Acellular nerve allografts in corneal neurotisation: an inappropriate choice

2019 ◽  
Vol 104 (2) ◽  
pp. 149-150 ◽  
Author(s):  
Nate Jowett ◽  
Roberto Pineda II
Keyword(s):  
Author(s):  
Christopher D. Wickens ◽  
Linda Onnasch ◽  
Angelina Sebok ◽  
Dietrich Manzey

Objective The aim was to evaluate the relevance of the critique offered by Jamieson and Skraaning (2019) regarding the applicability of the lumberjack effect of human–automation interaction to complex real-world settings. Background The lumberjack effect, based upon a meta-analysis, identifies the consequences of a higher degree of automation—to improve performance and reduce workload—when automation functions as intended, but to degrade performance more, as mediated by a loss of situation awareness (SA) when automation fails. Jamieson and Skraaning provide data from a process control scenario that they assert contradicts the effect. Approach We analyzed key aspects of their simulation, measures, and results which we argue limit the strength of their conclusion that the lumberjack effect is not applicable to complex real-world systems. Results Our analysis revealed limits in their inappropriate choice of automation, the lack of a routine performance measure, support for the lumberjack effect that was actually provided by subjective measures of the operators, an inappropriate assessment of SA, and a possible limitation of statistical power. Conclusion We regard these limitations as reasons to temper the strong conclusions drawn by the authors, of no applicability of the lumberjack effect to complex environments. Their findings should be used as an impetus for conducting further research on human–automation interaction in these domains. Applications The collective findings of both Jamieson and Skraaning and our study are applicable to system designers and users in deciding upon the appropriate level of automation to deploy.


2015 ◽  
Vol 1123 ◽  
pp. 42-45
Author(s):  
Mohammad Tauviqirrahman ◽  
Muchammad ◽  
Rifky Ismail ◽  
J. Jamari ◽  
D.J. Schipper

The use of conventional lubricant such as hexadecane and toluene in micro-bearings has shown poor performance due to their hydrophilicity. High friction between the lubricated surfaces could lead to the occurrence of stiction which limits the functionality of a micro-bearing. In order to assess this strategy, a lubrication model of a micro-slider bearing with modified surface was used to simulate the technology. Friction, hydrophobic zone and hydrophobicity coefficient were evaluated based on the modified Reynolds equation. Results showed that in general the application of a hydrophobic coating has a significant improvement in reducing friction. Further, particular care must be taken in choosing the hydrophobic coating zone; an inappropriate choice of this zone will lead to a deterioration of the friction. This finding may have useful implications to accelerate the development of micro-bearings.


1980 ◽  
Vol 239 (5) ◽  
pp. R424-R427 ◽  
Author(s):  
A. A. Marino ◽  
J. M. Cullen ◽  
M. Reichmanis ◽  
R. O. Becker ◽  
F. X. Hart

The action of a 60-Hz, 5 kV/m electric field on erythrocyte parameters in mice was determined. No effects attributable to the magnitude of the field were found, but a transition either from or to an environment containing the field caused decreased red blood cell concentrations and decreased hematocrits. The failure of others to observe effects on erythrocyte parameters following exposure to low-frequency electric fields may have been due to an inappropriate choice of duration of exposure.


2014 ◽  
Vol 945-949 ◽  
pp. 3287-3290
Author(s):  
Wen Li Tian ◽  
Cheng Xuan Cao

This paper focuses on the high transportation costs problem of the finished vehicle existing in the current vehicle logistics industry, which results from the inappropriate choice of the transport mode. Firstly, we establish a 0-1 programming model to select the integrated transportation mode quantitatively; Secondly, we solve the model by searching method which based on time constraint and capacity constraints; Finally, a case about the selection and optimization of the finished vehicles’ transportation mode in Anji Automotive Logistics Co.,Ltd are introduced to verify the model. The case results indicate that in the premise of meeting the requirement of time, the integrated transportation can greatly reduce the total transportation costs, which have significant implications for future reference in the choice of finished vehicle transportation.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Yi Tan ◽  
Jesper Ødum Nielsen ◽  
Gert Frølund Pedersen

For radio channels with broad bandwidth resource, such as those often used for ultrawideband (UWB) and millimeter wave (mmwave) systems, the Wide-Sense Stationary Uncorrelated Scattering (WSSUS) and spatial stationary assumptions are more critical than typical cellular channels with very limited bandwidth resource. This paper studies spatial stationarity and bandwidth dependency of the Multipath Component (MPC) parameters, and the concept of local region of stationarity (LRS) is used as the measure of the physical stationarity region. LRS calculation results based on channel measurements show that the size of LRS is bandwidth dependent in all measured bands, 2–4 GHz, 14–16 GHz, and 28–30 GHz. The results in this paper point out that an inappropriate choice of bandwidth in channel parameter estimation could violate spatial stationary assumptions. The paper indicates LRS sizes for different bandwidths in the three bands.


2007 ◽  
Vol 35 (1) ◽  
pp. 13-22
Author(s):  
C. Sri Gayatri ◽  
L.M.F. Purwanto

The natural disaster in Nabire in February 2004 and November 2004 has left a noumerous effects on buildings. Many buildings have destroyed because of the terrifying effect of natural disaster which caused a big loss both for material and for the human safety. However, the misapplication of construction and inappropriate choice of material almost cause the terrible damage. After the natural disaster passed, the only left is mostly on the long time needed to build the buildings for people who suffer from the disaster. Because of this problem above, many people usually stay in uncomfortable places such a tend, and this condition creates social and health problems. Concerning the problem above, it is needed to create the "quick built house" which is hopefully can be accepted by the community to cope with the terrifying effect of the natural disaster.In the first year of this research, the data concerning traditional architecture and vernacular architecture in Nabire will be collected. This step will be done in order to understand more detail about all the problem faced and identified all the potential aspects which can be developed to build house for people. The deepest study of vernacular architecture is expected not only to make the house close to the uniqueness of the local activities and culture, but also to make it understandable and built easily by the people/community, because its construction and architecture have become part of their life. Abstract in Bahasa Indonesia : Pada saat bencana alam di Nabire yang terjadi Februari 2004 dan November 2004, banyak bangunan roboh dan rusak. Kerugian sangat besar dan mengakibatkan kerugian baik material maupun keselamatan manusia. Kerusakan yang parah sering diakibatkan oleh salahnya penerapan konstruksi dan salah dalam pemilihan bahan bangunan. Sementara itu pasca bencana, menyisakan kesulitan berupa lamanya membangun bangunan penampungan korban bencana, sehingga seringkali korban bencana hanya ditampung di tenda saja. Akibatnya muncul masalah sosial dan kesehatan. Bangunan yang roboh juga membutuhkan waktu yang lama untuk dibangun kembali. Hal ini mendorong pemikiran untuk mengembangkan rumah cepat bangun yang dapat diterima masyarakat, pada saat bencana telah berlalu. Pada penelitian tahun I ini, dilakukan pengumpulan data tentang arsitektur tradisional dan arsitektur vernakular di Nabire, untuk memahami secara lebih dekat segala permasalahan yang harus dihadapi dan potensi yang dapat dikembangkan untuk membangun rumah Rakyat. Penggalian arsitektur vernakular, diharapkan tidak hanya mendekatkan rumah tinggal yang akan dibangun kembali nantinya, sesuai dengan segala aktifitas dan budaya masyarakat setempat, namun juga untuk lebih mudah dipahami dan mudah dikerjakan sendiri oleh masyarakat, karena bentuk konstruksi dan arsitekturnya sudah menjadi bagian dari kehidupan mereka. Kata kunci: arsitektur tradisonal, vernakular arsitektur, gempa di Nabire.


1996 ◽  
Vol 24 (6) ◽  
pp. 694-698 ◽  
Author(s):  
B. F. Horan ◽  
J. C. Warden

The Special Committee Investigating Deaths Under Anaesthesia in New South Wales classified 1503 deaths which occurred in the years 1984 to 1990 during, within 24 hours of, or as a result of anaesthesia. One hundred and seventy-two (11.4%) of these were attributed definitely, probably or jointly to factors under the anaesthetists’ control. One hundred and forty-four (9.6%) of the 1503 deaths classified occurred in patients undergoing urgent non-emergency operations of which 45 (31.3%) were attributed to anaesthetic factors. A specialist anaesthetist either gave the anaesthetic or was present for part or all of it in 35 of these 45 cases. In 22 the hospital was a metropolitan teaching hospital. General anaesthesia was employed in 31 cases and major regional block (10 spinals and 4 epidurals) in the others. The commonest type of surgery was orthopaedic (26 cases), particularly for fractured neck of femur (20 cases). There were no deaths attributed to anaesthetic factors in cases of this degree of urgency in patients less than 16 years old. The factors under the anaesthetists’ control most often identified as contributing to death were inadequate preparation for anaesthesia and surgery (18 cases, 12 of which were jointly attributed to the surgeon); inappropriate choice or application of technique (17); inadequate postoperative care (12 cases); and overdose (11 cases). If improved outcomes are to be achieved for patients having operations of this degree of urgency, greater attention must be paid to these aspects of their anaesthetic management.


2010 ◽  
Vol 33 ◽  
pp. 631-635
Author(s):  
A.P. Hu ◽  
D.J. Kong ◽  
W. Zhu

The requirements on the movement law of the follower imposed by disc cam mechanism of roller follower are considered, and the influencing factors of the relative motion between the roller and the cam contour are investigated. The requirements on the roller radius for the rolling motion of the roller that is relative to the cam contour are analyzed. It can be found that the constant speed movement, one of the common follower motion laws, cannot be applied alone to roller follower disc cam mechanism; otherwise movement distortion for the follower will happen. The movement distortion caused by inappropriate choice of the movement law can not be avoided by increasing cam base circle radius or by decreasing roller radius. There is a required minimum roller radius for the relative movement between the roller and the cam contour to be rolling movement. The minimum radius is inversely proportional to the rolling friction coefficient between the roller and the cam contour, proportional to the radius of the friction circle of the revolute pair between the roller and the follower lever, and independent of the load of the cam mechanism, pressure angle and other dimension parameters.


Author(s):  
Samden D. Lhatoo ◽  
Nuria Lacuey ◽  
Philippe Ryvlin

The growing requirement for invasive EEG in presurgical evaluation of intractable focal epilepsy has been driven largely by the increasing complexity of epilepsy surgery cases. Extratemporal surgeries now exceed anterior temporal lobe resections for mesial temporal sclerosis, and the proportion of patients undergoing invasive EEGs has significantly increased. Half of all patients undergoing stereotactic EEG (SEEG) evaluations are MRI-negative (usually with focal cortical dysplasia type 1 or 2) and a third are reoperations for failed resective or palliative surgery. Certain principles guide the decision to use invasive EEG and the choice of invasive EEG technique. SEEG has distinct advantages, as do subdural grid evaluations and intraoperative corticography. The consequences of loose hypotheses in the decision to invasively evaluate a patient, and of inappropriate choice of technique, include poor seizure outcomes after surgery, morbidity, and mortality. This chapter discusses the guiding principles for invasive studies of the human epileptic brain.


2018 ◽  
Vol 247 ◽  
pp. 00014 ◽  
Author(s):  
Joanna Rakowska

The article provides studies concerning the selection for the usage of firefighting foam in the aspect of human, property, environmental safety and sustainable development. Foam concentrates are products of the chemical industry, which, due to the type of raw materials, technology, usage method and waste disposal involved, are an important element of the industrial and environmental safety. Considering the range of extinguishing concentrates available on the market, with their different scope and performance effectiveness, it is necessary to responsibly plan purchases of required extinguishing agents. For testing all types of firefighting foam agent: synthetic, aqueous film forming, protein, fluoroprotein and fluoroprotein film forming concentrates were used. The standard test method ISO 7203-1:2011 for low-expansion foams used for the control, extinction and inhibition of reignition of fires of water-immiscible liquids was applied. The use of an appropriately selected and properly concentrated firefighting foam to extinguish a fire allows decreasing the duration of the fire and its consequences for the environment. The amount of used extinguishing agents will be substantially smaller. In the article the impact of considered use of firefighting foams on their effectiveness and potential dangers resulting from an inappropriate choice was shown.


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