Spatially Resolved Raman Spectroscopic Investigation of Uranyl Fluoride: A Case Study in the Importance of Instrument Optimization.

Raman spectroscopy is an emerging technique for rapid and nondestructive analysis of nuclear materials for forensic and nonproliferation applications as it is a powerful tool for distinguishing multiple chemical forms of materials with similar stoichiometries. Recent developments in spectroscopic software have enabled rapid data collection with high-speed Raman spectroscopic mapping capabilities. However, some uranium-rich materials are susceptible to degradation in humid air and/or laser-induced phase transformations. To mitigate environmental or measurement-related sample degradation of potential samples of interest, we have taken a systematic approach to define optimized data collection parameters for high-throughput measurements of uranyl fluoride (UO2F2), which is an important intermediate material in the nuclear fuel cycle. First, we systematically describe the influence of optical magnification (5× to 100×), laser power, and exposure time on obtained signal for identical particles of UO2F2 and find that at low laser power and exposure times, comparable signal is obtained regardless of optical magnification. Second, we ensure sample integrity during data collection, and third, collect spectroscopic maps that employ optimized parameters to reduce the time required to obtain spatially resolved spectroscopic information. Reductions of 90% and 99% in measurement times are discussed as they relate to differences in resolving spectroscopic features of particles in identical mapping areas. During this work, we found that additional data processing options were needed and thus developed a customized Python script for importing, processing, analyzing, and visualizing Raman spectroscopic map data.

Identification of Uranium Minerals in Natural U-Bearing Rocks Using Infrared Reflectance Spectroscopy.

The identification of minerals, including uranium-bearing species, is often a labor-intensive process using X-ray diffraction (XRD), fluorescence, or other solid-phase or wet chemical techniques. While handheld XRD and fluorescence instruments can aid in field applications, handheld infrared (IR) reflectance spectrometers can now also be used in industrial or field environments, with rapid, nondestructive identification possible via analysis of the solid's reflectance spectrum providing information not found in other techniques. In this paper, we report the use of laboratory methods that measure the IR hemispherical reflectance of solids using an integrating sphere and have applied it to the identification of mineral mixtures (i.e., rocks), with widely varying percentages of uranium mineral content. We then apply classical least squares (CLS) and multivariate curve resolution (MCR) methods to better discriminate the minerals (along with two pure uranium chemicals U3O8 and UO2) against many common natural and anthropogenic background materials (e.g., silica sand, asphalt, calcite, K-feldspar) with good success. Ground truth as to mineral content was attained primarily by XRD. Identification is facile and specific, both for samples that are pure or are partially composed of uranium (e.g., boltwoodite, tyuyamunite, etc.) or non-uranium minerals. The characteristic IR bands generate unique (or class-specific) bands, typically arising from similar chemical moieties or functional groups in the minerals: uranyls, phosphates, silicates, etc. In some cases, the chemical groups that provide spectral discrimination in the longwave IR reflectance by generating upward-going (reststrahlen) bands can provide discrimination in the midwave and shortwave IR via downward-going absorption features, i.e., weaker overtone or combination bands arising from the same chemical moieties.

Nouns and verbs in Chintang: children's usage and surrounding adult speech.

Analyzing the development of the noun-to-verb ratio in a longitudinal corpus of four Chintang (Sino-Tibetan) children, we find that up to about age four, children have a significantly higher ratio than adults. Previous cross-linguistic research rules out an explanation of this in terms of a universal noun bias; instead, a likely cause is that Chintang verb morphology is polysynthetic and difficult to learn. This hypothesis is supported by the fact that the development of Chintang children's noun-to-verb ratio correlates significantly with the extent to which they show a similar flexibility with verbal morphology to that of the surrounding adults, as measured by morphological paradigm entropy. While this development levels off around age three, children continue to have a higher overall noun-to-verb ratio than adults. A likely explanation lies in the kinds of activities that children are engaged in and that are almost completely separate from adults' activities in this culture.

Differential tumor-targeting abilities of three single-domain antibody formats.

The large molecular size of antibody drugs is considered one major factor preventing them from becoming more efficient therapeutics. Variable regions of heavy chain antibodies (HCAbs), or single-domain antibodies (sdAbs), are ideal building blocks for smaller antibodies due to their molecular size and enhanced stability. In the search for better antibody formats for in vivo imaging and/or therapy of cancer, three types of sdAb-based molecules directed against epidermal growth factor receptor (EGFR) were constructed, characterized and tested. Eleven sdAbs were isolated from a phage display library constructed from the sdAb repertoire of a llama immunized with a variant of EGFR. A pentameric sdAb, or pentabody, V2C-EG2 was constructed by fusing one of the sdAbs, EG2, to a pentamerization protein domain. A chimeric HCAb (cHCAb), EG2-hFc, was constructed by fusing EG2 to the fragment crystallizable (Fc) of human IgG1. Whereas EG2 and V2C-EG2 localized mainly in the kidneys after i.v. injection, EG2-hFc exhibited excellent tumor accumulation, and this was largely attributed to its long serum half life, which is comparable to that of IgGs. The moderate size (approximately 80 kDa) and intact human Fc make HCAbs a unique antibody format which may outperform whole IgGs as imaging and therapeutic reagents.

[Treatment of an iliac artery pseudoaneurysm managed with a stent graft].

Recent developments have extended the indications for endovascular intervention to include endovascular lesions, such as aneurysms and sclerotic arterioocclusive disease. Although conventional treatment of pseudoaneurysms is mainly surgical intervention, the development of stent grafts has made this treatment less invasive than previously. We placed a stent graft in a pseudoaneurysm of the iliac artery with good results, as described in this report. Treatment of a pseudoaneurysm with a stent graft avoids the risk associated with general anesthesia and reduces surgical invasiveness, similar to laparotomy. We expect that this therapeutic mode will be developed further in the future.

[Evaluation of 5-FU, leucovorin, etoposide, and cisplatin (FLEP) chemotherapy by hepatic artery injection in the treatment of multiple liver metastases from gastric cancer].

We performed FLEP chemotherapy (consisting of 5-FU, leucovorin, etoposide, and cisplatin) by hepatic artery injections for three patients with multiple liver metastases from gastric cancer, and two of three resulted in partial response (PR). We presented two PR cases. Case 1 is a 57-year-old male with multiple liver metastases from gastric cancer. Distal partial gastrectomy with regional lymphadenectomies were carried out, and an injection port was implanted in the hepatic artery. We performed FLEP chemotherapy from 16 days after the operation. Liver metastases subsided and resulted in PR after 3 months by CT scan. He is now healthy and working for 15 months after the operation. Case 2 was a 49-year-old female with multiple liver metastases from gastric cancer. Total gastrectomy with regional lymphadenectomies was carried out. We performed FLEP chemotherapy by hepatic artery injections from 21 days after the operation. The response of chemotherapy resulted in PR by CT scan, and she is now healthy and has been working for 11 months after the operation. Thus, this form of chemotherapy may be useful for patients with multiple liver metastases from gastric cancer.

Reorganization of myosin in surface-activated spreading platelets.

To study the localization of myosin in platelets, we utilized polyclonal antibody to heavy chain of platelet myosin. Both immunofluorescence and indirect immunogold staining techniques were employed. (1) In the unactivated platelets, myosin was distributed homogeneously throughout the cytosol. The cytosolic myosin was removed after platelets were treated with Triton X-100. The association of myosin with actin microfilaments in unactivated platelets was minimal. (2) In the surface-activated platelets, myosin was unextractable by Triton X-100. The myosin antibody heavily decorated the actin cable-networks which characterized the activated platelets. (3) In the Triton-unextractable cytoskeleton of both unactivated and activated platelets, we found fine fibrils (about 1-nm wide) that were often associated with immunogolds. These fibrils were similar to purified myosin molecules observed in rotary-shadowed metal replicas and ultrathin sections. These results indicate that cytosolic myosin becomes associated with actin cable-networks after the activation of platelets.

A new antibiotic K-82 A and minor components, produced by Streptomyces lavendulae, strain No. K-82.

From the results of taxonomic studies, Streptomyces sp. strain No. K-82 isolated from a soil sample collected in Kumamoto city, was identified as a strain belonging to Streptomyces lavendulae WAKSMAN & HENRICI 1948. The strain produced an active new antibiotic called K-82 A and minor components named the B complex. Antibiotic K-82 A was isolated as dark reddish needles by silica gel column chromatography and found to have both antibacterial activity and high phage induction activity. The K-82 B complex was found to consist of at least five components, among which K-82 B2 and B3 were isolated as crystals. Substances K-82 B2 was identified as benzoic acid from its physicochemical properties. Substance B3 like B2 had only marginal antibiotic activity.