Life Cycle Strategies Research Articles

Legacy effects of rhizodeposits on soil microbiomes: A perspective

Plant legacy effects observed in plant-soil feedback experiments have largely been attributed to the root or litter material of the previous plant. The legacy effects of rhizodeposits are defined as changes in the soil microbiome that remain after a plant has died or been removed from the soil and caused by the release of substances of various compositions by living plants (rhizodeposits). Rhizodeposit-mediated legacy effects have been largely ignored mainly due to the high spatial and temporal variability of rhizodeposits and difficulties quantifying and tracking them in the rhizosphere. In this perspective article, we discuss what is known about the legacy effects of rhizodeposits and provide ideas for future experiments to improve understanding of this phenomenon. Only a few studies separate rhizodeposit-mediated plant legacy effects from legacy effects of root decomposition. Results from these experiments indicate that rhizodeposit-mediated legacy effects on soil microbial communities may persist for several months to several years, especially if the same crop is cultivated persistently for several years in a ‘conditioning’ phase. Rhizodeposit-mediated legacy effects on fungal communities usually last longer than those on bacterial communities due to fungal life-cycle strategies (spore formation) and slower reproduction rates, compared to bacterial communities. We highlight the need for further experimentation to investigate the influence that the length of a conditioning phase has on the persistence of the legacy effect, differentiate the effect of root exudates from the effects of sloughed root cells, separate the influence of simple sugars from that of high molecular-weight exudates and plant derived compounds with antimicrobial properties, and explore whether plant species diversity influences the nature of the legacy. To address these questions, we propose the use of contemporary tools such as stable isotope probing, plant genetics, and reverse microdialysis. We think that harnessing rhizodeposit-mediated plant legacy effects could be a promising approach to improve sustainable crop production by creating disease-suppressive soils and simulating plant growth-promoting micro-organisms within soil systems.

Developing Bontomarannu as a Tourism Village at Selayar Islands Regency, South Sulawesi

Purpose: The purpose of this study is to identify the development of tourist destinations in Bontomarannu Village, Selayar Islands Regency, South Sulawesi through the study of the 4A tourism components namely attraction, accessibility, amenity and ancillary tourism area life cycle (TALC) and growth strategy matrix for tourism villages. Research methods: This research uses a qualitative approach using interview techniques, participatory observation, documentation and focus group discussion. Data analysis techniques include data reduction, data presentation, and drawing conclusions. All data collected was analyzed using Nvivo 12 plus software. Findings: The potential of Bontomarannu Tourism Village is in two stages, namely the exploration stage and the involvement stage because the conditions of the potential of each tourist attraction are different. Bontomarannu Village has tourist destinations such as natural tourism, historical tourism and religious tourism. The village as a destination makes the local community and BUMDES (Village-Owned Enterprises) synergize and work hard to develop their village into a tourist village that is different from other villages. Implication: Development efforts are needed so that Bontomarannu Tourism Village can continue to grow and its tourist attractions continue to increase with aspects focused on development consisting of attraction, accessibility, amenities and ancillary.

Intergenerational risk sharing in a defined contribution pension system: analysis with Bayesian optimization

AbstractWe study a fully funded, collective defined contribution (DC) pension system with multiple overlapping generations. We investigate whether the welfare of participants can be improved by intergenerational risk sharing (IRS) implemented with a realistic investment strategy (e.g., no borrowing) and without an outside entity (e.g., shareholders) that helps finance the pension fund. To implement IRS, the pension system uses an automatic adjustment rule for the indexation of individual accounts, which adapts to the notional funding ratio of the pension system. The pension system has two parameters that determine the investment strategy and the strength of the adjustment rule, which are optimized by expected utility maximization using Bayesian optimization. The volatility of the retirement benefits and that of the funding ratio are analyzed, and it is shown that the trade-off between them can be controlled by the optimal adjustment parameter to attain IRS. Compared with the optimal individual DC benchmark using the life cycle strategy, the studied pension system with IRS is shown to improve the welfare of risk-averse participants, when the financial market is volatile.

An experimental animal model of yellowfin seabream (Acanthopagrus latus) for Amyloodinium ocellatum infection

Amyloodinium ocellatum is a worldwide distributed protozoan that infects almost all marine fish species, causing fatal amyloodiniosis. However, highly effective antiparasitic agents for controlling amyloodiniosis are lacking. This study was conducted to establish a laboratory model of A. ocellatum infection, facilitating the development of alternative treatment options and immunostimulants for A. ocellatum using yellowfin seabream (Acanthopagrus latus) as the experimental host. The life cycle and preservation strategies of A. ocellatum, the stability of dinospore infection in A. latus, and the tolerance of A. latus to A. ocellatum infection were observed and evaluated. Under suitable conditions (temperature: 27 ± 1 °C; salinity: 30 ± 1‰), A. ocellatum completes its life cycle on A. latus in 4–5 d and peak trophont detachment from A. latus occurs at 44–52 h post-infection. The peak period when tomonts release dinospores occurs 51–60 h after incubation at 28 °C. Dinospores have high vitality and infectivity within 6 h of release from tomonts. The infection model developed in this study is stable, with a 39.85–44.68% dinospore infection rate. Additionally, gills were the main A. ocellatum infection site, accounting for 70.49–72.68% of the total trophonts in infected A. latus. The maximal tolerance dose (MTD) and lethal concentration 50 (LC50) of A. ocellatum to A. latus were 14,686 and 28,901 dinospores per fish, respectively. Tomonts can be preserved for at least 3 months at 12 °C. This study established an A. ocellatum infection model under laboratory conditions, which is potentially helpful in exploring alternative treatments and investigating the pathogenic mechanisms of amyloodiniosis.

A REVIEW ON THE INVASIVE VEGETABLE LEAF MINER (Diptera: Agromyzidae): LIFE CYCLE, DAMAGE SYMPTOMS, AND MANAGEMENT

The leaf miner is a juvenile stage of insects that dwell within the leaves of vegetables and feed on their tissues. It belongs to the family of dipteran flies and has a polyphagous feeding habit, meaning it can consume a wide range of plants. This comprehensive review paper provides an in-depth analysis of the invasive vegetable leaf miner, covering topics such as its life cycle, damage symptoms, and management strategies. The vegetable leaf miner is an invasive pest that causes significant damage to vegetable crops, particularly solanaceous crops. The paper explores the biology and ecology of the vegetable leaf miner, including its life cycle and host range. It also describes the damaging symptoms caused by the pest, which include the formation of distinctive tube patterns on the leaves. The paper further investigates the various management strategies that have been developed to control the spread of the vegetable leaf miner, including chemical, cultural, and biological control measures. The aim of this paper is to provide a comprehensive overview of the invasive vegetable leaf miner and to highlight the most effective management strategies for controlling its spread and minimizing its impact on crop yields.

EV-A71 Infections: Life Cycle and Prevention Strategies

Hand, Foot, and Mouth disease (HFMD) is a highly contagious disease caused by enteroviruses, which is common in Asia-Pacific countries, including China, Hong Kong, Korea, Malaysia, Singapore, Thailand, and Vietnam. Children are more susceptible to infection, especially newborns and children under-5-year-old. HFMD may cause severe symptoms like encephalitis, meningitis, myocarditis, and acute pulmonary edema which can lead to death if no early detection or prompt treating is carried out. Various professional researches indicated the main causes of HFMD were enteroviruses in the Picornaviridae family, particularly Coxsackievirus A16 (CVA16) and Enterovirus 71 (EV71). Both factors cause the same beginning symptoms, but while CVA16’s are mild and can be self-recuperated after 10-14 days, EV71’s are more dangerous and can lead to neurological, cardiovascular, and respiratory complications, causing death or permanent brain damages.
 Preventing EV71 infection is extremely necessary as it not only decreases severe HFMD but also interferes with the virus speciation through homologous recombination to reduce the complexity of epidemic situation in the world. Therefore, synthesizing information about the virus life cycle and prevention strategies against EV71 is crucial and essential to provide an overview about the potential methods for vaccines and medicines development or food supplement manufactures which contributes to preventing EV71 infection.

Novel insights into maize (Zea mays) development and organogenesis for agricultural optimization

In maize, intrinsic hormone activities and sap fluxes facilitate organogenesis patterning and plant holistic development; these hormone movements should be a primary focus of developmental biology and agricultural optimization strategies. Maize (Zea mays) is an important crop plant with distinctive life history characteristics and structural features. Genetic studies have extended our knowledge of maize developmental processes, genetics, and molecular ecophysiology. In this review, the classical life cycle and life history strategies of maize are analyzed to identify spatiotemporal organogenesis properties and develop a definitive understanding of maize development. The actions of genes and hormones involved in maize organogenesis and sex determination, along with potential molecular mechanisms, are investigated, with findings suggesting central roles of auxin and cytokinins in regulating maize holistic development. Furthermore, investigation of morphological and structural characteristics of maize, particularly node ubiquity and the alternate attachment pattern of lateral organs, yields a novel regulatory model suggesting that maize organ initiation and subsequent development are derived from the stimulation and interaction of auxin and cytokinin fluxes. Propositions that hormone activities and sap flow pathways control organogenesis are thoroughly explored, and initiation and development processes of distinctive maize organs are discussed. Analysis of physiological factors driving hormone and sap movement implicates cues of whole-plant activity for hormone and sap fluxes to stimulate maize inflorescence initiation and organ identity determination. The physiological origins and biogenetic mechanisms underlying maize floral sex determination occurring at the tassel and ear spikelet are thoroughly investigated. The comprehensive outline of maize development and morphogenetic physiology developed in this review will enable farmers to optimize field management and will provide a reference for de novo crop domestication and germplasm improvement using genome editing biotechnologies, promoting agricultural optimization.

Optimisation of Bioethanol Production in a Potato Processing Industry

Nowadays, there is a requirement for industries to eliminate carbon from their energy mix and substitute it with greener options. This calls for investment in efforts to facilitate the scaling up of technical advancements. Because of the huge amount of waste, a life cycle strategy has been used by industries, especially the food industry, to lessen the environmental impact of their products. One of the sectors that burdens the environment with a significant amount of waste is the potato processing industrial sector. The current study focuses on the valorisation of all the potato processing waste streams (potato peels, potato tubers and slices, starch and low-quality chips) towards bioethanol production at a pilot level. After their physico-chemical characterisations, several experimental trials were performed in order to determine the optimum pretreatment and hydrolysis conditions for each waste stream. Acid hydrolysis, alkaline hydrolysis and hydrothermal pretreatment were examined when no pretreatment resulted in low ethanol yields (below 60%). The optimum results that were obtained were applied in a pilot plant of 200L to examine the upscaling factor. It was verified that upscaling by 1000 times generates comparable and, in some cases, greater results. From the integration of the results and the mass balances of a typical potato processing company, a full-scale implementation plan was also set up, where it was calculated that around 2 m3 bioethanol per week could be produced.

Pengembangan Aplikasi E-learning dengan Metode Rapid Application Development

The development of the E-learning application is part of the solution for convenience in carrying out teaching and learning activities, the process of receiving and sending a digital document in the form of learning videos and ebooks is the most important part so that information can be accessed quickly and easily. Special methods are needed to build e-learning applications more quickly and according to needs. Requirements Planning plays a very important role in the software development process, project management in software development and one of the processes is to estimate that the software produced is according to a predetermined schedule and cost. The Rapid Application Development Method is a life cycle strategy aimed at To provide development that is much faster and get results with better quality, UML (Unified Modeling Language) is a language that has become a decent standard in designing, visualizing and documenting software.

Anatomy and histological evaluation of the reproductive system of marine calanoid copepod Centropages furcatus from a mass culture perspective

Marine finfish culture is a priority area for future human food security. Although many marine finfish species have been domesticated and successful breeding and spawning in captive conditions are achieved, the larval rearing from hatchling to fingerling stage to the desired level is yet to be achieved. One of the essential impediment factors in this process is the availability of suitable live feed for the finfish larvae. The traditional live feeds (Artemia nauplii and rotifers) must be more adequate in size spectrum and nutritive value to many marine finfish larvae. In nature, copepod nauplii, copepodite stages, and adults constitute the preferred food of marine finfish larvae. Copepod size spectrum, nutritive value and swimming movements make them ideal live prey items for fish larvae. Nevertheless, the high-density culture of copepods is challenging due to their sexual reproduction and high species-specific variability. Further, adequate knowledge of the candidate species' food and feeding habits, reproductive biology, and life cycle strategies should exist. With this objective present study describes the female and male reproductive system, oogenesis and spermatogenesis, egg production, and reproductive potential of a candidate calanoid copepod species, Centropages furcatus. This basic information will help develop mass culture protocol for this species.

Emergence timing and voltinism of phantom midges, Chaoborus spp., in the UK

Abstract. Phantom midges, Chaoborus spp. (Diptera: Chaoboridae), are an important taxon in environmental risk assessment of plant protection products due to the sensitivity of their larvae to insecticides. To aid modelling of population responses to xenobiotic exposure, information on emergence timing and voltinism is needed, but definitive evidence to support these parameters is lacking in the literature. We investigated emergence timing of overwintering Chaoborus larvae and the number of life cycles occurring per year in two separate, mesh-enclosed outdoor microcosm experiments in the spring and summer of 2017. Emergence from overwintering larvae of a population of predominantly C. obscuripes (99.68 %) commenced on 13 April and peaked on 2 May. The majority of emergence was completed by 3 June. Emergence success ranged from 51.4 % to 66.2 %, indicating that for overwintered C. obscuripes larvae, adults emerged contemporaneously in spring, rather than sporadically over the course of spring and summer. A population of C. crystallinus larvae produced up to four discrete generations over the spring and summer months (i.e. were confirmed to be multivoltine), with life cycle durations (egg-to-egg) ranging from 14 to 56 d. The differences in life cycle strategy observed in this study have implications for assessment of the capacity of populations of Chaoborus spp. to recover if there are localised impacts due to insecticide exposure or other stressors.

Effect of Cellulose Acetate (CA-398-10 NF/ EP) on Osmotically Controlled Drug Delivery System of Amitriptyline

Background: Amitriptyline hydrochloride is a Tricyclic Antidepressant (TCA) belonging to BCS class I exhibiting only 30-60% bioavailability and often coupled with poor patient compliance. The primary objective was to develop a formulation with commercial viability and to reduce dosing frequency in order to promote adherence of depressed patients to the treatment regime. The study also focused on reducing the dose of amitriptyline by controlling the release using osmotic technology; thereby reducing the side effects of amitriptyline. Methods: Controlled Porosity Osmotic Pump (CPOP) systems eliminate the need for expensive drilling processes and in turn are apt for industrial manufacturing systems where as other osmotic systems have practical limitations. Wet granulation technique was used for the formulation of CPOP tablets of amitriptyline as burst release was observed in directly compressed tablets. Screening of polymers, osmogen and weight gain were performed. Results: F6-D3 (3 % Di-butyl phthalate) with lactose as osmogen and HPMC K 35 M as polymer was optimized. The drug release from the optimized formulation was found to be independent of the effect of agitational intensity and pH. To confirm the osmotic release mechanism, the osmotic pressure of the dissolution medium was increased. The drug release decreased markedly due to an increase in osmotic pressure. Conclusion: Accelerated Stability studies were carried out in ICH certified stability chambers as per the specifications and were found to be stable. It was evident that osmotic pressure generated within the CPOP tablets along with the controlled formation of pores using Cellulose Acetate (CA-398-10 EP/ NP) was able to control the release of amitriptyline hydrochloride for 24 hours. Thus, the Oral Osmotic Drug Delivery system is a promising technology for product life-cycle strategies.

Life Cycle Strategies of the Centric Diatoms in a Shallow Embayment Revealed by the Plankton Emergence Trap/Chamber (PET Chamber) Experiments

In situ emergence of the centric diatoms from the surface sediment, along with the occurrence of the vegetative cells in the water column, were monitored monthly in a shallow embayment, Ago Bay, of central Japan, where light penetrated to the seafloor. The in situ emergence flux (cells m-2 day-1) was measured by experiments using a ‘plankton emergence trap/chamber (PET chamber)’. During the study period from July 2006 to May 2008, germinating and rejuvenating cells of centric diatoms were successfully collected by the PET chamber. Furthermore, vegetative cells forming long-chain colonies, including the species which have not been known to form resting stage cells, were also found, indicating that these cells already inhabited the surface sediment prior to the start of the PET chamber experiments. The vegetative cells could be cells that grew after germination/rejuvenation and/or cells deposited from the upper layer in the water column. When comparing emergence flux in the PET chamber and the integrated abundance of the vegetative cells in the water column for the diatoms frequently observed, significant positive relationships were found for some diatom taxa. However, even for these taxa that showed a clear relationship, the magnitude of the vegetative population in the water column did not necessarily correlate with that of the emergence flux. These observations indicate that the magnitude of the vegetative population was not regulated directly by the emergence flux. The magnitude of the vegetative population could be dependent on the vegetative growth itself. This implies that the presence of vegetative cells in the water column is important at the time when environmental conditions become suitable for vegetative growth. In this context, the presence of various types of cells, such as germinating, rejuvenating, and vegetative cells, in the sediment is essential as seeds waiting for recruitment into the water column. Consequently, the seafloor in Ago Bay may act as a ‘refuge and nursery’ for centric diatoms. Based on the above, we demonstrated various patterns of life cycle strategies of the diatoms in a shallow coastal water/embayment.

Life cycle stage practices and strategies for circular economy: assessment in construction and demolition industry of an emerging economy

The strategic implementation of circular economy (CE) practices in the construction and demolition (C&D) industry is critical for achieving environmental sustainability goals. Understanding CE practices based on reduce, reuse, recycle, recover, remanufacture, and redesign (6R) principles from the perspective of the whole life cycle can promote the implementation of CE practices in the C&D industry. However, studies that shed light on this subject especially in emerging economies are generally lacking. This study contributes to filling this gap by using a three-phase methodology consisting of a literature review and a hybrid best–worst method and grey relational analysis to give insights into practices and strategies to prioritize CE practice implementation. Specifically, the paper focuses on identifying CE practices based on 6R principles, the significance of the identified CE practices, and understanding how to prioritize the implementation of the significant CE practices. The study’s findings established that implementing CE practices based on reduce and recover principles at the design stage contributes significantly to environmental sustainability. Additionally, the study highlights the relevance of both bottom-up and top-down approaches in the implementation of CE practices.

Expert Consensus on Obesity Prevention and Treatment in China

Obesity and related chronic diseases have become major public health problems in China and in the world. While a series of prevention and control policies and action plans have been implemented in China, obesity and related chronic diseases have not been effectively controlled yet. The Obesity Prevention and Control Section of the Chinese Nutrition Society facilitated the cooperation of 34 interdisciplinary leading experts in drafting this consensus based on the latest relevant guidelines and research results in China and from overseas. The consensus report aims to help guide the prevention and treatment of obesity in China, promote the participation of the whole society and contribute to 'Healthy China' national goals. This report includes seven chapters. It outlines the prevalence and main contributing factors of obesity, challenges, obesity screening and diagnosis, treatment, prevention and control during the whole life cycle, comprehensive prevention and control strategies involving the whole society, and recommendations for future work in China. This report will help promote obesity prevention and weight management efforts in China to be more scientific and effective.

Alternating nuclear DNA content in chrysophytes provides evidence of their isomorphic haploid-diploid life cycle

Across eukaryotic organisms there is a great diversity of life cycles. This particularly applies to unicellular eukaryotes (protists), where the life cycles are still largely unexplored, although this knowledge is key to understanding their biology.To detect the often inconspicuous transitions among life cycle stages, we focused at shifts in ploidy levels within strains of unicellular chrysophyte alga. Representatives of three genera (Chrysosphaerella, Ochromonas, and Synura) were analysed for nuclear DNA contents using a propidium iodide flow cytometry. Selected strains exhibiting ploidy level variation were also surveyed for DNA base composition (GC content) and cell size. Additionally, we tracked ploidy level changes in seven strains under long-term cultivation.An alternation of two ploidy levels was revealed in the life cycle of chrysophytes with both life cycle stages capable of mitotic growth and long-term survival in cultivation. With the exception of a small increase in cell size with higher ploidy, both life cycle stages shared the same phenotype and also had highly similar genomic GC content. Further, we detected three ploidy levels in two Synura species (S. glabra, S. heteropora), where the highest ploidy (putatively 4x) most likely resulted from a polyploidization event.Consequently, chrysophytes have a haploid-diploid life cycle with isomorphic life cycle stages. As far as we know, this is the first report of such life cycle strategy in unicellular algae. Life cycle stages and life stage transitions seem to be synchronized among all cells coexisting within a culture, possibly due to chemical signals. Particular life stages may be more successful under certain environmental conditions, for our studied strains the diploid stage prevailed in cultivation.

Sparse enhancement based on the total variational denoising for fault feature extraction of rolling element bearings

As one of the essential parts of the mechanical transmission system, rolling bearing is vital to ensure the safe operation of mechanical equipment. The rolling bearing goes through four stages from its installation to the end of its life: normal operation, early weak failure, serious failure, and failure. If faults can be found in the early failure stage of the whole life cycle and maintenance strategies can be adopted in time, the safe and trouble-free operation of the equipment can be guaranteed. However, the fault features are not apparent in the early failure stage of the bearing’s full life cycle. Moreover, being completely submerged in strong background noise can easily occur, making early fault diagnosis challenging. This study presents a new sparse enhancement model based on kurtosis-wavelet total variation denoising (Kurt-WATV) for early fault feature extraction. Firstly, a sparse optimization model is constructed to extract the early fault feature, and the original signal is decomposed by the over-complete rational discrete wavelet transform (ORDWT). Then a fast iterative algorithm is deduced to solve the established sparse optimization model, and the optimal wavelet subband is selected by Kurt-WATV, which is reconstructed to the fault signal. Finally, the bearing test data from bearing’s full-life cycle are adopted to illustrate the effectiveness and robustness of the proposed method. Results confirm that the established method can achieve excellent performance in early fault feature extraction.

Generalizing the Sharpe Ratio and Infinite Divisibility in Financial Markets

Investments with high Sharpe ratios tend to be fixed income investments, particularly short-term bonds. Such securities dominate income investment, but not growth investment. We generalize the Sharpe ratio to interpolate smoothly between risk-averse and risk-seeking behaviors, with the traditional Sharpe ratio as a special case. The generalized ratios may be used to optimize portfolios within a lifestyle strategy or a lifecycle strategy. We demonstrate that the Sharpe ratio has an interpretation connected to value at risk (VaR), if returns are normally distributed. We study broad market indices and indicators for US stocks, US corporate bonds, gold, and Japanese stocks. Using monthly data obtained from FRED, we show that these datasets are neither normal, nor log-normal, nor stable. We argue that none of these distributions is appropriate for market data. We argue instead for using infinitely divisible distributions, and fit Pearson distributions to the data.

COVID-19 vaccine results might inform malaria vaccine strategies

COVID-19 vaccine results might inform malaria vaccine strategies

A LITERATURE REVIEW ON MITIGATION STRATEGIES FOR ELECTRICAL COMPONENT OBSOLESCENCE IN MILITARY-BASED SYSTEMS

The aim of this research is to conduct an all-inclusive investigation on past studies of obsolescence, the issues involved, and tactics for mitigation in military-based systems. This research investigates four categories: 1. Obsolescence Consequences, 2. Life Cycle Stages and Strategies for Life Cycle Management, 3. Design for Obsolescence and Cost Optimisation, and 4. Management and Tools. A quantitative approach was used to determine the key topics of the 55 articles used in this literature review. A keyword and topic matrix was used to determine the six main areas of concern in current research, and then broken down further into the four categories discussed in this paper. A deep dive into the literature shows that the main areas of concern for obsolescence are cost optimisation, obsolescence management, system life cycle, design/system refresh planning, architecture/open systems, and end-of-life (EOL) predictions. In the EOL predictions category, only one article proposed the idea of machine learning as a forecasting method. This effort suggests a need for a more streamlined management approach to tackling obsolescence. Newer research shows an interest shift from system life cycle management towards forecasting techniques and looking towards future proactive management improvements. This study demonstrates opportunities and challenges for entities dealing with component obsolescence and methods for minimising the issues that go along with it. This paper identifies current practices for obsolescence management, and points to areas for further research development. Keywords Obsolescence; diminishing manufacturing sources and material shortages (DMSMS); forecasting; electrical component; machine learning