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Enhancing crop water use efficiency (WUE) is a key target trait for climatic resilience and expanding cultivation on marginal lands. Engineering lower stomatal density to reduce stomatal conductance (g s) has improved WUE in multiple C3 crop species. However, reducing g s in C3 species often reduces photosynthetic carbon gain. A different response is expected in C4 plants because they possess specialized anatomy and biochemistry which concentrates CO2 at the site of fixation. This modifies the relationship of photosynthesis (A N) with intracellular CO2 concentration (c i), such that photosynthesis is CO2 saturated and reductions in g s are unlikely to limit A N. To test this hypothesis, genetic strategies were investigated to reduce stomatal density in the C4 crop sorghum. Constitutive expression of a synthetic epidermal patterning factor (EPF) transgenic allele in sorghum led to reduced stomatal densities, reduced g s, reduced plant water use, and avoidance of stress during a period of water deprivation. In addition, moderate reduction in stomatal density did not increase stomatal limitation to A N. However, these positive outcomes were associated with negative pleiotropic effects on reproductive development and photosynthetic capacity. Avoiding pleiotropy by targeting expression of the transgene to specific tissues could provide a pathway to improved agronomic outcomes. [ABSTRACT FROM AUTHOR]

Bearing component damage contributes significantly to rotating machinery failures. It is vital for the rotor-bearing system to be in good condition to ensure the proper functioning of the machine. Over recent decades, extensive research has been devoted to the condition monitoring of rotational machinery, with a particular focus on bearing health. This paper provides a comprehensive literature review of recent advancements in intelligent condition monitoring technologies for rolling element bearings. Fundamental monitoring strategies are introduced, covering various sensing, signal processing, and feature extraction techniques for detecting defects in rolling element bearings. While vibration-based monitoring remains prevalent, alternative sensor types are also explored, offering complementary diagnostic capabilities or detecting different defect types compared to accelerometers alone. Signal processing and feature extraction techniques, including time domain, frequency domain, and time–frequency domain analysis, are discussed for their ability to provide diverse perspectives for signal representation, revealing unique insights relevant to condition monitoring. Special attention is given to information fusion methodologies and the application of intelligent algorithms. Multisensor systems, whether homogeneous or heterogeneous, integrated with information fusion techniques hold promise in enhancing accuracy and reliability by overcoming limitations associated with single-sensor monitoring. Furthermore, the adoption of AI techniques, such as machine learning, metaheuristic optimisation, and deep-learning methods, has led to significant advancements in condition monitoring, yielding successful outcomes with improved accuracy and robustness in various studies. Finally, avenues for further advancements to improve monitoring accuracy and reliability are identified, offering insights into future research directions. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2005.11.016 Byline: Gregory Levitin (a), Min Xie (b), Tieling Zhang (b) Keywords: Performance; Fault-tolerant software; Multiprocessor system; Universal generating function Abstract: The paper considers performance and reliability of fault-tolerant software running on a hardware system that consists of multiple processing units. The software consists of functionally equivalent but independently developed versions that start execution simultaneously. The computational complexity and reliability of different versions are different. The system completes the task execution when the outputs of a pre-specified number of versions coincide. The processing units are characterized by different availability and processing speed. It is assumed that they are able to share the computational burden perfectly and that execution of each version can be fully parallelized. The algorithm based on the universal generating function technique is used for determining the distribution of system task execution time. This algorithm allows analysts to evaluate complex hardware-software reliability and performance indices such as expected task execution time and probability that the task is completed within a given time. Illustrative examples are also presented. Author Affiliation: (a) Reliability Department, Planning, Development and Technology Division, Israel Electric Corporation Ltd., P.O. Box 10, Haifa 31000, Israel (b) Department of Industrial and Systems Engineering, National University of Singapore, Singapore 117576, Singapore Article History: Received 31 December 2004; Accepted 10 November 2005

System reliability is discussed in systems that endure environmental shocks where components can fail simultaneously because of cumulative shock damage. A methodology for reliability and availability analysis is proposed, for repairable systems in which failure and repair rates vary with time.

Caregivers of people with dementia (PwD) frequently experience poor physical, mental and social health. Over the past decade, several guidelines have offered recommendations on supporting caregivers to improve their health outcomes. This systematic review aimed to assess the quality and evidence base of guidelines on supporting caregivers of PwD and review the content of their recommendations on caregiver support to facilitate the adoption and implementation of a specific guideline among policymakers and practitioners. A systematic search for guidelines on supporting caregivers of PwD was performed using journal databases, websites of guideline development organisations and professional dementia‐related societies from inception to 30 June 2020. Four independent reviewers performed the quality assessment of the included guidelines using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. A thematic synthesis was used to analyse the content of recommendations on caregiver support extracted from the included guidelines by two independent reviewers. The strength of recommendations and level of evidence were reclassified and analysed. Literature searches identified nine guidelines. Their quality was variable. The applicability domain on AGREE II yielded the lowest median score (62.2%; range: 18.6%–86.6%), suggesting that some guidelines lacked applicability in certain fields, leaving them open to interpretation. Most evidence underlying the extracted recommendations was rated as Levels 3 (51.3%) and 4 (31.1%). High‐quality evidence is required to fortify these recommendations. The nine guidelines covered six themes—assessment, education, skill training, information provision, psychosocial support and general support policies—which can guide future policies and interventions of caregiver support. The recommendations extracted were consistent across guidelines, but each guideline failed to cover all six themes. Thus, more applicable and comprehensive guidelines that fully address all themes of support for caregivers of PwD are needed. [ABSTRACT FROM AUTHOR]