TolTEC is an upcoming millimeter-wave imaging polarimeter designed to fill the focal plane of the 50-m-diameter Large Millimeter Telescope (LMT). Combined with the LMT, TolTEC will offer ...high-angular-resolution (5
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′
–10
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) simultaneous, polarization-sensitive observations in three wavelength bands: 1.1, 1.4, and 2.0 mm. Additionally, TolTEC will feature mapping speeds greater than
2
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mJy
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, thus enabling wider surveys of large-scale structure, galaxy evolution, and star formation. These improvements are only possible through the integration of approximately 7000 low-noise, high-responsivity superconducting Lumped Element Kinetic Inductance Detectors. Utilizing three focal planes of detector arrays requires the design, fabrication, and characterization of a unique, large-scale cryogenic system. Based on thermal models and expected photon loading, the focal planes must have a base operational temperature below 150 mK. To achieve this base temperature, TolTEC utilizes two cryocoolers, a Cryomech pulse tube cooler and an Oxford Instruments dilution refrigerator, to establish four thermal stages: 45 K, 4 K, 1 K, and 100 mK. During the design phase, we developed an object-oriented Python code to model the heat loading on each stage as well as the thermal gradients throughout the system. This model has allowed us to improve thermal gradients in the system as well as locate areas of poor thermal conductivity prior to ending a cooldown. The results of our model versus measurements from our cooldowns will be presented along with a detailed overview of TolTEC’s cryogenic system. We anticipate TolTEC to be commissioned at the LMT by Spring 2020.
To define the clinical and biochemical abnormalities of an autosomal dominant form of acute encephalopathy.
The clinical details of 11 affected family members in comparison with 63 unaffected ...relatives were analyzed.
Affected children become comatose after onset of a febrile illness. Outcomes include full recovery, permanent neurologic impairment, and death. Recurrences produce more severe impairments. Lesions of necrotizing encephalopathy of the thalamus and brainstem are present on autopsy and MRI. Oxidative phosphorylation of intact mitochondria from a muscle biopsy shows loose coupling. Unaffected family members, including obligate carriers, share no clinical characteristics, demonstrating incomplete penetrance.
Characteristic pathology and MRI findings define this disorder of autosomal dominant acute encephalopathy. Leigh syndrome and sporadic acute necrotizing encephalopathy share similarities but are distinct.
Acute necrotizing encephalopathy (ANE) is a rapidly progressive encephalopathy that can occur in otherwise healthy children after common viral infections such as influenza and parainfluenza. Most ANE ...is sporadic and nonrecurrent (isolated ANE). However, we identified a 7 Mb interval containing a susceptibility locus (ANE1) in a family segregating recurrent ANE as an incompletely penetrant, autosomal-dominant trait. We now report that all affected individuals and obligate carriers in this family are heterozygous for a missense mutation (c.1880C→T, p.Thr585Met) in the gene encoding the nuclear pore protein Ran Binding Protein 2 (RANBP2). To determine whether this mutation is the susceptibility allele, we screened controls and other patients with ANE who are unrelated to the index family. Patients from 9 of 15 additional kindreds with familial or recurrent ANE had the identical mutation. It arose de novo in two families and independently in several other families. Two other patients with familial ANE had different RANBP2 missense mutations that altered conserved residues. None of the three RANBP2 missense mutations were found in 19 patients with isolated ANE or in unaffected controls. We conclude that missense mutations in RANBP2 are susceptibility alleles for familial and recurrent cases of ANE.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In autosomal dominant acute necrotizing encephalopathy (ADANE), apparently healthy children develop necrotizing lesions in their thalami and brainstems in the course of febrile illnesses. We used DNA ...from affected subjects and obligate carriers to map ADANE to a 6.5Mb region on chromosome 2. Sequencing of four candidate genes in the interval (BCL2L11, ST6GalII, CHT1, and FLJ20019), involved in apoptosis, viral recognition, choline transport, and electron transport, showed no disease causing mutations.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Type I spinal muscular atrophy (SMA) is a rapidly progressive, degenerative neuromuscular disease of infancy. In severe SMA, weakness, hypotonia, and bulbar involvement lead to progressive ...respiratory insufficiency and swallowing dysfunction, which are frequently complicated by aspirations. There are few studies reported in the literature that address the respiratory management of type I SMA. This article reports the results of treating four patients with infantile SMA with noninvasive positive pressure ventilation and gastrostomy feeding. All patients had gastroesophageal reflux disease, which was managed medically. Despite these therapies, survival was only 1 to 3.5 months after presenting with severe aspirations. The treatment strategy, which can be effective in less rapidly progressive neuromuscular diseases, did not alter the very poor prognosis of type I SMA. The treatment options are reviewed, and a strategy designed to optimize quality of life for infants with this fatal disease is presented.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Pediatric neuromuscular diseases such as Duchenne muscular dystrophy and spinal muscular atrophy cause pulmonary compromise. In severely affected patients, upper respiratory tract infections ...exacerbate lower respiratory tract secretion retention, with the potential for pneumonia, pulmonary atelectasis, and respiratory failure. In the pediatric intensive care unit, effective treatment includes noninvasive positive pressure ventilation and manual and mechanical mucus clearance techniques. A practical approach to commonly encountered respiratory complications in pediatric neuromuscular diseases is presented in this review.
Noninvasive nasal ventilation is an effective but underutilized method of chronic respiratory support for patients with respiratory insufficiency due to neuromuscular disease. Noninvasive nasal ...ventilation corrects nocturnal hypoxia and hypercapnia, resolving symptoms of chronic alveolar hypoventilation. Noninvasive nasal ventilation can allow selected patients with acute respiratory failure to avoid intubation and it can facilitate endotracheal extubation. Practical guidelines and the rationale for pediatric noninvasive nasal ventilation therapy will be discussed in this review.
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