scholarly journals Escalas do tempo

2021 ◽  
pp. 306-317
Author(s):  
Eric Landowski
Keyword(s):  
Great Effort ◽  
Mesoscopic Scale ◽  
Macroscopic Scale ◽  
Essential Variable ◽  
Physiological Processes ◽  
Long Duration ◽  
Singular Event ◽  
History Of ◽  
Mesoscopic Level ◽  
Different Time Scales

Viral epidemics are processes in which temporality obviously constitutes an essential variable. But different time scales must be distinguished. To see the current pandemic as a singular event is but an illusion due to the “mesoscopic” timescale we are embracing. There is a microscopic scale — that of physiological processes —, a mesoscopic scale, which only allows to see the closest evidence, and a macroscopic scale, that of the ecological determinisms which explain the emergence of the disease in the history of the relationships between species. The article focuses on the mesoscopic level and highlights some semiotic specificities of today’s experience : a temporal suspension, the threat of pure, dramatic and final discontinuity, the behavior of a virus that appears to have “intentionality”, a strong intensity coupled with a long duration, a time of exception, drawn to a final end, and a victory which will only be achieved with great effort.

scholarly journals A Study about the Temporal Constraints on the Martian Yardangs’ Development in Medusae Fossae Formation

2021 ◽  
Vol 13 (7) ◽  
pp. 1316
Author(s):  
Jia Liu ◽  
Zongyu Yue ◽  
Kaichang Di ◽  
Sheng Gou ◽  
Shengli Niu
Keyword(s):  
Size Distribution ◽  
Indirect Method ◽  
Common Method ◽  
Planetary Surface ◽  
Temporal Constraints ◽  
History Of Development ◽  
Long Duration ◽  
History Of ◽  
Dating Method

The age of Mars yardangs is significant in studying their development and the evolution of paleoclimate conditions. For planetary surface or landforms, a common method for dating is based on the frequency and size distribution of all the superposed craters after they are formed. However, there is usually a long duration for the yardangs’ formation, and they will alter the superposed craters, making it impossible to give a reliable dating result with the method. An indirect method by analyzing the ages of the superposed layered ejecta was devised in the research. First, the layered ejecta that are superposed on and not altered by the yardangs are identified and mapped. Then, the ages of the layered ejecta are derived according to the crater frequency and size distribution on them. These ages indicate that the yardangs ceased development by these times, and the ages are valuable for studying the evolution of the yardangs. This indirect dating method was applied to the areas of Martian yardangs in the Medusae Fossae Formation (MFF). The ages of the selected six layered ejecta range from ~0.50 Ga to ~1.5 Ga, indicating that the evolution of the corresponding yardangs had been ceased before these times. Analysis of more layered ejecta craters and superposed yardangs implies that yardangs in the MFF have a long history of development and some yardangs are still in active development.

Perilymph Fistulas

1978 ◽  
Vol 87 (6) ◽  
pp. 797-803 ◽  
Author(s):  
George T. Singleton ◽  
Kathryn Nolan Post ◽  
Marc Simeon Karlan ◽  
Douglas G. Bock
Keyword(s):  
Discriminant Analysis ◽  
Effective Means ◽  
Bed Rest ◽  
Sudden Onset ◽  
Effective Control ◽  
Speech Discrimination ◽  
Mean Values ◽  
Long Duration ◽  
History Of ◽  
Physical Findings

Fifty-one patients suspected of having a perilymph fistula were evaluated. We postulated that many patients with predominantly vestibular complaints had unrecognized perilymph fistulas. An analysis was made of symptoms, physical findings, vestibular and audiometric test results in order to determine appropriate diagnostic criteria for the presence of perilymph fistulas. The patient population was divided into two groups, those with and without fistulas. Data from both groups were compared by mean values of variables, step-wise discriminant analysis, and factor analysis. A history of trauma with sudden onset of dizziness and/or hearing loss should alert the physician to a fistula. Findings of significance were positional nystagmus of short latency and long duration without import of nystagmus direction, canal paresis and reduced speech reception threshold with poor speech discrimination scores. Discriminant analysis correctly classified 19 fistula and 10 nonfistula cases explored operatively and identified two error judgments in 22 nonoperated cases. Bed rest for the first five days proved to be the most effective means of therapy. Surgical intervention with repair of the fistula by perichondrial graft provided effective control of vertigo more frequently than restoration of hearing.

scholarly journals Multiscale Post-Seismic Deformation Based on cGNSS Time Series Following the 2015 Lefkas (W. Greece) Mw6.5 Earthquake

2021 ◽  
Vol 11 (11) ◽  
pp. 4817
Author(s):  
Filippos Vallianatos ◽  
Vassilis Sakkas
Keyword(s):  
Time Series ◽  
Relaxation Time ◽  
Relaxation Times ◽  
Relaxation Mechanism ◽  
Mesoscopic Scale ◽  
Macroscopic Scale ◽  
Epicentral Area ◽  
Arrhenius Dependence ◽  
Seismic Deformation ◽  
Logarithmic Type

In the present work, a multiscale post-seismic relaxation mechanism, based on the existence of a distribution in relaxation time, is presented. Assuming an Arrhenius dependence of the relaxation time with uniform distributed activation energy in a mesoscopic scale, a generic logarithmic-type relaxation in a macroscopic scale results. The model was applied in the case of the strong 2015 Lefkas Mw6.5 (W. Greece) earthquake, where continuous GNSS (cGNSS) time series were recorded in a station located in the near vicinity of the epicentral area. The application of the present approach to the Lefkas event fits the observed displacements implied by a distribution of relaxation times in the range τmin ≈3.5 days to τmax ≈350 days.

Nutritional Assessment of the Handicapped Child

1989 ◽  
Vol 11 (4) ◽  
pp. 109-115
Author(s):  
William H. Dietz ◽  
Linda Bandini
Keyword(s):  
Vitamin D ◽  
Food Intake ◽  
Case History ◽  
Nutritional Assessment ◽  
Pathologic Fracture ◽  
Handicapped Child ◽  
Great Effort ◽  
Spastic Quadriplegia ◽  
History Of ◽  
History Of Pain

CASE HISTORY G.R. is a 7-year-old boy with spastic quadriplegia evident since birth and a seizure disorder for which he currently is being treated with phenobarbitol and phenytoin (diphenylhydantoin). His medical history includes a pathologic fracture of his right femur. At the time of his fracture, a radiograph of his femur was described as "markedly osteoporotic." He is currently being treated with 1200 IU of vitamin D. His diet as presented is balanced with respect to nutrients. Although spillage is not substantial, eating requires great effort, and each meal lasts approximately 1 hour. He is fed breakfast and supper at home by his mother and lunch in school. There is no history of pain with food intake, no vomiting, and no diarrhea. He weighs 14 kg (far below the 5th percentile), and his length is 112 (at the 5th percentile). His weight for height is far less than the 5th percentile. His mother is 157.5 cm (5 ft 2 in) tall and his father is 167.5 cm (5 ft 6 in) tall. His midarm circumference is 154 mm (less than the 5th percentile), his triceps skinfold is 5 mm (5th percentile), and his midarm muscle circumference is 138 mm (less than the 5th percentile).

Understanding Culture

2017 ◽  
Author(s):  
Babette Hellemans
Keyword(s):  
Gender Studies ◽  
Duration Analysis ◽  
International Perspective ◽  
Theoretical Background ◽  
The Arts ◽  
Long Duration ◽  
Historical Investigation ◽  
History Of ◽  
And Gender ◽  
The Relationship

This pioneering textbook explores the theoretical background of cultural variety, both in past and present. How is it possible to study 'culture' when the topic covers the arts, literature, movies, history, sociology, anthropology and gender studies? Understanding Culture examines the evolution of a concept with varying meanings depending on changing norms. Offering a long-duration analysis of the relationship between culture and nature, this book looks at the origins of studying culture from an international perspective. Using examples from the several scholarly traditions in the practice of studying culture, Understanding Culture is a key introduction to the area. It identifies the history of interpreting culture as a meeting point between the long-standing historical investigation of 'humanism' and 'postmodernism' and is a comprehensive resource for those who wish to further their engagement with culture as both a historical and contemporary phenomenon.

scholarly journals Intestinal lymphangiectasia: case report

2019 ◽  
Vol 6 (5) ◽  
pp. 1678
Author(s):  
Reham Mohmmad Aljohnei ◽  
Hawazen Yousef Abdullah Alani
Keyword(s):  
Case Report ◽  
Rare Disease ◽  
Present Report ◽  
Abdominal Distention ◽  
Intestinal Lymphangiectasia ◽  
Peripheral Edema ◽  
Long Duration ◽  
White Spots ◽  
Intestinal Lymphatics ◽  
History Of

Primary intestinal lymphangiectasia (PIL) was first described by Waldmann et al, in 1961. PIL is a rare disease with several hundred reported cases. It is rarely reported in adults because it is presumably a congenital disorder and when present in adults it typically produces a long duration of manifestation such as diarrhea, abdominal distention from ascites, and peripheral edema. This disorder is characterized by markedly dilated intestinal lymphatics, hypoproteinemia, generalized edema, lymphocytopenia hypogammaglobinemia, and immunologic anomalies. The loss of protein into the from dilated intestinal lymphatics leads to the development of hypoproteinemia in these patients and its demonstration is important in the diagnosis of intestinal lymphangiectasia. The disease can be secondary to congenital, secondary or idiopathic defects in the formation of the lymphatic ducts. In the present report, we describe a case of 15 years old female presented to our hospital with history of generalized edema, bilateral hand spasm, and diarrhea. Endoscopy of the patient revealed White spots (dilated lacteals), white nodules, and submucosal elevations were observed. Changes suggestive of the disease includes White villi and/or spots (dilated lacteals), white nodules, and submucosal elevations are observed. Xanthomata’s plaques are often visualized, there are no specific treatments for patients with PIL. treatment of patients with primary intestinal lymphangiectasia involves control of symptoms with the use of dietary, pharmaceutical, and behavioral modifications.

scholarly journals Expansion, retention and loss in the Acyl-CoA Synthetase “Bubblegum” (Acsbg) gene family in vertebrate history

2018 ◽  
Author(s):  
Mónica Lopes-Marques ◽  
André M. Machado ◽  
Raquel Ruivo ◽  
Elza Fonseca ◽  
Estela Carvalho ◽  
...  
Keyword(s):  
Gene Family ◽  
Metabolic Pathways ◽  
Evolutionary History ◽  
Gene Families ◽  
Gene Repertoire ◽  
Physiological Processes ◽  
Complex Lipid ◽  
History Of ◽  
Enzyme Families ◽  
Rate Limiting

AbstractFatty acids (FAs) constitute a considerable fraction of all lipid molecules with a fundamental role in numerous physiological processes. In animals, the majority of complex lipid molecules are derived from the transformation of FAs through several biochemical pathways. Yet, for FAs to enroll in these pathways they require an activation step. FA activation is catalyzed by the rate limiting action of Acyl-CoA synthases. Several Acyl-CoA enzyme families have been previously described and classified according to the chain length of FA they process. Here, we address the evolutionary history of the ACSBG gene family which activates, FA with more than 16 carbons. Currently, two different ACSBG gene families, ACSBG1 and ACSBG2, are recognized in vertebrates. We provide evidence that a wider and unequal ACSBG gene repertoire is present in vertebrate lineages. We identify a novel ACSBG-like gene lineage which occurs specifically in amphibians, ray finned fish, coelacanths and chondrichthyes named ACSBG3. Also, we show that the ACSBG2 gene lineage duplicated in the Theria ancestor. Our findings, thus offer a far richer understanding on FA activation in vertebrates and provide key insights into the relevance of comparative and functional analysis to perceive physiological differences, namely those related with lipid metabolic pathways.

Chemical Methods

1998 ◽  
Author(s):  
Norman Herz ◽  
Ervan G. Garrison
Keyword(s):  
Chemical Change ◽  
Age Determination ◽  
Chemical Processes ◽  
Chemical Methods ◽  
Amino Acid Racemization ◽  
Singular Event ◽  
Archaeological Materials ◽  
History Of ◽  
Absolute Age ◽  
Chemical Dating

Time is nature's way of keeping everything from happening at once" (anonymous). Time is a continuum—we sense this continuum as a succession of events. In archaeological matters it is one of the most salient attributes. To determine time accurately the archaeologist must rely on modern dating techniques. Age determination by chemical methods relies on the constancy or predictability of rates of chemical processes. For instance the oxidation of iron—rust—could be used for dating purposes if one could determine a chemical rate, in this case that of oxidation, that applied to more than the singular event. Unfortunately, the rate of the oxidation of iron is highly variable, being affected by temperature, available moisture, and the particular type of iron (mild, cast, stainless, etc.). Another common chemical change is the patination of certain types of glass. Yet here, too, the process is highly variable, making dating impractical. Still, there have been attempts to use patination and rock "varnish" for archaeological dating, as we shall see. In the main, chemical dating is used to determine relative ages since absolute ages require calibration for each sample and its find site using independent dating measures such as radiometric or dendrochronological techniques. We shall first discuss the relative techniques based on the uptake or decrease in fluorine, uranium, and nitrogen found in bone. This is most appropriate because these chemical techniques played a key role in unmasking one of the most famous frauds in the history of science: Piltdown Man. Next we shall examine the two most accepted chemical processes utilized in absolute age determination, which are based, respectively, on amino acid racemization and obsidian hydration. Finally, we shall examine a few techniques that show some promise for the dating of archaeological materials or deposits, such as those using patination ("varnish") and cation ratios. Our points of reference are those events we view as, in some sense, marking a change in the state of things. Stylistic or formal change in an archaeological facies can be a chronological landmark for the archaeologist and allows us to divide the continuum of time into discrete segments or phases.

The evolutionary history of Nothofagus (Nothofagaceae)

1993 ◽  
Vol 6 (2) ◽  
pp. 111 ◽  
Author(s):  
RS Hill ◽  
GJ Jordan
Keyword(s):  
Parallel Evolution ◽  
Cladistic Analysis ◽  
Long Distance ◽  
Interesting Insight ◽  
Extant Species ◽  
Singular Event ◽  
History Of ◽  
Morphological Differences ◽  
The Relationship

A cladistic analysis of Nothofagus is presented. Comparison of potential outgroups (Fagus and Betulaceae) suggests that Fagus is most satisfactory, but clear morphological differences between it and Nothofagus support the placement of the latter in the monogeneric family Nothofagaceae. The cladistic analysis supports the four subgenera and four extant pollen groups proposed in the most recent revisions and is consistent with the extensive fossil record, although not especially supported by it. The evolution of the deciduous or evergreen habit. so long considered a singular event of importance in Nothofagus, probably occurred several times, and is an example of parallel evolution. Resolution within subgenera is not high in most cases, but subgenus Lophozonia offers a particularly interesting insight into the relationship among extant species and the role of rare long distance dispersal across significant ocean barriers in Nothofagus biogeography. More data are required to refine the phylogeny.

Psoriasis and Psoriatic Arthritis in Peruvian Aborigines: A Report from the GRAPPA 2011 Annual Meeting

2012 ◽  
Vol 39 (11) ◽  
pp. 2216-2219 ◽  
Author(s):  
SERGIO M.A. TOLOZA ◽  
OSCAR VEGA-HINOJOSA ◽  
VINOD CHANDRAN ◽  
RAFAEL VALLE ONATE ◽  
LUIS R. ESPINOZA
Keyword(s):  
Psoriatic Arthritis ◽  
Aboriginal People ◽  
Clinic Visit ◽  
European Ancestry ◽  
Drug Of Choice ◽  
Long Duration ◽  
Established Disease ◽  
History Of ◽  
Genetic And Environmental Factors

Objective.To determine the presence of psoriasis and psoriatic arthritis (PsA) in aboriginal people living in the Andean Mountains of Peru.Methods.Consecutive patients with psoriasis and PsA attending an arthritis clinic in Juliaca, Puno, Peru, located 3824 m above sea level were examined. The CASPAR (ClASsification of Psoriatic ARthritis) criteria were used for classification of PsA. Diagnosis of psoriasis was confirmed by a dermatologist.Results.Seventeen patients [11 (65%) men and 6 (35%) women] fulfilled classification criteria for PsA; one patient was of European ancestry and is not included in this report. Of the 16 aboriginal patients in this report, 5 were natives of Quechua ancestry and one was native Aymara. At the time of their first clinic visit, no native patient with PsA had a family history of psoriasis or PsA, and all patients exhibited an established disease of long duration and severity. Methotrexate was the drug of choice for all patients; 2 patients are currently receiving biological therapy.Conclusion.Contrary to what has been reported in the literature, both psoriasis and PsA are present in aboriginal people from the Andean Mountains of Peru. More studies are needed to further define the phenotype of these disorders, as well as the pathogenetic role of genetic and environmental factors.

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