Non-Intrusive Sensor for In-Situ Measurement of Recession Rate of Ablative and Eroding Materials

A non-intrusive sensor for in-situ measurement of recession rate of heat shield ablatives. An ultrasonic wave source is carried in the housing. A microphone is also carried in the housing, for collecting the reflected ultrasonic waves from an interface surface of the ablative material. A time phasing control circuit is also included for time-phasing the ultrasonic wave source so that the waves reflected from the interface surface of the ablative material focus on the microphone, to maximize the acoustic pressure detected by the microphone and to mitigate acoustic velocity variation effects through the material through a de-coupling process that involves a software algorithm. A software circuit for computing the location off of which the ultrasonic waves scattered to focus back at the microphone is also included, so that the recession rate of the heat shield ablative may be monitored in real-time through the scan-focus approach

THE EFFECT OF DIGITALIS ON THE NORMAL ELECTROCARDIOGRAM

With the advent of newer leads to the electrocardiogram it has become necessary to repeat the observations that have been made in the past on the cardiographic changes following digitalis administration in healthy subjects. The main object of this work has been to determine the lead or leads most susceptible to the effects of digitalis as well as the design of the deformity produced in the tracing. The need for the investigation has arisen from the common practice of giving digitalis to a patient considered to have heart disease before the electrocardiogram is recorded as part of a special examination. Confusion in diagnosis is specially likely if chest pain is included among the symptoms-a circumstance that allots more than ordinary importance to changes in the electrocardiogram. Methods. The dosage of digitalis leaf was that customarily used in the continuous treatment of a patient needing it. It was, therefore, given in the first place as 2 grains (0-13 g.) daily and later increased to 3 grains (0-2 g.) daily. Rapid digitalization was not followed. Thirteen healthy medical students volunteered to take digitalis during a period of six to eight weeks when the total dosage was from 104 to 135 grains (6 9-9 g.). Digitalis was dispensed to each student when he attended the Cardiac Department to ensure accuracy in regard to the amount taken. A preliminary electrocardiogram was taken before th

Plasma Properties and Heating at the Anode of a 1 kW Arcjet Using Electrostatic Probes

263 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997.A 1 kW hydrazine arcjet thruster has been modified for internal probing of the near-anode boundary layer with an array of fourteen electrostatic micro-probes. The main objectives of this experimental investigation were to: (1) obtain axial and azimuthal distributions of floating potential \phi\sb{\rm f}, anode sheath potential \phi\sb{\rm s}, probe current density at zero volts j\sb{\rm a}, electron number density n\sb{\rm es}, electron temperature T\sb{\rm es}, and anode heating due to electrons q\sb{\rm e} for arc currents I\sb{\rm arc}, between 7.8 and 10.6 A, propellant flow rates m = 40-60 mg/s, and specific energies, 18.8 MJ/kg $\le$ P/m $\le$ 27.4 MJ/kg; (2) probe the anode boundary layer using flush-mounted and cylindrical micro-probes; (3) verify azimuthal current symmetry; (4) understand what affects anode heating, a critical thruster lifetime issue; and (5) provide experimental data for validation of the Megli-Krier-Burton (MKB) model. All of the above objectives were met through the design, fabrication and implementation of fourteen electrostatic micro-probes, of sizes ranging from 0.170 mm to 0.43 mm in diameter. A technique for cleaning and implementing these probes was developed. Two configurations were used: flush-mounted planar probes and cylindrical probes extended 0.10-0.30 mm into the plasma flow. The main results of this investigation are: (1) electrostatic micro-probes can successfully be used in the harsh environment of an arcjet; (2) under all conditions tested the plasma is highly non-equilibrium in the near-anode region; (3) azimuthal current symmetry exists for most operating conditions; (4) the propellant flow rate affects the location of maximum anode sheath potential, current density, and anode heating more than the arc current; (5) the weighted anode sheath potential is always positive and varies from 8-17 V depending on thruster operating conditions; (6) the fraction of anode heating varies from 18-24% of the total input power over the range of specific energies tested; and (7) based on an energy loss factor of $\delta$ = 1200, reasonable correlation between the experimental data and the MKB model was found.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Συσχέτιση του βάρους κύησης με το αποκτήθεν βάρος του παιδιού μέχρι το πρώτο έτος

Εισαγωγή: Η παχυσαρκία της μητέρας κατά την κύηση έχει σημαντικές επιπτώσεις στην υγεία, συμβάλλοντας στην αύξηση της νοσηρότητας και της θνησιμότητας τόσο για τη μητέρα όσο και για το παιδί. Η παιδική παχυσαρκία έχει αναδειχθεί σε ένα από τα μείζονα θέματα υγείας στη σύγχρονη κοινωνία. Σκοπός: Σκοπός της παρούσας εργασίας ήταν η συσχέτιση της πρόσληψης του βάρους της μητέρας κατά την κύηση με το αποκτηθέν βάρος του βρέφους στον 3ο, 6ο και 12ο μήνα της ζωής του. Υλικό και Μέθοδος: . Το δείγμα της μελέτης αποτέλεσαν 79 βρέφη και οι μητέρες τους τα οποία προσέρχονταν για παρακολούθηση σε ιδιωτικό παιδιατρικό ιατρείο για χρονική διάρκεια δύο ετών από τον Ιανουάριο του 2017-και τον Δεκέμβριο του 2018.Τα παιδιά υποβλήθηκαν σε μετρήσεις του βάρους τους κατά τη συμπλήρωση του 3ου, 6ου και 12ου μήνα της ζωής τους το οποίο αντίστοιχα συγκρίθηκε με το βάρος που πήρε η μητέρα τους κατά την εγκυμοσύνη. Εφαρμόστηκαν οι στατιστικές δοκιμασίες x2-test και Pearson correlation. Για την ανάλυση των δεδομένων της μελέτης χρησιμοποιήθηκαν τα προγράμματα SPSS ver 22 και το επίπεδο στατιστικής σημαντικότητας τέθηκε στο 0,5. Αποτελέσματα: Η μέση ηλικία της μητέρας ήταν 30,5±3,6, το προσληφθέν βάρος κατά την κύηση 15,7±5,9, ο ΔΜΣ της μητέρας 24,3±3,1, το βάρος γέννησης του παιδιού 3116,4gr±487,2gr..Η μεταβολή βάρους του βρέφους ήταν κατά το πρώτο τρίμηνο ήταν 2854,4±755,4gr, στο 6μηνο ήταν 4646,3±809,3gr, και στον 12ο μήνα 6947,6±990,1gr. Το βάρος γέννησης του παιδιού έχει θετική συσχέτιση με το προσληφθέν βάρος της μητέρας κατά την κύηση, p=0,012, με το προσληφθέν βάρος κατά το 1ο τρίμηνο, 2ο και 4ο p<0,001, αντίστοιχα. Επίσης, το προσληφθέν βάρος κατά την κύηση και το βάρος της μητέρας έχει θετική συσχέτιση με το βάρος του παιδιού στο 1ο έτος, p=0,028, και p=0,001, αντίστοιχα. Επίσης, ο ΔΜΣ της μητέρας έχει θετική συσχέτιση με το προσληφθέν βάρος κατά την κύηση, p<0,001. Συμπεράσματα: Διάφοροι παράγοντες που αφορούν τη μητέρα και το ίδιο το παιδί, τόσο προγεννητικά, περιγεννητικά και μεταγεννητικά ευθύνονται για τον βαθμό αύξησης του βάρους του παιδιού έως την ηλικία του ενός έτους, αλλά και στην μετέπειτα ζωή του.Introduction: Maternal obesity during pregnancy has significant health effects, contributing to increased morbidity and mortality for both the mother and the child. Childhood obesity has emerged as one of the major health issues in modern society. Purpose: The purpose of this study was to correlate the maternal weight gain during pregnancy with the infant weight gain in the 3rd, 6th and 12th months of life. Material and Method:. The sample of the study consisted of 79 infants and their mothers attending a private pediatric clinic for a period of two years from January 2017 to December 2018. Children weight measurements were performed at the completion of the 3rd, 6th and 12th month of their life, which was compared to the weight their mother gained during pregnancy. Statistical tests x2-test and Pearson correlation were applied at this study. The SPSS ver 22 was used to analyze the data of the study and the level of statistical significance was set to 0.5. Results: The mean age of the mother was 30.5 ± 3.6, pregnancy weight gain 15.7 ± 5.9, maternal BMI of 24.3 ± 3.1, birth weight of the child 3116.4 g ± 487.2gr. The change of the infant weight was 2854.4 ± 755.4gr in the first quarter, 4646.3 ± 809.3gr in the 6 months, and 6947.6 ± 990.1gr in the 12th month. The birth weight of the child has a positive correlation with maternal weight gained during pregnancy, p = 0.012, with weight gained in the first trimester, 2nd and 4th p <0.001, respectively. Also, the weight put on during maternal pregnancy and the weight of mother has a positive correlation with the weight of the child in the first year, p = 0.028, and p = 0.001, respectively. Maternal BMI has a positive correlation with pregnancy gained weight, p <0.001. Conclusions: Various maternal and child-related factors, both prenatal, perinatal and postnatal, are responsible for the rate of increase of child's weight by the age of one year, as well as in his later lif

Understanding teacher use of the Internet as a new learning and teaching tool

This study explores one teacher\u27s use of the Internet technologies as a tool for instruction, following one middle school teacher with little Internet experience over the period of one academic year. It analyzes the ways this teacher makes sense of Internet technologies within the context of her professional beliefs and practices in the classroom. The study uses the qualitative methodology design of a study of a single case (Bogden & Biklen, 1992; Stake, 2000). Data are collected through field notes from participant-observation, interviews, reflective journals, printed Internet documents, and Internet exchanges. The data results are presented as a three layered analysis: a descriptive account of observational data about the teacher, her practices and her professional environment; a chronological account of the teacher\u27s journey over the period of the academic year; and an exploration of the central themes that emerged from the data. The results of the study provide descriptive insight into how a teacher learns to understand and use new instructional technologies, such as the Internet. Her experience aligns with adult learning behaviors and research from the Apple Classroom of Tomorrow (ACOT) project. She goes through significant stages from initial enthusiasm and discovery, to a period of conflict, which leads to critical reflection on the Internet as a tool for her classroom. Finally, she comes to terms with her misgivings and develops ways to use the Internet, which parallel models of use by other teachers. Significant categories of emergent themes include: the teacher has specific needs and conditions for learning the Internet; the teacher uses the Internet in defined ways; the teacher experiences a learning process; and the teacher learns within her community

Plasma Properties and Heating at the Anode of a 1 kW Arcjet Using Electrostatic Probes

263 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997.A 1 kW hydrazine arcjet thruster has been modified for internal probing of the near-anode boundary layer with an array of fourteen electrostatic micro-probes. The main objectives of this experimental investigation were to: (1) obtain axial and azimuthal distributions of floating potential \phi\sb{\rm f}, anode sheath potential \phi\sb{\rm s}, probe current density at zero volts j\sb{\rm a}, electron number density n\sb{\rm es}, electron temperature T\sb{\rm es}, and anode heating due to electrons q\sb{\rm e} for arc currents I\sb{\rm arc}, between 7.8 and 10.6 A, propellant flow rates m = 40-60 mg/s, and specific energies, 18.8 MJ/kg $\le$ P/m $\le$ 27.4 MJ/kg; (2) probe the anode boundary layer using flush-mounted and cylindrical micro-probes; (3) verify azimuthal current symmetry; (4) understand what affects anode heating, a critical thruster lifetime issue; and (5) provide experimental data for validation of the Megli-Krier-Burton (MKB) model. All of the above objectives were met through the design, fabrication and implementation of fourteen electrostatic micro-probes, of sizes ranging from 0.170 mm to 0.43 mm in diameter. A technique for cleaning and implementing these probes was developed. Two configurations were used: flush-mounted planar probes and cylindrical probes extended 0.10-0.30 mm into the plasma flow. The main results of this investigation are: (1) electrostatic micro-probes can successfully be used in the harsh environment of an arcjet; (2) under all conditions tested the plasma is highly non-equilibrium in the near-anode region; (3) azimuthal current symmetry exists for most operating conditions; (4) the propellant flow rate affects the location of maximum anode sheath potential, current density, and anode heating more than the arc current; (5) the weighted anode sheath potential is always positive and varies from 8-17 V depending on thruster operating conditions; (6) the fraction of anode heating varies from 18-24% of the total input power over the range of specific energies tested; and (7) based on an energy loss factor of $\delta$ = 1200, reasonable correlation between the experimental data and the MKB model was found.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Real-Time Ablation Recession Rate Sensor System for Advanced Reentry Vehicles

The development of a new sensor system for in-situ, real-time measurements of recession rate of heat shield ablative materials is described. The sensor utilizes a focused ultrasound approach to non-intrusively detect the ablative material’s surface loss while simultaneously correcting for acoustic velocity dependencies on temperature. The latter correction is done via an electronic-based scan-focus approach. The multi-source focusing approach is atypical of current ultrasound based sensors used for ablation recession rate measurement, which require a-priori knowledge of temperature distribution within the ablative to yield accurate data on recession rate. The paper describes the development of the sensor system resulting in a brassboard system that demonstrates its operational aspects and possibilities as a heat shield health monitoring system for future reentry vehicles

Systemic chemotherapy in inoperable or metastatic bladder cancer

Urothelial cancer is a common malignancy. The management of patients with recurrent disease after cystectomy or initially metastatic or unresectable disease represents a therapeutic challenge. Systemic chemotherapy prolongs survival but long-term survival remains infrequent. During recent years there has been improvement due to the use of novel chemotherapeutic agents, mainly gemcitabine and the taxanes. The long-considered-standard MVAC has been challenged by combinations showing more favourable toxicity profiles and equal (gemcitabine-cisplatin) or even improved (dose-dense, G-CSF-supported MVAC) efficacy. Specific interest has also been generated in specific groups of patients (elderly patients, patients with renal function impairment or comorbidities), who are not fit for the standard cisplatin-based chemotherapy but can derive significant benefit from carboplatin- or taxane-based treatment. Retrospective analyses have enabled the identification of groups of patients with different prognoses, who possibly require different therapeutic approaches. Modern chemotherapy offers a chance of long-term survival in patients without visceral metastases, possibly in combination with definitive local treatment. Finally, the progress of targeted therapies in other neoplasms seems to be reflected in advanced bladder cancer by recent studies indicating that biological agents can be combined with modern chemotherapy. The true role of such therapies is currently being evaluated

Modular Electromagnetic Transducer for Optimized Energy Transfer via Electric and/or Magnetic Fields

In this paper, a modular electromagnetic transducer that achieves the optimal transfer of energy from the electric and/or magnetic fields is proposed. Both the magnetic field resonance coupling and the influence of the electric field near the copper transducers of the printed circuit board and inside the FR4-type epoxy material are considered. In our printed arrays of flat transducers, we consider face-to-face capacitances for the study of resonance coupling. Because the space between coil turns is almost double the plate thickness, the coplanar capacitance can be ignored for frequencies under 2 MHz. A radio frequency (RF) transmitter and transducer were built to demonstrate the increased energy transfer efficiency when using both electric and magnetic fields in the near-field region. The transversal leakage flux coupling of a long RF coil was more efficient than a simple axial magnetic field coupling when using pancake transceiver coils. The optimal configuration having one long coil at the base and two or more flat coils as capacitor plates near coil ends generated the highest tandem of magnetic and electrical fields. A power regression tool was used to convert and simplify the transducer current and voltage variation with distance. In this regard, the current change corresponded to magnetic field variation and the voltage change to the electric field variation. New formulas for estimating the near-field region and the self-capacitance of the RF transformer coil are proposed; the optimal function in the frequency domain for a given transducer distance was defined by simulation