This paper presents a comparison study between 10 automatic and six interactive methods for liver segmentation from contrast-enhanced CT images. It is based on results from the "MICCAI 2007 Grand Challenge" workshop, where 16 teams evaluated their algorithms on a common database. A collection of 20 clinical images with reference segmentations was provided to train and tune algorithms in advance. Participants were also allowed to use additional proprietary training data for that purpose. All teams then had to apply their methods to 10 test datasets and submit the obtained results. Employed algorithms include statistical shape models, atlas registration, level-sets, graph-cuts and rule-based systems. All results were compared to reference segmentations five error measures that highlight different aspects of segmentation accuracy. All measures were combined according to a specific scoring system relating the obtained values to human expert variability. In general, interactive methods reached higher average scores than automatic approaches and featured a better consistency of segmentation quality. However, the best automatic methods (mainly based on statistical shape models with some additional free deformation) could compete well on the majority of test images. The study provides an insight in performance of different segmentation approaches under real-world conditions and highlights achievements and limitations of current image analysis techniques.

We report the polymerization mechanism and kinetics of muconic esters as the 1,3-diene monomers during solid-state polymerization via a crystal-to-crystal transformation. We have revealed a change in the structure of the muconate crystals accompanying the shrinking and expanding of the lattice lengths, on the basis of the X-ray single-crystal structure analysis of the monomers and polymers as well as a change in the transient structure monitored by powder X-ray diffraction during the continuous X-ray radiation. The polymerization rate is closely related to the molecular stacking distance in the monomer crystals because the polymer chain skeletons have the same conformational structure in the crystals. A lattice length in the direction along which a polymer chain is produced decreases during the transformation from monomer to polymer crystals when monomer molecules are arranged in a columnar assembly with a stacking distance greater than the fiber period of the resulting polymer, and vice versa. A strain in the crystals is formed by a mismatch between the monomer and polymer crystal lattices accumulated and then finally released during the polymerization.

For the solid-state photoisomerization of benzyl (Z,Z)-muconate to the corresponding (E,E)-muconate, the direct observation of a change in the crystal structure has revealed that the isomerization occurs by a topochemical reaction process according to a bicycle-pedal model and is finally accompanied by a phase transition to a stable crystal structure.

A variety of genetic techniques have been devised to determine cell lineage relationships during tissue development. Some of these systems monitor cell lineages spatially and/or temporally without regard to gene expression by the cells, whereas others correlate gene expression with the lineage under study. The GAL4 Technique for Real-time and Clonal Expression (G-TRACE) system allows for rapid, fluorescent protein-based visualization of both current and past GAL4 expression patterns and is therefore amenable to genome-wide expression-based lineage screens. Here we describe the results from such a screen, performed by undergraduate students of the University of California, Los Angeles (UCLA) Undergraduate Research Consortium for Functional Genomics (URCFG) and high school summer scholars as part of a discovery-based education program. The results of the screen, which reveal novel expression-based lineage patterns within the brain, the imaginal disc epithelia, and the hematopoietic lymph gland, have been compiled into the G-TRACE Expression Database (GED), an online resource for use by the Drosophila research community. The impact of this discovery-based research experience on student learning gains was assessed independently and shown to be greater than that of similar programs conducted elsewhere. Furthermore, students participating in the URCFG showed considerably higher STEM retention rates than UCLA STEM students that did not participate in the URCFG, as well as STEM students nationwide.

Antibiotic prescribing practices across the VA experienced significant shifts during the coronavirus (COVID-19) pandemic. From 2015 to 2019, antibiotic use between January – May decreased from 638 to 602 DOT/1000 DP, while the corresponding months in 2020 saw antibiotic utilization rise to 628 DOT/1000 DP.

Background Biomechanical changes in articular cartilage are associated with the onset of osteoarthritis. We developed an optical coherence tomography-based strain rate tomography method: stress relaxation optical coherence straingraphy (SR-OCSA). The purpose of this study was to establish an approach for measuring mechanical properties of articular cartilage using SR-OCSA, and to investigate the distribution of viscoelastic properties of articular cartilage in early osteoarthritis. Methods Anterior cruciate ligament transection surgery was performed on the left knees of 8–9-month-old New Zealand white rabbits. SR-OCSA was used to visualize and measure the viscoelastic properties of articular cartilage via attenuation coefficient of strain rate (ACSR). Using the same conditions as in the SR-OCSA test, an indentation test was conducted, and relaxation time was measured to evaluate the relationship between ACSR and relaxation time. Results SR-OCSA could nondestructively detect and visualize changes in the distribution of viscoelastic properties of articular cartilage in early osteoarthritis. SR-OCSA captured significant increases in ACSR in cartilage at 2 weeks after surgery, when a histologically slight osteoarthritis sign was present. As cartilage degeneration progressed, ACSR increased, whereas relaxation time decreased in a time-dependent manner. Moreover, ACSR negatively correlated with relaxation time. In particular, ACSR was elevated around the tidemark and the elevation tended to move as cartilage degeneration progressed. Conclusions SR-OCSA could tomographically and nondestructively detect and visualize changes in the distribution of viscoelastic properties of articular cartilage in early osteoarthritis. The mechanical properties around the tidemark were degraded as cartilage degeneration progressed. Thus, SR-OCSA provides important data needed to understand the biomechanics of early osteoarthritis.

Abstract. Malignant melanoma is the most aggressive neoplasm, with severe metastatic potential. microRNAs represent a class of endogenously expressed, small non-coding RNAs that regulate gene expression. As a consequence, the translation of these mRNAs is inhibited or they are destabilized resulting in downregulation of the encoded protein.The microRNA-34 (miR-34) family, which comprises three processed microRNAs (miR-34a/b/c) was identified as the mediator of tumor suppression by p53. Many reports suggest that the miR-34s contribute to the inhibition of invasion or metastasis in various tumor types. In this study, we evaluated the expression of the miR-34 family in four human melanoma cell lines (A375, G361, C32TG and SK-MEL-24) which have the wild-type p53 gene using real-time reverse transcription PCR. We also examined their generative and invasive characteristics using the cell proliferation assay and the invasion/ migration assay, respectively. All four melanoma cell lines showed significant expression of miR-34s -A375: miR-34a 0.6176, miR-34b 0.7625, miR-34c 0.7877; G361: 7.6424, 16.4127, 22.0332; C32TG: 2.1630 C32TG: 2. , 2.1091 SK-MEL-24: 0.3621, 2.5659, 8.5907. The cell doubling times of these cell lines in h:min were as follows: A375 23:23, G361 68:24, C32TG 47:22 and SK-MEL-24 67:03. The in vitro generation times of G361 and SK-MEL-24, which showed increased expression of miR-34c, were significantly shorter than A375 with decreased expression of miR-34c (p=0.0063, ANOVA). Invasion (%) of the four cell lines was as follows: A375 44.0%, G361 22.4%, C32TG 13.8% and SK-MEL-24 45.0%. In vitro invasiveness of G361 and C32TG, which showed increased expression of miR-34a, was significantly suppressed (p= 0.005, ANOVA). These results suggest that overexpression of miR-34a and c suppresses invasive and generative potentials, respectively, in human malignant melanoma. IntroductionMalignant melanoma is the most aggressive neoplasm with severe metastatic potential. In recent decades, the incidence of malignant melanoma has steadily increased. A particularly worrying feature of the tumor is its increasing incidence and its capacity for rapid metastatic spread. microRNAs represent a class of endogenously expressed, small non-coding RNAs that regulate gene expression (1,2). As a consequence of translation, these mRNAs are inhibited or destabilized, resulting in downregulation of the encoded protein. A few microRNAs have been classified as oncogenes or tumor-suppressor genes as their expression is altered in tumors, which in some cases has been shown to contribute to the phenotypes of cancer cells. Recently, the microRNA-34 (miR-34) family was identified as the mediator of tumor suppression by p53 (1). Many reports suggest that the miR-34s contribute to inhibition of invasion or metastasis in various tumors. These facts suggest that miR-34s play an important role as inhibitors of tumor growth. However, the biological characteristics of miR-34s in human malignant melanoma are not well understood (3). In this study, w...

Decision-makers need signals for action as the coronavirus disease 2019 (COVID-19) pandemic progresses. Our aim was to demonstrate a novel use of statistical process control to provide timely and interpretable displays of COVID-19 data that inform local mitigation and containment strategies. Healthcare and other industries use statistical process control to study variation and disaggregate data for purposes of understanding behavior of processes and systems and intervening on them. We developed control charts at the county and city/neighborhood level within one state (California) to illustrate their potential value for decision-makers. We found that COVID-19 rates vary by region and subregion, with periods of exponential and non-exponential growth and decline. Such disaggregation provides granularity that decision-makers can use to respond to the pandemic. The annotated time series presentation connects events and policies with observed data that may help mobilize and direct the actions of residents and other stakeholders. Policy-makers and communities require access to relevant, accurate data to respond to the evolving COVID-19 pandemic. Control charts could prove valuable given their potential ease of use and interpretability in real-time decision-making and for communication about the pandemic at a meaningful level for communities.