Higgs data does not rule out a sequential fourth generation with an extended scalar sector

We consider the model of modified gravity with dynamical torsion. This model was previously found to have promising stability properties about various backgrounds. Here, we study the stability of linear perturbations about the self-accelerating solution. We apply the (3[Formula: see text]+[Formula: see text]1)-decomposition and consider the scalar sector of perturbations. We find that the number of degrees of freedom is equal to 2, which is the same as in Minkowski background. However, there is at least one instability in the scalar sector, if the value of background torsion is large enough. This does not rule out the possibility of stable self-acceleration with torsion of the order of the effective cosmological constant.

Download Full-text

A rapid method for the direct identification of paramyxovirus in canine CSF by ultracentrifugation and negative staining as a rule out for distemper

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160522 ◽

1990 ◽

Vol 48 (3) ◽

pp. 594-595

Author(s):

W.L. Steffens ◽

M.B. Ard ◽

C.E. Greene ◽

A. Jaggy

Keyword(s):

Subacute Sclerosing Panencephalitis ◽

Clinical Signs ◽

Viral Disease ◽

Etiologic Agent ◽

Mucosal Inflammation ◽

Worldwide Distribution ◽

Negative Stain ◽

Viral Particles ◽

Systemic Manifestations ◽

Rule Out

Canine distemper is a multisystemic contagious viral disease having a worldwide distribution, a high mortality rate, and significant central neurologic system (CNS) complications. In its systemic manifestations, it is often presumptively diagnosed on the basis of clinical signs and history. Few definitive antemortem diagnostic tests exist, and most are limited to the detection of viral antigen by immunofluorescence techniques on tissues or cytologic specimens or high immunoglobulin levels in CSF (cerebrospinal fluid). Diagnosis of CNS distemper is often unreliable due to the relatively low cell count in CSF (<50 cells/μl) and the binding of blocking immunoglobulins in CSF to cell surfaces. A more reliable and definitive test might be possible utilizing direct morphologic detection of the etiologic agent. Distemper is the canine equivalent of human measles, in that both involve a closely related member of the Paramyxoviridae, both produce mucosal inflammation, and may produce CNS complications. In humans, diagnosis of measles-induced subacute sclerosing panencephalitis is through negative stain identification of whole or incomplete viral particles in patient CSF.

Download Full-text

Impairment Questions and Answers

Guides Newsletter ◽

10.1001/amaguidesnewsletters.1999.julaug02 ◽

1999 ◽

Vol 4 (4) ◽

pp. 4-4

Keyword(s):

Symptom Validity ◽

Validity Testing ◽

Symptom Validity Testing ◽

Negative Results ◽

Tunnel Vision ◽

Questions And Answers ◽

Blurry Vision ◽

Fatigue Evaluation ◽

Choice Testing ◽

Rule Out

Abstract Symptom validity testing, also known as forced-choice testing, is a way to assess the validity of sensory and memory deficits, including tactile anesthesias, paresthesias, blindness, color blindness, tunnel vision, blurry vision, and deafness—the common feature of which is a claimed inability to perceive or remember a sensory signal. Symptom validity testing comprises two elements: A specific ability is assessed by presenting a large number of items in a multiple-choice format, and then the examinee's performance is compared with the statistical likelihood of success based on chance alone. Scoring below a norm can be explained in many different ways (eg, fatigue, evaluation anxiety, limited intelligence, and so on), but scoring below the probabilities of chance alone most likely indicates deliberate deception. The positive predictive value of the symptom validity technique likely is quite high because there is no alternative explanation to deliberate distortion when performance is below the probability of chance. The sensitivity of this technique is not likely to be good because, as with a thermometer, positive findings indicate that a problem is present, but negative results do not rule out a problem. Although a compelling conclusion is that the examinee who scores below probabilities is deliberately motivated to perform poorly, malingering must be concluded from the total clinical context.

Download Full-text

Case Exercise: Toxic Exposure-Related Illness: Causation, Diagnosis, and Permanent Impairment

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2007.marapr02 ◽

2007 ◽

Vol 12 (2) ◽

pp. 4-8

Author(s):

Frederick Fung

Keyword(s):

Concentration Level ◽

Treatment Plan ◽

Toxic Exposure ◽

Dose Response Relationship ◽

Specialty Board ◽

History Of ◽

Subjective Complaints ◽

Based Medicine ◽

Illness Causation ◽

Rule Out

Abstract A diagnosis of toxic-related injury/illness requires a consideration of the illness related to the toxic exposure, including diagnosis, causation, and permanent impairment; these are best performed by a physician who is certified by a specialty board certified by the American Board of Preventive Medicine. The patient must have a history of symptoms consistent with the exposure and disease at issue. In order to diagnose the presence of a specific disease, the examiner must find subjective complaints that are consistent with the objective findings, and both the subjective complaints and objective findings must be consistent with the disease that is postulated. Exposure to a specific potentially causative agent at a defined concentration level must be documented and must be sufficient to induce a particular pathology in order to establish a diagnosis. Differential diagnoses must be entertained in order to rule out other potential causes, including psychological etiology. Furthermore, the identified exposure at the defined concentration level must be capable of causing the diagnosis being postulated before the examiner can conclude that there has been a cause-and-effect relationship between the exposure and the disease (dose-response relationship). The evaluator's opinion should make biological and epidemiological sense. The treatment plan and prognosis should be consistent with evidence-based medicine, and the rating of impairment must be based on objective findings in involved systems.

Download Full-text