growth constraint
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2022 ◽  
Author(s):  
Martin Rylance ◽  
Yaroslav Korovaychuk

Abstract For as long as we have been performing hydraulic fracturing, we have been trying to ensure that we stay out of undesirable horizons, potentially containing water and/or gas. The holy grail of hydraulic fracturing, an absolute control of created fracture height, has eluded the industry for more than 70 years. Of course, there have been many that have claimed solutions, but all the marketed approaches have at best merely created a delay to the inevitable growth and at worst been a snake-oil approach with little actual merit. Fundamentally, the applied techniques have attempted to delay or influence the underlying equations of net-pressure and stress variation; but having to ultimately honour them and by doing so then condemned themselves to limited success or outright failure. Fast forward to 2020, and a reassessment of the relative importance of height-growth constraint and what may have changed to help us achieve this. The development of unconventionals are focused on creating as much surface area as possible in micro/nano-Darcy environments, across almost any phase, but with typically poor line of sight to profit. However, the more valuable business of conventional oil and gas is working in thinner and thinner reservoirs with an often-deteriorating permeability, but with a significantly higher potential economic return. What unconventional has successfully delivered however, is a rapid deployment and acceleration in a range of completion technologies that were unavailable just a few years ago. We will demonstrate that these technologies potentially offer the capability of finally being able to control fracture height-growth. Consideration of a range of previously applied height-growth approaches will demonstrate how they attempted to fool or fudge height growth creation mechanisms. With this clarity, we can consider what advances in completion technology may offer in terms of delivering height growth control. We suggest that with the technology and approaches that are currently available today, that height-growth control is finally within reach. We will go on to describe a multi-well Pilot program, in deployment and execution in 2020/021 in Western Siberia; where billions of barrels remain to be recovered in thin oil-rim, low permeability sandstone reservoirs below gas or above water. A comprehensive assessment of the myriad of height-growth approaches that have been utilized over the last 70 years was performed, but in each case demonstrated the fallibility and limitations of each of these. However, rather than the interpretation that such control is not achievable, instead we will show a mathematically sound approach, along with field data and evidence that this is possible. The presentation will demonstrate that completion advances over the last 10 - 15 years make this approach a reality in the present day; and that broader field implementation is finally within reach.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Adlin Masood ◽  
Aisyah Zaidi

Purpose This study aims to identify and examine the growth constraints of the halal cosmetics ecosystem in which SMEs are operating in, with special focus on the situation in Malaysia. Design/methodology/approach The study adopted a qualitative methodology consisting of a systematic literature review and interviews with selected consumers and policymakers. The instruments were developed based on cybernetics and a systems-based approach, which allows for the understanding of the dynamics of growth variables in the halal cosmetics ecosystem. Based on data gathered, their relationships were mapped and major growth constraints were identified. Findings Cybernetics and systems approach coupled with growth diagnostics framework has enabled identification of comprehensive growth constraint variables for halal cosmetics ecosystem and mapping of growth constraints (variables) in a relationships network. The study found that the enforcement activities of the National Pharmaceutical Research Agency (Cosmetics Unit) directly affect five growth constraints and is associated with three other growth constraint variables; subsequently the most binding growth constraint. The relationship network derived from the mapping of the growth constraints indicated that changes in the behaviour of any element will affect the overall operations of the ecosystem. Research limitations/implications While the cosmetics industry is large and varied, this study is centred on halal colour cosmetics only. The growth constraint variables studied are those chosen by researchers and other growth constraints could be studied to guide policymakers. Future research can revolve around other halal cosmetics business sectors; impact of IR4.0 technology, COVID-19 pandemic impact; crisis and risk management issues, in the halal cosmetics industry. Practical implications The results derived from the cybernetics analysis affirms the “outside-in” marketing perspective, thus stakeholders should continuously monitor changes in the halal cosmetics ecosystem to ensure to ensure sustainability and profitability. Small and medium enterprises (SMEs) and policymakers can initiate pre-emptive actions by conducting simulations of various situations on the halal ecosystem. Social implications Enabled to simulate the effect of changes to the halal cosmetics ecosystem, stakeholders are able to take intervention initiatives, safeguard accessibility to halal cosmetics and make the halal cosmetics industry sustainable. Originality/value To the best of the authors’ knowledge, this is the first comprehensive research to identify the growth constraints of the halal cosmetics industry in Malaysia that focusses on three groups of stakeholders (consumers, SMEs and government institutions) concurrently. The growth constraints relationship network of the halal cosmetics ecosystem can be further used to simulate the impact of changes within the system.


2020 ◽  
Vol 73 ◽  
pp. 49-56
Author(s):  
Jonty Mills ◽  
Sarah Jackman ◽  
Chikako Van Koten ◽  
Michael Cripps

The leaf-feeding beetle, Cassida rubiginosa, is an oligophagous biocontrol agent capable of feeding on most species in the tribe Cardueae (thistles and knapweeds). The beetle was released in New Zealand in 2007, primarily to control Cirsium arvense (Californian thistle), with the recognition that it had potential to control multiple thistle weeds. The objective of this study was to test the impact of different densities of Cassida rubiginosa larvae (0, 50, 100, or 200 per plant) on the growth and reproductive performance of the annual thistle weed, Carduus pycnocephalus (slender winged thistle). Since the effectiveness of biocontrol agents is often enhanced when plants are stressed, different levels of growth constraint were imposed by growing the weed in different pot sizes (0.5, 1, 5, and 12 litres). We hypothesised that feeding damage by Cassida rubiginosa larvae would have a greater impact on the weed when grown in smaller pots, since root growth would be constrained, and the weed’s ability to compensate for feeding damage would be restricted. Contrary to our hypothesis, pot size had no effect on feeding damage by Cassida rubiginosa on Carduus pycnocephalus. As expected, most measures of plant performance increased with larger pot sizes, including plant height, biomass, and the number of seedheads per plant. The results of this study indicate that Cassida rubiginosa is unlikely to contribute to the control of Carduus pycnocephalus. Additional oligophagous biocontrol agents targeting the rosette stage and seed production should be considered for release in New Zealand.


2019 ◽  
Vol 95 (8) ◽  
Author(s):  
Soon Hwee Ng ◽  
Michael Stat ◽  
Michael Bunce ◽  
Stephen J Simpson ◽  
Leigh W Simmons

ABSTRACTProteins and carbohydrates have profound impacts on the ecology of gut microbiota, but disentangling the single and interactive effects of different dietary constituents is challenging. Here, we used a multidimensional approach, the Geometric Framework, to study the interactions between nutrition and bacterial abundances with respect to protein and carbohydrate intakes in field cricket, Teleogryllus oceanicus. Our study revealed that species richness decreased as crickets consumed more macronutrients, and species evenness peaked at high intake of protein-rich diets. Sex and protein:carbohydrate (P:C) ratios in diets were the primary factors influencing the gut bacterial community, but most of the microbial operational taxonomic units (OTUs) that were significantly different between males and females were present in low abundance. In contrast, protein intake had a greater influence than carbohydrate consumption on the relative abundances of the core bacterial taxa, as an increase in dietary protein availability could remove the growth constraint imposed by limited nitrogen. Taken together, the use of the Geometric Framework provides a deeper insight into how nutritional intakes influence the relative abundances of gut microbes, and could be a useful tool to integrate the study of gut microbiome and fitness traits in a host.


2014 ◽  
Vol 2014 (1) ◽  
pp. 29-39 ◽  
Author(s):  
Matjaž Volk ◽  
Polona Trefalt

2003 ◽  
Vol 31 (3) ◽  
pp. 584-586 ◽  
Author(s):  
C.J. Potter ◽  
L.G. Pedraza ◽  
H. Huang ◽  
T. Xu

We have identified three groups of growth-constraint genes using mosaic genetic screens in Drosophila melanogaster, including PTEN (phosphatase and tensin homologue deleted on chromosome 10), and the tuberous sclerosis complex (TSC) genes, Tsc1 and Tsc2. Our studies show that all three groups of genes participate in mechanisms that regulate organ and organism size in animals. We propose that mechanisms of organ size control are critical targets for diseases, such as tumorigenesis, which require an increase in tissue size and total mass, and for evolutionary events that alter the size of organisms. Using genetic and biochemical methods, we have shown that Tsc1 and Tsc2 function in the insulin/phosphoinositide 3-kinase (PI3K)/Akt pathway. We have shown that Akt regulates the Tsc1–Tsc2 complex by directly phosphorylating Tsc2. We have shown further that S6 kinase (S6K) is a downstream component of the PI3K/Akt/TSC pathway and reduction of S6K activity can block TSC defects. Recent studies from many laboratories have now confirmed our findings in mice, rats and human patients, and have shown that drugs that antagonize S6K activities, such as rapamycin, diminish tumours in TSC-deficient mice and rats. Clinical trials based on these findings have begun. Given that other components of the pathway, such as PTEN, are also mutated in a large number of cancer patients and that these components regulate intracellular insulin signalling, therapeutics based on the knowledge of the pathway could have effects beyond the TSC patient population.


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