This research will address the use of diatoms to aid in forensic cases/ investigations. Diatoms are unicellular photosynthetic organisms that are a major group of algae which, is the most common type of phytoplankton. They form colonies in the form of filaments/ ribbons and make up the base of food webs and chains. The first diatom Bacillaria paradoxa was discovered in 1783 by a Danish naturalist, Otto Friedrich Muller, who was involved in the study of microorganisms for most his life. Because of the abundance of diatoms in aquatic ecology, it remains the most popular tool for assessing environmental conditions and water quality.
Diatoms have a significant value in the forensic prospective, as it can be used in drowning cases to determine if the victim was actually drowned or not. The diatom test originated from the British Continent and the Forensic Pathology community has been, historically, polarized in its general acceptance of the diatom test as a definitive diagnostic test for drowning. (Sinhg R., et al, 2006). The test is based on the theory that normal people do not have any
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In 1861, (Guy WA., 1861) got an idea that water along with some mud and other debris fragments, channel to the various body organs when drowning takes place. While, a series of experiments were conducted on dogs and found that a quantity of water equal to a third or quarter of the subject's blood volume, enters the circulation when submersion takes place for about 20 minutes or more. (Brouardel P., 1880). But seventy years later (Swann HG., 1951) reported that only after 3 minutes of submersion the original blood volume could be diluted by same volume of water. First discovery of diatoms in lungs was made by (Hofmann E., 1878) but a successful attempt was made by (Revenstorf V., 1904) who correlated the presence of diatoms in the lungs in solving the drowning
The Daphnia magna species in this experiment were kept and preserved in jars of suitable water that acted as small ponds. Each Daphnia Magna was transported individually using a wide-mouthed pipette to a depression slide. The stability of the Daphnia Magna on the slide was attained by using a drop of pond water that acted as a boundary of movement for the Daphnia on the depression slide, small pieces of cotton wool were also used to act as an extra boundary to stop the Daphnia Magna from swimming in circles in the pond drop it was placed in; the stability factor was important in counting the heart beat rate more accurately. The depression slide was then placed under the stereomicroscope, over a cooling chamber that was used to slow down the
Cephalopods are known to be exceptionally intelligent by invertebrate standards and in some respects even rival “higher” vertebrates. These animals have many highly evolved sensory and processing organs that allow them to gain a greater understanding of their environment and their place within it. Due to their advanced structures, many of which are analogous to vertebrate structures, and abilities they have been widely studied. Their methods of learning have been of prime interest and many experiments have been conducted to determine the different ways in which octopuses can learn. From these experiments four main kinds of learning have been identified in octopuses: associative learning, special learning,
Poison arrow frogs are one of the most interesting animals of the Amazon rainforest. Poison Arrow Frogs are very colorful. The Poison arrow frogs skin holds all of the poison. Female Poison arrow frogs lay eggs in the water which then turn into tadpoles, when nursing the tadpoles stay on the females back. They’re colorful and vibrant body warn predators to not go near them. Most Poison arrow frogs are a bright colored. The Poison arrow frogs scientific name is Dendrobatidae. Poison arrow frogs are not poisonous in captivity. They gain their poison from bugs and arthropods that they eat. Poison arrow frogs gained their name from indian tribes putting the Poison arrow frogs poison on darts and arrows. Poison arrow frogs are small and about a centimetre tall and wide. The most poisonous part of a poison arrow frog is the Poison arrow frogs skin that can kill a 180 pound 6 ft man but usually it isn’t bad. All Poison frogs are poisonous but only 3 are deadly. The most poisonous and deadly Poison arrow frog is the famous Golden arrow frog. Its poison, Batrachotoxin can kill small animals and humans. As you can see Poison arrow frogs are unique and colorful frogs.
results of the forensic anthropology. For instance, if a crime is committed at a certain scene,
a)But this depends much upon the Degrees of the Distemper, and the original Frame and Make of the Body, even more than can be readily imaging, as I have often had undeniable Evidences to conclude. Pg introduction
Therefore, the criminal justice system relies on other nonscientific means that are not accepted or clear. Many of forensic methods have implemented in research when looking for evidence, but the methods that are not scientific and have little or anything to do with science. The result of false evidence by other means leads to false testimony by a forensic analyst. Another issue with forensic errors is that it is a challenge to find a defense expert (Giannelli, 2011). Defense experts are required to help the defense attorneys defend and breakdown all of the doubts in the prosecutors scientific findings in criminal cases. Scientific information is integral in a criminal prosecution, and a defense attorney needs to have an expert to assist he/she in discrediting the prosecution (Giannelli,
Forensic entomology is the learning of all types of insects and how they connect with criminal investigation. Forensic entomology can tell us how long since the offspring’s death which is known as postmortem interval (PMI) and whether the body has been relocated since putting one foot in the grave, and what injuries it may have suffered. At the start of decomposition, insects launch a new community by hatching eggs on the remains; the eggs will emerge into cankers (larvae) that will graze upon the human organs and tissues. A Forensic entomologists can figure out what specific bugs are presently in the body and gauge how long the body has been left unprotected by investigating how far along the cankers have come; although, what is found isn’t
Forensic toxicology is one of the oldest disciplines in forensic science history and dates back hundreds of years. However, the actual understanding and examination of forensic toxicology only dates back for about 200 years. Due to the development of technology, this discipline has been able to progress and flourish. The term forensic toxicology is defined as examination of all aspects of toxicity that may have legal implications (James & Nordby, 2009 p. 61).
Echinoderms are captivating organisms. They have a number of specialized structures and functions. They have unique water vascular systems, aboral surfaces, and feeding structures. This sets them apart from other animals because of their distinct characteristics.
There are an estimated 8,000 deaths per year in the United States from drowning. Near-drowning occurs anywhere from 2-20 times more frequently (for estimated 16,000-160,000 events per year)7. The definitions for drowning and near-drowning have for the longest time been very confusing to understand. Recent health officials have attempted to resolve some of this confusion by redefining drowning as “the process of experiencing respiratory insufficiency or difficulty following a submersion or immersion in a body of liquid.” Near-drowning has also been redefined as “survival from a drowning event which involved impaired consciousness or water inhalation for 24 hours or more”2. Both near drowning and near-drowning occur when someone experiences a submersion event. A submersion event is when someone, in this case a pediatric patient, experiences an unexpected submersion in water. When an unexpected submersion, regardless of water type (salt or fresh) occurs, the individual experiences breath hold, panic, and a struggle to resurface1. Humans, naturally, can only hold their breath for a short period of time. This prolonged breath hold results in hypoxia and eventually leads to involuntary gasping. As the individual attempts to gasp for air they sometimes aspirate7. This paper will attempt to look at the clinical presentation of a near-drowning patient who has suffered from a submersion event.
The overall goal of a forensic scientist is to determine the facts using all the available resources they were given. They give their expert opinion to the attorneys, judge, and jury, and depending on how well prepared they are, can sway the jury to either a guilty or innocent verdict (Thinkquest 2014). In general, a forensic expert must keep impeccable records of all that has b...
Forensic Entomology or the study of insects as they relate to medicolegal investigations is a relatively young yet fast growing science. Insects can be used in a variety of ways to prove or disprove facts of a case. It is up to the crime scene investigator to properly collect and preserve this evidence until an expert in the field of entomology can inspect the evidence and give their expert opinion. It is then up to the prosecution not to get the evidence thrown out due to showing excessive amounts of the same evidence or showing the jury inflammatory evidence that is hard for most people to stomach. Chances are as a common citizen, most people would find a majority of entomological evidence inflammatory due to the graphic nature it tends to
Geberth, Vernon J. (1983). Practical Homicide Investigation: Tactics, Procedures, and Forensic Technics. Elsevier Science Publishing Co., Inc.
Ely, S. F., & Hirsch, C. S. (2000). Asphyxial Deaths and Petechiae: A Review. Journal of Forensic Sciences, 45(6). doi:10.1520/jfs14878j
In news stories the world over there are cases of pets and occasionally humans that have fallen into icy lakes and been submerged for up to and over an hour. Often the human or pet will perish due to the cold temperature of the water but in some cases are pulled free and are resuscitated; surviving their ordeal and being effectively ‘restored’ from what is considered by normal standards certain death. The idea that conscious beings could survive such trauma is that the icy water lowers body temperature and places it into a state of suspended animation, slowing metabolism and brain function to levels where they require very little or no oxygen at all.