43 research outputs found
Applied Calibration and Validation Method of Dynamic Process Simulation for Crushing Plants
There is a need within the production industry for digitalization and the development of meaningful functionality for production operation. One such industry is aggregate production, characterized by continuous production operation, where the digital transformation can bring operational adaptability to customer demand. Dynamic process simulations have the ability to capture the change in production performance of aggregate production over time. However, there is a need to develop cost-efficient methodologies to integrate calibrations and validation of models. This paper presents a method of integrating an experimental and data-driven approach for calibration and validation for crushing plant equipment and a process model. The method uses an error minimization optimization formulation to calibrate the equipment models, followed by the validation of the process model. The paper discusses various details such as experimental calibration procedure, applied error functions, optimization problem formulation, and the future development needed to completely realize the procedure for industrial use. The validated simulation model can be used for performing process planning and process optimization activities for the crushing plantâs operation
Contrast-enhanced magnetomotive ultrasound imaging (CE-MMUS) for colorectal cancer staging : assessment of sensitivity and resolution to detect alterations in tissue stiffness
A key challenge in the treatment of colorectal cancer is identification of the sentinel draining lymph node. Magnetomotive ultrasound, MMUS, has identified lymph nodes in rat models: superparamagnetic iron oxide nanoparticles (SPIONs) accumulated in the lymph are forced to oscillate by an external magnetic field; the resulting axial displacement is recovered allowing structure delineation with potential to indicate alterations in tissue stiffness, but it is limited by small vibration amplitudes. We propose CE-MMUS using SPION loaded microbubbles (SPION-MBs) to enhance sensitivity, reduce toxicity, and offer additional diagnostic or perfusion information. Laser doppler vibrometry measurements was performed on SPION containing tissue mimicking material during magnetic excitation. These measurements show a vibration amplitude of 279 ± 113 Όm in a material with Young's modulus of 24.3 ± 2.8 kPa, while the displacements were substantially larger, 426 ± 9 Όm, in the softer material, with a Young's modulus of 9.6 ± 0.8 kPa. Magnetic field measurement data was used to calibrate finite element modelling of both MMUS and CE-MMUS. SPION-MBs were shown to be capable of inducing larger tissue displacements under a given magnetic field than SPIONs alone, leading to axial displacements of up to 2.3x larger. A doubling in tissue stiffness (as may occur in cancer) reduces the vibration amplitude. Thus, there is potential for CE-MMUS to achieve improved stiffness sensitivity. Our aim is to define the potential contribution of CE-MMUS in colorectal cancer diagnosis and surgical guidance
Contrast enhanced magneto-motive ultrasound in lymph nodes - modelling and pre-clinical imaging using magnetic microbubbles
Despite advances in MRI, the detection and characterisation of lymph nodes in rectal cancer remains complex, especially when assessing the response to neo-adjuvant treatment. An alternative approach is functional imaging, previously shown to aid characterization of cancer tissues. We report proof-of-concept of the novel technique Contrast-Enhanced Magneto-Motive Ultrasound (CE-MMUS) to recover information relating to local perfusion and lymphatic drainage, and interrogate tissue mechanical properties through magnetically induced tissue deformations. The feasibility of the proposed application was explored using a combination of pre-clinical ultrasound imaging and finite element analysis. First, contrast enhanced ultrasound imaging on one wild type mouse recorded lymphatic drainage of magnetic microbubbles after bolus injection. Second, preliminary CE-MMUS data were acquired as a proof of concept. Third, the magneto-mechanical interactions of a magnetic microbubble with an elastic solid were simulated using finite element software. Accumulation of magnetic microbubbles in the inguinal lymph node was verified using contrast enhanced ultrasound, with peak enhancement occurring 3.7 s post-injection. Preliminary CE-MMUS indicates the presence of magnetic contrast agent in the lymph node. The finite element analysis explores how the magnetic force is transferred to motion of the solid, which depends on elasticity and bubble radius, indicating an inverse relation with displacement. Combining magnetic microbubbles with MMUS could harness the advantages of both techniques, to provide perfusion information, robust lymph node delineation and characterisation based on mechanical properties. Clinical Relevanceâ Robust detection and characterisation of lymph nodes could be aided by visualising lymphatic drainage of magnetic microbubbles using contrast enhanced ultrasound imaging and magneto-motion, which is dependent on tissue mechanical properties
Contrast enhanced magneto-motive ultrasound in lymph nodes - modelling and pre-clinical imaging using magnetic microbubbles
Despite advances in MRI, the detection and characterisation of lymph nodes in rectal cancer remains complex, especially when assessing the response to neo-adjuvant treatment. An alternative approach is functional imaging, previously shown to aid characterization of cancer tissues. We report proof-of-concept of the novel technique Contrast-Enhanced Magneto-Motive Ultrasound (CE-MMUS) to recover information relating to local perfusion and lymphatic drainage, and interrogate tissue mechanical properties through magnetically induced tissue deformations. The feasibility of the proposed application was explored using a combination of pre-clinical ultrasound imaging and finite element analysis. First, contrast enhanced ultrasound imaging on one wild type mouse recorded lymphatic drainage of magnetic microbubbles after bolus injection. Second, preliminary CE-MMUS data were acquired as a proof of concept. Third, the magneto-mechanical interactions of a magnetic microbubble with an elastic solid were simulated using finite element software. Accumulation of magnetic microbubbles in the inguinal lymph node was verified using contrast enhanced ultrasound, with peak enhancement occurring 3.7 s post-injection. Preliminary CE-MMUS indicates the presence of magnetic contrast agent in the lymph node. The finite element analysis explores how the magnetic force is transferred to motion of the solid, which depends on elasticity and bubble radius, indicating an inverse relation with displacement. Combining magnetic microbubbles with MMUS could harness the advantages of both techniques, to provide perfusion information, robust lymph node delineation and characterisation based on mechanical properties. Clinical Relevanceâ Robust detection and characterisation of lymph nodes could be aided by visualising lymphatic drainage of magnetic microbubbles using contrast enhanced ultrasound imaging and magneto-motion, which is dependent on tissue mechanical properties
Development of Magnetomotive Ultrasound Imaging
The earlier abnormalities coupled with disease can be discovered in the body, the larger is the chance to survive the disease. Molecular imaging is a growing research field which aims to detect these abnormalities at a molecular level, when the chance of survival is still high. The main idea of molecular imaging is to use target specific contrast agents that accumulate at the diseased region at a detectable concentration. Nanoparticles have shown to be very suitable as molecular imaging contrast agents due to their small size, which enable them to cross biological barriers and to bind to the biological entity of interest. In this thesis has the potential of magnetomotive ultrasound (MMUS), a new ultrasound imaging technique which enables detection of superparamagnetic iron oxide nanoparticles (SPIONs), been examined. Nanoparticles are too small to be detected with conventional ultrasound since their small size make them unable to backscatter ultrasound at a detectable level. Instead, MMUS imaging makes profits of the induced movement, created when a time-varying magnetic field is applied to a sample containing SPIONs. As the particles start to move, their surrounding will move and ultrasound is used to detect this motion. In the first study (paper I), was a frequency and phase tracking MMUS algorithm developed. The algorithm is able to filter out the nanoparticle movement from other artifactual movements and the location of the nanoparticles may then be revealed. To evaluate the potential of the developed algorithm, phantom studies (paper I, II and IV) were performed. Different parameters such as the nanoparticle concentration and the magnetic field frequency were altered in order to examine their impact on the magnetomotive displacement. Simulations were performed, where models of experimental setups were created. The results from the simulations were verified with the experimental findings (paper II and IV) and a good agreement was found. Moreover, to evaluate the potential of MMUS to be used in health care, animal studies have been performed (paper III, V and VI). In this thesis, the MMUS technique was evaluated in a clinical relevant model, where SPION-laden sentinel lymph nodes (SLNs) in rats were imaged. In this model MMUS was thought to serve as a complementary imaging modality to standard methods, providing high-resolution bedside surgical guidance during SLN surgery in breast cancer or malignant melanoma. In order to test the model in a clinical scenario, prestaging of the SPION-laden SLNs was done with MRI or PET (paper III and VI, respectively), thereafter MMUS imaging was performed. The results, both from the phantom and the animal studies, have shown to be very promising. Displacement in the sub-micrometer range has been detected in all studies. Although displacement artifacts have been more than two orders of magnitudes larger than the MMUS signal, the algorithm has been able to provide a clear representation of the location of the SPION-laden regions (e.g. paper III and V). This indicates that the MMUS technique has potential for future clinical use
"Thus bear witness to my manhood!" : Wilhelm Peterson-Berger's philosophy of art and perception of gender, with particular emphasis on the years 1896-1913
The overall purpose of this study is to elucidate Wilhelm Peterson-Bergerâs perception of gender and how it is manifested in his philosophy of art. His perception of gender also incorporates conceptions of history, music and nationality. The research question is analysed primarily by reviewing Peterson-Bergerâs writings from 1896 to 1913. The research is intended to shed new light on a previously overlooked area of research, using gender theory and discourse analysis. Peterson-Berger and his work have not been examined previously from a gender theory perspective.  The research shows that Peterson-Berger was influenced in large measure by the prevailing ideals of his time, although he was in some ways more innovative than many of his contemporaries. Around the turn of the 20th century there was a great deal of focus on biology, with  a clear distinction drawn between femininity and masculinity[1] . Masculinity was held up as an ideal, in contrast to femininity and effeminacy. Peterson-Berger advocated this distinction, and emphasized the biological  distinction between [2] masculinity and femininity. However, a man need not always have all the characteristics that were considered typically masculine for his time, nor was it necessary for a woman to possess all the feminine characteristics typical of the female gender. According to Peterson-Berger, a woman could have a masculine soul, and vice versa. And although he often took a negative view of women, he granted musical recognition to singers who realized music in what was, to him, a masculine way. Moreover, the majority of Peterson-Bergerâs close friends were women, and he dedicated many of his works to women. Theories of race and human evolution were circulating at the turn of the century, and clearly influenced Peterson-Berger. This study has shown that he pursued the writings of [3] Chamberlain[4] and Nietzsche. Incorporating elements of old Gothicist theories with ideas from the two aforementioned thinkers, Peterson-Berger constructed his own racial theory. He asserted that all peoples originated from the Nordic region, which he believed to be the birthplace of the entire human race. According to his theory, southern peoples were inferior[5] , with one exception, the Greeks, towards whom he was very positively disposed. This had to do with the ancient music drama, which Peterson-Berger believed had been created by inhabitants from the north who had migrated to Greece. Peterson-Bergerâs notions about peoples from the north versus peoples from the south were interwoven with theories of sexuality. He believed that Germanic peoples were more sexually abstemious than southern Europeans, and that peoples who lived in the south were sexually dissolute. To indulge oneâs sexuality was, in his view, a character flaw. Conversely, Peterson-Berger viewed asexuality as a masculine ideal, and believed it to be more common in the north.  A number of contradictions have emerged in his perceptions of race and sexuality. A number of his perceptions with respect to gender roles, sexuality, nationalism and philosophy[6] are portrayed in his opera Arnljot, as are the contradictions inherent in them. For instance, the character Arnljot has many of the typical masculine characteristics held up as ideal, but nevertheless exhibits both weaknesses and deficiencies. This is reflected in both the music and the opera libretto.   Wilhelm Peterson-Berger var en av de mest framstĂ„ende tonsĂ€ttarna kring sekelskiftet 1900. Han var inte bara kompositör utan Ă€ven aktiv skribent i daglighetspressen. MĂ„nga av hans uppfattningar om kön, nationalitet, filosofi och konst Ă„terspelglas i hans skriftstĂ€lleri men kan Ă€ven tydas i de musikaliska verken. Peterson-Berger var till stor del pĂ„verkad av dĂ„tidens rĂ„dande ideal, men pĂ„ vissa sĂ€tt var han mer nydanande Ă€n mĂ„nga andra i sin samtid. Omkring sekelskiftet sattes mycket fokus pĂ„ biologi och en tydlig uppdelning gjordes mellan kvinnligt och manligt. Manlighet stĂ€lldes upp som ett ideal i kontrast till kvinnlighet och omanlighet. Peterson-Berger föresprĂ„kar en sĂ„dan uppdelning och gör skillnad mellan biologisk manlighet och kvinnlighet. Dock behöver inte alltid en man förfoga över egenskaper som ansĂ„gs tidstypiskt manliga eller en kvinna inneha endast de tidstypiska kvinnliga egenskaperna. Enligt honom kunde en kvinna vara innehavare av en manlig sjĂ€l och vice versa. Peterson-Berger tangerade sĂ„ledes en modern syn pĂ„ kön som pekar fram mot dagens genus teorier. I Peterson-Bergers opera Arnljot konkretiseras flera av hans uppfattningar av bĂ„de könsroller, sexualitet och filosofi â liksom de motsĂ€gelser som fanns. KaraktĂ€ren Arnljot förfogar exempelvis över flera av de idealtypiska manliga egenskaperna men uppvisar trots det bĂ„de svagheter och brister. Det Ă„terspeglas sĂ„vĂ€l i text som i musik. Peterson-Bergers egen sexualitet har upprepade gĂ„nger varit omdiskuterad. Knyter vi an till hans musikaliska verk och skriftstĂ€lleri kommer vi nĂ€rmare ett svar pĂ„ hur det kan ha förhĂ„llit sig
LÀrarrollen, barninflytande och den förberedda miljön sett i tvÄ olika pedagogiska verksamheter
Vi har undersökt hur man inom en Reggio Emilia förskola och en montessoriförskola arbetar utifrÄn aspekter som lÀrarrollen, barninflytande och den förberedda miljön. VÄra frÄgestÀllningar Àr: Hur Àr miljön utformad utifrÄn aspekter som barnanpassning och inspiration för barnen pÄ en Reggio Emiliaförskola och en Montessoriförskola? PÄ vilket sÀtt har barnen inflytande enligt pedagogerna pÄ en Reggio Emiliainspirerad förskola och en Montessoriförskola? Vad har pedagogerna pÄ en Montessoriförskola och pÄ en Reggio Emilia inspirerad förskola för lÀrarroll och hur ser de sjÀlva pÄ den? Vi har gjort observationer och intervjuer pÄ tvÄ förskolor. Vi har utgÄtt frÄn lÀroplanen för förskolan, Lpfö98 och sedan sett hur man arbetar med de olika aspekterna i de bÄda förskolorna. Vi har kommit fram till att det finns mycket likheter i de olika arbetssÀtten, men ocksÄ en del skillnader. BÄda utgÄr frÄn barnet medan lÀraren har mer av en passiv roll. De arbetar bÄda med ett konkret material. Inom Montessoripedagogiken arbetar man med ett fÀrdigt material men inom Reggio Emilia arbetar man med allt som fantasin och omgivningen erbjuder. Barnens intresse ligger i grund för verksamheten pÄ bÄda förskolorna som vi undersökt och innemiljön Àr anpassad efter barnens behov och storlek
LÀrarrollen, barninflytande och den förberedda miljön sett i tvÄ olika pedagogiska verksamheter
Vi har undersökt hur man inom en Reggio Emilia förskola och en montessoriförskola arbetar utifrÄn aspekter som lÀrarrollen, barninflytande och den förberedda miljön. VÄra frÄgestÀllningar Àr: Hur Àr miljön utformad utifrÄn aspekter som barnanpassning och inspiration för barnen pÄ en Reggio Emiliaförskola och en Montessoriförskola? PÄ vilket sÀtt har barnen inflytande enligt pedagogerna pÄ en Reggio Emiliainspirerad förskola och en Montessoriförskola? Vad har pedagogerna pÄ en Montessoriförskola och pÄ en Reggio Emilia inspirerad förskola för lÀrarroll och hur ser de sjÀlva pÄ den? Vi har gjort observationer och intervjuer pÄ tvÄ förskolor. Vi har utgÄtt frÄn lÀroplanen för förskolan, Lpfö98 och sedan sett hur man arbetar med de olika aspekterna i de bÄda förskolorna. Vi har kommit fram till att det finns mycket likheter i de olika arbetssÀtten, men ocksÄ en del skillnader. BÄda utgÄr frÄn barnet medan lÀraren har mer av en passiv roll. De arbetar bÄda med ett konkret material. Inom Montessoripedagogiken arbetar man med ett fÀrdigt material men inom Reggio Emilia arbetar man med allt som fantasin och omgivningen erbjuder. Barnens intresse ligger i grund för verksamheten pÄ bÄda förskolorna som vi undersökt och innemiljön Àr anpassad efter barnens behov och storlek
Magnetomotive Ultrasound Imaging Systems : Basic Principles and First Applications
This review discusses magnetomotive ultrasound, which is an emerging technique that uses superparamagnetic iron oxide nanoparticles as a contrast agent. The key advantage of using nanoparticle-based contrast agents is their ability to reach extravascular targets, whereas commercial contrast agents for ultrasound comprise microbubbles confined to the blood stream. This also extends possibilities for molecular imaging, where the contrast agent is labeled with specific targeting molecules (e.g., antibodies) so that pathologic tissue may be visualized directly. The principle of action is that an external time-varying magnetic field acts to displace the nanoparticles lodged in tissue and thereby their immediate surrounding. This movement is then detected with ultrasound using frequency- or time-domain analysis of echo data. As a contrast agent already approved for magnetic resonance imaging (MRI) by the US Food and Drug Administration, there is a shorter path to clinical translation, although safety studies of magnetomotion are necessary, especially if particle design is altered to affect biodistribution or signal strength. The external modulated magnetic field may be generated by electromagnets, permanent magnets, or a combination of the two. The induced nanoparticle motion may also reveal mechanical material properties of tissue, healthy or diseased, one of several interesting potential future aspects of the technique