73 research outputs found
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Automated people counting by using low-resolution infrared and visual cameras
Non-contact counting of people in a specified area has many applications for safety, security and commercial purposes. Visible sensors have inherent limitations for this task, being sensitive to variations in ambient lighting and colours in the scene. Infrared imaging can overcome many of these problems, but normally hardware costs are prohibitively expensive. A system for counting people in a scene using a combination of low cost, low-resolution visual and infrared cameras is presented in this paper. The aim of this research was to assess the potential accuracy and robustness of systems using low-resolution images. This approach results in considerable savings on hardware costs, enabling the development of systems which may be implemented in a wide range of applications. The results of 18 experiments show that the system can be accurate to within 3% over a wide range of lighting conditions
Factors associated with low birthweight in term pregnancies: A matched case-control study from rural Pakistan
Low birthweight (LBW) remains a significant public health problem in Pakistan and further understanding of factors associated with LBW is required. We conducted a hospital-based matched case control study to identify risk factors associated with LBW in a rural district of Pakistan. We found that illiteracy (AOR: 2.68; 95% CI: 1.59 - 4.38), nulliparity (AOR: 1.82; 95% CI: 1.26-2.44), having a previous miscarriage/abortion (AOR: 1.22; 95% CI: 1.06-2.35), having \u3c 2 antenatal care (ANC) visits during last pregnancy (AOR: 2.43; 95% CI: 1.34-2.88), seeking ANC in third trimester (AOR: 3.62; 95% CI : 2.14-5.03), non-use of iron folic acid during last pregnancy (AOR: 2.72; 95% CI: 1.75-3.17), having hypertension during last pregnancy (AOR: 1.42; 95% CI: 1.13-2.20), being anemic (AOR: 2.67; 95% CI: 1.65-5.24) and having postpartum weight o
DeepHuMS: Deep Human Motion Signature for 3D Skeletal Sequences
3D Human Motion Indexing and Retrieval is an interesting problem due to the
rise of several data-driven applications aimed at analyzing and/or re-utilizing
3D human skeletal data, such as data-driven animation, analysis of sports
bio-mechanics, human surveillance etc. Spatio-temporal articulations of humans,
noisy/missing data, different speeds of the same motion etc. make it
challenging and several of the existing state of the art methods use hand-craft
features along with optimization based or histogram based comparison in order
to perform retrieval. Further, they demonstrate it only for very small datasets
and few classes. We make a case for using a learned representation that should
recognize the motion as well as enforce a discriminative ranking. To that end,
we propose, a 3D human motion descriptor learned using a deep network. Our
learned embedding is generalizable and applicable to real-world data -
addressing the aforementioned challenges and further enables sub-motion
searching in its embedding space using another network. Our model exploits the
inter-class similarity using trajectory cues, and performs far superior in a
self-supervised setting. State of the art results on all these fronts is shown
on two large scale 3D human motion datasets - NTU RGB+D and HDM05.Comment: Under Review, Conferenc
Neoformation of pedogenic carbonates by irrigation and fertilization and their contribution to carbon sequestration in soil
© 2015 Elsevier B.V. The impact of land use change and farming management on soil organic carbon (SOC) and soil inorganic carbon (SIC), particularly pedogenic carbonates (PC), was assessed in a semi-humid region of China. The SOC and SIC content and stocks were measured, and δ13C values were used to calculate the percentage of PC and lithogenic carbonates (LC) in the total SIC. Over the 39-year period, organic fertilizers at high and low rates (OFH and OFL), mineral fertilizers (MF), and a control site without fertilizers (CK) showed an increase of PC compared to a natural fallow plot (F). The main pathway of SIC accumulation was the neoformation of pedo-atmogenic carbonates contributing to C sequestration of at least 0.38, 0.27, 0.23, and 0.12MgCha-1yr-1 for the OFH, OFL, MF, and CK treatments, respectively. The LC stock remained similar in all treatments except for the CK, where LC was significantly lower than all of the other treatments which suggested dissolution. An increase in OC stocks in response to organic fertilization was not limited to the surface soil, but it continued down the soil profile to a depth of 160cm. The maximum potential for neoformation of PC depends on Ca2+ and Mg2+ availability; in this study these cations were provided by irrigation water. However, organic and mineral fertilizers modify this potential. Without organic and mineral fertilization, the PC formed at the expense of dissolution and re-precipitation of LC, even when substantial quantities of Ca2+ and Mg2+ were present in the soil. Our experimental results indicate that the neoformation of PC should be considered during estimation of soil carbon stocks and sequestration for the development of optimal fertilization, irrigation and land use practices.13
Reinforcing the role of the conventional C-arm - a novel method for simplified distal interlocking
<p>Abstract</p> <p>Background</p> <p>The common practice for insertion of distal locking screws of intramedullary nails is a freehand technique under fluoroscopic control. The process is technically demanding, time-consuming and afflicted to considerable radiation exposure of the patient and the surgical personnel. A new concept is introduced utilizing information from within conventional radiographic images to help accurately guide the surgeon to place the interlocking bolt into the interlocking hole. The newly developed technique was compared to conventional freehand in an operating room (OR) like setting on human cadaveric lower legs in terms of operating time and radiation exposure.</p> <p>Methods</p> <p>The proposed concept (guided freehand), generally based on the freehand gold standard, additionally guides the surgeon by means of visible landmarks projected into the C-arm image. A computer program plans the correct drilling trajectory by processing the lens-shaped hole projections of the interlocking holes from a single image. Holes can be drilled by visually aligning the drill to the planned trajectory. Besides a conventional C-arm, no additional tracking or navigation equipment is required.</p> <p>Ten fresh frozen human below-knee specimens were instrumented with an Expert Tibial Nail (Synthes GmbH, Switzerland). The implants were distally locked by performing the newly proposed technique as well as the conventional freehand technique on each specimen. An orthopedic resident surgeon inserted four distal screws per procedure. Operating time, number of images and radiation time were recorded and statistically compared between interlocking techniques using non-parametric tests.</p> <p>Results</p> <p>A 58% reduction in number of taken images per screw was found for the guided freehand technique (7.4 ± 3.4) (mean ± SD) compared to the freehand technique (17.6 ± 10.3) (<it>p </it>< 0.001). Total radiation time (all 4 screws) was 55% lower for the guided freehand technique compared to conventional freehand (<it>p </it>= 0.001). Operating time per screw (from first shot to screw tightened) was on average 22% reduced by guided freehand (<it>p </it>= 0.018).</p> <p>Conclusions</p> <p>In an experimental setting, the newly developed guided freehand technique for distal interlocking has proven to markedly reduce radiation exposure when compared to the conventional freehand technique. The method utilizes established clinical workflows and does not require cost intensive add-on devices or extensive training. The underlying principle carries potential to assist implant positioning in numerous other applications within orthopedics and trauma from screw insertions to placement of plates, nails or prostheses.</p
Management of colorectal cancer presenting with synchronous liver metastases
Up to a fifth of patients with colorectal cancer (CRC) present with synchronous hepatic metastases. In patients with CRC who present without intestinal obstruction or perforation and in whom comprehensive whole-body imaging confirms the absence of extrahepatic disease, evidence indicates a state of equipoise between several different management pathways, none of which has demonstrated superiority. Neoadjuvant systemic chemotherapy is advocated by current guidelines, but must be integrated with surgical management in order to remove the primary tumour and liver metastatic burden. Surgery for CRC with synchronous liver metastases can take a number of forms: the 'classic' approach, involving initial colorectal resection, interval chemotherapy and liver resection as the final step; simultaneous removal of the liver and bowel tumours with neoadjuvant or adjuvant chemotherapy; or a 'liver-first' approach (before or after systemic chemotherapy) with removal of the colorectal tumour as the final procedure. In patients with rectal primary tumours, the liver-first approach can potentially avoid rectal surgery in patients with a complete response to chemoradiotherapy. We overview the importance of precise nomenclature, the influence of clinical presentation on treatment options, and the need for accurate, up-to-date surgical terminology, staging tests and contemporary management options in CRC and synchronous hepatic metastatic disease, with an emphasis on multidisciplinary care
Cuff inflation time significantly affects blood flow recorded with venous occlusion plethysmography
© 2019, The Author(s). Purpose: We tested whether the values of limb blood flow calculated with strain-gauge venous occlusion plethysmography (VOP) differ when venous occlusion is achieved by automated, or manual inflation, so providing rapid and slower inflation, respectively. Method: In 9 subjects (20–30 years), we calculated forearm blood flows (FBF) values at rest and following isometric handgrip at 70% maximum voluntary contraction (MVC) when rapid, or slower inflation was used. Result: Rapid and slower cuff inflation took 0.23 ± 0.01 (mean ± SEM) and 0.92 ± 0.02 s, respectively, reflecting the range reported in published studies. At rest, FBF calculated from the 1st cardiac cycle after rapid and slower inflation gave similar values: 10.5 ± 1.4 vs. 9.6 ± 1.3 ml dl − 1 min − 1 , respectively (P > 0.05). However, immediately post-contraction, FBF was ~ 40% lower with slower inflation: 54.6 ± 5.1 vs. 33.8 ± 4.2 ml dl − 1 min − 1 (P < 0.01). The latter value was similar to that calculated over the 3rd cardiac cycle following rapid inflation: 2nd cardiac cycle: 40.5 ± 4.5; 3rd cycle: 32.6 ± 4.5 ml dl − 1 min − 1 . Regression analyses of FBFs recorded at intervals post-contraction showed those calculated over the 1st, 2nd, or 3rd cardiac cycles with rapid inflation correlated well with those from the 1st cardiac cycle with manual inflation (r = 0.79, 0.82, 0.79; P < 0.01). However, only the slope for the 3rd cycle with rapid inflation vs. slower inflation was close to unity (2.07, 1.34, and 0.94, respectively). Conclusion: These findings confirm that the 1st cardiac cycle following venous occlusion should be used when calculating FBF using VOP and, but importantly, indicate that cuff inflation should be almost instantaneous; just ≥ 0.9 s leads to substantial underestimation, especially at high flows
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