Fresh Resources Research Articles

Ephemeral-habitat colonization and neotropical species richness of Caenorhabditis nematodes

BackgroundThe drivers of species co-existence in local communities are especially enigmatic for assemblages of morphologically cryptic species. Here we characterize the colonization dynamics and abundance of nine species of Caenorhabditis nematodes in neotropical French Guiana, the most speciose known assemblage of this genus, with resource use overlap and notoriously similar external morphology despite deep genomic divergence.MethodsTo characterize the dynamics and specificity of colonization and exploitation of ephemeral resource patches, we conducted manipulative field experiments and the largest sampling effort to date for Caenorhabditis outside of Europe. This effort provides the first in-depth quantitative analysis of substrate specificity for Caenorhabditis in natural, unperturbed habitats.ResultsWe amassed a total of 626 strain isolates from nine species of Caenorhabditis among 2865 substrate samples. With the two new species described here (C. astrocarya and C. dolens), we estimate that our sampling procedures will discover few additional species of these microbivorous animals in this tropical rainforest system. We demonstrate experimentally that the two most prevalent species (C. nouraguensis and C. tropicalis) rapidly colonize fresh resource patches, whereas at least one rarer species shows specialist micro-habitat fidelity.ConclusionDespite the potential to colonize rapidly, these ephemeral patchy resources of rotting fruits and flowers are likely to often remain uncolonized by Caenorhabditis prior to their complete decay, implying dispersal-limited resource exploitation. We hypothesize that a combination of rapid colonization, high ephemerality of resource patches, and species heterogeneity in degree of specialization on micro-habitats and life histories enables a dynamic co-existence of so many morphologically cryptic species of Caenorhabditis.

Synthesis of Material Interception Networks with P-Graph

A P-graph model was recently developed for direct reuse/recycle scheme for both in-plant resource conservation networks (RCNs) and inter-plant RCNs (IPRCNs). The proposed P-graph model allows visualization which expedites the assessment of optimal and near-optimal solutions. In this paper, the P-graph model will be extended to material interception schemes, i.e., material regeneration and pre-treatment. Material regeneration involves the use of purification unit for quality improvement of the process sources before they are reused/recycled to the sinks. Pre-treatment processes, on the other hand, involve the purification of fresh resources for use in processes with stringent quality requirement. Two literature case studies are solved to demonstrate the newly extended model.

On a Long Term Strategy for the Success of Nuclear Power

The current generation of nuclear reactors are evolutionary in design, mostly based on the technology originally designed to power submarines, and dominated by light water reactors. The aims of the Generation IV consortium are driven by sustainability, safety and reliability, economics, and proliferation resistance. The aims are extended here to encompass the ultimate and universal vision for strategic development of energy production, the “perpetuum mobile”—at least as close as possible. We propose to rethink nuclear reactor design with the mission to develop an innovative system which uses no fresh resources and produces no fresh waste during operation as well as generates power safe and reliably in economic way. The results of the innovative simulations presented here demonstrate that, from a theoretical perspective, it is feasible to fulfil the mission through the direct reuse of spent nuclear fuel from currently operating reactors as the fuel for a proposed new reactor. The produced waste is less burdensome than current spent nuclear fuel which is used as feed to the system. However, safety, reliability and operational economics will need to be demonstrated to create the basis for the long term success of nuclear reactors as a major carbon free, sustainable, and applied highly reliable energy source.

Decreased plant productivity resulting from plant group removal experiment constrains soil microbial functional diversity.

Anthropogenic environmental changes are accelerating the rate of biodiversity loss on Earth. Plant diversity loss is predicted to reduce soil microbial diversity primarily due to the decreased variety of carbon/energy resources. However, this intuitive hypothesis is supported by sparse empirical evidence, and most underlying mechanisms remain underexplored or obscure altogether. We constructed four diversity gradients (0-3) in a five-year plant functional group removal experiment in a steppe ecosystem in Inner Mongolia, China, and quantified microbial taxonomic and functional diversity with shotgun metagenome sequencing. The treatments had little effect on microbial taxonomic diversity, but were found to decrease functional gene diversity. However, the observed decrease in functional gene diversity was more attributable to a loss in plant productivity, rather than to the loss of any individual plant functional group per se. Reduced productivity limited fresh plant resources supplied to microorganisms, and thus, intensified the pressure of ecological filtering, favoring genes responsible for energy production/conversion, material transport/metabolism and amino acid recycling, and accordingly disfavored many genes with other functions. Furthermore, microbial respiration was correlated with the variation in functional composition but not taxonomic composition. Overall, the amount of carbon/energy resources driving microbial gene diversity was identified to be the critical linkage between above- and belowground communities, contrary to the traditional framework of linking plant clade/taxonomic diversity to microbial taxonomic diversity.

Landscape Serving Education—Inspirations from Green School Yard in San Francisco

This research paper was written as a requirement of LA 514 The Professional Practice of Landscape Architecture, Master of Landscape Architecture Program, Illinois Institute of Technology for Professor Mary Pat Mattson. In the course of my exploration, I realized that Miller’s design of Green school yards in San Francisco were a highly collaborative effort with schools, communities and organizations. The green schoolyards, including edible gardens, not only extend the outdoor classroom which has become more and more popular in the world, but also provide educational purpose, physical training, awareness of food resources and fresh food resources. This paper is going to figure out the following questions: what is the designer’s responsibility and role in the design process? How does the green schoolyard design influence the work? How is the collaboration between community, design team, school and Government? What are proposed politics and culture?

Efficacy of Orientation Training Programme in Organizations

In today’s cut-throat competitive world, attracting and sustaining the proficient employees is the pinnacle priority for all the organizations. Here the induction training plays a crucial role for an organization to attain its long term competitiveness. Induction training bridges the gap between fresh recruits and organizations. It will help both the organizations and fresh human resources to build up a healthy relationship between them. “Training is an organized activity for increasing the knowledge and skills of people for a definite purpose. The trainees acquire technical knowledge, skills and problem solving ability by undergoing the training programme. Training makes a very important contribution to the development of the organization’s human resources and hence to the achievement of its aims and objectives. Training needs to be effectively managed so that the right training is given to the right people, in the right form, at the right time and at the right costs” (Dr.B.Rathan Reddy, Edition 2012) “ Training is the act of increasing the knowledge and skill of an employee for doing a particular job” (Edwin B.Flippo) “ The organized procedure by which people learns knowledge and skill for a definite purpose” (Dale S.Beach).

History-Register Automata

Programs with dynamic allocation are able to create and use an unbounded number of fresh resources, such as references, objects, files, etc. We propose History-Register Automata (HRA), a new automata-theoretic formalism for modelling such programs. HRAs extend the expressiveness of previous approaches and bring us to the limits of decidability for reachability checks. The distinctive feature of our machines is their use of unbounded memory sets (histories) where input symbols can be selectively stored and compared with symbols to follow. In addition, stored symbols can be consumed or deleted by reset. We show that the combination of consumption and reset capabilities renders the automata powerful enough to imitate counter machines, and yields closure under all regular operations apart from complementation. We moreover examine weaker notions of HRAs which strike different balances between expressiveness and effectiveness.

Ethical leadership resources in southern Africa's Sesotho-speaking culture and in King Moshoeshoe I

ABSTRACTThe problem addressed in this paper is the need for fresh resources for enhanced ethical leadership in South Africa and elsewhere in Africa. To respond to that problem the paper uses two valuable but insufficiently known sources from the culture of the Sesotho-speaking people of southern Africa, now found in Lesotho and much of South Africa's Free State province. The first one is a set of concepts that pertain to sound human relationships. The second one is Basotho history in the persons of the founding monarch of the Basotho nation, King Moshoeshoe I (ca. 1786–1870) and to a lesser extent his remarkable mentor, Chief Mohlomi (ca. 1720–1815). A final section of this paper draws these sources together into a set of contentions about successful leadership in which ethical quality is seen as paramount.

Relative concentration based pinch analysis for targeting and design of hydrogen and water networks with single contaminant

Hydrogen and water are important resources for refineries. Pinch based conceptual method is an effective tool for fresh resource conservation of hydrogen and water networks. A novel graphical method is proposed to identify the minimum consumption of fresh resource and design the network for both hydrogen and water networks with single contaminant. This method replaces traditional total flow rate and absolute concentration constraints with hydrogen load and relative concentration, constructing the composite curves in contaminant load versus hydrogen load diagram to perform the targeting and design process. Furthermore, the proposed method can be reinforced by integrating purification reuse, conserving more fresh hydrogen and further reducing the waste discharge. This new method is visible, simple and easy to understand, suitable to both hydrogen and water networks. Three cases are studied to illustrate its application.

Simultaneous heat integrated resource allocation network targeting for total annual cost considering non-isothermal mixing

This paper introduces a new approach for targeting minimum total annual operating cost of heat integrated resource allocation network. This cost includes fresh resource and utility costs. Primary analyses are led to specify an adequate search space for the variables. A mixed integer linear programming (MILP) model is presented to design the heat integrated resource allocation network. The objective function includes fresh resource, waste discharge and utilities. Heat integration is realized with a modified transshipment model, where a predefined temperature scale is built in order to account for non-isothermal mixing.

Efficient gas processing key to economic growth

apid economic growth, whether in newer territories such as China and India or mature markets such as post-recession Europe, is generating huge demand for oil and gas to power everything from construction to transport. At the same time, the discovery of fresh resources such as shale oil and gas is creating significant opportunities for companies such as Pentair, a key player in the filtration and separation side of the industry. Here we explain how it is taking advantage of this potential.

Hydrogen networks synthesis considering separation performance of purifiers

In hydrogen networks, purifiers are quite often used to reduce operating costs. They should be properly integrated with the whole network in order to maximize the benefit. In this paper, a graphical method is proposed for targeting the minimum fresh resource consumption of hydrogen networks considering separation performance of purifiers. The material balance of the whole hydrogen network shows that the extent of fresh hydrogen reduction is subject to the maximum hydrogen surplus. Based on such observation, the mass transfer triangle is developed to describe the hydrogen transformation from maximum hydrogen surplus to fresh hydrogen. With both the purity and the flow rate of purification streams optimized, the minimum fresh hydrogen consumption can be determined through the proposed graphical method. Two cases are studied to illustrate the proposed methodology.

Designing optimal bioethanol networks with purification for integrated biorefineries

Bioethanol networks with purification for processing pathways in integrated biorefineries are targeted and designed in this work by an analytical approach not requiring graphical constructions. The approach is based on six fundamental equations involving eight variables: two balance equations for the stream flowrate and the bioethanol load over the total network system; one equation for the above-pinch bioethanol load being picked up by the minimum fresh resource and the purified stream; and three equations for the purification unit. A solution strategy is devised by specifying the two variables associated with the purifier inlet stream. Importantly, continuous targeting is then possible over the entire purifier inlet flowrate range on deriving elegant formulae for the remaining six variables. The Unified Targeting Algorithm (UTA) is utilized to establish the minimum fresh bioethanol resource flowrate and identify the pinch purity. The fresh bioethanol resource flowrate target is shown to decrease linearly with purifier inlet flowrate provided the pinch is held by the same point. The Nearest Neighbors Algorithm (NNA) is used to methodically synthesize optimal networks matching bioethanol demands and sources. A case study of a biorefinery producing bioethanol from wheat with arabinoxylan (AX) coproduction is presented. It illustrates the versatility of the approach in generating superior practical designs with up to nearly 94% savings for integrated bioethanol networks, both with and without process constraints, for grassroots as well as retrofit cases.

Heat integrated resource conservation networks without mixing prior to heat exchanger networks

Abstract This paper presents a generic approach for the synthesis of heat integrated resource conservation networks (HIRCNs) of the fixed flow rate problem, where process sources linked directly to process sinks without any prior mixing. The mixed integer non-linear program (MINLP) formulation complemented by floating pinch concept was developed to determine the optimum fresh material resources as well as hot and cold energy utilities. The proposed approach is applicable for both concentration- and property-based direct reuse/recycle system with variable operating parameters (i.e. flow rates, temperatures and properties). Three literature case studies are solved to illustrate the proposed approach.

Optimal reconfiguration of water networks based on properties

This paper presents a mathematical programming model for the reconfiguration of existing water networks based on the stream properties that impact the performance of the process units and the environment. To develop an improved configuration, the model simultaneously evaluates the repiping of the existing network through the placement/reassignment of the existing treatment units, and the addition of new treatment units while addressing environmental constraints. The model also accounts for the options of process modification and increased capacity of the plant. The objective function of the optimization model seeks to minimize the total annualized cost of the system which incorporates the capital investment associated with process retrofitting and the operating cost which includes the cost of fresh resources. The applicability of the proposed model is illustrated through several case studies.

Morphological and molecular characterization of Diplodia seriata, the causal agent of canker and twig dieback disease on mulberry in Iran

Mulberries are cultivated for different purposes: for feeding larvae of silkworm, Bombyx mori, as fresh and dry food resources, in wood instrument industry, in pharmaceutical industry and as outdoor ornamental trees in Iran. In recent years, twig and branch canker disease symptoms have been noticed on mulberry trees in northwestern parts of Iran. Diplodia isolates were repeatedly recovered from symptomatic tissues. Based on cultural and morphological features, the isolates were identified as Diplodia seriata. The identity of the isolates was further confirmed using sequence data from internal transcribed spacer (ITS)-rDNA and ef-1α gene. A phylogenetic analysis using ITS sequence data clustered the isolates obtained in this study together with known Diplodia seriata isolates of other woody hosts from GenBank. Inoculation studies carried out on white mulberry twigs using an excised shoot method revealed that the isolates are pathogenic on this host. D. seriata have been reported from other woody host plant species such as Juglans nigra and Vitis vinifera in Iran, however, to the best of our knowledge, the occurrence of D. seriata on mulberry trees is new for Iran. The distribution and reaction of different Morus spp. to D. seriata remain to be studied.

Synthesis of Heat Integrated Resource Conservation Networks with Varying Operating Parameters

This paper presents the synthesis of heat integrated resource conservation networks (HIRCNs), covering both concentration- and property-based direct reuse/recycle systems. This newly proposed method adopts the targeting concept of the insight-based pinch approach where the minimum consumption of fresh resources and energy utilities is targeted prior to the detailed HIRCN design. Furthermore, this method is capable of handling HIRCN problems with varying operating range of process parameters (i.e., flow rates, temperatures, and properties). The proposed method is formulated as a mixed integer nonlinear program (MINLP). As the temperature of stream is uncertain, the floating pinch concept is adopted to identify hot and cold utilities. Besides, a recently developed discretization approach is also used to solve the MINLP problem. Three literature case studies are solved to illustrate the proposed method.

Evolutionary Graphical Approach for Simultaneous Targeting and Design of Resource Conservation Networks with Multiple Contaminants

Large consumption and soaring demand have led to huge deficiencies in the availability of fresh resources such as hydrogen and water in the chemical industries throughout the world, casting a long shadow over their operating margins. More than ever the efficient use and conservation of fresh resources plays a pivotal role in many large-scale chemical processing enterprises such as refinery operations. This paper addresses the target of minimum fresh resource demand and design of resource conservation networks with multiple contaminants. With a view to the allocation of a single sink, a triangle rule is deduced from an existing design technique. In order to describe the quality difference of sources and sinks according to different impurity concentrations, the nearest neighbor algorithm for resource conservation networks with single contaminant is generalized to the case of resource conservation networks with multiple contaminants. On the basis of the new nearest neighbor algorithm, a ranking rule is estab...

Evaluation of antiangiogenic and antiproliferative potential of the organic extract of green algae chlorella pyrenoidosa

Objective:algae isolates obtained from fresh and marine resources could be one of the richest sources of novel bioactive secondary metabolites expected to have pharmaceutical significance for new drug development. This study was conducted to evaluate the antiangiogenic and antiproliferative activity of Chlorella pyrenoidosa in experimental models of angiogenesis and by MTT assay.Materials and Methods:lyophilized extract of C. pyrenoidosa was extracted using dichloromethane/methanol (2:1), concentrated and vacuum evaporated to obtain the dried extract. The crude extract was evaluated in the vascular endothelial growth factor (VEGF)-induced angiogenesis in in ovo chick chorioallantoic membrane assay (CAM) at various concentrations (n = 8) using thalidomide and normal saline as positive and untreated control groups, respectively. The crude extract was also subjected to the antiangiogenic activity in the silver nitrate/potassium nitrate cautery model of corneal neovascularization (CN) in rats where topical bevacizumab was used as a positive control. The vasculature was photographed and blood vessel density was quantified using Aphelion imaging software. The extract was also evaluated for its anti proliferative activity by microculture tetrazolium test (MTT) assay using HeLa cancer cell line (ATCC).Results:VEGF increased the blood vessel density by 220% as compared to normal and thalidomide treatment decreased it to 67.2% in in ovo assay. In the in-vivo CN model, the mean neovascular density in the control group, the C. pyrenoidosa extract and bevacizumab group were found to be 100%, 59.02%, and 32.20%, respectively. The Chlorella pyrenoidosa extract negatively affected the viability of HeLa cells. An IC50 value of the extract was 570 μg/ml, respectively.Conclusion:a significant antiangiogenic activity was observed against VEGF-induced neovascularization and antiproliferative activity by MTT assay. In this study, it could be attributed that the activity may be due to the presence of secondary metabolites in the C. pyrenoidosa extract.

A generalised guideline for process changes for resource conservation networks

In the past one and a half decades, resource conservation network (RCN) synthesis has been well accepted by both academics and industrial practitioners in enhancing sustainability aspect for the process industry. Various insight-based pinch analysis and mathematical optimisation techniques have been proposed to synthesise optimum RCN. For the former, the developments to date have been focusing on various targeting and design tools, with very little emphasis on the systematic assessment of process changes. The latter involves the modification of process operating conditions (e.g., flowrate, concentration, temperature, etc.), which leads to further reduction of minimum fresh resource flowrates. In this study, the plus-minus principle in heat exchanger network synthesis is extended for use with graphical targeting tool in assessing opportunities for process changes in the RCN of fixed-flowrate problems, aiming to further reduce its minimum fresh resource flowrate. Literature examples are used for illustration.