Electrochemical studies of octadecanethiol and octanethiol films on variable surface area mercury sessile drops

Octadecanethiol (ODT) and octanethiol (OT) films at the mercury-electrolyte interface are examined using cyclic voltammetry and differential capacitance measurements at a single frequency. A mercury flow-system is used to alter the volume, and therefore, the surface area and surface pressure of the mercury electrode. Manipulation of the mercury electrode's volume enables the introduction and removal of defects in the insulating thiol films. OT and ODT film behavior are contrasted under conditions of expansion and contraction. ODT forms extremely impermeable layers that allow 1000 time less redox probe current than seen on uncoated drops. Expansion of the mercury electrode to increase the electrode surface area produces defects and pinholes in the thiol film. These defects are almost completely removed when the drop is compressed back to its initial surface area. OT also forms insulating films on mercury sessile drops, however these films contain more defects than ODT films. While expansion of an OT-coated mercury drop increases redox probe current, recompression of the drop does not return the film to its initial condition. Pinholes and defects in the OT and ODT films can also be produced by cycling to negative potentials, which produce abrupt stripping peaks.     

REVISE: A Tool for Measuring and Mitigating Bias in Visual Datasets

International Journal of Computer Vision - Machine learning models are known to perpetuate and even amplify the biases present in the data. However, these data biases frequently do not become...     

Feedstock powder processing research needs for additive manufacturing development

Additive manufacturing (AM) promises to redesign traditional manufacturing by enabling the ultimate in agility for rapid component design changes in commercial products and for fabricating complex integrated parts. By significantly increasing quality and yield of metallic alloy powders, the pace for design, development, and deployment of the most promising AM approaches can be greatly accelerated, resulting in rapid commercialization of these advanced manufacturing methods. By successful completion of a critical suite of processing research tasks that are intended to greatly enhance gas atomized powder quality and the precision and efficiency of powder production, researchers can help promote continued rapid growth of AM. Other powder-based or spray-based advanced manufacturing methods could also benefit from these research outcomes, promoting the next wave of sustainable manufacturing technologies for conventional and advanced materials.     

Differences in Epstein-Barr virus expression between primary and secondary cutaneous angiocentric lymphomas. French Study Group of Cutaneous Lymphomas

OBJECTIVE: The aim of this investigation was to report on the radiographic interpretation of the hard palate and nasal fossa floor in panoramic radiographs by studying different skulls, x-ray machines, and head positions in relationship to the Frankfort plane before and after ostectomy. STUDY DESIGN: Twenty dry human skulls were radiographed with three different panoramic x-ray machines in three different positions. Three of the skulls were submitted to different ostectomies. RESULTS: Multiple images of the hard palate and nasal fossa floor were present in 96.12% of the radiographs. Single images (3.88%) occurred only in the "chin up" position. CONCLUSIONS: The lower image represents the nasal fossa floor, especially its lateral and anterior limits. The upper images are double real images mainly formed by the junction of the nasal septum with the nasal fossa floor and possibly by posterior parts of the hard palate and nasal fossa floor. All images overlap in the "chin up" position becoming a single image. The most common shape of the anatomic landmark was wide angle "W" (58.33%). Other shapes present in positions "chin up" and "chin down" indicate patient positioning errors. The x-ray machines did not influence the results.     

Congenital fibrosis of the extraocular muscles type 2, an inherited exotropic strabismus fixus, maps to distal 11q13

The extraocular fibrosis syndromes are congenital ocular-motility disorders that arise from dysfunction of the oculomotor, trochlear, and abducens nerves and/or the muscles that they innervate. Each is marked by a specific form of restrictive paralytic ophthalmoplegia with or without ptosis. Individuals with the classic form of congenital fibrosis of the extraocular muscles (CFEOM1) are born with bilateral ptosis and a restrictive infraductive external ophthalmoplegia. We previously demonstrated that CFEOM1 is caused by an autosomal dominant locus on chromosome 12 and results from a developmental absence of the superior division of the oculomotor nerve. We now have mapped a variant of CFEOM, exotropic strabismus fixus ("CFEOM2"). Affected individuals are born with bilateral ptosis and restrictive ophthalmoplegia with the globes "frozen" in extreme abduction. This autosomal recessive disorder is present in members of three consanguineous Saudi Arabian families. Genetic analysis of 70 individuals (20 affected individuals) reveals linkage to markers on chromosome 11q13, with a combined LOD score of 12.3 at the single nonrecombinant marker, D11S1314. The 2.5-cM CFEOM2 critical region is flanked by D11S4196/D11S4162 and D11S4184/1369. Two of the three families share a common disease-associated haplotype, suggesting a founder effect for CFEOM2. We hypothesize that CFEOM2 results from an analogous developmental defect to CFEOM1, one that affects both the superior and inferior divisions of the oculomotor nerve and their corresponding alpha motoneurons and extraocular muscles.     

Purification and properties of beta-N-Acetylhexosaminidase from cabbage

beta-N-Acetylhexosaminidase was purified from the extract of cabbage by sequential steps of ammonium sulfate fractionation, chromatofocusing, DEAE-Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 HR gel filtration. By these steps, the purity of the enzyme increased by 256 fold with a recovery of 8%. The purified enzyme was homogeneous as examined by native PAGE. It showed an optimal pH of 4, an optimal temperature of 60 degrees C and a Km of 0.94 mM for hydrolysis of pNp-beta-GlcNAc. The molecular mass of the enzyme determined from filtration through Sephacryl S-200 was 150 kDa. Three subunits with molecular mass of 64, 57 and 51 kDa were observed as determined by SDS-PAGE. NBS (0.025 mM), DEPC (3 mM) and WRK (30 mM) significantly inhibited the activity of the enzyme. The enzyme also showed activity toward pNp-beta-GalNAc, N,N'-diacetylchitobiose, N,N',N"-triacetylchitotriose and N,N',N",N"'-tetraacetyl chitotetraose but showed no activity toward pNp-alpha-GlcNAc, chitin and ethylene glycol chitin.     

Radiotherapy of plantar heel spurs: indications, technique, clinical results at different dose concepts

BACKGROUND: In a retrospective study the efficacy of orthovoltage radiotherapy for refractory painful plantar heel spur was analyzed for 3 different radiation dose concepts. PATIENTS AND METHODS: From 1.1 1984 through 1.3.1994, 182 patients with refractory painful heel symptoms and radiologically proven plantar heel spur received radiotherapy. A total of 141 patients and 170 heels (due to double-sided symptoms) were completely documented in long-term follow-up. Clearly defined semi-quantitative criteria (9-point score) were used to analyze heel pain and ankle function prior to RT, 6 to 12 weeks post-radiation, and at last follow-up. The treatment outcome, i.e. (un)favourable response, of 3 radiation dose concepts were compared: Group A (n = 72 heels) received 12 Gy total radiation dose in 3 fractions per week and 2 series (6 x 1 Gy per series) separated by 6 weeks; group B (n = 98 heels) received 3 Gy total radiation dose in 10 fractions of 0.3 Gy (n = 50) or 5 Gy (10 x 0.5 Gy) (n = 48) with conventional fractionation in 1 series. RESULTS: Radiotherapy was very effective: at last follow-up 67% (group A) and 71% (group B) remained completely free of pain. The rate of "complete pain relief" (i.e. free of any pain symptoms) was not different between the 3 radiation concepts. However, significant differences were observed with regard to "incomplete or insufficient pain relief", i.e. a subjective pain relief of less than 80%, a delayed pain relief after more than 4 weeks or a relapse of pain symptoms in long-term follow-up. More favourable results were achieved in patients receiving 5 Gy or 12 Gy total dose, while patients with 3 Gy total dose had significantly worse results. Prognostic factors for "complete pain relief" were short duration of pain symptoms and acute pain symptoms prior to radiotherapy; with regard to "in-complete or insufficient pain relief" the total dose was found to be a prognostic parameter. CONCLUSIONS: Patients with refractory heel pain can yield a high response to radiotherapy even after failing various conventional treatments previously. Thus, radiotherapy should not be solely regarded as a last resort due to its low costs and high efficacy at low radiation doses.