A Prehispanic Irrigation System near Santa Clara Xalostoc in the Basin of Mexico

1977 ◽  
Vol 42 (4) ◽  
pp. 582-588 ◽  
Author(s):  
William T. Sanders ◽  
Robert S. Santley
Keyword(s):  
Methodological Problem ◽  
Irrigation System ◽  
Cultural Ecology ◽  
Theoretical Issue ◽  
Central Mexico ◽  
Canal System ◽  
Basin Of Mexico ◽  
Ideal Situation ◽  
Canal Systems

AbstractA major theoretical issue in studies of the cultural ecology of Central Mexico has been the role of irrigation in the evolution of the state in that area. A major methodological problem has been the location and dating of prehistoric canal systems. A recent discovery near Xalostoc, of a stratified canal system (representing three distinct periods) in the exposed profiles of contemporary adobe extraction pits, offers an ideal situation for dating of prehistoric canals. All three are apparently Pre-Coyotlatelco in date and the settlement history suggests that some of them are contemporary with Teotihuacan.

A Middle Formative Irrigation System near Santa Clara Coatitlan in the Basin of Mexico

1982 ◽  
Vol 47 (1) ◽  
pp. 133-144 ◽  
Author(s):  
Deborah L. Nichols
Keyword(s):  
Control Systems ◽  
Methodological Problem ◽  
Irrigation System ◽  
Theoretical Issue ◽  
Water Control ◽  
Settlement Systems ◽  
Excellent Opportunity ◽  
Basin Of Mexico ◽  
Middle Formative ◽  
The Relationship

A major theoretical issue in studies of prehistoric societies in the Basin of Mexico concerns the relationship between irrigation and the development of prehistoric settlement systems. Locating and dating the remains of prehistoric water control systems, however, presents a major methodological problem. The discovery of a series of stratified prehistoric canals in the exposed profiles of contemporary borrow pits near Santa Clara Coatitlan provided an excellent opportunity for dating a prehistoric irrigation system. Results of recent excavations, reported on in this paper, demonstrate that these canals are part of a middle Formative floodwater irrigation system, which is the earliest confirmed evidence, to date, for the use of irrigation in the Basin of Mexico.

scholarly journals Comparative Analysis of the Smear Layer Removal Capability between EndoVac and Endoactivator Endodontic Irrigation Systems at the Root Canal System and Isthmus: A Micro-Computed Tomography Analysis

2020 ◽  
Vol 10 (20) ◽  
pp. 7033
Author(s):  
Vicente Faus-Llácer ◽  
Mauricio Luna-Roa ◽  
Ignacio Faus-Matoses ◽  
Celia Ruiz-Sánchez ◽  
Álvaro Zubizarreta-Macho ◽  
...  
Keyword(s):  
Root Canal ◽  
Irrigation System ◽  
Smear Layer ◽  
Micro Computed Tomography ◽  
Canal System ◽  
Layer Removal ◽  
Ct Analysis ◽  
Canal Systems ◽  
Root Canal System ◽  
Endodontic Irrigation

The aim of this comparative study is to analyze the efficacy of EndoVac and Endoactivator endodontic irrigation systems for removing the endodontic smear layer present in the coronal, middle, and apical root third of the root canal system (RCS) and the isthmus from mesial roots from the first lower molar teeth using micro-computed tomography (micro-CT) analysis. The study was performed on 40 mesial roots that were randomly assigned to the following groups: Group A, EndoVac endodontic irrigation system (EV) (n = 10); Group B, Endoactivator endodontic irrigation system (EA) (n = 10); Group C, Root canal systems performed with F2 ProTaper Gold endodontic rotary system but not irrigated (Positive control) (n = 10); Group D, Root canal systems not performed or irrigated (Negative control) (n = 10). The samples were exposed to micro-CT analysis and the mesial roots were segmented using an advanced image segmentation technique based on partial differential equations (ROI: 10 × 10 × 10 mm) and the root canal systems and isthmus were reconstructed at a resolution of 25 microns per voxel. The EA study group showed statistically significant different residual endodontic smear layer volume (0.48 ± 0.24 mm3) compared to the EV study group (0.18 ± 0.15 mm3) (p = 0.016). The EV endodontic irrigation system performed a higher smear layer removal at coronal and middle root thirds, compared to the EA endodontic irrigation system; however, the EA endodontic irrigation system performed a higher smear layer removal at the apical root third, compared to the EV endodontic irrigation system.

Conflict in the Modern Teotihuacan Irrigation System

1962 ◽  
Vol 4 (4) ◽  
pp. 494-524 ◽  
Author(s):  
René Millon ◽  
Clara Hall ◽  
May Díaz
Keyword(s):  
Irrigation System ◽  
Central Mexico ◽  
Northwestern Part ◽  
Central Plateau ◽  
Basin Of Mexico ◽  
Middle America ◽  
Strategic Role ◽  
Special Concern ◽  
Irrigation Agriculture ◽  
Semi Arid

In recent years a number of investigators have been concerned with the antiquity of irrigation agriculture in central Mexico and its possible relationship to processes of social and political differentiation in the ancient urban civilizations of that region. Because of its strategic role in the prehistory of Middle America, attention has centered on the Basin of Mexico in the Mexican central plateau. The semi-arid Valley of Teotihuacan, in the northwestern part of the Basin, has been of special concern because it was the locus of the enormous city of Teotihuacan, one of the most powerful and influential centers in Middle America during a large part of the first millenium of the Christian era. Studies to date have dealt largely with historical and archaeological evidence bearing on this problem.

scholarly journals The Role of Intuition and Prognostic Risk Assessment Regarding the Leave of Offenders with Mental Disorders

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
C. Schmitt
Keyword(s):  
Risk Assessment ◽  
Mentally Ill ◽  
Psychological Factors ◽  
Methodological Problem ◽  
German Law ◽  
Decision Makers ◽  
Mentally Ill Offenders ◽  
Rare Occurrence ◽  
German State

The granting of leave during terms of imprisonment plays an important part in the treatment of mentally ill offenders. According to German law, leave is to be granted in those cases where the abuse of this privilege or an attempt to flee can be negated. These regulations also, however, imply that the risk assessment of a patient's offence-related recidivism can not be the only criterion for the granting of leave.So far, there have only been few studies about the prognostic risk assessment of the general abuse of leave. This is rather astonishing, as the granting of leave outside the institutional grounds, in particular, is a decision which often leaves those responsible fraught with anxiety. Furthermore, the abuse of a granted temporary release can lead to severe consequences on various levels.As part of a study to be conducted in the German state of Rhineland-Palatinate, decisions about granting leave are to be analyzed and possible predictors of the abuse of leave are to be examined.It is assumed that the abuse of leave is likely to be motivated by the conditions of particular situations and can primarily be explained by normal psychological factors.However, it should be pointed out that, as the abuse of leave is such a rare occurrence, it poses a significant methodological problem. The criterion to be examined therefore needs to be exactly defined and particular attention must be paid to achieve an adequately high interreliability of the decision makers.

scholarly journals Monitoring of reproductive health in the striped catfish Pangasianodon hypophthalmus (Sauvage, 1878) from the Saen Saep Canal, Thailand

2021 ◽  
Vol 20 (1) ◽  
pp. 61-72
Author(s):  
Thawanrat Puttipong ◽  
◽  
Sinlapachai Senarat ◽  
Jes Kettratad ◽  
Chitchai Chantangsi ◽  
...  
Keyword(s):  
Reproductive Health ◽  
Industrial Effluents ◽  
Reproductive Status ◽  
Polluted Water ◽  
Canal System ◽  
Vacuolar Degeneration ◽  
Pangasianodon Hypophthalmus ◽  
Eosinophilic Cytoplasm ◽  
Canal Systems ◽  
Striped Catfish

Khlong Saen Saep is one of the most important and large canal systems in Bangkok, Thailand. However, the emergence of heavily polluted water has occasionally been reported due to the domestic sewage and industrial effluents discharged into the system. This situation may affect the reproductive status of aquatic lives residing in this canal. To evaluate the reproductive status of the canal inhabitant, the striped catfish Pangasianodon hypophthalmus (Sauvage, 1878)—a common dweller of the Saen Saep Canal—was collected from two selected stations, the Bumpen Nua Temple and the Kamalun Islam Mosque. The fish gonads were then anatomically and histologically examined. The results indicated that neither parasites nor ovary with external abnormality were found. Nevertheless, several histological alterations were detected, including vacuolar degeneration of previtellogenic oocytes, accumulation of melanomacrophage centers (MMCs), and atretic oocytes. Moreover, severe histopathological changes, such as the eosinophilic cytoplasm of spermatogonia, MMCs, blood congestion, and syncytium of spermatozoa, were observed in the fish testis. Our study suggested that the environmental stress and pollutions previously reported from the Saen Saep Canal possibly underpin the gonadal impairments of P. hypophthalmus examined and may have adverse impact on the reproductive health of others living in this canal system

scholarly journals Evaluation of Interference of Calcium Hydroxide-based Intracanal Medication in Filling Root Canal Systems

2011 ◽  
Vol 12 (5) ◽  
pp. 368-371 ◽  
Author(s):  
Matheus Melo Pithon ◽  
Deyla Duarte Vilela ◽  
Manoel Matos Neto ◽  
Alexandre Mascarenhas Villela
Keyword(s):  
Calcium Hydroxide ◽  
Clinical Significance ◽  
Root Canal ◽  
Canal System ◽  
Root Canals ◽  
Anterior Teeth ◽  
Knowing That ◽  
Group I ◽  
Canal Systems ◽  
Root Canal System

ABSTRACT Aim To evaluate the interference of the intracanal medication Calen® (SSWhite, São Paulo, Brazil) on the filling of simulated lateral canals. Materials and methods Twenty human anterior teeth were used. Before the endodontic filling procedures the access of cavity was made, and after this root canals were made in all the teeth to simulate the presence of lateral canals. After preparation, the teeth were randomly divided into two groups (n=10). In group I, the root canal system was filled directly after chemicalmechanical preparation; in group II, endodontic treatment was performed in multiple sessions, and after preparation the calcium hydroxide-based intracanal medication Calen® was inserted. After the period of 7 days, the root canals were vigorously irrigated and then they were filled. Next, the teeth were radiographed to verify the quality of the filling. Results The results demonstrated that the teeth treated in a single session, without calcium hydroxide medication, presented 47 canals out of 60 with radiographic evidence of filling, whereas the teeth in which intracanal medication was used, only 07 presented a radiographic image compatible with filling (p < 0.05). Conclusion The use of the calcium hydroxide-based medication Calen made it difficult to obtain a hermetic filling of the root canal system. Clinical significance The clinical significance of this work basing on the fact that once the dentist knowing that property obliteration of calcium hydroxide can be taken care when they are used in the presence of lateral canals. How to cite this article Vilela DD, Neto MM, Villela AM, Pithon MM. Evaluation of Interference of Calcium Hydroxide-based Intracanal Medication in Filling Root Canal Systems . J Contemp Dent Pract 2011;12(5):368-371.

The role of aerocosmic research in metallogenic prediction (on the example of antimony-mercury ore formation deposits in Azerbaijan)

2020 ◽  
Vol 02 (03) ◽  
pp. 55-60
Author(s):  
Zaki Abdulla Valiyev ◽  
Keyword(s):  
Total Mercury ◽  
Ore Formation ◽  
Aerospace Research ◽  
The Earth ◽  
Ideal Situation ◽  
Metallogenic Prediction ◽  
Key Words Mercury ◽  
Deep Fractures ◽  
The Ideal

Mercury degassing is a global process. In geological development, it begins with the formation of deep fractures that can penetrate the great depths of the mantle. As the linearity lengthens, the temporal degassing and intensity of mercury weaken this connection with the depths of its individual parts and the Earth, or the period of strengthening of this connection will vary depending on the development of the characteristics observed. The concentration of mercury and antimony-mercury ores along the outer frame of circular and oval and other structures can most likely be explained by the Earth's total mercury degassing. In our opinion, the ideal situation is the junction of circular, oval, and other structures with linear nodes, where industrially important deposits of minerals can be formed. Key words: mercury, aerospace research, metallogenic prediction, minerals

Sign in / Sign up

Export Citation Format

Share Document