scholarly journals ‘Fire hardening’ spear wood does slightly harden it, but makes it much weaker and more brittle

2016 ◽  
Vol 12 (5) ◽  
pp. 20160174 ◽  
Author(s):  
Antony Roland Ennos ◽  
Tak Lok Chan
Keyword(s):  
Mechanical Properties ◽  
Side Effect ◽  
Hardness Test ◽  
Hunter Gatherers ◽  
Negative Side ◽  
Negative Side Effect ◽  
Impact Tests ◽  
Hardening Process ◽  
Work Of Fracture

It is usually assumed that ‘fire hardening’ the tips of spears, as practised by hunter–gatherers and early Homo spp., makes them harder and better suited for hunting. This suggestion was tested by subjecting coppiced poles of hazel to a fire-hardening process and comparing their mechanical properties to those of naturally seasoned poles. A Shore D hardness test showed that fire treatment slightly increased the hardness of the wood, but flexural and impact tests showed that it reduced the strength and work of fracture by 30% and 36%, respectively. These results suggest that though potentially slightly sharper and more durable, fire-hardened tips would actually be more likely to break off when used, as may have been the case with the earliest known wooden tool, the Clacton spear. Fire might first have been used to help sharpen the tips of spears, and fire-hardening would have been a mostly negative side effect, not its primary purpose.

Multicolored Blindfolds

2017 ◽  
Vol 9 (7) ◽  
pp. 825-834 ◽  
Author(s):  
Seval Gündemir ◽  
Adam D. Galinsky
Keyword(s):  
Racial Discrimination ◽  
Intergroup Relations ◽  
Side Effect ◽  
Racial Minorities ◽  
Organizational Diversity ◽  
Negative Side ◽  
Objective Information ◽  
Negative Side Effect ◽  
Multicultural Diversity

Past studies have found that multicultural approaches to diversity can reduce prejudice and stimulate positive intergroup relations. The current research explored a possible negative side effect of multiculturalism: whether organizational diversity structures geared toward multiculturalism can conceal racial discrimination and delegitimize racial discrimination claims. Three studies found that, even when objective information was indicative of discrimination, both Whites and racial minorities perceived organizations which had diversity policies emphasizing multiculturalism as more fair toward minorities. This perception of (false) fairness led individuals to perceive less racial discrimination and to view claims of racial discrimination against that organization as less legitimate. Furthermore, we found that organizational multiculturalism and externally granted diversity awards both produced a (false) fairness effect. The results suggest an irony of multicultural diversity structures: They can create a false fairness effect that conceals and delegitimizes discrimination.

Study on the Performance of a Novel Shrinkage Reducing Admixtures (SHSRA) of Concrete

2011 ◽  
Vol 117-119 ◽  
pp. 1190-1194
Author(s):  
Xia Hong Zhang ◽  
Chao Li ◽  
Ying Fei Wang ◽  
Sheng Nian Wang
Keyword(s):  
Heat Release ◽  
Side Effect ◽  
Drying Shrinkage ◽  
Hydration Rate ◽  
Negative Side ◽  
Negative Side Effect ◽  
Strength Tests ◽  
Shrinkage Reducing Admixture ◽  
Dry Shrinkage ◽  
Shrinkage Reducing Admixtures

A novel Shrinkage reducing admixture (SHSRA) has been developed. Several tests including the workability , drying shrinkage，the hydration heat and strength tests were carried out to evaluate the effect of SHSRA on the performance of the concrete specimens. The results showed that the presence of SHSRA induced a significant reduction in dry shrinkage by up to 40% after 28 days. The SHSRA could cause decreases in both hydration rate and heat release of hydration of cementing materials which can attribute to reducing the risk of cracking. Besides, no negative side effect on the concrete workability and the later strength has been observed with the addition of the SHSRA.

scholarly journals Preconditioning is a method that may reduce the negative side-effect of pneumoperitoneum

2010 ◽  
Vol 2 (3) ◽  
pp. 115-120 ◽  
Author(s):  
Szaniszló Z. Jávor ◽  
K. Shanava ◽  
E. Hocsák ◽  
M. Kürthy ◽  
J. Lantos ◽  
...  
Keyword(s):  
Side Effect ◽  
Negative Side ◽  
Negative Side Effect

Introduction

2021 ◽  
pp. xiv-19
Author(s):  
Hasia R. Diner
Keyword(s):  
Side Effect ◽  
Historical Thinking ◽  
Negative Side ◽  
Negative Side Effect ◽  
Jewish Diaspora ◽  
Territorial Sovereignty ◽  
History Of ◽  
The Impact

Not only has diaspora been one of the key realities of the long history of the Jews, but it also has dominated historical thinking about that phenomenon. Historians have divided over the origins of the Jewish diaspora, debating how much it reflected the negative forces of expulsion and persecution or how much new opportunities in places more conducive to their security and prosperity opened up to them. Historians have also debated the impact of diaspora as either a source of strength and creativity as opposed to a clearly negative side effect of the lack of territorial sovereignty. Either way, the history of the Jews cannot and has not been told without an understanding of the centrality of diaspora.

Induction of longevity in primed seeds

1999 ◽  
Vol 9 (1) ◽  
pp. 49-53 ◽  
Author(s):  
G.T. Bruggink ◽  
J.J.J. Ooms ◽  
P. van der Toorn
Keyword(s):  
Water Stress ◽  
Temperature Stress ◽  
Desiccation Tolerance ◽  
Side Effect ◽  
Temperature Dependent ◽  
Negative Side ◽  
Negative Side Effect ◽  
Optimal Duration ◽  
Reduced Time ◽  
Germinated Seeds

AbstractPriming of seeds is generally intended to reduce time to germination, often leading to improved emergence. However, as a negative side effect, priming reduces longevity of seeds. We studied the possibilities to obtain primed seeds with reduced time to germination but with longevity similar to that of untreated seeds. For several species tested we found that the desired longevity could be obtained by keeping the seeds, after a priming treatment, under a mild water and / or temperature stress for a period of several hours to days. Time to germination did not increase again due to such a treatment. Optimal duration and degree of water stress were strongly temperature dependent. The methods applied to obtain primed seeds without loss of longevity are very similar to those used to induce desiccation tolerance in germinated seeds.

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