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Suwal, Naresh, Alban Kuriqi, Xianfeng Huang, João Delgado, Dariusz Młyński, and Andrzej Walega. "Environmental Flows Assessment in Nepal: The Case of Kaligandaki River." Sustainability 12, no. 21 (October 22, 2020): 8766. http://dx.doi.org/10.3390/su12218766.
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Environmental flow assessments (e-flows) are relatively new practices, especially in developing countries such as Nepal. This study presents a comprehensive analysis of the influence of hydrologically based e-flow methods in the natural flow regime. The study used different hydrological-based methods, namely, the Global Environmental Flow Calculator, the Tennant method, the flow duration curve method, the dynamic method, the mean annual flow method, and the annual distribution method to allocate e-flows in the Kaligandaki River. The most common practice for setting e-flows consists of allocating a specific percentage of mean annual flow or portion of flow derived from specific percentiles of the flow duration curve. However, e-flow releases should mimic the river’s intra-annual variability to meet the specific ecological function at different river trophic levels and in different periods over a year covering biotas life stages. The suitability of the methods was analyzed using the Indicators of Hydrological Alterations and e-flows components. The annual distribution method and the 30%Q-D (30% of daily discharge) methods showed a low alteration at the five global indexes for each group of Indicators of Hydrological Alterations and e-flows components, which allowed us to conclude that these methods are superior to the other methods. Hence, the study results concluded that 30%Q-D and annual distribution methods are more suitable for the e-flows implementation to meet the riverine ecosystem’s annual dynamic demand to maintain the river’s health. This case study can be used as a guideline to allocate e-flows in the Kaligandaki River, particularly for small hydropower plants.
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Ćosić-Flajsig, Gorana, Ivan Vučković, and Barbara Karleuša. "An Innovative Holistic Approach to an E-flow Assessment Model." Civil Engineering Journal 6, no. 11 (November 1, 2020): 2188–202. http://dx.doi.org/10.28991/cej-2020-03091611.
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River water resources provide a wide range of necessary ecosystem services, including regulating, provisioning, supporting and cultural services. Ecosystem services are linked to an appropriate level of functionality of river water resource processes, which can be connected with river basin environmental objectives. Environmental objectives can be achieved only if appropriate flow and sediment regimes and related river morphology quality are guaranteed. The obligation to define environmental flow (E-flow) in the European Union Water Framework Directive European (WFD) is not explicit, and the implementation of the WFD is more focused on water quality. Considering the specific climatic, hydrographic and hydrological conditions and the definition of E-flow, each EU country has developed procedures for their investigation and determination. In the Republic of Croatia, no methodology has been elaborated, nor is there any legal regulation to define E-flow downstream of a dam or water intake site. This paper presents the significant pressures that have affected the transboundary rural Sutla River basin between Croatia and Slovenia. These pressures can cause changes in the hydrological regime and biological elements of water quality. The holistic approach defines the E-flow for a profile on the Sutla River by linking hydrological, morphological, and ecological characteristics based on the exploration of the Sutla River and its biological communities. The full implementation of a holistic approach and the transition to Level III of the E-flow definition requires the enhancement of exploratory hydrological and biological monitoring that enables the use of habitat modelling. Doi: 10.28991/cej-2020-03091611 Full Text: PDF
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Wei, June, Binshan Lin, and Meiga Loho-Noya. "Development of an E-Healthcare Information Security Risk Assessment Method." Journal of Database Management 24, no. 1 (January 2013): 36–57. http://dx.doi.org/10.4018/jdm.2013010103.
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This paper developed a method to assess information security risks in e-healthcare. Specifically, it first developed a static E-Healthcare Information Security Risk (EHISR) model to present thirty-three security risk factors by identifying information security threats and their sources in e-healthcare. Second, a dynamic E-Healthcare Information Flow (EHIF) model was developed to logically link these information risk factors in the EHISR model. Pattern analysis showed that information security risks could be classified into two levels, and versatility analysis showed that the overall security risks for eight information flows were close with a range from 55% to 86%. Third, one quantifiable approach based on a relative-weighted assessment model was developed to demonstrate how to assess the information security risks in e-healthcare. This quantitative security risk measurement establishes a reference point for assessing e-healthcare security risks and assists managers in selecting a reliable information flow infrastructure with a lower security risk level.
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de Jalón, Diego García, Martina Bussettini, Massimo Rinaldi, Gordon Grant, Nikolai Friberg, Ian G. Cowx, Fernando Magdaleno, and Tom Buijse. "Linking environmental flows to sediment dynamics." Water Policy 19, no. 2 (December 5, 2016): 358–75. http://dx.doi.org/10.2166/wp.2016.106.
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This is a policy discussion paper aimed at addressing possible alternative approaches for environmental flows (e-Flows) assessment and identification within the context of best strategies for fluvial restoration. We focus on dammed rivers in Mediterranean regions. Fluvial species and their ecological integrity are the result of their evolutionary adaptation to river habitats. Flowing water is the main driver for development and maintenance of these habitats, which is why e-Flows are needed where societal demands are depleting water resources. Fluvial habitats are also shaped by the combined interaction of water, sediments, woody/organic material, and riparian vegetation. Water abstraction, flow regulation by dams, gravel pits or siltation by fine sediments eroded from hillslopes are pressures that can disturb interactions among water, sediments, and other constituents that create the habitats needed by fluvial communities. Present e-Flow design criteria are based only on water flow requirements. Here we argue that sediment dynamics need to be considered when specifying instream flows, thereby expanding the environmental objectives and definition of e-Flows to include sediments (extended e-Flows). To this aim, a hydromorphological framework for e-Flows assessment and identification of best strategies for fluvial restoration, including the context of rivers regulated by large dams, is presented.
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Sharma, Urvashi. "Effective framework for Environmental-flows estimation for data deficient Indian rivers." Journal of Applied and Natural Science 11, no. 2 (June 10, 2019): 545–55. http://dx.doi.org/10.31018/jans.v11i2.2116.
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Data deficiency is a major problem in recommending appropriate environmental flows (e-flows) requirements for rivers in many parts of the world. Several studies have been done using a variety of e-flows assessment methodologies. Large dams and hydropower projects are major manipulators of the flow regimes resulting in degraded ecosystems ubiquitously. In India attempts have been made to develop e-flows requirements of rivers to maintain a good riverine ecosystem. Most of the studies are based on hydrological methods, which do not take all the variables affecting flow-regimes into consideration. This paper highlights the problems in assessment of e-flows and their on-ground implications in India. In this study, probable solutions to these problems are suggested a conceptual framework for data deficient areas is proposed. This framework is based upon extensive baseline surveys of fluvial morphology, ecology and of indigenous population. Framework has six steps namely: monitoring the baseline conditions, setting up objectives, hydrological analysis, ecological analysis, climatic anomalies incorporation and recommendations. Finally, e-flows recommendations are made based on hydrological studies, habitat suitability curves and area of inland water body which should be maintained in the river basin. All these recommendations are compared and suitable e-flows recommendations are made based on studied variables. The review also suggests for bottom-up approach for e-flows assessment i.e. e-flows assessment and application should be done on small tributaries of rivers in initial phase of projects and those methods which deliver satisfactory results should only be applied to larger rivers.
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Davies, Peter M., Robert J. Naiman, Danielle M. Warfe, Neil E. Pettit, Angela H. Arthington, and Stuart E. Bunn. "Flow–ecology relationships: closing the loop on effective environmental flows." Marine and Freshwater Research 65, no. 2 (2014): 133. http://dx.doi.org/10.1071/mf13110.
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Providing flows for biota and environmental processes is a challenging water management issue. For society the ability and willingness to allocate water to sustain the environment is increasingly competitive due to escalating demand and as a consequence of climate change. In response, an array of environmental flow (E-flow) methods have developed. Our view is that few E-flows have been implemented and even fewer evaluated in a research and management context. Much of our science effort in E-flows has been directed primarily at method development, with less attention being given to monitoring, evaluation and subsequent revision of E-flow strategies. Our objectives are to highlight the lack of connection between current trends in E-flow literature and theory with assessment of the efficacy and practical application of these methods. Specifically, effective E-flows need to be explicit about flow-ecology relationships to adequately determine the amount and timing of water required. We briefly outline the historical development of E-flows and discuss how serial development of methods and techniques has restricted implementation, evaluation and revision. We highlight areas where methods are lacking, such as incorporation of data on flow-ecology relationships into operational use of E-flow methods. We suggest four initial steps that will improve the applicability, implementation and ultimate success of E-flows.
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O'Brien, Gordon C., Chris Dickens, Eleanor Hines, Victor Wepener, Retha Stassen, Leo Quayle, Kelly Fouchy, James MacKenzie, P. Mark Graham, and Wayne G. Landis. "A regional-scale ecological risk framework for environmental flow evaluations." Hydrology and Earth System Sciences 22, no. 2 (February 2, 2018): 957–75. http://dx.doi.org/10.5194/hess-22-957-2018.
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Abstract. Environmental flow (E-flow) frameworks advocate holistic, regional-scale, probabilistic E-flow assessments that consider flow and non-flow drivers of change in a socio-ecological context as best practice. Regional-scale ecological risk assessments of multiple stressors to social and ecological endpoints, which address ecosystem dynamism, have been undertaken internationally at different spatial scales using the relative-risk model since the mid-1990s. With the recent incorporation of Bayesian belief networks into the relative-risk model, a robust regional-scale ecological risk assessment approach is available that can contribute to achieving the best practice recommendations of E-flow frameworks. PROBFLO is a holistic E-flow assessment method that incorporates the relative-risk model and Bayesian belief networks (BN-RRM) into a transparent probabilistic modelling tool that addresses uncertainty explicitly. PROBFLO has been developed to evaluate the socio-ecological consequences of historical, current and future water resource use scenarios and generate E-flow requirements on regional spatial scales. The approach has been implemented in two regional-scale case studies in Africa where its flexibility and functionality has been demonstrated. In both case studies the evidence-based outcomes facilitated informed environmental management decision making, with trade-off considerations in the context of social and ecological aspirations. This paper presents the PROBFLO approach as applied to the Senqu River catchment in Lesotho and further developments and application in the Mara River catchment in Kenya and Tanzania. The 10 BN-RRM procedural steps incorporated in PROBFLO are demonstrated with examples from both case studies. PROBFLO can contribute to the adaptive management of water resources and contribute to the allocation of resources for sustainable use of resources and address protection requirements.
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Lillo, G., R. Mastrullo, A. W. Mauro, and L. Viscito. "Flow boiling of R1233zd(E) in a horizontal tube: Experiments, assessment and correlation for asymmetric annular flow." International Journal of Heat and Mass Transfer 129 (February 2019): 547–61. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2018.09.117.
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Yadav, Maharshi, Govind Pandey, and Pradeep Kumar. "Environmental Flow Assessment (EFA) of Tawi River Discharge at the Jammu Location Using the Global Environmental Flow Calculator (GEFC)." Nature Environment and Pollution Technology 22, no. 2 (June 1, 2023): 1063–71. http://dx.doi.org/10.46488/nept.2023.v22i02.054.
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The water, food, and energy demands are the basic requirements of society. These demands are increasing daily due to an increase in population or lifestyle changes. To fulfill these ever-increasing demands, several water resource projects have come up which require the storage or diversion of river water. These interventions have caused widespread degradation of aquatic ecosystems. Due to the degradation of the aquatic ecosystem, several programs all around the globe began. In this series, Brisbane Declaration (2007) provided a more holistic definition of Environmental Flows (EFs) as the quantity, timing, duration, frequency, and quality of flows required to sustain freshwater, estuarine and near-shore ecosystems and the human livelihoods and well-being that depend on them. The present study was envisaged to assess for environmental flows of the Tawi river with a major objective of assessing the environmental flows of the Tawi river using the Global Environmental Flow Calculator developed by IWMI. The method provides E-Flows for different Environmental Management Classes. For the western Himalayan region, the river stretches in Environmental Management Class ‘B’ and ‘C’. The assessment provides E-Flows in two ways: (i) the percentage of Mean Annual Runoff and (ii) average monthly environmental flows. E-Flows were estimated as 42.34% to 56.96% of Mean Annual Runoff and varied from 5.73 cumecs during November to 68.23 during August.
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Zidouni, Kendil, Salah Bousbia, and Amina Mataoui. "Assessment of three turbulence model performances in predicting water jet flow plunging into a liquid pool." Nuclear Technology and Radiation Protection 25, no. 1 (2010): 13–22. http://dx.doi.org/10.2298/ntrp1001013z.
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The main purpose of the current study is to numerically investigate, through computational fluid dynamics modeling, a water jet injected vertically downward through a straight circular pipe into a water bath. The study also aims to obtain a better understanding of jet behavior, air entrainment and the dispersion of bubbles in the developing flow region. For these purposes, three dimensional air and water flows were modeled using the volume of fluid technique. The equations in question were formulated using the density and viscosity of a 'gas-liquid mixture', described in terms of the phase volume fraction. Three turbulence models with a high Reynolds number have been considered i. e. the standard k-e model, realizable k-e model, and Reynolds stress model. The predicted flow patterns for the realizable k-e model match well with experimental measurements found in available literature. Nevertheless, some discrepancies regarding velocity relaxation and turbulent momentum distribution in the pool are still observed for both the standard k-e and the Reynolds stress model.
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Chen, Ang, and Miao Wu. "Managing for Sustainability: The Development of Environmental Flows Implementation in China." Water 11, no. 3 (February 28, 2019): 433. http://dx.doi.org/10.3390/w11030433.
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Environmental flows (e-flows) are important for river protection and restoration under degraded ecological conditions. With increasing public desire for and pursuit of sustainable development, e-flows are widely used to reflect the hydrological regime requirements for sustaining freshwater ecosystems and human livelihoods. Over the past 40 years, e-flows implementation has shifted from static minimum flows to dynamic flow components. However, e-flows standards used to manage flow releases from dams are to a great extent based on expert judgement and government supervision. These attributes make it difficult to effectively implement e-flows in the non-stationary world. The primary focus of this paper is to review the history, management systems and scientific basis of e-flows in China. Firstly, the study classifies the development phases into four periods and then analyses the underpinning legal system for e-flows implementation in each period, including the laws, regulations, policies and responsible authorities. Finally, the scientific basis and methods for e-flows determination and assessment were analyzed. The study showed that: (1) e-flows have been officially regarded as ecological flow in China, which evolved from minimum flow, and the contents and connotations are still broadening; (2) currently, there are too many authorities related to e-flows and complicated legal documents in China which lead to ineffective implementation; (3) the scientific basis of e-flows is enriched from the relationship between hydrological alteration and ecological response, so that the practices will be more holistic in China. Despite the successful practices of e-flows implementation in large rivers, there are challenges for implementing future e-flows in small rivers. This study recommended that future e-flows implementation be integrated with sustainable water management by setting clear responsibilities for governments, ministries, and other stakeholders.
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Chen, Ang, Miao Wu, Dandan Shen, and Shuang Song. "Developing a Decision Support Evaluation Model Based on the Matter Element Analysis Method to Optimize the Environmental Flows in Dammed Rivers." Water 14, no. 18 (September 17, 2022): 2905. http://dx.doi.org/10.3390/w14182905.
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The large number of dams in the world has caused many ecological problems, especially in ecologically fragile areas. Appropriate environmental flow (e-flows) releases reduce stress on river ecosystems caused by the flow alterations of dams. As e-flow releasing is substantially a decision-making process, it is important to choose the right calculation method in many e-flow assessment frameworks and calculation methods or to select the proper e-flow result from many scenarios. In China, there are government guidelines to assist managers in choosing an e-flow method for their situations, but the technical components of these guidelines are too general and not very specific, even though the coverage of the framework of guidelines is comparatively complete. Thus, a high degree of subjectivity remains in the method selection, and managers are often confused about the different e-flow results and scenarios. A more detailed decision support evaluation (DSE) model which can quantify and compare the results from different calculation methods is therefore needed to provide a basic technical economy evaluation. Based on the relevant policies and the dam priority classification frameworks in China, we propose a DSE model based on the matter element analysis (MEA) method to complement the Chinese e-flow framework. First, the flow regime criteria from the related government guidelines for a variety of conservation objectives are summarized. Secondly, different scenarios of e-flows are calculated based on the formal government guidelines and using the same hydrological database. Finally, the DSE model for assessing the different e-flow scenarios are built and demonstrated. MEA helped to quantify and optimize the different results and reduce the uncertainty. The DSE model presented in this study can be applied to e-flow optimization for all dammed rivers in China and serve as a decision support tool for managers.
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Oikawa, Masayoshi, Atsushi Kobayashi, Takamasa Sato, Satoshi Suzuki, Yoshihisa Akiomi, Kazuhiko Nakazato, Hitoshi Suzuki, Shu-ichi Saitoh, and Yasuchika Takeishi. "The usefulness of combined assessment of E/E′ ratio and transmitral flow pattern to interpret cardiac condition." FUKUSHIMA JOURNAL OF MEDICAL SCIENCE 63, no. 1 (2017): 16–21. http://dx.doi.org/10.5387/fms.2016-9.
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Oikawa, Masayoshi, Atsushi Kobayashi, Hiroyuki Yamauchi, Satoshi Suzuki, Akiomi Yoshihisa, Kazuhiko Nakazato, Hitoshi Suzuki, Shu-Ichi Saitoh, and Yasuchika Takeishi. "The Usefulness of Combined Assessment of E/e′ Ratio and Transmitral Flow Pattern to Interpret Heart Condition." Journal of Cardiac Failure 20, no. 10 (October 2014): S169—S170. http://dx.doi.org/10.1016/j.cardfail.2014.07.218.
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Gu, Xin, Jian Wen, Chunlong Wang, Xing Zhang, Simin Wang, and Jiyuan Tu. "Condensation flow patterns and model assessment for R1234ze(E) in horizontal mini/macro-channels." International Journal of Thermal Sciences 134 (December 2018): 140–59. http://dx.doi.org/10.1016/j.ijthermalsci.2018.08.006.
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Gunn, Iain, and Andrew W. Woods. "On the flow of buoyant fluid injected into an aquifer with a background flow." Journal of Fluid Mechanics 706 (July 12, 2012): 274–94. http://dx.doi.org/10.1017/jfm.2012.253.
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AbstractWe study the dispersal of a plume of incompressible buoyant fluid injected into a confined inclined aquifer in which there is a background flow. We assume that, to prevent pressure buildup in the system, there is an outflow from the aquifer, with flux equal to the injection flux, through a producing well. Using the method of characteristics, we identify that the trajectory of the plume of injected fluid depends on the magnitudes of both the injection flux ${Q}_{I} $ and the background aquifer flux ${Q}_{A} $ relative to the buoyancy-driven exchange flow of injected and original fluid within the aquifer ${Q}_{E} $, on the direction of the background aquifer flow, and on whether the producing well lies upslope or downslope from the injecting well. We find the values of the controlling parameters ${Q}_{I} / {Q}_{E} $ and ${Q}_{A} / {Q}_{E} $ for which all injected fluid flows up-dip, for which the injected fluid partitions into a component moving up-dip and a component moving down-dip, and for which all injected fluid flows down-dip. A key learning from the analysis is that there may be very different plume trajectories when a buoyant fluid is injected into a confined, inclined aquifer, and prediction of the trajectory depends on knowledge of the background flow as well as the injection rate and location of the producing wells. In the process of ${\mathrm{CO} }_{2} $ sequestration, this range of initial plume geometries can inform analysis of longer-term geological storage and assessment of the risk of activating different possible leakage pathways to the surface.
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O’Brien, Gordon C., Chris Dickens, Chris Baker, Retha Stassen, and Frank van Weert. "Sustainable Floodplains: Linking E-Flows to Floodplain Management, Ecosystems, and Livelihoods in the Sahel of North Africa." Sustainability 12, no. 24 (December 17, 2020): 10578. http://dx.doi.org/10.3390/su122410578.
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Floodplains are particularly important in the semi-arid region of the Sub-Sahelian Africa. In this region, water governance is still being developed, often without adequate information and technical capacity for good, sustainable water resource management. However, water resources are being allocated for use with minimal sustainability considerations. Environmental flows (e-flows) include the quantity and timing of flows or water levels needed to meet the sustainable requirements of freshwater and estuarine ecosystems. Holistic regional scale e-flows linked to floodplain management can make a noticeable contribution to sustainable floodplain management. The Inner Niger Delta (IND) in Mali is an example of a vulnerable, socio-ecologically important floodplain in the Sahel region of North Africa that is being developed with little understanding of sustainability requirements. Although integrally linked to the Upper Niger River catchment, the IND sustains a million and half people within the region and exports food to surrounding areas. The flooding of the Delta is the engine of the socio-economic development as well as its ecological integrity. This paper aims to demonstrate the contribution that holistic regional e-flow assessment using the PROBFLO approach has to achieving floodplain sustainability. This can be achieved through the determining the e-flow requirements to maintain critical requirements of the ecosystems and associated services used by local vulnerable human communities for subsistence and describing the socio-ecological consequences of altered flows. These outcomes can contribute to the management of the IND. In this study, the socio-ecological consequences of altered flows have been evaluated by assessing the risk of alterations in the volume, duration, and timing of flows, to a number of ecological and social endpoints. Based on the risk posed to these endpoints by each scenario of change, an e-flow of 58% (26,685 million cubic meters (MCM) of water annually) was determined that would protect the ecosystem and maintain indicator components at a sustainable level. These e-flows also provide sustainable services to local communities including products for subsistence and limit any abnormal increases in diseases to the vulnerable African communities who live in the basin. Relative risk outputs for the development scenarios result in low-to-high-risk probabilities for most endpoints. The future development scenarios include insufficient flows to maintain sustainability during dry or low-flow periods with an increase in zero flow possibilities. Although unsuitable during the low-flow or dry periods, sufficient water is available through storage in the basin to meet the e-flows if these scenarios were considered for implementation. The IND is more vulnerable to changes in flows compared to the rivers upstream of the IND. The e-flow outcomes and consequences of altered flow scenarios has contributed to the management of vulnerable IND floodplains and the requirements and trade-off considerations to achieve sustainability.
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Yamashita, Yasunobu, Takanori Yoshikawa, Hirofumi Yamazaki, Yuki Kawaji, Takashi Tamura, Keiichi Hatamaru, Masahiro Itonaga, et al. "A Novel Endoscopic Ultrasonography Imaging Technique for Depicting Microcirculation in Pancreatobiliary Lesions without the Need for Contrast-Enhancement: A Prospective Exploratory Study." Diagnostics 11, no. 11 (October 30, 2021): 2018. http://dx.doi.org/10.3390/diagnostics11112018.
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Detective flow imaging endoscopic ultrasonography (DFI-EUS) provides a new method to image and detect fine vessels and low-velocity blood flow without using ultrasound contrast agents. The aim of this study was to evaluate the utility of DFI-EUS for pancreatobiliary lesions and lymph nodes. Between January 2019 and January 2020, 53 patients who underwent DFI-EUS, e-FLOW EUS, and contrast-enhanced EUS were enrolled. The ability of DFI-EUS and e-FLOW EUS to detect vessels was compared with that of contrast-enhanced EUS. This article describes the DFI technique along with our first experience of its use for vascular assessment of pancreatobiliary lesions. Vessels were imaged in 34 pancreatic solid lesions, eight intraductal papillary mucinous neoplasms (IPMNs), seven gall bladder lesions, and four swollen lymph nodes. DFI-EUS (91%) was significantly superior to e-FLOW EUS (53%) with respect to detection of vessels (p < 0.001) and for discrimination of mural nodules from mucous clots in IPMN and gallbladder lesions from sludge (p = 0.046). Thus, DFI-EUS has the potential to become an essential tool for diagnosis and vascular assessment of various diseases.
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Cakir, B. O., S. Lavagnoli, B. H. Saracoglu, and C. Fureby. "Optical Flow Based Background Oriented Schlieren for Compressible Flows." Proceedings of the International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics 20 (July 11, 2022): 1–17. http://dx.doi.org/10.55037/lxlaser.20th.6.
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Optical flow provides an opportunity to e levate the resolution and s ensitivity of deflection se nsing in background oriented schlieren (BOS). Despite extensive relevant literature within the field of computer v ision, with regards to BOS, there is a lack of proper quantification of its abilities and l imitations. Thus, this study performs a comparative assessment characterizing accuracy and resolution limits in different flow field scenarios utilizing background patterns generated with speckle and wavelet noise distributions. Accordingly, a synthetic assessment over direct numerical simulations of a buoyancy driven turbulence is performed with variations introduced in the background patterns and operational parameters of optical flow where a c lear s uperiority o f a ccuracy a nd r esolvable r ange o f density gradient amplitudes over cross-correlation is demonstrated. Moreover, an experimental assessment of supersonic flow features over multiple models is conducted to characterize the influence of experimental considerations related to the application of optical flow in BOS and its comparative performance against the block-matching counterpart.
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Islam, Md Tasbirul, and Nazmul Huda. "Application of Material Flow Analysis (MFA) in Electronic Waste (E-Waste) Management: A Review." Proceedings 2, no. 23 (November 6, 2018): 1457. http://dx.doi.org/10.3390/proceedings2231457.
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This paper reviews around 41 articles providing the trends, characteristics, research gaps and challenges of these studies that may help e-waste management-related academics and practitioners with an overview of the need for such tool to be applied. The results and highlighted future research perspectives discussed in this study will definitely help to analyze e-waste management systems with more critical aspects, i.e., hidden and known flows of waste products and associated materials, economic assessment of material recovery and the role of responsible authorities.
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Kenderova, Rossitza, and Georgi Rachev. "Characteristic of debris flow in the Kresna gorge on September 26, 2020." Review of the Bulgarian Geological Society 82, no. 3 (December 2021): 182–84. http://dx.doi.org/10.52215/rev.bgs.2021.82.3.180.
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On September 26, 2021 a sudden debris flow in the northern part of the Kresna Gorge suspended traffic on the international road E-79. The following paper characterizes the synoptic situation that leads to a debris flow event and related deposits. The type of flow is determined bases on data obtained from grain size and morphoscopic analyses. A general assessment of the strengthening measures is made.
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Ismail, Haikal, and Marlia M. Hanafiah. "Evaluation of e-waste management systems in Malaysia using life cycle assessment and material flow analysis." Journal of Cleaner Production 308 (July 2021): 127358. http://dx.doi.org/10.1016/j.jclepro.2021.127358.
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Withanage, Sohani Vihanga, and Komal Habib. "Life Cycle Assessment and Material Flow Analysis: Two Under-Utilized Tools for Informing E-Waste Management." Sustainability 13, no. 14 (July 16, 2021): 7939. http://dx.doi.org/10.3390/su13147939.
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The unprecedented technological development and economic growth over the past two decades has resulted in streams of rapidly growing electronic waste (e-waste) around the world. As the potential source of secondary raw materials including precious and critical materials, e-waste has recently gained significant attention across the board, ranging from governments and industry, to academia and civil society organizations. This paper aims to provide a comprehensive review of the last decade of e-waste literature followed by an in-depth analysis of the application of material flow analysis (MFA) and life cycle assessment (LCA), i.e., two less commonly used strategic tools to guide the relevant stakeholders in efficient management of e-waste. Through a keyword search on two main online search databases, Scopus and Web of Science, 1835 peer-reviewed publications were selected and subjected to a bibliographic network analysis to identify and visualize major research themes across the selected literature. The selected 1835 studies were classified into ten different categories based on research area, such as environmental and human health impacts, recycling and recovery technologies, associated social aspects, etc. With this selected literature in mind, the review process revealed the two least explored research areas over the past decade: MFA and LCA with 33 and 31 studies, respectively. A further in-depth analysis was conducted for these two areas regarding their application to various systems with numerous scopes and different stages of e-waste life cycle. The study provides a detailed discussion regarding their applicability, and highlights challenges and opportunities for further research.
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Markl, M. "WE-E-210A-01: Functional Cardiovascular MRI: Assessment, Visualization and Quantification of 3D Blood Flow Characteristics." Medical Physics 36, no. 6Part26 (June 2009): 2787. http://dx.doi.org/10.1118/1.3182578.
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Holt, Robert W., Edward Meiman, and Thomas L. Seamster. "Evaluation of Aircraft Pilot Team Performance." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 40, no. 2 (October 1996): 44–48. http://dx.doi.org/10.1177/154193129604000208.
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Accurate assessment of team performance in complex, dynamic systems is difficult, particularly teamwork such as Crew Resource Management (CRM) in aircraft. Seventy pilots from two fleets were evaluated as two-person crews by a Maneuver Validation (MV), which focused on proficiency on separate maneuvers, and by a Line Operational Evaluation (LOE), which focused on the crew flying a simulated line flight. Instructor/Evaluator (I/E) pilots helped design LOE content and a structured evaluation worksheet. I/E reliability training resulted in high evaluator agreement (average rwg = .80) and acceptable inter-rater correlations (average r = .54). Path analysis supported the assessment flow from Observable Behaviors to Technical and CRM performance to Captain (PIC), First Officer (SIC), and Crew evaluations for each event set. Fleet evaluations were different on the LOE assessment, but equivalent on the MV assessment. Detailed analysis of assessments also indicated a different role of the SIC across fleets. One fleet assessed SIC more on CRM performance and weighted SIC performance more in evaluating Crew performance. The other fleet assessed SIC on technical performance and weighted SIC performance less in evaluating Crew performance.
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Ma, Lejun, Huan Wang, Changjun Qi, Xinnan Zhang, and Hanwen Zhang. "Characteristics and Adaptability Assessment of Commonly Used Ecological Flow Methods in Water Storage and Hydropower Projects, the Case of Chinese River Basins." Water 11, no. 10 (September 29, 2019): 2035. http://dx.doi.org/10.3390/w11102035.
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The construction and operation of water storage and hydropower projects affects the structure of water ecosystems of downstream rivers, and the establishment of ecological flow in rivers below the water storage and hydropower projects has significant impacts on maintaining the stability of river ecosystems. A database was established based on 2000–2017 environmental impact assessment (EIA) reports on water storage and hydropower projects in China and ecological flow (e-flow) methods, and the three widely used e-flow methods for water storage and hydropower projects in China were identified on the database. Furthermore, an ecological flow satisfaction degree model was used to evaluate the methods using long series of historical hydrological data from the hydrological stations in the Yellow River basin, the Yangtze River basin, and the Liao River basin. The results showed that hydrological methods are the type most often used for water storage and hydropower projects in China, including the Tennant method, the minimum monthly average flow with 90% guarantee rate method (Mm9M method), and the measured historical minimum daily average flow rate method (MDM method). However, the ecological flow methods selected are not significantly different among different basins, indicating that the selection of ecological flow methods is rather arbitrary, and adaptability analysis is not available. The results of the ecological flow satisfaction model showed that the Tennant method is not suitable for large river basins. The results of this study can provide technical support for establishment and management decisions surrounding ecological flow.
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R. A. Indrawati. "E-Learning in Indonesia." Journal of Indonesian Scholars for Social Research 2, no. 2 (July 29, 2022): 91–97. http://dx.doi.org/10.59065/jissr.v2i2.34.
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As part of this research, students rated the e-learning module on the LMS. We give substantial qualitative interview data. General satisfaction and disapproval questions indicate student assessment criteria, whereas module-specific questions reveal student learning processes. Lesson topics, discussion forums, student interactions, and other learning tools are utilized by students to show pleasure. Topics of discontent include platform robustness and usability, study materials (articles and books), and student workloads. The flow of debate and engagement is appreciated, but students are worried about participating, and expectations regarding the role of lecturers in e-learning haven't been developed.
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Derepasko, Diana, Francisco J. Peñas, José Barquín, and Martin Volk. "Applying Optimization to Support Adaptive Water Management of Rivers." Water 13, no. 9 (April 30, 2021): 1281. http://dx.doi.org/10.3390/w13091281.
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Adaptive water management is a promising management paradigm for rivers that addresses the uncertainty of decision consequences. However, its implementation into current practice is still a challenge. An optimization assessment can be framed within the adaptive management cycle allowing the definition of environmental flows (e-flows) in a suitable format for decision making. In this study, we demonstrate its suitability to mediate the incorporation of e-flows into diversion management planning, fostering the realization of an adaptive management approach. We used the case study of the Pas River, Northern Spain, as the setting for the optimization of surface water diversion. We considered e-flow requirements for three key river biological groups to reflect conditions that promote ecological conservation. By drawing from hydrological scenarios (i.e., dry, normal, and wet), our assessment showed that the overall target water demand can be met, whereas the daily volume of water available for diversion was not constant throughout the year. These results suggest that current the decision making needs to consider the seasonal time frame as the reference temporal scale for objectives adjustment and monitoring. The approach can be transferred to other study areas and can inform decision makers that aim to engage with all the stages of the adaptive water management cycle.
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De Hert, Stefan G., Philippe J. Vander Linden, Pieter W. ten Broecke, Peter A. De Mulder, Inez E. Rodrigus, and Hugo F. Adriaensen. "Assessment of Length-dependent Regulation of Myocardial Function in Coronary Surgery Patients Using Transmitral Flow Velocity Patterns." Anesthesiology 93, no. 2 (August 1, 2000): 374–81. http://dx.doi.org/10.1097/00000542-200008000-00015.
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Background In a subset of coronary surgery patients, a transient increase in cardiac load by leg elevation resulted in a decrease in maximal rate of pressure development (dP/dtmax) and a major increase in end-diastolic pressure (EDP). This impairment of left ventricular (LV) function appeared to be related to a deficient length-dependent regulation of myocardial function. The present study investigated whether analysis of transmitral flow patterns with transesophageal echocardiography constituted a noninvasive method to identify these patients. Methods High-fidelity LV pressure tracings and transmitral flow signals were obtained in 50 coronary surgery patients during an increase in cardiac load by leg elevation. Using linear regression analysis, changes in transmitral E-wave velocity and deceleration time (DT) were related to changes in dP/dtmax and EDP. Results Changes in dP/dtmax with leg elevation were closely related to corresponding changes in E-wave velocity (r = 0.81; P < 0. 001) and to changes in DT (r = 0.78; P < 0.001). Similarly, changes in EDP were related to changes in E-wave velocity (r = 0.83; P < 0. 001) and to changes in DT (r = 0.84; P < 0.001). The decrease in dP/dtmax and the major increase in EDP in some patients was associated with an increase in E-wave velocity and a decrease in DT, indicating development of a restrictive LV filling pattern. Conclusions Impairment of LV function with leg elevation was associated with the development of a restrictive transmitral filling pattern. Analysis of transmitral flow patterns by means of transesophageal echocardiography therefore allowed noninvasive identification of a subset of coronary surgery patients with impaired length-dependent regulation of LV function.
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Jepras, R. I., F. E. Paul, S. C. Pearson, and M. J. Wilkinson. "Rapid assessment of antibiotic effects on Escherichia coli by bis-(1,3-dibutylbarbituric acid) trimethine oxonol and flow cytometry." Antimicrobial Agents and Chemotherapy 41, no. 9 (September 1997): 2001–5. http://dx.doi.org/10.1128/aac.41.9.2001.
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The effects of selected antibiotics on Escherichia coli were studied by flow cytometry with the fluorescent anionic membrane potential probe bis-(1,3-dibutylbarbituric acid) trimethine oxonol [DiBAC4(3)]. The actions of azithromycin, cefuroxime, and ciprofloxacin at five times the MIC on E. coli were compared by the traditional CFU assay and flow cytometry. Changes in viable counts of bacteria determined with DiBAC4(3) and by flow cytometry following treatment with the antibiotics showed trends similar to those found by the CFU assays. However, viable counts determined by flow cytometry following antibiotic treatment were 1 to 2 logs higher than those determined by the corresponding CFU assays. All the results obtained by flow cytometry were provided within 10 min after sampling, whereas the conventional CFU assay results took at least 18 h. The results indicated that flow cytometry is a sensitive analytical technique that can rapidly monitor the physiological changes of individual microorganisms following antibiotic action and can provide information on the mode of action of a drug. The membrane potential probe DiBAC4(3) provides a robust flow cytometric indicator for bacterial cell viability.
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Espinoza, T., M. Connell, S. Marshall, R. Beukeboom, and A. McDougall. "Nesting behaviour of the endangered Mary River turtle: monitoring and modelling to inform e-flow strategies." Australian Journal of Zoology 66, no. 1 (2018): 15. http://dx.doi.org/10.1071/zo17044.
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The Mary River turtle (Elusor macrurus) is an endemic, monotypic species with multiple impacts across its life-history, including overharvesting of eggs, nest predation and habitat degradation. Long-term recruitment failure has led to protection measures established under state, federal and international authority. Previous research has demonstrated that E. macrurus lives instream but nests on river banks, requiring specific habitat for breeding, nesting and recruitment. Ecohydrological rules represent the critical water requirements contributing to a species’ life history and can be used to develop and assess environmental flow strategies for species affected by water resource development. This study investigated the nesting behaviour of E. macrurus, including the environmental drivers that affect nest inundation. Monitoring showed that nesting by E. macrurus peaked in October and November, driven by rainfall events (>10 mm), with potential impacts from flow events (20% of nests established <2.5 m above water level at time of nesting). These ecohydrological rules were modelled against 109 years of simulated natural flow and rainfall data. The ‘potential nesting and nest inundation’ (PNNI) indicator revealed that nesting for E. macrurus was assured in a majority of years under the natural flow scenario. The results of this study will inform the development and assessment of e-flow strategies for nesting by E. macrurus in terms of current, and future water resource development, along with climate change impacts.
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Hees, Paul S., Jerome L. Fleg, Sheng-Jing Dong, and Edward P. Shapiro. "MRI and echocardiographic assessment of the diastolic dysfunction of normal aging: altered LV pressure decline or load?" American Journal of Physiology-Heart and Circulatory Physiology 286, no. 2 (February 2004): H782—H788. http://dx.doi.org/10.1152/ajpheart.01092.2002.
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Changes in diastolic indexes during normal aging, including reduced early filling velocity ( E), lengthened E deceleration time (DT), augmented late filling ( A), and prolonged isovolumic relaxation time (IVRT), have been attributed to slower left ventricular (LV) pressure (LVP) decay. Indeed, this constellation of findings is often referred to as the “abnormal relaxation” pattern. However, LV filling is determined by the atrioventricular pressure gradient, which depends on both LVP decline and left atrial (LA) pressure (LAP). To assess the relative influence of LVP decline and LAP, we studied 122 normal subjects aged 21–92 yr by Doppler echocardiography and MRI. LVP decline was assessed by color M-mode ( Vp) and the LV untwisting rate. Early diastolic LAP was evaluated using pulmonary vein flow systolic fraction, pulmonary vein flow diastolic DT, color M-mode ( E/ Vp), and tissue Doppler ( E/ Em). Linear regression showed the expected reduction of E, increase in A, and prolongation of IVRT and DT with advancing age. There was no relation of age to parameters reflecting the rate of LVP decline. However, older age was associated with reduced E/ Vp ( P = 0.008) and increased pulmonary vein systolic fraction ( P < 0.001), pulmonary vein DT ( P = 0.0026), and E/ Em ( P < 0.0001), all suggesting reduced early LAP. Therefore, reduced early filling in older adults may be more closely related to a reduced early diastolic LAP than to slower LVP decline. This effect also explains the prolonged IVRT. We postulate that changes in LA active or passive properties may contribute to development of the abnormal relaxation pattern during the aging process.
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Amirbekian, Smbat, Robert C. Long, Michelle A. Consolini, Jin Suo, Nick J. Willett, Sam W. Fielden, Don P. Giddens, W. Robert Taylor, and John N. Oshinski. "In vivo assessment of blood flow patterns in abdominal aorta of mice with MRI: implications for AAA localization." American Journal of Physiology-Heart and Circulatory Physiology 297, no. 4 (October 2009): H1290—H1295. http://dx.doi.org/10.1152/ajpheart.00889.2008.
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Abdominal aortic aneurysms (AAA) localize in the infrarenal aorta in humans, while they are found in the suprarenal aorta in mouse models. It has been shown previously that humans experience a reversal of flow during early diastole in the infrarenal aorta during each cardiac cycle. This flow reversal causes oscillatory wall shear stress (OWSS) to be present in the infrarenal aorta of humans. OWSS has been linked to a variety of proatherogenic and proinflammatory factors. The presence of reverse flow in the mouse aorta is unknown. In this study we investigated blood flow in mice, using phase-contrast magnetic resonance (PCMR) imaging. We measured blood flow in the suprarenal and infrarenal abdominal aorta of 18 wild-type C57BL/6J mice and 15 apolipoprotein E (apoE)−/− mice. Although OWSS was not directly evaluated, results indicate that, unlike humans, there is no reversal of flow in the infrarenal aorta of wild-type or apoE−/− mice. Distensibility of the mouse aortic wall in both the suprarenal and infrarenal segments is higher than reported values for the human aorta. We conclude that normal mice do not experience the reverse flow in the infrarenal aorta that is observed in humans.
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Wu, Yue, and Sándor J. Kovács. "Frequency-based analysis of the early rapid filling pressure-flow relation elucidates diastolic efficiency mechanisms." American Journal of Physiology-Heart and Circulatory Physiology 291, no. 6 (December 2006): H2942—H2949. http://dx.doi.org/10.1152/ajpheart.00259.2006.
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Stiffness- and relaxation-based diastolic function (DF) assessment can characterize the presence, severity, and mechanism of dysfunction. Although frequency-based characterization of arterial function is routine (input impedance, characteristic impedance, arterial wave reflection), DF assessment via frequency-based methods incorporating optimization/efficiency criteria is lacking. By definition, optimal filling maximizes (E wave) volume and minimizes “loss” at constant stored elastic strain energy (which initiates mechanical, recoil-driven filling). In thermodynamic terms, optimal filling delivers all oscillatory power (rate of work) at the lowest harmonic. To assess early rapid filling optimization, simultaneous micromanometric left ventricular pressure and echocardiographic transmitral flow (Doppler E wave) were Fourier analyzed in 31 subjects. A validated kinematic filling model provided closed-form expressions for E wave contours and model parameters. Relaxation-based DF impairment is indicated by prolonged E wave deceleration time (DT). Optimization was assessed via regression between the dimensionless ratio of 2nd (Q2) and 3rd flow harmonics (Q3) to the lowest harmonic (Q1), i.e., (Q2/Q1) or (Q3/Q1) vs. DT or c, the filling model’s viscosity/damping (energy loss) parameter. Results show that DT prolongation or increased c generated increased oscillatory power at higher harmonics (Q2/Q1 = 0.00091DT + 0.09837, r = 0.70; Q3/Q1 = 0.00053DT + 0.02747, r = 0.60; Q2/Q1 = 0.00614 c + 0.15527, r = 0.91; Q3/Q1 = 0.00396 c + 0.05373, r = 0.87). Because ideal filling is achieved when all oscillatory power is delivered at the lowest harmonic, the observed increase in power at higher harmonics is a measure of filling inefficiency. We conclude that frequency-based analysis facilitates assessment of filling efficiency and elucidates the mechanism by which diastolic dysfunction associated with prolonged DT impairs optimal filling.
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Rezaeinejad, Saeid, and Volodymyr Ivanov. "Assessment of correlation between physiological states of Escherichia coli cells and their susceptibility to chlorine using flow cytometry." Water Supply 13, no. 4 (August 1, 2013): 1056–62. http://dx.doi.org/10.2166/ws.2013.083.
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The physiological differences of individual cells of bacterial population may imply the existence of cell subpopulations with different sensitivity to chlorine, which may affect the efficiency of drinking water disinfection. The susceptibility of individual bacterial cells to chlorine was examined using flow cytometry. The inactivation of Escherichia coli cells by chlorine in the populations with specific growth rates of 0.2 and 0.9 h−1 was assessed using various viability indicators. Viability of bacterial cells was evaluated using membrane integrity propidium iodide (PI) dye, respiratory activity indicator of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) and membrane potential probe of DiBAC4(3). It was found that there were cell subpopulations of E. coli with different levels of susceptibility to chlorine. E. coli cell population with higher specific growth rate was more susceptible to chlorine. The CT values for inactivation of 99% of cells (CT99) in populations of E. coli with specific growth rates of 0.9 and 0.2 h−1 were 0.06 and 0.09 mg min l−1, respectively. Flow cytometry could be used to study the sensitivity of bacterial cells to the chemical agents.
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Rijal, Narayanhari, Hari Krishna Shrestha, and Bert Bruins. "Environmental Flow Assessment of Hewa Khola A and Lower Hewa Khola Hydropower Projects in Nepal." Hydro Nepal: Journal of Water, Energy and Environment 23 (August 21, 2018): 71–78. http://dx.doi.org/10.3126/hn.v23i0.20828.
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One of the elements of sustainable hydropower development is the release of the environmental flows (Eflows). This Eflows is meant to ensure that prior use(r)s of the river water are respected and that essential riverine ecosystem functions are maintained. This paper presents the results of an e-flows assessment, using the hydrological index method, of Hewa Khola A and Lower Hewa Khola Hydropower Projects, in Phidim, Nepal. These projects are being developed in the tributaries of Tamor River in Eastern part of Nepal. The e-flows assessment results are compared with the current releases made from the projects in operation. Current operations are prone to lead to severe degradation and social conflict. Based on an evaluation of the effects of a higher Eflows release on the power production, the paper concludes with recommendations for appropriate Eflow releases, and thus for socially and environmentally sustainable operations of the hydropower projects. HYDRO Nepal JournalJournal of Water, Energy and Environment Issue: 23Year: 2018
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De Villiers, Cecilia, Sabine Ettinger, and Judit Erdos. "OP112 Project Management for EUnetHTA Non-Pharmaceutical Technologies." International Journal of Technology Assessment in Health Care 35, S1 (2019): 27. http://dx.doi.org/10.1017/s0266462319001533.
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IntroductionThe European Network for Health Technology Assessment (EUnetHTA) facilitates and produces Health Technology Assessments (HTA) across Europe. Project Management (PM) provides the coordination and strategic overview of assessment production and enables the flow of scientific knowledge and assessment publications through collaboration and standardized processes, procedures and documentation.MethodsEUnetHTA established a central PM function at the Ludwig Boltzmann Institute for HTA (LBI-HTA) for central coordination and assessment production of non-pharmaceutical technologies. LBI-HTA subsequently pursued capability and capacity through a decentralized hub-and-spoke-PM model with six activity centers (AC) providing decentralized coordination and PM of assessments. LBI-HTA provided central oversight and supervision with training days, e-meetings and ad hoc e-mail and telephone support as required. This was complemented by standardized operating procedures (SOPs) in the online Companion Guide (CG). A qualitative data collection via electronic questionnaires collected feedback from AC-PM, LBI-HTA-PM and assessment authors. Specific questions with free-text responses assessed current experiences, challenges, recommendations, communication and task distributions of the centralized and decentralized PM processes from these different perspectives.ResultsThe feedback concluded that PM is a separate, well-defined and important role for assessment coordination and production. The AC-PM received adequate training from the central PM and authors experienced no difference between projects managed centrally or decentrally. The CG and SOPs are important for guiding standard practice and allowing AC-PM to operate independently. Challenges were around extended timelines due to complex topics, external stakeholder involvement, insufficient team communication and not yet published SOPs resulting in additional central support.ConclusionsDecentralized coordination of assessments, knowledge management and governance achieve scale, capacity and capability through a designated pool of agencies with established roles and growing experience in sustainable collaboration of HTA production. Valuable insight into the PM model's operational efficiency, avoidance of duplication and resource savings potentially provides a sustainable post 2020 European network policy and efficiency model for high quality HTA assessment production.
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Franco, Pamela, Julio Sotelo, Cristian Montalba, Bram Ruijsink, Eric Kerfoot, David Nordsletten, Joaquín Mura, Daniel Hurtado, and Sergio Uribe. "Comprehensive Assessment of Left Intraventricular Hemodynamics Using a Finite Element Method: An Application to Dilated Cardiomyopathy Patients." Applied Sciences 11, no. 23 (November 25, 2021): 11165. http://dx.doi.org/10.3390/app112311165.
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In this paper, we applied a method for quantifying several left intraventricular hemodynamic parameters from 4D Flow data and its application in a proof-of-concept study in dilated cardiomyopathy (DCM) patients. In total, 12 healthy volunteers and 13 DCM patients under treatment underwent short-axis cine b-SSFP and 4D Flow MRI. Following 3D segmentation of the left ventricular (LV) cavity and registration of both sequences, several hemodynamic parameters were calculated at peak systole, e-wave, and end-diastole using a finite element approach. Sensitivity, inter- and intra-observer reproducibility of hemodynamic parameters were evaluated by analyzing LV segmentation. A local analysis was performed by dividing the LV cavity into 16 regions. We found significant differences between volunteers and patients in velocity, vorticity, viscous dissipation, energy loss, and kinetic energy at peak systole and e-wave. Furthermore, although five patients showed a recovered ejection fraction after treatment, their hemodynamic parameters remained low. We obtained several hemodynamic parameters with high inter- and intra-observer reproducibility. The sensitivity study revealed that hemodynamic parameters showed a higher accuracy when the segmentation underestimates the LV volumes. Our approach was able to identify abnormal flow patterns in DCM patients compared to volunteers and can be applied to any other cardiovascular diseases.
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Pereira, Donizete dos R., Mauro A. Martinez, André Q. de Almeida, Fernando F. Pruski, Demetrius D. da Silva, and João H. Zonta. "Hydrological simulation using SWAT model in headwater basin in Southeast Brazil." Engenharia Agrícola 34, no. 4 (August 2014): 789–99. http://dx.doi.org/10.1590/s0100-69162014000400018.
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Hydrological models are important tools that have been used in water resource planning and management. Thus, the aim of this work was to calibrate and validate in a daily time scale, the SWAT model (Soil and Water Assessment Tool) to the watershed of the Galo creek , located in Espírito Santo State. To conduct the study we used georeferenced maps of relief, soil type and use, in addition to historical daily time series of basin climate and flow. In modeling were used time series corresponding to the periods Jan 1, 1995 to Dec 31, 2000 and Jan 1, 2001 to Dec 20, 2003 for calibration and validation, respectively. Model performance evaluation was done using the Nash-Sutcliffe coefficient (E NS) and the percentage of bias (P BIAS). SWAT evaluation was also done in the simulation of the following hydrological variables: maximum and minimum annual daily flowsand minimum reference flows, Q90 and Q95, based on mean absolute error. E NS and P BIAS were, respectively, 0.65 and 7.2% and 0.70 and 14.1%, for calibration and validation, indicating a satisfactory performance for the model. SWAT adequately simulated minimum annual daily flow and the reference flows, Q90 and Q95; it was not suitable in the simulation of maximum annual daily flows.
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Nazarenko, M. Y., and A. B. Zolotukhin. "FAILURE TO ACHIEVE PLANNED ECONOMIC PERFORMANCE OF OIL AND GAS PRODUCTION PROJECTS DUE TO LACK OF RISK ASSESSMENT AND UNCERTAINTY QUANTIFICATION." Энергия: экономика, техника, экология, no. 3 (2020): 75–80. http://dx.doi.org/10.7868/s2587739920030118.
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Quantitative assessment of risks and uncertainty has always played the most important role in the evaluation of oil & gas projects. Any estimated, measurable or evaluable magnitude contains an uncertainty, whether it concerns measuring watercut by means of a multiphase flow meter (MPFM) or to the net present value (NPV) of a major E&P project. Evaluation of project economics, e.g. the calculation of net present value (NPV), internal rate of return (IRR), OPEX and CAPEX shall be probabilistic, i.e. carried out with the quantitative assessment of risks and uncertainty of estimated (predicted) values. Nevertheless probabilistic estimate takes place very rarely. Most commonly, assessment of risks and uncertainty would be intuitive or based on a number of deterministic scenarios mistakenly referred to as pessimistic, optimistic and most probable. This research simulates failure to achieve target economic efficiency of E&P projects with no quantitative assessment of risks and uncertainty, and reviews previous international research conducted to identify the effect of ignoring probabilistic estimates related to the evaluation of E&P projects on their final economic efficiency.
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Altantzis, Angelos-Ikaros, Nikolaos-Christos Kallistridis, George Stavropoulos, and Anastasia Zabaniotou. "Apparent Pyrolysis Kinetics and Index-Based Assessment of Pretreated Peach Seeds." Processes 9, no. 6 (May 21, 2021): 905. http://dx.doi.org/10.3390/pr9060905.
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To better understand pyrolysis for upscaling purposes, a kinetic characterization of the process is necessary for every feedstock. Laboratory experiments allow identification of apparent kinetic models. This paper aims at the apparent kinetic investigation of peach seeds’ slow pyrolysis. Peach seeds from Greek peach fruits pyrolyzed under inert atmospheric conditions at different temperatures (475–785 °C), heating rates (100–250 °C/min) and N2 flow rates (25–200 cc/min). Prior to pyrolysis, they submitted to hexane extraction for the recovery of 36.8% wt. of the contained oils. Determination of the specific rate constant (k) and activation energy (Ea) for each considered reaction was made by using the Coats–Redfern integral non-isothermal fitting model that requires an assumption of the reaction order (n). Results revealed that a 3rd order reaction model best fits the process, the increasing of the pyrolysis temperature leads to a decrease of the activation energy (E) and pre-exponential factor (A), while nitrogen flow rate and heating rate had an opposite impact. E and A values ranged from 23 to 56 kJ/mol and 1.82 × 106 to 1.13 × 106 min−1, respectively, at different pyrolysis conditions. Furthermore, estimation of combustion and pyrolysis indexes were made to assess the suitability of peach seeds as a fuel, using isothermal thermogravimetric analyses (TGA). Results revealed that peach seeds are a suitable feedstock for pyrolysis, while prior submission of peach seeds to oils extraction, in a cascade biorefinery approach, can increase the energy and material recovery efficiency and potentially the environmental and economic benefit of the agri-food industrial sector.
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Lemons, Ansley, Ariel Branz, Mesiaki Kimirei, Tracy Hawkins, and Daniele Lantagne. "Assessment of the quality, effectiveness, and acceptability of ceramic water filters in Tanzania." Journal of Water, Sanitation and Hygiene for Development 6, no. 2 (May 10, 2016): 195–204. http://dx.doi.org/10.2166/washdev.2016.006.
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Globally, approximately two billion people drink contaminated water. Use of household water treatment (HWT) methods, such as locally manufactured ceramic filters, reduces the diarrheal disease burden associated with unclean water. We evaluated the quality, effectiveness, and acceptability of ceramic filters in two communities in Arusha, Tanzania, by conducting: 1) baseline household surveys with 50 families; 2) filter flow rate testing; 3) filter distribution with training sessions; 4) follow-up surveys at 2, 4, and 6 weeks after distribution; and 5) project end focus group discussions. We tested Escherichia coli (E. coli) and turbidity at baseline and the first two follow-ups. We found: 1) filter quality was low, as only 46% of filters met recommended flow rate guidelines and 18% of filters broke during the 6-week study; 2) filter effectiveness was moderate, with 8% and 35% of filters effectively reducing E. coli to <1 CFU/100 mL and <10 CFU/100 mL, respectively, at follow-ups; and, 3) filter acceptability was high, with 94% overall satisfaction and 96–100% reported use in the previous day. These results highlight the importance of mixed methods research as HWT product quality, effectiveness, and acceptability all impact product efficacy, and the need for quality assurance/quality control and certification schemes for locally manufactured HWT products.
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Caiati, Carlo, Paolo Desario, Giuseppe Tricarico, Fortunato Iacovelli, Paolo Pollice, Stefano Favale, and Mario Erminio Lepera. "Wellens’ Syndrome from COVID-19 Infection Assessed by Enhanced Transthoracic Coronary Echo Doppler: A Case Report." Diagnostics 12, no. 4 (March 25, 2022): 804. http://dx.doi.org/10.3390/diagnostics12040804.
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Wellens’ syndrome (WS) is a preinfarction state caused by a sub-occlusion of the proximal left anterior descending coronary artery (LAD). In this case report, for the first time, we describe how this syndrome can be caused by COVID-19 infection and, most importantly, that it can be assessed bedside by enhanced transthoracic coronary echo Doppler (E-Doppler TTE). This seasoned technique allows blood flow Doppler to be recorded in the coronaries and at the stenosis site but has never been tested in an acute setting. Two weeks after clinical recovery from bronchitis allegedly caused by COVID-19 infection on the basis of epidemiologic criteria (no swab performed during the acute phase but only during recovery, at which time it was negative), our patient developed typical angina for the first time, mainly during effort but also at rest. He was admitted to our tertiary center, where pharyngeal swabs tested positive for COVID-19. A typical EKG finding supporting WS prompted an assessment of the left main coronary artery (LMCA) and the whole LAD blood flow velocity by E-Doppler TTE. Localized high velocity (transtenotic velocity) (100 cm/s) was recorded in the proximal LAD, with the reference velocity being 20 cm/s. This indicated severe stenosis with 90% area narrowing according to the continuity equation, as confirmed by coronary angiography. During follow-up after successful stenting, E-Doppler TTE showed a decrease in the transtenotic acceleration, confirming stent patency and a normal coronary flow reserve (3.2) and illustrating a normal microcirculatory function. Conclusion: COVID infection can trigger a coronary syndrome like WS. E-Doppler TTE, an ionizing radiation-free method, allows safe and rapid bedside management of the syndrome. This new strategy can be pivotal in distinguishing true WS from pseudo-WS. In cases of pseudo-WS, coronary angiography can be avoided. If E-Doppler TTE confirms the stenosis and PCI (percutaneous coronary intervention) is performed, the same method can allow assessment over time of the precise residual stenosis after stenting and verify the microvasculature status by evaluating coronary flow reserve.
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Nicosia, Alessio, Vincenzo Pampalone, and Vito Ferro. "Effects of Biochar Addition on Rill Flow Resistance." Water 13, no. 21 (October 29, 2021): 3036. http://dx.doi.org/10.3390/w13213036.
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The development of rills on a hillslope whose soil is amended by biochar remains a topic to be developed. A theoretical rill flow resistance equation, obtained by the integration of a power velocity distribution, was assessed using available measurements at plot scale with a biochar added soil. The biochar was incorporated and mixed with the arable soil using a biochar content BC of 6 and 12 kg m−2. The developed analysis demonstrated that an accurate estimate of the velocity profile parameter Гv can be obtained by the proposed power equation using an exponent e of the Reynolds number which decreases for increasing BC values. This result pointed out that the increase of biochar content dumps flow turbulence. The agreement between the measured friction factor values and those calculated by the proposed flow resistance equation, with Гv values estimated by the power equation calibrated on the available measurements, is characterized by errors which are always less than or equal to ±10% and less than or equal to ±3% for 75.0% of cases. In conclusion, the available measurements and the developed analysis allowed for (i) the calibration of the relationship between Гv, the bed slope, the flow Froude number, and the Reynolds number, (ii) the assessment of the influence of biochar content on flow resistance and, (iii) stating that the theoretical flow resistance equation gives an accurate estimate of the Darcy–Weisbach friction factor for rill flows on biochar added soils.
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Lisauskas, Jennifer B., Jasvindar Singh, Andrew W. Bowman, and Sándor J. Kovács. "Chamber properties from transmitral flow: prediction of average and passive left ventricular diastolic stiffness." Journal of Applied Physiology 91, no. 1 (July 1, 2001): 154–62. http://dx.doi.org/10.1152/jappl.2001.91.1.154.
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A chamber stiffness ( KLV)-transmitral flow (E-wave) deceleration time relation has been invasively validated in dogs with the use of average stiffness [(ΔP/ΔV)avg]. KLVis equivalent to kE, the (E-wave) stiffness of the parameterized diastolic filling model. Prediction and validation of 1) (ΔP/ΔV)avgin terms of kE, 2) early rapid-filling stiffness [(ΔP/ΔV)E] in terms of kE, and 3) passive (postdiastasis) chamber stiffness [(ΔP/ΔV)PD] from A waves in terms of the stiffness parameter for the Doppler A wave ( kA) have not been achieved. Simultaneous micromanometric left ventricular (LV) pressure (LVP) and transmitral flow from 131 subjects were analyzed. (ΔP)avgand (ΔV)avgutilized the minimum LVP-LV end-diastolic pressure interval. (ΔP/ΔV)Eutilized ΔP and ΔV from minimum LVP to E-wave termination. (ΔP/ΔV)PDutilized atrial systolic ΔP and ΔV. E- and A-wave analysis generated kEand kA. For all subjects, noninvasive-invasive relations yielded the following equations: kE= 1,401 · (ΔP/ΔV)avg+ 59.2 ( r = 0.84) and kE= 229.0 · (ΔP/ΔV)E+ 112 ( r= 0.80). For subjects with diastasis ( n = 113), kA= 1,640 · (ΔP/ΔV)PD− 8.40 ( r = 0.89). As predicted, kAshowed excellent correlation with (ΔP/ΔV)PD; kEcorrelated highly with (ΔP/ΔV)avg. In vivo validation of average, early, and passive chamber stiffness facilitates quantitative, noninvasive diastolic function assessment from transmitral flow.
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Souza, Kaíse Barbosa, João Batista Lopes Silva, Rafael Felippe Ratke, Gerson Santos Lisboa, and Karla Nayara Santos Almeida. "INFLUÊNCIA DO USO E OCUPAÇÃO DO SOLO NA DISPONIBILIDADE HÍDRICA DA BACIA HIDROGRÁFICA DO RIO URUÇUÍ-PRETO, PIAUÍ." Nativa 7, no. 5 (September 12, 2019): 567. http://dx.doi.org/10.31413/nativa.v7i5.7181.
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Objetivou-se verificar a influência das mudanças no uso e ocupação do solo na disponibilidade hídrica da bacia hidrográfica do rio Uruçuí-Preto, Piauí, no período de 1984 a 2007. Para a avaliação do uso do solo foram utilizadas imagens do Satélite Landsat 5, sensor TM (Thematic Mapper) e realizou-se a classificação automática supervisionada auxiliada pelo algoritmo de Máxima Verossimilhança. Para a análise do comportamento hidrológico foram utilizados dados da vazão média, máxima e mínima anual; vazão mínima com sete dias de duração anual (Q7); e as vazões associadas às permanências de 90% (Q90) e 95% (Q95). Para a associação entre as vazões e o uso do solo, fez-se a correlação simples entre as variáveis, testando seu nível de significância a 5% (p < 0,05) de probabilidade. Os resultados demonstraram que ao comparar os anos de 1984 e 2007, as classes Cerrado e Mata Ciliar reduziram 20,9% e 2,4% respectivamente, a classe Solo Exposto/Talhão Agrícola aumentou 13,48% e a classe Queimada aumentou 9,83%. Não ocorreram correlações significativas entre as variáveis classes de mudanças no uso e ocupação do solo e as vazões, devido a extensa área da bacia que amenizou consequentemente os efeitos hidrológicos.Palavras-chave: desmatamento; sensoriamento remoto; vazões. INFLUENCE OF THE LAND USE AND OCCUPATION IN HIDROLOGIC AVAILABILITY OF RIVER BASIN URUÇUÍ-PRETO, PIAUÍ ABSTRACT: The aim’s was to verify the influence of changes in land use and occupation in water availability in the river basin Uruçuí-Preto, Brazil, in the period 1984 to 2007. For the assessment of land use were used images from satellite Landsat 5 TM sensor (Thematic Mapper) and the classification of imagens was made by automatic supervised classification with the maximum likelihood algorithm. For the analysis of the hydrological behavior were used average flow data, maximum and minimum annual, minimum flow with seven days of annual duration (Q7) and flow rates associated with stays of 90% (Q90) and 95% (Q95) of the year. For the association between flow and land use was made the simple correlation between the variables, testing its 5% significance (p < 0.05). The results showed that when comparing the years 1984 and 2007, the Cerrado and Mata Riparian classes decreased 20.9% and 2.4% respectively, Solo Exposed / Crop Field class increased 13.48% and Burned Areas class increased by 9.83%. There were no significant correlations between changes of class variables in the use and occupation of land and the flows, due to the large area of the basin that has consequently reduced the hydrological effects.Keywords: deforestation; remote sensing; flow.
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Mendes Pereira, V., O. Brina, J. Bracken, T. Krings, K. Lovblad, F. van Nijnatten, D. Ruijters, and T. Grünhagen. "E-081 Assessment of the MAFA Ratio as a Quantitative Prognostic Marker of Aneurysm Occlusion after Flow Diverter Treatment." Journal of NeuroInterventional Surgery 8, Suppl 1 (July 2016): A84.2—A85. http://dx.doi.org/10.1136/neurintsurg-2016-012589.153.
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Sumin, A. N., A. V. Shcheglova, Yu S. Slepynina, A. V. Ivanova, and O. M. Polikutina. "Assessment of left ventricular diastolic dysfunction following anthracyclinebased chemotherapy in breast cancer patients." Acta Biomedica Scientifica 7, no. 3 (July 5, 2022): 121–33. http://dx.doi.org/10.29413/abs.2022-7.3.13.
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Cardiotoxicity is a side effect of anthracycline-based chemotherapy. Clinical and prognostic significance of left ventricular diastolic dysfunction in heart failure patients is undeniable.The aim. To assess dynamic changes in the left ventricular diastolic function after anthracycline-based chemotherapy (ANT) in breast cancer patients.Material and methods. The study included 40 women aged 35 to 72 years with breast cancer (BC) undergoing ANT chemotherapy. The main group (n = 40) consisted of women with breast cancer examined at admission, after 6 months the same women (n = 37) were examined again. Women without breast cancer (n = 25) were used as the control group.Results. Dynamic changes in mitral annular velocities were revealed by Doppler tissue imaging. Lateral early diastolic mitral annular velocity (e’ lateral) was significantly lower in breast cancer patients as compared to the control group (p = 0.031). Six months after ANT chemotherapy, there was a definite increase in the lateral late diastolic mitral annular velocity (a’ lateral) (p = 0.033). Average early diastolic transmitral flow velocity to early diastolic velocity (E/e’ lateral) ratio was within the normative values in all groups, but E/e’ lateral in the main group was higher compared to the control group (p = 0.003). In the main group, septal early diastolic mitral annular velocity (e’ septal) was lower compared to the control group (p = 0.0005). Moreover, an increase in the septal mitral annular velocity (a’ septal) (p = 0.01) and higher E/e’ septal ratio (p = 0.011) were revealed during dynamic observation. Multiple logistic regression disclosed that E/A, e’ lateral, e’/a’ lateral, and E/e’ lateral were affected by heart rate, psychological status, age, hypertension, and body mass index, but not anthracycline chemotherapy. The total dose of anthracycline was independently associated with e’ septal and E/e’ septal: F(4.18) = 16.466 (p < 0.001; R2 = 0.775) and F(3.16) = 7.271 (p = 0.004; R2 = 0.627).Conclusion. Left ventricular diastolic function worsens in women undergoing anthracycline-based chemotherapy for breast cancer (lower e’, e’/a’ lateral, and e’ septal, higher E/e’ septal ratio). However, anthracycline does not significantly affect LVEF and LV deformation indicators. E/e’ septalande’ septal are independently associated with the total dose of anthracycline.
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Lv, Maoting, Shanshan Yu, Yongzhen Li, Xiaoting Zhang, and Dan Zhao. "Ultrasound Multiparametric Assessment of the Impact of Hypertensive Disorders of Pregnancy on Fetal Cardiac Function and Growth and Development." Evidence-Based Complementary and Alternative Medicine 2022 (June 6, 2022): 1–6. http://dx.doi.org/10.1155/2022/3419966.
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Objective.To evaluate the ultrasound multiparametric assessment of the impact of hypertensive disorders of pregnancy (HDP) on fetal cardiac function and growth and development. Methods. In this prospective study, 98 cases of HDP treated in our institution were recruited into a study group, and 100 pregnant women with healthy singleton pregnancies were included in a control group. All eligible patients were also assigned to either study group A (HDP fetuses with growth restriction) or study group B (HDP fetuses with normal growth). Fetal echocardiography was performed on all eligible participants to obtain hemodynamic and cardiac function parameters for the evaluation of fetal growth and development, and the impact of HDP on fetal heart function and growth and development was analyzed. Results. HDP fetuses were associated with smaller head circumference, biparietal diameter, femoral length, and abdominal circumference versus healthy fetuses. The study group had a higher resistance index (RI) and pulsatility index (PI) of umbilical artery (UA), ductus venous (DV), pulmonary vein (PV), and lower RI and PI of aortic isthmus (AoI) than the control group. The study group showed higher left and right ventricular isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), and myocardial performance index (MPI) values and lower mitral and tricuspid E wave and E/A values than the control group. The systolic blood pressure was positively correlated with PI, RI of UA, DV, and PV, and left and right ventricular IVCT, IVRT, and MPI and negatively correlated with PI and RI of AoI and mitral and tricuspid E wave and E/A values of HDP fetuses. The peak systolic/diastolic flow rate (S/D), PI, and RI of umbilical blood flow in study group A were higher than those in study group B. Umbilical blood flow S/D showed the highest AUC and specificity for predicting fetal growth restriction, and PI had the highest sensitivity for predicting fetal growth restriction. Conclusion. HDP compromises fetal cardiac function and growth, and ultrasound multiparametric assessment provides accurate detection of fetal cardiac function and hemodynamics changes. The patient’s condition can be monitored through the assessment of ultrasound parameters of fetal growth and development.
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Li, Binghua, Jesús Garicano-Mena, Yao Zheng, and Eusebio Valero. "Dynamic Mode Decomposition Analysis of Spatially Agglomerated Flow Databases." Energies 13, no. 9 (April 28, 2020): 2134. http://dx.doi.org/10.3390/en13092134.
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Dynamic Mode Decomposition (DMD) techniques have risen as prominent feature identification methods in the field of fluid dynamics. Any of the multiple variables of the DMD method allows to identify meaningful features from either experimental or numerical flow data on a data-driven manner. Performing a DMD analysis requires handling matrices V ∈ R n p × N , where n p and N are indicative of the spatial and temporal resolutions. The DMD analysis of a complex flow field requires long temporal sequences of well resolved data, and thus the memory footprint may become prohibitively large. In this contribution, the effect that principled spatial agglomeration (i.e., reduction in n p via clustering) has on the results derived from the DMD analysis is investigated. We compare twelve different clustering algorithms on three testcases, encompassing different flow regimes: a synthetic flow field, a R e D = 60 flow around a cylinder cross section, and a R e τ ≈ 200 turbulent channel flow. The performance of the clustering techniques is thoroughly assessed concerning both the accuracy of the results retrieved and the computational performance. From this assessment, we identify DBSCAN/HDBSCAN as the methods to be used if only relatively high agglomeration levels are affordable. On the contrary, Mini-batch K-means arises as the method of choice whenever high agglomeration n p ˜ / n p ≪ 1 is possible.