353 research outputs found
Spectrographic analysis of bismuth-tin eutectic alloys by spark-ignited low-voltage ac-arc excitation
Spectrographic method determines individual stainless steel components in molten bismuth-42 w/o tin eutectic to determine the solubility of Type 304 stainless steels. It utilizes the high sensitivity and precision of the spark-ignited, low-voltage ac-arc excitation of samples rendered homogeneous by dissolution
Advantages and limitations of virtual reality for balance assessment and rehabilitation
International audienceVirtual reality (VR) is now commonly used in many domains because of its ability to provide a standardized, reproducible and controllable environment. In balance assessment, it can be used to control stimuli presented to patients and thus accurately evaluate their progression or compare them to different populations in standardized situations. In balance rehabilitation, VR allows the creation of new generation tools and at the same time the means to assess the efficiency of each parameter of these tools in order to optimize them. Moreover, with the development of low-cost devices, this rehabilitation can be continued at home, making access to these tools much easier, in addition to their entertaining and thus motivating properties. Nevertheless, and even more with low-cost systems, VR has limits that can alter the results of the studies that use it: the latency of the system (the delay cumulated on each step of the process from data acquisition on the patients to multimodal outputs); and distance perception, which tends to be underestimated in VR. After having described why VR is an essential tool for balance assessment and rehabilitation and illustrated this statement with a case study, this review discusses the previous works in the domain with regards to the technological limits of V
Treatment of patients with distant metastases from phyllodes tumor of the breast
BACKGROUND: Here, the treatment methods and results of patients with phyllodes tumor of the breast (PT) with distant metastases at a single institution are presented. METHODS: A retrospective analysis was performed on a group of 295 patients with PT treated from 1952 to 2010. RESULTS: Distant metastases developed in 37 (12.5 %) patients; 3/160 (1.9 %) patients had benign PT, 6/36 (16.7 %) were considered borderline, and 28/99 (28.3 %) had malignant PT. Most frequently, the metastases were located in the lungs; 28 (75.7 %), bone 7 (18.9 %), brain 4 (10.8 %), and liver 2 (5.4 %). Metastases occurred on overage 21 months (2–57) after surgery. Patients with lung metastases were generally treated with monochemotherapy or polychemotherapy. In one patient Testosterone and in two patients resection of metastases combined with Doxorubicin were used. Patients with bones or brain metastases were treated with palliative radiotherapy only or combined with Doxorubicin. The mean survival (MS) from diagnosis of distant metastases (DM) was 7 months (2–17). The longest mean survival in patients with bones metastases was 11.8 months, the worst survival was for patients with brain metastases—2.8 months. Hormone therapy appeared to have low efficacy (MS: 2 months) as well as monochemotherapy (MS: 3–5 months). Improved MS was obtained using Doxorubicin (7 months) and Doxorubicin with Cisplatin, Cyclophosphamide, or Ifosfamide (9 months). CONCLUSION: The prognosis of patients with DM from PT is poor. The role of surgery and irradiation of such patients is very limited. There appears to be no role for the use of hormone therapy. This study showed that polychemotherapy with Doxorubicin and Ifosfamide suggest that it might be more effective than once thought
Realistic following behaviors for crowd simulation
International audienceWhile walking through a crowd, a pedestrian experiences a large number of interactions with his neighbors. The nature of these interactions is varied, and it has been observed that macroscopic phenomena emerge from the combination of these local interactions. Crowd models have hitherto considered collision avoidance as the unique type of interactions between individuals, few have considered walking in groups. By contrast, our paper focuses on interactions due to the following behaviors of pedestrians. Following is frequently observed when people walk in corridors or when they queue. Typical macroscopic stop-and-go waves emerge under such traffic conditions. Our contributions are, first, an experimental study on following behaviors, second, a numerical model for simulating such interactions, and third, its calibration, evaluation and applications. Through an experimental approach, we elaborate and calibrate a model from microscopic analysis of real kinematics data collected during experiments. We carefully evaluate our model both at the microscopic and the macroscopic levels. We also demonstrate our approach on applications where following interactions are prominent
Eta-mesic nuclei in relativistic mean-field theory
With the eta-nucleon (eta N) interaction Lagrangian deduced from chiral
perturbation theory, we study the possible eta-mesic nuclei in the framework of
relativistic mean-field theory. The eta single-particle energies are sensitive
to the eta N scattering length, and increase monotonically with the nucleon
number A. If the scattering length is in the range of a^{eta N}=0.75-1.05 fm
and the imaginary potential V_{0}-15 MeV, some discrete states of C, O and Ne
eta bound states should be identified in experiments. However, when the
scattering length a^{eta N} 30 MeV,
no discrete eta meson bound states could be observed in experiments.Comment: 6 page
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Effector memory differentiation increases detection of replication-competent HIV-l in resting CD4+ T cells from virally suppressed individuals.
Studies have demonstrated that intensive ART alone is not capable of eradicating HIV-1, as the virus rebounds within a few weeks upon treatment interruption. Viral rebound may be induced from several cellular subsets; however, the majority of proviral DNA has been found in antigen experienced resting CD4+ T cells. To achieve a cure for HIV-1, eradication strategies depend upon both understanding mechanisms that drive HIV-1 persistence as well as sensitive assays to measure the frequency of infected cells after therapeutic interventions. Assays such as the quantitative viral outgrowth assay (QVOA) measure HIV-1 persistence during ART by ex vivo activation of resting CD4+ T cells to induce latency reversal; however, recent studies have shown that only a fraction of replication-competent viruses are inducible by primary mitogen stimulation. Previous studies have shown a correlation between the acquisition of effector memory phenotype and HIV-1 latency reversal in quiescent CD4+ T cell subsets that harbor the reservoir. Here, we apply our mechanistic understanding that differentiation into effector memory CD4+ T cells more effectively promotes HIV-1 latency reversal to significantly improve proviral measurements in the QVOA, termed differentiation QVOA (dQVOA), which reveals a significantly higher frequency of the inducible HIV-1 replication-competent reservoir in resting CD4+ T cells
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