The effects of physical damage on TEWL

2002 ◽  
pp. 275-285
Author(s):  
R Chilcott ◽  
A Patel ◽  
Z Ashley ◽  
J Hughes ◽  
J Parkes
Keyword(s):  
Author(s):  
R.J. Mount ◽  
R.V. Harrison

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.


Author(s):  
K. N. Hooghan ◽  
K. S. Wills ◽  
P.A. Rodriguez ◽  
S.J. O’Connell

Abstract Device repair using Focused Ion Beam(FIB) systems has been in use for most of the last decade. Most of this has been done by people who have been essentially self-taught. The result has been a long learning curve to become proficient in device repair. Since a great deal of the problem is that documentation on this “art form” is found in papers from many different disciplines, this work attempts to summarize all of the available information under one title. The primary focus of FIB device repair is to ensure and maintain device integrity and subsequently retain market share while optimizing the use of the instrument, usually referred to as ‘beam time’. We describe and discuss several methods of optimizing beam time. First, beam time should be minimized while doing on chip navigation to reach the target areas. Several different approaches are discussed: dead reckoning, 3-point alignment, CAD-based navigation, and optical overlay. Second, after the repair areas are located and identified, the desired metal levels must be reached using a combination of beam currents and gas chemistries, and then filled up and strapped to make final connections. Third, cuts and cleanups must be performed as required for the final repair. We will discuss typical values of the beam currents required to maintain device integrity while concurrently optimizing repair time. Maintaining device integrity is difficult because of two potentially serious interactions of the FIB on the substrate: 1) since the beam consists of heavy metal ions (typically Gallium) the act of imaging the surface produces some physical damage; 2) the beam is positively charged and puts some charge into the substrate, making it necessary to use great care working in and around capacitors or active areas such as transistors, in order to avoid changing the threshold voltage of the devices. Strategies for minimizing potential damage and maximizing quality and throughput will be discussed.


Author(s):  
Wayan Budiarsa Suyasa ◽  
Sri Kunti Pancadewi G. A ◽  
Iryanti E. Suprihatin ◽  
Dwi Adi Suastuti G. A.

In order to maintain the environmental carrying capacity of coastal tourism, this research was conducted to determine the condition of river water environmental pollution in the Petitenget beach area and pollutant source activities. Determination of water quality is carried out by analyzing the water quality taken at several sampling points in the four rivers that lead to the Petitenget beach. Determined the pollution index value (IP) of the physical chemical and biological pollution parameters. The results showed that the four rivers that flow into the Petitenget Beach area had been contaminated with indications of pH, BOD, COD, ammonia, Coliform and E. coli which exceeded water quality category III class quality (PerGub Bali No 16 Year 2016). The four rivers are included in the criteria of severe contamination. The four rivers have experienced physical damage or structural changes that have very high discharge fluctuations both in quantity and quality. Slimy basic structure, smelly and slum aesthetic waters. While the indication of the impact of pollution is waste water which is directly discharged into the river from hotels, restaurants, homestays, commercial centers and settlements.


Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Yuan Su ◽  
Yang Xu ◽  
Tao Cui ◽  
Xiaojun Gao ◽  
Guoyi Xia ◽  
...  

Abstract Background How to control the physical damage during maize kernel harvesting is a major problem for both mechanical designers and plant breeders. A limitation of addressing this problem is lacking a reliable method for assessing the relation between kernel damage susceptibility and threshing quality. The design, construction, and testing of a portable tool called “HANDY”, which can assess the resistance to mechanical crushing in maize kernel. HANDY can impact the kernel with a special accelerator at a given rotating speed and then cause measurable damage to the kernel. These factors are varied to determine the ideal parameters for operating the HANDY. Results Breakage index (BI, target index of HANDY), decreased as the moisture content of kernel increased or the rotating speed decreased within the tested range. Furthermore, the HANDY exhibited a greater sensitivity in testing kernels at higher moisture level influence on the susceptibility of damage kernel than that in Breakage Susceptibility tests, particularly when the centrifugation speed is about 1800 r/min and the centrifugal disc type is curved. Considering that the mechanical properties of kernels vary greatly as the moisture content changes, a subsection linear (average goodness of fit is 0.9) to predict the threshing quality is built by piecewise function analysis, which is divided by kernel moisture. Specifically, threshing quality is regarded as a function of the measured result of the HANDY. Five maize cultivars are identified with higher damage resistance among 21 tested candidate varieties. Conclusions The HANDY provides a quantitative assessment of the mechanical crushing resistance of maize kernel. The BI is demonstrated to be a more robust index than breakage susceptibility (BS) when evaluating threshing quality in harvesting in terms of both reliability and accuracy. This study also offers a new perspective for evaluating the mechanical crushing resistance of grains and provides technical support for breeding and screening maize varieties that are suitable for mechanical harvesting.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Faheem Aslam ◽  
Hyoung-Goo Kang ◽  
Khurrum Shahzad Mughal ◽  
Tahir Mumtaz Awan ◽  
Yasir Tariq Mohmand

AbstractTerrorism in Pakistan poses a significant risk towards the lives of people by violent destruction and physical damage. In addition to human loss, such catastrophic activities also affect the financial markets. The purpose of this study is to examine the impact of terrorism on the volatility of the Pakistan stock market. The financial impact of 339 terrorist attacks for a period of 18 years (2000–2018) is estimated w.r.t. target type, days of the week, and surprise factor. Three important macroeconomic variables namely exchange rate, gold, and oil were also considered. The findings of the EGARCH (1, 1) model revealed that the terrorist attacks targeting the security forces and commercial facilities significantly increased the stock market volatility. The significant impact of terrorist attacks on Monday, Tuesday, and Thursday confirms the overreaction of investors to terrorist news. Furthermore, the results confirmed the negative linkage between the surprise factor and stock market returns. The findings of this study have significant implications for investors and policymakers.


2021 ◽  
Vol 11 (12) ◽  
pp. 5453
Author(s):  
Hwa-Seob Song ◽  
Jae-Hong Woo ◽  
Jong-Yun Won ◽  
Byung-Ju Yi

Conventional vascular intervention (VI) procedures are typically performed manually under exposure to X-rays, whereby several problems are presented that need to be addressed owing to the patients and doctors being exposed to large amounts of radiation. In such cases, employing radiation protection units is not a long-term solution to avoid physical damage. Therefore, to overcome these issues, we propose a robotic VI system in this study. Moreover, we compare the extent of radiation exposure in the case of the conventional manual VI procedure with that in the case of the robotic procedure. The radiation exposure is then analyzed from the perspective of the doctor. Subsequently, the results of usability tests for two proposed master devices are presented in terms of the NASA task load index (NASA-TLX) and the system usability scale (SUS) score. To verify the effectiveness of the robotic VI system, animal experiments are conducted using a pig model. Among the two types of master devices tested with the proposed robotic VI system, the ergonomically designed 2-degree-of-freedom master device is found to be more effective than the joystick-type device in terms of the usability test scores. Hence, the proposed robotic VI procedure is shown to be advantageous in terms of reducing radiation exposure and improving usability.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ki Hyun Nam ◽  
Jihan Kim ◽  
Yunje Cho

AbstractThe serial crystallography (SX) technique enables the determination of the room-temperature structure of a macromolecule while causing minimal radiation damage, as well as the visualization of the molecular dynamics by time-resolved studies. The fixed-target (FT) scanning approach is one method for SX sample delivery that minimizes sample consumption and minimizes physical damage to crystals during data collection. Settling of the crystals on the sample holder in random orientation is important for complete three dimensional data collection. To increase the random orientation of crystals on the sample holder, we developed a polyimide mesh-based sample holder with irregular crystal mounting holes for FT-SX. The polyimide mesh was fabricated using a picosecond laser. Each hole in the polyimide mesh has irregularly shaped holes because of laser thermal damage, which may cause more crystals to settle at random orientations compared to regular shaped sample holders. A crystal sample was spread onto a polyimide-mesh, and a polyimide film was added to both sides to prevent dehydration. Using this sample holder, FT-SX was performed at synchrotron and determined the room-temperature lysozyme structure at 1.65 Å. The polyimide mesh with irregularly shaped holes will allow for expanded applications in sample delivery for FT-SX experiments.


Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2942
Author(s):  
Tamara Mc Erlain ◽  
Aileen Burke ◽  
Cristina M. Branco

To prevent cancer cells replacing and outnumbering their functional somatic counterparts, the most effective solution is their removal. Classical treatments rely on surgical excision, chemical or physical damage to the cancer cells by conventional interventions such as chemo- and radiotherapy, to eliminate or reduce tumour burden. Cancer treatment has in the last two decades seen the advent of increasingly sophisticated therapeutic regimens aimed at selectively targeting cancer cells whilst sparing the remaining cells from severe loss of viability or function. These include small molecule inhibitors, monoclonal antibodies and a myriad of compounds that affect metabolism, angiogenesis or immunotherapy. Our increased knowledge of specific cancer types, stratified diagnoses, genetic and molecular profiling, and more refined treatment practices have improved overall survival in a significant number of patients. Increased survival, however, has also increased the incidence of associated challenges of chemotherapy-induced morbidity, with some pathologies developing several years after termination of treatment. Long-term care of cancer survivors must therefore become a focus in itself, such that along with prolonging life expectancy, treatments allow for improved quality of life.


2021 ◽  
Vol 22 (13) ◽  
pp. 7043
Author(s):  
Shaida Ouladan ◽  
Alex Gregorieff

Despite the environmental constraints imposed upon the intestinal epithelium, this tissue must perform essential functions such as nutrient absorption and hormonal regulation, while also acting as a critical barrier to the outside world. These functions depend on a variety of specialized cell types that are constantly renewed by a rapidly proliferating population of intestinal stem cells (ISCs) residing at the base of the crypts of Lieberkühn. The niche components and signals regulating crypt morphogenesis and maintenance of homeostatic ISCs have been intensely studied over the last decades. Increasingly, however, researchers are turning their attention to unraveling the mechanisms driving gut epithelial regeneration due to physical damage or infection. It is now well established that injury to the gut barrier triggers major cell fate changes, demonstrating the highly plastic nature of the gut epithelium. In particular, lineage tracing and transcriptional profiling experiments have uncovered several injury-induced stem-cell populations and molecular markers of the regenerative state. Despite the progress achieved in recent years, several questions remain unresolved, particularly regarding the mechanisms driving dedifferentiation of the gut epithelium. In this review, we summarize the latest studies, primarily from murine models, that define the regenerative processes governing the gut epithelium and discuss areas that will require more in-depth investigation.


Author(s):  
Da-Hye Yeon ◽  
Ji-Bum Chung ◽  
Dong-Hyeon Im

The purpose of this study is to examine the factors of disaster experience that impact the effectiveness of disaster education on school students (children and teens). Following the magnitude 5.4 Pohang earthquake in 2017, Pohang City Hall conducted a school earthquake disaster education program over a period of four months (August to November) in 2018. Professors and graduate students from the Ulsan National Institute of Science and Technology taught around 5000 middle and high school students, while also conducting surveys. The experiences of the Pohang earthquake were analyzed and divided into cognitive responses and emotional responses. Students who felt activated emotional responses, surprise and fear, but not joy, tended to have more effective educational experiences. On the other hand, unpleasant emotional reactions, such as anger and sadness, had a negative effect on educational effectiveness. The cognitive response, which is perceived intensity in this research, did not impact educational effectiveness significantly. These results imply that the emotional responses of students are more important than their cognitive responses in providing a disaster education program. This means that even though an earthquake may be small in magnitude and may not cause physical damage, we still need to provide immediate disaster education to the children and teens if they are surprised and afraid of future disasters.


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