808 research outputs found
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A novel design process of low cost 3D printed ambidextrous finger designed for an ambidextrous robotic hand
This paper presents the novel mechanical design of an ambidextrous finger specifically designed for an ambidextrous anthropomorphic robotic hand actuated by pneumatic artificial muscles. The ambidextrous nature of design allows fingers to perform both left and right hand movements. The aim of our design is to reduce the number of actuators, increase the range of movements with best possible range ideally greater than a common human finger. Four prototypes are discussed in this paper; first prototype is focused on the choice of material and to consider the possible ways to reduce friction. Second prototype is designed to investigate the tendons routing configurations. Aim of third and fourth prototype is to improve the overall performance and to maximize the grasping force. Finally, a unified design (Final design) is presented in great detail. Comparison of all prototypes is done from different angles to evaluate the best design. The kinematic features of intermediate mode have been analysed to optimize both the flexibility and the robustness of the system, as well as to minimize the number of pneumatic muscles. The final design of an ambidextrous finger has developed, tested and 3D printed
Survival of bacterial isolates exposed to simulated Jovian trapped radiation belt electrons and solar wind protons
With missions to Jupiter, the spacecraft will be exposed for extended duration to solar wind radiation and the Jovian trapped radiation belt. This study is designed to determine the effect of these radiation environments on spacecraft bacterial isolates. The information can be used in the probability of contamination analysis for these missions. A bacterial subpopulation from Mariner Mars 1971 spacecraft (nine sporeforming and three nonsporeforming isolates) plus two comparative organisms, Staphylococcus epidermidis ATCC 17917 and a strain of Bacillus subtilis var. niger, were exposed to 2-, 12-, and 25-MeV electrons at different doses with simultaneous exposure to a vacuum of 0.0013 N/sqm at 20 and -20 C. The radioresistance of the subpopulation was dependent on the isolate, dose, and energy of electrons. Temperature affected the radioresistance of only the sporeforming isolates. Survival data indicated that spores were reduced approximately 1 log/1500 J/kg, while nonsporeforming isolates (micrococci) were reduced 1.5 to 2 logs/1500 J/kg with the exception of an apparent radioresistant isolate whose resistance approached that of the spores. The subpopulation was found to be less resistant to lower energy than to higher energy electrons
Activated lymphocyte recruitment into the tumor microenvironment following preoperative sipuleucel-T for localized prostate cancer.
BackgroundSipuleucel-T is a US Food and Drug Administration-approved immunotherapy for asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC). Its mechanism of action is not fully understood. This prospective trial evaluated the direct immune effects of systemically administered sipuleucel-T on prostatic cancer tissue in the preoperative setting.MethodsPatients with untreated localized prostate cancer were treated on an open-label Phase II study of sipuleucel-T prior to planned radical prostatectomy (RP). Immune infiltrates in RP specimens (posttreatment) and in paired pretreatment biopsies were evaluated by immunohistochemistry (IHC). Correlations between circulating immune response and IHC were assessed using Spearman rank order.ResultsOf the 42 enrolled patients, 37 were evaluable. Adverse events were primarily transient, mild-to-moderate and infusion related. Patients developed T cell proliferation and interferon-γ responses detectable in the blood following treatment. Furthermore, a greater-than-three-fold increase in infiltrating CD3(+), CD4(+) FOXP3(-), and CD8(+) T cells was observed in the RP tissues compared with the pretreatment biopsy (binomial proportions: all P < .001). This level of T cell infiltration was observed at the tumor interface, and was not seen in a control group consisting of 12 concurrent patients who did not receive any neoadjuvant treatment prior to RP. The majority of infiltrating T cells were PD-1(+) and Ki-67(+), consistent with activated T cells. Importantly, the magnitude of the circulating immune response did not directly correlate with T cell infiltration within the prostate based upon Spearman's rank order correlation.ConclusionsThis study is the first to demonstrate a local immune effect from the administration of sipuleucel-T. Neoadjuvant sipuleucel-T elicits both a systemic antigen-specific T cell response and the recruitment of activated effector T cells into the prostate tumor microenvironment
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Cereal Leaf Beetle: Identification, Control, and California Quarantine Alert
Provides distribution, host-plant, life history, habits, signs of damage, and identification information for the cereal leaf beetle, first found in Oregon in 1999. Discusses methods of chemical and biological control. Includes information on California's quarantine on agricultural products from Oregon and four color photographs of the cereal leaf beetle and damaged plants
Correlation of High-Risk Soft Tissue Sarcoma Biomarker Expression Patterns with Outcome following Neoadjuvant Chemoradiation
© 2018 John M. Kane III et al. Background. Sarcoma mortality remains high despite adjuvant chemotherapy. Biomarker predictors of treatment response and outcome could improve treatment selection. Methods. Tissue microarrays (TMAs) were created using pre- and posttreatment tumor from two prospective trials (MGH pilot and RTOG 9514) of neoadjuvant/adjuvant MAID chemotherapy and preoperative radiation. Biomarkers were measured using automated computerized imaging (AQUA or ACIS). Expression was correlated with disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS). Results. Specimens from 60 patients included 23 pretreatment (PRE), 40 posttreatment (POST), and 12 matched pairs (MPs). In the MP set, CAIX, GLUT1, and PARP1 expression significantly decreased following neoadjuvant therapy, but p53 nuclear/cytoplasmic (N/C) ratio increased. In the PRE set, no biomarker expression was associated with DFS, DDFS, or OS. In the POST set, increased p53 N/C ratio was associated with a significantly decreased DFS and DDFS (HR 4.13, p=0.017; HR 4.16, p=0.016), while increased ERCC1 and XPF expression were associated with an improved DFS and DDFS. No POST biomarkers were associated with OS. Conclusions. PRE biomarker expression did not predict survival outcomes. Expression pattern changes after neoadjuvant chemoradiation supports the concepts of tumor reoxygenation, altered HIF-1α signaling, and a p53 nuclear accumulation DNA damage response. Clinical Trial Registration. NRG Oncology RTOG 9514 is registered with ClinicalTrials.gov. The ClinicalTrials.gov Identifier is NCT00002791
Development and pilot evaluation of a personalized decision support intervention for low risk prostate cancer patients.
ObjectivesDevelopment and pilot evaluation of a personalized decision support intervention to help men with early-stage prostate cancer choose among active surveillance, surgery, and radiation.MethodsWe developed a decision aid featuring long-term survival and side effects data, based on focus group input and stakeholder endorsement. We trained premedical students to administer the intervention to newly diagnosed men with low-risk prostate cancer seen at the University of California, San Francisco. Before the intervention, and after the consultation with a urologist, we administered the Decision Quality Instrument for Prostate Cancer (DQI-PC). We hypothesized increases in two knowledge items from the DQI-PC: How many men diagnosed with early-stage prostate cancer will eventually die of prostate cancer? How much would waiting 3 months to make a treatment decision affect chances of survival? Correct answers were: "Most will die of something else" and "A little or not at all."ResultsThe development phase involved 6 patients, 1 family member, 2 physicians, and 5 other health care providers. In our pilot test, 57 men consented, and 44 received the decision support intervention and completed knowledge surveys at both timepoints. Regarding the two knowledge items of interest, before the intervention, 35/56 (63%) answered both correctly, compared to 36/44 (82%) after the medical consultation (P = .04 by chi-square test).ConclusionsThe intervention was associated with increased patient knowledge. Data from this pilot have guided the development of a larger scale randomized clinical trial to improve decision quality in men with prostate cancer being treated in community settings
Boolean analysis identifies CD38 as a biomarker of aggressive localized prostate cancer.
The introduction of serum Prostate Specific Antigen (PSA) testing nearly 30 years ago has been associated with a significant shift towards localized disease and decreased deaths due to prostate cancer. Recognition that PSA testing has caused over diagnosis and over treatment of prostate cancer has generated considerable controversy over its value, and has spurred efforts to identify prognostic biomarkers to distinguish patients who need treatment from those that can be observed. Recent studies show that cancer is heterogeneous and forms a hierarchy of tumor cell populations. We developed a method of identifying prostate cancer differentiation states related to androgen signaling using Boolean logic. Using gene expression data, we identified two markers, CD38 and ARG2, that group prostate cancer into three differentiation states. Cancers with CD38-, ARG2- expression patterns, corresponding to an undifferentiated state, had significantly lower 10-year recurrence-free survival compared to the most differentiated group (CD38+ARG2+). We carried out immunohistochemical (IHC) staining for these two markers in a single institution (Stanford; n = 234) and multi-institution (Canary; n = 1326) cohorts. IHC staining for CD38 and ARG2 in the Stanford cohort demonstrated that combined expression of CD38 and ARG2 was prognostic. In the Canary cohort, low CD38 protein expression by IHC was significantly associated with recurrence-free survival (RFS), seminal vesicle invasion (SVI), extra-capsular extension (ECE) in univariable analysis. In multivariable analysis, ARG2 and CD38 IHC staining results were not independently associated with RFS, overall survival, or disease-specific survival after adjusting for other factors including SVI, ECE, Gleason score, pre-operative PSA, and surgical margins
Association mapping and marker-assisted selection of the lettuce dieback resistance gene Tvr1
Background: Lettuce (Lactuca saliva L.) is susceptible to dieback, a soilborne disease caused by two
viruses from the family Tombusviridae. Susceptibility to dieback is widespread in romaine and leaf-type
lettuce, while modern iceberg cultivars are resistant to this disease. Resistance in iceberg cultivars is
conferred by Tvr1 - a single, dominant gene that provides durable resistance. This study describes fine
mapping of the resistance gene, analysis of nucleotide polymorphism and linkage disequilibrium in the Tvr1
region, and development of molecular markers for marker-assisted selection.
Results: A combination of classical linkage mapping and association mapping allowed us to pinpoint the
location of the Tvr1 resistance gene on chromosomal linkage group 2. Nine molecular markers, based on
expressed sequence tags (EST), were closely linked to Tvr1 in the mapping population, developed from
crosses between resistant (Salinas and Salinas 88) and susceptible (Valmaine) cultivars. Sequencing of these
markers from a set of 68 cultivars revealed a relatively high level of nucleotide polymorphism (θ = 6.7 ×
10-3) and extensive linkage disequilibrium (r2 = 0.124 at 8 cM) in this region. However, the extent of linkage
disequilibrium was affected by population structure and the values were substantially larger when the
analysis was performed only for romaine (r2 = 0.247) and crisphead (r2 = 0.345) accessions. The association
mapping approach revealed that one of the nine markers (Cntg10192) in the Tvr1 region matched exactly
with resistant and susceptible phenotypes when tested on a set of 200 L. sativa accessions from all
horticultural types of lettuce. The marker-trait association was also confirmed on two accessions of
Lactuca serriola - a wild relative of cultivated lettuce. The combination of three single-nucleotide
polymorphisms (SNPs) at the Cntg10192 marker identified four haplotypes. Three of the haplotypes were
associated with resistance and one of them was always associated with susceptibility to the disease.
Conclusion: We have successfully applied high-resolution DNA melting (HRM) analysis to distinguish all
four haplotypes of the Cntg10192 marker in a single analysis. Marker-assisted selection for dieback
resistance with HRM is now an integral part of our breeding program that is focused on the development
of improved lettuce cultivars
Mixed Supervision of Histopathology Improves Prostate Cancer Classification from MRI
Non-invasive prostate cancer detection from MRI has the potential to
revolutionize patient care by providing early detection of
clinically-significant disease (ISUP grade group >= 2), but has thus far shown
limited positive predictive value. To address this, we present an MRI-based
deep learning method for predicting clinically significant prostate cancer
applicable to a patient population with subsequent ground truth biopsy results
ranging from benign pathology to ISUP grade group~5. Specifically, we
demonstrate that mixed supervision via diverse histopathological ground truth
improves classification performance despite the cost of reduced concordance
with image-based segmentation. That is, where prior approaches have utilized
pathology results as ground truth derived from targeted biopsies and
whole-mount prostatectomy to strongly supervise the localization of clinically
significant cancer, our approach also utilizes weak supervision signals
extracted from nontargeted systematic biopsies with regional localization to
improve overall performance. Our key innovation is performing regression by
distribution rather than simply by value, enabling use of additional pathology
findings traditionally ignored by deep learning strategies. We evaluated our
model on a dataset of 973 (testing n=160) multi-parametric prostate MRI exams
collected at UCSF from 2015-2018 followed by MRI/ultrasound fusion (targeted)
biopsy and systematic (nontargeted) biopsy of the prostate gland, demonstrating
that deep networks trained with mixed supervision of histopathology can
significantly exceed the performance of the Prostate Imaging-Reporting and Data
System (PI-RADS) clinical standard for prostate MRI interpretation
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