Experimental disintegration of regular echinoids: roles of temperature, oxygen, and decay thresholds

Paleobiology ◽  
1990 ◽  
Vol 16 (3) ◽  
pp. 247-271 ◽  
Author(s):  
Susan M. Kidwell ◽  
Tomasz Baumiller
Keyword(s):  
Room Temperature ◽  
Upper Cretaceous ◽  
Test Construction ◽  
Primary Role ◽  
Threshold Time ◽  
Order Of Magnitude ◽  
Effects Of Temperature ◽  
Decay Threshold

Laboratory experiments on regular echinoids indicate that low water temperatures retard organic decomposition far more effectively than anoxia, and that the primary role of anoxia in the preservation of articulated multi-element calcareous skeletons may be in excluding scavenging organisms. When tumbled at 20 rpm, specimens that were first allowed to decay for two days in warm seawater (30°C) disintegrated more than six times faster than specimens treated at room temperature (23°C) and more than an order of magnitude faster than specimens treated in cool water (11°C). In contrast, the effects of aerobic versus anerobic decay on disintegration rates were insignificant. The longer the period that specimens were allowed to decay before tumbling, the greater the rate at which specimens disintegrated, until a threshold time that appears to mark the decomposition of collagenous ligaments. This required a few days at 30°C, about two weeks at 23°C, and more than 4 weeks at 11°C for Strongylocentrotus. Up until this threshold, coronas disintegrate by a combination of cross-plate fractures and separation along plate sutures; cross-plate fractures thus can be taphonomic in origin and are not necessarily related to predation. Specimens decayed for longer-than-threshold periods of time disintegrate virtually instantaneously upon tumbling by sutural separation only. Undisturbed coronas can remain intact for months, sufficient time for epibiont occupation. Rates of disintegration were documented semi-quantitatively by recognizing seven stages of test disarticulation, and quantitatively by tensometer measures of test strength and toughness. The effects of temperature and oxygen on decay and the existence of a decay threshold in disintegration should apply at least in a qualitative sense to many other animals whose skeletons consist of multiple, collagen-bound elements.Regular echinoids should still be perceived as taphonomically fragile organisms, but our results suggest the potential for latitudinal as well as bathymetric gradients in the preservation of fossil echinoid faunas. Echinoid preservation under any given set of conditions should also be a function of taxonomic differences in test construction (particularly stereom interlocking along plate sutures) as suggested by previous workers, although our experiments indicate that these effects should only be significant among post-threshold specimens. A survey of regular echinoids from Upper Cretaceous white chalk facies of Britain substantiates the basic experimental patterns, yielding examples of all disarticulation stages and significant taxonomic differences in quality of preservation. A diverse array of borers and encrusters on fossil coronas also corroborates the post-mortem persistence of some tests on mid-latitude seafloors.

scholarly journals Hydroacoustical regularities of food behavior of dolphins

2018 ◽  
Vol 3 (2) ◽  
pp. 81-97
Author(s):  
V. A. Ryabov
Keyword(s):  
Radial Velocity ◽  
Temporal Dynamics ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Acoustic Signals ◽  
Food Behavior ◽  
Individual Fish ◽  
Order Of Magnitude

Hydroacoustic regularities of food behavior of dolphins are determined by characteristics and functionality of their acoustic signals. All the acoustic signals of dolphins are classified depending on their physical characteristics by the theory of signals and echolocation as follows: sequences of ultrashort ultrawideband coherent pulses – ‘clicks’, frequency-modulated (FM) simultones with uniformly distributed tones – ‘whistles’, packets of mutually coherent pulses (CI), packets of mutually noncoherent pulses (NI) and packets of versatile pulses (VI). They play the role of probing signals of six dolphin sonars optimized for solving various echolocation tasks. The possibilities of using the signals by dolphins in searching and classifying food objects by echolocation have been studied in this work on the basis of both experimental data obtained by the researcher and those available in literature. The dolphins can use sequences of ‘clicks’ to detect food objects (individual fish at the distance up to 70–110 m, a school of fish at the distance up to 450–600 m) and conspecifics (dolphins) (at the distance up to 450–600 m) and to classify food objects. The dolphins can use ‘whistles’ to detect food objects (individual fish at the distance up to 2 km, a school of fish at the distance up to 9–13 km) and conspecifics (dolphins) (at the distance up to 9–13 km) and to determine their range and relative radial velocity. ‘Whistles’ provide higher accuracy and the range of echolocation of food objects and conspecifics compared to ‘clicks’ (by more than an order of magnitude). Furthermore, the FM sonar provides the measure of the radial velocity of approaching or distance removing of underwater object to or from a dolphin. However, an acute analysis of the amplitude-time regularities of the fish echo for the purpose of their classification is the advantage of sonar using ‘clicks’. The dolphins can use the packs of CI at the distances shorter than 2.5 m for tracing the position dynamics of the prey aiming at accurate capture. The high hearing resolution of the dolphin in time is about 0.02 ms; it allows processing the subtle temporal dynamics of the echoes. Packs of NI (signals of spoken language) can be used by dolphins to organize various types of association and complex cooperation between themselves when hunting and catching fish. Packets of VI can be used by dolphins to expand the echolocation of the survey area around the dolphin in order to improve the quality of food objects monitoring, regardless of the position of the dolphin’s head, as well as to determine the range, relative radial velocity and class of food objects, at short distances. Evolution and perfection of various types of acoustic signals, sonars and various methods of processing echo signals in dolphins is caused, first of all, by optimization of hydroacoustic regularities of their food behavior, along with the need for orientation in three-dimensional space. One can assume the presence of similar hydroacoustic regularities of food behavior in Odontoceti based on the similarity of their acoustic signals and morphology. The acoustic regularities of food behavior of dolphins and bats are similar, despite the fact that they have different habitats (water and terrestrial-air), and these mammals belong to different orders of the animal kingdom (Сetacea and Chiroptera).

The quality of interaction between mother and child as a factor of formation of health

2016 ◽  
Vol 7 (1) ◽  
pp. 151-155
Author(s):  
Tatiana D Vasilenko ◽  
Marina E Vorobeva
Keyword(s):  
Social Roles ◽  
Social Role ◽  
Psychological Intervention ◽  
Role Playing ◽  
Point Of View ◽  
Primary Role ◽  
Mother And Child ◽  
Early Interaction

The article is devoted research of factors and conditions quality of early interaction between mother and child. In our work it is important that consideration of motherhood from the point of view of social and role-playing component of social identity in connection with the style of readiness to motherhood. These data suggest that in women with adequate style readiness to motherhood to the fore the social role of wife and mother, as well as the role of a professional. Women style with alarming readiness to motherhood hierarchy of social roles are determined by the primary role of the mother. Ignoring the style, readiness to motherhood a woman defines herself as a professional, employee, indicating the rejection of the role of mother with this style. Found communication style, readiness to motherhood in women during pregnancy, quality of early interaction with the child and the health of children in the first 6 months of life. As a result, longitudinal studies of the dynamics of the interaction between mother and infant conclusions, allowing to prevent violations of the contact in the dyad "mother-child" on the stage of pregnancy and after the birth of a child within 6 months. Style the willingness to motherhood influence the formation of social role component of the identity of a woman. During pregnancy formed a stable hierarchy of social roles. It allows you to design individually oriented psychological intervention, but also confronts us with the task to prepare the woman during pregnancy to the adoption of social roles as mothers.

scholarly journals The Role of Dopant Concentration on Conductivity and Mobility of CdTe Thin Films

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Ala J. Al-Douri ◽  
F. Y. Al-Shakily ◽  
Abdalla A. Alnajjar ◽  
Maysoon F. A. Alias
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Thermal Evaporation ◽  
Dopant Concentration ◽  
Glass Substrates ◽  
Order Of Magnitude ◽  
Cdte Thin Films ◽  
P Type ◽  
Substrate Temperatures

Films of CdTe pure and doped with various atomic percentages of Al and Sb (0.5, 1.5 & 2.5) were prepared, and their electrical properties were investigated. The films were prepared by thermal evaporation on glass substrates at two substrate temperatures (Ts=RT& 423 K). The results showed that the conduction phenomena of all the investigated CdTe thin films on glass substrates are caused by two distinct mechanisms. Room temperature DC conductivity increases by a factor of four for undoped CdTe thin films asTsincreases and by 1-2 orders of magnitude with increasing dopant percentage of Al and Sb. In general, films doped with Sb are more efficient than Al-doped films. The activation energy (Ea2) decreases with increasingTsand dopant percentage for both Al and Sb. Undoped CdTe films deposited at RT are p-type convert to n-type with increasingTsand upon doping with Al at more than 0.5%. The carrier concentration decreases asTsincreases while it increases with increasing dopant percentage. Hall mobility decreases more than three times as Al increases whereas it increases about one order of magnitude with increasing Sb percentage in CdTe thin films deposited at 423 K and RT, respectively.

scholarly journals Microbial Spoilage of Plant-Based Meat Analogues

2021 ◽  
Vol 11 (18) ◽  
pp. 8309
Author(s):  
András J. Tóth ◽  
Anna Dunay ◽  
Márton Battay ◽  
Csaba Bálint Illés ◽  
András Bittsánszky ◽  
...  
Keyword(s):  
Food Safety ◽  
Nutrient Content ◽  
Primary Role ◽  
Safety Risk ◽  
Microbial Spoilage ◽  
Microbial Proliferation ◽  
Processing And Storage ◽  
Food Safety Risk

Plant-based meat analogues (i.e., plant-based meat alternatives or substitutes, or vegan meats) are becoming more and more popular. The quality of the available products is constantly increasing therefore their consumption is also increasing. The primary role of meat analogues is to replace the meat component in meals while appropriate nutrient content and hedonic value will be provided as well. The food safety aspects of these newly emerging food products are less investigated. The aim of this study is to compare the microbial spoilage of identical meals prepared with meat and meat analogues to evaluate the food safety risk of meat analogues. In this work, raw protein materials were tested. Moreover, three pairs of meals prepared with or without meat were microbiologically examined during a storage experiment. Microbial contaminants were low in raw protein sources. In the case of hot meals, the microbial proliferation was faster in samples containing meat analogue, especially if the meals were not cooled. The food safety risk of meals prepared with meat analogues is slightly higher than their meat-containing counterparts, therefore more attention needs to be paid to the preparation, processing, and storage of these foods.

Theoretical insight into the disordered structure of (Z)-2-[(E)-(4-methoxybenzylidene)hydrazinylidene]-1,2-diphenylethanone: the role of noncovalent interactions

2018 ◽  
Vol 74 (9) ◽  
pp. 1058-1067
Author(s):  
Xue-Jie Tan ◽  
Di Wang ◽  
Xu-Gang Lei ◽  
Jun-Peng Chen
Keyword(s):  
Room Temperature ◽  
Noncovalent Interactions ◽  
Poor Quality ◽  
X Ray ◽  
Disordered Structure ◽  
Theoretical Insight ◽  
Insight Into ◽  
Shed Light

A global glide disorder has been discovered during an X-ray investigation of the crystal structure of (Z)-2-[(E)-(4-methoxybenzylidene)hydrazinylidene]-1,2-diphenylethanone (MHDE, C22H18N2O2) at room temperature. In another crystal, however, such disorder disappears (still at room temperature). Even though the disorder may be partly due to the poor quality of the harvested crystal, the structure can shed light on the nature of disorder. With the help of quantum chemical calculations, it is found that the global disorder seems to be connected with the need for stabilization of the somewhat rigid but mobile and unstable molecular structure. The most relevant feature driving the packing of the disordered structure concerns the slight perturbations (such as glide) of two or more disorder components (fractional occupancies) distributed throughout the crystal.

scholarly journals Effects of Temperature and Salinity on Coral Bleaching in Laboratory

2022 ◽  
Vol 13 (1) ◽  
pp. 21-25
Author(s):  
Kamonphon Patthanasiri ◽  
◽  
Thaithaworn Lirdwitayaprasit ◽  
Thamasak Yeemin ◽  
Ing-on Thongcamdee ◽  
...  
Keyword(s):  
Water Column ◽  
Coral Bleaching ◽  
Room Temperature ◽  
Synergistic Effects ◽  
Pocillopora Damicornis ◽  
Temperature Level ◽  
Low Salinity ◽  
Zooxanthellae Density ◽  
Effects Of Temperature

Coral bleaching occurs when cell density or the concentration of photosynthetic pigments of the endosymbionts, zooxanthellae are decreased. This incident may possibly be caused by some environmental stresses, especially under conditions of elevated temperature, decrease in water salinity, or a combination of these factors. To determine the role of temperature and salinity on zooxanthellae and coral bleaching this study was conducted in aquariums under laboratory conditions on cauliflower coral Pocillopora damicornis. The samples were collected from three sites around Samaesan Island, Chonburi, Thailand. Three sets of experiments were conducted at three levels of temperature: room temperature 27 (control), 30, and 33 oC respectively. At each temperature level, three levels of salinities; 10, 20 and 30 (control) psu were tested as well. Coral bleaching percentage and zooxanthellae density in the water column were observed every 6 hours during the period of 72 hours. The results showed that when coral exposed to the highest temperature (33 oC) under the lowest salinity (10 psu), 50-90% bleaching was found and higher symbiont densities in the water column were detected. These results suggested that the combination of the high temperature and low salinity had synergistic effects on coral bleaching and zooxanthellae.

The Ethics of Lecturers Based on Islamic Perspective in Al-Washliyah Universities

2017 ◽  
Vol 3 (2) ◽  
pp. 36-43
Author(s):  
Dedi Iskandar Batu Bara
Keyword(s):  
Teaching And Learning ◽  
Descriptive Analysis ◽  
Primary Role ◽  
Campus Environment ◽  
Islamic Perspective ◽  
Character Building ◽  
North Sumatra

This research is conducted by looking at the phenomenon of Moral degradation and student’s ethics in a variety of universities, especially in Indonesia and North Sumatra in particular. The process of teaching and learning in universities level cannot be separated from the role of the lecturers whose primary role is to transform, develop and spread knowledge. Islam regards the lecturers as a scholar with the un-arrogant character, avoiding improper behavior and patient. The Objective of the research: This study is conducted to determine the ethics of lecturers based on Islamic Perspective in Al-Washliyah Universities. This research is significant to be applied in the hope that it can be beneficial towards the student’s character building through the ethics of the lecturers based on the Moslem Syar’i Perspective. The method of research applied is using the descriptive analysis to illustrate and describe the complete description through 4 (four) informants who understand and have a responsibility to the academic’s environment in Universities Al-Washliyah. The achieved result indicates that the ethics of lecturers in the academic’s environment of Al-Washliyah universities towards the process of teaching and learning as well as the activities around the campus environment have been conducting based on the Moslem Syar’i, even though no such a particular binding regulation. This study states that the lecturers cling the Islam Perspective firmly thus there is no such lecturer’s ethics violation findings. To balance the lecturer’s performance in through research, it is necessary to crystallize the ethical model that can be bound and procedural in order to maintain the quality of Al-Washliyah Universities of North Sumatra.

Ultra-Hard Nanostructured Al-Si Thin Films

2005 ◽  
Vol 494 ◽  
pp. 13-18
Author(s):  
Velimir Radmilović ◽  
D. Mitlin ◽  
U. Dahmen
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Mechanical Performance ◽  
High Rate ◽  
Hard Phase ◽  
Two Phase ◽  
Transmission Electron ◽  
Order Of Magnitude ◽  
Dense Distribution

We show that it is possible to use high rate co-evaporation of Al and Si onto room temperature substrates to achieve a novel two-phase nanoscale microstructure. These nanocomposites have a hardness as high as 4GPa (Al-23at.%Si), and display noticeable plasticity. Films with compositions of Al-12at.%Si and pure Al (used as baseline) were analyzed using transmission electron microscopy (TEM). The scale of the Al-12at.%Si microstructure is an order of magnitude finer compared to that of pure Al films. It consists of a dense distribution of spherical nanoscale Si particles separating irregularly-shaped small Al grains. These new structures may have a mechanical performance advantage over conventional single phase nanomaterials due to the role of the dispersed hard phase in promoting strain hardening.

'The Role of the Grain Boundary on the Resistivity of Pb(Fe1/2Nb1/2)O3 at Room Temperature

2002 ◽  
Vol 718 ◽  
Author(s):  
Sang-Bop Lee ◽  
Kwang-Ho Lee ◽  
Hwan Kim
Keyword(s):  
Grain Boundary ◽  
Room Temperature ◽  
Sintered Specimen ◽  
Room Temperature Resistivity ◽  
Boundary Properties ◽  
Order Of Magnitude ◽  
The Difference ◽  
Fe Reduction ◽  
Temperature Resistivity

AbstractThe effect of changing sintering temperature on the grain boundary properties and the room temperature resistivity (ρRT) of Pb(Fe1/2Nb1/2)O3 (PFN) was investigated. Monitering the temperature dependence of resistivity showed that the ρRT's of 1050°C and 1150°C-sintered specimen were 1011ΩEcm and 104ΩEcm respectively, but the resistivity above 300°C became nearly identical. The previous model, that the low resistivity of PFN is due to the electron hopping between Fe2+ and Fe3+ driven by the reduction of PFN, couldn't explain this phenomenon, and the reconsideration of the Fe reduction revealed that the difference of electron concentration between the 1050°C and 1150°C-sintered specimen couldn't exceed one order of magnitude. The role of the grain boundary was introduced in order to account for this phenomenon.

scholarly journals PENGARUH PERENDAMAN EKSTRAK DAUN MANGROVE (Sonneratia caseolaris) TERHADAP PENILAIAN MUTU ORGANOLEPTIK IKAN KUWE (Gnathanodon speciosus) SEGAR

2021 ◽  
Vol 17 (1) ◽  
pp. 25-34
Author(s):  
Nur A Saimima ◽  
Abdul Rahman ◽  
Desri N Manuhutu
Keyword(s):  
Sample Preparation ◽  
Shelf Life ◽  
Leaf Extract ◽  
Room Temperature ◽  
Microbial Growth ◽  
Assessment Data ◽  
Organoleptic Quality ◽  
Sonneratia Caseolaris

Fish is a comestible that is inclined to the deterioration of quality, especially by the activity of rotting microorganisms. One of the efforts to obstruct the decline in fish quality by using natural ingredients, namely mangrove leaves. This study aims to determine the utilization of mangrove leaf extract (Sonneratia caseolaris) on the organoleptic quality of fresh golden trevally fish (Gnathanodon speciosus). The research was conducted in March 2020 at the Marine Hatchery Laboratory and Processing Workshop SUPM in Waiheru Ambon. The research used a laboratory experimental method with several stages, these were sample preparation, mangrove leaf extract preparation, immersion of golden trevally fish in mangrove leaf extract, storage, and analysis of organoleptic assessment data. Organoleptic assessments including eyes, gills, body surface slime, meat (color and appearance), smell and texture were carried out every 6 hours until the quality of the fish was rejected by the panelists. The results showed that soaking mangrove leaf extract can inhibit microbial growth in fish. The concentrations of mangrove leaf extract 2% and 4% could lengthen the shelf life of fresh golden trevally fish at room temperature for 6 hours longer than the control. In addition, the mangrove leaf extract immersion treatment can maintain the organoleptic value of fish. In conclusion, the results of the organoleptic quality assessment of fresh golden trevally fish (Gnathanodon speciosus) in soaking treatment of mangrove leaf extract (Sonneratia caseolaris) with a concentration of 2%-4% can maintain the shelf life of golden trevally fish. This is due to the role of secondary metabolic compounds contained in mangrove leaves which can inhibit microbial growth.   ABSTRAK Ikan merupakan bahan pangan yang sangat mudah mengalami kemunduran mutu terutama oleh aktivitas mikroorganisme pembusuk. Salah satu upaya untuk menghambat penurunan mutu ikan dengan menggunakan bahan alami yaitu daun mangrove. Penelitian ini bertujuan untuk mengetahui pemanfaatan ekstrak daun mangrove (Sonneratia caseolaris) terhadap mutu organoleptik ikan kuwe (Gnathanodon speciosus) segar. Penelitian dilakukan pada bulan Maret 2020 di Laboratorium Hatchery Laut dan Workshop Pengolahan SUPM Waiheru Ambon. Penelitian menggunakan metode experimental laboratories dengan tahapan-tahapan yaitu persiapan sampel, preparasi ekstrak daun mangrove, perendaman ikan kuwe dalam esktrak daun mangrove, penyimpanan, serta analisa data penilaian organoleptik. Penilaian organoleptik meliputi mata, insang, lendir permukaan badan, daging (warna dan kenampakan), bau serta tekstur dilakukan setiap 6 jam sekali sampai mutu ikan ditolak oleh panelis. Hasil penelitian menunjukan bahwa perendaman ekstrak daun mangrove dapat menghambat pertumbuhan mikroba pada ikan. Konsentrasi ekstrak daun mangrove 2% dan 4% dapat memperpanjang daya simpan ikan kuwe segar pada suhu kamar 6 jam lebih lama dibandingkan kontrol. Disamping itu, perlakuan perendaman ekstrak daun mangrove dapat mempertahankan nilai organoleptik ikan. Kesimpulannya Hasil penilaian mutu organoleptik ikan kuwe (Gnathanodon speciosus) segar dalam perlakuan perendaman ekstrak daun mangrove (Sonneratia caseolaris) dengan konsentrasi 2%-4% dapat mempertahankan daya simpan ikan kuwe. Hal ini disebabkan peran senyawa metabolik sekunder yang terkandung pada daun mangrove yang dapat menghambat pertumbuhan mikroba.   Kata Kunci: Sonneratia caseolaris, Gnathanodon speciosus, organoleptik, daun mangrove, ekstrak

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