The negative stain is particularly useful for determining cell size and arrangement. It can also be used to stain cells that are too delicate to be heat-fixed. We use nigrosin as our negative stain. Nigrosin is an acidic stain.
To 2040 A.D. Until late 2006, global temperatures were more than a degree Fahrenheit warmer when compared to the 20th Century average. From August of 2007 through February of 2008, the Earthâs mean temperature dropped to near the 20th Century average of 57 degrees.
Last year was the thirty-seventh consecutive year of above-normal global temperature. According to data from NASA, the global temperature in 2013 averaged 58.3 degrees Fahrenheit (14.6 degrees Celsius), roughly a degree warmer than the twentieth-century average. Since the dawn of agriculture 11,000 years ago, civilization has enjoyed a relatively stable climate.