The conventional wisdom has been challenged recently that microblades with handles are only tools for hunting and gathering in the Neolithic Age. Some scholars argued that microblades actually played an important part...The conventional wisdom has been challenged recently that microblades with handles are only tools for hunting and gathering in the Neolithic Age. Some scholars argued that microblades actually played an important part in the early agricultural development in the Neolithic. However, both of these opinions lacked direct evidence. Environmental scanning electron microscopy (ESEM) is used to analyze the residues of the bone-handled microblade excavated at the Shangzhai site in Pinggu, Beijing. The ESEM observation and EDX analysis show that at the edge of this bone-handled microblade are Ca, P, C, O or C, N, O, etc, which provide direct evidence for determining its function, namely that this microblade may have been dealt with animals. In addition, there was a layer of glue at the back of the microblade with barium and zinc salt distributed evenly in it, this new discovery sheds new light on adhesive technology in ancient China.展开更多
Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,...Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the TP.The timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains controversial.In this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior TP.Our analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North China.Using Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 ka.This date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the TP.Taken together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.展开更多
<strong>Background and Objective:</strong> The aesthetic products’ safety should not be neglected to the detriment of the market. This study aimed to evaluate the mutagenic potential of commercial inks. I...<strong>Background and Objective:</strong> The aesthetic products’ safety should not be neglected to the detriment of the market. This study aimed to evaluate the mutagenic potential of commercial inks. It was formulated with organic (P1) and inorganic (P2) pigments for eyebrows microblading using a validated method by regulatory agencies, the <em>Salmonella</em>/microsome assay, to assure the safety of use. <strong>Methods:</strong> The assay was carried out in three steps: preliminary toxicity, medium without (-S9), and presence (+S9) of metabolic activation. The strains, auxotrophic to histidine (His-) TA97a, TA98, TA100, and TA102, were exposed to both types of inks, in triplicate, compared to negative and positive controls. Data were statistically analyzed, and values with mutagenic index ≥ 2.0 were indicative of mutagenicity. <strong>Results:</strong> The inks with organic (P1) and inorganic (P2) pigments were not toxic to TA98 and TA100 S. <em>typhimurium</em> tester strains, even at concentrations applied in humans. Both inks were not mutagenic either in the absence or presence of metabolic activation in the tested concentrations, including that applied in humans. The assay showed that P1 and P2 were not direct (-S9) or indirect (+S9) mutagens as commercially formulated. <strong>Conclusions:</strong> These results indicate that applying these inks on organisms with microsomal enzymes, including humans, is safe since no compound in the inks became more toxic to induce the bacterial reverse mutation.展开更多
基金supported by National Social Science Foundation of China (Nos.08BKJ002 and 07KG001)Major Projects of the Humanities and Social Bases of Ministry of Education (Grant No.05JJD78002)+1 种基金"Eleventh Five-Year Plan" Project of the Philosophy and Social Sciences of Beijing Grant Grant (Grant No.06AALS002)Horizontal Project "East Lake stone disease investigation and countermeasures"
文摘The conventional wisdom has been challenged recently that microblades with handles are only tools for hunting and gathering in the Neolithic Age. Some scholars argued that microblades actually played an important part in the early agricultural development in the Neolithic. However, both of these opinions lacked direct evidence. Environmental scanning electron microscopy (ESEM) is used to analyze the residues of the bone-handled microblade excavated at the Shangzhai site in Pinggu, Beijing. The ESEM observation and EDX analysis show that at the edge of this bone-handled microblade are Ca, P, C, O or C, N, O, etc, which provide direct evidence for determining its function, namely that this microblade may have been dealt with animals. In addition, there was a layer of glue at the back of the microblade with barium and zinc salt distributed evenly in it, this new discovery sheds new light on adhesive technology in ancient China.
基金supported by the National Key Research and Development Project of China(Grant No.2021YFC1523603)the Second Tibetan Plateau Scientific Expedition and Research(Grant No.2019QZKK0601)+1 种基金the National Natural Science Foundation of China(Grant Nos.42072033&41977380)the National Social Science Foundation of China(Grant Nos.23&ZD268&21@WTK001)。
文摘Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the TP.Few microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the TP.The timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains controversial.In this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior TP.Our analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North China.Using Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 ka.This date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the TP.Taken together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.
文摘<strong>Background and Objective:</strong> The aesthetic products’ safety should not be neglected to the detriment of the market. This study aimed to evaluate the mutagenic potential of commercial inks. It was formulated with organic (P1) and inorganic (P2) pigments for eyebrows microblading using a validated method by regulatory agencies, the <em>Salmonella</em>/microsome assay, to assure the safety of use. <strong>Methods:</strong> The assay was carried out in three steps: preliminary toxicity, medium without (-S9), and presence (+S9) of metabolic activation. The strains, auxotrophic to histidine (His-) TA97a, TA98, TA100, and TA102, were exposed to both types of inks, in triplicate, compared to negative and positive controls. Data were statistically analyzed, and values with mutagenic index ≥ 2.0 were indicative of mutagenicity. <strong>Results:</strong> The inks with organic (P1) and inorganic (P2) pigments were not toxic to TA98 and TA100 S. <em>typhimurium</em> tester strains, even at concentrations applied in humans. Both inks were not mutagenic either in the absence or presence of metabolic activation in the tested concentrations, including that applied in humans. The assay showed that P1 and P2 were not direct (-S9) or indirect (+S9) mutagens as commercially formulated. <strong>Conclusions:</strong> These results indicate that applying these inks on organisms with microsomal enzymes, including humans, is safe since no compound in the inks became more toxic to induce the bacterial reverse mutation.
