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The Federal False Claims Act (FCA) creates civil liability for entities that falsely or fraudulently contract with the government to provide services or goods in exchange for federal funds. FCA cases often arise in healthcare contexts in which the government pays entities for providing products and services to eligible beneficiaries. With the growth of Medicare and Medicaid funding for healthcare services, there has been a corresponding increase of false claims and FCA cases, in the healthcare context. For instance, of the over 30 billion recovered by the government for FCA cases in the last fifteen years, recoveries from Health and Human Services constitutes over 20 billion.
An FCA case may involve a false representation that a service has been provided when in fact it has not. Such a case may also involve a false representation of compliance with underlying governmental requirements for payment. Recently, there has been growing confusion as to how to address cases in which the defendant is not the party actually submitting the allegedly false claim, but the party that caused the false claim to be filed.
Mycobacterium tuberculosis (Mtb) is a metabolically flexible pathogen that has the extraordinary ability to sense and adapt to the continuously changing host environment experienced during decades of persistent infection. Mtb is continually exposed to endogenous reactive oxygen species (ROS) as part of normal aerobic respiration, as well as exogenous ROS and reactive nitrogen species (RNS) generated by the host immune system in response to infection. The magnitude of tuberculosis (TB) disease is further amplified by exposure to xenobiotics from the environment such as cigarette smoke and air pollution, causing disruption of the intracellular prooxidant–antioxidant balance. Both oxidative and reductive stresses induce redox cascades that alter Mtb signal transduction, DNA and RNA synthesis, protein synthesis and antimycobacterial drug resistance. As reviewed in this article, Mtb has evolved specific mechanisms to protect itself against endogenously produced oxidants, as well as defend against host and environmental oxidants and reductants found specifically within the microenvironments of the lung. Maintaining an appropriate redox balance is critical to the clinical outcome because several antimycobacterial prodrugs are only effective upon bioreductive activation. Proper homeostasis of oxido-reductive systems is essential for Mtb survival, persistence and subsequent reactivation. The progress and remaining deficiencies in understanding Mtb redox homeostasis are also discussed.
Cognitive impairment precedes the diagnosis of Alzheimer's disease. It is unclear which psychometric measures predict dementia, and what cut-off points should be used. Replicable cognitive measures to provide information about differential diagnosis and prognosis would be clinically useful.
In a prospective cohort study we investigated which measures distinguish between individuals with amnestic mild cognitive impairment (aMCI) that converts to dementia and those whose impairment does not, and which combination of measures best predicts the fate of people with aMCI.
Forty-four participants with aMCI underwent extensive neuropsychological assessment at baseline and annually thereafter for an average of 4 years. Differences in baseline cognitive performance of participants who were converters and non-converters to clinically diagnosed dementia were analysed. Classification accuracy was estimated by sensitivity, specificity, positive and negative predictive values and using logistic regression.
Forty-one percent of participants had progressed to dementia by the end of study, with a mean annual conversion rate of 11%. Most (63%) showed persisting or progressive cognitive impairment, irrespective of diagnosis. The Addenbrooke's Cognitive Examination together with the discrimination index of the Hopkins Verbal Learning Test – Revised (but none of the demographic indices) differentiated the participants who were converters from the non-converters at baseline with 74% accuracy.
Targeted neuropsychological assessment, beyond simple cognitive screening, could be used in clinical practice to provide individuals with aMCI with prognostic information and aid selective early initiation of monitoring and treatment among those who progress towards a clinically diagnosable dementia.
The Isle of Ely is the northern half of the geographical County of Cambridge-shire and forms in itself a separate administrative county. It is the heart of the fen country, and its population is one which long retained a degree of isolation and independence tending to preserve in its members certain mental, and perhaps physical characters peculiar to themselves. It is interesting to recall that from this neighbourhood came Boadicea, Queen of the Iceni, and Hereward the Wake, who proved such stubborn enemies to the conquerors of their country.
Linear null points of a magnetic field may come together and coalesce at a secondorder null, or vice versa a second-order null may form and split, giving birth to a pair of linear nulls. Such local bifurcations lead to global changes of magnetic topology and in some cases release of magnetic energy. In two dimensions the null points are of X or O type and the flux function is a Hamiltonian; the magnetic field may undergo addle-centre, pitchfork or degenerate resonant bifurcations. In three dimensions the null points and their creation or annihilation by bifurcations are considerably more complex. The nulls possess a skeleton consisting of a spine curve and a fan surface and are of radial-type (proper or improper) or spiral-type; the type of null and the inclination of spine and fan depend on the magnitudes of the current components along and normal to the spine. In cylindrically symmetric fields a comprehensive treatment is given of the various types of saddle-node, Hopf and saddle-node—Hopfbifurcations. In fully three-dimensional situations examples are given of saddle-node and degenerate bifurcations, in which generically two nulls are created or destroyed and are joined by a separator field line, which is the intersection of the two fans. Furthermore, global bifurcations can create chaotic field lines that could perhaps trigger energy release in, for example, solar flares.
The dual task paradigm (Baddeley et al.1986; Della Sala et al.1995) has been proposed as a sensitive measure of Alzheimer's dementia, early in the disease process.
We investigated this claim by administering the modified dual task paradigm (utilising a pencil-and-paper version of a tracking task) to 33 patients with amnestic mild cognitive impairment (aMCI) and 10 with very early Alzheimer's disease, as well as 21 healthy elderly subjects and 17 controls with depressive symptoms. All groups were closely matched for age and pre-morbid intellectual ability.
There were no group differences in dual task performance, despite poor performance in episodic memory tests of the aMCI and early Alzheimer's disease groups. In contrast, the Alzheimer patients were specifically impaired in the trail-making test B, another commonly used test of divided attention.
The dual task paradigm lacks sensitivity for use in the early differential diagnosis of Alzheimer's disease.
There is current interest in exploring the different subtypes of mild
cognitive impairment (MCI), in terms of both their epidemiology and their
To examine the frequency of MCI subtypes presenting to a memory clinic
and to document detailed neuropsychological profiles of patients with the
Consecutive tertiary referrals (n = 187) were
psychiatrically evaluated; 45 patients met criteria for amnestic mild
cognitive impairment (aMCI). A subgroup of 33 patients with aMCI as well
as 21 healthy controls took part in a thorough neuropsychological
Of the patients who were examined in greater neuropsychological detail,
ten had pure aMCI (none with visual memory impairment only). Fifteen met
criteria for non-amnestic MCI. Fifteen had normal neuropsychological
profiles. Using more than one test increased sensitivity to detect
episodic memory impairment.
Amnestic MCI is an important diagnosis in secondary and tertiary memory
clinics. There is scope to improve the efficacy and sensitivity of the
clinical assessment of this impairment.
The compatibility of both bulk and porous silicon at the subcutaneous site has been assessed for the first time, following ISO standard procedures. The in-vivo responses to implantation were monitored in the guinea pig and histopathological reactions evaluated at 1, 4, 12 and 26 weeks. Attention is focused here on the histological assessment protocols used, and the results demonstrating in-vivo evidence for good tissue compatibility, and porous Si bioactivity with regards calcification.
The response of a range of porous Si and poly Si films to storage in acellular simulated body fluids is summarised and its implications discussed. It is suggested that the combination of VLSI technology, micromachining and surface microstructuring achievable with silicon, could establish this prominent semiconductor as a very useful biomaterial by the next century. The ‘biocompatibility’ of a variety of silicon microstructures, and even bulk silicon has received surprisingly little study, but now warrants detailed in-vitro and in-vivo assessment.
The effect of the chemical thinning of the porous silicon structure on the speed and efficiency of electroluminescent devices, produced by the anodisation of a pn junction in bulk silicon is investigated. Thinning of the silicon wires results in an increase in the efficiency but at the expense of a reduction in operating speed. It is demonstrated that the operating speed is limited by the photoluminescence lifetime for small signal excitation. However, for large signals, the electroluminescence can be turned off more than 5 times faster than the photoluminescence lifetime, indicating that this need not necessarily limit device operating speed.
Galen in a celebrated passage remarks that there were three ‘choirs’, in early Greek medicine: the choirs of Cos, of Cnidus, and of Sicily. The word is vague and suggestive, and we do well to keep it so. If we look in the Hippocratic Corpus for schools of medical theory, with distinct sets of doctrine marked off clearly from the doctrines of rival schools, we shall be lucky indeed if we can find them, and, having found them, succeed in convincing others of their existence. But we shall find, now and again, an individual voice proclaiming itself from among its impersonal surroundings with clarity and vigour: some treatises in the collection have their author's personality stamped on them as distinctly as on a work of art.
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