scholarly journals Improving a Rapid Alignment Method of Tomography Projections by a Parallel Approach

2021 ◽  
Vol 11 (16) ◽  
pp. 7598
Author(s):  
Francesco Guzzi ◽  
George Kourousias ◽  
Alessandra Gianoncelli ◽  
Lorella Pascolo ◽  
Andrea Sorrentino ◽  
...  

The high resolution of synchrotron cryo-nano tomography can be easily undermined by setup instabilities and sample stage deficiencies such as runout or backlash. At the cost of limiting the sample visibility, especially in the case of bio-specimens, high contrast nano-beads are often added to the solution to provide a set of landmarks for a manual alignment. However, the spatial distribution of these reference points within the sample is difficult to control, resulting in many datasets without a sufficient amount of such critical features for tracking. Fast automatic methods based on tomography consistency are thus desirable, especially for biological samples, where regular, high contrast features can be scarce. Current off-the-shelf implementations of such classes of algorithms are slow if used on a real-world high-resolution dataset. In this paper, we present a fast implementation of a consistency-based alignment algorithm especially tailored to a multi-GPU system. Our implementation is released as open-source.

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2505 ◽  
Author(s):  
Ming-Long Wu ◽  
Jong-Chih Chien ◽  
Chieh-Tsai Wu ◽  
Jiann-Der Lee

In many surgery assistance systems, cumbersome equipment or complicated algorithms are often introduced to build the whole system. To build a system without cumbersome equipment or complicated algorithms, and to provide physicians the ability to observe the location of the lesion in the course of surgery, an augmented reality approach using an improved alignment method to image-guided surgery (IGS) is proposed. The system uses RGB-Depth sensor in conjunction with the Point Cloud Library (PCL) to build and establish the patient’s head surface information, and, through the use of the improved alignment algorithm proposed in this study, the preoperative medical imaging information obtained can be placed in the same world-coordinates system as the patient’s head surface information. The traditional alignment method, Iterative Closest Point (ICP), has the disadvantage that an ill-chosen starting position will result only in a locally optimal solution. The proposed improved para-alignment algorithm, named improved-ICP (I-ICP), uses a stochastic perturbation technique to escape from locally optimal solutions and reach the globally optimal solution. After the alignment, the results will be merged and displayed using Microsoft’s HoloLens Head-Mounted Display (HMD), and allows the surgeon to view the patient’s head at the same time as the patient’s medical images. In this study, experiments were performed using spatial reference points with known positions. The experimental results show that the proposed improved alignment algorithm has errors bounded within 3 mm, which is highly accurate.


2021 ◽  
pp. 1-13
Author(s):  
Caroline Jane Taylor ◽  
Joanne Rachel Carr ◽  
David Robert Rounce

Abstract Supraglacial ponds and ice cliffs can dramatically enhance ablation rates on debris-covered glaciers. Supraglacial ponds can also coalesce, forming moraine-dammed lakes at risk of glacial lake outburst flood (GLOF). Given Bhutanese glaciers have some of the highest ice loss rates in the Himalaya and GLOF vulnerability is high, we seek to advance our understanding of the spatial distribution and evolution of supraglacial ponds and ice cliffs. Here, we use high-resolution (3 m) Planet Labs satellite imagery to provide the first short-term, high-resolution dataset of supraglacial pond and ice cliff evolution for three glaciers along the Bhutan–Tibet border from 2016 to 2018. A total of 5754 ponds and 2088 ice cliffs were identified. Large intra-annual changes were observed, with ponded area changes and drainage events coinciding with the seasonality of the Indian Summer Monsoon. On average, ~19% of the total number of ponds had a coincident ice cliff. Pond spatial distribution was driven by ice-surface velocities, with higher numbers of ponds found in areas of low velocity (<8 m a−1). Our study provides the first detailed, quantitative investigation of supraglacial ponds and ice cliffs in Bhutan, providing a framework for further monitoring in this understudied, yet important, region of the Himalaya.


Author(s):  
Gary Bassell ◽  
Robert H. Singer

We have been investigating the spatial distribution of nucleic acids intracellularly using in situ hybridization. The use of non-isotopic nucleotide analogs incorporated into the DNA probe allows the detection of the probe at its site of hybridization within the cell. This approach therefore is compatible with the high resolution available by electron microscopy. Biotinated or digoxigenated probe can be detected by antibodies conjugated to colloidal gold. Because mRNA serves as a template for the probe fragments, the colloidal gold particles are detected as arrays which allow it to be unequivocally distinguished from background.


Author(s):  
Po Fu Chou ◽  
Li Ming Lu

Abstract Dopant profile inspection is one of the focused ion beam (FIB) physical analysis applications. This paper presents a technique for characterizing P-V dopant regions in silicon by using a FIB methodology. This technique builds on published work for backside FIB navigation, in which n-well contrast is observed. The paper demonstrates that the technique can distinguish both n- and p-type dopant regions. The capability for imaging real sample dopant regions on current fabricated devices is also demonstrated. SEM DC and FIB DC are complementary methodologies for the inspection of dopants. The advantage of the SEM DC method is high resolution and the advantage of FIB DC methodology is high contrast, especially evident in a deep N-well region.


2018 ◽  
Author(s):  
Kenneth Belitz ◽  
◽  
Richard B. Moore ◽  
T.L. Arnold ◽  
J.B. Sharpe ◽  
...  

Author(s):  
Marcus Shaker ◽  
Edmond S. Chan ◽  
Jennifer LP. Protudjer ◽  
Lianne Soller ◽  
Elissa M. Abrams ◽  
...  

2013 ◽  
Vol 415 ◽  
pp. 143-148
Author(s):  
Li Hua Zhu ◽  
Xiang Hong Cheng

The design of an improved alignment method of SINS on a swaying base is presented in this paper. FIR filter is taken to decrease the impact caused by the lever arm effect. And the system also encompasses the online estimation of gyroscopes’ drift with Kalman filter in order to do the compensation, and the inertial freezing alignment algorithm which helps to resolve the attitude matrix with respect to its fast and robust property to provide the mathematical platform for the vehicle. Simulation results show that the proposed method is efficient for the initial alignment of the swaying base navigation system.


2021 ◽  
Author(s):  
Mohamed Elkhawaga ◽  
Wael A. Elghaney ◽  
Rajarajan Naidu ◽  
Assef Hussen ◽  
Ramy Rafaat ◽  
...  

Abstract Optimizing the number of casing strings has a direct impact on cost of drilling a well. The objective of the case study presented in this paper is the demonstration of reducing cost through integration of data. This paper shows the impact of high-resolution 3D geomechanical modeling on well cost optimization for the GS327 Oil field. The field is located in the Sothern Gulf of Suez basin and has been developed by 20 wells The conventional casing design in the field included three sections. In this mature field, especially with the challenge of reducing production cost, it is imperative to look for opportunites to optimize cost in drilling new wells to sustain ptoduction. 3D geomechanics is crucial for such cases in order to optimize the cost per barrel at the same time help to drill new wells safely. An old wellbore stability study did not support the decision-maker to merge any hole sections. However, there was not geomechanics-related problems recorded during the drilling the drilling of different mud weights. In this study, a 3D geomechanical model was developed and the new mud weight calculations positively affected the casing design for two new wells. The cost optimization will be useful for any future wells to be drilled in this area. This study documents how a 3D geomechanical model helped in the successful delivery of objectives (guided by an understanding of pore pressure and rock properties) through revision of mud weight window calculations that helped in optimizing the casing design and eliminate the need for an intermediate casing. This study reveals that the new calculated pore pressure in the GS327 field is predominantly hydrostatic with a minor decline in the reservoir pressure. In addition, rock strength of the shale is moderately high and nearly homogeneous, which helped in achieving a new casing design for the last two drilled wells in the field.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e19551-e19551
Author(s):  
Hongbo Yang ◽  
Cynthia Zhengyun Qi ◽  
Anand Dalal ◽  
Vamsi Bollu ◽  
Jie Zhang ◽  
...  

e19551 Background: The AE rates and HRU reported in multiple real-world evidence (RWE) studies of chimeric antigen receptor T-cell (CAR-T) therapies tisa-cel and axi-cel in r/r DLBCL have differed from those in their clinical trials. However, the cost implications from these findings are not well understood in existing literature. This study summarizes information from these RWE studies of tisa-cel and axi-cel and quantifies the associated costs. Methods: A literature review was conducted to identify RWE studies reporting AE rates and HRU of tisa-cel and axi-cel in the United States (US). AE rates and HRU were summarized and the associated costs were estimated using a micro-costing approach. Costs of AE management included hospitalization and pharmacy costs, such as intensive care unit (ICU) stays, inpatient admissions, and medications for the treatment of cytokine release syndrome (CRS) and neurotoxicity events (NE). HRU costs included hospitalization, ICU stays, and outpatient visit costs. Unit costs were from public health databases that are representative of US healthcare system and from literature. Costs were inflated to 2020 US dollars. A range was reported to present evidence if inputs are available from multiple studies. Results were summarized for tisa-cel and axi-cel separately. Results: Four publications were identified: Jaglowski 2019, Pasquini 2019, Riedell 2019, and Jacobson 2020. Across studies, grade 3+ CRS and NE occurred in 1%-4% and 0%-5% of tisa-cel-treated patients and 7%-16% and 20%-35% of axi-cel-treated patients, respectively. Tocilizumab usage was reported in 14%-20% of tisa-cel- and 62%-71% of axi-cel-treated patients. CAR-T infusion was inpatient for 36% of tisa-cel- and 92%-100% of axi-cel-treated patients. The median hospitalization days was 2 for tisa-cel and 15-16 for axi-cel. ICU transfer was observed for 7% and 28%-38% of tisa-cel- and axi-cel-treated patients, respectively, with median stays of 4 and 5 days, respectively. The median number of outpatient visits within 28 days after infusion was 6 for tisa-cel and 4 for axi-cel. The total estimated costs for managing AEs per patient were $843-$1,962 for tisa-cel and $5,979-$10,878 for axi-cel. The total estimated HRU costs per patient were $3,321 for tisa-cel and $32,394-33,166 for axi-cel. Conclusions: RWE studies suggest that patients with r/r DLBCL receiving tisa-cel had numerically lower AE rates, HRU, and cost burden than those receiving axi-cel in the US. The additional cost burden for axi-cel was primarily driven by the incremental ICU and hospitalization care due to a higher proportion of inpatient infusion among patients receiving axi-cel. Further research is warranted to compare the costs associated with the two CAR-Ts in r/r DLBCL.


1974 ◽  
Vol 20 (11) ◽  
pp. 1446-1450 ◽  
Author(s):  
Bernard Century ◽  
William P Vorkink ◽  
Samuel Natelson

Abstract We describe a simple, rapid, and inexpensive unidimensional high-resolution thin-layer chromatographic procedure for screening for aminoacidopathies in newborns. Protein-free filtrates are prepared for ultrafiltration of as little as 10 µl of plasma. A rapid, inexpensive photographic method provides large, high-contrast pictures of the chromatograms for permanent records. A day’s samples can be completed in 3 h, including all phases of the procedure.


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