Gastric acid level of humans must decrease in the future

Proton pump inhibitors strongly inhibit gastric acid production,but digestion problems do not generally arise.We can intake almost ordinary food even after total gastrectomy.Small intestine itself can digest and absorb food using various digestive enzymes without digestion in the stomach.The pH level of gastric acid in humans is much lower than that of most animals,and very close to that of carrion-eating animals called scavengers.It is assumed that ancient humans became bipedal approximately 4 million years ago.It was difficult for humans,who just started unstable bipedal locomotion,to catch quadrupedal-walking animals that can move faster,without special hunting tools.They may have eaten remaining carcasses,which is mainly the leftovers of carnivora species,as animalderived food.The benefit to produce a volume of gastric acid for humans is carrion eating,in which disinfection by gastric acid is important.Humans produce a high concentration of gastric acid to enable consumption of a diet containing some bacteria and support this lifestyle by consuming significant energy to protect themselves from gastric acid.Now,the opportunity for strong deleterious bacteria to enter the gastrointestinal tract has decreased because of the organized clean environment.If this hygienic environment is maintained for a long time,our gastric acid level must be decreased gradually.

Ancient River in the Houjiayao Site, Nihewan Basin and Its Environmental Archaeological Significance

Lying on the northwest of Nihewan Basin, Houjiayao Site was discovered 40 years ago. But there is still a controversy about the existence age and the living environment of Houjiayao ancient human. Based on the geological investigations, electrical resistivity sounding and altitude measuring, authors of this paper attempt to do a research on stratigraphic structure and the development of the ancient river in Houjiayao Site, and to interpret the above problems. The results are as follows:(1) An ancient river, which came from Xionger Mountain in the north of the Site, developed in Houjiayao Site, and its width was more than 1 km. The ancient river formed before 240 ka B.P., and disappeared in the early stage of the late Pleistocene, and its developing history ran through the entire living stage of Houjiayao ancient human.(2) The Site cultural relics were not buried in the lacustrine facies, but in the oxbow lake sediments of the ancient river and clay layer which laid on the oxbow lake sediments unconformably during the period of 224-161 ka B.P., and it indicated that the Houjiayao ancient people lived here for as long as 60 ka years.(3) The Site looked like a wide armchair faced southeast, and it provided a relatively mild and comfortable environment for the ancient. The ancient river provided the ancient human with water, and the superior eco-environment also provided plentiful food for the ancient human. Xionger Mountain was not only the source of the ancient river, but also the producing area for high quality stone materials. The old river carried stone materials to the Site, making it easier to make stone implements. Hence, the ancient human, who lived in cold weather, were more likely to choose better habitats such as the Houjiayao Site near the ancient river.(4) The old river embedded in the lacustrine facies, so the content of silt was high, and it was feculent. And the water of the oxbow lake near Houjiayao Site was clear and slow. What's more, with plentiful plants, the oxbow lake was a preferred place for all kinds of animals to get food and water. But the geomorphologic features of this oxbow lake made it hard for animals to escape when faced with dangerous situations. So ancient human had a better chance to get food from hunting near the oxbow lake than in other areas.

Geochemical analysis of multi-element in archaeological soils from Tappe Rivi in Northeast Iran

Multi-element analysis in historical sites is a major issue in archaeological studies;however,this approach is almost unknown among Iranian scholars.Geochemical multi-element analysis of soil is very important to evaluate anthropogenic activities.The aim of this study consists of assessing the potential usefulness of multi-elemental soil analysis,obtained by Analytical Jena atomic absorption spectrophotometer(AAS) and ICP-MS,to recognize ancient anthropogenic features on the territory of Tappe Rivi(North Khorasan,Iran).For that purpose,a total of 80 ancient soil samples were sampled from each soil horizon and cultural layer.The research involved Fe,Al,Cd,Cu,Ni,Co,Cr,Pb,and P which trace element samples were extracted according to the International Standard ISO 11466 and phosphorus samples by Olsen method.Besides,the contamination of the soils was assessed based on enrichment factors(EFs) by using Fe as a reference element.This geochemical/archaeological approach highlights that the content of most elements in the Parthian and Sassanid ages were significantly higher than the contents of the elements in other zones,which shows that by the development of the eras,the content of the elements has also increased.Also,the accumulation of metals in the Rivi site was significantly higher than in the control area.Among the sampled zones,enrichment factor(EF) indicated that the enrichment of Cu and phosphate at the Parthian and Sassanid had the highest content.This result is important because it shows that the amount of metals and human activities are directly related to each other during different ages.

Occlusal tooth wear in human sculls of antique period from Vendenis and Municipium Dardanorum DD, Kosovo

Aim: To describe the presence, frequency of attrition in permanent dentition of human skulls from two ancient archeological locations. Aims: To determine the rate of attrition using a specific quantitative and qualitative method. Methods: Twenty one human skulls from two ancient archeological necropolises (Vendenis and Municipium Dardanorum DD) were included in the analysis of samples for this study. A total of 498 teeth were present in all human skulls. The skulls (with their accompanying teeth) were then divided into groups according to locality of origin, age and sex. Macroscopic (observational) analysis of the teeth relied on inspection and exploration of the teeth in their totality. The classification system that was used to rate tooth wear was Tooth Wear Index (TWI). Statistical analysis used: Chitest for small samples was used to evaluate the observations obtained from the study. Multiple Logistic Regression Analysis was not performed due to the small number of teeth and the content of zero values in respective age groups. Results: The results show that out of total 498 teeth, 89.35% had attrition and 10.65% had no attrition or Grade 0 TWI. 21.48% were Grade 1, 28.71% Grade 2, 26.90% Grade 3, 7.42% Grade 4 and 4.81% Grade 5. Conclusions: Grade 2 and higher rate of attrition, was predominantly present in first permanent molars.

Exploration of the Relationship between Geographical Environment and Human Diseases in Ancient China

The Yellow Emperor's Classic of Internal Medicine (黄帝内经素问Huangdi Neijing Suwen), created in the Warring States period (475 to 221 BC) described a phenomenon whereby the eastern, western, northern, southern, and central regions were liable to different diseases. It brought forward the principle of treatment in accordance with local conditions. Lv's Spring and Autumn Annals, Huai Nan Tzu (Huainanzi), and the Regiment of Health (Yangshenglun) in the Qin, Han, Wei, Jin, and Southern and Northern Dynasties all describe regional diseases such as goiter (endemic goiter) and yellowish teeth (dental fluorosis) as being caused by geologic and climatic factors. Zhang (miasma), first mentioned in the Han Dynasty, was considered related to the summer heat and dampness particular to the geographical environment of the south. Zhang was further associated with malaria in the Jin Dynasty. General Treatise on the Etiology and Symptomology of Diseases (Zhubingyuanhou Lun), in the Sui Dynasty, held that as a type of poisonous gas, Zhang was the predisposing cause of malaria, seasonal disease, and barbiers, among other conditions. General Guide (Zhinan Zonglun), in the Southern Song Dynasty, regarded Zhang malaria as a separate disease. Healthy Prescription in the Southern Wuling District (Lingnan Weisheng Fang), in the late Song and early Yuan Dynasties, explicitly put forward the concepts of cold Zhang, hot Zhang, and lockjaw Zhang. Guidelines for Treatment of Zhang Malaria (Zhangnue Zhinan), in the Ming Dynasty, maintained that cold Zhang was equivalent to malaria, while hot Zhang and lockjaw Zhang were equivalent to cold damage, the latter of which can be treated by prescriptions for cold damage. Records on Zhang gas and Zhang disease decreased during the Ming and Qing Dynasties.

Ancient Skull May Rewrite Human History

The discovery of fossilized human remains at an archeological dig may solve debate over the origins of the Chinese