cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Anisotropic thermal expansion and magnetostriction of YNi$_2$B$_2$C single crystals
Creators: name: Bud'ko, S. L.
name: Schmiedeshoff, G. M.
name: Lapertot, G.
name: Canfield, P. C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present results of anisotropic thermal expansion and low temperature magnetostriction measurements on YNi$_2$B$_2$C single crystals grown by high temperature flux and floating zone techniques. Quantum oscillations of magnetostriction were observed at low temperatures for $H \| c$ starting at fields significantly below $H_{c2}$ ($H < 0.7 H_{c2}$). Large irreversible, longitudinal magnetostriction was seen in both, in-plane and along the c-axis, directions of the applied magnetic field in the intermediate superconducting state. Anisotropic uniaxial pressure dependencies of $T_c$ were evaluated using results of zero field, thermal expansion measurements.
Sum-frequency excitation of coherent magnons
Creators: name: Juraschek, Dominik M.
name: Wang, Derek S.
name: Narang, Prineha
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Coherent excitation of magnons is conventionally achieved through Raman scattering processes, in which the difference-frequency components of the driving field are resonant with the magnon energy. Here, we describe mechanisms by which the sum-frequency components of the driving field can be used to coherently excite magnons through two-particle absorption processes. We use the Landau-Lifshitz-Gilbert formalism to compare the spin-precession amplitudes that different types of impulsive stimulated and ionic Raman scattering processes and their sum-frequency counterparts induce in an antiferromagnetic model system. We show that sum-frequency mechanisms enabled by linearly polarized driving fields yield excitation efficiencies comparable or larger than established Raman techniques, while elliptical polarizations produce only weak and circularly polarizations no sum-frequency components at all. The mechanisms presented here complete the map for dynamical spin control by the means of Raman-type processes.
Surface morphology and mechanical properties of a microwave plasma assisted chemical vapor deposited micro textured carbide layer on Co-Cr-Mo alloy used for artificial joints
Creators: name: Amanuel, Yared
Publisher: name: Maryland Shared Open Access Repository
Year: 2008
Subjects: Engineering, Mechanical (0548)

description: The reduction of wear for metal-on-metal implantable materials is proposed by the deposition of a micro-textured carbide surface layer (referred to as ""brain coral""). Formation of the micro-textured carbide surface has been developed using a microwave plasma-assisted chemical vapor deposition process (MPCVD). The mechanical properties and surface morphology of this surface have been shown to play an important role in its rate and mechanism of wear.  In this study, the elastic modulus, hardness and contact stiffness were determined by nanoindentation techniques. In addition, the micro-hardness of the micro-textured surface was determined using microindentation techniques. The surface profile parameters (Ra, rms and PV and peak area) were measured using a white light profilometer (WLISP). The effect of deposition processing time on the morphology and mechanical properties was also investigated. The WLISP image of the carbide layer surface profile exhibited the ""brain coral"" pattern after 2 hours of deposition time. The 4-hour deposition processing time yielded the optimal surface morphology with a mature ""brain coral"" surface structure that has an overall surface average roughness (Ra) of 0.55 (± 0.17) m. In contrast, the peak areas, which include the contacting areas, have an Ra of 0.22 (± 0.09) m. The micro-hardness of the CoCrMo alloy, the ""as-deposited"" and polished micro-textured carbide surfaces were found to be 7.30 (± 0.5) GPa, 10.2 (± 1.2) GPa and 8.21 (± 1.07) GPa, respectively. The nano-hardness of the polished micro-textured carbide was determined to be 15 (± 4) GPa, in contrast that observed for the native CoCrMo alloy (9 (± 0.3) GPa). The reduced modulus and contact stiffness for the micro-textured carbide surface were 254 (± 18) Gpa and 170 (± 15) GPa. These values are slightly higher than those observed for the CoCrMo alloy.  The similarity in the values of reduced modulus for both the carbide layer and the substrate is important in reducing failure due to fracture toughness. Preliminary results suggest that the coefficient of friction (CoF) of micro-textured carbide surface on stainless steel is comparable to steel 1045 on stainless steel. The enhanced mechanical properties and morphological advantages of the micro-textured surface, together with its potential lubricant and debris trapping ability, makes it an attractive material for use in metal-on-metal joint replacement applications.
Social Withdrawal during Middle Childhood in Turkey: The Role of Individual, Parenting, and Peer Factors
Creators: name: Bayram Ozdemir, Sevgi
Publisher: name: Maryland Shared Open Access Repository
Year: 2012
Subjects: coping
parenting
peer relationships
shyness
social withdrawal
Turkey

description: This dissertation project aimed to examine the meaning of social withdrawal in an inter-dependent cultural context (Turkey), its correlates, and the risk and protective factors for withdrawn children's adjustment across two consecutive studies.  In Study 1, semi-structured interviews with Turkish children (n = 15), mothers (n = 13), and teachers (n = 13) were conducted to identify the behavioral and motivational descriptors of social withdrawal.  Similar to Western conceptualizations of social withdrawal, the results confirmed the presence of shyness and unsociability.  A new subtype, regulated withdrawal, was also revealed, which refers to such behaviors as adopting a passive role in social groups, overly regulating behaviors, and suppressing wishes and desires in social relationships, with the motivation of fitting into the group and maintaining harmonious relations with others.  Study 2A examined the factor structure, measurement invariance across informants (children and mothers), reliability, and validity of the Child Social Preference Scale (CSPS), which was revised based on the findings from Study 1.  Participants included 599 children aged 9-11 years and their mothers (n = 571), and teachers of a subset of the sample (n = 20).  The results suggested that the CSPS-R had the same factor structure across the child- and mother-rated forms.  However, the child-rated CSPS-R appeared to be a more valid measure of social withdrawal than the mother-rated form.  Using the same sample as Study 2A, Study 2B examined the correlates and moderators of withdrawn behaviors on child adjustment.  Shyness was found to be related with a wider range of child adjustment difficulties than unsociability and regulated withdrawal, although all forms of withdrawal were associated with child adjustment difficulties.  Analyses of the risk and protective factors suggested that the moderating roles of individual, parenting, and peer level factors varied by the different forms of withdrawn behaviors.  Overall, this dissertation research contributed to the development of a culturally based understanding of socially withdrawn behaviors in an interdependent cultural context.  Universal and cultural-specific processes are discussed with regard to their theoretical and practical implications for socially withdrawn children's adjustment.
กระบวนการเรียนรู้ลำตัดตามแนวพระราชปณิธาน สืบสาน รักษา และต่อยอด: กรณีศึกษาแหล่งเรียนรู้มรดกภูมิปัญญาทางวัฒนธรรมลำตัดและเพลงพื้นบ้านภาคกลางพ่อหวังเต๊ะ - แม่ศรีนวล
Creators: name: อธิชนัน สิงหตระกูล
Publisher: name: บัณฑิตศึกษา สถาบันบัณฑิตพัฒนศิลป์ กระทรวงวัฒนธรรม
Year: 2023
Subjects: ลำตัด
มรดกภูมิปัญญาทางวัฒนธรรม
กระบวนการเรียนรู้
กระบวนกร
พระราชปณิธาน

description: วิพิธพัฒนศิลป์, 3, 3, 49-66
SoftSeparator:  A Method for Dynamic Separation of the Signatures Generated by Two Cows Walking in Tandem over the Longitudinally-Split Floor of the StepMetrixTM
Creators: name: Dyer, Philip
Publisher: name: Maryland Shared Open Access Repository
Year: 2007
Subjects: automation
separation
lameness
dairy
stepmetrix
Engineering, Mechanical (0548)

description: Due to a herd mentality and some styles of management, dairy cows will often bunch together when walking in dairy lanes.  This bunching causes data loss for automatic walk-through devices placed in the lanes that require cows to pass through one at a time.  The StepMetrixTM is such a device developed for early detection of hind-limb lameness in individual cows.  The system utilizes a split-floor design with loadcells to record and analyze the ground reaction forces generated by a cow's walk after milking.  The analysis uses a statistical model to produce an SMXTM score, which is associated with the probability of a cow being lame.; Upon examination of hundreds of data signatures, it was discovered that certain signatures have data generated by hind limbs that can be extracted to be used in the statistical lameness model.  Specific types of steps produced by two cows walking in tandem were identified, and cutoffs were found for specific metrics to enable automatic detection of those step types.  Using basic assumptions about the walk of a cow, the SoftSeparatorTM identifies specific step sequences to recognize where data generated by hind limbs is present and then extracts the data. The results of the SoftSeparatorTM algorithm were tested on 200 data files generated at two different farms.  In its best incarnation, SoftSeparatorTM successfully extracted 509 instances of hind-limb data out of 629 total instances, while incorrectly extracting only 25 instances.  These results show that SoftSeparatorTM effectively recovers much of the lost data.
Searches for new sources of CP violation using molecules as quantum sensors
Creators: name: Hutzler, N. R.
name: Borschevsky, A.
name: Budker, D.
name: DeMille, D.
name: Flambaum, V. V.
name: Gabrielse, G.
name: Ruiz, R. F. Garcia
name: Jayich, A. M.
name: Orozco, L. A.
name: Ramsey-Musolf, M.
name: Reece, M.
name: Safronova, M. S.
name: Singh, J. T.
name: Tarbutt, M. R.
name: Zelevinsky, T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We discuss how molecule-based searches offer complementary probes to study the violation of fundamental symmetries. These experiments have the potential to probe not only the electron EDM, but also hadronic CPV phenomena. Future experimental developments will offer generic sensitivity to probe flavor neutral sources of both leptonic and hadronic CPV at scales of $\geq$ 100 TeV, and flavor changing CPV at scales of $\geq$ 1000 TeV.
Evolution of Yield Surfaces and Texture with Finite Plastic Deformation in Aluminum Alloys
Creators: name: Pandey, Amit
Publisher: name: Maryland Shared Open Access Repository
Year: 2009
Subjects: Aluminum
Finite deformation
Magnesium
Neutron Diffraction
Texture
Yield Surfaces

description: The primary objectives of this study are to determine the i) evolution of subsequent yield surfaces based on 10microstrain deviation from linearity; and ii) to report a comprehensive study of anisotropy and texture evolution with finite plastic deformation. The first study gives comprehensive experimental results on subsequent yield surfaces of a high work hardening alloy under proportional and non proportional loading paths. The size of yield surfaces under non-proportional loading decrease and no cross-effect is observed; these yield surfaces are completely different under proportional loading where the size of the yield surfaces increase and show positive cross-effect. The experimental results on subsequent yield surfaces after proportional loading paths under tension-tension stress space, for a very low and a very high work hardening Al alloy, using 10microstrain deviation from linearity as the definition of yield are presented. Subsequent yield surfaces are determined under axial, hoop, and combined hoop and axial proportional loading directions at various levels of plastic strain in each direction. Elastic moduli are also determined within each subsequent yield surface. Further, comprehensive responses of Al5754 and AZ31 are measured over wide ranges of strain rates and temperatures on same batch of two materials. These include the strain hardening, anisotropy, and texture evolution with finite plastic deformation. Tension, compression, and simple shear experiments at wide ranges of strain rates and temperatures are performed in rolling, transverse to rolling, and 45 to rolling directions. In addition, compression experiments were also performed in thickness direction. A new simple shear device is fabricated to perform simple shear experiments at elevated temperatures. Texture measurements are performed using neutron diffraction and EBSD in order to understand the deformation mechanisms of various specimens after finite deformation.
The impact of a fossil magnetic field on dipolar mixed-mode frequencies in sub- and red-giant stars
Creators: name: Bugnet, L.
name: Prat, V.
name: Mathis, S.
name: García, R. A.
name: Mathur, S.
name: Augustson, K.
name: Neiner, C.
name: Thompson, M. J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Stars more massive than $\sim 1.3$ M$_\odot$ are known to develop a convective core during the main-sequence: the dynamo process triggered by this convection could be the origin of a strong magnetic field inside the core of the star, trapped when it becomes stably stratified and for the rest of its evolution. The presence of highly magnetized white dwarfs strengthens the hypothesis of buried fossil magnetic fields inside the core of evolved low-mass stars. If such a fossil field exists, it should affect the mixed modes of red giants as they are sensitive to processes affecting the deepest layers of these stars. The impact of a magnetic field on dipolar oscillations modes was one of Pr. Michael J. Thompson's research topics during the 90s when preparing the helioseismic SoHO space mission. As the detection of gravity modes in the Sun is still controversial, the investigation of the solar oscillation modes did not provide any hint of the existence of a magnetic field in the solar radiative core. Today we have access to the core of evolved stars thanks to the asteroseismic observation of mixed modes from CoRoT, Kepler, K2 and TESS missions. The idea of applying and generalizing the work done for the Sun came from discussions with Pr. Michael Thompson in early 2018 before we loss him. Following the path we drew together, we theoretically investigate the effect of a stable axisymmetric mixed poloidal and toroidal magnetic field, aligned with the rotation axis of the star, on the mixed modes frequencies of a typical evolved low-mass star. This enables us to estimate the magnetic perturbations to the eigenfrequencies of mixed dipolar modes, depending on the magnetic field strength and the evolutionary state of the star. We conclude that strong magnetic fields of $\sim$ 1MG should perturbe the mixed-mode frequency pattern enough for its effects to be detectable inside current asteroseismic data.
description: Conference proceeding, in press, 7 pages, 3 figures
Responses of Engineering Materials, Anisotropy and Forming Limit Diagrams at different strain-rates and temperatures.
Creators: name: Baig, Muneer
Publisher: name: Maryland Shared Open Access Repository
Year: 2009

description: The objectives of this work are 1) to predict the yield locus, 2) normal anisotropic ratio (R-value), 3) stress response and 4) Forming Limit Diagram (FLD) of an aluminum alloy sheet, at different strain-rates using an appropriate anisotropic yield criterion and constitutive model. In order to achieve these objectives, a comprehensive study of quasi-static and dynamic responses of two FCC metals is performed to understand the material behaviors at large deformations and over wide ranges of strain-rate (103-10-5s-1) and temperature (223-755K). The two FCC metals include Oxygen Free High Conductivity (OFHC) copper and an aluminum alloy (AA5182), which have applications in the defense and automotive industries, respectively. In the case of AA5182, the material includes the base alloy and welded materials called Tailor Welded Blanks (TWBs). Quasi-static tensile strain-rate jump experiments at room temperature are performed on aluminum alloy (AA5182) sheet. Tensile split-Hopkinson pressure bar (SHPB) experimental setup is developed to perform tensile experiments at high strain rates and at different temperatures. Further, to determine the anisotropy in the material, several experiments are performed in different directions of the sheet metal. It was observed that AA5182-O exhibited negative and positive strain-rate sensitivities at room and 473K, respectively. The r-value increased with increase in temperature. The comprehensive study of OFHC copper includes results from quasi-static compression experiments performed at different strain-rates and temperatures. Dynamic compression experiments performed using the conventional SHPB technique are also presented. The material responses under quasi-static and dynamic torsion loading conditions, using the MTS and torsional Kolsky bar respectively, are also presented. The compressive responses of the material under non-proportional paths are also studied at different strain rates. Constitutive modeling of this comprehensive response is performed using a modified phenomenological model earlier developed by Khan et al. (1999 & 2004). This constitutive model captures the experimental response reasonably well (within 2%) given the few material constants involved and the ease with which they can be obtained. To remove any doubts of bias, this model is also used to correlate and predict the experimental observations on the same material by McDowell et al. (1999), and Nemat-Nasser et al. (1998). The correlations and predictions are again in good agreement with the experimental results. In conclusion, this model shows excellent capability to correlate and predict the experimental response of FCC and BCC metals and can be used in predicting the FLD for the aluminum alloy.
A study of C4H3N isomers in TMC-1: line by line detection of HCCCH2CN
Creators: name: Marcelino, N.
name: Tercero, B.
name: Agundez, M.
name: Cernicharo, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present Yebes 40m telescope observations of the three most stable C4H3N isomers towards the cyanopolyyne peak of TMC-1. We have detected 13 transitions from CH3C3N (A and E species), 16 lines from CH2CCHCN, and 27 lines (a-type and b-type) from HCCCH2CN. We thus provide a robust confirmation of the detection of HCCCH2CN and CH2CCHCN in space. We have constructed rotational diagrams for the three species, and obtained rotational temperatures between 4-8 K and similar column densities for the three isomers, in the range (1.5-3)e12 cm-2. Our chemical model provides abundances of the order of the observed ones, although it overestimates the abundance of CH3CCCN and underestimates that of HCCCH2CN. The similarity of the observed abundances of the three isomers suggests a common origin, most probably involving reactions of the radical CN with the unsaturated hydrocarbons methyl acetylene and allene. Studies of reaction kinetics at low temperature and further observations of these molecules in different astronomical sources are needed to draw a clear picture of the chemistry of C4H3N isomers in space.
description: Accepted for publication in A&A Letters
The relationships between gender, academic support, and academic    outcomes in high achieving African American students
Creators: name: Pollard, Shauna Alease
Publisher: name: Maryland Shared Open Access Repository
Year: 2009
Subjects: Academic achievement
African American
College
Gender
Graduate school
Social support

description: African Americans males are achieving at lower levels than African American females at every level of the educational pipeline. There is a paucity of research that examines factors that contribute to these gender differences, particularly among high achieving African American students. The current study examined gender differences in academically-focused social support from parents, teachers, and peers among high achieving African American students entering college.  Interactions between gender and academic social support in terms of predicting college and post-college academic success were also examined. The sample included African Americans (n=325) who entered UMBC's Meyerhoff Scholars Program between 1992 and 2001.  There was no relationship found between gender and levels of pre-college academic social support, or any gender differences in the ability of the pre-college support variables to predict undergraduate GPA. However, gender did interact with both father and teacher support to predict graduate enrollment. The implications of these findings are discussed.
Responses and constitutive modeling of aluminum alloys, and strain-rate and temperature dependent failure criteria for F.C.C. and H.C.P. metals
Creators: name: Liu, Haowen
Publisher: name: Maryland Shared Open Access Repository
Year: 2011
Subjects: Anisotropy
Constitutive model
Failure criterion
Strain Rate
Temperature
Tension compression asymmetry

description: The thermo-mechanical response of Al 2024-T351 under uniaxial compression loading are presented. Below certain threshold temperature, negligible strain-rate sensitivity is observed during quasi-static regime, while significant strain rate sensitivity is measured at dynamic strain-rates. Above threshold temperature, increasing strain-rate sensitivity has been observed. Based on these observations, KHL phenomenological constitutive model is significantly modified to predict the mechanical behavior of the alloy. Correlations with this modified model are shown very close to the observed responses. The second aim of this investigation is to establish a universal, accurate and robust failure criterion for ductile solids. New experimental results, along with published data on the Al 2024-T351 alloy by Stoughton and Yoon (2011), are used to establish a phenomenological failure criterion using the magnitude of stress vector and the first invariant of stress tensor. Moreover, the proposed failure criterion is used for prediction of the published results by Bruenig et al. (2008). This proposed isotropic failure criterion, based on the magnitude of stress vector (MSV), is further developed to include strain rate and temperature dependences. Based on experiment results, an exponential loading is included to simulate the strain rate effect; the KHL hardening model type temperature dependent term is also included to correlate with the observed temperature sensitivity of the failure of Al2024-T351 alloy. These modifications allow the proposed MSV failure criterion to predict the failure of Al 2024-T351 alloy over wide ranges of strain rate and temperature. Further, by demonstrating the influence of hydrostatic pressure on the anisotropic failure behavior of a HCP alloy, a new uncoupled anisotropic failure criterion is established. To comprehensively consider the anisotropy and tension compression asymmetry in the Ti-6Al-4V alloy, the modified Hill anisotropic function proposed by Khan and Yu (2011b), is used to describe the geometry of the anisotropic failure loci in principal stress space. Moreover, the KHL hardening mode type strain rate and temperature terms are adopted in the new anisotropic failure criterion to predict the failure strength of the Ti-6Al-4V alloy. Excellent correlation between predicted failure loci and the corresponding failure observations is demonstrated.
Sequential Optimal Designs with Unknown Link Function
Creators: name: Warfield, Joseph Davis
Publisher: name: Maryland Shared Open Access Repository
Year: 2008
Subjects: Bayesian Nonparametrics
Constrained Optimality
Generalized Linear Model
Isotonic Smoothing Spline
Sequential Design, Statistics (0463)

description: Optimal designs provide a very efficient way to maximize the amount of information gained in an experiment. For linear models the information is a factor of the covariates, but for non-linear models maximizing the information becomes more difficult because of the relationship of information with the unknown parameter. To efficiently utilize the information gained, we consider sequential optimal designs. The work in this paper deals with sequential designs for binary regression and Poisson regression models, where the link functions are from a location scale family. In both cases, we assume the functional form of the link function, F, to be known, such as logistic or probit. That leads to the unknown parameters ? and ? and quantiles of the curve being of primary interest. We provide an empirical study to investigate the robustness of several sequential designs for binary regression models under different stimulus-response curves for two binaryregression applications: Phase I clinical trial and reliability sensitivity testing. The analysis involves studying the properties of the design measure and the parameter estimates. We propose nonparametric estimation of the stimulus-response curve via isotonic smoothing spline estimator under monotonicity constraint and incorporate the estimator into the sequential allocation scheme. This makes the procedure more robust against incorrect specification of the stimulus-response curve and at the same time maintains the objective of efficient estimation.  We extend both the study and the proposed estimator to the Poisson regression model. We provide some theoretical results for the ISS sequential design algorithm and formulate the semiparametric Bayesian sequential optimal design approach for the binary regression model, which involves placing a prior distribution on the using mixtures of Dirichlet process priors.
Studies in Translation Discrimination, Termination, and Frameshifting
Creators: name: Taliaferro, Dwayne Lamon
Publisher: name: Maryland Shared Open Access Repository
Year: 2008
Subjects: ribosome
frameshifting
termination
telomerase
EST3
accuracy
Biology, Molecular (0307)
Biology, Microbiology (0410)

description: This dissertation utilized genetic manipulation of rRNA and mRNA to understand the molecular interactions that are pertinent in translation discrimination, termination and programmed frameshifting. Discrimination In Escherichia coli the nucleotides guanosine 530 (G530) and adenosine 1492 (A1492) are located across from each other in the ribosomal A site and play critical roles in the selection of tRNA. Mutations in these positions are dominant lethal independently, but have not been analyzed together. Molecular dynamics simulations predicted that mutations G530 to A and A1492 to G would create ribosomes functionally comparable to wildtype. This work found no mutations in 530 or 1492 that produced significant ribosome activity. Simulations predicted that A1408 may inhibit A1492G mutant activity. Mutations were made in A1408 with 530 and 1492 double mutants. There was no combination of triple mutations created that restored wildtype-comparable activity. It is likely that G530 and A1492 are functionally constrained in ways other than their hydrogen bonding. The nucleotide following UGA (UGAN) and mutations in 16S rRNA residue 1054 (normally C1054) can affect stop codon recognition by Escherichia coli release factor 2 (RF2). Their effects on UGA stop codon recognition have not been directly studied together. Analysis of UGAN and 1054 mutation during frameshifting and readthrough events suggested that the two residues do not directly interact to recruit RF2. Two models suggesting the role of both residues in RF2 recruitment are presented. Frameshift Stimulation ; EST3 protein is a component of the telomerase holoenzyme in Saccharomyces cerevisiae. The gene requires programmed frameshifting at the sequence CUU-AGU-U to produce a protein required for telomerase activity. The frameshift efficiency of the complete EST3 gene is 45%. However the frameshifting efficiency at the sequence CUU-AGU-U alone is only 6%. These data suggest that since the observed level of frameshifting in the EST3 gene is much higher than the EST3 frameshift sequence alone, the higher level of frameshifting is generated by a contribution from the gene's context. A 27 nucleotide sequence, called the EST3 stimulator, was isolated downstream from the frameshift site that stimulates frameshifting 8 fold.
IMPROVING UPSTREAM BIOPROCESSING BY ENABLING PROCESS SCOUTING DEVICES WITH LOW COST, DISPOSABLE OXYGEN AND pH SENSORS
Creators: name: Vallejos, Jose Reynaldo
Publisher: name: Maryland Shared Open Access Repository
Year: 2011
Subjects: Cell culture
kla
optical sensors
process development
process transfer
scale-up Cell culture
scale-up

description: Bioprocess information generated at the Process Scouting Devices (PSDs)-scale (<100mL) constitutes the initial building block upon which an industrial bioprocess is developed. Despite the key role that they play in bioprocess development, PSDs often lack the capability of monitoring the critical cell culture process parameters (e.g. dissolved oxygen (DO), pH, substrate consumption, product formation, etc.), and measuring certain engineering physical characteristics (e.g.  ,  , mixing time). As a result there is a process information gap between un-instrumented PSDs and fully instrumented lab cell culture devices that makes the process transfer from research to manufacturing scale more of an art than a science. In this project we have equipped T-flasks, small-scale spinner flasks and novel PSDs such as SuperSpinner D 1000® with low cost disposable dissolved oxygen and pH sensors which can convert these un-instrumented PSDs to cell culture devices that can provide greater quantitative process information. By taking this approach, we have been able to 1)	Convert T-flasks into novel upstream bioprocessing tools for scale-up/down applications such as cell clone stability testing. We observed from DO and pH profiles that after cell vial thaw significant biochemical pathway changes can occur during extended cell passaging in static T-flasks. Our on-line monitoring of pH and DO profiles picked the metabolic shifts ten passages earlier that the off-line sampling methods.  2)	Develop empirical mass transfer correlations for rocking and shaken T-flasks and compare the oxygen transfer capabilities of these sensor enabled T-flasks with other PSDs such as spinner flasks. We observed that rocking/shaken T-flasks have superior mass transfer coefficient (kLa) than novel  and traditional PSDs such as CultiFlask 50, SuperSpinner D 1000® and standard spinner flasks. 3)	Provide a novel vial thaw and inoculum expansion train (rocking) with on-line monitoring capabilities for critical cell culture parameters such as DO and pH. We have observed that a design space based on kLa or DO can be developed at the PSDs-scale and integrated with bench-scale devices (and beyond).  As a first step, this project shows how patch-based disposable optical technology can aid integrating research and manufacturing scales by using chemical engineering principles (mass transfer). We hypothesize that a robust and predictable bioprocess can be obtained by providing the cells with similar DO levels (or mass transfer coefficients) at every step of the bioprocess development cycle and thereby enabling implementation of Process Analytical Technology (PAT).
On the longitudinal vibration of a moving elevator cable-car system
Creators: name: Chen, Yi
Publisher: name: Maryland Shared Open Access Repository
Year: 2008
Subjects: dynamics
vibration

description: The vibration and noise problem has been a major challenge in the design and installation of an elevator system. While the transverse vibration of a moving hoist cable has been recently studied, the longitudinal vibration of a moving elevator cable-car system has not been studied. In this work, a new mathematical model for the longitudinal vibration of a moving elevator cable-car system with an arbitrary movement profile is developed. The car is modeled as a mass-spring-damper subsystem attached to the lower end of the cable. Both the Newtonian method and Hamilton's principle are used to derive the governing equations of the moving cable-car system.  The assumed modes method and a new spatial discretization method are used to discretize either the governing partial differential equation of the moving cable or the Lagrangian of the system before the application of Lagrange's equations. The rate of change of the total mechnaical energy is analyzed from the system viewpoint and the control volume viewpoint.  An energy flux is defined to describe the rate of energy transfer at the upper boundary of the cable. Numerical simulation of the responses from three spatial discretization schemes are obtained and compared. A definition of the equilibrium position of the system is discussed, and the dynamic responses around the equilibrium position are obtained. The new spatial discretization method can achieve uniform convergence and overcome the drawbacks of the classical assumed modes method.
Vanishing of Drude weight in interacting fermions on Zd with quasi-periodic disorder
Creators: name: Mastropietro, Vieri
Publisher: name: arXiv
Year: 2021
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We consider a fermionic many body system in Zd with a short range interaction and quasi-periodic disorder. In the strong disorder regime and assuming a Diophantine condition on the frequencies and on the chemical potential, we prove at $T=0$ the exponential decay of the correlations and the vanishing of the Drude weight, signaling Anderson localization in the ground state. The proof combines Ward Identities, Renormalization Group and KAM Lindstedt series methods.
description: 20 pages, 5 pictures
DETECTION AND LOCALIZATION OF HARDWARE TROJANS THROUGH ANALYSIS OF POWER PORTS TRANSIENT SIGNALS
Creators: name: MohammadPourRad, Reza
Publisher: name: Maryland Shared Open Access Repository
Year: 2008
Subjects: Hardware
Security
Transient signal
Trojan
VLSI
Computer Science (0984)

description: Security agencies have recently emphasized their concerns about the validity and trustability of mission critical chips fabricated overseas. These concerns originate from the non-securable conditions of the fabrication facilities and the possibility that adversaries may attempt to insert hardware components to critical application chips and cause the chips to fail during mission or leak information. The research reported in this dissertation is focused on developing screening methods that can be employed to evaluate the chips received from fabrication facility and determine whether or not such hardware Trojans exist in the dies. The proposed techniques are based on regional and statistical analysis of transients currents measured from the chip power ports and are not only capable of detecting  Trojans in a die but also can locate the position of Trojans in the chip with resolutions down to few gates. One main obstacle in all current-based test and analysis methods is the increasing rates of process and environmental variations that make the currents measured from dies of the same type of chip dramatically different from each other. Therefore, applying the statistical analysis directly to the currents measured from the chips will not be able to define thresholds for identifying Trojan-inserted chips from Trojan-free chips. A major part of the work reported in this thesis is on devising calibration methods that can be applied to the chip currents and reduce the effects of process and environmental variations.  Experiments reported here demonstrate that these calibration techniques are very effective and can help determine the statistical thresholds for Trojan-free chips and make the analysis sensitive the Trojans of very small number of gates.
Contribution to understanding the mathematical structure of quantum mechanics
Creators: name: Skala, L.
name: Kapsa, V.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Probabilistic description of results of measurements and its consequences for understanding quantum mechanics are discussed. It is shown that the basic mathematical structure of quantum mechanics like the probability amplitudes, Born rule, commutation and uncertainty relations, probability density current, momentum operator, rules for including the scalar and vector potentials and antiparticles can be obtained from the probabilistic description of results of measurement of the space coordinates and time. Equations of motion of quantum mechanics, the Klein-Gordon equation, Schrodinger equation and Dirac equation are obtained from the requirement of the relativistic invariance of the space-time Fisher information. The limit case of the delta-like probability densities leads to the Hamilton-Jacobi equation of classical mechanics. Many particle systems and the postulates of quantum mechanics are also discussed.
description: 21 pages
On Artin's Conjecture: Pairs of Additive Forms
Creators: name: Kaesberg, Miriam Sophie
Publisher: name: arXiv
Year: 2020
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11D88, 11D72

description: It is established that for every pair of additive forms $f=\sum_{i=1}^s a_i x_i^k, g=\sum_{i=1}^s b_i x_i^k$ of degree $k$ in $s>2k^2$ variables the equations $f=g=0$ have a non-trivial $p$-adic solution for all odd primes $p$.
VLT photometry in the Antlia Cluster: the giant ellipticals NGC 3258 and NGC 3268 and their globular cluster systems
Creators: name: Bassino, Lilia P.
name: Richtler, Tom
name: Dirsch, Boris
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a deep VLT photometry in the regions surrounding the two dominant galaxies of the Antlia cluster, the giant ellipticals NGC 3258 and NGC 3268. We construct the luminosity functions of their globular cluster systems (GCSs) and determine their distances through the turn-over magnitudes. These distances are in good agreement with those obtained by the SBF method. There is some, but not conclusive, evidence that the distance to NGC 3268 is larger by several Mpc. The GCSs colour distributions are bimodal but the brightest globular clusters (GCs) show a unimodal distribution with an intermediate colour peak. The radial distributions of both GCSs are well fitted by de Vaucouleurs laws up to 5 arcmin. Red GCs present a steeper radial density profile than the blue GCs, and follow closely the galaxies' brightness profiles. Total GC populations are estimated to be about 6000+/-150 GCs in NGC 3258 and 4750+/-150 GCs in NGC 3268. We discuss the possible existence of GCs in a field located between the two giant galaxies (intracluster GCs). Their luminosity functions and number densities are consistent with the two GCSs overlapping in projection.
description: 13 pages, 16 figures. Accepted for publication in MNRAS
Surface Densities Prewet a Near-Critical Membrane
Creators: name: Rouches, Mason
name: Veatch, Sarah
name: Machta, Benjamin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Subcellular Processes (q-bio.SC)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Recent work has highlighted roles for thermodynamic phase behavior in diverse cellular processes. Proteins and nucleic acids can phase separate into three-dimensional liquid droplets in the cytoplasm and nucleus and the plasma membrane of animal cells appears tuned close to a two-dimensional liquid-liquid critical point. In some examples, cytoplasmic proteins aggregate at plasma membrane domains, forming structures such as the post-synaptic density and diverse signaling clusters. Here we examine the physics of these surface densities, employing minimal simulations of co-acervating polymers coupled to an Ising membrane surface in conjunction with a complementary Landau theory. We argue that these surface densities are a novel phase reminiscent of pre-wetting, in which a molecularly thin three-dimensional liquid forms on a usually solid surface. However, in surface densities the solid surface is replaced by a membrane with an independent propensity to phase separate. We show that proximity to criticality in the membrane dramatically increases the parameter regime in which a pre-wetting-like transition occurs, leading to a broad region where coexisting surface phases can form even when a bulk phase is unstable. Our simulations naturally exhibit three surface phase coexistence even though both the membrane and the polymer bulk can only display two phase coexistence on their own. We argue that the physics of these surface densities enables diverse functions seen in Eukaryotic cells.
Rede des Ökumenischen Patriarchen Bartholomaios bei der Verleihung der Ehrendoktorwürde seitens der Evangelisch-Theologischen Fakultät der Universität Tübingen
Creators: name: Bartholomaios, Patriarch
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 66 Nr. 3 (2017): Ökumenische Rundschau, Band 66, Heft 3
HyperTendril: Visual Analytics for User-Driven Hyperparameter Optimization of Deep Neural Networks
Creators: name: Park, Heungseok
name: Nam, Yoonsoo
name: Kim, Ji-Hoon
name: Choo, Jaegul
Publisher: name: arXiv
Year: 2020
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: To mitigate the pain of manually tuning hyperparameters of deep neural networks, automated machine learning (AutoML) methods have been developed to search for an optimal set of hyperparameters in large combinatorial search spaces. However, the search results of AutoML methods significantly depend on initial configurations, making it a non-trivial task to find a proper configuration. Therefore, human intervention via a visual analytic approach bears huge potential in this task. In response, we propose HyperTendril, a web-based visual analytics system that supports user-driven hyperparameter tuning processes in a model-agnostic environment. HyperTendril takes a novel approach to effectively steering hyperparameter optimization through an iterative, interactive tuning procedure that allows users to refine the search spaces and the configuration of the AutoML method based on their own insights from given results. Using HyperTendril, users can obtain insights into the complex behaviors of various hyperparameter search algorithms and diagnose their configurations. In addition, HyperTendril supports variable importance analysis to help the users refine their search spaces based on the analysis of relative importance of different hyperparameters and their interaction effects. We present the evaluation demonstrating how HyperTendril helps users steer their tuning processes via a longitudinal user study based on the analysis of interaction logs and in-depth interviews while we deploy our system in a professional industrial environment.
description: Will be presented at IEEE VAST 2020 and published in IEEE Transactions on Visualization and Computer Graphics
Strong one-pion decay of $Σ_c$, $Σ_c^*$ and $Ξ_c^*$
Creators: name: Albertus, C.
name: Hernandez, E.
name: Nieves, J.
name: Verde-Velasco, J. M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Working in the framework of a nonrelativistic quark model we evaluate the widths for the strong one-pion decays $Σ_c\toΛ_c π$, $Σ_c^*\toΛ_c π$ and $Ξ_c^{*}\toΞ_c π$. We take advantage of the constraints imposed by heavy quark symmetry to solve the three-body problem by means of a simple variational ansatz. We use partial conservation of the axial current hypothesis to get the strong vertices from weak axial current matrix elements. Our results are in good agreement with experimental data.
description: 3 latex pages. Contribution to the Proceedings of the Quark Confinement and the Hadron Spectrum VII Conference (QCHS7) Ponta Delgada (PT) Sept 2-7, 2006
Distinguishing power-law uniform random graphs from inhomogeneous random graphs through small subgraphs
Creators: name: Stegehuis, Clara
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: Probability (math.PR)
subject: FOS: Mathematics

description: We investigate the asymptotic number of induced subgraphs in power-law uniform random graphs. We show that these induced subgraphs appear typically on vertices with specific degrees, which are found by solving an optimization problem. Furthermore, we show that this optimization problem allows to design a linear-time, randomized algorithm that distinguishes between uniform random graphs and random graph models that create graphs with approximately a desired degree sequence: the power-law rank-1 inhomogeneous random graph. This algorithm uses the fact that some specific induced subgraphs appear significantly more often in uniform random graphs than in rank-1 inhomogeneous random graphs.
Fundamental parameters of six neglected old open clusters
Creators: name: Carraro, Giovanni
name: Subramaniam, Annapurni
name: Janes, Kenneth A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this paper we present the first $BVI$ CCD photometry of six overlooked old open clusters (Berkeley 44, NGC 6827, Berkeley 52, Berkeley 56, Skiff 1 and Berkeley 5) and derive estimates of their fundamental parameters by using isochrones from the Padova library (Girardi et al. 2000). We found that all the clusters are older than the Hyades, with ages ranging from 0.8 (NGC 6827 and Berkeley 5) to 4.0 (Berkeley 56) Gyr. This latter is one of the old open clusters with the largest heliocentric distance. In the field of Skiff 1 we recognize a faint blue Main Sequence identical to the one found in the background of open clusters in the Second and Third Galactic Quadrant, and routinely attributed to the Canis Major accretion event. We use the synthetic Color Magnitude Diagram method and a Galactic model to show that this population can be easily interpreted as Thick Disk and Halo population toward Skiff 1. We finally revise the old open clusters age distribution, showing that the previously suggested peak at 5 Gyr looses importance as additional old clusters are discovered.
description: in publication in MNRAS
Techniques for Imaging Produce to Improve Food Safety and Quality
Creators: name: Motabar, Payam
Publisher: name: Maryland Shared Open Access Repository
Year: 2010
Subjects: Fecal contamination
Fluorescence
Food safety
Hyperspectral Imaging
Machine Vision
Tomatoes

description: This report presents the development of a pre-harvest method and post-harvest technique used to image produce in order to improve food safety and quality. The pre-harvest method includes developing a time-resolved, hyperspectral line scan laser-induced fluorescence imaging system to detect fecal contamination in crop fields. Experimental studies show the effective homogenization of the system's laser and the ability of this system to accurately detect an artificially contaminated apple. The post-harvest technique involves orienting tomatoes to facilitate machine vision for non-destructive imaging. This expands on previous studies that indicate the ability to orient quasi-round fruit their inertial properties. Orientation test were conducted using three tomato cultivars which represented the extremes in potential shapes of tomatoes. Results support the theoretical finding that elongated and squat objects are relatively easy to orient, and round objects are difficult to orient. Both devices are commercially-viable and address the current needs of the food industry.