The genus Echinococcus includes six parasite species of cyclophyllid tapeworms to date, of the family Taeniidae. Infection with Echinococcus results in hydatid disease known as echinococcosis. Echinococcus is triploblastic – it has three layers – outermost ectoderm, middle mesoderm, inner endoderm. An anus is absent, it has no digestive system, its body is covered by tegument and the worm is divided into a scolex, a short neck, three to six proglottids. Its body shape is ribbon-like. In humans, this causes; the three types of echinococcosis are cystic echinococcosis caused by E. granulosus, alveolar echinococcosis caused by E. multilocularis, polycystic echinococcosis caused by E. vogeli or E. oligarthrus. A worm's incubation period is long and can be up to 50 years. Cystic echinococcosis is found in South and Central America, the Middle East, Italy, Greece and the western United States. Echinococcosis is a zoonosis; the definitive hosts are carnivorous predators – dogs, wolves and lions. The adult tapeworm delivers eggs to be excreted with the stool.
The intermediate hosts are infected by ingesting eggs. Sheep, cattle, pigs, wild herbivores, rodents are the usual intermediate hosts, but humans can be infected. Humans are dead-end hosts, since their corpses are nowadays eaten by carnivorous predators; the egg hatches in the digestive system of the intermediate host. It penetrates the intestinal wall and is carried by bloodstream to liver, brain, or another organ, it turns into a bladder-like structure called hydatid cyst. From the inner lining of its wall, protoscoleces protrude into the fluid filling the cyst. After the death of the normal intermediate host, its body can be eaten by carnivores suitable as definitive hosts. In their small intestines, protoscoleces turn inside out and give rise to adult tapeworms, completing the lifecycle. In humans, the cysts grow for years, they are found in the liver and are asymptomatic until their growing size produces symptoms or are accidentally discovered. Disruption of the cysts can be life-threatening due to anaphylactic shock.
Cysts are detected with X-ray computed tomography, or other imaging techniques. Antiechinococcus antibodies can be detected with serodiagnostic tests – indirect fluorescent antibody, complement fixation, ELISA, Western blot, other methods. A phylogenetic tree has been created for several species in this genus – Echinococcus oligarthrus, Echinococcus vogeli, Echinococcus multilocularis, Echinococcus shiquicus, Echinococcus equinus, Echinococcus ortleppi, Echinococcus granulosus; the first diverging species are the neotropical endemic species E. oligarthrus and E. vogeli. E. ortleppi and E. canadensis are sister species, as are E. shiquicus. E. canadensis is related to E. granulosus. The origin of these parasites based on host-parasite co-evolution comparisons was North America or Asia, depending on whether the ancestral definitive hosts were canids or felids. Echinococcus oligarthrus and Echinococcus vogeli are basal in this genus; the genus is a sister to the genus Taenia. The genus Echinococcus evolved in North America in canids and began to diversify 5.8 million years ago.
There is no vaccine against Echinococcus multilocularis. However it is possible to protect humans from the fox tapeworm by deworming the main hosts
Tapeworm is a defunct side project of Nine Inch Nails which existed in various forms from 1995 to 2004. Tapeworm never released any recordings, but was referenced in interviews; the band started as a side-project between Nine Inch Nails frontman Trent Reznor and live-band members Danny Lohner and Charlie Clouser. Through the years the group expanded and evolved numerous times to include artists such as Maynard James Keenan, Atticus Ross, Alan Moulder turning the project into a supergroup. After many years of rumors and expected release dates, Reznor announced the end of the project in 2004. Tapeworm's genesis occurred during Nine Inch Nails recording sessions following The Downward Spiral tours circa 1996. While working on Nine Inch Nails material, Danny Lohner and Charlie Clouser, both Nine Inch Nails live band members, would come up with ideas that Reznor felt did not fit in with his vision for the band. Tapeworm developed as an outlet for this material—a democratic group in which Lohner and Clouser could act as equals with Reznor, as opposed to Nine Inch Nails, in which Reznor maintained sole artistic control.
As time went on, Tapeworm evolved into a supergroup, with guest musicians such as Maynard James Keenan, Page Hamilton, Phil Anselmo recording material ostensibly to be used by the group. In 1999 Lohner reported that three tracks had been completed, described the various materials featuring Anselmo as "heavy NIN-meets-Pantera" and "mellow Pink Floyd The Wall-type songs", the material featuring Keenan as "psychedelic, groove-oriented verses and anthemic choruses."Tommy Victor recorded material with the band as well, told Rolling Stone that the continued delays on Tapeworm contributed to his decision to take a hiatus from music, as well as accusing Reznor of giving his Tapeworm guitar contribution to Marilyn Manson. In a statement issued to MTV News, Reznor reflected on his collaborations with Keenan: It has been an interesting experiment for Maynard and I to peek around in each other's heads, shining flashlights in some shadowy corners... We've realized we're each in somewhat similar places in our respective lives and outlook, so it's been great to collaborate on that level.
By 2001, long-time Nine Inch Nails collaborator Alan Moulder had tracked "more than an album's worth" of demos. Moulder further described the rough tracks as "very unlike The Fragile" and were a deviation from most Nine Inch Nails material. By 2002, Clouser was no longer associated with Tapeworm; the group, which now consisted of Reznor, Lohner and Atticus Ross, booked time in a recording studio in hopes of producing an album. An official website, tapeworm.net, was created to showcase pictures from various recording sessions, including images of Josh Freese behind a drum kit. In September 2003, Lohner told Kerrang! magazine that the album was "ready to mix" but had been held up by legal issues stemming from conflicts between Reznor and Keenan's record labels. The Tapeworm material was reported numerous times as completion neared, most notably by MTV News and Kerrang!, was slated to be released on Reznor's Nothing Records label. Initial recording sessions for the band were staged in the Nothing Studios in New Orleans, though were reported as being moved to Southern Tracks Studios in Atlanta, Georgia.
In 2004, Reznor announced that Tapeworm was "dead for the foreseeable future", citing label issues, Keenan's A Perfect Circle obligations, Reznor's own waning enthusiasm for the project. Reznor summarized the project's demise by saying "the bottom line is this: if the music had been great, all of this could have been worked out." During an interview with digg founder Kevin Rose in 2009, Reznor further commented that he thought the material was not as good as could have been given his and Keenan's respective backgrounds and it was unlikely that the material would surface, but went on to say that he would like for the two of them to work together again at some point in the future. Musicians who have been cited as recording material for Tapeworm, in alphabetical order: Only two songs "Vacant" and "Potions", have been identified as Tapeworm songs. Neither have been released, though cover versions by Maynard James Keenan's other projects have surfaced; the first, "Vacant" was conceived during the Tapeworm sessions.
The song was first performed live by A Perfect Circle throughout their 2001 tour. MTV reported that Reznor was not happy that Keenan performed the song: "I have to admit I find it mildly irritating for "Vacant" to debut in this fashion before feeling it has been properly realized," Shortly after the dissolution of the Tapeworm project, Keenan released a reworked version on A Perfect Circle's 2004 cover album Emotive under the title "Passive". Another side-project of Maynard James Keenan, released an album titled "C" Is for with a song, "Potions," which had writing credits given to Trent Reznor. In response to rumors that Keenan released a Tapeworm song without any changes made, a blog was posted on the home page of the main Puscifer website on November 18, 2009 saying that: Ok. Let's use an APC album as an example. EMOTIVe. APC did a song called "Imagine." If you view the credits for the song you'll find various bits of info. Speaking the writers name appears in parenthesis next to the track; the performer info may not be listed in the album credits.
If you see performer info it may be broken down to instruments. For example... "Billy Howerdel - Guitars and Back-up Vocals. Josh Freese - Drums and percu
In evolutionary biology, parasitism is a relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it some harm, is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include protozoans such as the agents of malaria, sleeping sickness, amoebic dysentery. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism, trophically transmitted parasitism, vector-transmitted parasitism and micropredation. Like predation, parasitism is a type of consumer-resource interaction, but unlike predators, with the exception of parasitoids, are much smaller than their hosts, do not kill them, live in or on their hosts for an extended period. Parasites of animals are specialised, reproduce at a faster rate than their hosts. Classic examples include interactions between vertebrate hosts and tapeworms, the malaria-causing Plasmodium species, fleas.
Parasites reduce host fitness by general or specialised pathology, from parasitic castration to modification of host behaviour. Parasites increase their own fitness by exploiting hosts for resources necessary for their survival, in particular by feeding on them and by using intermediate hosts to assist in their transmission from one definitive host to another. Although parasitism is unambiguous, it is part of a spectrum of interactions between species, grading via parasitoidism into predation, through evolution into mutualism, in some fungi, shading into being saprophytic. People have known about parasites such as roundworms and tapeworms since ancient Egypt and Rome. In Early Modern times, Antonie van Leeuwenhoek observed Giardia lamblia in his microscope in 1681, while Francesco Redi described internal and external parasites including sheep liver fluke and ticks. Modern parasitology developed in the 19th century. In human culture, parasitism has negative connotations; these were exploited to satirical effect in Jonathan Swift's 1733 poem "On Poetry: A Rhapsody", comparing poets to hyperparasitical "vermin".
In fiction, Bram Stoker's 1897 Gothic horror novel Dracula and its many adaptations featured a blood-drinking parasite. Ridley Scott's 1979 film Alien was one of many works of science fiction to feature a terrifying parasitic alien species. First used in English in 1539, the word parasite comes from the Medieval French parasite, from the Latin parasitus, the latinisation of the Greek παράσιτος, "one who eats at the table of another" and that from παρά, "beside, by" + σῖτος, "wheat", hence "food"; the related term parasitism appears in English from 1611. Parasitism is a kind of symbiosis, a close and persistent long-term biological interaction between a parasite and its host. Unlike commensalism and mutualism, the parasitic relationship harms the host, either feeding on it or, as in the case of intestinal parasites, consuming some of its food; because parasites interact with other species, they can act as vectors of pathogens, causing disease. Predation is by definition not a symbiosis, as the interaction is brief, but the entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one".
Within that scope are many possible strategies. Taxonomists classify parasites in a variety of overlapping schemes, based on their interactions with their hosts and on their life-cycles, which are sometimes complex. An obligate parasite depends on the host to complete its life cycle, while a facultative parasite does not. Parasite life-cycles involving only one host are called "direct". An endoparasite lives inside the host's body. Mesoparasites - like some copepods, for example - enter an opening in the host's body and remain embedded there; some parasites can be generalists, feeding on a wide range of hosts, but many parasites, the majority of protozoans and helminths that parasitise animals, are specialists and host-specific. An early basic, functional division of parasites distinguished macroparasites; these each had a mathematical model assigned in order to analyse the population movements of the host–parasite groupings. The microorganisms and viruses that can reproduce and complete their life cycle within the host are known as microparasites.
Macroparasites are the multicellular organisms that reproduce and complete their life cycle outside of the host or on the host's body. Much of the thinking on types of parasitism has focussed on terrestrial animal parasites of animals, such as helminths; those in other environments and with other hosts have analogous strategies. For example, the snubnosed eel is a facultative endoparasite that opportunistically burrows into and eats sick and dying fish. Plant-eating insects such as scale insects and caterpillars resemble ectoparasites, attacking much larger plants; as female scale-insects cannot move, they are obligate parasites, permanently attached to their hosts. There are six major parasitic strategies, namely parasitic castration, directly transmitted parasitism, trophically transmitted parasitism, vector-transmitted parasitism, parasitoid
In biology, a cirrus SIRR-əs, plural cirri, SIRR-eye, is a long, thin structure in an animal similar to a tentacle but lacking the tentacle's strength, flexibility and sensitivity. In the sheep liver fluke, for example, the cirrus is the worm's muscular penis and when not in use is retained within a cirrus sac or pouch near the animal's head; the same structure exists in the various Taenia species of tapeworm. In the clam worms, the cirrus is the tentacular process or growth on each of the feet, either the dorsal cirrus or the ventral cirrus, has nothing to do with reproduction. Among the ribbonworms, the caudal cirrus is a small thread-like growth at the posterior end of the worm. Among the bristleworms, a cirrus is a tentacular growth near the head or notopodium containing sense organs and may be either dorsal, ventral, or lamellar. Among feather stars or barnacles, a cirrus is feeding appendage. In sea lilies, the cirri are the thin strands. Among the tube blennies, a cirrus is a long growth extending from above the eye or extending below the neck-region.
In a nautilus, each of the animal's tentacles is composed of a thin flexible cirrus and the corresponding hardened and protective cirrus sheath into which the cirri may be withdrawn
Taenia saginata known as the beef tapeworm, is a zoonotic tapeworm belonging to the order Cyclophyllidea and genus Taenia. It is an intestinal parasite in humans causing cysticercosis in cattle. Cattle are the intermediate hosts, where larval development occurs, while humans are definitive hosts harbouring the adult worms, it is found globally and most prevalently where cattle are raised and beef is consumed. It is common in Africa, Southeast Asia, South Asia, Latin America. Humans are infected as a result of eating raw or undercooked beef which contains the infective larvae, called cysticerci; as hermaphrodites, each body segment called proglottid has complete sets of both male and female reproductive systems. Thus, reproduction is by self-fertilisation. From humans, embryonated eggs, called oncospheres, are released with faeces and are transmitted to cattle through contaminated fodder. Oncospheres develop inside muscle and lungs of cattle into infective cysticerci. T. Saginata has a strong resemblance to the other human tapeworms, such as Taenia asiatica and Taenia solium, in structure and biology, except for few details.
It is larger and longer, with more proglottids, more testes, higher branching of the uteri. It lacks an armed scolex unlike other Taenia. Like the other tapeworms, it causes taeniasis inside the human intestine, but does not cause cysticercosis, its infection is harmless and clinically asymptomatic. T. saginata is the largest of species in the genus Taenia. An adult worm is 4 to 10 m in length, but can become large. Typical of cestodes, its body is flattened dorsoventrally and segmented, it is covered by a tegument. The body is white in colour and consists of three portions: scolex and strobila; the scolex has four suckers. Lack of hooks and a rostellum is an identifying feature from other Taenia species; the rest of the body proper, the strobila, is a chain of numerous body segments called proglottids. The neck is the shortest part of the body, consists of immature proglottids; the midstrobila is made of mature proglottids that lead to the gravid proglottids, which are at the posterior end. An individual can have as many as 1000 to 2000 proglottids.
T. saginata does not have a digestive system, anus, or digestive tract. It derives nutrients from the host through its tegument, as the tegument is covered with absorptive hair-like microtriches, it is an acoelomate, having no body cavity. The inside of each mature proglottid is filled with muscular layers and complete male and female reproductive systems, including the tubular unbranched uterus, genital pore and vitelline gland. In the gravid proglottid, the uterus contains up to 15 side branches filled with eggs. Cattle acquire the oncospheres, when they eat contaminated food. Oncospheres enter the duodenum, the anterior portion of the small intestine, hatch there under the influence of gastric juices; the embryonic membranes are removed, liberating free hexacanth larvae. With their hooks, they attach to the intestinal wall and penetrate the intestinal mucosa into the blood vessels; the larvae can move to all parts of the body by the general circulatory system, settle in skeletal muscles within 70 days.
Inside the tissue, they cast off their hooks and instead develop a protective cuticular shell, called the cyst. Thus, they become fluid-filled cysticerci. Cysterci can form in lungs and liver; the inner membrane of the cysticercus soon develops numerous protoscolices that are invertedly attached to the inner surface. The cysticercus of T. saginata is named cysticercus bovis to differentiate from that of T. solium, cysticercus cellulosae. Humans contract infective cysticerci by eating undercooked meat. Once reaching the jejunum, the inverted scolex becomes evaginated to the exterior under stimuli from the digestive enzymes of the host. Using the scolex, it attaches to the intestinal wall; the larva mature into adults about 5 to 12 weeks later. Adult worms can live about 25 years in the host. Only a single worm is present at time, but multiple worms are reported. In each mature proglottid, self-fertilisation produces zygotes, which divide and differentiate into embryonated eggs called oncospheres. With thousands of oncospheres, the oldest gravid proglottids detach.
Unlike in other Taenia, gravid proglottids are shed individually. In some cases, the proglottid ruptures inside the intestine, the eggs are released; the free proglottids and liberated eggs are removed by peristalsis into the environment. On the ground, the proglottids shed eggs as they move; these oncospheres in an external environment can remain viable for several days to weeks in sewage and pastures. The disease is common in Africa, some parts of Eastern Europe, the Philippines, Latin America; this parasite is found anywhere where beef is eaten in countries such as the United States, with strict federal sanitation policies. In the US, the incidence of infection is low; the total global infection is estimated to be between 60 million. It is most prevalent in the Middle East. T. saginata infection is asymptomatic, but heavy infection results in weight loss, abdominal pain, headaches, constipation, chronic indigestion, loss of appetite. Intestinal obstruction in humans can be alleviated by surgery.
The tapeworm can expel antigens that can cause an allergic reaction in
A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. It uses a computer network to spread itself, relying on security failures on the target computer to access it. Worms always cause at least some harm to the network if only by consuming bandwidth, whereas viruses always corrupt or modify files on a targeted computer. Many worms are designed only to spread, do not attempt to change the systems they pass through. However, as the Morris worm and Mydoom showed these "payload-free" worms can cause major disruption by increasing network traffic and other unintended effects; the actual term "worm" was first used in The Shockwave Rider. In that novel, Nichlas Haflinger designs and sets off a data-gathering worm in an act of revenge against the powerful men who run a national electronic information web that induces mass conformity. "You have the biggest-ever worm loose in the net, it automatically sabotages any attempt to monitor it...
There's never been a worm with that tough a head or that long a tail!"On November 2, 1988, Robert Tappan Morris, a Cornell University computer science graduate student, unleashed what became known as the Morris worm, disrupting a large number of computers on the Internet, guessed at the time to be one tenth of all those connected. During the Morris appeal process, the U. S. Court of Appeals estimated the cost of removing the virus from each installation at between $200 and $53,000. Morris himself became the first person tried and convicted under the 1986 Computer Fraud and Abuse Act. Any code designed to do more than spread the worm is referred to as the "payload". Typical malicious payloads might delete files on a host system, encrypt files in a ransomware attack, or exfiltrate data such as confidential documents or passwords; the most common payload for worms is to install a backdoor. This allows the computer to be remotely controlled by the worm author as a "zombie". Networks of such machines are referred to as botnets and are commonly used for a range of malicious purposes, including sending spam or performing DoS attacks.
Worms spread by exploiting vulnerabilities in operating systems. Vendors with security problems supply regular security updates, if these are installed to a machine the majority of worms are unable to spread to it. If a vulnerability is disclosed before the security patch released by the vendor, a zero-day attack is possible. Users need to be wary of opening unexpected email, should not run attached files or programs, or visit web sites that are linked to such emails. However, as with the ILOVEYOU worm, with the increased growth and efficiency of phishing attacks, it remains possible to trick the end-user into running malicious code. Anti-virus and anti-spyware software are helpful, but must be kept up-to-date with new pattern files at least every few days; the use of a firewall is recommended. In the April–June 2008 issue of IEEE Transactions on Dependable and Secure Computing, computer scientists described a new and effective way to combat internet worms; the researchers discovered how to contain worms that scanned the Internet randomly, looking for vulnerable hosts to infect.
They found that the key was to use software to monitor the number of scans that machines on a network send out. When a machine started to send out too many scans, it was a sign that it has been infected, which allowed administrators to take it off line and check it for malware. In addition, machine learning techniques can be used to detect new worms, by analyzing the behavior of the suspected computer. Users can minimize the threat posed by worms by keeping their computers' operating system and other software up to date, avoiding opening unrecognized or unexpected emails and running firewall and antivirus software. Mitigation techniques include: ACLs in routers and switches Packet-filters TCP Wrapper/ACL enabled network service daemons Nullroute Beginning with the first research into worms at Xerox PARC, there have been attempts to create useful worms; those worms allowed testing by John Shoch and Jon Hupp of the Ethernet principles on their network of Xerox Alto computers. The Nachi family of worms tried to download and install patches from Microsoft's website to fix vulnerabilities in the host system—by exploiting those same vulnerabilities.
In practice, although this may have made these systems more secure, it generated considerable network traffic, rebooted the machine in the course of patching it, did its work without the consent of the computer's owner or user. Regardless of their payload or their writers' intentions, most security experts regard all worms as malware. Several worms, like XSS worms, have been written to research. For example, the effects of changes in social activity or user behavior. One study proposed what seems to be the first computer worm that operates on the second layer of the OSI model, it utilizes topology information such as Content-addressable memory tables and Spanning Tree information stored in switches to propagate and probe for vulnerable nodes until the enterprise network is covered. Botnet Code Shikara Computer and network surveillance Computer virus Email spam Father Christmas Self-replicating machine Timeline of computer viruses and worms Trojan horse XSS worm Zombie Malware Guide – Guide for understanding and preventing worm infections on Vernalex.com.
"The'Worm' Programs – Early Experience with a Distributed Computation", John Shoch and Jon Hupp, Communications of the ACM, Volum
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, sponges, to the substrate. Holdfasts vary in form depending on both the species and the substrate type; the holdfasts of organisms that live in muddy substrates have complex tangles of root-like growths. These projections are called haptera and similar structures of the same name are found on lichens; the holdfasts of organisms that live in sandy substrates are bulb-like and flexible, such as those of sea pens, thus permitting the organism to pull the entire body into the substrate when the holdfast is contracted. The holdfasts of organisms that live on smooth surfaces have flattened bases which adhere to the surface; the organism derives no nutrition from this intimate contact with the substrate, as the process of liberating nutrients from the substrate requires enzymatically eroding the substrate away, thereby increasing the risk of organism falling off the substrate.
The claw-like holdfasts of kelps and other algae differ from the roots of land plants, in that they have no absorbent function, instead serving only as an anchor