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T C Miller

Publications and source records attributed to T C Miller.

At least 19 recordsLinked to original sources

Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector.

Data from the AMANDA-B10 detector taken during the austral winter of 1997 have been searched for a diffuse flux of high energy extraterrestrial muon neutrinos. This search yielded no excess events above those expected from background atmospheric neutrinos, leading to upper limits on the extraterrestrial neutrino flux measured at the earth. For an assumed E-2 spectrum, a 90% classical confidence level upper limit has been placed at a level E2Phi(E)=8.4 x 10(-7) cm(-2) s(-1) sr(-1) GeV (for a predominant neutrino energy range 6-1000 TeV), which is the most restrictive bound placed by any neutrino detector. Some specific predicted model spectra are excluded. Interpreting these limits in terms of the flux from a cosmological distributions of sources requires the incorporation of neutrino oscillations, typically weakening the limits by a factor of 2.

Journal Article↗

An in situ study of metal complexation by an immobilized synthetic biopolymer using tapping mode liquid cell atomic force microscopy.

Near-field scanning optical microscopy and tapping mode, liquid cell atomic force microscopy were used to study the conformational changes in simple short-chain silica-immobilized biopolymer, poly(L-cysteine) (PLCys), as the polymer was exposed to reducing, metal-rich, and acidic environments, respectively, to simulate on-line metal preconcentration. In a reducing environment (0.01 M dithiothreitol in pH 7.0 ammonium acetate buffer), the PLCys features resembled islands on the surface of the glass, 36 +/- 7 nm in height and 251 +/- 60 nm in diameter. Upon exposure to metal (Cd2+ buffered at pH 7.0), the PLCys islands broke up into smaller metal binding clusters whose features were lower in height, 22 +/- 5 nm, and diameter, 213 +/- 53 nm. Exposure to 0.01 M HCl used for metal stripping resulted in protonation of the polymer chains and further reduction in the polymer height to 12 +/- 5 nm. These changes in molecular structure have given new insight into the mechanisms involved to achieve strong binding as well as rapid, quantitative release of bound metals to flexible short-chain synthetic biopolymers.

Biopolymers↗

Comparison and evaluation of the synthetic biopolymer poly-L-aspartic acid and the synthetic "plastic" polymer poly-acrylic acid for use in metal ion-exchange systems.

Poly-L-aspartic acid (PLAsp), a biopolymer, and a similar synthetic polymer, poly-acrylic acid (PAA), each consisting of approximately 50 repeating Asp and acrylic acid monomers, respectively, were immobilized onto controlled pore glass (CPG) and evaluated for use as metal ion-exchange materials. Both polymers achieve metal complexation primarily through their repeating carboxylate side groups resulting in a similar binding trend for the metals tested (Ca(2+), Cd(2+), Co(2+), Cu(2+), Mg(2+), Mn(2+), Na(+), Ni(2+), Pb(2+)), with metal binding capacities ranging from <0.1 to 12 micromol metal/g column and <0.1 to 32 micromol metal/g column for PLAsp and PAA respectively. Cu(2+) and Pb(2+) exhibited strong binding to both materials, while the other metals demonstrated only weak or minimal binding. Both columns allowed for quantitative release of bound metals through acid stripping and experienced increased overall metal binding with increasing pH. Both systems also maintained similar structural and chemical stability when continuously exposed to neutral buffered, highly acidic, oxidizing, large molecule rich, and elevated temperature environments. The main differences between the two systems are the material cost and system biodegradability.

Acrylates↗

Observation of high-energy neutrinos using Cerenkov detectors embedded deep in Antarctic ice.

Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water or ice. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations.

Journal Article↗

[Effect of modern instrumental diagnosis on surgical indications for resection of colorectal liver metastases].

In order to select those patients with colorectal liver metastases who may have benefit from an operation, preoperative detection and localization of tumors in the liver is necessary. In this study, the specificity and sensitivity of a CT arterial portography and magnetic resonance imaging with contrast media was compared with the results of operative findings and intraoperative ultrasonography. The combination of both preoperative methods led to an accuracy rate of more than 90%, and all patients who underwent laparotomy were resected or treated with an arterial infusion port system. Negative laparotomies were excluded completely.

Colorectal Neoplasms↗

Symptomatic intracranial hemorrhage in full-term infants.

A retrospective analysis was undertaken in a consecutive series of 33 full-term infants (birth weight > 2500 g and a minimum of 37 weeks gestational age) with symptomatic intracranial hemorrhage (ICH) admitted to a regional neonatal intensive care unit from January 1986 to December 1992. Eleven infants were born in our institution; 17 were male. The estimated local incidence of symptomatic ICH for the inborn population was 4.9/10000 live births, with a regional incidence of 2.7/10000 live births. Twenty-four (72.3%) infants presented with seizures, apnea, or respiratory distress. Five (15.1%) children developed ICH associated with extracorporeal membrane oxygenation, ventriculoperitoneal shunting, and cardiac surgery. There were two deaths (6.1%) associated with a grade IV periventricular hemorrhage (PVH) and cardiac surgery. Nine infants (27.3%) showed PVH, while an additional nine children developed multifocal cortical hemorrhages. Eight infants (24.2%) showed extra-axial ICH, four children (12.1%) sustained lobar hemorrhages, and three children (9.1%) showed ICH associated with prenatal CNS abnormalities. Excluding five children with iatrogenic ICH, coagulopathies occurred in 9 of 28 infants (32.1%) and constituted a major determinant of the development of ICH. Neurosurgical intervention was limited to one infant with massive ICH and one child with hydrocephalus as a late sequela of ICH. Developmental follow-up was complete in 32 children with a mean and median duration of 3.4 years. Full-term infants with ICH associated with risk factors for hypoxic-ischemic injury showed a significantly greater risk of developmental delay compared to infants with uncomplicated ICH.

Cerebral Hemorrhage↗

Lobar hemorrhages in full-term neonates.

A chart analysis for a 5-year period through December 1992 identified four full-term neonates with lobar hemorrhage. Prenatal and obstetrical histories were uncomplicated; all infants presented with seizures within 48 h following birth. Perinatal asphyxia and isoimmune thrombocytopenia were associated with lobar hemorrhage in two children. Although computed tomography was sufficient for diagnosis, magnetic resonance evaluation provided assessment of specific cortical injury and the age of the hemorrhage. No infant underwent surgical intervention; three children reached developmental milestones at a mean follow-up of 3.3 years.

Brain↗

Office care of the small, premature infant.

About 1% of infants are born before 32 weeks of pregnancy, and 0.9% have a birthweight of 1500 gm or less. More of these premature infants are surviving. Contributing factors include prenatal corticosteroid therapy and early surfactant therapy to reduce the incidence of respiratory distress syndrome. Because of this, more family physicians are providing office care for premature infants after discharge from neonatal intensive care centers. These infants require special care in the office as well as the neonatal intensive care unit. The goal of the family physician's care should be to minimize mortality and morbidity. This article summarizes recommendations for office care of the surviving premature infant.

Developmental Disabilities↗

Incidence and neurodevelopmental outcome of periventricular hemorrhage and hydrocephalus in a regional population of very low birth weight infants.

During the years 1984 to 1987, 459 very low birth weight (VLBW) infants were admitted to a state-designated Level III Neonatal Intensive Care Unit. Cerebral sonography performed in a standardized sequence and graded with the Papile scale diagnosed 97 (21.1%) children with periventricular hemorrhage (PVH). The incidence of PVH declined from a peak of 26.6% in 1985 to 16.4% in 1987, associated with an increase in the incidence of inborn admissions (including maternal transport) from 62.0% in 1984 to 80.4% in 1987. During initial hospitalization, the occurrence of both low-grade (Grades I and II) and high-grade PVH was associated with a significantly higher incidence of perinatal risk factors compared with a concurrent population of VLBW infants without PVH. Developmental follow-up was achieved in 93.3% of VLBW infants without PVH and 95.7% of VLBW infants with PVH who survived their initial hospitalization. The incidence of abnormal outcome ranged from 7 of 37 infants with Grade I PVH to 7 of 8 VLBW infants with Grade IV PVH. Only 1 of 16 VLBW infants with high-grade PVH demonstrated normal motor and cognitive development. Active hydrocephalus developed in 12 infants; 11 sustained a high-grade PVH. Appropriate treatment of intracranial hypertension did not modify the neurodevelopmental outcome. In conclusion, this regional population of VLBW infants demonstrated a decline in the incidence of PVH during the years 1984 to 1987 associated with an increase in the incidence of inborn admissions. The risk of abnormal neurodevelopmental outcome was elevated for all grades of PVH. A 12.0% incidence of hydrocephalus was associated with high-grade PVH, and appropriate treatment did not alter the poor prognosis.

Cerebral Hemorrhage↗

[Severe liver involvement by Capillaria hepatica].

Human hepatic capillariasis is a rare disease, which predominantly affects children aged 1 to 4 years and has a poor prognosis in extensive infections. This is the first case observed in Germany. The main symptoms are those of severe parasitosis: persistent high fever, hepatomegaly, and excessive hypereosinophilia. Diagnosis is confirmed by the finding of intracellular typical eggs in liver biopsy. There is a lack of established therapy; our 18 months old girl developed liver fibrosis. She survived under a prolonged treatment with high doses of Thiabendazole and two single doses of Ivermectine. Decortin was given to inhibit further granulomatous processes in the liver.

Animals↗

A history of regionalized premature care in rural Illinois.

Many historical accounts have been published on the development of premature infant care. Almost exclusively, these descriptions have involved large urban centers with university affiliation. A large rural health care region has never received comparable historical perspective. Public health records, official medical society publications, and local community hospital documents and interviews are collated in order to recreate the evolution of regionalized premature care in rural Illinois.

Child Health Services↗

Office care of the premature infant.

The family physician should follow the small premature infant in the neonatal intensive care center and review the baby's problems and risk factors. In the office, special attention is required in monitoring the infant. Proper hospital and office care greatly improve the prognosis.

Anemia↗

Diagnosis of subdural hemorrhage in utero. Case report.

A case is presented of subdural hemorrhage diagnosed in utero at 31 weeks of gestation by fetal ultrasonography. Following delivery, clinical examination of the infant revealed hydrops fetalis, right-sided cardiomegaly, hepatic dysfunction, and coagulopathy. Prompt resolution of these problems led to a retrospective diagnosis of premature closure of the foramen ovale as the precipitating event. The causes of previously reported cases of intrauterine cerebral hemorrhage are reviewed and compared to the present case.

Adult↗

Maternal transport and the perinatal denominator.

In conjunction with an active outreach program, a rural perinatal region of 18,000 deliveries was analyzed. All pregnancies which resulted in the delivery of live-born infants weighing 1,000 to 1,500 gm were reviewed for maternal/fetal risk and eventual neonatal outcome. Analysis included all mothers and infants cared for at regional hospitals as well as those transferred to any tertiary care center in the state system. Thus, an entire "perinatal denominator" for this group of patients at very high risk was identified. Maternal/fetal risk scoring was highest for the group of mothers transferred to the tertiary center prior to delivery. In spite of this increased risk, infant mortality was significantly decreased by delivery at the tertiary care center. It is recommended that other groups of high-risk conditions be evaluated in regional systems only after the entire perinatal denominator has been identified.

Female↗