Many controlled human studies examining the effects of SO2 are available and indicate that the respiratory system is the principal target after acute exposure. Data show that asthmatics are particularly sensitive to the effects of SO2 and that effects are enhanced (in both healthy individuals and asthmatics) by exercise. Since it would not be feasible to include all available human SO2 data, the studies summarized below are considered sufficient to be quantitatively representative of data describing effects from acute exposure to SO2. Selected data from controlled exposures to SO2 in non-asthmatic individuals are presented in Table 9-3 and data from asthmatic individuals are presented in Table 9-4.
Target 3 Billion Book Pdf 43l
Fourteen asthmatics (12 male, 2 female, ages 19-50 years) were exposed to 0, 0.5, or 1.0 ppm SO2 for 10 min during light, medium, or heavy exercise (average ventilation 30, 36, and 43 L/min, respectively) (Gong et al. 1995). The ventilation rates were targeted to bracket a typical adult switching point from nasal to oronasal breathing. Exposures were con-ducted in a double-walled insulated cubical plexiglass chamber (2.2 m3). Air was supplied at a rate of 15 air changes/hour with no recirculation. SO2 was metered into the air supply from a cylinder containing 5% SO2 in nitrogen; concentration was continuously monitored with a pulsed fluorescent analyzer. At 0.5 ppm SO2 during light exercise, mild to moderate (subjective ratings on a 1 to 10 scale) respiratory effects were reported by subjects, while at 1.0 ppm and heavy exercise, effects were rated as moderate to severe. Effects included shortness of breath, wheezing, and chest tightness. Both FEV1 and SRaw showed significant (p>0.05) exposure-related effects; however, the exact magnitude is difficult to ascertain from the format of the reported data.
Although no specific concentrations were reported, case reports suggest that exposure to apparently high concentrations of SO2 may cause death via asphyxia secondary to pulmonary edema and irreversible airway obstruction. Epidemiological studies from occupational exposures and ambient air pollution also indicate that the respiratory system is the primary target for SO2 toxicity. With regard to air pollution, the elderly and chronically ill appear to be more sensitive than healthy young adults; however, attributing the observed toxicity to SO2 is difficult due to the presence of confounding factors such as smoke, particulates, and other air pollutants. Controlled experimental studies show that mild irritation, bronchoconstriction, and lung function changes are observed after exposure to low concentrations of SO2. Asthmatics are more sensitive than healthy people to the effects of SO2 and healthy elderly subjects may be more sensitive than healthy young people, but less sensitive than asthmatics. Exercise exacerbates the respiratory effects of SO2 in both healthy and asthmatic subjects. Data also suggest that cold air, dry air, the presence of other parti-culates and oral, rather than nasal, breathing may enhance the toxic effects of SO2. The body of experimental data suggests that 0.25 ppm may be a threshold for bronchoconstriction in asthmatics, and that a significant proportion of asthmatics will experience bronchoconstriction requiring medication or cessation of activity at 0.4-0.5 ppm. Data also suggest that a maximum response is obtained during the first 10-min of exposure and that continued or repeated exposures do not enhance the bronchoconstrictive response. Occupational exposures suggest that SO2 may be clastogenic; however, because confounding factors, such as exposure to other chemicals, were not considered, no definitive conclusions can be made regarding genotoxicity. No information concerning reproductive/developmental toxicity or carcinogenicity was available.
Petruzzi et al. (1996) exposed adult male and female CD-1 mice to 0, 5, 12, or 30 ppm SO2 for 24 days, from 9 days before the formation of breeding pairs through pregnancy day 12-14. Exposures were near-continuous, covering approximately 80% of the total time and were conducted in stainless steel exposure chambers with a hatch glass in the front door. SO2 was delivered from aluminum bottles and differing concentrations were obtained by varying the flow and gas pressure from the bottles. SO2 concentrations were monitored with an ultra-violet SO2 analyzer. Actual concentrations were within 10% of target concentrations. Within 1 h of the start of exposure, increased rearing and social interactions were observed and were more evident in males than in females. Observations on days 3, 6, and 9 showed dose-dependent decreased grooming and increased digging. Food and water consumption decreased in treated animals and increased in controls after the formation of breeding pairs. No effects were noted for reproductive performance or neurobehavioral development of the offspring. In another report from the same laboratory, the male CD-1 mice prenatally exposed to 0, 5, 12, or 30 ppm SO2 from the Petruzzi et al. (1996) study were examined for changes in behavior as adults (Fiore et al. 1998). At adulthood, following a 4 week isolation period, they underwent a 20 min aggressive encounter with a CD-1 male opponent. Dose-related increases were noted for body sniffing and nonsocial activities, whereas freezing, tail rattling, and defensive behaviors were decreased.
The Operating Thetan texts are kept secret from followers, and are only revealed after followers have typically given hundreds of thousands of dollars to the organization in order to complete what Scientology refers to as The Bridge to Total Freedom.[12] The Scientology organization has gone to considerable lengths to try to maintain the secrecy of the texts but they are freely available on the internet.[13] These texts say that lives preceding a thetan's arrival on Earth were lived in extraterrestrial cultures. Scientology doctrine states that any Scientologist undergoing "auditing" will eventually come across and recount what is called the "Incident".[14] The secret texts refer to an alien being called Xenu. They say Xenu was a ruler of a confederation of planets 70 million years ago who brought billions of aliens to Earth and then killed them with thermonuclear weapons. Despite being kept secret from most followers, this forms the central mythological framework of Scientology's ostensible soteriology.[15] These aspects have become the subject of popular ridicule.
Later that year, Hubbard published his ideas as the book, Dianetics: The Modern Science of Mental Health.[117] Published by Hermitage House, the first edition contained an introduction from medical doctor Joseph A. Winter and an appendix by the philosopher Will Durant.[118] Dianetics subsequently spent 28 weeks as a New York Times bestseller.[a][119][120] Urban suggested that Dianetics was "arguably the first major book of do-it-yourself psychotherapy".[121]
As Dianetics developed, Hubbard began claiming that auditing was revealing evidence that people could recall past lives and thus provided evidence of an inner soul or spirit.[144][145] This shift into metaphysical territory was reflected in Hubbard's second major book on Dianetics, Science of Survival (1951).[146] Some Dianetics practitioners distanced themselves from these claims, believing that they veered into supernaturalism and away from Dianetics' purported scientific credentials.[147] Several of Hubbard's followers, including Campbell and Winter, distanced themselves from Hubbard, citing the latter's dogmatism and authoritarianism.[148]
In 2008, the online activist collective Anonymous launched Project Chanology with the stated aim of destroying the Church; this entailed denial of service attacks against Church websites and demonstrations outside its premises.[208] In 2009, the St Petersburg Times began a new series of exposes surrounding alleged abuse of Church members, especially at their re-education camp at Gilman Hot Springs in California.[209] As well as prompting episodes of BBC's Panorama and CNN's AC360 investigating the allegations,[210] these articles launched a new series of negative press articles and books presenting themselves as exposes of the Church.[211]
Hubbard lies at the core of Scientology.[220] His writings remain the source of Scientology's doctrines and practices,[221] with the sociologist of religion David G. Bromley describing the religion as Hubbard's "personal synthesis of philosophy, physics, and psychology."[222] Hubbard claimed that he developed his ideas through research and experimentation, rather than through revelation from a supernatural source.[223] He published hundreds of articles and books over the course of his life,[224] writings that Scientologists regard as scripture.[225] The Church encourages people to read his work chronologically, in the order in which it was written.[226] It claims that Hubbard's work is perfect and no elaboration or alteration is permitted.[227] Hubbard described Scientology as an "applied religious philosophy" because, according to him, it consists of a metaphysical doctrine, a theory of psychology, and teachings in morality.[228]
Scientology teaches the existence of reincarnation;[265] Hubbard taught that each individual has experienced "past lives", although generally avoided using the term "reincarnation" itself.[266] The movement claims that once a body dies, the thetan enters another body which is preparing to be born.[242] It rejects the idea that the thetan will be born into a non-human animal on Earth.[267] In Have You Lived Before This Life?, Hubbard recounted accounts of past lives stretching back 55 billion years, often on other planets.[107]
Scientologists often refer to Hubbard affectionately as "Ron,"[382] and many refer to him as their "friend."[383] The Church operates a calendar in which 1950, the year in which Hubbard's book Dianetics was published, is considered year zero, the beginning of an era. Years after that date are referred to as "AD" for "After Dianetics."[384] They have also buried copies of his writings preserved on stainless steel disks in a secure underground vault in the hope of preserving them from major catastrophe. [380] The Church's view of Hubbard is presented in their authorised biography of him, their RON series of magazines, and their L. Ron Hubbard Life Exhibition in Los Angeles.[381] The Church's accounts of Hubbard's life have been characterised as being largely hagiographical,[385] seeking to present him as "a person of exceptional character, morals and intelligence".[386] Critics of Hubbard and his Church claim that many of the details of his life as he presented it were false.[387] 2ff7e9595c
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