scholarly journals The moment of tooth: rate, fate and pattern of Pacific lingcod dentition revealed by pulse-chase

2021 ◽  
Vol 288 (1960) ◽  
Author(s):  
E. M. Carr ◽  
A. P. Summers ◽  
K. E. Cohen
Keyword(s):  
Tooth Replacement ◽  
Mineralized Tissue ◽  
Replacement Rate ◽  
Ophiodon Elongatus ◽  
Bony Fishes ◽  
Position Data ◽  
The Moment ◽  
Pharyngeal Jaw ◽  
Functional Position

Tooth replacement rates of polyphyodont cartilaginous and bony fishes are hard to determine because of a lack of obvious patterning and maintaining specimens long enough to observe replacement. Pulse-chase is a fluorescent technique that differentially colours developing mineralized tissue. We present in situ tooth replacement rate and position data for the oral and pharyngeal detentions of Ophiodon elongatus (Pacific lingcod). We assessed over 10 000 teeth, in 20 fish, and found a daily replacement rate of about two teeth (3.6% of the dentition). The average tooth is in the dental battery for 27 days. The replacement was higher in the lower pharyngeal jaw (LPJ). We found no difference between replacement rates of feeding and non-feeding fish, suggesting feeding was not a driver of tooth replacement. Lingcod teeth have both a size and location fate; smaller teeth at one spot will not grow into larger teeth, even if a large tooth nearby is lost. We also found increased rates of replacement at the posterior of the LPJ relative to the anterior. We propose that lingcod teeth do not migrate in the jaw as they develop; their teeth are fated in size and location, erupting in their functional position.

scholarly journals Chromatin fibers observed in situ in frozen hydrated sections. Native fiber diameter is not correlated with nucleosome repeat length.

1994 ◽  
Vol 125 (1) ◽  
pp. 11-19 ◽  
Author(s):  
C L Woodcock
Keyword(s):  
Cell Types ◽  
Repeat Length ◽  
Strong Positive Correlation ◽  
Whole Cells ◽  
Chromosome Architecture ◽  
Chromatin Fibers ◽  
The Moment ◽  
Chicken Erythrocytes ◽  
Patiria Miniata

Chromatin fibers have been observed and measured in frozen hydrated sections of three types of cell (chicken erythrocytes and sperm of Patiria miniata and Thyone briareus) representing an approximately 20-bp range of nucleosomal repeat lengths. For sperm of the starfish P. miniata, it was possible to obtain images of chromatin fibers from cells that were swimming in seawater up to the moment of cryo-immobilization, thus providing a record of the native morphology of the chromatin of these cells. Glutaraldehyde fixation produced no significant changes in the ultrastructure or diameter of chromatin fibers, and fiber diameters observed in cryosections were similar to those recorded after low temperature embedding in Lowicryl K11M. Chromatin fiber diameters measured from cryosections of the three types of nuclei were similar, a striking contrast to the situation for chromatin isolated from these cell types, where a strong positive correlation between diameter and nucleosomal repeat length has been established. The demonstration of chromatin fibers in unfixed whole cells establishes an unequivocal baseline for the study of native chromatin and chromosome architecture. The significant differences between chromatin fibers in nucleo and after isolation supports a previous observation (P. J. Giannasca, R. A. Horowitz, and C. L. Woodcock. 1993. J. Cell Sci. 105:551-561), and suggests that structural studies on isolated material should be interpreted with caution until the changes that accompany chromatin isolation are understood.

scholarly journals Monitoring compliance with sulfur content regulations of shipping fuel by in situ measurements of ship emissions

2015 ◽  
Vol 15 (17) ◽  
pp. 10087-10092 ◽  
Author(s):  
L. Kattner ◽  
B. Mathieu-Üffing ◽  
J. P. Burrows ◽  
A. Richter ◽  
S. Schmolke ◽  
...  
Keyword(s):  
Sulfur Content ◽  
Air Pollutant ◽  
Monitoring Site ◽  
Data Set ◽  
The North ◽  
Position Data ◽  
Gas Measurements ◽  
Set Up ◽  
Carbon Dioxide Co2

Abstract. In 1997 the International Maritime Organisation (IMO) adopted MARPOL Annex VI to prevent air pollution by shipping emissions. It regulates, among other issues, the sulfur content in shipping fuels, which is transformed into the air pollutant sulfur dioxide (SO2) during combustion. Within designated Sulfur Emission Control Areas (SECA), the sulfur content was limited to 1 %, and on 1 January 2015, this limit was further reduced to 0.1 %. Here we present the set-up and measurement results of a permanent ship emission monitoring site near Hamburg harbour in the North Sea SECA. Trace gas measurements are conducted with in situ instruments and a data set from September 2014 to January 2015 is presented. By combining measurements of carbon dioxide (CO2) and SO2 with ship position data, it is possible to deduce the sulfur fuel content of individual ships passing the measurement station, thus facilitating the monitoring of compliance of ships with the IMO regulations. While compliance is almost 100 % for the 2014 data, it decreases only very little in 2015 to 95.4 % despite the much stricter limit. We analysed more than 1400 ship plumes in total and for months with favourable conditions, up to 40 % of all ships entering and leaving Hamburg harbour could be checked for their sulfur fuel content.

In Situ Raman Scattering Studies of the Electrochemical Intercalation of Graphite in Sulfuric Acid

1982 ◽  
Vol 20 ◽  
Author(s):  
C.H. Olk ◽  
V. Yeh ◽  
F.J. Holler ◽  
P.C. Eklund
Keyword(s):  
Sulfuric Acid ◽  
Raman Scattering ◽  
Electrochemical Synthesis ◽  
High Frequency ◽  
In Situ Raman ◽  
Lower Stage ◽  
Electrochemical Intercalation ◽  
The Moment ◽  
Sudden Transition

ABSTRACTIn situ Raman scattering studies of the high-frequency carbon intralayer modes in graphite-H2SO4 have been carried out during the electrochemical intercalation of graphite in sulfuric acid. The data show that within an optical depth of ∼ 200 Å the entire c-face undergoes a sudden transition to the next lower stage (n−1) at the moment when the bulk has just completed forming stage n. Raman data collected in the “overcharge” and “overoxidation” regimes of the electrochemical synthesis indicate rapid shifting of the peaks during these times, indicating a significant increase in the oxidation of the carbon layers.

scholarly journals Method for Detecting the Expression of Bone Matrix Protein by in situ Hybridization Using Decalcified Mineralized Tissue.

1993 ◽  
Vol 26 (4) ◽  
pp. 303-309 ◽  
Author(s):  
SHINTARO NOMURA ◽  
KIMIAKI HIRAKAWA ◽  
JUNSUKE NAGOSHI ◽  
SEIICHI HIROTA ◽  
HYUNG-MIN KIM ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Matrix Protein ◽  
Bone Matrix ◽  
Mineralized Tissue ◽  
Bone Matrix Protein

scholarly journals Implementation of Non-Destructive Evaluation and Process Monitoring in DLP-based Additive Manufacturing

2017 ◽  
Vol 7 (1) ◽  
pp. 100-105 ◽  
Author(s):  
Iaroslav Kovalenko ◽  
Sylvain Verron ◽  
Maryna Garan ◽  
Jiří Šafka ◽  
Michal Moučka
Keyword(s):  
Control System ◽  
Process Monitoring ◽  
Continuous Measurement ◽  
Adhesion Force ◽  
3D Printer ◽  
Digital Light Processing ◽  
Non Destructive Evaluation ◽  
The Moment ◽  
Non Destructive

AbstractThis article describes a method of in-situ process monitoring in the digital light processing (DLP) 3D printer. It is based on the continuous measurement of the adhesion force between printing surface and bottom of a liquid resin bath. This method is suitable only for the bottom-up DPL printers. Control system compares the force at the moment of unsticking of printed layer from the bottom of the tank, when it has the largest value in printing cycle, with theoretical value. Implementation of suggested algorithm can make detection of faults during the printing process possible.

Independent a priori information for reduced intercomparison errors between TROPOMI and TCCON retrievals of methane and carbon monoxide

2020 ◽  
Author(s):  
Johannes Lutzmann ◽  
Ralf Sussmann ◽  
Huilin Chen ◽  
Frank Hase ◽  
Rigel Kivi ◽  
...  
Keyword(s):  
A Priori ◽  
Polar Vortex ◽  
Total Carbon ◽  
Space Agency ◽  
Ongoing Work ◽  
The Status ◽  
Priori Information ◽  
The Moment ◽  
Stratospheric Intrusions

<p>Ground-based column measurements of trace gases by FTIR spectrometers within the Total Carbon Column Observing Network (TCCON) provide accurate ground reference for the validation of the nadir-viewing hyperspectral Tropospheric Monitoring Instrument (TROPOMI) on-board the ESA satellite Sentinel 5 Precursor (S-5P). In such intercomparisons of two independent remote soundings, errors can occur as the a priori profiles used in the respective retrievals are i) differing from each other, and ii) both different from the true atmospheric state at the moment of observation. In certain conditions of atmospheric dynamics, e.g. polar vortex subsidence or stratospheric intrusions, which strongly alter the shape of vertical concentration profiles, these intercomparison errors can become considerable (Ostler et al., 2014).</p><p>In our work funded by the German Space Agency DLR and performed as part of the ESA AO project TCCON4S5P, we search for potential sources of realistic common a priori profiles for S-5P and TCCON CH<sub>4</sub> and CO measurements which reduce these large errors. We examine the performance of a number of chemical transport models and data assimilation systems in reproducing dynamical effects and in minimizing intercomparison errors. In-situ profiles measured by AirCores are used as validation where they are available. We present the status and results of our ongoing work.</p><p>Reference:</p><p>Ostler, A., Sussmann, R., Rettinger, M., Deutscher, N. M., Dohe, S., Hase, F., Jones, N., Palm, M., and Sinnhuber, B.-M.: Multistation intercomparison of column-averaged methane from NDACC and TCCON: impact of dynamical variability, Atmos. Meas. Tech., 7, 4081–4101, doi:10.5194/amt-7-4081-2014, 2014. Ostler, A., Sussmann, R., Rettinger, M., Deutscher, N. M., Dohe, S., Hase, F., Jones, N., Palm, M., and Sinnhuber, B.-M.: Multistation intercomparison of column-averaged methane from NDACC and TCCON: impact of dynamical variability, Atmos. Meas. Tech., 7, 4081–4101, doi:10.5194/amt-7-4081-2014, 2014.</p>

scholarly journals Experience Sampling as a Method for Studying In Situ Organizational Communication

2017 ◽  
Vol 3 (1) ◽  
pp. 63
Author(s):  
Ben Lauren
Keyword(s):  
Experience Sampling ◽  
Lessons Learned ◽  
Project Work ◽  
Original Research ◽  
Constant State ◽  
Communication Practices ◽  
The Moment ◽  
Employee Experience ◽  
Insight Into

The communication flows in organizations seem to be in constant state of flux, and this is particularly true when thinking about how the various strategies and mediated practices people use to interact with peers. As organizations work to establish healthy communication workflows, they need insight into how communication around projects exists in situ (i.e., as it happens in the moment) to better understand and support the employee experience so work can get done. The employee experience with communication across different events, settings, and ideologies plays an important role in meeting the intended outcomes of project work, and learning about the in situ communication practices of teams and individual employees remains an important consideration for organizational researchers. This article describes a method for studying in situ communication in the workplace called experience sampling. The goal for this article is to explain how experience sampling can be used to study communicative events in the workplace by drawing from two datasets of original research. From the use of experience sampling depicted in these case studies, the article indicates lessons learned about using experience sampling to study worker’s in situ communication in the workplace.

scholarly journals Use of the Viscofrit to determine the moment of discarding the thermoxidized beef tallow

2018 ◽  
Vol 69 (4) ◽  
pp. 280
Author(s):  
N. Segura ◽  
L. De Oliveira ◽  
A. Y. Pinchak ◽  
M. A. Grompone
Keyword(s):  
Beef Tallow ◽  
Food Processing ◽  
Low Cost ◽  
Polar Compounds ◽  
High Melting Point ◽  
Measurement Temperature ◽  
Large Dispersion ◽  
The Moment ◽  
Emptying Time

Due to the difficulty in determining polar compounds (PC) using the IUPAC method 2.507, simple and low cost devices for in situ determinations, such as Viscofrit, are commercialized for fried food processing establishments. This device is calibrated for oils but not for fats, such as beef tallow, since materials with a high melting point are rarely used worldwide. A large dispersion was observed in the measurements made with Viscofrit at 48 °C on thermoxidized beef tallow. The maximum emptying time was reached at about 6 hours of thermoxidation, at which point the fat still does not reach the maximum PC level allowed. In this test, a great dispersion in the data and a high percentage of “false values” were observed, which may be due to the presence of fatty solids at the measurement temperature, which affect the emptying time. In order to use Viscofrit for fats, such as beef tallow, it is suggested to perform a calibration at a temperature outside the range established by the manufacturer which ensures the absence of fatty solids, in this case 60 °C. Under these conditions, a maximum emptying time of 37 seconds was obtained.

scholarly journals In situ identification strategy of thermoacoustic stability in annular combustors

2018 ◽  
Vol 10 (4) ◽  
pp. 351-361 ◽  
Author(s):  
Driek Rouwenhorst ◽  
Jakob Hermann ◽  
Wolfgang Polifke
Keyword(s):  
Cylindrical Symmetry ◽  
Mode Shapes ◽  
Stable Operation ◽  
Combustion System ◽  
Azimuthal Mode ◽  
Annular Combustor ◽  
The Moment ◽  
Output Only ◽  
The Individual

In annular combustion systems, thermoacoustic eigenmodes can manifest as standing waves, traveling waves or some form in between. Which dynamic solution appears in a combustor depends on details, regarding the flow field and (unintentional) breaking of the cylindrical symmetry of the annular combustion system. When these details are unknown, the specific behavior cannot be predicted from the characteristics of a single burner. Due to the (nearly) degenerate nature of the acoustic solution, annular eigenmodes come in pairs with practically the same eigenfrequency. In order to identify the thermoacoustic modes, conventional analysis of a spectral peak from a measurement does not suffice, because the peak is a superposition of the two eigenmodes. A method has been proposed to identify the two eigenmodes of given azimuthal mode order from multiple simultaneous measurements around the circumference of the combustion system. Using output-only identification on the acoustic signals, it is possible to estimate the individual mode shapes, frequencies and growth rates of the co-existing eigenmode pair. In this work, the strategy is applied to experimental data from an annular combustor. A split in the growth rate pair is observed during stable operation, depending on the equivalence ratio and flame-to-flame distance. It shows that in situ identification of annular thermoacoustics can reveal subtle dynamic effects, which is useful for testing and online monitoring of annular combustors. The moment when instability occurs can be foreseen under prevailing conditions, with simultaneous identification of the azimuthal mode structure.

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