What's the difference between chert and tool?

Chert


Definition:

  • (n.) An impure, massive, flintlike quartz or hornstone, of a dull color.

Example Sentences:

  • (1) Occurrence of well-preserved rod-shaped and coccoid bacteria in the Precambrian Gunflint chert (1.9 x 10(9) years old) has been demonstrated by electron microscopy.
  • (2) In order to evaluate the degree of morphological preservation of erythrocytes in bloodstains, an accidental human blood smear on white chert and several experimental bloodstains on hard substrates (the same stone-white chert; another type of stone-graywacke; a non-stone support-stainless steel), were stored in a room, in non-sterile and fluctuating conditions, for lengths of time ranging from 3 to 18 months.
  • (3) Large amounts of well preserved microfossils have been reported from the cherts of the Upper Proterozoic of the Bohemian Massif (Middle Europe).
  • (4) Two billion year old black chert lenses from the Duck Creek formation, northwestern Western Australia, contain abundant organically preserved microorganisms which are morphologically similar to fossils of approximately the same age from the Gunflint formation, Ontario.

Tool


Definition:

  • (n.) An instrument such as a hammer, saw, plane, file, and the like, used in the manual arts, to facilitate mechanical operations; any instrument used by a craftsman or laborer at his work; an implement; as, the tools of a joiner, smith, shoe-maker, etc.; also, a cutter, chisel, or other part of an instrument or machine that dresses work.
  • (n.) A machine for cutting or shaping materials; -- also called machine tool.
  • (n.) Hence, any instrument of use or service.
  • (n.) A weapon.
  • (n.) A person used as an instrument by another person; -- a word of reproach; as, men of intrigue have their tools, by whose agency they accomplish their purposes.
  • (v. t.) To shape, form, or finish with a tool.
  • (v. t.) To drive, as a coach.

Example Sentences:

  • (1) Spectral analysis of spontaneous heart rate fluctuations, a powerful noninvasive tool for quantifying autonomic nervous system activity, was assessed in Xenopus Laevis, intact or spinalized, at different temperatures and by use of pharmacological tools.
  • (2) The HTCA is promising as a potential tool for studying the biology of tumors.
  • (3) But both for malaria and Aids we’re seeing the tools that will let us do 95-100% reduction.
  • (4) These studies demonstrate the potential of ICAM-1 transfectants as tools for analysis of the role of ICAM-1 in lymphoid adhesion.
  • (5) This method can characterize reliably flavivirus field isolates at the molecular level without extensive virus propagation and molecular cloning, and will be a valuable tool for molecular epidemiological studies.
  • (6) The basic principle of the resonant tool, its adaptation for surgery, the experimental results of its use in animals, and clinical experience are reported.
  • (7) Colloidal gold immuno-electron microscopy is a powerful tool for defining antigenicity at the subcellular level.
  • (8) A diversity of serogroups and toxigenicity was a general finding, however, strains found in the proximal gut were also cultured from the rectum, indicating that faecal specimens would be a valid tool in investigating the role of these organisms in SIDS cases compared with healthy controls.
  • (9) SR 42128 is a potent and long-acting tool for studying the role of the renin angiotensin system in primates and humans.
  • (10) In this study we propose a method for the analysis of the relationship between heart rate changes and respiration as a possible diagnostic tool for cardiac autonomic damage.
  • (11) However LHRH agonists alone or in combination with ovarian steroids are of potential value as a research tool.
  • (12) These findings demonstrate that heteroantisera can provide an additional important tool for dissecting the heterogeneity of T-cell leukemias and for relating them to more differentiated normal T cells.
  • (13) This model provides a standard nonoperative approach for the induction of intestinal ischemia in dogs and could be a valuable tool in the study of intestinal ischemia.
  • (14) Before we embark on the next steps of the global technological revolution, we must ensure that the most basic of online tools are accessible to all.
  • (15) This ion-selective microelectrode may show promise as a useful tool for the determination of intracellular bile salt activity.
  • (16) Axotomy should be a useful tool for determining which other neurotransmitter receptors are produced by facial motoneurons and efferent neurons in other cranial nerve nuclei.
  • (17) Given that patient preferences constitute a central concept within the framework of HRQL, further empirical evaluation of utility measures of preference is fundamental to improving the HRQL measurement tool-kit.
  • (18) This study also demonstrates that pulsed-field gel electrophoresis is a powerful new tool for the analysis of human chromosomal translocations.
  • (19) In order to maximize the utility of these tools a high degree of reliability is essential.
  • (20) Extraction tools included flexible, telescoping sheaths advanced over the lead to dilate scar tissue and apply countertraction, deflection catheters, and wire basket snares.