Добірка наукової літератури з теми "BIOENGINEERING WAY"

Abstract Soil bioengineering is part of vegetative land conservation activities, including covering all use of plants to maintain the carrying capacity of the land. The sustainability of coffee farming achievement in the upstream watershed area is closely related to the application of soil bioengineering technology. This study conducted to identify the recent studies of soil bioengineering technology and its application in coffee farming toward increasing the land productivity in the upstream watershed. The research location is a smallholder coffee plantation upstream of the Way Besay sub-watershed, spread over 3 sub-districts, Air Hitam, Way Tenong, and Sumber Jaya sub-District, West Lampung, Lampung, Indonesia. Coffee farmers as many as 167 people as respondents. The data analysis method used exploration of the applicability of soil bioengineering technology at the micro-level. The mapping of the role of soil bioengineering trace using the VosViewer tool. The results of the analysis show that the readiness level application of soil bioengineering technology in coffee farming includes the production and use of organic fertilizers made from local materials, the use of mulch as soil cover, agroforestry with a variety of tall canopy plants/MPTS, the planting of multiple cropping (planting various yielding crops), and plant diversification with alley planting. Soil bioengineering technology has a very high potential to increase land productivity to support sustainable coffee production in the upstream area of the Lampung watershed.

The author assesses the results of the Bioengineering Design Forum – a collaboration between university researchers, clinicians and industry in Ireland. The aim of the Forum is to initiate, develop and bring to a successful conclusion R&D collaborations that lead to new or improved medical devices. By laying down certain operating procedures for the Forum, an effective ‘meeting ground’ has been developed which serves the objectives of both university engineering departments and the medical device industry in a unique way. The purpose of this paper is to relate our experiences of the Forum; they may be useful to others who would like to attempt similar initiatives in other fields. The author also describes the results that may be expected from this kind of university–industry collaboration in practice.

ABSTRACTThe effects of conventional and novel methods for the manipulation of growth in meat animals are reviewed within the context of the fundamental laws that determine the biological efficiency of energy conversion. Interspecies comparisons reveal large differences in the energetic efficiency of growth between mammals and birds. The similarity between mammals of different sizes is remarkable, both between and within species, which suggests that manipulation of growth rate per se has little effect on efficiency. The best way to improve the efficiency of growth is to maximize the conversion of metabolizable energy (ME) to lean tissue at all stages of maturation. The principal destination of ME is heat, however thermogenesis linked to essential metabolic functions is resistant to manipulation. It is more profitable to manipulate the partition of retained energy between protein and fat. Whether this is achieved by nutrition, conventional breeding or bioengineering, it is necessary to ensure that it does not compromise the normal health and vigour of the growing animal.

ecent advances using bioengineering methods (e.g. biomaterials, 3D-printing, microfluidics tec.) has opened the possibility to study female reproductive system and reproductive diseases in a totally new way and with unpredictable perspectives

The plant’s property of arresting the soil by roots reinforcement technique reinforces the slopes and increases stability. Using vegetation in bioengineering offers a viable slope protection solution. As a result of soil problems in environmental applications and effective solid waste disposal, research has been done to examine the feasibility of employing solid wastes to enhance soil engineering behavior. In this paper, the mechanical effect of vegetation and solid waste on slope stability is calculated by studying the effect of vetiver grass composite with rice hush ash on the stability of the soil. Laboratory tests were performed for soil, vetiver, and RHA (rice husk ash) composite. At different RHA content of 5%, 10%, 15% & 20% mixed in the soil on which vetiver grass was planted. According to the test findings, soil+vetiver+10%RHA gives the highest strength among different compositions. Soil+vetiver+10%RHA increased shear strength overall, decreasing cohesiveness from 15.37 to 13.10 KPa and increasing the soil friction angle from 33.22⸰ to 40.96⸰ . Based on the results obtained from the direct shear test, the factor of safety (FOS) was determined with and without a composite of vetiver and 10%RHA content by using PLAXIS 2D at different slope angles(A) of 30.960 , 36.870 , and 450 . A maximum percentage increase in FOS was observed at 18.78% for soil+vetiver+10%RHA with respect to bare soil at a slope of 45⸰ . This study offers a scientific explanation for the impact of plant and RHA cover on the stability of the slope.

The aim of the paper was to determine the influence of root systems of chosen tree species found in the Polish Flysch Carpathians on the increase of soil shear strength (root cohesion) in terms of slope stability. The paper's goal was achieved through comprehensive tests on root systems of eight relatively common in the Polish Flysch Carpathians tree species. The tests that were carried out included field work, laboratory work and analytical calculations. As part of the field work, the root area ratio (A IA) of the roots was determined using the method of profiling the walls of the trench at a distance of about 1.0 m from the tree trunk. The width of the. trenches was about 1.0 m, and their depth depended on the ground conditions and ranged from 0.6 to 1.0 m below the ground level. After preparing the walls of the trench, the profile was divided into vertical layers with a height of 0.1 m, within which root diameters were measured. Roots with diameters from 1 to 10 mm were taken into consideration in root area ratio calculations in accordance with the generally accepted methodology for this type of tests. These measurements were made in Biegnik (silver fir), Ropica Polska (silver birch, black locust) and Szymbark (silver birch, European beech, European hornbeam, silver fir, sycamore maple, Scots pine, European spruce) located near Gorlice (The Low Beskids) in areas with unplanned forest management. In case of each tested tree species the samples of roots were taken, transported to the laboratory and then saturated with water for at least one day. Before testing the samples were obtained from the water and stretched in a. tensile testing machine in order to determine their tensile strength and flexibility. In general, over 2200 root samples were tested. The results of tests on root area ratio of root systems and their tensile strength were used to determine the value of increase in shear strength of the soils, called root cohesion. To this purpose a classic Wu-Waldron calculation model was used as well as two types of bundle models, the so called static model (Fiber Bundle Model — FIRM, FBM2, FBM3) and the deformation model (Root Bundle Model— RBM1, RBM2, mRBM1) that differ in terms of the assumptions concerning the way the tensile force is distributed to the roots as well as the range of parameters taken into account during calculations. The stability analysis of 8 landslides in forest areas of Cicikowicleie and Wignickie Foothills was a form of verification of relevance of the obtained calculation results. The results of tests on root area ratio in the profile showed that, as expected, the number of roots in the soil profile and their ApIA values are very variable. It was shown that the values of the root area ratio of the tested tree species with a diameter 1-10 ram are a maximum of 0.8% close to the surface of the ground and they decrease along with the depth reaching the values at least one order of magnitude lower than close to the surface at the depth 0.5-1.0 m below the ground level. Average values of the root area ratio within the soil profile were from 0.05 to 0.13% adequately for Scots pine and European beech. The measured values of the root area ratio are relatively low in relation to the values of this parameter given in literature, which is probably connected with great cohesiveness of the soils and the fact that there were a lot of rock fragments in the soil, where the tests were carried out. Calculation results of the Gale-Grigal function indicate that a distribution of roots in the soil profile is similar for the tested species, apart from the silver fir from Bie§nik and European hornbeam. Considering the number of roots, their distribution in the soil profile and the root area ratio it appears that — considering slope stability — the root systems of European beech and black locust are the most optimal, which coincides with tests results given in literature. The results of tensile strength tests showed that the roots of the tested tree species have different tensile strength. The roots of European beech and European hornbeam had high tensile strength, whereas the roots of conifers and silver birch in deciduous trees — low. The analysis of test results also showed that the roots of the studied tree species are characterized by high variability of mechanical properties. The values Of shear strength increase are mainly related to the number and size (diameter) of the roots in the soil profile as well as their tensile strength and pullout resistance, although they can also result from the used calculation method (calculation model). The tests showed that the distribution of roots in the soil and their tensile strength are characterized by large variability, which allows the conclusion that using typical geotechnical calculations, which take into consideration the role of root systems is exposed to a high risk of overestimating their influence on the soil reinforcement. hence, while determining or assuming the increase in shear strength of soil reinforced with roots (root cohesion) for design calculations, a conservative (careful) approach that includes the most unfavourable values of this parameter should be used. Tests showed that the values of shear strength increase of the soil reinforced with roots calculated using Wu-Waldron model in extreme cases are three times higher than the values calculated using bundle models. In general, the most conservative calculation results of the shear strength increase were obtained using deformation bundle models: RBM2 (RBMw) or mRBM1. RBM2 model considers the variability of strength characteristics of soils described by Weibull survival function and in most cases gives the lowest values of the shear strength increase, which usually constitute 50% of the values of shear strength increase determined using classic Wu-Waldron model. Whereas the second model (mRBM1.) considers averaged values of roots strength parameters as well as the possibility that two main mechanism of destruction of a root bundle - rupture and pulling out - can occur at the same. time. The values of shear strength increase calculated using this model were the lowest in case of beech and hornbeam roots, which had high tensile strength. It indicates that in the surface part of the profile (down to 0.2 m below the ground level), primarily in case of deciduous trees, the main mechanism of failure of the root bundle will be pulling out. However, this model requires the knowledge of a much greater number of geometrical parameters of roots and geotechnical parameters of soil, and additionally it is very sensitive to input data. Therefore, it seems practical to use the RBM2 model to assess the influence of roots on the soil shear strength increase, and in order to obtain safe results of calculations in the surface part of the profile, the Weibull shape coefficient equal to 1.0 can be assumed. On the other hand, the Wu-Waldron model can be used for the initial assessment of the shear strength increase of soil reinforced with roots in the situation, where the deformation properties of the root system and its interaction with the soil are not considered, although the values of the shear strength increase calculated using this model should be corrected and reduced by half. Test results indicate that in terms of slope stability the root systems of beech and hornbeam have the most favourable properties - their maximum effect of soil reinforcement in the profile to the depth of 0.5 m does not usually exceed 30 kPa, and to the depth of 1 m - 20 kPa. The root systems of conifers have the least impact on the slope reinforcement, usually increasing the soil shear strength by less than 5 kPa. These values coincide to a large extent with the range of shear strength increase obtained from the direct shear test as well as results of stability analysis given in literature and carried out as part of this work. The analysis of the literature indicates that the methods of measuring tree's root systems as well as their interpretation are very different, which often limits the possibilities of comparing test results. This indicates the need to systematize this type of tests and for this purpose a root distribution model (RDM) can be used, which can be integrated with any deformation bundle model (RBM). A combination of these two calculation models allows the range of soil reinforcement around trees to be determined and this information might be used in practice, while planning bioengineering procedures in areas exposed to surface mass movements. The functionality of this solution can be increased by considering the dynamics of plant develop¬ment in the calculations. This, however, requires conducting this type of research in order to obtain more data.

AbstractIn his 1966 John Danz lectures, Francis H. C. Crick decried vitalism in the life sciences. Why did he do this three decades after most historians and philosophers of science regarded vitalism as dead? This essay argues that, by advocating the reduction of biology to physics and chemistry Crick was: (a) attempting to imbue the life sciences with greater prestige, (b) paving the way for bioengineering and the reduction of consciousness to molecules, and (c) trying to root out religious sentiment in the life sciences. In service of these goals, Crick deployed vitalism as a straw man enemy. His wave of so-called vitalists in the middle of the twentieth century in fact raised legitimate questions regarding the relationship of organisms to their DNA molecules that Crick was ill-equipped to answer. Moreover, most were not vitalists at all but advocates for what I term bioexceptionalism—an argument for the methodological utility of keeping biological pursuits within their own domains, distinct from physics and chemistry, regardless of the ontological status of living things. Nevertheless, Crick’s status as a “cross-worlds influencer” entrenched a philosophically-enervated reductionism in the life sciences for decades.

<em>Abstract.</em>—Although many hydroelectric dams have fishways for upstream passage of migratory fish, passage delays often occur at these sites. Migrational delay may affect fish detrimentally in several ways, including depletion of energy reserves, suboptimal arrival timing at spawning sites, and prolonged exposure to hazardous conditions at the face of dams. We applied time-to-event analyses to passage times of radio-tagged adult Chinook salmon <em>Oncorhynchus tshawytscha </em>at four dams on the lower Columbia River, where many fish require several days to pass each dam. The analysis allowed us to determine instantaneous passage rates in response to fluctuating river conditions. By relating variability in passage rate to the predictor variables river temperature, river flow, and fish size, we determined the relative contribution of various factors to the passage time of migrating fish. We fit the model by maximizing the likelihood function that incorporated information from individuals rather than aggregated groups of fish. We used Akaike’s Information Criterion to distinguish among several competing models, each of which used a different predictor variable. We found that daytime passage rates were significantly greater than nighttime passage rates. Also, the influence of river flow, river temperature, and fish length on passage rates varied at the four dams. However, when a factor had a significant influence on passage time, the direction of the relationship was consistent across dams: river flow and fish length were positively related to passage time (greater values led to longer passage time), and river temperature was negatively related. This method is easily adaptable to study passage time of any fish population facing a broad range of obstacles to migration, whether natural or man-made.

<em>Abstract.</em>—Although many hydroelectric dams have fishways for upstream passage of migratory fish, passage delays often occur at these sites. Migrational delay may affect fish detrimentally in several ways, including depletion of energy reserves, suboptimal arrival timing at spawning sites, and prolonged exposure to hazardous conditions at the face of dams. We applied time-to-event analyses to passage times of radio-tagged adult Chinook salmon <em>Oncorhynchus tshawytscha </em>at four dams on the lower Columbia River, where many fish require several days to pass each dam. The analysis allowed us to determine instantaneous passage rates in response to fluctuating river conditions. By relating variability in passage rate to the predictor variables river temperature, river flow, and fish size, we determined the relative contribution of various factors to the passage time of migrating fish. We fit the model by maximizing the likelihood function that incorporated information from individuals rather than aggregated groups of fish. We used Akaike’s Information Criterion to distinguish among several competing models, each of which used a different predictor variable. We found that daytime passage rates were significantly greater than nighttime passage rates. Also, the influence of river flow, river temperature, and fish length on passage rates varied at the four dams. However, when a factor had a significant influence on passage time, the direction of the relationship was consistent across dams: river flow and fish length were positively related to passage time (greater values led to longer passage time), and river temperature was negatively related. This method is easily adaptable to study passage time of any fish population facing a broad range of obstacles to migration, whether natural or man-made.

Abstract<em>.</em>—Side channels are recognized as an important habitat component for stream resident species such as coho salmon <em>Oncorhynchus kisutch</em>. The objectives of this study were to (1) design, construct, and monitor a natural-like channel for rearing coho salmon, and (2) demonstrate an alternative rearing technique that could be incorporated into hatchery operations. Data on migration, growth, habitat use, and ultimately return rates were collected. A 286-m-long channel containing riffles, pools, ponds, alcoves, and abundant large woody debris was constructed. Discharge was set at 0.1 m3/s and was adjustable from 0 to 0.3 m³/s. Channel width averaged 1.2 m and had a surface area of 971 m². Invertebrate drift was supplemented with a prepared diet. Fifty thousand eyed coho eggs were incubated in the channel. The resulting fry were enumerated at the tail works and allowed to emigrate so that fish residence in the channel was volitional. Out-migration was high initially, dropped in the summer, and spiked over a 3-d period in the fall before slowing during winter followed by a distinct spring out-migration. Habitat use was quantified through visual counts, snorkeling, and underwater video. Densities of fish were approximately seven times higher than comparable natural habitat. Smolts leaving the channel in the spring equated to 1.5 fish/m², which is higher than most comparable natural habitat. We concluded that engineered channels could volitionally support numbers of fish at densities higher than in natural habitat, that fish behavior in them was comparable to wild fish, and that engineered channels could be used by hatchery programs thus contributing to hatchery reform.

Abstract<em>.</em>—Side channels are recognized as an important habitat component for stream resident species such as coho salmon <em>Oncorhynchus kisutch</em>. The objectives of this study were to (1) design, construct, and monitor a natural-like channel for rearing coho salmon, and (2) demonstrate an alternative rearing technique that could be incorporated into hatchery operations. Data on migration, growth, habitat use, and ultimately return rates were collected. A 286-m-long channel containing riffles, pools, ponds, alcoves, and abundant large woody debris was constructed. Discharge was set at 0.1 m3/s and was adjustable from 0 to 0.3 m³/s. Channel width averaged 1.2 m and had a surface area of 971 m². Invertebrate drift was supplemented with a prepared diet. Fifty thousand eyed coho eggs were incubated in the channel. The resulting fry were enumerated at the tail works and allowed to emigrate so that fish residence in the channel was volitional. Out-migration was high initially, dropped in the summer, and spiked over a 3-d period in the fall before slowing during winter followed by a distinct spring out-migration. Habitat use was quantified through visual counts, snorkeling, and underwater video. Densities of fish were approximately seven times higher than comparable natural habitat. Smolts leaving the channel in the spring equated to 1.5 fish/m², which is higher than most comparable natural habitat. We concluded that engineered channels could volitionally support numbers of fish at densities higher than in natural habitat, that fish behavior in them was comparable to wild fish, and that engineered channels could be used by hatchery programs thus contributing to hatchery reform.

Cancer deaths are mostly caused by the metastasis of the malignant cells, not by the parent tumor itself. During metastasis, cancer cells detach from the parent tumor, spread to different tissues via blood circulation or lymph system, and reattach to invade new tissues and organs. Adhesivity plays a crucial role throughout the metastasis process.

Abstract On the maintenance carried out by OCENSA for slope stabilization in areas with geotechnical issues, protection of lateral streams’ banks, maintenance of the Right of Way (RoW) embankment or access roads, sheet piles have been successfully used. The paper describes the different alternatives and their uses. Among them are: terraces to facilitate drainage and plant recovery, PVC sheet piles for protection of stream banks, sheet piles made of carbon steel pipe and steel deck in which the piles can be driven by percussion or previously excavated with drilling machine.

Bioengineering is a technological miracle of health care and future health hope. From the entrepreneurial contributions of William Kolff with the original handmade dialysis machine to the application of the x-ray to medical diagnostics and treatment, biomedical pioneers brought technology to medical care, often at great personal risk. Few can conceive the magnitude of the impact of technology on our ability to return the sick and disabled to function. The “simple” steel and plastic hip implant is a technological wonder. The human is the most demanding of systems to be repaired by technology. The stress levels, cycle loading, chemical degradation and even biological rejection are without precedent in engineering application. Reliability is expected to be near 100%. Psychological and cosmetic compatibility are severe constraints. The current quality of life of many (if not most) of us is dependent upon technology, and forefront technology at that. The dentist no longer hurts and our teeth last longer. Numerous “replacements” are cosmetically acceptable. Medical diagnosties are everywhere, but have a long way to go. Emergency medicine is high-tech. The wonders of bioengineering are in our present and in our future. It is informative to review our bioengineering heritage from early orthopedics (splints, peg legs and crutches), through mobility facilitation (wheelchairs) and internal repair (aortic patches and arterial replacement) to modern diagnostics (MRI) and organ replacement (artificial hearts, kidneys, etc.). A recent renewed interest in biomedical devices paralleling the decoding of the genome and the proposed genetic future portends what Dr. Francis Fukuyama of Johns Hopkins called “Our Post Human Future.” We will explore our historical pathway to what we will call “our better human future through bioengineering.”

Biomechanics courses often attract students from diverse academic backgrounds including a mix of engineers and scientists. A Journal Club, in which students read and discuss articles from scientific literature, is a collaborative learning activity that is accessible to students from these diverse scientific backgrounds. Journal Clubs originated as way to cost-share periodicals [1] and have evolved as educational tools. Journal Clubs in medical education [2–4] are cited for both increasing medical knowledge in 88% of medical residents [2] and bridging the gap between research and clinical practice. [1] In an extensive literature review, 80% of 101 studies reported that Journal Club discussions improved knowledge and critical appraisal skills. [5] Journal Club format is flexible and no strong preference in method has emerged in the literature. [2] The present work describes a structured Journal Club that has been implemented in a biomechanics course for three years and presents results from student surveys.

Traditionally the validation process of FE models is carried on by visually comparing two curves, respectively from an experimental test and the numerical simulation. A more rigorous way to quantitative compare two curves in the validation process would be provided by comparison metrics. In this work the component validation of the Finite Element model of a Knee-Thigh-Hip complex was carried on by quantitatively comparing the results from the experimental tests with the corresponding numerical curves. An LSDYNA finite element model of the lower extremities was developed and the condyle, pelvis and femur and components were carefully validated using three comparison metrics. The good match.

Traditionally, the interactions of drugs and toxicants with human tissue have been investigated in a reductionist way—for example, by focusing on specific molecular targets and using single-cell-type cultures before testing compounds in whole organisms. More recently, “systems biology” approaches attempt to enhance the predictive value of in vitro biological data by adopting a comprehensive description of biological systems and using computational tools that are sophisticated enough to handle the complexity of these systems. However, the utility of computational models resulting from these efforts completely relies on the quality of the data used to construct them. Here, we propose that recent advances in the development of bioengineered, three-dimensional, multicellular constructs provide in vitro data of sufficient complexity and physiological relevance to be used in predictive systems biology models of human responses. Such predictive models are essential to maximally leveraging these emerging bioengineering technologies to improve both therapeutic development and toxicity risk assessment. This brief outlines the opportunities presented by emerging technologies and approaches for the acceleration of drug development and toxicity testing, as well as the challenges lying ahead for the field.