-based circular economy. Recent trials undertaken by the project team in the UK demonstrated that hedgerows can be managed to produce woodfuel of a quality that meets industry standards. However, to be attractive to farmers, woodfuel production from hedgerows must be profitable. This paper uses the FarmSAFE model to undertake a financial assessment with data generated from these trials. The net present value of a standard hedgerow management method (flailing every 2 years) was compared with those from alternative hedgerow management scenarios for woodfuel production over a 60 year time horizon. Using data from the hedgerow trials, the results showed that coppicing hedgerows for woodfuel production could provide a profit to the farmer. The sale of woodchips into an off-farm market was found to be profitable if harvesting with tree shears (medium scale harvesting capacity) or a Bracke felling head (large scale harvesting capacity), but chainsaw harvesting (small scale harvesting capacity) was unprofitable. When considering the use of woodchips on farm to replace purchased woodchip or heating oil, the financial benefit to the farmer increased. Sensitivity analyses showed that the use of medium scale machinery (tree shears) made the hedgerow enterprise most resilient to changes in prices, grants, and costs. This scale of machinery is appropriate for local energy production whilst also being affordable to farmers and local contractors. [ABSTRACT FROM AUTHOR]

India has committed to reducing the emissions intensity of GDP by 33–35% from the 2005 level by 2030 in alignment with objectives of the Paris Agreement. This will require a significant reduction in greenhouse gas (GHG) emissions from the food and land-use sector. In this paper, we construct three potential pathways for India to achieve its emissions target by 2050 involving moderate ambitions of mitigation action (BAU), moderate ambitions combined with achieving healthy diets (BAU + NIN), and high levels of mitigation action inclusive of healthy diets (SUSTAINABLE). Using an integrated accounting tool, the FABLE Calculator, that harmonizes various socioeconomic and biophysical data, we project these pathways under the conditions of cross-country balanced trade flows. Results from the projections show that the demand for cereals will increase by 2050, leading to increased GHG emissions under BAU. Under the SUSTAINABLE pathways, GHG emissions will decrease over the same period due to reduced demand for cereals, whereas significant crop productivity and harvest intensity gains would lead to increased crop production. The exercise reveals the indispensability of healthy diets, improved crop, and livestock productivity, and net-zero deforestation in achieving India's mid-century emission targets from the agriculture sector. [ABSTRACT FROM AUTHOR]

Four rare discoveries from the coast of Antalya provide evidence that divers were active in the area during the Hellenistic-Roman Periods as has been indicated in many different sites of the Mediterranean basin in the same period. The first discovery was a stone tool found off the ancient Cilicia Region on Alanya-Antalya coastline of Southern Turkey in 2011. The second find was discovered in 2019, off the coast of ancient Lycia region, alongside the shores of the Three-Islands of Kemer-Antalya. This second artifact is a more familiar ring-shaped object made of lead. It is similar to objects found off the coast of Israel and identified as "salvage rings." These two objects were found as lone objects, neither associated with a shipwreck nor within a specific context. These were followed by two other ring-shaped objects found in 2021, again off the ancient Lycia region, one in Kaş and the other one on the Kekova coastline. Both of these objects are marble weights and akin to the one which had been found on the coast of Caesarea, Israel and named as a "salvaging ring" in the literature. These two marble rings have been found near shipwrecks. One surmises they were possibly used by divers to retrieve some sunken cargo. All four finds could be examples of diver weights that were used by ancient divers for reaching the desired depths faster for salvage operations or other diving activities such as harvesting sponges and oysters. Artifacts of these sorts found on the seabed are extremely rare. Along the entire 640 km Antalya coastline, over a time span of two decades, these are the only four recovered objects. In searching for the history of these artifacts and their originally intended purposes, a study is conducted with similar objects from different sites of the Mediterranean. This paper concludes with a recent experiment to test whether the artifacts could have been diver weights. [ABSTRACT FROM AUTHOR]

The detection of cherry tomatoes has a great significance for robotic harvesting. However, uneven environment conditions, such as branch and leaf occlusion, cluster of fruits, and so on, have made the cherry tomatoes detection very challenging. This paper proposes an effective cherry tomato detection algorithm called YOLOX-Dense-CT to solve these problems. To be specific, the DenseNet network is treated as the basic backbone of the original YOLOX to make the whole network suitable for the cherry tomatoes. Moreover, the convolutional block attention module (CBAM) attention mechanism is applied to make the features from the backbone more fused with the Neck part. As suggested by the experimental results, the proposed YOLOX-Dense-CT model is effective in detecting cherry tomatoes, with the mean average precision (mAP) reaching 94.80%, which is 4.02% higher than the original YOLOX-L model. Meanwhile, the number of parameters is only 34.6 M, which is 19.6 M lower than the YOLOX-L. Furthermore, the YOLOX-Dense-CT is compared to general target detection models and it has the best detection performance. In summary, the proposed method can well meet the requirements of high accuracy detection and provide a strategy for the cherry tomato detection system. [ABSTRACT FROM AUTHOR]

The relationship between prey and predator has been modelled, analysed from the early nineteenth century by considering different types of functional responses and ecological effects. Harvesting of predator in a prey-predator system for controlling their dynamics has been receiving considerable attention from both ecological and economical points of view. A lot of theoretical work has been done on harvesting and reveals that harvesting has a significant impact due to its ecological and economical importance. The fear of prey due to the appearance of predators in the ecological system also plays an important role in drawing the shape of the dynamics of the interacting system. Another important fact, in reality, the reproduction of predator is not instantaneous after the consumption of prey. A constant time lag is necessary for each organism. In this paper, we have investigated the dynamics of a delayed prey-predator model with Holling type III functional response and fear of prey in the natural birth rate. The predator is assumed to be economically significant and harvested linearly. The positivity, boundedness, local stability of equilibrium points and local bifurcation (Transcritical, Hopf bifurcation) of the non-delayed system is established here. We have discussed the local and global stability of the interior equilibrium point in presence of delay. In terms of the delay parameter, the system undergoes through a Hopf bifurcation and we determine in which direction the Hopf bifurcation will go. We carried out some numerical simulations illustrate the theoretical findings using the MAPLE and MATLAB software. Finally, we have drawn some concluding remarks. [ABSTRACT FROM AUTHOR]

In this paper, a generalized population model with delays and harvesting term is studied, which includes some well-known models, such as Gilpin–Ayala competitive model and Logarithmic model. By a suitable Lyapunov function and the Banach fixed point theorem, we obtain the existence and uniqueness of globally attractive pseudo almost periodic solution of the model and prove its permanence. Some examples and numerical simulations are given to illustrate the feasibility and usefulness of the model and results. [ABSTRACT FROM AUTHOR]

In this paper an ecological model consisting of prey–predator–scavenger involving Michaelis–Menten type of harvesting function is proposed and studied. The existence, uniqueness and uniformly bounded of the solution of the proposed model are discussed. The stability and persistence conditions of the model are established. Lyapunov functions are used to study the global stability of all equilibrium points. The possibility of occurrence of local bifurcation around the equilibrium points is investigated. Finally an extensive numerical simulation is carried out to validate the obtained analytical results and understand the effects of scavenger and harvesting on the model dynamics. It is observed that the proposed model is very sensitive for varying in their parameters values especially those related with scavenger and undergoes different types of local bifurcation. [ABSTRACT FROM AUTHOR]

This paper focuses on a Gilpin–Ayala growth model with spatial diffusion and Neumann boundary condition to study single species population distribution. In our heterogeneous model, we assume that the diffusive spread of population is proportional to the gradient of population per unit resource, rather than the population density itself. We investigate global well-posedness of the mathematical model, determine conditions on harvesting rate for which non-trivial equilibrium states exist and examine their global stability. We also determine conditions on harvesting that leads to species extinction through global stability of the trivial solution. Additionally, for time periodic growth, resource, capacity and harvesting functions, we prove existence of time-periodic states with the same period. We also present numerical results on the nature of nonzero equilibrium states and their dependence on resource and capacity functions as well as on Gilpin–Ayala parameter θ . We conclude enhanced effects of diffusion for small θ which in particular disallows existence of nontrivial states even in some cases when intrinsic growth rate exceeds harvesting at some locations in space for which a logistic model allows for a nonzero equilibrium density. [ABSTRACT FROM AUTHOR]

This research examines the implications of rainwater harvesting structure hapa in the Bankura district of West Bengal, India. The paper finds that proper management and harvesting of surface and subsurface runoffs in hapas can facilitate groundwater recharge and increase both net irrigated area and moisture in soil leading to higher cropping intensity and yield in dryland areas. However, dissected plateau and residual hillocks can reduce irrigation efficiency of hapas. Although sprinkler or drip irrigation along with cultivation of drought and lateritic resilient, low moisture crop can help in coping up with geophysical and climatic vulnerability, appropriate crop diversification is also necessary. There is also a need for regular maintenance and desiltation of hapas. The water user groups should play an active role for this, especially for hapas in common land. Further, scientific guidance is necessary for designing appropriate structure of hapas in different geo-physical conditions. [ABSTRACT FROM AUTHOR]

A stochastic four species food-chain model is proposed in this paper. Here, artificial harvest in each species and the effect of time delay for interaction between species are considered, which makes the model more applicable in real situations. Specifically, we address the stochastic global dynamics behavior, including the existence of global positive solutions, stochastic ultimate boundedness, extinction with probability one, persistence in mean and global stability. The asymptotic stability in the probability distribution is obtained, and the criterion for the existence and non-existence of the optimal harvesting strategy is also derived. Furthermore, this paper can provide reference for the research of general n-species stochastic food-chain models. [ABSTRACT FROM AUTHOR]

"Access and allocation" is one of the five analytical problems identified as key for analysing earth system governance in the first Earth System Governance Science and Implementation Plan officially published in 2009. Ten years later and with a new Science and Implementation Plan in place, it is time to take stock. Therefore, this paper addresses the question: What does a decadal review of the Earth System Governance literature tell us about how to conceptualize and define access and allocation, what ethical norms and epistemologies underlie access and allocation research, and what does Earth System Governance scholarship reveal about the interplay between access and allocation and other norms? We find that: (a) there is a relatively small body of the Earth System Governance literature on access and allocation, albeit growing; (b) this literature is largely empirical and dispersed across a variety of topics; and (c) there is a diversity of ethical norms and principles emphasized in Earth System Governance scholarship, but the dynamics between different forms of access and related implications for allocation are relatively underexplored. In light of these findings and with a new Earth System Governance Science and Implementation Plan in place, this paper highlights key areas for further research and development. [ABSTRACT FROM AUTHOR]

The most valuable resource for sustaining life on earth is water. In dry and semi-arid areas, the problem of water scarcity can be resolved with the aid of fog collection techniques employing fog collectors. Fog collection is greatly influenced by a variety of factors. Some are design parameters, while others depend on ambient circumstances. Geometry and the mesh's shade coefficient are important design factors that can be modified and have an impact on the rate at which fog collects in fog collectors. The shape of the mesh holes and the process used to create the mesh serve to identify geometry and measure the shade coefficient. In this paper, a straightforward mathematical technique is proposed to make it easier to calculate the shade coefficient of various mesh shapes used in fog harvesting and to provide an approximation of the mesh volume and cost. Five alternative geometries were used: the rectangular mesh, square mesh, Raschel mesh, triangular mesh, and hexagonal mesh. The current simple method will facilitate the design of the fog mesh collector and can assist in achieving the ideal shade coefficient and most effective mesh geometry for fog harvesting. Rectangular meshes were solely used as an example to evaluate the results. Stainless steel rectangular meshes with various shade coefficients were tested for fog collection, and the amount of water collected by each mesh varied. It was concluded that the optimum shade coefficient ranged 50–60% for fog collection. [ABSTRACT FROM AUTHOR]

RF harvesting has attracted the attention to be used as a power source for low-power systems like IoT, wireless sensor nodes, and wearable devices. The RF rectifier has been the bottleneck in achieving efficient RF-DC systems. This paper presents a new CMOS RF-DC converter design based on a body-control approach to control the ON & OFF states of the transistors. The design is constructed using the cross-coupled differential-drive (CCDD) rectifier. The design uses less number of capacitors compared to some reported designs in the literature, which saves more active area. The proposed design has been implemented using 0.18 μ m TSMC CMOS technology and verified using Cadence Virtuoso EDA. Thanks to the body-control scheme, the design achieves wide power dynamic range (PDR) of 20 dBm and a peak power conversion efficiency (PCE) of 71.6% for one stage of the proposed design. In addition, the proposed design obtains an output voltage of 0.47 V for 10 k Ω and −15 dBm input power. It occupies an area of 0.0054 mm 2 . The proposed structure is also implemented using three stages to achieve higher output voltage. The 3-stage rectifier achieves a PDR of 17.4 dBm and a peak PCE of 71.2%, and an output voltage of 1.6 V for 100 k Ω load and −14 dBm input power. Finally, the proposed RF-DC rectifier is compared with the state-of-the-art designs reported in the literature. [ABSTRACT FROM AUTHOR]

As an application of mathematics to engineering problems, this paper formulates a simple optimal stopping problem to decide the opening time of harvesting farmed fishery resources that maximizes an economic objective function. A sufficient condition for unique existence of the internal optimal opening time is provided and its concrete mathematical analysis is carried out. Comparative statics of the optimal opening time clearly reveals its dependence on the parameters of the farming environment. The problem is finally applied to analyzing management of a commercially important fishery resource in Japan. [ABSTRACT FROM AUTHOR]

A discrete cooperative model incorporating harvesting that takes the form is proposed and studied in this paper. By using the iterative method and the comparison principle of difference equations, a set of sufficient conditions which ensure the global attractivity of the interior equilibrium of the system is obtained. Numeric simulations show the feasibility of the main result. [ABSTRACT FROM AUTHOR]

The rapid increase in marine shipping activity in Inuit Nunangat (i.e. in settled land claim regions of Arctic Canada), propelled by climate change and international interest in Arctic maritime trade, has heightened concerns among Inuit communities about the risks that more ships could pose for sustainable and subsistence hunting, fishing, and gathering (berries, plants, eggs, etc.) (referred to as harvesting in this article) activities considered vital for cultural well-being and local livelihoods. As part of the Arctic Corridors and Northern Voices project, () a series of workshops, focus groups, and interviews were conducted in and with 14 communities across Inuit Nunangat that involved 133 marine experts and 59 youth community researchers. In this paper, we present the concerns identified by Inuit and local marine users about the risks of increased shipping activity specifically with respect to harvesting activities and then identify governance needs that could support sustainability. Results of the study are organised by three major risk themes: (1) Marine ecosystem contamination and degradation; (2) Disruption to harvesters’ travel and safety; and (3) Interference and disturbance of wildlife. All of these risks negatively impact harvesting activities in Inuit Nunangat. Considering the region is expected to be ice-free in summer by the end of the twenty-first century and that subsistence harvesting is crucial to the well-being of Inuit and northern communities, it is vital that research on this topic be conducted and then considered within ongoing Arctic governance and co-governance efforts. [ABSTRACT FROM AUTHOR]

This paper describes a vibration energy harvester based on an origami mechanism through piezoelectric energy conversion. The device is capable of broadband energy harvesting from low frequency ambient vibrations. This design utilizes bistability inherent in the waterbomb base origami structure to increase the bandwidth of its frequency response. The folding along the crease pattern of the origami mechanism can facilitate large bending deformations of piezoelectric films to generate high electric power output. The compact size and light weight of the origami mechanism render it convenient for integration into various hosts subjected to vibrations. Performance of the origami mechanism is investigated under external excitations with various vibration magnitudes and acceleration levels. This work demonstrates a scheme of broadband vibration energy harvesting by integration of an origami structure with piezoelectric materials. A high fractional bandwidth of 40% is attained under a sinusoidal excitation with a peak acceleration of 0.1 g. [ABSTRACT FROM AUTHOR]

The number of coral reefs around the world is slowly declining due to environmental and anthropogenic reason, and Pterois volitans also put extra stress on coral reefs by decreasing the number of herbivorous fishes (parrotfish). Moreover, uncontrolled growth of algae interrupts the growth of corals since corals and algae grow together on algal turf. Here Parrotfish also play an important role in the enhancement of corals by grazing. In this paper, parrotfish and P-volitans are taken as prey and predator, respectively, and the fear effect on the dynamics of the system is investigated. The effect of prey refuge is also shown. Constant harvesting policy for both fishes is included. Stable coexistence region for two parameter spaces: Hopf bifurcation and saddle-node bifurcation, is shown and formulated for the system. Numerical simulations are illustrated to verify the authenticity of the analytical calculations. [ABSTRACT FROM AUTHOR]

This paper introduces the use of rhombus shaped dipole nanoantenna coupled to geometric diode in energy harvesting at 19.4 THz. An arc-shaped geometric diode is placed in the gap between the dipole arms. The diode I–V characteristics are investigated using the Monte Carlo simulation. Two approaches for enhancing the received voltage of nanoantenna energy harvesting at 19.4 THz are investigated. In the first approach, a terahertz transparent transmitarray is used to focus the electromagnetic waves on the surface of the nanoantenna coupled to the geometric diode. The received voltage is increased from 16.5 μV for single nanoantenna to 97.6 μV for the transmitarray coupled to the nanoantenna. In the second approach, Yagi nanoantenna arrangements are used to enhance the directivity of the single element and is coupled to the transmitarray. [ABSTRACT FROM AUTHOR]

Many of the world’s forests are being destroyed at a rapid rate. This article analyzes the decisions of landowners in Maine, where forests have been heavily harvested and much land has been converted to non-forest use. Data on these landowners and their land were obtained from primary and secondary sources, satellite change detection analysis, and structured interviews. We found that there are several different landowner groups making different harvesting decisions in response to different incentives. In northern Maine, deforestation occurred at a rapid rate in the 1970s–1990s due to the activities of paper companies, which were harvesting heavily in the aftermath of a spruce budworm epidemic and which were doing liquidation harvesting preparatory to leaving Maine. In the southern area of the state, deforestation is due primarily to small landowners converting land for development and contractors doing “cut and run” forestry. The Maine case shows that even in a small area, there can be multiple causes for deforestation. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.1007/s10343-020-00528-0 [ABSTRACT FROM AUTHOR]

Over the last three decades most of the world's fisheries have been subject to management programs that have tried to limit the use of key fishing inputs. Inevitably, these restrictions have proven ineffective at preventing rent dissipation and stock depletion. More noteworthy is that fishers have subverted the intentions of these restrictions by adjusting the primary harvesting technology. This has led to an inefficient industrial structure characterized by capital stuffing on the part of each vessel, excess employment, an inefficient mix of vessels in the fleet, and too many vessels altogether. A promising means of encouraging more efficient primary harvesting is the individual transferable vessel quota that allocates a given catch to each vessel, thereby giving an incentive to catch the quota at least cost. This paper examines efficiency gains and potential industry restructuring from the introduction of an ITVQ into a fishery that was previously subject to input restrictions. Using data from the British Columbia salmon fishery, this paper estimates restricted cost functions for each of four different vessel types and simulates the operations of a market for ITVQs. The demand for quota comes from individual vessels and is found by differentiating the cost function with respect to the shadow price of quota. The market for quota is in equilibrium when the total demand for quota is equal to the fixed supply of quota set by the government. This implicitly defines the equilibrium quota rental price. Results show that the ITVQ could generate unit rental prices for quota between 31 and 93 cents per pound (18–53% of the average landed price). Using this simulated price, each vessel's cost-minimizing strategy is defined and both low cost vessels (those that will buy quota) and high cost vessels (those that will sell quota and exit the fishery) are identified. Quota trades between the two groups result in efficiency gains. These include reduced capital stuffing, exit of less efficient vessel types, attainment of economies of scale, and an efficient composition of vessel types in the fleet. In aggregate these gains lead to an estimate of annual resource rent that is approximately equal to one third of the value of the catch. [ABSTRACT FROM AUTHOR]

Purpose: Digital 3D exoscopes have been recently introduced as an alternative to a surgical microscope in microneurosurgery. We designed a laboratory training program to facilitate and measure the transition from microscope to exoscope. Our aim was to observe the effect of a one-year active training on microsurgical skills with the exoscope by repeating a standardized test task at several time points during the training program. Methods: Two board-certified neurosurgeons with no previous exoscope experience performed the same test tasks in February, July, and November during a 12-month period. In between the test tasks, both participants worked with the exoscope in the laboratory and assisted during clinical surgeries on daily basis. Each of the test segments consisted of repeating the same task 10 times during one week. Altogether, 60 test tasks were performed, 30 each. The test task consisted of dissecting and harvesting the ulnar and radial arteries of the second segment of a chicken wing using an exoscope (Aesculap AEOS). Each dissection was recorded on video and analyzed by two independent evaluators. We measured the time required to complete the task as well as several metrics for evaluating the manual skills of the dissection and handling of the exoscope system. Result: There was a clear reduction in dissection time between the first and the last session, mean 34 min (SD 5.96) vs. 26 min (SD 8.69), respectively. At the end of the training, both neurosurgeons used the exoscope more efficiently utilizing more available options of the device. There was correlation between the dissection time and several of the factors we used for evaluating the work flow: staying in focus, zoom control, reduction of unnecessary movements or repetitive manual motions, manipulation technique of the vessel under dissection, handling of the instruments, and using them for multiple dissection purposes (stretching, cutting, and splitting). Conclusion: Continuous, dedicated long-term training program is effective for microsurgical skill development when switching from a microscope to an exoscope. With practice, the micromotor movements become more efficient and the use of microinstruments more versatile. [ABSTRACT FROM AUTHOR]

The present work describes the hybridization of two different energy harvesters works simultaneously in a single package. By applying simultaneous mechanical force, two components such as triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) independently produce power. The hybrid device was made with a polymeric cylinder composed of Kapton in the inner wall; a copper coil wound outside the cylinder and neodymium magnet and small bits of paper housed inside it. The paper flakes having the dimension of 5 mm × 5 mm, which are triboelectric positive slides over the negative triboelectric layer Kapton. The potential difference between the two different triboelectric material leads to the generation of electric power. The triboelectric component generates the maximum output with the voltage of ≈ 20 V and the current of 300 nA. The magnet inside the cylinder moves simultaneously along with the paper made the production of electric flux in the coil. The alternating magnetic flux induces the current in the outer coil as per the Lenz's law. The maximum output generated from the EMG component with the obtained voltage of 2 V and the maximum current of 10 mA. Further, to analyze the actual working behavior of the device, commercial capacitor charging behavior was analyzed. The TENG component runs the consistent charging behavior, whereas the EMG component offers a rapid charging behavior, under hybrid mode both the merits can be utilized. The device has had placed in a backpack, and the biomechanical energy from human motions such as walking, running and jumping had been demonstrated. This study confirms that the proposed hybrid generator is capable of powering small electronic devices such as global positioning system (GPS), flashlights and potentially be able to use as an active MEMS/NEMS-based self-powered sensor. [ABSTRACT FROM AUTHOR]

As a generalization, harvested timber is extracted from forests either as trees or stems by skidders or as logs by forwarders. Coupled with harvesters, forwarders team up to form cut-to-length (CTL) systems that are often perceived to be more modern than full-tree (FT) and tree-length (TL) systems, based on feller bunchers and skidders. As a result, CTL machinery has been extensively studied in Europe, while little information is available on FT and TL machinery and especially skidders. Using all available documentation, and relying on national experts, this paper reports on a survey of skidders used for timber extraction in Europe. The survey identified a total of 8370 skidders, whereby the authors accept this to be a lower limit with potentially many other units not identified through the survey. Also, while the focus of the survey was purpose-built skidders, many modified farm tractors are also used to extract tree-length material. Of the 8370 skidders, 5500 were found in the Central European region with Germany and France dominating the market. The survey also indicated an overall low level of replacement, with fewer than 5% being from new sales annually. Although CTL systems are a dominant harvesting option, this survey has shown that skidders continue to be a common and viable extraction method. Given their high level of extraction efficiency that is often restricted by a limit of clear-fell operations, further large-scale damaging storm events in Europe may offer a clear opportunity for their expansion. [ABSTRACT FROM AUTHOR]

A diffusive phytoplankton–zooplankton model with nonlinear harvesting is considered in this paper. Firstly, using the harvesting as the parameter, we get the existence and stability of the positive steady state, and also investigate the existence of spatially homogeneous and inhomogeneous periodic solutions. Then, by applying the normal form theory and center manifold theorem, we give the stability and direction of Hopf bifurcation from the positive steady state. In addition, we also prove the existence of the Bogdanov–Takens bifurcation. These results reveal that the harvesting and diffusion really affect the spatiotemporal complexity of the system. Finally, numerical simulations are also given to support our theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper deals with the forest owner's attitude towards risk and the harvesting decision in several ways. First, we propose to characterize and quantify the forest owner's attitude towards risk. Second, we analyze the determinants of the forest owner's risk attitude. Finally, we determine the impact of the forest owner's risk attitude on the harvesting decision. The French forest owner's risk attitude is tackled by implementing a questionnaire, including a context-free measure borrowed from experimental economics. The determinants of the forest owner's risk attitude and harvesting decision are estimated through a recursive bivariate ordered probit model. We show that French forest owners are characterized by a relative risk aversion coefficient close to 1 with a DARA assumption. In addition, we find that the forest owner's risk aversion is influenced positively and significantly by the level of risk exposure, the geographical location of the forest and the fact to be a forester, and negatively by the income. Finally, we obtain that the forest owner's risk aversion has a positive and significant impact on the harvesting decision. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the optimal harvesting strategies of a stochastic competitive Lotka–Volterra model with S-type distributed time delays and Lévy jumps by using ergodic method. Firstly, the sufficient conditions for extinction and stable in the time average of each species are established under some suitable assumptions. Secondly, under a technical assumption, the stability in distribution of this model is proved. Then the sufficient and necessary criteria for the existence of optimal harvesting policy are established under the condition that all species are persistent. Moreover, the explicit expression of the optimal harvesting effort and the maximum of sustainable yield are given. [ABSTRACT FROM AUTHOR]

This paper outlines a model for the domestication of Panicum miliaceum (broomcorn millet) in Northern China. Data from 43 archaeological sites indicate a continuous increase in average grain size between 6000 and 3300 bc. After this date there is a divergence, with grain size continuing to increase in some populations, while others show no further size increase. The initial increase in grain size is attributed to selection during domestication, while later divergence after 3300 bc is interpreted as resulting from post-domestication selection. Measurements of grains from two archaeological populations of P. ruderale, showed grains were longer in length by 3300 bc than the earliest grains of P. miliaceum. This suggests this sub-species includes many feral, weedy and/or introgressed forms of P. miliaceum and therefore is probably not entirely representative of the true wild ancestor. It is argued that changes from shattering to non-shattering are contemporary with increasing grain size and the commencement of cultivation. The window of P. miliaceum domestication is therefore likely to lie between 7000 and 3300 bc. However, it is probable that a lengthy period of millet harvesting and small-scale management preceded its domestication. [ABSTRACT FROM AUTHOR]