146 research outputs found
Effect of air core on the shape and discharge of the outflow through a bottom outlet
AbstractExperiments were conducted to study the generation of air core and its effect on the outflow shape and discharge in a cylindrical water tank with a bottom well-designed outlet. Depending on the stages of the air core in the tank, the outflow shape can vary from a smooth water jet to a smooth spindle shape with air-core, and to water sprays. The diameter of the nozzle size also has influence on the outflow pattern. The existence of the penetrated air core can dramatically reduce the outflow discharge, with the discharge coefficient decreasing with the nozzle diameter
Teacher questioning in a Chinese context: Implications for New Zealand classrooms
Teacher questioning is a very important aspect of teacher-student interaction in classrooms around the world. However, expectations of the purposes and types of these interactions can be variable, particularly across cultural contexts. This qualitative study considers the way teacher questioning is used in a mathematics class in a Chinese primary classroom. The types of questions, expectations for answers and teacher behaviours are described through the use of a short-structured observation. Questions were found to be restricted to a rapid-fire format and only a minority of students were called upon to answer questions. This is contrasted with the expectations of the use of questioning in Western contexts, and highlights the challenges for both Chinese teachers and students when they move into the New Zealand education system
Indications for nerve-sparing surgery for radical prostatectomy: Results from a single-center study
PurposeTo explore the clinical indications of using the nerve-sparing technique in radical prostatectomy.Patients and methodsWe retrospectively analyzed the clinical and pathological data of 101 patients who underwent radical prostatectomy (RP) at our institution. Twenty-five patients underwent open surgery, and 76 patients underwent laparoscopic surgery. The biochemical recurrence (BCR) rate was analyzed by the method of Kaplan–Meier. The distance between the ipsilateral neurovascular bundles (NVBs) and foci of prostate tumor (N-T distance) was measured in postoperative specimens. We defined the N-T distance >2 mm as the threshold to perform nerve-sparing (NS) in RP. Through logistic regression analysis, we determined the preoperative clinical indications for the nerve-sparing technique in RP.ResultsThe average BCR-free survival time was 53.2 months in these 101 patients with RP, with the 3- and 5-year BCR-free rates being 87.9% and 85.8%, respectively. The N-T distance was measured in 184 prostate sides from postoperative specimens of 101 patients. Univariate analysis showed that the percent of side-specific biopsy cores with cancer (≥1/3), maximum tumor length in biopsy core (≥5 mm), average percent involvement of each positive core (≥50%), PI-RADS score, and prostate MP-MRI imaging (extra-capsular extension) were associated with the N-T distance (p < 0.003). Furthermore, the percent of side-specific biopsy cores with cancer (≥1/3) (OR = 4.11, p = 0.0047) and prostate MP-MRI imaging (extra-capsular extension) (OR = 3.92, p = 0.0061) were found to be statistically significant independent predictors of the N-T distance in multivariate analysis.ConclusionsThe clinical indications of nerve-sparing RP were <1/3 side-specific biopsy cores with cancer and no extra-capsular extension by prostate MP-MRI examination
Reality3DSketch: Rapid 3D Modeling of Objects from Single Freehand Sketches
The emerging trend of AR/VR places great demands on 3D content. However, most
existing software requires expertise and is difficult for novice users to use.
In this paper, we aim to create sketch-based modeling tools for user-friendly
3D modeling. We introduce Reality3DSketch with a novel application of an
immersive 3D modeling experience, in which a user can capture the surrounding
scene using a monocular RGB camera and can draw a single sketch of an object in
the real-time reconstructed 3D scene. A 3D object is generated and placed in
the desired location, enabled by our novel neural network with the input of a
single sketch. Our neural network can predict the pose of a drawing and can
turn a single sketch into a 3D model with view and structural awareness, which
addresses the challenge of sparse sketch input and view ambiguity. We conducted
extensive experiments synthetic and real-world datasets and achieved
state-of-the-art (SOTA) results in both sketch view estimation and 3D modeling
performance. According to our user study, our method of performing 3D modeling
in a scene is 5x faster than conventional methods. Users are also more
satisfied with the generated 3D model than the results of existing methods.Comment: IEEE Transactions on MultiMedi
Panoptic NeRF: 3D-to-2D Label Transfer for Panoptic Urban Scene Segmentation
Large-scale training data with high-quality annotations is critical for
training semantic and instance segmentation models. Unfortunately, pixel-wise
annotation is labor-intensive and costly, raising the demand for more efficient
labeling strategies. In this work, we present a novel 3D-to-2D label transfer
method, Panoptic NeRF, which aims for obtaining per-pixel 2D semantic and
instance labels from easy-to-obtain coarse 3D bounding primitives. Our method
utilizes NeRF as a differentiable tool to unify coarse 3D annotations and 2D
semantic cues transferred from existing datasets. We demonstrate that this
combination allows for improved geometry guided by semantic information,
enabling rendering of accurate semantic maps across multiple views.
Furthermore, this fusion process resolves label ambiguity of the coarse 3D
annotations and filters noise in the 2D predictions. By inferring in 3D space
and rendering to 2D labels, our 2D semantic and instance labels are multi-view
consistent by design. Experimental results show that Panoptic NeRF outperforms
existing semantic and instance label transfer methods in terms of accuracy and
multi-view consistency on challenging urban scenes of the KITTI-360 dataset.Comment: Project page: https://fuxiao0719.github.io/projects/panopticnerf
Pre‐symptomatic transmission of novel coronavirus in community settings
We used contact tracing to document how COVID‐19 was transmitted across 5 generations involving 10 cases, starting with an individual who became ill on January 27. We calculated the incubation period of the cases as the interval between infection and development of symptoms. The median incubation period was 6.0 days (interquartile range, 3.5‐9.5 days). The last two generations were infected in public places, 3 and 4 days prior to the onset of illness in their infectors. Both had certain underlying conditions and comorbidity. Further identification of how individuals transmit prior to being symptomatic will have important consequences.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163478/2/irv12773.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163478/1/irv12773_am.pd
An Analysis of Relationship Between RAS Mutations and Prognosis of Primary Tumour Resection for Metastatic Colorectal Cancer Patients
Background/Aims: Non-radical primary tumour resection (PTR) of asymptomatic metastatic colorectal cancer (mCRC) can prolong survival time of some patients. Patients with mutated RAS gene have worse survival outcome. This study aimed to investigate the impact of RAS gene mutations on the prognosis of asymptomatic unresectable mCRC patients who underwent PTR. Methods: A retrospective observational cohort study was deduced among mCRC patients who experienced PTR or had intact primary tumour (IPT). All of them had the primary tumour tissue genotyping tested for RAS (KRAS and NRAS) gene mutations. The tumour-related overall survival (OS) time and progression-free survival (PFS) time was estimated. From January 2011 to June 2014, 421 mCRC patients with asymptomatic, unresectable, metastatic disease were enrolled in this study. Among them, 282 patients underwent PTR and 139 patients had IPT. Results: The mutation rate of RAS was 53.8% (221/411). With a median followed-up time of 46.5 months, the overall survival time of mCRC patients harboring wtRAS or mtRAS was 28.0 versus 22.0 months (p = 0.043) in PTR group and was 21.6 versus 17.8 months (p=0.071) in IPT groups. A Multivariate regression analysis suggested that RAS gene (p=0.039, HR=1.288,95%CI [1.072∼2.911]), metastatic organ number (p=0.033, HR=3.091,95%CI [1.090∼5.755]) and systemic therapy response (p=0.019, HR=0.622,95%CI [0.525∼0.811]) were independent prognostic factors in PTR population. Conclusion: We found that wild-type RAS gene was a favorable factor for the asymptomatic unresectable mCRC patients experiencing PTR
Impact of cytotoxic T lymphocytes immunotherapy on prognosis of colorectal cancer patients
BackgroundExpansion and activation of cytotoxic T lymphocytes (CTLs) in vitro represents a promising immunotherapeutic strategy, and CTLs can be primed by dendritic cells (DCs) loaded with tumor-associated antigens (TAAs) transformed by recombinant adeno-associated virus (rAAV). This study aimed to explore the impact of rAAV-DC-induced CTLs on prognosis of CRC and to explore factors associated with prognosis.MethodsThis prospective observational study included patients operated for CRC at Yan’an Hospital Affiliated to Kunming Medical University between 2016 and 2019. The primary outcome was progression-free survival (PFS), secondary outcomes were overall survival (OS) and adverse events. Totally 49 cases were included, with 29 and 20 administered rAAV-DC-induced CTL and chemotherapy, respectively.ResultsAfter 37-69 months of follow-up (median, 54 months), OS (P=0.0596) and PFS (P=0.0788) were comparable between two groups. Mild fever occurred in 2 (6.9%) patients administered CTL infusion. All the chemotherapy group experienced mild-to-moderate adverse effects, including vasculitis (n=20, 100%), vomiting (n=5, 25%), nausea (n=17, 85%) and fatigue (n=17, 85%).ConclusionsLymphatic metastasis (hazard ratio [HR]=4.498, 95% confidence interval [CI]: 1.290-15.676; P=0.018) and lower HLA-I expression (HR=0.294, 95%CI: 0.089-0.965; P=0.044) were associated with poor OS in the CTL group. CTLs induced by rAAV-DCs might achieve comparable effectiveness in CRC patients compare to chemotherapy, cases with high tumor-associated HLA-I expression and no lymphatic metastasis were more likely to benefit from CTLs
Low spin spectroscopy of neutron-rich 43,44,45Cl via {\beta} and (\beta}n decay
{\beta} decay of neutron-rich isotopes 43,45 S,studied at the National
Superconducting Cyclotron Laboratory is reported here. {\beta} delayed {\gamma}
transitions were detected by an array of 16 clover detectors surrounding the
Beta Counting Station which consists of a 40x40 Double Sided Silicon Strip
Detector followed by a Single Sided Silicon Strip Detector. {\beta} decay
half-lives have been extracted for 43,45 S by correlating implants and decays
in the pixelated implant detector with further coincidence with {\gamma}
transitions in the daughter nucleus. The level structure of 43,45 Cl is
expanded by the addition of 20 new {\gamma} transitions in 43Cl and 8 in 45 Cl
with the observation of core excited negative-parity states for the first time.
For 45 S decay, a large fraction of the {\beta} decay strength goes to delayed
neutron emission populating states in 44 Cl which are also presented.
Comparison of experimental observations is made to detailed shell-model
calculations using the SDPFSDG-MU interaction to highlight the role of the
diminished N = 28 neutron shell gap and the near degeneracy of the proton s 1/2
and d 3/2 orbitals on the structure of the neutron-rich Cl isotopes. The
current work also provides further support to a ground state spin-parity
assignment of 3/2 + in 45 Cl
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